Cc cht chng oxi ha thng c s dng l men glucose oxydase catalase. Cht ny khng nh hng n cht lng sn phm. Acide asorbic cng dng nh mt cht chng oxi ha.2.4.7.3 Yu cu:- Mun m bo hiu qu tc dng nng nitrabenzoat (C6H5COONa)- Trong sn phm phi t 0,5 1g/lt. nng ny chng ko c hi cho sc khe con ngi.- Trc khi a benzoat vo s dng cn pha chng bng nc si vi nng 0,2 - 0,3 kg/lt ri lc sch.- Tuy vi nng s dng thp khng gy hi sc khe cho con ngi nhng natribenzoat li d v trong sn phm, lm gim gi tr cm quan ca sn phm.2.5 Cng ngh sn xut nc gii kht c gaz2.5.1 S quy trnh cng ngh

ngLon /chai schAcid,mu, hngNu ngLcLm nguiPha chSir miLm lnh 5-80CPhi trnLm lnh 1-30CBo ha CO2Chit rt, ghp npLm m, thi khIn dateV thngV thngThnh phmNcX lLm lnh 5-80CCO2 lngX lCO2 sch

Hnh 2.1: S quy trnh sn xut nc ngt c gaz2.5.2 X l nc:2.5.2.1 C s l thuyt ca qu trnh x l nc:2.5.2.1.1 Qu trnh x l c hc ( qu trnh lc):L qu trnh lc ph bin v t s dng ha cht, t nh hng n cht lng sn phm.a. Mc ch: lm sch, nng cao cht lng ca nc. l qu trnh trung gian chun b cho cc qu trnh tip theo ( lc trc khi lng lc cho vic nu ng sa, sinh hot v sinh,b. Nguyn tc: da vo kch thc l ca b mt lc. loi nhng phn t c kch thc ln hn kch thc l lc.Cng ty tn Quang minh s dng b lc, ct lc.Vt liu dng lm vch lc: Dng ht: ct si, than , Dng tm: tm kim loi c l, li kim loi. Dng si: si bng, si day, si tng hp, Dng vt xp: s, si thy tinh, cao su, giy, ...Tnh nng vch lc: Gi cho cc pha rn cng nhiu cng tt. Phn b u cc l xp trn b mt vch lc. Chu c tc ng ca mi trng: thm nc, p sut, nhit , ha hc, chy n, iu kin ti sinh, c im v tc dng ca mt s vt liu lm vch ngn lc: Vt liu ct, , si:Kch thc trung bnh 0,5 - 1m t trng 2.6g/cm3 . Lp vt liu s gi li lp cn l lng c kch thc ln hn kch thc ca vt liu lc m thng qua cng on lng khng loi ra c . Lp ct cn l ni bm ca vi sinh vt, va oxi ha cht hu c nn s loi i mt s vi sinh vt gy bnh trong nc. Vt liu than hot tnh:C b mt rt ln, c kh nng hp th cc phn t dng rn v dng ln hon tan trong nc trn b mt than. Nc khi qua than hot tnh s c kh mu . C 2 phng php kh mi v v mu ca than hot tnh:a nc vo sau x l vo lc trc tip qua b lc than hot tnh. Pha trn than tn nh n kch thc nh vi chc m vo b trn nc cng phn vi liu lng t 3 15mg/l hp th cc hp cht gy ra mi, v, mu cho nc ( loi i 80 90% cht bn). Vt liu bng bng, ch giy: Vt liu bng: loi i cc tp cht l lng trong nc nh bn phn, Vt liu ch ( si nilong): dng li, ng knh l nh m , loi i cc tp cht c kch thc 1 m. Ngoi ra c th loi i mt s vi khun c trong nc nh: Bacillus, Cl, Botulium,2.5.2.1.2 qu trnh x l ha hc:a. Mc tiu ca qu trnh:Lm mm nc ( kh cc loi ion Ca2+, Mg2+, n nng yu cu), kh mui ( di dng cation v anion ca cc loi mui n nng yu cu).b. Phng php x l:KhFe2+:Trongnc,sttntidngion,hatrthnglIIlthnhphncaccmuiha:Fe(HCO3)2,FeSO4.Ncclngstcaonncmi tanh,nhiucn bnmu vng lmnh hngxu ncht lng nc.V vytin hnh khnc c hmlngst cao.Cc phng php hinnay: Khst bngphng php lmthong. Khst bngphngphp ha hc. Khbng phng php khc.Ti nhmyca cng tyBIDRICO sdngphng php lm thong.Lmthong:toiukinchooxytrongkhngkhoxyhaFe2+ thnhFe3+,hpchtcaFe3+ttantrongnccgilithngquablc. Qutrnhoxyhathchin bng cch thng gi qua nc trong ccgin phunma.Lmmm nc:phthucvohmlngccionctrongncmc ccphng phpkhc nhau: Phngphpnhit:sdngivincccngtmthi.Dotrongncc gc (HCO3)ca Ca2+, Mg2+ nn un nngs to ra ktta riemlc: Phngphptraoiion:lphngphpkinhtvnginnht.S dngphbiniviccnhmysnxutncgiikht.Thnglm mmncc cngtngithp(saukhilmmm,lnglcs b,)ngthiloib cc cht c hmlng thp.Nguyntc:sdngccchtckhnngtraoiionctrongnc.Chtckhnngtraoiion(+)trongncgilcationnitvchtckhnngtraoi vi ion ( - ) gi l anionit. Anionit c dng loi b cc acid v gc acid . Cationit c dng w loi b cc ion gy nn cng .NccliquacationnitH[R]thccionNa+,K+,Mg2+,chatrongnc s c gili:2H[R] + CaCl2 Ca[R]2 + H2O2H[R] + CaCl2 Ca[R]2 + H2O

