Kajian Gravity Thickener sebagai Alat Pemisah Lumpur Keluaran Fermentor pada Pembuatan Biogas dari Fermentasi Limbah Cair Pabrik Kelapa Sawit Skala Pilot.
LAMPIRAN A
DATA HASIL PERCOBAAN
A.1 Perbandingan Total Solid dan Volatil Solid pada Rasio Recycle Sludge
Tabel A.1.1 Kandungan Total Solid dan Volatil Solid pada Rasio Recycle Sludge 25%
Stabil
data
(hari)
2
5
7
21
23
26
28
30
33
35
37
38
TS (mgr/L)
LCPKS
Digester
(Feed)
27.892 22.199
28.609 21.484
31.489 24.023
34.381 21.393
30.903 21.656
29.475 22.015
28.488 21.354
26.917 21.576
21.136 21.471
21.225 19.583
26.619 19.994
31.866 19.106
VS (mgr/L)
Gravity
Thickener
45.032
58.725
51.526
44.834
46.067
48.849
66.285
54.192
60.623
49.414
42.779
48.895
LCPKS
(Feed)
23.619
24.002
27.632
29.837
26.694
24.518
23.867
22.132
17.941
18.626
25.363
27.946
Digester
15.945
14.636
16.748
15.109
14.556
15.480
15.086
13.887
13.440
13.034
13.435
13.301
Gravity
Thickener
32.503
41.285
36.889
32.166
32.407
36.005
48.395
37.628
43.184
34.604
29.825
34.766
40
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Tabel A.1.2 Kandungan Total Solid dan Volatil Solid pada Rasio Recycle Sludge 34%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
LCPKS
Digester
(Feed)
44.596 27.626
42.786 28.643
56.752 26.164
40.556 26.672
40.070 25.955
31.124 23.580
34.588 23.064
32.423 23.646
36.215 25.256
38.769 24.432
37.139 26.869
40.979 24.882
Gravity
Thickener
50.175
46.710
46.894
46.221
48.539
49.916
55.405
48.535
51.103
43.831
58.619
43.580
VS (mgr/L)
LCPKS
(Feed)
37.693
36.009
40.911
33.352
31.991
25.692
28.941
26.654
30.831
33.709
30.991
34.897
Digester
18.070
18.629
17.423
16.919
14.075
15.743
15.110
15.588
17.226
16.242
18.309
16.517
Gravity
Thickener
33.821
31.185
31.924
31.228
32.052
35.433
36.937
33.941
36.159
31.229
42.245
30.478
Tabel A.1.3 Kandungan Total Solid dan Volatil Solid pada Rasio Recycle Sludge 50%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
Gravity
LCPKS
Digester
Thickener
(Feed)
33.482 14.414
38.765
37.369 14.001
32.056
33.156 14.866
49.294
31.718 16.945
43.873
30.174 14.031
47.018
36.194 16.175
51.897
31.528 16.677
49.228
27.108 18.137
50.784
38.318 18.875
47.688
33.345 18.781
35.456
32.563 15.552
46.367
34.420 12.710
60.140
VS (mgr/L)
LCPKS
(Feed)
27.270
30.742
25.942
23.999
24.212
25.989
21.431
21.366
32.563
23.219
25.729
25.420
Digester
8.745
8.611
8.485
8.753
7.754
8.630
10.489
10.851
11.317
12.530
11.611
10.626
Gravity
Thickener
24.568
21.808
35.356
28.712
33.736
35.451
34.369
35.435
34.122
28.324
32.430
45.305
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A.2 Kandungan Total Solid dan Volatil Solid pada Diameter Gravity Thickener
Tabel A.2.1 Kandungan Total Solid dan Volatil Solid pada diameter 350 mm
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
LCPKS
Digester
(Feed)
44.596 27.626
42.786 28.643
56.752 26.164
40.556 26.672
40.070 25.955
31.124 23.580
34.588 23.064
32.423 23.646
36.215 25.256
