TRNG I HC VN LANG KHOA CNG NGH V QUN L MI TRNG GIO TRNH MN HC QUN L CHT THI RN TH GVC. TS. Trn Th M Diu TP. H Ch Minh, thng 9 nm 2011 MC LC Chng 1GII THIU CHUNG 11.1Mt s khi nim v nh ngha c bn21.2Cht thi rn th v cc vn mi trng31.3Tng quan v h thng qun l cht thi rn th Chng 2NGUN PHT SINH, KHI LNG, THNH PHN V TNH CHT CHT THI RN TH 2.1Cc ngun pht sinh cht thi rn th52.2Khi lng, tc pht sinh cht thi rn th52.2.1 La chn n v biu din khi lng, tc pht sinh cht thi rn52.2.2 Phng php kho st xc nh tc pht sinh cht thi rn72.2.3 Phng php d on khi lng v tc pht sinh cht thi rn202.3Thnh phn cht thi rn th v phng php xc nh232.3.1 Thnh phn cht thi rn th232.3.2 Phng php phn tch thnh phn cht thi rn242.4Tnh cht l hc, ha hc, sinh hc ca cht thi rn th252.4.1 Tnh cht l hc252.4.2 Tnh cht ha hc312.4.3 Tnh cht sinh hc36 Chng 3QUN L CHT THI RN TH TI NGUN 3.1Lu tr cht thi rn ti ngun383.1.1 nh hng ca vic lu tr n cc thnh phn cht thi383.1.2 Loi thng cha413.1.3 V tr t thng cha413.1.4 Sc khe cng ng v m quan423.2X l cht thi ti ngun42 Chng 4H THNG THU GOM CHT THI RN 4.1H Thng thu gom cht thi rn t cc ngun pht sinh c khi lng nh 444.1.1 Hnh thc thu gom444.1.2 Phng tin thu gom454.1.3 Phn tch tuyn thu gom, tnh ton trang thit b v nhn cng 464.2H thng thu gom cht thi rn t cc ngun pht sinh tp trung514.2.1 Hnh thc thu gom514.2.2 Phng tin thu gom524.2.3 Phn tch tuyn thu gom, tnh ton trang thit b v nhn cng524.3Vch Tuyn Thu Gom544.3.1 Nguyn tc vch tuyn544.3.2 Cc bc vch tuyn thu gom55 Chng 5TRUNG CHUYN V VN CHUYN 5.1S cn thit ca trm trungchuyn575.1Phn loi trm trung chuyn575.4Nhng yu cu thit k trm trung chuyn615.3Phng tin v phng php vn chuyn61 iiChng 6CNG NGH TI CH CHT THI 6.1Lon nhm656.2Giy v carton656.3Nha666.4Thy tinh686.5St v thp696.6Kim loi mu696.7Cao su696.8Pin gia dng696.9Rc thc phm Chng 7CNG NGH X L CHT THI RN TH 7.1Gii thiu chung717.2Phng php c hc717.3Cng ngh sinh hc x l k kh727.4Cng ngh sinh hc x l hiu kh807.5Cng ngh x l nhit94 Chng 8BI CHN LP HP V SINH 8.1Phng php chn lp cht thi rn978.2Phn loi, loi hnh v phng php chn lp1028.3Kim sot nc r rc1058.4Kim sot kh bi chn lp110 CHNG 1 GII THIU CHUNG 1.1 MT S KHI NIM V NH NGHA C BN Cht thi c hiu nh quy nh ti iu 2 ca Lut Bo V Mi Trng nm 2005: cht thi l vt cht dng rn, lng, kh, mi hoc cc dng khc thi ra t sinh hot, sn xut, kinh doanh, dch v hoc cc hot ng khc ca con ngi. Cht thi rn l tt c cc cht thi, pht sinh t cc hot ng ca con ngi v ng vt, thng dng rn v b b v khng s dng c hoc khng c mong mun na. Cht thi rn sinh hot l cht thi rn sinh ra t cc khu nh (bit th, h gia nh ringl,chungc,),khuthngmi(cahng,nhhng,ch,siuth,vnphng, khch sn, nh ngh, trm dch v, ca hng s xe,), c quan (trng hc, vin nghin cu,trungtm,bnhvin,nht,cctrungtmhnhchnhnhnc,)khudchv cng cng (qut ng, cng vin, gii tr, ta cy xanh,) v t cng tc no vt cng rnhthotnc.Chtthirnsinhhotbaogmcchtthinguyhisinhratcc ngun trn. Cht thi rn cng nghip l cht thi rn sinh ra trong qu trnh sn xut ca cc khu cng nghip, nh my, x nghip, cc c s sn xut va v nh. Cht thi rn cng nghip khng bao gm cht thi rn sinh hot ca cn b, cng nhn thi ra t cc khu cng nghip, nh my, x nghip, cc c s sn xut va v nh. Cht thi rn sinh hot v cng nghip cng cn c chia lm hai loi: (1) cht thi rn khng nguy hi v (2) cht thi rn nguy hi. Chtthirnnguyhilchtthirnhochpchtcaccchtthirn,dokhi lng, nng hoc do tnh cht vt l, ha hc hoc ly nhim c th: (a) gy hoc gp phn ng k lm tng s lng t vong hoc lm tng cc bnh nguy him (b) gy nguy hi n sc khe con ngi hoc mi trng khi khng c x l, lu tr, vn chuyn, b hoc qun l khng hp l. Cht thi nguy hi l cc loi cht thi (rn, bn, lng v cc loi kh ng bnh) tr cc cht thi phng x (v ly nhim), do hot tnh ha hc ca chng hoc tnh cht c hi, chy n, n mn, hoc cc tnh cht khc, gy nn mi nguy him hoc tng t n sc khe hoc mi trng, d n c hay tip xc vi cc cht thi khc. Nhvy,chtthinguyhilchtthicmttrongbntnhchtchy(ignitable),n mn (corrosive), phn ng (reactive), hoc c hi (toxic): Chng 1 - Gii thiu chung 2- Cht n mn: l cc cht lng c pH < 2 hoc >12,5 hoc c kh nng n mn thp ln hn 0,25 inches/nm (6,35 mm/nm). - Cht thi chy l cc cht lng c nhit chp chy nh hn 60oC hoc cht rn c kh nng gy chy nhit v p sut tiu chun. - Chtthi phn ngthnglccchtkhng nnh,phnng mnh litvinc hoc khng kh, hoc to thnh hn hp c kh nng n vi nc. - Cht thi c tnh c hi l cc cht thi c kh nng thot ra vi khi lng ng k trong nc nng ng k. Chtthirnthbaogmchtthirnsinhhottcckhudnc,tcccs cng nghip (khu cng nghip, khu ch xut, nh my, c s sn xut va v nh), t cc khuvcxydngvpph(xbn),khuvcnhmyxl(nhmyxlnc, nc thi sinh hot), l t cht thi rn th. 1.2 CHT THI RN TH V CC VN MI TRNG Cht thi rn sinh ra cha c thu gom v x l trit l ngun gy nhim c ba mi trng: t, nc v khng kh. Ti cc bi rc, nc r rc v kh bi rc l mi e da i vi ngun nc mt v nc ngm trong khu vc. Khi lng cht thi rn ca cc khu th ngy cng gia tng nhanh chng theo tc gia tng dn s v pht trin kinh t x hi. Lng cht thi rn nu khng c x l tt s dn n hng lot cc hu qu mi trng khng th lng trc c. Cc vn mi trng do cht thi rn gy ra thng l hu qu ca vic khng qun l hp l cht thi rn t ngun pht sinh n ni thi b cui cng. X thi ba bi cht thi rn xung knh rch lm nhim ngun nc mt nhiu khu vc. Chn lp cht thi rn khng hp v sinh gy nhim mi trng t, nc mt, nc ngm v khng kh hu ht cc khu vc c bi rc. l chaknccscmitrngkhcnhln,trtbichnlp,trnncrrcra mitrngxungquanh,mihithinhhngtrndinrng,phtsinhruimuiv cc loi cn trng, Chbngcchtchc,vnhnhvqunlmtcchhiuquchtthirntngun pht sinh n ni thi b cui cng mi c th gim c chi ph cng nh hn ch cc vn mi trng do rc gy ra. Khi tng khu trong h thng qun l cht thi rn th c t chc hp l v cc khu trong h thng ny c phi hp vn hnh mt cch nhpnhng,rcskhngcnlvnnnmitrngchoconngi.Nhngnidung trngtmtrongtnhton,thitkvvnhnhhthngqunlchtthirnths c trnh by xuyn sut gio trnh ny. 1.3 TNG QUAN V H THNG QUN L CHT THI RN TH Qun l cht thi rn l s kt hp kim sot ngun thi, tn tr, tho gom, trung chuyn v vn chuyn, x l v cht thi rn theo phng thc tt nht nhm m bo khng nh hng n sc khe cng ng, tha mn cc yu t v kinh t, k thut, bo tn ti nguyn thin nhin, gi gn cnh quan th v hn ch tt c cc vn mi trng lin quan. Qun l thng nht cht thi rn l vic la chn v p dng k thut, cng ngh v chng trnh qun l thch hp nhm hon thnh mc tiu c bit qun l cht thi rn. Gio trnh Qun l cht thi rn th 3Mt cch tng qut, s h thng k thut qun l cht thi rn th c trnh by tm tt trong Hnh 1.1. Ngun pht sinh. Ngun ch yu pht sinh cht thi rn th bao gm: (1) t cc khu dnc(chtthirnsinhhot),(2)cctrungtmthngmi,(3)cccngs,trng hc, cng trnh cng cng, (4) dch v th, sn bay, (5) cc hot ng cng nghip, (6) cc hot ng xy dng th, (7) cc trm x l nc thi v t cc ng cng thot nc ca thnh ph. Hnh1.1Stngquththngqunlchtthirnth(Tchobanoglousvcngs, 1993). Tn tr ti ngun. Cht thi rn pht sinh c lu tr trong cc loi thng cha khc nhau ty theo c im ngun pht sinh rc, khi lng rc cn lu tr, v tr t thng cha, chu k thu gom, phng tin thu gom, Mt cch tng qut, cc phng tin thu cha rc thng c thit k, la chn sao cho tha mn cc tiu chun sau: (1) chng s xm nhp ca sc vt, cn trng, (2) bn, chc, p v khng b h hng do thi tit, (3) d c ra khi cn thit. Thugom.Rcsaukhictptrungticcimquynhscthugomvvn chuynntrmtrungchuyn/trmxlhocbichnlp.Theokiuvnhnh,h thng thu gom c phn loi thnh: (1) h thng thu gom kiu thng cha di ng: loi c in v loi trao i thng cha v (2) h thng thu gom kiu thng cha c nh. Ty theocimcaphngtinthugomvnchuyn,lngrcvonngvn chuyn,saukhithugom,rcscchuynncctrmtrungchuyn/imhn chuyn sang xe c ti trng ln hn hoc c vn chuyn thng n bi chn lp. Rc cng c th c chuyn n khu ti ch, x l thu hi nhng thnh phn c gi tr, phn cn li sau mi c vn chuyn n bi chn lp. Trung chuyn v vn chuyn. Cc trm trung chuyn c s dng ti u ha nng sut lao ng ca i thu gom v i xe. Trm trung chuyn c s dng khi: (1) xy ra hin tng cht thi rn khng ng quy nh do khong cch vn chuyn qu xa, (2) vtrthibquxatuynngthugom(thnglnhn16km),(3)sdngxethu gom c dung tch nh (thng nh hn 15 m3), (4) khu vc phc v l khu dn c tha tht, (5) s dng thng cha tng i nh thu gom cht thi t khu thng mi. Hot Ngun pht sinh Tn tr ti ngun Thu gom Trung chuyn v vn chuyn Ti ch vx l Bi chn lp Chng 1 - Gii thiu chung 4ng ca mi trm trung chuyn bao gm: (1) tip nhn cc xe thu gom rc, (2) xc nh ti trng rc a v trm, (3) hng dn cc xe n im rc, (4) a xe thu gom ra khi trm, (5) x l rc (nu cn thit), (6) chuyn rc ln xe vn chuyn a n bi chnlp.ivimitrmtrungchuyncnxemxt:(1)slngxengthitrong trm, (2) khi lng v thnh phn rc c thu gom v trm, (3) bn knh hiu qu kinh t i vi mi loi xe thu gom, (4) thi gian xe thu gom i t v tr ly rc cui cng ca tuyn thu gom v trm trung chuyn. Tichvxl.Rtnhiuthnhphntrongrcthickhnngtichnh:giy, carton, ti nilon, nha, cao su, da, g, thy tinh, kim loi, Cc thnh phn cn li, ty theo phng tin k thut hin c s c x l bng cc phng php khc nhau nh: (1) sn xut phn compost, (2) sn xut kh sinh hc (biogas), (3) t thu hi nng lng hay (4) ra bi chn lp. Bichnlphpvsinh. Bichnlphpvsinhlphngphpxlvtiuhy cht thi rn n gin nht v chp nhn c v mt mi trng. Ngay c khi p dng cc bin php gim lng cht thi, ti s dng v ti ch, vic thi b phn cht thi cn li ra bi chn lp vn l mt khu quan trng trong h thng qun l thng nht cht thi rn. Mt bi chn lp cht thi rn th c gi l bi chn lp hp v sinh khi c thitkvvnhnhsaochogimnmcthpnhtcctcngnsckhecng ng v mi trng. Bi chn lp hp v sinh c thit k v vn hnh c lp lt y, cc lp che ph hng ngy v che ph trung gian, c h thng thu gom v x l nc r rc, h thng thu gom v x l kh thi, c che ph cui cng v duy tu, bo tr sau khi ng bi chn lp. Mi khu trong h thng qun l ny s c ln lt trnh by chi tit trong cc chng tip theo ca gio trnh ny. Gio trnh Qun l cht thi rn th 5CHNG 2 NGUN PHT SINH, KHI LNG,THNH PHN V TNH CHT CHT THI RN TH 2.1 CC NGUN PHT SINH CHT THI RN TH Cng vi s liu v thnh phn v tc pht sinh, ngun v loi cht thi rn l nhng thng s c bn cn thit thit k v vn hnh cc khu lin quan trong h thng qun l cht thi rn. Ngun pht sinh cht thi rn ca mt khu th thay i ty theo mc ch s dng t v cch phn vng. Mc d c nhiu cch phn loi ngun pht sinh cht thi rn th (CTRT)khcnhau,vicphnloiCTRTtheoccngunphtsinhsauythng csdngnht:(1)hgianh;(2)khuthngmi(nhhng,khchsn,siuth, ch,); (3) cng s (c quan, trng hc, trung tm v vin nghin cu, bnh vin,); (4) khu xy dng; (5) khu cng cng (nh ga, bn tu, sn bay, cng vin, khu vui chi giitr,ngph,);(6)trmxlchtthi(trmxlncthisinhhot,...);(7) nh my, x nghip trong khu dn c v (8) vng nng nghip. Trong nhng ngun pht sinh cht thi rn k trn, CTRT l tt c cc loi cht thi rn pht sinh t khu th ngoi tr CTR t sn xut cng nghip (CTR cng nghip). Tuy nhin, cht thi rn y t cqunltheohthngring,do ,trongchng trnh hc ny khng cpn cht thi rn cng nghip v cht thi rn y t. 2.2 KHI LNG, TC PHT SINH CHT THI RN TH 2.2.1 La chn n v biu din khi lng, tc pht sinh cht thi rn Khilngchtthirnsinhravthugomccnghacbitquantrngtrong vic la chn thit b, vch tuyn thu gom, la chn cng ngh v thit k h thng thit b thu hi, x l cng nh thi b CTRT mt cch hp v sinh. V d vic thit k mt loixecbitthugomringccthnhphnchtthicphnloitinguns ph thuc vo khi lng ca tng thnh phn cht thi ny. Quy m, cng sut ca h thngtichchtthiphthucvokhilngchtthithugomccngnhs thay i khi lng cht thi theo thi gian. Cng tng t nh vy, din tch bi chn lphpvsinhsphthucvolngchtthicnlisaukhitchringnhng thnh phn c kh nng ti ch v ti s dng. Tytheomcchqunl,gimsthaytnhtonthitkchotnghngmccth trong h thng qun l CTRT m thng s khi lng CTRT pht sinh hay thu gom s c biu din theo nhng cch khc nhau nh sau: - i vi mt khu dn c (c th l mt thnh ph, qun, huyn, th trn hay mt cm dn c ang xt n nh lng, x, phng, khm, t dn ph,), khi lng CTR pht sinhhaythugomcbiudinbngkhilngCTR/thigiannh:tn/ngy; tn/thng;tn/nm.Trongtrnghpgitrnyrtnh,cthbiudinbng kg/ngy; kg/thng; kg/nm. Bn cnh , cng c th s dng thng s th tch