Quahaigiaiontraoicationvaniontaloitrchuhtccion kimloik cNO3 vNO2-,nhncnhncc cngrtnhvchat tp chtcnhhng n cht lngnc.Khmui- mnnc:dngphng php chng ct,ngbng,lc qua mng bnthm(mui t10-435. 10-3 mg/l ), trao i ion, in phn, ingii.u im: Thit b c cu to n gin, quy trnh d vn hnh. Khng tn km nhiu chi ph trong qua trnh x l. Cc ct cationit v anionit c th s dng trong thi gian di.2.5.2.1.3 Qu trnh x l vi sinh:Mc ch: loi cc vi sinh vt gy hi v kh trng nc.Phng php x l:a. Phng php x l nhtNguyn tc: s dng nhit tiu dit vi sinh vt.Khixl1000C,huhtccvisinhvtubtiudit.Ccsinhvtbotcn xl 1200C. Phng php nykhngmang li hiu qukinht trong cng ngh sn xut ncgii kht.b. Phngphp lc:Nguyntc:sdngkchthclmnglcnhhnkchthcvisinhvttrong nc loi chng ra.Phng phpnytn kmchi phcho trang bnn hin nayt csdng .c. Phng php ha cht:Clo:Clorua vi:Ca(OCl2)2 + H2O HClO + HClHClO, Clorua vi: c tnh cht stkhun v ph hyc hmen cavi sinh vtPhng phpnytsdngtrongphngphpsnxutncgiikhtvthng limi ctrng nhng sdng nhiu trongnc sinh hot.d. PhngphpUV:Dngtiacctmc =254nmckhnngtiu ditvisinhvtcaonht . Cc nhmys dngn thyphnplcthp phtratiacctm,n c lpthnhb,t tronghp thytinhkhnghpthtiacctm phttiacc tmvngncch nvnc .Tronghp ngcvch ngnphnphi khincchyqua hpc trnu nhmtngthi giantipxcgia vi sinhvtc trong ncvitia cctml caonht.Lpnciquan vi dyl6nm,nnglng tiu tht6000 -13000 mw cclointhyngn hinnayccng sut 30000mw/s vibn3000-4000h.uim:khngtomil,lmmttnhcht,tomilchonc,tiudithon ton vi sinhvt v bo tca chng.Nhcim:chiphcaoccancvccchtnhnbmvon ngncn tia cc tmtc dng vo visinh vt nn hiu qu khtrng thp.e. Phng php kh trng ozon:Phngphpnyrtphbin,ngdngrngritrongnhmysnxut ncgii kht.OzonO3ctnhchtoxyhamnh(tcdngmnhgp300 -600 lnso viclo) ctcdngphhybotvisinhvt.Ctcdngcaohnhnccloihacht i vi ccloisiuvitrnglvikhunconmen.Ckhnng oxyha cccht hu cgymu,mi, v, trongnc rt tt.Cc th nghimchothy:Sau 2 phtci lng dOzon 0.45ml/l th cc siu vi trng c th btiu dit.Ozonlchtcnhmutm,nhitbayhi-1120C. thatantrong ncsoviClo,hatanphthucvonhit.Trongnc,ozonphnhyrtnhanhthnhoxiphntvnguynt.Ozonckhnngoxyhanhanhcc ion Fe2+,Mn2+,S2+, NO2-nhng khng oxyhaNH4+.i vi cc hp cht hu c, ozon ckh nng oxyha trc tip cclin kt C=C .Snphmoxyhacacc qutrnhnythngl ccchtgiu oxy vgimkhi lng phn tcccht .uimcaphngphpnylthigiantcngnhanh,hiuqucaoivi vikhun,virt,tocnlngchthuctngphncc,khngtocctrihalogenmetangycnhClonhnggithnhutcao,saukhikhtrng phixl sinh hc.2.5.2.2 S x l nc