38.769 24.432
37.139 26.869
40.979 24.882
Gravity
Thickener
50.175
46.710
46.894
46.221
48.539
49.916
55.405
48.535
51.103
43.831
58.619
43.580
VS (mgr/L)
LCPKS
(Feed)
37.693
36.009
40.911
33.352
31.991
25.692
28.941
26.654
30.831
33.709
30.991
34.897
Digester
18.070
18.629
17.423
16.919
14.075
15.743
15.110
15.588
17.226
16.242
18.309
16.517
Gravity
Thickener
33.821
31.185
31.924
31.228
32.052
35.433
36.937
33.941
36.159
31.229
42.245
30.478
Tabel A.2.2 Kandungan Total Solid dan Volatil Solid pada Diameter 315 mm
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
LCPKS
Digester
(Feed)
33.482 14.414
37.369 14.001
33.156 14.866
31.718 16.945
30.174 14.031
36.194 16.175
31.528 16.677
27.108 18.137
38.318 18.875
33.345 18.781
32.563 15.552
34.420 12.710
Gravity
Thickener
38.765
32.056
49.294
43.873
47.018
51.897
49.228
50.784
47.688
35.456
46.367
60.140
VS (mgr/L)
LCPKS
(Feed)
27.270
30.742
25.942
23.999
24.212
25.989
21.431
21.366
32.563
23.219
25.729
25.420
Digester
8.745
8.611
8.485
8.753
7.754
8.630
10.489
10.851
11.317
12.530
11.611
10.626
Gravity
Thickener
24.568
21.808
35.356
28.712
33.736
35.451
34.369
35.435
34.122
28.324
32.430
45.305
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A.3 Kandungan Total Solid dan Volatil Solid pada Sludge Level
A.3.1. Gravity Thickener Tanpa Menggunakan Anulus
Tabel A.3.1 Kandungan Total Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
24
27
LCPKS
(Feed)
33,4822
37,3686
33,1558
31,7181
30,1740
36,1935
31,5281
27,1080
38,3179
33,3445
32,5634
34,4196
Digester
14,4136
14,0009
14,8663
16,9449
14,0308
16,1755
16,6769
18,1375
18,8747
18,7811
15,5521
12,7100
TS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm
11.616 10.958
9.833
9.485
11.755 11.109
11.203
9.914
12.388 12.118
13.448
12.379
13.651 13.427
13.574
14.095
13.222 12.468
13.592
13.814
11.676 10.838
10.766
10.292
10.371 10.382
10.181
9.063
10.677 10.588
10.804
9.588
10.807 11.631
10.892
11.014
11.843 13.056
12.932
13.691
14.144 13.658
14.384
11.966
10.621 12.010
13.574
13.639
130 cm
7.176
10.486
12.392
13.694
13.819
10.821
10.651
10.670
12.772
14.443
14.597
14.045
Tabel A.3.2 Kandungan Volatil Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
24
27
LCPKS
(Feed)
33,4822
37,3686
33,1558
31,7181
30,1740
36,1935
31,5281
27,1080
38,3179
33,3445
32,5634
34,4196
Digester
14,4136
14,0009
14,8663
16,9449
14,0308
16,1755
16,6769
18,1375
18,8747
18,7811
15,5521
12,7100
VS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm
11.616 10.958
9.833
9.485
11.755 11.109
11.203
9.914
12.388 12.118
13.448
12.379
13.651 13.427
13.574
14.095
13.222 12.468
13.592
13.814
11.676 10.838
10.766
10.292
10.371 10.382
10.181
9.063
10.677 10.588
10.804
9.588
10.807 11.631
10.892
11.014
11.843 13.056
12.932
13.691
14.144 13.658
14.384
11.966
10.621 12.010
13.574
13.639
130 cm
7.176
10.486
12.392
13.694
13.819
10.821
10.651
10.670
12.772
14.443
14.597
14.045