biu Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 6din lng CTR pht sinh hay thu gom tnh (th tch CTR/thi gian) bng m3/ngy; m3/thng;m3/nm.Tuynhin,cnlurngvicsdngthngsthtchxc nh lng CTR c th gy nhm ln v 1 m3 CTR trong thit b lu tr ti ngun (khi cha b nn p) s c khi lng khc vi 1 m3 CTR c p trong xe thu gom v c hai gi tr ny s khc vi khi lng ca 1 m3 CTR tip tc c p bi chn lp. Do,thngsm3CTR/thigianchcnghakhicbiudincngvimc nnphaykhilngringcaCTRtrongiukinlutrtngng.Vvy, trnh nhm ln, lng CTR pht sinh hay thu gom t mt khu dn cnn c biu dindidngkhilngCTR/thigian.Khilnglthngsbiudinchnh xc nht lng CTR v c th cn trc tip m khng cn k n mc nn p. Biu dinbngkhilngcngcnthittrongqutrnhvnchuynvlngCTRc phpchuynchtrnng(theotitrngxe)thngcquynhbigiihn khi lng hn l th tch. - sosnhmcphtsinhCTRgiacckhudnckhcnhautrongcngmt thnh ph, gia cc thnh ph khc nhau trong cng mt quc gia hay gia cc quc gia khc nhau trong cng mt khu vc, vic s dng thng s khi lng CTR/thi gian cha cung cp thng tin v do c th dn n s so snh khp khing. V d s liu A tn CTR/ngy ca khu dn c A so vi B tn CTR/ngy ca khu dn c B ch cho bit trong mt ngy, mi khu dn c ny thi ra mt lng CTR tng ng l A v B tn. Tuy nhin, c th so snh mc pht sinh CTR gia hai khu dn c ny cn phi xem xt thm cc yu t v: dn s, mt dn s (v din tch), khu dn c thucvngnngthnhaythnhth,sliunycthngkvomanotrong nm,Do,thuntinhntrongvicsosnh(cngnhctnhkhilng CTR pht sinh ca mt khu dn c trong tng lai), n v khi lng CTR pht sinh hay thu gom/ngi.ng (kg/ngi.ng) thng c s dng. - Ty theo tng ngun pht sinh CTR khc nhau, tc pht sinh hay thu gom CTR s c biu din sao cho c th so snh, nh gi v c tnh khi lng CTR c d dng v chnh xc nht. + i vi CTR pht sinh t cc khu thng mi (nh ch, siu th,), cch biu din hp l phi th hin c mi lin quan gia khi lng CTR pht sinh hay thu gom vi s lng khch hng, s lng sn phm hoc gi tr bn c, hay mt s n vtngtnhkgCTR/khchhng.ng;kgCTR/triunggitrsnphmbn ra.ng. Bng cch ny cho php so snh cc s liu cc khu thng mi khc nhau trong c nc. + Cht thi rn pht sinh t cc x nghip cng nghip phi c biu din trn n v sn phm nh kg/xe i vi c s lp rp xe hoc kg/ca i vi c s ng gi. S liu ny cho php so snh gia c s c hot ng sn xut tng t trong c nc. + Hu ht s liu v cht thi rn sinh ra t hot ng nng nghip c biu din da trn n v sn phm nh kg phn/kg b v kg cht thi/tn sn phm. Gio trnh Qun l cht thi rn th 72.2.2 Phng php kho st xc nh tc pht sinh cht thi rn Kho st xc nh tc pht sinh cht thi rn t h gia nh Cch thc t chc kho st, o c, ly mu xc nh tc pht sinh t h gia nh sthayitytheomcchsdngsliuthuthpccngnhphngnquy hoch qun l CTRT ca khu vc trong tng lai. n gin v d hiu, trong phn ny s trnh by phng php kho st cho hai trng hp: (1) khng thc hin phn loi CTR ti h gia nh trc khi thu gom v (2) CTR t h gia nh s c phn loi thnh hai thnh phn (rc thc phm v phn cn li) trc khi thu gom. Trng hp 1- Khng thc hin phn loi cht thi rn t h gia nh Cng tc kho st, ly mu xc nh tc pht sinh CTR t h gia nh c th c tin hnh theo cc bc sau y: - Bc 1 Thu thp s liu c s. Thu thp nhng thng tin chung v khu dn c cn kho st bao gm: bn hnh chnh khu vc kho st, din tch, s h gia nh, dn s, mt dn s, s phn b dn c trn a bn (c th xc nh n gin bng thng s bao nhiu phng/qun, s khu ph/phng, s t dn ph/khu ph), khu trung tm, khu nh chut, nh chung c, nh bit th, c im pht trin kinh t x hi trong khu vc.Ccthngs ny gip vicxydngmnglilymuc ngu v th hin tnh c trng ca khu dn c kho st. -Bc 2 - Xy dng mng li kho st ly mu. Mng li kho st ly mu phi c phn b ng u trong ton khu vc kho st v cho php xc nh gi tr c trng theo phng php xc sutthng k. Do,tytheothi gian v kinh ph cho php, s lng mu kho st cng nhiu, chnh xc ca kt qu thu c cng cao. Da trn tng s h gia nh hin c trong khu vc, xc nh s h gia nh cn kho st. Nu tnh theo gi tr ph hp v mt xc sut, s lng h gia nh kho st phi chim khong 30% tng s h hin c trong khu vc. Tuy nhin, cng cn lu rng, ivinhngkhudnclnvitngshdnlnnvichcngnh(vd 35.000h),chcnkhost10%tngshny,slnghgianhcnkhost cng rt ln (trong v d ny l 3.500 h). l cha k, i vi mi h gia nh, vic kho st ly mu cn phi c trng cho cc thi im khc nhau trong tun, gia cctunkhcnhautrongthng,giaccthngkhcnhautrongnmvcbitvo cc dp l tt. V vy, mi khu dn c, s lng h gia nh kho st nu c th b tr t 500-1.000 h l t yu cu. Vi tng s h gia nh phi kho st chn, xc nh s h gia nh phi kho st cho tng khu vc trong khu dn c, c th: s h/phng, s h/khu ph, s h/t dn ph. Nu khng quan tm n c im nh (nh thp tng, nh cao tng, chung c, bit th, nh ng ph chnh, nh cc ng hm, nh gn knh rch,) hay thu nhp (h c thu nhp thp, trung bnh v cao), cc h gia nh kho st s c chn ngu nhin. Nu quan tm n nhng c im k trn, h gia nh kho st tng khu vc phi c thit k sao cho c th ly mu c trng vi cc c im lit k. V trcacchgia nhkhostscchnmtcchtngi da vo mngli Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 8ng ph th hin trn bn v xc nh li a ch chnh xc khi trin khai kho st thc t. -Bc 3-Xc nh chu k kho st ly mu. Khi lng rc pht sinh tng h gia nh s thay i theo sinh hot ca gia nh gia cc ngy khc nhau trong tun, trong thngvnm.Do,khngthcsliuctrngkhichtinhnhlymuphn tch mt ln. Chu k kho st ly mu phi th hin c cc yu t nh hng n tc pht sinh CTR ca h gia nh, c th nh sau: + Sinhhotcangidngiaccngykhcnhautrongtunkhnggingnhau. Nhng ngy lm vic (t th hai n th su) thng khng c nhiu thi gian t chc hp mt gia nh, gp g bn b, nu nng cc mn n c bit, trong khi , iu ny thng xy ra vo nhng ngy ngh cui tun (th by v ch nht). y l mt trong nhng l do lm cho khi lng rc mt s h gia nh vo nhng ngy ngh cui tun s cao hn nhng ngy khc. Tuy nhin, cng c trng hp, cc gia nh t chc i chi xa hoc v qu thm b m, ng b, nn vo ngy cui tun li khng c rc. Bn cnh , cng cn lu rng mt s cn b, cng nhn, vn philmvicsngthbyhaycngythbynnnhiuhgianhcchot ng ny ch tp trung vo ngy ch nht. V vy, khi lng rc pht sinh t cc h gia nh phi c kho st gia ngy lm vic v ngy ngh cui tun. Chu k khostcththchinnhsau:mtngylmvic(cthchnmttrongcc ngytthhainthsu)vhaingycuitun(cthbyvchnht).Nh vy, vi yu t ny, s mu ly mi h gia nh l 3 mu. +Giaccthngmah(manng)vccthngmama,khilngCTRpht sinh t h gia nh cng khc nhau, c bit vo nhng thng l ma ca mt loi tricyno hayvomathuhochthyhisn.Voccthngmama,cc loi thc phm ti sng cng khc v mt phn do thi tit mi th u tr nn t hn,kcrc.Trongtrnghpny,khilngrctnhtrnhgianhtrong ngycthlnhnsoviccngytrongmakh,nhngchyulmcao hn. Vi nhng c im ny, chu k kho st ly mu phi c trng cho cc ma cbittrongnm,tnhtlhaima:makhvmama.Nukhncth kho st theo cc ma tri cy v thu hoch thy hi sn. +Vo nhng thng c l c bit (nh ma ging sinh, l Pht n, quc khnh, quc t lao ng,) hoc tt (tt nguyn n, tt nguyn tiu, tt oan ng, dng lch) thngldpccgianhtchchpmtgianh,bymmccbit.Trong nhngngygipl,tt,gianhthngtngvsinh,sasangnhca,vn tc, nn khi lng CTR pht sinh t h gia nh trong nhng ngy l tt u rt cao so vi ngy thng. l cha k, trong nhng ngy tt c truyn ca dn tc, rc phi c lu li h gia nh t mng 1 tt n ht ngy mng 3 tt, nn khi phi thu gom sau tt, khi lng CTR/h gia nh s cn cao hn nhiu. Do , c c nhng gi tr c trng cho trng hp ny, vic kho st ly mu cng cn c thc hin trong nhng ngy gip l tt v ngy thu gom u tin sau tt. Trong trnghpnycthchnchobatrnghp:dpnoel,gipttnguynnv ngy thu gom u tin sau tt nguyn n. Gio trnh Qun l cht thi rn th 9+Vic kho st ly mu xc nh tc pht sinh CTR t cc h gia nh nn c thchinthngxuyn(hngnm)sliuctnhthng k vctrngc chotnggiaionphttrinkinht,xhi.Tuynhin,tytheokinhphvthi gian c thc hin kho st m gii hn chu k kho st ly mu cho ph hp vi tng giai on thc hin d n. -Bc 4 - Xc nh thi gian ly mu. Trong trng hp CTR khng c tch ring nhng thnh phn d thi ra (rc thc phm) vi cc thnh phn khc, kh c th tn trrctrongnhluhnmtngy.Do,thigiangitinilonngmuvthi gian ly mu phi c b tr sao cho c trng c lng rc sinh ra t h gia nh l 1 ngy. Trong trng hp c phn loi CTR ti h gia nh, thi gian gi ti nilon v ly mu c th lu hn 1 ngy, ty theo phng n phn loi chn. -Bc 5 - Tp hun v chun b dng c kho st. Trc khi tin hnh ly mu thc t, nhn vin kho st cn c tp hun nm r yu cu kho st, chun b y dng c v xc nh c nhng thng tin cn thu thp nh sau: +Bn kho st; +S h gia nh cn kho st ti khu vc do mnh m trch; +Mng li ly mu; +Chu k ly mu; +Nidungcnghilitnghgianhkhost:(1)ach(ghirsnh,tn ng, phng/khm, qun), (2) c im nh (mt tin, hm, cao tng, thp tng, chungc,bitth),(3)sngi/h(nnxcnhrsngidi18tui,t18 n 55 tui v trn 55 tui), (4) nu c th nn hi thm thu nhp ca gia nh, (5) th-ngy-thng-nm v gi gi ti nilon ng mu, (6) th-ngy-thng-nm v gi ly li ti nilon cha CTR v (7) ghi ch ngy ly mu (ma kh, ma ma, ma tri cy, l, tt,). Trong cc thng tin s (1), (3), (5) v (6) l nhng thng tin bt buc; + Chun b ti nilon gi cho cc h gia nh v ghi ch trn tng ti khi h gia nh ng hp tc thc hin vic kho st;+ +Nu khng phi mang mu v phng th nghim hay n ni tp trung phn tch thnhphn(chcnxcnhkhilngCTR/hgianh.nghaykhilng CTR/ngi.ng), mi nhm kho st phi mang theo cn (khong 10-15 kg) cn ti ch ti cha rc ly t cc h gia nh (v CTR sau khi cn ln xe thu gom). Trong trng hp phi xc nh thnh phn CTR, khng cn mang theo cn, ly tt cmuviynhngthngtincnthitghichtrntinilonchamu, mangvphngthnghim,tinhnhcnvphntchthnhphntiphngth nghim. -Bc6-Linhvicquanqunlhnhchnhaphng.Trongtrnghp cnthit(khingidnkhngchuhptcvinhnvinkhost),nhmkhost phi lin h vi y ban Nhn dn Phng ni d kin kho st trnh by k hoch, xin giy gii thiu n tip xc cc t dn ph. Cc t trng v t ph t dn ph s gip nhn vin kho st tip cn ngi dn c d dng hn. Tuy nhin, nhng kho st thc hin cho thy a s ngi dn ng h cc nghin cu ci thin cht lng mi trng nn cng khng my kh khn trong vic tip xc vi ngi dn. Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 10Hnh 2.1 Kho st tc pht sinh rc ti cc h gia nh. Trong trng hp ch cn xc nh khi lng CTR/h gia nh (khng cn xc nh khi lng CTR/ngi.ng), cch n gin nht l i theo xe thu gom, ly rc ca h gianh,cntrctipvlnxe.Khi,nhnvinkhostnnlinhvicng nhn v sinh ca cc t thu gom trc nm r thi gian, tuyn thu gom v c s ng ca cng nhn thu gom. -Bc 7 - Tin hnh kho st. Sau khi thc hin y cc bc 1-6 ni trn, tin hnhgitinilonngmuchocchgianh.Trongthctscmtshgia nh t chi lu tr mu ngay t u v cng c trng hp ng , nhn ti nhng do thiquenhngngy,hkhngchaCTRvotigimvtvonicharc chung ca khu ph, xung knh rch, ao h cnh nh hoc giao cho ngi thu gom khi nhn vin kho st cha kp n ly mu. Do , bo m s lng mu d kin, s h gia nh thc s phi kho st (giti)nnnhiuhnconstnh tonkhong10-20%.Khigitinilon chamuhgianhno,nhnvin khostcnghiliachvthigian hnlymu(trnhtrnghpqunni gi ti n ly mu v trong trng hptxutkhngthnlymu, nhnvinkhostcthnhng nghip i ly h khi c a ch r rng v thigiancth).Ttnht,nngimu vo thi im h gia nh va b rc cho cngnhnthugomvlymuvothi imtrcgithugomrccangy hmsau,cnhvymibomng lng rc cha trong ti gi l lng rc ca mt ngy. -Bc8-Phntchsliu.VikhilngCTRphtsinh/hgianh.ngvs ngi/h, kt qu kho st cho php xc nh tc pht sinh CTR t h gia nh tnh bng kg CTR/ngi.ng, ctrngchongythng,ngycuitun, ngy ltt,cc ma trong nm cng nh gi tr trung bnh cho tt c cc trng hp. Vi hng ngn s liu kho st, c th s dng gi tr ny trong tnh ton thit k h thng qun l CTRTchokhuvc,cnphntchvchnsliuphcvthitk.Phngphp phntchsliuchnhcpdngchotrnghpnylphngphpxcsut thng k, trong cc thng s cn phn tch bao gm:

+Gi tr trung bnh mean; + lch chun; +H s dao ng; + Tn sut xut hin cc gi tr tc pht sinh CTR tnh bng kg/ngi.ng. Trn c s phn tch cc s liu thu thp c theo phng php xc sut thng k, la chngitrtcphtsinhCTRthgianhtnhbngkg/ngi.ngctnsut xut hin cao nht vi lch chun v h s dao ng thp nht l gi tr phc v cho cc tnh ton thit k hay so snh, nh gi tng ng (xem v d 2.1). Gio trnh Qun l cht thi rn th 11V d 2.1 Phn tch s liu kho st theo phng php xc sut thng k Kt qu kho st tc pht sinh CTR t cc h gia nh trn a bn Qun A c trnh by trong Bng 2.1. Hy xc nh thng s tc pht sinh CTR t h gia nh phc v cho cc tnh ton thit k sau ny. Bng 2.1 Kt qu thng k khong gi tr tc pht sinh rc (kg/ngi.ng) trn a bn Qun A v tn sut xut hin cc gi tr ny Tc pht sinh rc (kg/ngi.ng), xi S ln xut hin, fi Tn sut xut hin (%), fi Tc pht sinh rc (kg/ngi.ng), xi S ln xut hin, fi Tn sut xut hin (%), fi0,02-0,10283,831,71-1,8040,55 0,11-0,209512,981,81-1,9150,68 0,21-0,3010314,071,91-2,0000,00 0,31-0,4011816,122,01-2,1000,00 0,41-0,509112,432,11-2,2040,55 0,51-0,60689,292,21-2,3020,27 0,61-0,70425,742,31-2,4000,00 0,71-0,80446,012,41-2,5020,27 0,81-0,90233,142,51-2,6010,14 0,91-1,00324,372,61-2,7000,00 1,01-1,10162,192,71-2,8010,14 1,11-1,2070,962,81-2,9000,00 1,21-1,3091,232,91-3,0000,00 1,31-1,40101,373,01-3,1000,00 1,41-1,50152,053,11-3,2000,00 1,51-1,6030,413,31-3,4000,00 1,61-1,7070,963,41-3,5020,27 Bi gii -Da trn s liu trnh by trong Bng 2.1, v biu s phn b tn sut khong gi tr tc pht sinh CTRSH (kg/ngi.ng) t h gia nh trn a bn Qun A (Hnh 2.2). Kt qu kho st v phn tch s liu cho thy tc pht sinh rc h gia nh trn a bnQunAtnhtheokg/ngi.ngdaongt0,02-3,50kg/ngi.ng.Nutnhtheo cc khong gi tr nh trnh by trong Hnh 2.2, tc pht sinh rc trn a bn Qun A mc0,30-0,40kg/ngi.ng.ylnhngkhonggitrctnsutxuthincao nht trong tp s liu kho st (118 ln so vi 732 ln kho st, chim 16,12%). Nu tnh trung bnh (mean), gi tr tc pht sinh rc t h gia nh trn a bn Qun A l: Mean = n x fxi i= = 0,567 ~ 0,57 kg/ngi/ng Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 12 0246810121416180.02-0.10.21-0.30.41-0.50.61-0.700.81-0.91.01-1.101.21-1.301.41-1.501.61-1.701.81-1.912.01-2.102.21-2.302.41-2.502.61-2.702.81-2.903.01-3.13.31-3.40kg/ngi/ngyTn sut (%)Gio trnh Qun l cht thi rn th 13Hnh 2.2 S phn b tn sut khong gi tr tc pht sinh CTRSH (kg/ngi.ng) t h gia nh trn a bn Qun A. Trong , fi l tn sut xut hin gi tr xi. lch chun ( )46 , 01 73294 , 15212== =nx x fsi ikg/ngi/ng H s dao ng % 8057 , 046 , 0 100 100===xsCV Gitrlchchun(standarddeviation)s=0,46kg/ngi/ngvhsdaong (coefficient of variation) CV = 80% cho thy tr s kho st c dao ng rt ln. iu nychothycncnhiu yut khch quannh hngn kt qu khostmcha c kim sot. Cc gi tr ny, mt ln na cho thy cn xc nh cc iu kin bin c th khi tin hnh kho st v nh gi kt qu thu thp. Khi tin hnh kho st khi lng rcphtsinhtcchgianh,nhmkhostlymungunhinnhnghgia nh c giao rc cho ngi thu gom hay ng cho cn rc. Do , tp s liu thu thp c khng th hin r cc yu t nh hng nh (1) mc thu nhp ca gia nh, (2) t l rc pht sinh so vi rc giao li cho ngi thu gom (do t, chn, thng rc dc ng,bnphliuvkhngbnphliu,),(3)cctrunghpcbitnhct chc tic tng, tng v sinh nh ca,Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 14Trng hp 2- Cht thi rn t h gia nh c phn loi thnh hai thnh phn Trong trng hp vic kho st xc nh tc pht sinh CTR t h gia nh (tnh theo kg/ngi.ng) phc v cho quy hoch, tnh ton thit k h thng qun l CTRT theo chngtrnhphnloiCTRTtingun(PLCTRTTN),phngphpkhostly mu s c mt s im khc vi trng hp 1. Trnh t thc hin kho st ly mu vn phi tun theo 7 bc k trn. Trong cc bc 1, 2, 3, 5, 6 v 8 s ging nh trng hp 1. Ring bc 4 v bc 7 s phi thay i cho ph hp vi hnh thc phn loi. -Bc4-Xcnhthigianlymu.TrongtrnghpCTRtihgianhc phnloithnh2thnhphn:rcthcphmvphncnli,cnc2ticharc ring cho mi thnh phn. Nu ch gi mt ti cha rc hn hp, sau mang mu v phng th nghim mi tin hnh phn loi xc nh khi lng ca tng thnh phn, kt qu s khng chnh xc. Nguyn nhn chnh l do khi cha rc hn hp, cc thnh phn rc kh nh giy, bo, vi, g, ti nilon, tro, s b thm nc t rc thc phm v dnh nhng mu vn rc thc phm. Do , khi phn loi thnh 2 thnh phn (rc thc phm v phn cn li) v cn xc nh khi lng, khi lng cc thnh phn cn li s c gi tr cao hn gi tr thc ca chng. l cha k cc phn tch v m, khi lng ring v t l phn trm ca tng thnh phn c trong rc cng khng c chnh xc. Do , thit k h thng qun l CTR theo hng PLCTRTTN, khi kho st s liu phc v cho tnh ton thit k, phi gi t nht 2 ti nilon cha mu rc t nht thnh 2 thnh phn ring bit. Thi gian gi ti, ly mu 2 thnh phn ny cng s khc nhau ty thuc nhng yu t sau: +Ty theo phng n thu gom la chn (thu gom 1 ln/ngy i vi c 2 thnh phn hoc ch thu gom 1 ln/ngy i vi rc thc phm v 3 ln/ngy i vi phn cn li). i vi rc thc phm - thnh phn d thi ra nn chu k thu gom vn phi thugomtheochuk1ln/ngy(cbitnhngncthucvngkhhunhit i,nngmnhVitNam.Tuynhin,cngcnluccncckhhun i, thnh phn rc thc phm thng cha tp trung c thu gom theo chu k di hn,cth1ln/tun).Nhvytinilongihgianhlymurcthc phm s c sp xp c th ly mu c trng l lng rc thc phm pht sinh thgianhtrongmtngy.ivithnhphncnli,dotnhchtkhphn hy hn, kh ro hn nn t gy mi hi thi hn so vi rc thc phm. Thm vo ,thnhphnnyckhilngthnnnthngkhngcnthitthugommi ngy mt ln. Cch tt nht l chn thi gian gi ti v ly mu bng thi gian ca chu k thu gom s c thit k (v d 2 ngy/ln hay 3 ngy/ln). +Tytheokhilngvctnhcalngrcphnloichnthigianph hp.Khngkthnhphnrcthcphm(vncta,thnhphnnybtbuc phi thu gom mi ngy mt ln), thnh phn rc cn li thng rt t v khc nhau rtnhiu gia cc ngy khc nhau. Do, muthu c c khilngln, cho php cn xc nh khi lng v thnh phn, thi gian gi ti ly mu h gia nh nn t 2-3 ngy. Tuy nhin cng cn lu rng do phn rc cn li khng hon ton kh nn nu lu tr lu trong nh vn to mi hi kh chu. Nhng t kho st thc hin cho thy ngi dn khng thch lu tr phn rc cn li lu hn 2 ngy. y cng l yu t cn lu trong tnh ton thit k. Gio trnh Qun l cht thi rn th 15-Bc 7 - Tin hnh kho st. Sau khi thc hin y cc bc 1-6, tin hnh gi ti nilon ng mu cho cc h gia nh. i vi ti cha rc thc phm, sau 1 ngy, nhn vin kho st n ly ti cha mu, cn trc tip v b rc ln xe thu gom, khng cnmangvphngthnghim.ivitichathnhphncnli,sau2(hoc3 ngy),nhnvinkhostnlytichamuvmangvphngthnghim(hoc ni tp trung) xc nh khi lng v phn tch xc nh thnh phn phn trm ca tng loi. Kho st xc nh tc pht sinh cht thi rn t trng hc Cht thi rn t trng hc pht sinh do hai ngun chnh: (1) rc t lp hc (ch yu l giy nhp ca hc sinh, sinh vin) v sn trng (l cy) v (2) rc t cntin ca trng. Vic kho st tc pht sinh CTR t trng hc cn c tin hnh vi cc i tng sau: (1) nh tr; (2) trng mm non; (3) trng tiu hc, trung hc c s (cp 1, 2); (4) trng trung hc ph thng (cp 3), (5) trng cao ng, trung hc chuyn nghip v i hc, (6) trung tm ngoi ng/tin hc v (7) c s dy ngh. Cng tc kho st, ly mu xc nh tc pht sinh CTR c th c tin hnh theo cc bc sau y: - Bc1Thuthpsliucs.Thuthpnhngthngtinchungvslng,a ch,quym,loihnhcacctrnghchinctrongkhuvc.Ccthngsny gip vic xy dng mng li ly mu c ng u v th hin tnh c trng ca cc trng hc trong khu vc kho st. -Bc 2 - Xy dng Mng li ly mu. Da trn s trng (theo tng loi hnh) hin c trong khu vc, xc nh s trng cn kho st. mi qun/huyn, tng s trng hc thng mc hng trm tr xung. Do , s lng kho st c th ly 30% tng strnghinc.Trongtrnghpslngnykhngnhiu(khongvichc trng), nn tin hnh kho st cho tt c cc trng. -Bc 3 - Xc nh chu k kho st. Khi lng CTR pht sinh s thay i theo c im ca tng trng. Do , khng th c s liu c trng khi ch tin hnh ly mu phn tch mt ln. Chu k kho st ly mu phi th hin c cc yu t nh hng n tc pht sinh CTR ca tng i tng trng hc, c th nh sau: +Ty theo tng loi trng m s lng hc sinh, sinh vin n hc ti trng s thay i theo cc ngy khc nhau trong tun. nhng trng mm non, mu gio, thi gian hot ng ca trng thng t 6-7 gi sng n 4-5 gi chiu, t th hai n th su hng tun, th by v ch nht trng ngh v s lng tr em c gi ylcnh.Nhvy,khilngCTRphtsinhnhngdngtrngnys tng i n nh gia cc ngy lm vic trong tun v ch khc vo ngy cui tun. Trongkhi,cctrngtiuhc,trunghccs,trunghcphthng,kc nhngtrngcaong,trunghcchuynnghipvihc,ngoigihcchnh cahcsinh,sinhvintrongtrng(theohaibuisngvchiu),vobuitiv ngychnht,cccsnythngchothuaimdyngoing,vitnh, luyn thi i hc, v thut hoc cc kha hc khc. S lng hc vin n trng s khc nhau gia cc ngy khc nhau trong tun. y l mt trong nhng yu t lm chokhilngCTRphtsinhcctrngskhcnhau.Do,chukkhost nn thc hin nh sau: hai ngy lm vic (c th chn mt trong cc ngy t th hai Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 16n th su) v hai ngy cui tun (th by v ch nht). Nh vy, vi yu t ny, s mu ly mi trng l 4 mu. +Giaccthngcahckvccthngmah,slnghcsinh,sinhvinn trngsrtkhcnhau.Do,khilngCTRphtsinhcctrngcngs khc nhau, nht l nhng trng hc bn tr. Vi c im ny, chu k kho st ly mu phi c trng cho t nht hai giai on: mt trong hai hc k chnh v ma h. + mi trng, phi xc nh khi lng CTR t lp hc, sn trng v khi lng CTR t cc cntin trong trng. +Vic kho st ly mu xc nh tc pht sinh CTR t trng hc cng nn c thchinthngxuyn(hngnm)sliuctnhthng k vctrngc cho tng giai on pht trin ca trng. Tuy nhin, ty theo kinh ph v thi gian c thc hin kho st m gii hn chu k kho st ly mu cho ph hp vi tng giai on thc hin d n. -Bc 4 - Xc nh thi gian ly mu. i vi CTR t cntin trong trng, thi gian gitivlymucthchintngtnhtrnghpkhostCTRthgia nh khi khng cng nh c phn loi CRT ti ngun (tc l 1 ngy i vi mu CTR hn hp hay mu rc thc phm v 2-3 ngy i vi phn rc cn li). i vi rc t lphcvsntrng,chyuchcgiyvn,lcy,cngnhtinilon,vhp ngthcung,chaipet,cchatrongccthngrccngcngxungquanh trng vi khi lng mi ngy tng i nhiu, nn thi gian gi ti v ly mu c th thc hin trong 1 ngy (cho c hai trng hp c v khng PLCTR ti ngun). -Bc 5 - Tp hun v chun b dng c kho st. Trc khi tin hnh ly mu thc t, nhn vin kho st cn c tp hun nm r yu cu kho st, chun b y dng c v xc nh nhng thng tin cn thu thp sau y: +Bn kho st; +S trng hc cn kho st ti khu vc do mnh m trch; +Mng li ly mu; +Chu k ly mu; +Nidungcnghilitngtrngkhost:(1)ach(ghirs,tnng, phng/khm,qun),(2)loihnh(nhtr,mmnon,tiuhc,trunghccs, trunghcphthng,caong,trunghcchuynnghip,ihc,trungtmngoi ng/tin hc, c s dy ngh), (3) c im (trng hc 2 ca, 3 ca, bn tr, khng bn tr,chccuitunvbanm),(4)shcsinh/sinhvin/hcvinntrng trong mt ngy m (nu c th, xc nh r s hc sinh, sinh vin chnh thc hc ca ngy v shc vin hccamvchnht),(5)slngcnbcngnhn vinlmvictitrng,(6)scntinctrongtrng,(7)th-ngy-thng-nmv gi gi ti nilon ng mu, (7) th-ngy-thng-nm v gi ly li ti nilon cha CTR v (8) ghi ch ngy ly mu (hc k 1, hc k 2, ma h).+ Chun b ti nilon gi cho cn-tin ca trng (1 hoc 2 loi ti ty phng n khng hoc c PLCTR ti ngun) cng nh ti nilon c kch thc ph hp i vi tt c cc thng cha rc cng cng xung quanh trng v ghi ch trn tng ti trnh nhm ln. Gio trnh Qun l cht thi rn th 17+Nu khng phi mang mu v phng th nghim hay n ni tp trung phn tch thnh phn (ch cn xc nh khi lng CTR/trng.ng hay khi lng CTR/hc sinh.ng), mi nhm kho st phi mang theo cn (khong 15-20 kg) cn ti ch ticharclyttrng(vCTRsaukhicnlnxethugom).Trongtrng hpphixcnhthnhphnCTR,khngcnmangtheocn,lyttcmuvi y nhng thng tin cn thit ghi ch trn ti nilon cha mu, mang v phng th nghim, tin hnh cn v phn tch thnh phn ti phng th nghim. -Bc 6 - Lin h vi c quan qun l hnh chnh a phng. Nhm kho st nn lin h vi S Gio dc nm r tnh hnh ca cc trng trn a bn kho st, trnh by khochthchin v xin giithiu nlmvicvitngtrngtrckhitin hnh kho st. Trong trng hp ch cn xc nh tng khi lng CTR/trng (khng cn xc nh khi lng CTR/hc sinh.ng), cch n gin nht l i theo xe thu gom, cng ly rc, cntrctipvlnxe.Khi,nhnvinkhostnnlinhvicngnhnv sinh ca cc t thu gom trc nm r thi gian, tuyn thu gom v c s ng ca cng nhn thu gom. -Bc 7 - Tin hnh kho st. Sau khi thc hin y cc bc 1-6 ni trn, tin hnh gi ti nilon ng mu cho cntin v n cc thng cha rc cng cng ca tng trng. Ly mu v phn tch tng t nh trng hp CTR pht sinh t h gia nh trnh by trn. -Bc 8 - Phn tch s liu. Phn tch s liu tng t nh trng hp CTR pht sinh thgianhvtnhthnhnvkhilngCTRphtsinh/trng.ngvkhi lng CTR/hc sinh (sinh vin).ng. Kho st xc nh tc pht sinh cht thi rn t cng s CcbctinhnhkhostxcnhtcphtsinhCTRtcngscthchin tngtnhiviCTRthgianh.Tuynhin,ivibc5cnluccni dung sau y: - Nidungcnghilitngcngskhost:(1)ach(ghirs,tnng, phng/khm,qun),(2)cim(ccn-tin,khngccntin),(3)scnbcng nhn vin lm vic ti cng s, (7) th-ngy-thng-nm v gi gi ti nilon ng mu, (7) th-ngy-thng-nm v gi ly li ti nilon cha CTR v (8) ghi ch ngy ly mu (ngy trong tun, ngy th by). - Chun b ti nilon gi cho cntin (1 hoc 