Hnh 2.2: s thit b x l ncGhi ch:1.Lc s b.2. B cha.3. Bm.4. Lc th bng vi bng.5. lc than hot tnh6a,b.Ct lc vibng.7a,b.Ct trao i Ion.8. Bn cha.9. Lc.10a,b.H thng n cc tm.11. Bn iu. 12. Ginma.2.5.2..3 Quy trnh x l nc

Lc tinh ln 1Trao i ionLc tinh ln 2X l UVNc x lLc s bLc thNcLc than

Hnh 2.3:S quy trnh x l nc

Thuytminh quytrnh:Nc:cngtyTnQuangMinhsdnghaingunncmttthycc khucng nghip VnhLc (cthp,pHnnh)vngunncngmcsu100m(nhit nnh23270C).2.5.2.3.2 Lc s b:a. Mcch:loibcctpchtckchthclnnhct,t,rc...vcctpchtgymilnhClo,H2S...Nccbmvoblcdngphunmakhst v oxyha cc chtc trong ncnhClo...Li lc c 3lp: Lp trn cng l ct,si. Lpgialthan(ngncchgialptrnvlpgiallpvilnncv than). Lp di cng l trng.Bchavtliulccao1,2m,80%thtchblvtliulc,phatrnblhthngphunmabngccngnhaclvcnghonhitncvo. Phadi b lc lb chanc lc.Nguynlhotng:NcphuntdnphunxungkhmivoxihaFe2+thnhFe3+,Fe3+ kthpvinctothnh Fe(OH)3kttabmtrn bmt vtiulc.Cctpchtnhbn,phn,ccchtgymicngcgitrnb mtlpvtliu lc. Sau ncs cchyvo bcha.2.5.2.3.3 Lc th.a. Mc ch: loi cc tpcht l lng dng keo,huyn ph.b. Cu tao:Bnlccdnghnhtr,phatrncnghpsut,bntrongc4trnh vbng inoxdil =70 cm, ng knhd = 2 cm,tng ng vi4 cyinh lc.Cylclmtngrnghnhtrccl,ngknhcylc5cm.Bnngoiqunmtlpbngdy5cm,thmtbngncvbcbnngoibngmtlpvivbucchtbngdythun.Mingythaylpbnggnmivra schvi,dythun bngnc.2.5.2.3.4 Lc tinh.a. Mc ch: loi b tp cht c kchthc> 1m c c trong vad sng ca nc.b. Cu to:Hthngxlc3bnlctinhbnginox,trnbncnghopsut.Slngvynhvtrong3bnlnltl24,30,60cy.Chiudicccynhv l51cm,cylcl50cm.ngknhtrongcynhvl3cm,ngoiral7cm,ng knh l lc l1m.c. Vsinh:mingythonglcchngmtrongdungdchH2O215%,dngnc ra sch trongv ngoing.2.5.2.3.5 Lc thana. Mc ch: loi b mu, mi ( than) cc kh t nhin trong nc, hp th cc cht tr v mt ha hc, tp cht cn st li sau khi x l th.b. Nguyn l hot ng: nc