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A.3.3. Gravity Thickener Menggunakan Anulus
Tabel A.3.3 Kandungan Total Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
LCPKS
(Feed)
34.699
21.571
31.843
40.047
35.450
32.438
33.490
36.574
31.823
Digester
13.958
12.390
21.741
26.167
25.689
26.140
28.044
26.466
26.879
TS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm 130 cm
17.938 18.963
18.900 21.640 21.624
15.255 18.375
17.047 23.294 22.542
19.251 18.744
17.738 20.599 20.812
17.739 24.590
24.671 25.815 26.051
18.782 19.482
23.703 24.644 24.570
21.545 24.266
23.924 23.488 27.169
18.243 18.422
21.397 21.591 23.286
20.343 20.108
23.762 26.039 28.143
19.880 23.262
20.592 21.563 23.329
Tabel A.3.4 Kandungan Volatil Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
LCPKS
(Feed)
29.936
16.749
16.065
33.067
30.573
28.239
29.296
30.283
30.827
Digester
10.458
8.477
6.065
20.513
20.449
20.100
21.534
17.845
23.171
VS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm 130 cm
12.963 11.125
10.375 11.206 16.057
10.266 10.424
12.657 12.179 15.660
12.773 10.250
10.791 12.109 16.938
13.896 14.239
14.968 13.852 17.447
11.569 12.161
13.568 14.168 16.927
15.913 14.225
15.413 12.406 18.691
14.807 15.218
13.066 15.066 18.051
11.006 11.049
12.669 16.986 18.618
10.115 12.399
10.495 11.933 17.277
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A.4 Laju Dekomposisi Volatil Solid (VS)
Tabel A.4.1 Laju Dekomposisi Volatil Solid (VS) pada Rasio Recycle Sludge 25%
Stabil
data
(hari)
2
5
7
21
23
26
28
30
33
35
37
38
VS (mgr/L)
LCPKS
(Feed)
23.619
24.002
27.632
29.837
26.694
24.518
23.867
22.132
17.941
18.626
25.363
27.946
Digester
Discharge
15.945
14.636
16.748
15.109
14.556
15.480
15.086
13.887
13.440
13.034
13.435
13.301
11.124
8.999
9.949
10.001
8.971
9.118
7.961
8.226
7.163
6.574
7.453
7.838
VS
VS
Decomposition Decomposition
(%)
Discharge (%)
32,5%
52,9%
39,0%
62,5%
39,4%
64,0%
49,4%
66,5%
45,5%
66,4%
36,9%
62,8%
36,8%
66,6%
37,3%
62,8%
25,1%
60,1%
30,0%
64,7%
47,0%
70,6%
52,4%
72,0%
Tabel A.4.2 Laju Dekomposisi Volatil Solid (VS) pada Rasio Recycle Sludge 34%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
VS (mgr/L)
LCPKS
(Feed)
37.693
36.009
40.911
33.352
31.991
25.692
28.941
26.654
30.831
33.709
30.991
34.897
Digester
Discharge
18.070
18.629
17.423
16.919
14.075
15.743
15.110
15.588
17.226
16.242
18.309
16.517
10.774
12.362
11.161
10.264
8.009
8.954
8.553
8.151
8.361
9.767
11.236
9.035
VS
VS
Decomposition Decomposition
(%)
Discharge (%)
52,1%
71,4%
48,3%
65,7%
57,4%
72,7%
49,3%
69,2%
56,0%
75,0%
38,7%
65,1%
47,8%
70,4%
41,5%
69,4%
44,1%
72,9%
51,8%
71,0%
40,9%
63,7%
52,7%
74,1%
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Tabel A.4.3 Laju Dekomposisi Volatil Solid (VS) pada Rasio Recycle Sludge 50%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
VS (mgr/L)
LCPKS
(Feed)
33.482
37.369
33.156
31.718
30.174
36.194
31.528
27.108
38.318
33.345
32.563
34.420
Digester