2 loi ti ty phng n khng hoc c PLCTR ti ngun) cng nh ti nilon cha CTR vn phng v ghi ch trn tng ti trnh nhm ln. Kho st xc nh tc pht sinh cht thi rn t ch Tm bc tin hnh kho st xc nh tc pht sinh cht thi rn t ch s c trin khaitngtnhivitrnghpCTRphtsinhthgianh.Tuynhin,trong trng hp ny cn lu nhng im sau y: Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 18 - S lng ch c trn a bn mt qun khng nhiu (so vi cc ngun pht sinh CTR khc) v ch c th xc nh bng tng khi lng CTR/ngy (khng th quy i theo ssp,theoslnghnghabnrahoctngdoanhthuvphthucvonhiu thnh phn tham gia bun bn ti ch), do , phng php n gin nht l kho st ti im tp trung CTR chung ca ch. - iviccchbnccmthnglngthc,thcphm,hotngbunbnvo ngy cui tun (th by, ch nht) v nhng dp l, tt cng nh ma tri cy s nhiu hn nhng ngy thng. Do , chu k kho st phi c trng cho: + Ngy thng v ngy cui tun (th by, ch nht); + Cc dp l, tt; + Cc ma tri cy. - Phng php kho st chnh l theo xe thu gom, vn chuyn CTR ca ch n ni xe rc ( trm trung chuyn hoc bi chn lp) c th xc nh khi lng ti trm cn. - i vi cc ch bn cc mt hng in, in t, ch vi, nhng ch khng c im tptrungCTR,lng CTR pht sinh khng nhiunh cc chbnhnglngthc, thcphm,dophigitinilonlymuchotngsptrongchlymuxc nh khi lng. Kho st xc nh tc pht sinh cht thi rn t siu th Tm bc tin hnh kho st xc nh tc pht sinh cht thi rn t siu th s c trinkhaitngtnhivitrnghpCTRphtsinhthgianh.Tuynhin, trong trng hp ny cn lu nhng im sau y: - Slngsiuthctrnabnmtqunkhngnhiu(soviccngunphtsinh CTR khc), nhiu thnh phn CTR c kh nng ti sinh, ti ch c lu tr ring bn li, cn li l CTR t khu vc bn hng n ung. Tuy nhin, trong trng hp ca siu th, c th thu thp c thng tin v tng gi tr mt hng bn ra mi ngy (tnh bng VND/ngy) nn kt qu kho st c th tnh bng n v tn/gi tr bn ra/ngy. Trn c s c th so snh hoc c tnh cho cc siu th khc. - Tng t nh ch, hot ng bun bn cc siu th s tp trung nhiu hn vo nhng ngy cui tun v dp l tt. Do , chu k kho st phi c trng cho: + Ngy thng v ngy cui tun (th by, ch nht); + Cc dp l, tt. - Nhnvinkhostcnlinhvibanqunlsiuthnmckhilngv thnh phnCTRcthtichvtis dngc thu gom v lutrring. i vi phn CTR cn li, phng php kho st chnh l cn ti ni tp trung rc ca siu th. Gio trnh Qun l cht thi rn th 19Kho st xc nh tc pht sinh cht thi rn t nh hng Cc bc tin hnh kho st xc nh tc pht sinh CTR t nh hng c thc hin tngtnhiviCTRthgianh.Tuynhin,ivibc5cnluccni dung sau y: - Nidungcnghilitngnhhngkhost:(1)ach(ghirs,tnng, phng/khm,qun),(2)cim(qunn,nhhng),(3)sltkhchnnh hng mi ngy, (4) s nhn vin phc v ti nh hng; - Chun b ti nilon gi cho nh hng (1 hoc 2 loi ti ty phng n khng hoc c PLCTR ti ngun). Kho st xc nh tc pht sinh cht thi rn t khch sn Cc bc tin hnh kho st xc nh tc pht sinh CTR t khch sn c thc hin tngtnhiviCTRthgianh.Tuynhin,ivibc5cnluccni dung sau y: - Nidungcnghilitngkhchsnkhost:(1)ach(ghirs,tnng, phng/khm, qun), (2) c im (nh tr, khch sn thng, khch sn 3 sao, khch sn 4 sao, khch sn 5 sao, (3) s phng c trong khch sn (loi 1 ging, 2 ging, 3 ging) v s khch c mt ti khch sn mi ngy (tnh trung bnh), (4) s nhn vin phc v ti khch sn. - Chun b ti ph hp gi ti phng ca khch v ti khu cn-tin. Ly mu mi ngy 1 ln (phng n khng hoc c PLCTR ti ngun). Kho st xc nh tc pht sinh cht thi rn ng ph Cht thi rn ng ph pht sinh do l cy dc ng v rc do ngi i ng thi b (khng phi rc do cc h gia nh b ra trc nh). Do , trong trng hp ny, kt qu khostxcnhtcphtsinhCTRngphphthucrtnhiuvohnhthc qut v thu gom CTR ng ph cng nh cch thc ngi dn s dng cc thng cha CTR t cc h ph. Nu da trn s liu khi lng CTR t t qut ng cng nh t cc thng cha rc dc ng ph nh hin nay, kt qu thu c s b sai s rt ln. Do , c th kho st chnh xc khi lng CTR t ngun pht sinh ny, bc u tincnthchinlchnkhuvcthim(khngbrctrcnhvogiqutrc ng)vkhngbrcthgianhvothngcharcdcngph.Khi,8 bc hnh kho st s tng t nh trnh by trn, tuy nhin: -KhilngCTRt qutng phs cotheotng khilngcha trong xe thu gom sau khi qut sch mt din tch ng nht nh (tnh cho tt c cc ln qut cng din tch ng ny trong ngy). Nh vy tc pht sinh CTR t qut ng c tnh bng kg CTR/m2.ng; -i vi CTR do khch i ng b vo cc thng cha dc ng s c xc nh bng cch cn khi lng CTR t xe thu gom rc ca cc thng cha dc ng ny. Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 20TcphtsinhCTRsctnhbngtnCTR/mlng.ng.Cngcnlu rng kt qu kho st trong trng hp ny ch c th so snh c khi mt thng cha CTR dc cc tuyn ng c b tr nh nhau trn ton a bn kho st. Kho st xc nh tc pht sinh cht thi rn ca mt khu dn c TrongtrnghpkhngquantmnkhilnghaytcphtsinhCTRtcc ngunkhcnhau(chcnxcnhtcphtsinhCTRchungcamtkhu/cmdn c), phng php kho st s n gin hn rt nhiu. Bc 1 - Xc nh tt c nhng ni tip nhn CTR ca khu dn c. Nhng ni tip nhn CTR sau khi thu gom ca khu dn c ch yu l bi chn lp (hay khu lin hp x l CTR), cng c th c trm phn loi tp trung hay nh my ch bin compost khi CTR c phn loi ti ngun. Bc 2 - Lin h vi n v qun l cc im tip nhn CTR. Nhm kho st s phi lin h trc vi ban qun l cc im tip nhn CTR k trn nm c nhng thng tin chung sau y: -CTR c thu gom trn a bn no; -Thi gian CTR c vn chuyn n ni tip nhn; -Tng khi lng CTR trung bnh a v mi ngy; -Xin s liu thng k v xin c kho st trong mt khong thi gian nh. Bc 3 - Xc nh chu k kho st. Vic kho st nn c thc hin cho th hin c tt c cc yu t nh hng n tc pht sinh CTR ca khu dn c nh phn tch trn: -Giaccngykhcnhautrongtun(ngylmvicvngycuitunthbyv ch nht); -Ma nng v ma ma; -Ma tri cy c bit; -Dp l, tt. Bc 4 - Tp hun. Nhn vin kho st s c tp hun nm r nhng ni dung cn thu thp sau y: -Ghi r, th, ngy-thng-nm, gi, loi xe, bin s xe v khi lng cn xe vo v ra bi chn lp/trm phn loi/nh my ch bin compost; -ThigiankhosttrongngylthigianxevnchuynmangCTRnbichn lp/trm phn loi/nh my ch bin compost; -Ghi ch c im ca ngy kho st (ngy nng, ma, ngy l, tt,). Bc5-Phntchsliu.NidungbcnycthchintongtnhBc8- Trng hp kho st tc pht sinh CTR t h gia nh. Kt qu kho st s c tnh bng tn CTR/ng. Gio trnh Qun l cht thi rn th 212.2.3 Phng php d on khi lng v tc pht sinh cht thi rn Phng php d on khi lng (hay tc pht sinh) CTR ca mt khu dn c trong tng li c c tnh da trn s liu thng k khi lng (hay tc pht sinh) CTR trong nhng nm trc . Tuy nhin, cn lu rng thng s liu thng k hin c cc c quan qun l ch th hin c khi lng CTR thu gom c (trong mt n v thi gian) ch khng phi lng CTR thc s pht sinh. Ty theo nng lc thu gom CTR ca tng a phng m mc sai khc gia tc pht sinh v tc thu gom s khc nhau kh nhiu, c bit l nhng khu nh ven knh rch, sng, o v vng nng thn. Nu c c tp s liu thng k qua cc nm cho tng ngun pht sinh CTR khc nhau, vic d on khi lng v tc pht CTR i vi tng ngun trong tng lai s thc hinc.Trili,chcthdontngkhilng(haytcphtsinhCTRtng cng)catonkhuvcvdatrntlCTRdotngngunphtsinhgyra(sovi tnglngCTRcackhuvc)nmhintictnh.ngin,trongMc 2.2.3ch trnh by phng php d on khilng(tcphtsinh)CTRchungca mt khu dn c. Cc bc thc hin bao gm: Bc 1 Thu thp s liu Cc s liu cn thu thp bao gm: - Thng k dn s trong khu vc qua cc nm (tt nht l trong vng 10 nm gn nm hin ti nht); - Thng k tc pht sinh CTR ca khu vc (tnh bng tn/ng) trong vng 10 nm; - Quy hoch pht trin dn s, kinh t, x hi ca khu vc trong tng lai (n nm d kin tnh ton, t nht l 10 nm). Bc 2 D on dn s ca khu vc trong tng lai Hin nay c nhiu phng php c tnh dn s ca mt khu vc trong tng lai. Mi phng php u c thc hin vi gi thit ring v chu sai s nht nh. Do , sau khi tnh ton, cn so snh, la chn phng n ph hp (t sai s nht) s dng s liu c tnh lm thng s thit k. Phng php 1 - Gi s tc gia tng dn s l hng s t k l hng s tc gia tng dn s, P l dn s (ngi), t l thi gian (nm), phng trnh tc gia tng dn s ca mt khu vc c biu din nh sau: kdtdP=hay dP = k.dt Ly tch phn hai v phng trnh trn theo thi gian, ta c: } }==ttPPdt k dPt00 0.hay Pt P0 = k.(t t0) hay Pt = P0 + kt Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 22Datrnsliuthngkdnsquaccnm,vngbiudinPt=P0+ktxc nhhskvP0.Vihaigitrnycthctnhdnsnmthtbtktrong tnglai.Tuynhin,phngphpnycnhcimlkhngquantmntlt, n cc iu kin pht trin kinh t, x hi cng nh quy hoch ca khu vc trong tng lai. Phng php 2 - Gi s tc gia tng dn s t l thun vi dn s hin ti t k l hng s tc gia tng dn s, P l dn s (ngi), t l thi gian (nm), phng trnhtc giatng dn sca mt khu vctrongtrng hp ny cbiudin nh sau: P kdtdP. =haydt kPdP. =

Ly tch phn hai v phng trnh trn theo thi gian, ta c: } }==ttPPdt kPdPt00 0.hay lnPt lnP0 = k.(t t0) hay lnPt = lnP0 + kt Da trn s liu thng k dn s qua cc nm, v ng biu din lnPt = lnP0 + kt xc nhhskvP0.Vihaigitrnycthctnhdnsnmthtbtktrong tng lai. Tuy nhin, phng php ny c nhc im l khng quan tm n quy hoch ca khu vc trong tng lai. tg = k P (ngi) t (nm) P0 tg = k LnP Thi gian (nm) lnP0 Gio trnh Qun l cht thi rn th 23Phngphp3-Gistcgiatngdnstlthunvidnshintivc xem xt n quy hoch trong tng lai t k l hng s tc gia tng dn s, P l dn s (ngi), Ps l dn s ti a (theo quy hoch ca khu vc trong tng lai), t l thi gian (nm), phng trnh tc gia tng dn s ca mt khu vc trong trng hp ny c biu din nh sau: ) .( . P P P kdtdPs =hay ( )dt kP P PdPs..=

Tng t, ly tch phn hai v phng trnh trn theo thi gian xc nh h s tc gia tng dn s v t c th c tnh dn s mt nm bt k trong tng lai. Phng php 4 c tnh dn s trong tng lai theo t l gia tng dn s r Dn s mt nm bt k trong tng lai cn c th c tnh theo t l tng dn s r, s dng phng trnh sau: Pn = P0.(1 + r)n Trong , Pn l dn s nm th n k t nm chn lm gc (nm 0), P0 l dn s nm chn lm gc, r l t l tng dn s v n s nm tnh ton (so vi nm chn lm gc). Bc 3 D on khi lng (tc pht sinh) CTR trong tng lai Phng php 1 - Gi s tc gia tng khi lng CTR/nm l hng s Githitnykhngknnhhngcasgiatngdnscngnhiukinpht trin kinh t x hi, quy hoch ca khu vc trong tng lai. Nu gi k l hng s tc gia tng khi lng CTR, m l khi lng CTR/nm, t l thi gian (nm), phng trnh tc gia tng khi lng CTR ca mt khu vc c biu din nh sau: 'kdtdm=hay dm = k.dt Ly tch phn hai v phng trnh trn theo thi gian, ta c: } }==ttmmdt k dmt0,0 0. hay mt m0 = k.(t t0) hay mt = m0 + kt Da trn s liu thng k khi lng CTR ca khu vc qua cc nm, v ng biu din mt = m0 + kt xc nh h s k v m0. Vi hai gi tr ny c th c tnh khi lng CTR ca khu vc nm th t bt k trong tng lai. Cng vi s liu c tnh dn s ca khu vc qua cc nm, c th d on tc pht sinh CTR tnh bng kg/ngi.ng nhng nm trong tng lai. Hoc ngc li, da trn s liu thng k v dn s v khi lng CTR ca cc nm trc, tnh tc pht sinh CTR(kg/ngi.ng)vsdngsliunyctnhtcphtsinhCTRtheo Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 24kg/ngi.ng nhng nm trong tng lai. Ly gi tr kg CTR/ngi.ng nhn vi dn s d on nm tng ng c tnh tng khi lng CTR ca khu vc. Phng php 2 - Gi s tc gia tng khi lng CTR/nm t l vi khi lng CTR ca nm hin ti Vigithitny,phngphp2cxemxtncimcanmhintid onlngCTRsphtsinhcanhngnmktip.Nugiklhngstcgia tng khi lng CTR, m l khi lng CTR/nm, t l thi gian (nm), phng trnh tc gia tng khi lng CTR ca mt khu vc c biu din nh sau: m kdtdm.'=haydt kmdm.'= Ly tch phn hai v phng trnh trn theo thi gian, ta c: } }==to tmmdt kmdmt00.'hay ln(mt) ln(m0) = k. (t-t0) hay ln(mt) = ln(m0) + k.t Da trn s liu thng k khi lng CTR ca khu vc qua cc nm, v ng biu din ln(mt) = ln(m0) + k.t xc nh h s k v m0. Vi hai gi tr ny c th c tnh khi lng CTR ca khu vc nm th t bt k trong tng lai. Tng t nh phn tch trn, bng phng php ny kt hp vi s liu d on dn s c th c tnh tc pht sinh CTR theo kg/ngi.ng hay ngc li da trn s liu thng k tc pht sinh CTR (kg/ngi.ng) c tnh khi lng CTR ca khu vc trong tng lai (tn/nm). 