sau khi lc th c chuyn sang bn lc than. Than hot tnh l nhm vt liu cacbon c xp cao bn mt ring rt ln c th dao ng trong khong 500 1500m2/h . Cc cu t mu, mi. Qua ht than s b gi li trong cc l xp.2.5.2.3.6 Trao i ion.a. Mcch: lmmmnc v a ncv pH = 6-8ph hp cho sn xut.b. Cuto:Thitbtraoiionc2cttraoianionvcation,chiudimict l l= 2m, ng knh l d= 50 cm,bntrong lcc htnha cationitvanionitcgilinhhaimtbch.Mimtbchc12ngnhcchiudil20cm,ngknhl4,2cm.Trnmingucccrnhnhdnncvo,kchthccclcaccrnhnhhnkchthcht nhanhmgicchtnha,phadimi ng cl dnnc vo.Htcationitvanionitckchthcrtnhmuvngnht(tronghtcationitmu smhn). Nhmyc 3 h thng trao i ion.c. Nguyn lhotng:Nc c di chuyn ln lt t ct cation n ct anion.

Ticttraoication:ncitdilntipxcvihtnhacationit R[H+], cccationnhCa2+, Na+,Mg2+ ... Tcdnghahcvi catinoitv c gili ,nci ra c hm lng ionkimloi thp nhng ctnh axit.Ti cttraoianion:loi bccionOH-, Cl-... Ncra khi ct anion mm,t tp cht.2.5.2.3.7 Tit trng UV:a. Mc ch:tiudit vi sinh vt vbo tbng nh sng cc tm.b. Cuto:Lmtnghnhtrdi50cmngknhd=12cm,bntrong lngthytinhngnkhngchoncthmvobngnvtrongcnglncc tm.c. Nguynlhotng:dngncquahthngnyditcdngcatiacctmtnhsngcancctmcbcsng = 2600 2500 A0 tiuditvisinhvt v bot. nc ra th thng tiudit UV l nc sch.d. Ccyu t nh hngtimc khtrng ca n UV: Cng bc xca tia UV. S lng visinh vttrong nc v thi gianlu thit b. ccanc(tpchthucvtpchtllng),cctpcht ny phntntiatngoinntiatngoikhngixuynhtlpnc. Hiu qu khtrng cao hnkhi ncc c thp . ylldohthngxlnctittrngUVtcuicngsauccqu trnh lc v traoi ion.e. Tin hnh: Nccbmtbchalnltquabnlcthloibtpchtc kch thc>1m ,quabnlc tinhloibtpcht nhhn. Tip ncquact cationcahthngtraoiionloiccionkimloi,qua ctanionloiccionmnhCl-, SO42- Nctiptcquabn100ml,tiyncclymukimtra,nut yucuthchuyntipquabnlctinhlnhaigilicchtckch thcrtnh(