Discharge
14.414
14.001
14.866
16.945
14.031
16.175
16.677
18.137
18.875
18.781
15.552
12.710
5.937
9.610
12.223
11.391
8.905
7.282
7.609
8.993
18.132
10.051
8.111
10.644
VS
VS
Decomposition Decomposition
(%)
Discharge (%)
57,0%
82,3%
62,5%
74,3%
55,2%
63,1%
46,6%
64,1%
53,5%
70,5%
55,3%
79,9%
47,1%
75,9%
33,1%
66,8%
50,7%
52,7%
43,7%
69,9%
52,2%
75,1%
63,1%
69,1%
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LAMPIRAN B
CONTOH PERHITUNGAN
B.1
Perhitungan Produksi Biogas /VS
Dari Tabel A.1.1 diperoleh:
Hari ke-1
B.2
Produksi Biogas
=
7,61 L/hari
VS LCPKS
=
26.474 mg/L
VS Discharge
=
7.616 mg/L
VS Terdegradasi
=
26.474 – 7.616 = 18.858 mg/L
Produksi Biogas/VS
7,61
0,000404 L/mgVS.hari
18858
Perhitungan Laju dekomposisi VS
Laju dekomposisi VS dapat dihitung dengan rumus di bawah ini,
Laju dekomposisi VS
=
VS POME VS DISHARGE
100%
VS POME
Pada sampel dengan rasio recycle sludge 25%
Hari ke-2 :
Dari Tabel A.4 diperoleh :
VS POME
=
23.619 mg/L
VS discharge
=
11.124 mg/L
Laju dekomposisi VS
=
23.619 11.124
100% 52,9%
23.619
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B.3
Perhitungan Bilangan Reynold
Bilangan Reynold Akibat Pengadukan
Kecepatan putaran (N)
= 37,5 rpm = 0,625 rps
Diameter Pengaduk tipe gate paddle (Da)
= 30 cm = 0,9842 ft
Densitas sludge (ρ)
= 0,9875 gram/ml = 61,6164 lb/ft3
Viscositas sludge (µ)
= 0,0053 lb/ft.s
Sehingga Bilangan Reynold
=
=
,
,
,
,
= 7.038,29
Brodley, 1998 menyebutkan bahwa pola aliran akibat pengadukan terdapat 3
(tiga) jenis yaitu laminar (Re = 10), transient (10 < Re < 104) dan turbulen (Re =
104), sehingga proses sedimentasi pada gravity thickener dengan pengadukan
37,5 rpm menghasilkan aliran transient (Re = 7.038,29).
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LAMPIRAN C
DOKUMENTASI
Gambar C.1 Rangkaian Peralatan pada Pembangkit Listrik Tenaga Biogas
(PLTBg)
Gambar C.2 Gravity Thickener yang Digunakan dalam Penelitian ini
49
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DATA HASIL PERCOBAAN
A.1 Perbandingan Total Solid dan Volatil Solid pada Rasio Recycle Sludge
Tabel A.1.1 Kandungan Total Solid dan Volatil Solid pada Rasio Recycle Sludge 25%
Stabil
data
(hari)
2
5
7
21
23
26
28
30
33
35
37
38
TS (mgr/L)
LCPKS
Digester
(Feed)
27.892 22.199
28.609 21.484
31.489 24.023
34.381 21.393
30.903 21.656
29.475 22.015
28.488 21.354
26.917 21.576
21.136 21.471
21.225 19.583
26.619 19.994
31.866 19.106
VS (mgr/L)
Gravity
Thickener
45.032
58.725
51.526
44.834
46.067
48.849
66.285
54.192
60.623
49.414
42.779
48.895
LCPKS
(Feed)
23.619
24.002
27.632
29.837
26.694
24.518
23.867
22.132
17.941
18.626
25.363
27.946
Digester
15.945
14.636
16.748
15.109
14.556
15.480
15.086
13.887
13.440
13.034
13.435
13.301
Gravity
Thickener
32.503
41.285
36.889
32.166
32.407
36.005
48.395
37.628
43.184
34.604
29.825
34.766
40
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Tabel A.1.2 Kandungan Total Solid dan Volatil Solid pada Rasio Recycle Sludge 34%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