2.3 THNH PHN CHT THI RN TH Bn cnh thng s khi lng, thnh phn CTR l mt trong nhng thng s c ngha quantrngtrongviclachnphngncngnghthugom,xlvthibhpv sinh CTR ca mt khu vc. Thnh phn v phng php phn tch thnh phn CTRTl ni dung chnh c gii thiu trong phn ny. 2.3.1 Thnh phn cht thi rn th Trongchtthirnthcchanhiuthnhphnkhcnhau,thngthnggmc : rc thc phm, giy loi, bao b carton, ti nilon, nha, vi, cao su, da, g, thy tinh v, snhs,ccloichailbngthytinhhocbngnha,lonhp,lonnc,Ty theomcchvphngnkthutqunlchtthirntngunphtsinhnni thi b cui cng, thnh phn cht thi rn c th c biu din t rt n gin (ch gm 2thnhphnchnh:(1)rcthcphmv(2)phncnli)hocrtchitit(gmtng thnh phn ring bit nh k trn hoc chi tit hn). i vi cc nc Chu , rc thc phm(hocthnhphnchthucckhnngphnhysinhhc)lthnhphn thng chim t l cao nht (thng dao ng trong khong 50-70% tnh theo khi lng Gio trnh Qun l cht thi rn th 25t) trong CTRT. Thnh phn CTRT thay i rt nhiu theo c im vn ha, iu kin kinh t, x hi v c im h thng qun l cht thi rn hin ti ca a phng. 2.3.2 Phng php phn tch thnh phn cht thi rn VthnhphnCTRctnhbng%khilngt(sovitngkhilngcahn hpphntch),nngitr%nysthayirtnhiutytheomcatngthnh phn trong mu. Vi cc mu CTR hn hp (cha chung trong thng hoc ti nilon), cc thnhphngiy,vi,g,tro,rtdbthmnctrcthcphmvlmchokhi lng t ca tng thnh phn ny cao hn so vi khi lng thc ca chng. Do , khi ly mu phn tch thnh phn CTR cn lu yu t ny. i vi nhng ngun pht sinh cht thi rn c khi lng nh Nhng ngun pht sinh CTR c khi lng nh bao gm t h gia nh, cng s, trng hc,nhhng,khchsn.KhilngCTRphtsinhtnhngngunnymingy khng nhiu (tnh bng kg/ngun.ngy). Do , mu c ly ring, phn tch ring cho tng i tng v tt nht l gi ti nilon cha ring rc thc phm (thnh phn c m) v cc thnh phn cn li. Chu k ly mu, xy dng mng li ly mu v phn tch sliutngt nh trnhbytrongphnkhostxcnhkhilng(tc pht sinh)CTRMc2.2.2.Thngthng,vickhostkhilngvthnhphnc thchincngmtlc.Do,saukhily muxcnh khi lngCTRphtsinh trong mt n v thi gian nht nh, mu ny c tip tc phn tch thnh phn cng nh cc c tnh l hc, ha hc v sinh hc khc. Mu CTR ly t h gia nhTch ring tng thnh phn Hnh 2.3 Xc nh thnh phn CTR t h gia nh. Rc thc phm c cha ring s gip cng tc phn tch cc thnh phn cn li c n gin, d thc hin hn v cho kt qu chnh xc hn. i vi rc thc phm ch cn cnxcnhkhilng.Muchaccthnhphncnlicphnloi(bngtay) ringtngthnhphnnhgiy,carton,nilon,nha,vi,caosu,da,g,thytinh,kim loi, lon hp, snh s, tro, Ty theo mc ch xc nh thnh phn CTR m mc phn loi c th k hn. V d, i vi giy c th phi phn bit giy bo, tp ch, giy tp hc sinh, giy vn phng, giy gi hng, hay nha phi phn loi thnh nha PE, Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 26PVC, PS, HDPE, LDPE, Sau khi phn loi, tin hnh cn khi lng v tnh t l ca tng thnh phn so vi tng khi lng CTR ca ngun kho st. Hnh 2.4 Mt s thnh phn CTR phn loi. i vi nhng ngun pht sinh cht thi rn tp trung NhngngunphtsinhCTRtptrungbaogmch,nhmyhaytinhngimtp trung CTR nh trm trung chuyn, bi chn lp, CTR c hn hp, do , phi ly mu hn hp phn tch. Nh vy kt qu s rt sai lch do nhiu thnh phn CTR b nhim bn v ht m bi rc thc phm. Trong trng hp ny, mu phn tch c khi lng cng ln cng tt, t nht t 100-200 kg/mu. Tng t nh trnh by trn, thnh phn CTR c phn loi bng tay v cn xc nh khi lng ca tng loi ring bit:rcthcphm,giy,carton,nhacng,nilon,vi,caosu,da,kimloi,...Thnh phnphntrmcatngloictnhtondatrnkhilngcatngloisovi tng khi lng mu phn tch. 2.4 TNH CHT L, HA, SINH CA CHT THI RN TH 2.4.1 Tnh cht l hc Khi lng ring Khi lng ring c nh ngha l khi lng CTR trn mt n v th tch, tnh bng kg/m3. Khi lng ring ca CTRT s rt khc nhau ty theo phng php lu tr: (1) Gio trnh Qun l cht thi rn th 27 t nhin khng cha trong thng, (2) cha trong thng v khng nn, (3) cha trong thng v nn. Do, sliukhilngringcaCTRTchcngha khic ghi ch km theo phng php xc nh khi lng ring. Khi lng ring ca CTRT s rt khc nhau ty theo v tr a l, ma trong nm, thi gian lu tr, Do , khi chn gi tr khi lng ring cn phi xem xt c nhng yu t ny gim bt sai s ko theo cho cc php tnh ton. Phng php phn tch khi lng ring ca CTRT Mc d khi lng ring c nh ngha l khi lng CTR tnh trn mt n v th tch ca CTR. Tuy nhin do th tch khi CTR b nh hng rt ln bi iu kin nn p v lu tr, nn khng th p dng chung mt cch o c cho tt c cc trng hp. tnh ton thit b lu tr, thu gom, vn chuyn hay bi chn lp, phng php xc nh khi lng ring cho mi trng hp s khc nhau. V vy, trc khi tin hnh phn tch khi lng ring ca CTR cn xc nh r vic phn tch khi lng ring nhm mc ch g? Khi lng ring ca CTR cha trong cc thng cha CTR ti h gia nh c xc nh bng cch cn xc nh khi lng CTR ti a c th cha trong thng v o th tch ca thng cha. Khi lng ring c tnh bng khi lng chia cho th tch o c (tnh theo kg/m3). i vi tng thnh phn CTR ring bit, phng php xc nh khi lng ringcng cthc hinmtcchtngt.Vicxcnh khi lngringcatng thnh phn c trong CTRT l c s c tnh khi lng ring ca mt hn hp CTR btk(xemvd2.2).Vd vktquxcnh khilngringcaccthnhphn CTR t khu dn c (khng nn) do Tchobanoglous v cng s (1993) nghin cu c trnh by trong Bng 2.10. Bng 2.10 Khi lng ring ca cc thnh phn c trong CTR (khng nn) t khu dn c Loi cht thi Khi lng ring (kg/m3) Khong dao ngc trng Thc phm130 - 480290 Giy 41 - 13089 Carton41 - 8050 Nha41 - 13065 Vi41 - 10165 Cao su101 - 202130 Da101 - 261160 Rc vn 59 - 225101 G130 - 320237 Thy tinh160 - 480196 Lon thic 50 - 16089 Nhm 65 - 240160 Cc kim loi khc130 - 1.151320 Bi, tro,320 - 1.000480 Tro 650 - 830745 Rc 89 - 181130 Ngun: Tchobanoglous v cng s, 1993. xc nh khi lng ring ca CTR trong cc xe thu gom (660 L hoc xe y tay) cn phixcnhkhilngvthtchtngngcaCTRchatrongloixethugom. KhilngCTRtrongxethugomcthxcnhtitrmtrungchuynctrmcn Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 28bngcchcnkhilngxechaCTRivotrm(m1)vkhilngxekhng ira khitrm(m2).ThtchCTRtngngchatrongxethugomcthobngcch dng thc o kch thc theo ba chiu: di x rng x cao tnh (V). Da trn kt qu o c, khi lng ring ca CTR trong xe thu gom c tnh theo cng thc sau: V m m2 1 = (kg/m3 hay tn/m3) Mtcchtngt,khilngringcaCTRtrongccxevnchuynphicxc nhtheoloixe(dkin)sdng(cphockhngp),bngcchxcnhkhi lng(tia)CTRcthchatrongdungtchcaxe.KhilngCTRtrongxevn chuyn c th xc nh ti trm cn vo bi chn lp (BCL) bng cch cn khi lng xe cha CTR i vo BCL (m1) v khi lng xe khng i ra khi BCL (m2). Th tch CTR tng ng cha trong xe chnh l dung tch ca xe (thng s c tnh xe s dng, gi tr nysnc,V).Datrnktquoc,khilngringcaCTRtrongxethugom c tnh theo cng thc sau: ''2'1V m m = (kg/m3 hay tn/m3) KhilngringcaCTRtrongBCLkhcthxcnhchnhxcnhtvcclp pha y BCL, CTR c nn nhiu hn nn khi lng ring s ln hn cc lp pha trn. Thm vo , CTR cc lp di b phn hy nhiu hn cc lp trn (mi chn) nnmcbnnpcngkhcnhauvdokhilngringcngskhcnhau. Thit b s dng nn CTR ti BCL cng l yu t gy nh hng n khi lng ring ca CTR trong BCL. Tuy nhin, c gi tr tnh ton thit k, c th s dng s liu o c ti cc BCL v ang vn hnh a phng tnh khi lng ring ca CTR trongBCL.TheocchnycnxcnhtngkhilngCTRchnlp(theokhi lng cn ti trm cn ca BCL) v o th tch chn lp CTR (di x rng x chiu cao chn lp, khng k th tch chim ch ca vt liu che ph hng ngy v che ph trung gian). Khi lng ring ca CTR trong BCL s bng tng th tch CTR chn lp chia cho th tch chn lp CTR (tnh bng kg/m3 hay tn/m3). V CTR c tnh khng ng nht v thnh phn khng ging nhau gia nhng ngy khc nhau, nn xc nh khi lng ring cn tin hnh nhiu ln ly gi tr trung bnh v tt nht l c c tp s liu ln xc nh gi tr c tn sut xut hin cao nht theo xc sut thng k. Phng php c tnh khi lng ring ca mt hn hp CTR bt k Khi lng ring ca mt hn hp CTR bt k c th c c tnh da trn kt qu xc nh khi lng ring ca tng thnh phn CTR. Cch thc tnh ton c trnh by chi tit trong V d 2.2. Gio trnh Qun l cht thi rn th 29V d 2.2 c tnh khi lng ring TnhkhilngringcamuCTRcthnhphnnhtrnhbytrongBng2.11,s dng s liu khi lng ring ca tng thnh phn CTR trong Bng 2.10. Bng 2.11 Thnh phn ca mu CTR cn xc nh khi lng ring Thnh phnT l (%) Thc phm78 Giy8 Carton3 Nha4 Vi1 Cao su1 Da1 Rc vn2 G2 Tng cng100 Bi Gii Gi s khi lng ca mu CTR cn xc nh khi lng ring l 100 kg. Khi lng v th tch ca tng thnh phn cng nh ca mu CTR c trnh by trong Bng 2.12. Bng 2.12 Khi lng v th tch ca tng thnh phn cng nh ca mu CTR Thnh phnT l %Khi lng (kg)Khi lng ring (kg/m3) Th tch (m3) Thc phm78782900,269 Giy88890,090 Carton33500,060 Nha44650,062 Vi11650,015 Cao su111300,008 Da111600,006 Rc vn221010,020 G222370,008 Tng cng1001000,538 Khi lng ring ca mu CTR cn xc nh l 186538 , 0100= = =Vm(kg/m3) m mcaCTRthngcbiudintheomttronghaicch:tnhtheothnhphn phn trm khi lng t v thnh phn phn trm khi lng kh. Trong lnh vc qun l CTR, phng php khi lng t thng dng hn. Theo cch ny, m ca CTR c th biu din di dng phng trnh nh sau: 100 =wd wMChng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 30Trong : - M: m (%); - w: Khi lng ban u ca mu CTR (kg); - d: Khi lng ca mu CTR sau khi sy kh n khi lng khng i 1050C (kg). Phng php phn tch m ca CTRT mcaCTRcthphntchtrongphngthnghimbngcchsykhmu 105oC.KhiphntchmcaCTR,lngmusdngcngnhiucngtt.Khi lng mu ti thiu phi c 100 g. Trnh t phn tch m ca mu CTR nh sau: -Sy a ng mu 105oC trong 1 gi, sau lm ngui trong bnh ht m 1 gi, cn xc nh khi lng a (m0); -Cho mu CTR t vo a ( sy v cn), cn khi lng a v mu CTR trc khi sy (m1); -Sy mu nhit 105oC cho n khi t khi lng khng i. Sau mi ln sy, lm ngui mu trong bnh ht m 1 gi trc khi cn. Lp li qu trnh sy v cn mu cho n khi gi tr khi lng gia cc ln cn khng lch nhau qu 5%. Khi lng ca a v mu CTR sau khi sy l m2.- m ca mu CTR (M (%)) c tnh theo cng thc sau: 1000 12 1=m mm mM -Khi phn tch m ca mu CTR cng phi th nhiu mu ly gi tr trung bnh. Phng php c tnh m ca mt hn hp CTR bt k m ca mt hn hp CTR bt k c th c c tnh da trn kt qu xc nh m ca tng thnh phn CTR. V d v kt qu xc nh m ca cc thnh phn CTR t khudnc(khngnn)theoTchobanoglousvcngs(1993)ctrnhbytrong Bng 2.13. Cch thc tnh ton m ca hn hp CTR bt k da trn m ca tng thnh phn CTR c trnh by chi tit trong V d 2.3. Bng 2.13 m ca cc thnh phn c trong CTR (khng nn) t khu dn c Loi cht thi m (%) Khong dao ngc trng Thc phm50-8070 Giy4-106 Carton4-85 Nha1-42 Vi6-1510 Cao su1-42 Da8-1210 Rc vn30-8060 G15-4020 Thy tinh1-42 Lon thic2-43 Gio trnh Qun l cht thi rn th 31Nhm2-42 Cc kim loi khc2-43 Bi, tro6-128 Tro6-126 Rc 5-2015 Ngun: Tchobanoglous v cng s, 1993. V d 2.3 c tnh m Tnh m ca mu CTR c thnh phn nh trnh by trong Bng 2.11, bit m ca tng thnh phn CTR c gi tr nh trong Bng 2.13. Bi gii Gi s mu CTR cn xc nh m c khi lng 100 kg. Khi lng t v kh ca tng thnh phn cng nh ca mu CTR c trnh by trong Bng 2.14. Bng 2.14 Khi lng t v kh ca tng thnh phn cng nh mu CTR cn xc nh m Thnh phnT l (%) m (%) Khi lng t (kg)Khi lng kh (kg) Thc phm78707823,40 Giy8687,52 Carton3532,85 Nha4243,92 Vi11010,90 Cao su1210,98 Da11010,90 Rc vn26020,80 G22021,60 Tng cng10010042,87 m ca mu CTR cn xc nh l % 13 , 57 10010087 , 42 100= = M Kh nng tch m KhnngtchmcaCTRltnglngmmchtthicthtchtrc.yl thngscnghaquantrngtrongvicxcnhlngncrrcsinhratBCL. PhnncdvtqukhnngtchmcaCTRsthotrangoithnhncrrc. Kh nng tch m thay i ty theo iu kin nn p v trng thi phn hy ca cht thi. Kh nng tch m ca CTRT trong trng hp khng nn c th dao ng trong khong 50-60%. Tnhdnnc(hydraulicconductivity)caCTRnnlthngsvtlquantrng khng ch s vn chuyn ca nc r r v kh trong BCL. H s thm thu c th biu din theo phng trnh sau: k Cd K = =2 Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 32Trong : -K= H s thm thu; -C= Hng s v th nguyn hay h s hnh dng; -d= Kch thc l trung bnh; -= Khi lng ring ca nc; -= nht ng hc ca nc; -k= thm thu. Thng s Cd2 l thm thu thc, ch ph thuc vo tnh cht ca CTR, k c s phn b kch thc l rng, b mt v xp. Gi tr thm thu c trng i vi CTR nn trong BCL thng dao ng trong khong 10-11 n 10-12 m2 theo phng thng ng v khong 10-10 m2 theo phng ngang. Qu trnh chuyn ha l hc Nhngbinilhccbncthxyratrongqutrnhvnhnhhthngqunl CTR bao gm (1) phn loi, (2) gim th tch c hc, (3) gim kch thc c hc. Nhng bin i l hc khng lm chuyn pha (v d t pha rn sang pha kh) nh cc qu trnh bin i ha hc v sinh hc. Phnloichtthi.Phnloichtthilqutrnhtchringccthnhphnc CTRT,nhmchuynchtthitdnghntpsangdngtngingnht.Qu trnhnycnthitthuhinhngthnhphncthtisinhtitisdngctrong CTRT,tchringnhngthnhphnmangtnhnguyhivnhngthnhphnckh nng thu hi nng lng. Gim th tch c hc. Phng php nn, p thng c p dng gim th tch cht thi.Xethugomthngclptbphnpnhmtngkhilngrccththu