VIII - 44
Pra Rencana Pabrik Urea Formaldehyde Concentrate
Bhp =
hp 0,2902
45 0,1306
pompa =
=
η
hp
Effisiensi motor = 80
Peters Timmerhaus 4ed ; fig. 14-38 Power pompa
=
hp 1
0,3628 80
0,2902 pompa
≈ =
=
η
hp
Spesifikasi : Fungsi
: Untuk mengalirkan air dari A – 252 ke A – 260.
Tipe : Centrifugal pump
Bahan : Commercial steel
Rate volumetrik : 8,3024 gpm
Total Dynamic Head : 62,2924 ft lbflbm Effisensi motor
: 80 Power
: 1 hp Jumlah
: 1 buah
6. Pompa Bak Kation Exchanger L – 271
Fungsi = Untuk mengalirkan air dari A – 252 ke A - 272
Tipe = Centrifugal pump
VIII - 45
Pra Rencana Pabrik Urea Formaldehyde Concentrate
L - 271 A - 252
P
1
V
1
A B
P
2
V
2
A - 272 A
∆ Z
reference plane 14 ft
3 ft 7 ft
7 ft
ρ air = 62,43 lb cuft
Rate bahan = 7,5669 m
3
jam = 32,1659 gpm = 0,0742cuft dt
Asumsi aliran turbulen :
Diameter Optimum = 3.9 x qf
0,45
x ρ
0,13
Peter Timmerhaus 4ed, pers. 15 Diameter pipa optimum = 2,0012 in
Dipilih pipa 2 in, sch 40 Foust, App. C6a
OD = 2,375 in ID = 2,067 in = 0,1722 ft
A = 0,023t
2
Kecepatan aliran, V =
pipa k
volumetri rate
area
2
cuftmnt ft
x
dtmnt 60
1
=
0233 ,
4,4537
X
60 1
=
3,1858 ftdt = 0,00054 lbft dt berdasarkan sg bahan
N
Re
= µ
ρ v
D = 63725,4208 2100
asumsi turbulen benar Dipilih pipa commercial steel
VIII - 46
Pra Rencana Pabrik Urea Formaldehyde Concentrate
= 0,00014 f = 0,032
Diguakan persamaan Bernoulli : F
x gc
x 2
v gc
g Z
P
2
∑ +
∆ +
∆ +
∆ =
− α
ρ Wf
Perhitungan Friksi berdasarkan Peters Timmerhaus 4
ed
, tabel 1, hal. 484.
Taksiran panjang pipa lurus = 31 ft
Panjang ekuivalen, Le
-
4 elbow 90 ˚
= 4 x 32 x 0,1772 = 16,5353 ft
-
1 globe valve = 1 x 300 x 0,1722
= 51,6729 ft
-
1 gate valve = 1 x 7 x 0,1722
= 1,2057 ft Panjang total pipa
= 100,414 ft
Friksi yang terjadi :
1. Friksi karena gesekan bahan dalam pipa.
D Le
v f
2
2 1
× ×
× =
gc F
=
m f
2
lb lb
ft 11,76
0,1722 2,2
3 100,414
3,1858 0,032
2 =
× ×
× ×
2. Friksi karena kontraksi dari tangki ke pipa [Peters Timmerhaus 4
ed
, hal 484]
2 v
2 2
2
gc K
F ×
× ×
= α
K = 0,4, A tangki A pipa.
m f
2
lb lb
ft 0,063
2,2 3
1 2
3,1858 ,4
= ×
× ×
=
3. Friksi karena enlargement ekspansi dari pipa ke tangki. 0,1576
32,2 1
2 3,1858
2 v
2 2
2 3
= ×
× −
= ×
× ∆
= gc
F α
m f
lb lb
ft
VIII - 47
Pra Rencana Pabrik Urea Formaldehyde Concentrate
11,981 0,1576
0,063 11,764
F F
3 2
1
= +
+ =
+ +
=
∑
F F
m f
lb lb
ft
P
1
= P
hidrostatik
= ρ
g h = 62,43 x 1 x 5,455 = 340,5860 lb
f
ft
2
P
2
= 1 atm = 2116,8 lb
f
ft
2
1 atm = 14,7 x 144 lb
f
ft
2
P = P
2
– P
1
= 1776,2140 lb
f
ft
2
; ∆P
ρ = 28,4513 ft lb
f
lb
m
0,1583 32,2
1 2
3,1932 2
v
2 2
2
= ×
× −
= ×
× ∆
gc α
ft lb
f
lb
m
Z
1
= 5,455 ft Z
2
= 11,76 ft ∆Z = Z
2
- Z
1 =
11,76 – 5,455 = 10,565 ft ; ∆Z ggc = 6,3013
m f
lb lb
ft
Persamaan Bernoulli : F
x gc
x 2
v gc
g Z
P
2
∑ +
∆ +
∆ +
∆ =
− α
ρ Wf
-Wf = 28,4513 + 6,3013 + 0,1583 + 11,981 = 46,891
m f
lb lb
ft
Sg campuran Himmelblau : berdasarkan sg bahan = 1
960 3
sg gpm
flowrate p
× ×
− =
Wf h
Perry 6ed ; pers 6-11 ; hal. 6-5.
hp 0,127
3960 1
32,166 46,891
= ×
× =
Effisiensi pompa = 45
Peters Timmerhaus 4ed ; fig. 14-37 Bhp
=
0,2821hp 45
0,127 pompa
= =
η
hp
Effisiensi motor = 80
Peters Timmerhaus 4ed ; fig. 14-38
VIII - 48
Pra Rencana Pabrik Urea Formaldehyde Concentrate
Power pompa =
hp 1
0,3527 80
0,2821 pompa
≈ =
=
η
hp
Spesifikasi : Fungsi
: Untuk mengalirkan air dari A – 252 ke A – 272.
Tipe : Centrifugal pump
Bahan : Commercial steel
Rate volumetrik : 32,166 gpm
Total Dynamic Head : 46,8910 ft lbflbm Effisensi motor
: 80 Power
: 1 hp Jumlah
: 1 buah
7. Pompa Bak cooling water L – 273