LCPKS
Digester
(Feed)
44.596 27.626
42.786 28.643
56.752 26.164
40.556 26.672
40.070 25.955
31.124 23.580
34.588 23.064
32.423 23.646
36.215 25.256
38.769 24.432
37.139 26.869
40.979 24.882
Gravity
Thickener
50.175
46.710
46.894
46.221
48.539
49.916
55.405
48.535
51.103
43.831
58.619
43.580
VS (mgr/L)
LCPKS
(Feed)
37.693
36.009
40.911
33.352
31.991
25.692
28.941
26.654
30.831
33.709
30.991
34.897
Digester
18.070
18.629
17.423
16.919
14.075
15.743
15.110
15.588
17.226
16.242
18.309
16.517
Gravity
Thickener
33.821
31.185
31.924
31.228
32.052
35.433
36.937
33.941
36.159
31.229
42.245
30.478
Tabel A.1.3 Kandungan Total Solid dan Volatil Solid pada Rasio Recycle Sludge 50%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
Gravity
LCPKS
Digester
Thickener
(Feed)
33.482 14.414
38.765
37.369 14.001
32.056
33.156 14.866
49.294
31.718 16.945
43.873
30.174 14.031
47.018
36.194 16.175
51.897
31.528 16.677
49.228
27.108 18.137
50.784
38.318 18.875
47.688
33.345 18.781
35.456
32.563 15.552
46.367
34.420 12.710
60.140
VS (mgr/L)
LCPKS
(Feed)
27.270
30.742
25.942
23.999
24.212
25.989
21.431
21.366
32.563
23.219
25.729
25.420
Digester
8.745
8.611
8.485
8.753
7.754
8.630
10.489
10.851
11.317
12.530
11.611
10.626
Gravity
Thickener
24.568
21.808
35.356
28.712
33.736
35.451
34.369
35.435
34.122
28.324
32.430
45.305
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A.2 Kandungan Total Solid dan Volatil Solid pada Diameter Gravity Thickener
Tabel A.2.1 Kandungan Total Solid dan Volatil Solid pada diameter 350 mm
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
LCPKS
Digester
(Feed)
44.596 27.626
42.786 28.643
56.752 26.164
40.556 26.672
40.070 25.955
31.124 23.580
34.588 23.064
32.423 23.646
36.215 25.256
38.769 24.432
37.139 26.869
40.979 24.882
Gravity
Thickener
50.175
46.710
46.894
46.221
48.539
49.916
55.405
48.535
51.103
43.831
58.619
43.580
VS (mgr/L)
LCPKS
(Feed)
37.693
36.009
40.911
33.352
31.991
25.692
28.941
26.654
30.831
33.709
30.991
34.897
Digester
18.070
18.629
17.423
16.919
14.075
15.743
15.110
15.588
17.226
16.242
18.309
16.517
Gravity
Thickener
33.821
31.185
31.924
31.228
32.052
35.433
36.937
33.941
36.159
31.229
42.245
30.478
Tabel A.2.2 Kandungan Total Solid dan Volatil Solid pada Diameter 315 mm
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
TS (mgr/L)
LCPKS
Digester
(Feed)
33.482 14.414
37.369 14.001
33.156 14.866
31.718 16.945
30.174 14.031
36.194 16.175
31.528 16.677
27.108 18.137
38.318 18.875
33.345 18.781
32.563 15.552
34.420 12.710
Gravity
Thickener
38.765
32.056
49.294
43.873
47.018
51.897
49.228
50.784
47.688
35.456
46.367
60.140
VS (mgr/L)
LCPKS
(Feed)
27.270
30.742
25.942
23.999
24.212
25.989
21.431
21.366
32.563
23.219
25.729
25.420
Digester
8.745
8.611
8.485
8.753
7.754
8.630
10.489
10.851
11.317
12.530
11.611
10.626
Gravity
Thickener
24.568
21.808
35.356
28.712