gomtrongmtchuyn.Giy,carton,nhavlonnhm,lonthicthugomtCTRT c ng kin gim th tch cha, chi ph x l v chi ph vn chuyn. tng thi gian s dng BCL, CTR thng c nn trc khi ph t. Gimkchthcchc.Gimkchthcchtthinhmthucchtthickch thc ng nht v nh hn so vi kch thc ban u ca chng. Cn lu rng gim kchthcchtthikhngcnghalthtchchtthicngphigim.Trongmts trng hp, th tch ca cht thi sau khi gim kch thc s ln hn th tch ban u ca chng. 2.4.2 Tnh cht ha hc Cng thc phn t ca cht thi rn CcnguyntcbntrongCTRTcnphntchbaogmC(carbon),H(Hydro),O (Oxy),N(Nit),S(Luhunh)vtro.Ccnguyntthucnhmhalogencngc xc nh do cc dn xut ca clo thng tn ti trong thnh phn kh thi khi t rc. Kt qu xc nh cc nguyn t c bn ny c s dng xc nh cng thc ha hc ca thnh phn cht hu c c trong CTRT cng nh xc nh t l C/N thch hp cho qu Gio trnh Qun l cht thi rn th 33trnh lm phn compost. S liu v cc nguyn t c bn ca tng thnh phn cht thi chycctrongCTRcakhudnctheonghincuTchobanoglousvcngs (1993)ctrnhbytrongBng2.15.Ccbctnhtonxcnhcngthcphnt ca mt mu CTR bt k da s liu cc nguyn t c bn c trong tng thnh phn CTR c trnh by chi tit trong V d 2.4. Bng 2.15 Thnh phn cc nguyn t ca cc cht chy c c trong CTR t khu dn c Thnh phn Phn trm khi lng kh (%) CarbonHydroOxyNitLu hunhTro Cht hu c Cht thi thc phm48,06,437,6 2,6 0,45,0Giy43,56,044,0 0,3 0,26,0Carton44,05,944,6 0,3 0,25,0Nha60,07,222,8 - -10,0Vi55,06,631,2 4,6 0,152,5Cao su78,010,0- 2,0 -10,0Da60,08,011,6 10,0 0,410,0Rc vn47,86,038,0 3,4 0,34,5G49,56,042,7 0,2 0,11,5Cht v c Thy tinh(1) 0,50,10,4 < 0,1 -98,9Kim loi(1) 4,50,64,3 < 0,1-90,5Bi, tro,26,33,02,0 0,5 0,268,0Ngun: Tchobanoglous v cng s, 1993. (1) Nng lng c t lp ph, nhn hiu v nhng vt liu nh km V d 2.4 Xc nh cng thc phn t ca mu CTR Xc nh cng thc phn t ca mu CTR c thnh phn nh trnh by trong Bng 2.11. Bi gii Gi s mu CTR cn xc nh cng thc phn t c khi lng l 100 kg. Gi tr thnh phn phn trm, m, khi lng kh cng nh thnh phn % ca cc nguyn t c bn c trong tng thnh phn CTR c trnh by tm tt trong Bng 2.16. Bng 2.16 Thnh phn, m, khi lng kh, thnh phn % cc nguyn t c bn Thnh phn T l (%) m (%) Khi lng kh (kg) %C%H%O%N%S%tro Thc phm787023,4048,06,437,62,60,45,0 Giy867,5243,56,044,00,30,26,0 Carton352,8544,05,944,60,30,25,0 Nha423,9260,07,222,8--10,0 Vi1100,9055,06,631,24,60,152,5 Cao su120,9878,010,0-2,0-10,0 Da1100,9060,08,011,610,00,410,0 Rc vun2600,8047,86,038,03,40,34,5 G2201,6049,56,042,70,20,11,5 Tng cng10042,87 Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 34Khi lng (kh) ca cc nguyn t c bn c trong tng thnh phn cng nh ca mu CTR c tnh ton t s liu Bng 2.16 v trnh by trong Bng 2.17. Bng 2.17 Khi lng (kh) cc nguyn t c bn c trong tng thnh phn ca mu CTR Thnh phnKhi lng kh (kg) Khi lng (kg) CHONSTro Thc phm23,4011,23201,49768,79840,60840,09361,1700 Giy7,523,27120,45123,30880,02260,01500,4512 Carton2,851,25400,16821,27110,00860,00570,1425 Nha3,922,35200,28220,8938--0,3920 Vi0,900,49500,05940,28080,04140,00140,0225 Cao su0,980,76440,0980-0,0196-0,0980 Da0,900,54000,07200,10440,09000,00360,0900 Rc vun0,800,38240,04800,30400,02720,00240,0360 G1,600,79200,09600,68320,00320,00160,0240 Tng cng42,8721,08302,772615,64450,82090,12332,4262 -Cng thc phn t ca mu CTR trong trng hp c S: CxHyOzNtSu 32:14:16:1:12: : : :S N O H Cm m m m mu t z y x = 321233 , 0:148209 , 0:166445 , 15:17726 , 2:120830 , 21: : : : = u t z y x x : y : z : t : u = 1,757 : 2,773 : 0,978 : 0,059 : 0,004 = 439 : 693 :245 : 15 : 1 Vy cng thc ca mu CTR kh trong trng hp c S l C439H693O245N15S -Cng thc phn t ca mu CTR kh trong trng hp khng c S: CxHyOzNt 14:16:1:12: : :N O H Cm m m mt z y x = 148209 , 0:166445 , 15:17726 , 2:120830 , 21: : : = t z y x x : y : z : t = 1,757 : 2,773 : 0,978 : 0,059 = 30 : 47 : 17 : 1 Vy cng thc phn t ca mu CTR kh trong trng hp khng c S l C30H47 O17N - i vi mu CTR t, khi lng ca nguyn t H v O s khc trng hp mu CTR khdocsthamgiacaH2O(mtrongCTR).KhilngH2OtrongmuCTR phn tch l m(H2O) = khi lng CTR t khi lng CTR kh = 100 42,87 = 57,13 kg hay 3,17 kmol (H2O) Khi lng H v O do nc c trong CTR to nn lGio trnh Qun l cht thi rn th 35 MH(H2O) = 6,340 kg v MO(H2O) = 50,720 kg Khi lng C, H, O, N, S trong mu CTR t ln lt l + mC = 21,0830 kg+ mH = 2,7726 + 6,340 = 9,1123 kg + mO = 15,6445 + 50,720 = 66,3645 kg + mN = 0,8209 kg + mS = 0,1233 kg Bngcchtnhtngtnhtrn,cngthcphntcamuCTRttrongtrng hp c v khng c S ln lt l: C439H2278O1037N15S v C30H154O70N Nng lng cha trong cc thnh phn cht thi rn Nng lng v phn cht tr c trong cc thnh phn ca CTR t khu dn c theo nghin cucaTchobanoglousvcngs(1993)ctrnhbytrongBng2.18.Ccgitr nng lng trnh by trong Bng 2.18 c th chuyn i sang nng lng tnh trn khi lng kh theo phng trnh sau: Trongtrnghptnhtheokhilngkhvkhngkthnhphntro,phngtrnh tnh ton tng ng nh sau: Nng lng ca tng thnh phn cht thi cng c th c tnh ton mt cch gn ng theophngtrnhsau(ylphngtrnhcxydngtrncsphngtrnh Dulong) (Tchobanoglous v cng s, 1993):

Trong : -C: Carbon, % khi lng; -H2: Hydro, % khi lng; -O2: Oxy, % khi lng; -S: Lu hunh, % khi lng; -N: Nit, % khi lng; -Btu/lb x 2,326 = KJ/kg. Trong tha s (H2 - 1/8 O2) tnh cho phn hydro phn ng vi oxy, v thnh phn ny khng tham gia to nng lng ca cht thi.Nng lng KJ/kg(Tnh theo khi lng kh) Nng lng KJ/kg(Tnh theo khi lng t) = x 100 100 m (%) Nng lng KJ/kg(Theo khi lng kh, khng tro) Nng lng KJ/kg(Tnh theo khi lng t) = x 100 100 m (%) tro (%) N S O H C lb Btu + + |.|

\| + = 10 4081610 145 /2 2Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 36 Bng 2.18 Nng lng v phn cht tr c trong CTR t khu dn c Thnh Phn Phn cht tr(1) (%)Nng lng(2) (KJ/kg) Khong dao ngc trng Khong dao ngc trngCht hu c Cht thi thc phm2-85,03.489 - 6.9784.652Giy4-86,011.630 - 18.60816.747Carton3-65,013.956 - 17.44516.282Nha6-2010,027.912 - 37.21632.564Vi2-42,515.119 - 18.60817.445Cao su8-2010,0 20.934 - 27.91223.260Da8-2010,015.119 - 19.77117.445Rc vn2-64,5 2.326 - 18.6086.513G0,6-21,517.445 - 19.77118.608Cht hu c khc----Cht v c Thy tinh 96-9998,0116 - 233(3)140Lon thic 96-9998,0233 - 1163(3) 698Nhm90-9996,0--Kim loi khc94-9998,0 233 - 1163(3) 698Bi, tro,60-8070,02.326 - 11.6306978CTRT9.304 - 13.95611.630(4)Ngun: Tchobanoglous v cng s, 1993. (1)Sau khi chy hon ton (2)Theo thnh phn thu gom c (3)Nng lng c t lp ph, nhn hiu v nhng vt liu nh km (4)Gi tr nng lng trong bng ny ln hn cc gi tr tng ng trnh by Bng 4-10, ch yu do (1) lng cht thi thc phm b gim v (2) thnh phn phn trm nha gia tng (7% thay v 4%) i vi CTR ly t khu dn c. Qu trnh chuyn ha ha hc Bin i ha hc ca CTR bao hm c qu trnh chuyn pha (t pha rn sang pha lng, t pharnsangphakh,).gimthtchvthuhiccsnphm,nhngqutrnh chuyn ha ha hc ch yu s dng trong x l CTRT bao gm (1) t (qu trnh oxy ha ha hc), (2) nhit phn, v (3) kh ha. t (Oxy ha ha hc). t l phn ng ha hc gia oxy v cht hu c c trong CTR tothnhcchpchtboxyhacngvisphtsngvtanhit.Nukhngkh ccpdvdiiukinphnngltng,qutrnhtchthucctrong CTRT c th biu din theo phng trnh phn ng sau: Cht hu c+Khng kh (d) CO2 + H2O + khng kh d + NH3 + SO2 + NOx +Tro+Nhit Lng khng kh c cp d nhm m bo qu trnh chy xy ra hon ton. Sn phm cui ca qu trnh t chy CTRT bao gm kh nng cha CO2, H2O, khng kh d (O2 vN2)vphnkhngchycnli.Trongthct,ngoinhngthnhphnnycnc mtlngnhcckhNH3,SO2,NOxvcckhvilngkhctytheobnchtca cht thi. Gio trnh Qun l cht thi rn th 37Nhit phn. V hu ht cc cht hu c u khng bn nhit, chng c th b ct mch quaccphnngcrackingnhitvngngttrongiukinkhngcoxy,tothnh nhng phn kh, lng v rn. Tri vi qu trnh t l qu trnh ta nhit, qu trnh nhit phn l qu trnh thu nhit. c tnh ca 3 phn chnh to thnh t qu trnh nhit phn CTRTnhsau:(1)dngkhsinhrachaH2,CH4,CO,CO2vnhiukhkhcty thuc vo bn cht ca cht thi em nhit phn, (2) hc n v/hoc du dng lng iu kin nhit phng cha cc ha cht nh acetic acid, acetone v methanol v (3) than baogmcarbonnguynchtcngvinhngchttrkhc.Qutrnhnhitphn cellulose c th biu din bng phng trnh phn ng sau: 3(C6H10O5) 8H2O+C6H8O+2CO+2CO2+CH4+H2+7C Trong phng trnh ny, thnh phn hc n v/hoc du thu c chnh l C6H8O. Kh ha. Qu trnh kh ha bao gm qu trnh t chy mt phn nhin liu carbon to thnh kh nhin liu chy c giu CO, H2 v mt s hydrocarbon no, ch yu l CH4. Khnhinliuchycsauctchytrongngcttronghocnihi. Nu thit b kh ha c vn hnh iu kin p sut kh quyn s dng khng kh lm tc nhn oxy ha, sn phm cui ca qu trnh kh ha s l (1) kh nng lng thp cha CO2, CO, H2, CH4, v N2, (2) hc n cha C v cc cht tr sn c trong nhin liu v (3) cht lng ngng t c ging nh du pyrolic. 2.4.3 Tnh cht sinh hc ctnhsinhhcquantrngnhtcathnhphnchthucctrongCTRTlhu ht cc thnh phn ny u c kh nng chuyn ha sinh hc to thnh kh, cht rn hu c tr v cc cht v c. Mi v rui nhng sinh ra trong qu trnh thi ra cht hu c (rc thc phm). Kh nng phn hy sinh hc ca cc thnh phn cht hu c. Hm lng cht rn bay hi (VS), xc nh bng cch nung nhit 550oC, thng c s dng nh gi kh nng phn hy sinh hc ca cht hu c trong CTRT. Tuy nhin, vic s dng ch tiu VS biu din kh nng phn hy sinh hc ca phn cht hu c c trong CTRT khng chnh xc v mt s thnh phn cht hu c rt d bay hi nhng rt kh b phn hy sinh hc (v d giy in bo v nhiu loi cy king). Cng c th s dng hm lng lignin c trong cht thi xc nh t l cht hu c c kh nng phn hy sinh hc theo phng trnh sau (Tchobanoglous v cng s, 1993): BF = 0,83- 0,028 LC Trong : -BF: phn c kh nng phn hy sinh hc biu din di dng VS; -0,83: hng s thc nghim; -0,028: hng s thc nghim; -LC: hm lng lignin c trong VS tnh theo % khi lng kh. Chng 2 Ngun pht sinh, khi lng, thnh phn v tnh cht 38S hnh thnh mi. Mi sinh ra khi tn tr CTR trong thi gian di gia cc khu thu gom, trung chuyn v ra BCL, nht l nhng vng kh hu nng, do kh nng phn hykkhnhanhccchthucdbphnhyctrongCTRT.Vd,trongiu kin k kh, sulfate c th b kh thnh sulfide (S2-), sau sulfide kt hp vi hydro to thnh H2S. Qu trnh ny c th biu din theo cc phng trnh sau: 2 CH3CHOHCOOH+SO42-2 CH3COOH+S2-+H2O+CO2 LactateSulfateAcetateSulfide 4H2+SO42- S2-+4H2O S2-+2H+H2S Ion Sulfide c th kt hp vi mui kim loi sn c, v d mui st, to thnh sulfide kim loi: S2-+Fe2+FeS MuencaCTRphnhykkhBCLchyuldoshnhthnhccmui sulfidekimloi.Nukhngtothnhccmuiny,vnmicaBCLstrnn nghim trng hn. Cc hp cht hu c cha lu hunh khi b kh s to thnh nhng hp cht c mi hi nh methyl mercaptan v aminobutyric acid. CH3SCH2CH2CH(NH2)COOH CH3SH+CH3CH2CH2(NH2)COOH MethionineMethyl mercaptanAminobutyric acid Methylmercaptan c th b thy phn to thnh methyl alcohol v hydrogen sulfide: CH3SH+H2O CH4OH+H2S Cc qu trnh chuyn ha sinh hc Cc qu trnh chuyn ha sinh hc phn cht hu c c trong CTRT c th p dng gimthtchvkhilngchtthi,snxutphncompostdngbsungchtdinh dngchotvsnxutkhmethane.Nhngvisinhvtchyuthamgiaqutrnh chuyn ha sinh hc cc cht thi hu c bao gm vi khun, nm, men v antinomycetes. Ccqutrnhnycthcthchintrong iukinhiukhhockkh,tytheo lng oxy sn c. Nhng im khc bit c bn gia cc phn ng chuyn ha hiu kh v k kh l bn cht ca cc sn phm to thnh v lng oxy thc s cn phi cung cp thchinqutrnhchuynhahiukh.Nhngqutrnhsinhhcngdng chuyn ha cht hu c c trong CTRT bao gm qu trnh lm phn compst hiu kh, qu trnh phn hy k kh v qu trnh phn hy k kh vi nng cht rn cao. +2HCHNG 3 QUN L CHT THI RN TH TI NGUN 3.1 LU TR CHT THI RN TI NGUN Cc yu t quan trng cn phi xem xt i vi vic lu tr cht thi rn ti ngun bao gm (1) loi thng chasdng,(2)vtr t thng cha,(3) nh hngcaviclu trnctnh ca cht thi v (4) sc khe cng ng v m quan khu vc. 3.1.1 Loi thng cha Loi v dung tch thng cha s dng ph thuc vo c tnh v loi cht thi thu gom, loi h thng thu gom, chu k thu gom v din tch sn c t thng cha. Mt s dng thng cha cht thi ti ngun hin ang s dng Vit Nam v cc nc trn th gii c th hin trong Hnh 3.1 v Hnh 3.2. (a) Thng cha cht thi rn ti h gia nh. (b) Thng cha cht thi rn khu cng cng. Gio trnh Qun l cht thi rn th 39 (c) Thng cha cht thi rn dc ng ph. Hnh 3.1 Cc dng thng cha cht thi rn ti ngun Vit Nam.

