LEMBAR PERHITUNGAN

Nama AlatTangki DegummingKode

FungsiTempat terjadinya proses degummingM-101

Tangki degumming dirancang berbentuk silinder tegak dengan head dan bottom torispherical.Data Perhitungan

Tekanan operasi, Poperasi: 1 atm

= 14,7 psi

Temperatur, T

: 110o C = 230o F

Laju alir massa, F

: 25089,72011 kg/jamDensitas campuran,

: 883,6 kg/m3= 55.16 lb/ft3Viskositas campuran, : 3,528569 cP= 0,002371234 lb/ft.s

Waktu tinggal, t

: 10 menit= 1/6 jam (EP0269277B1)Perhitungan Dimensi Silinder

Volume cairan, VL =

= 39,69 bblFaktor keamanan 10% Volume silinder, Vs= (100 + 10)% VL

= 1,1 = 183,8386 ft3 = 43,66 bblUntuk tekanan 14,7 psi, perbandingan H/D = 3 (Walas, 1990) HalVolume silinder, VS= (Brownell and Young, 1959) Pers, 3.1 Hal 41Inside diameter, ID=

Inside diameter, ID=4,273 ft = 1.2192 m = 51,276 inTinggi tangki, H = 3D = 3 4,273 ft = 12,819 ft = 3.90723 m =153,828 inPerhitungan tebal ShellBahan konstruksi

: SA-283 Grade C Tegangan maksimal yang diizinkan : 12650 psi/in2Tipe Joint

: Double-welded butt joint

Efisiensi Joint, E

: 80%Faktor korosi, C

: 0,125 in

Perhitungan tekanan

Tinggi Cairan, ft Tekanan Hidrostatik, Phidrostatik=

11,654 ft

= 642,835 lbf/ft2

= 4,46 psi

Tekanan total, Ptotal = Phidrostatik + Poperasi = 4,46 psi + 14,7 psi = 19,16 psi

Faktor keamanan, 10%

Tekanan desain, Pdesign= (100 + 10)% Ptotal

= 1,1 19,16 psi = 21,076 psiTebal shell, ts

=

= 0,1785 in

Dipakai tebal standar 3/16 in (Brownell and Young,1959)

\Perhitungan Head

Tebal head torispherical, th

=

= 0,1268 in

Dipakai tebal standar 3/16 in (Brownell and Young,1959)

Outside diameter, OD = ID + 2ts = 51,276 in + 2(3/16) in = 51,651 inDari tabel 5.7 Brownell and young (1959), diperoleh :r = 54 in

icr=3 in

Dari tabel 5.6 Brownell and young (1959), diperoleh Standard Straight Flange (sf) = 1 in

a= ID/2 = 51,276 in /2 = 25,638 in

AB= a icr = (25,638 3 ) in= 22,388 inBC= r icr = (54 - 3 ) in = 50,75 inAC=

45,545 inb= r AC = 54 45,545 = 8,455 inTinggi head, OA = th + b + sf = (3/16 + 8,455 + 1 ) in = 10,1425 in

Gambar D.1 Sketsa Head Torispherical (Brownell and Young, 1959)

Tinggi bottom, karena bottom torisherical, maka perhitunganya sama dengan head

Tinggi total tangki = tinggi silinder + tinggi head + tinggi bottom

= tinggi silinder + 2tinggi head

= 153,828 in + 2 10,1425 in

= 174,113 inPerhitungan PengadukJenis pengaduk

: Vertikal Blade Turbine ImpellerKecepatan pengaduk, v: 60 rpm = 1 rpsUntuk viskositas