(b)Thng cha cht thi rn cm h gia nh Wageningen H Lan. (a)Thngchachtthirnkhuktcxsinh vin Wageningen H Lan. (c) Thng cha cht thi rn khu k tc x sinh vin AIT- Bangkok Thi Lan.Chng 3 Qun l cht thi rn th ti ngun 40

(f)ThngchachtthirnkhusiuthWageningen H Lan. (g) Thng cha cht thi rn dc ng ph Paris Php.(e)Thng cha cht thi rn khun vin VinCng Ngh Chu AIT Thi Lan.(d)KhucharctptrungkhunvinVinCng Ngh Chu AIT Thi Lan.Gio trnh Qun l cht thi rn th 41 Hnh 3.2 Mt s dng thng cha cht thi rn ti ngun cc nc trn th gii. 3.1.2 V tr t thng cha rc Vtr tthngcharcphthucvo c imcangunphtsinhchtthi(nh ,trng hc, cng s, khu thng mi, x nghip,), khng gian sn c v li vo v tr thu gom. Ti hu htcctnhthnhncta,CTRctptrungtrcnhtrcthigianthugom.Cngc ni, mi khu ph, t dn ph hay chung c c mt im tp trung rc chung. Thng thng, v tr v loi thng cha cht thi ti ngun phi c la chn trn c s ph hp vi yu cu s dng ca ni pht sinh cht thi v thun tin cho cng tc thu gom. 3.1.3 nh hng ca vic lu tr n c tnh cht thi Nhng yu t quan trng cn xem xt khi lu tr cht thi rn ti ngun l nhng nh hng ca chnh vic lu tr cht thi n c tnh ca cht thi do (1) qu trnh phn hy sinh hc, (2) s hp thu cht lng v (3) s nhim bn ca cc thnh phn cht thi. Qutrnhphnhysinhhc.Chtthithcphmvnhngchtthikhctrongccthng cha ti ngun hu nh u d b phn hy sinh (thng gi l s thi ra) do s pht trin ca vi sinh vt v nm. Nu cht thi c lu tr trong thng cha trong mt khong thi gian di, rui s sinh si ny n v gy mi hi thi. V d, trong iu kin k kh, sulfate c the b kh thnhsulfide(S2-),sausulfidekthpvihydrotothnhH2S.Qutrnhnycthbiu din theo cc phng trnh sau (Tchobanoglous v cng s, 1993): 2 CH3CHOHCOOH+SO42-2 CH3COOH+S2-+H2O+CO2 LactateSulfateAcetateSulfide 4H2+SO42- S2-+4H2O S2-+2H+H2S Cchpchthucchaluhunhkhibkhstothnhnhnghpchtcmihinh methyl mercaptan v aminobutyric acid. CH3SCH2CH2CH(NH2)COOHCH3SH+CH3CH2CH2(NH2)COOH Methionine Methyl mercaptan Aminobutyric acid Methylmercaptan c th b thy phn to thnh methyl alcohol v hydrogen sulfide: (h) Thng cha cht thi rn khu nh ngh ca vn ng vin Bangkok Thi Lan. +2HChng 3 Qun l cht thi rn th ti ngun 42CH3SH+H2O CH4OH+H2S Hp thu cht lng. Do cc thnh phn ca CTR c m ban u khc nhau, qu trnh thit lp li cn bng m s xy ra khi cc cht thi ny c cha chung trong cng thng cha. Khi cha cc cht thi khc nhau trong cng thng cha, giy s hp thu nc t cht thi thc phm v rc vn m t. Mc hp thu ty thuc vo thi gian lu tr cho n khi cht thi c thugom.Nuccchtthiclutrtingunhn1tuntrongthngchakn,ms phnbuchottcccthnhphnctrongthngcha.Nukhngdngthngchakn, cht thi cng c th hp thu nc ma ri vo thng. Snhimbncaccthnhphnchtthi.Yutcbitquantrngiviviclutr cht thi ti ngun l s nhim bn cht thi. Nhng thnh phn cht thi chnh c th b nhim bn bi mt lng nh cc cht thi nguy hi nh du xe, cht ty ra v sn, do lm gim kh nng ti sinh vt liu. Trong khi s nhim bn ti ngun ny lm gim gi tr ca tng thnh phn cht thi, nhiu tranh lun cho rng iu ny cng mang li li ch khi b cc cht thi ny ra bi chn lp bi v nng ca cc cht nhim gim ng k khi cc thnh phn cht thi c phn tn v p trong qu trnh chn lp. 3.1.4 nh hng ca vic lu tr cht thi n sc khe cng ng v m quan Yutlinquannsckhecngngutinlssinhsinynccloicntrng,vi sinh vt mang mm bnh trong khu vc cha cht thi. Bin php tt nht hn ch chut b v rui l gi v sinh khu vc mt cch hp l bng cch dng thng cha c np y kn, ra thng cha cng nh lm v sinh khu vc cha cht thi theo nh k v chuyn cc cht thi c kh nng phn hy sinh hc n ni thi b theo quy nh. Vn m quan khu vc thng lin quan n s hnh thnh mi v cnh quan khng p mt do khng duy tr iu kin v sinh ph hp. Mi c th c khng ch bng cch dng thng cha kn v duy tr chu k thu gom hp l. Nu vn pht sinh mi, c th s dng cht kh mi nh mt gii php tm thi. duy tr m quan khu vc, cc thng cha phi c lau chi v ra nh k. 3.2 X L CHT THI TI NGUN Qu trnh x l cht thi c p dng (1) gim th tch, (2) thu hi vt liu c th ti s dng c,hoc(3)thayihnhdngvtlcacht thi.Cchnhthc xlcht thi tingun thng c p dng bao gm (1) phn loi cht thi, (2) p, (3) phn hu c v (4) t.

Phn loi cht thi Vic phn loi cht thi rn ti ngun l mt trong nhng phng thc hiu qu nht c th thu hi v ti s dng vt liu t cht thi rn. p p, ng kin cc loi ph liu phn loi nh carton, giy, lon, l hnh thc kh thng dng cc khu thng mi, cc nh my, x nghip, Vic s dng my p cht thi c th gim th tch ban u ca cht thi t 20-60% nhng khi lng cht thi hon ton khng thay i. Vic thu hi cht thi s khng th thc hin c tr khi cht thi ng kin c tho bung ra tr li. Nu bc x l tip theo l t, cht thi p cng phi c lm vn ra trnh lm chm qu trnh t v trnh lm tng phn vt liu khng b t chy hon ton. Tt c nhng yu t ny phi c xem xt cn thn khi quyt nh s dng my p cht thi ti ngun pht sinh. Gio trnh Qun l cht thi rn th 43 phn hu c Vonhngnm1970,chbinphnhuc(compost)ticchgianhlphngphpti chchtthihuccngdngrngri.ylphngphpgimthtchvbini thnhphnvtlcachtthimtcchhiuqungthitorasnphmphhudng. Nhiu phng php lm phn compost khc nhau c ng dng ty thuc vo khng gian sn c v cht thi dng lm phn compost. Snxutcompostsnnh.snxutcompostsnnh,ngidncnnmcmts phng php lm phn bng l cy, c v cc mu vn cy ci b ct xn. Bi cy, gc cy v g cngcthlmphncompostc.Phngphpnginnhtlvtliulmphn compost thnh ng, ti nc v o trn theo chu k cung cp m v oxy cn thit cho vi sinh vt sng v pht trin. Trong qu trnh phn compost, cc vt liu s b phn hy di tc dng ca vi sinh vt v nm cho n khi ch cn li mn (humus). Vt liu phn compost sau khi n nh sinh hc c th dng lm cht b sung dinh dng cho t hoc lm vt liu che ph. Lp ph bi c. Nhng dng lm phn compost khc nh thi c trn cc bi c mi xn. Nu cc mu c xn ny nh, chng c th ph thnh mt lp trn mt t. Theo thi gian, lp cnys cchuyn thnh phn compost. Hnh thc ny khng nhng gip lm gim lng cht thi sinh ra ti ngun m cn cho php ti sinh dinh dng. t tcht thitrongvnnhcnglmttrongnhnghnhthcxlchtthi rntingun. Tuy nhin, bin php ny ch c th p dng nhng vng nng thn, nhng khu dn c tha tht. Hin nay, cc nc, vic t cht thi sn nh b cm, nht l cc khu th. y cng chnh l nguyn nhn lm tngng k lng giy, carton, v rc vn trong thnh phn cht thi rn thu gom. CHNG 4 H THNG THU GOM 4.1HTHNGTHUGOMCHTTHIRNTCCNGUNPHTSINHC KHI LNG NH 4.1.1 Hnh thc thu gom Cc ngun pht sinh c khi lng nh bao gm h gia nh, vn phng, cng s, cc ca hng tpha,ccqunn,nhhng,khchsn,trnghc,nmtrongkhudnc,trongc trng nht l h gia nh. Cng c mt s nh hng, khch sn, trng hc c quy m ln (khi lng CTR pht sinh mi ngy ln hn khi lng cha c trong 1 xe thu gom 660 L, khong 350 kg). Tuy nhin, s lng cc ngun ny khng nhiu v thng nm ri rc trong khu dn c, nn tin cho vic t chc tuyn thu gom, cc ngun ny vn c xem l ngun pht sinh c khi lng nh. nc ta, khu dn c cha c quy hoch mt cch ng b, cc khu ph rt khc nhau gia ccquntrongcngthnhphvgiacccmdnctrongcngmtqun.Nunhcc qun trung tm thng tp trung cc ng ph ln, c phn lung giao thng r rng, cc qunkhctlnghmsnhiuhn,conthucng1chiuvconlng 2 chiu.Do,hotngthugomCTRtccngunphtsinhckhilngnhnycngs khc nhau ty theo tng a bn v c im ng giao thng ca khu vc. Mt cch tng qut, hot ng thu gom cht thi rn t cc ngun pht sinh c khi lng nh c thc hin theo hnh thc thu gom tng nh mt (door-to-door) v ht nh ny n nh kia trn cng mt tuyn, c th nh sau: -Trncctuynnggiaothngln,mtxeng,luthngmtchiuhayhaichiu, hnh thc thun tin nht l thu gom CTR mt bn l ng v ln lt t nh ny n nh kia. Cng nhn thu gom s y xe thu gom rng t ni tp trung, n h gia nh (hay cng s, qun n, nh hng, gi chung l h gia nh v y l ngun pht sinh chim t l cao nhttrongnhmngunphtsinhckhi lng nh)utinca tuynthugom,lyCTR, sau y xe sang h gia nh k tip v c nh th cho n khi xe y (khng th cha thm CTR na). Sau khi thu gom y xe, cng nhn s y xe cha y CTR n im tp kt (c th l im hn, trm p kn, trm trung chuyn, hay trm phn loi,) i, chuyn giao CTRvlyxerngthchinchuynthugomtiptheochonkhihonttcngtcthu gom ca mt ngy. Hnh thc thu gom ny c m t nh trn Hnh 4.1. -ivinhngtuynnggiaothngnhhaynghm,hnhthcthugomthuntin nht l ly rc hai nh i din v ln lt qua cc cp nh trn cng tuyn ng. mt s a phng, xe thu gom c s dng l xe ti (khng phi thng 660 L hay xe y tay). Do,xesumtvtrthuntintrnnghocchyrtchm,trongkhi,cng nhn thu gom s n trc tng h gia nh ly rc cho vo gi cn x, n khi y gi, cngnhnmichuynrclnxevnchuynlygikhngtiptcthugomrc.Cng vic c c tip tc cho n khi xe thu gom khng th cha thm rc na. Trong trng hp ny,cngnhnthnglyrchainhidintncngdichuyn.Hnhthcthu gom ny c m t nh trn Hnh 4.2. Gio trnh Qun l cht thi rn th 45 Hnh 4.1 Hnh thc thu gom CTR t cc ngun pht sinh c khi lng nh: thu gom mt bn ng. Hnh 4.2 Hnh thc thu gom CTR t cc ngun pht sinh c khi lng nh: thu gom hai bn ng. cc khu nh dn thuc vng o, ng i dc, trn trt, khng th y xe thu gom n tng nh, cng nhn thu gom cng phi mang cn x n tng h gia nh ly rc v chuyn xung xethugom.Trongtrnghpnykhngththugomtheotngtuynngnhmt trn.Cng nhnthugomsly rc theo tng cm h gia nh, t trn cao xung thp sao cho thun tin cho vic chuyn rc xung pha di. 4.1.2 Phng tin thu gom Phng tin thu gom CTR t cc ngun pht sinh c khi lng nh, vi ng ph nh hp v cchgianhbrcringl(tngnhmt,khngtptrungtimtim)nhncta, phng tin thu gom phi t cc yu cu k thut sau y: -Charcthugom,khnggyrivircvrrncrctrongqutrnhthugomvtrn ng vn chuyn v im tp kt; -Xe phi c kt cu v kch c ph hp cho vic di chuyn trn cc tuyn ng nh hp v ng c; -Nu phi dng sc ngi y, xe phi c sc cha va phi vi kh nng y xe cha y rc ca 1 hoc 2 cng nhn thu gom. Cc phng tin thu gom hin ang s dng nc ta c th k n gm thng 660 L, xe y tay, xe bagc, xe lam v xe ti (c bit thu gom x bn) (Hnh 4.3). Trm Xe im tp kt H gia nh 1 H gia nh 2 H gia nh 3 H gia nh 4 H gia nh n .. n tuyn tip theo Xe y Xe rng Cc h gia nh ny nm hai bn ca mt tuyn ng H gia nh 1 H gia nh 2 H gia nh 3H gia nh 4H gia nh n .. H gia nh m H gia nh m Trm Xeim tp kt H gia nh 1 H gia nh 2 H gia nh 3 H gia nh 4 H gia nh n H gia nh 1 .. n tuyn tip theo Xe y Xe rng Cc h gia nh ny nm cng mt bn ng Chng 4 H thng thu gom 46 Hnh 4.3 Cc phng tin thu gom CTR t cc ngun pht sinh c khi lng nh. 4.1.3 Phn tch tuyn thu gom, tnh ton trang thit b v nhn cng thu gom Phn tch tuyn thu gom thun tin cho vic tnh ton trang thit b thu gom, s vng quay xe thu gom, s nhn cng, nhnghotngchnhhonttmtchuynthugomCTR(haymttuynthugom)c phn thnh cc cng on nh sau: -y xe rng t trm xe (hay ni tp trung xe thu gom); -Ly CTR t mi h gia nh (ly rc mt bn ng) hay hai h gia nh (ly rc hai nh i din) v y xe gia hai nh k tip hay gia hai cp nh k tip cho n ht tuyn (n khi xe thu gom y);-y xe y n ni tp kt (im hn, trm p kn, trm trung chuyn, trm phn loi,); -i v chuyn giao CTR ti im tp kt; -y xe rng n v tr ly rc u tin ca tuyn tip theo. Cc hot ng ny c th quy i theo thi gian cn thit hon tt mt chuyn (hay mt tuyn thu gom), bao gm: - Thi gian ly rc l thi gian cng nhn thu gom n ly rc tt c cc h gia nh cng nh yxethgianhnynhgianhkia,tnhtkhibtulyrchgianhth nht cho n khi xe y rc. Thi gian ly rc c k hiu l Tly rc. - Thi gian vn chuyn l thi gian cng nhn thu gom y xe rng t im tp kt rc n v tr u tin ca tuyn thu gom v thi gian y xe cha y rc v tr cui cng ca tuyn thu gom n im tp kt. Thi gian vn chuyn c k hiu l Tvn chuyn.- Thi gian ti ni tp kt rc sau khi thu gom l thi gian ch v chuyn giao rc thu gom, c k hiu l Ttp kt. Xe y tay ci tinThng 660LXe bagc y Xe bagc myXe lamXe ti (ch x bn) Gio trnh Qun l cht thi rn th 47Thm vo , i vi mt ngy lm vic, cng nhn thu gom cn tn thi gian y xe rng t trm xe n v tr thu gom u tin ca tuyn thu gom th nht ca ngy lm vic (thi gian ny c k hiu l t1) cng nh thi gian y xe rng sau t im tp kt rc v li trm xe, kt thc mt ngy lm vic (thi gian ny c k hiu l t2). l cha k thi gian cng nhn cn ngh gia ca, ngh n tra. Thi gian ny c xem l thi gian khng thu gom v thng c tnhbnghstnhnthigiankhngthugomW.HsWctnhkhngqu15%thi giancamtngylmvic(8gi/ngilaong/ngyvcthlnhnivithitbthu gom). Nh vy thi gian hon tt mt chuyn (hay mt tuyn) thu gom (Tchuyn) CTR t cc ngun pht sinh c khi lng nh c th c biu din nh sau: Tchuyn = Tly rc + Tvn chuyn + Ttp kt(4-1) Thi gian ly rc. Nu hot ng ly rc c thc hin tun t t h gia nh ny n h gia nh kia (i vi ly rc mt bn ng) hay t cp h gia nh ny n cp h gia nh kia (ivilyrchaibnng),vicctnhthigianlyrcsrtthuntinvtngi chnh xc gia s liu tnh ton thit k v thc t vn hnh. Tnh ton ny s gp sai s rt ln nunhtrnthctcngnhnkhnglyrclnltthnynhkiamchlyrc nhng h gia nh c k hp ng thu gom rc (hnh thc da beo nh thc t hin nay). xc nh thi gian ly rc, cn kho st xc nh thi gian ly ti cha rc t h gia nh b vo xe thu gom (TLR-HG) v thi gian y xe gia hai h gia nh k cn (TLR-X). Gi s thi gian thc hin cc hot ng ny l nh nhau tt c cc h gia nh. Nu gi n l s h gia nh c ly rc ca mt chuyn hay mt tuyn thu gom, thi gian ly rc s c tnh nh sau: Tly rc (pht/chuyn) =n x TLR-HG +(n 1) x TLR-X(4-2) Thi gian vn chuyn. Thi gian vn chuyn l thi gian cn y xe thu gom rng t im tp kt n v tr ly rc u tin ca tuyn thu gom cng vi thi gian y xe thu gom y t v tr kt thc tuyn thu gom n im tp kt. Thi gian ny s thay i theo on ng i v vn tc y xe (hay chy xe, nu l xe my). Thng thng on ng phi y xe ca cc tuyn s rtkhcnhau,dothuntinkhitnhtonthitk,githitrngonngivvl bng nhau, c ly trung bnh v gii hn theo on ng xa nht m cng nhn thu gom c th y xe rc y v im tp kt. Nu gi on ng y xe l h, vn tc y xe rc rng l vXR v vn tc y xe rc y l vX, thi gian vn chuyn c tnh ton nh sau: hh Tvn chuyn (pht/chuyn) =----- + -----(4-3) vXR vX Nh vy, mun tnh ton thi gian vn chuyn, cn xc nh v tr im tp kt sau khi thu gom. Hay ni cch khc, mng li im hn, v tr trm trung chuyn/trm phn loi/x l phi c quyhochtrckhitnhtonthigianthchinmtchuyn(haymttuynthugom).Hnh thc v phng tin thu gom cng phi c la chn trc lm c s cho vic tnh ton s lng trang thit b cn u t v s nhn cng cn o to. Kt qu tnh ton thit k ny ch Thi gian ly ti cha rc ca tt c cc h gia nh trn tuyn thu gom Thi gian y xe qua cc h gia nh trn tuyn thu gom Thi gian y xe rng t im tp kt n v tr ly rc u tin ca tuyn thu gomThi gian y xe y t v tr ly rc cui cng ca tuyn thu gom n im tp ktChng 4 H thng thu gom 48ph hp vi mt loi trang thit b la chn. Do , nu c s thay i trang thit b, cn phi tnh ton li t u. Thi gian ti ni tp kt. Thi gian ti ni tp kt gm thi gian ch v thi gian chuyn giao rc(chuyn rc sang xe trung chuyn hoc xe vn chuyn; rc xung khu vc tp trung; xe rc vo container,). Thi gian ny thay i ty theo phng thc hot ng ca ni tip nhn rc.Thngthngthigiantnnhiunhtlthigianchidotptrungqunhiuxethu gom v mt lc hay do xe vn chuyn n mun, Do , khi thit k v vn hnh im tp kt rc sau thu gom, cn hn ch n mc thp nht thi gian xe thu gom phi ch rc. Nu thay cc gi tr trong phng trnh (4-2) v (4-3) vo phng trnh (4-1), thi gian cn thit hon tt 1 chuyn (hay 1 tuyn) thu gom CTR t cc ngun pht sinh c khi lng thp c th c biu din nh sau: hh Tchuyn = n x TLR-HG + (n 1) x TLR-X + ----- +-----+ Ttp kt (4-4) vXRvX Tnh ton thit b thu gom cn u t Vic tnh ton trang thit b thu gom cn u t c thc hin theo cc bc sau: Bc 1: Xc nh cc thng s ban u phc v tnh ton thit k Cc thng s ban u phc v vic tnh ton thit k bao gm: -Xc nh hnh thc thu gom (mt bn l ng hay hai nh i din); -La chn nhng loi thit b thu gom d kin s dng. Vi mi loi phi thc hin tt c cc bctnhtonnhtrnhbymcny.Datrnslngthitbcnut,thigians dng ( tnh khu hao), tnh ton vn u t cn cho mi loi, t so snh v chn loi thit b va p ng yu cu k thut va c li v mt kinh t. -Xc nh cc c tnh k thut ca xe bao gm: (1) Dung tch xe (m3); (2) Khi lng ring ca CTR trong xe (tn/m3) hay h s hu dng ca xe. Cch tt nht l phi xc nh c khi lng ring ca CTR trong xe thu gom. Trong trng hp khng xcnhckhilngring,cthsdnghshudngf.ivixekhngp, khng c php ch y hn ming xe, h s hu dng f = 0,80-0,95. i vi xe p, h s hu dng s ph thuc vo mc nn p, c th dao ng trong khong 1,5-2,0 ty xe. KhilngringcaCTRtrongxethugomphicxcnhtheocchthctrnh by trong Chng 2. (3) Xe c vn hnh th cng (y) hay c gii (xe my); (4) Thi gian khu hao thng (nm). -Xc nh thi gian ly rc ti mi ngun (v d h gia nh), thi gian y xe gia hai ngun (hai h gia nh k cn);

-Xc nh v tr cc im tp kt CTR sau thu gom c tnh on ng vn chuyn (h); -Xc nh vn tc y xe rng v xe cha y rc; -Xc nh tng khi lng CTR cn phi thu gom trn a bn trong mt n v thi gian; -Xc nh chu k thu gom (1 ln/ngy, 1 ln/tun,); Gio trnh Qun l cht thi rn th 49 -KhilngCTRphtsinhtmingun(vdkhilngCTRtmthgianh).Khi lngCTRtmihgianhcthxcnhdatrntcphtsinhCTRtnhbng kg/ngi.ng v s ngi/h gia nh; -Thigiancamtngylmvicquynhivicngnhnthugom(thngtnhbng8 gi/ngy). Bc 2: Tnh ton s lng thit b cn u t Tnh ton s lng thit b cn u t c tin hnh theo cc bc sau: -S h gia nh (hay s ngun) thu gom c trong mt chuyn (h/chuyn) -Thi gian hon tt mt chuyn (hay mt tuyn) thu gom hh Tchuyn = n x TLR-HG + (n 1) x TLR-X + ----- +-----+ Ttp kt

vXRvX -S chuyn thu gom ca mi xe thu gom/ngy (s vng quay xe) (chuyn/ngy) -Tng s chuyn cn thu gom ton b CTR ca khu vc trong ngy -Tng s xe thu gom cn u t Sc cha ca xe thu gom xKhi lng ring ca rc trong xe thu gom S ngi/hxTc pht sinh CTR tnh theo kg rc/ngi.ng m3/chuyn xkg/m3 Ngi/hxkg rc/ngi.ng = h/chuynThi gian thu gom/ngy Thi gian thc hin 1 chuyn thu gom Nd = 8 h/ngy thi gian khng thu gom rc Thi gian thc hin 1 chuyn thu gomNd = Tng khi lng CTR cn thu gom/ngy Khi lng CTR thu gom/chuynN = Tng khi lng CTR cn thu gom/ngy Dung tch xe x khi lng ring CTR trong xeN = Tng s chuyn cn thu gom/ngy S chuyn/xe/ngym = Chng 4 H thng thu gom 50- Tng t tnh ton tng s xe thu gom cn cho tng nm -Tnh ton s lng xe cn u t qua tng nm. Bc 3: So snh chi ph u t -Vi s lng thit b cn u t tnh ton bc 2, c tnh tng vn u t, chi ph sa cha ln v sa cha nh (nu cn); -So snh chi ph cho tng loi thit b v la chn. V d 4.1 Tnh s lng xe thu gom cn u t thu gom cht thi rn t h gia nh Tnh s lng xe thu gom cn u t thu gom CTR t cc h gia nh ca Qun A, bit rng: -Hnh thc ly rc l mt bn l ng; -S dng thng 660 L thu gom, cng nhn thu gom phi y xe; -Khi lng ring ca cht thi rn cha trong thng thu gom l 250 kg/m3 -Thi gian s dng thng l 3 nm; -Thi gian ly rc ti mt h gia nh l 0,5 pht/h; -Thi gian di chuyn gia hai h gia nh l 0,5 pht; -on ng phi y xe t im hn n ni ly rc l 3,5 km; -Vn tc y xe rng l 5 km/h v xe y l 4 km/h; -Thi gian ch v chuyn giao CTR l 6 pht/chuyn; -Tng khi lng CTR cn thu gom trn a bn Qun nm 2004 l 258 tn/ng; -Chu k thu gom l 1 ln/ngy; -Mi h gia nh trong khu vc c 5 ngi; -Tc pht sinh CTR ca mi ngi l 0,65 kg/ngi.ng; -Thi gian lm vic ca cng nhn thu gom l 8 gi/ngy; -H s tnh n thi gian khng lm vic l W = 0,05 Bi gii 1. Xc nh s h thu gom c trong mt chuyn 2. Thi gian hon tt mt chuyn (hay mt tuyn) thu gom hh Tchuyn = n x TLR-HG + (n 1) x TLR-X + ----- +-----+ Ttp kt

vXRvX 51 x 0,5 + (51 1) x 0,5 3,5 3,5 6 Tchuyn = --------------------------------- + ------ + ----- + ----- = 2,52 h/chuyn 60 5 460 3. S chuyn thu gom ca mi xe thu gom/ngy (s vng quay xe) (chuyn/ngy)Sc cha ca xe thu gom xKhi lng ring ca rc trong xe thu gom S ngi/hxTc pht sinh CTR tnh theo kg rc/ngi.ng 0,66 m3/chuynx250 kg/m35 ngi/hx0,65 kg/ngi.ng = 51 h/chuyn Gio trnh Qun l cht thi rn th 51 4. Tng s chuyn cn thu gom ton b CTR ca khu vc trong ngy 5. Tng s xe thu gom cn u t Tnhtngtchonhngnmtrongtnglai,txcnhslngxecnutchomi nm. Tnh ton nhn cng thu gom Slngnhncngthugomcnthit s thayitytheochlmvic,hnhthcqunl thit b thu gom v hot ng ca h thng thu gom: -Thi gian lm vic trong ngy (8 gi/ngy) v trong tun (40 gi/tun). -S lng thit b thu gom m mi cng nhn c qun l (1 xe thu gom/cng nhn; 2 xe thu gom/cngnhn,3xethugom/cngnhn,).Vithitbsnc,cngnhnskhngphi ch i chuyn rc ti ni tp kt nn c th thc hin nhiu chuyn thu gom hn, nh s gim c s cng nhn cn thit v ngc li. -Vi khi lng CTR cn thu gom trn mt a bn, s lng cng nhn cn hon tt cng tcnys thay i theo khongthi gian quy nh c php thu gom v chuyn CTR n ni tp kt. 4.2HTHNGTHUGOMCHTTHIRNTCCNGUNPHTSINHTP TRUNG 4.2.1 Hnh thc thu gom Cc ngun pht sinh CTR tp trung l nhng ngun c khi lng CTR ln ( ln thu gom v chuyn thng n bi chn lp bng xe vn chuyn). Nhng ngun ny thng l ch, cc nh my nm trong khu dn c, Trong trng hp ny, xe thu gom cng chnh l xe vn chuyn. T trm xe, xe vn chuyn s n ni cn thu gom, chuyn rc ln y xe v ch thng n bi Thi gian thu gom/ngy Thi gian thc hin 1 chuyn thu gom Nd = 8 h/ngy thi gian khng thu gom rc Thi gian thc hin 1 chuyn thu gomNd = 8 x (1 W)Tchuyn

=8 x (1 0,05)2,52== 3 chuyn/thng.ngyTng khi lng CTR cn thu gom/ngy Dung tch xe x khi lng ring CTR trong xeN = 258 tn/ng x 103 kg/tn 0,66 m3/chuyn x 250 kg/m3N = = 1564 chuyn/ngyTng s chuyn thu gom/ngy S chuyn/xe/ngym = 1564 chuyn/ngy 3 chuyn/xe/ngym = = 514 xe (thng 660 L)Chng 4 H thng thu gom 52chn lp hoc trm x l. Cng c trng hp, xe phi ly hai hoc ba v tr mi y xe. Tuy nhinslngvtrlyrcmxephinsrttsovitrnghpthugomCTRtcc ngun pht sinh c khi lng t. Hnh thc thu gom CTR trong trng hp ny c trnh by trong Hnh 4.4. Hnh 4.4 Hnh thc thu gom CTR t cc ngun pht sinh tp trung. 4.2.2 Phng tin thu gom Phng tin thu gom cc ngun pht sinh CTR tp trung l cc xe vn chuyn. i vi rc thc phm (hay rc hn hp), phng tin s dng l xe p rc cc loi. i vi phn rc cn li (k c x bn), phng tin vn chuyn l cc loi xe ti.

Hnh 4.5 Phng tin thu gom-vn chuyn CTR t cc ngun pht sinh tp trung hin ang s dng ti Thnh Ph H Ch Minh. 4.2.3 Phn tch tuyn thu gom, tnh ton trang thit b v nhn cng thu gom Phn tch tuyn thu gom thuntinchovictnhtontrangthitbthugom-vnchuyn,svngquayxe,snhn cng,nhnghotng