33.736
35.451
34.369
35.435
34.122
28.324
32.430
45.305
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A.3 Kandungan Total Solid dan Volatil Solid pada Sludge Level
A.3.1. Gravity Thickener Tanpa Menggunakan Anulus
Tabel A.3.1 Kandungan Total Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
24
27
LCPKS
(Feed)
33,4822
37,3686
33,1558
31,7181
30,1740
36,1935
31,5281
27,1080
38,3179
33,3445
32,5634
34,4196
Digester
14,4136
14,0009
14,8663
16,9449
14,0308
16,1755
16,6769
18,1375
18,8747
18,7811
15,5521
12,7100
TS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm
11.616 10.958
9.833
9.485
11.755 11.109
11.203
9.914
12.388 12.118
13.448
12.379
13.651 13.427
13.574
14.095
13.222 12.468
13.592
13.814
11.676 10.838
10.766
10.292
10.371 10.382
10.181
9.063
10.677 10.588
10.804
9.588
10.807 11.631
10.892
11.014
11.843 13.056
12.932
13.691
14.144 13.658
14.384
11.966
10.621 12.010
13.574
13.639
130 cm
7.176
10.486
12.392
13.694
13.819
10.821
10.651
10.670
12.772
14.443
14.597
14.045
Tabel A.3.2 Kandungan Volatil Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
24
27
LCPKS
(Feed)
33,4822
37,3686
33,1558
31,7181
30,1740
36,1935
31,5281
27,1080
38,3179
33,3445
32,5634
34,4196
Digester
14,4136
14,0009
14,8663
16,9449
14,0308
16,1755
16,6769
18,1375
18,8747
18,7811
15,5521
12,7100
VS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm
11.616 10.958
9.833
9.485
11.755 11.109
11.203
9.914
12.388 12.118
13.448
12.379
13.651 13.427
13.574
14.095
13.222 12.468
13.592
13.814
11.676 10.838
10.766
10.292
10.371 10.382
10.181
9.063
10.677 10.588
10.804
9.588
10.807 11.631
10.892
11.014
11.843 13.056
12.932
13.691
14.144 13.658
14.384
11.966
10.621 12.010
13.574
13.639
130 cm
7.176
10.486
12.392
13.694
13.819
10.821
10.651
10.670
12.772
14.443
14.597
14.045
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A.3.3. Gravity Thickener Menggunakan Anulus
Tabel A.3.3 Kandungan Total Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
LCPKS
(Feed)
34.699
21.571
31.843
40.047
35.450
32.438
33.490
36.574
31.823
Digester
13.958
12.390
21.741
26.167
25.689
26.140
28.044
26.466
26.879
TS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm 130 cm
17.938 18.963
18.900 21.640 21.624
15.255 18.375
17.047 23.294 22.542
19.251 18.744
17.738 20.599 20.812
17.739 24.590
24.671 25.815 26.051
18.782 19.482
23.703 24.644 24.570
21.545 24.266
23.924 23.488 27.169
18.243 18.422
21.397 21.591 23.286
20.343 20.108
23.762 26.039 28.143
19.880 23.262
20.592 21.563 23.329
Tabel A.3.4 Kandungan Volatil Solid Sludge Level
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
LCPKS
(Feed)
29.936
16.749
16.065
33.067
30.573
28.239
29.296
30.283
30.827
Digester
10.458
8.477
6.065
20.513
20.449
20.100
21.534
17.845
23.171
VS (mgr/L)
Sludge level from bottom
210 cm 190 cm 170 cm 150 cm 130 cm
12.963 11.125
10.375 11.206 16.057
10.266 10.424
12.657 12.179 15.660
12.773 10.250
10.791 12.109 16.938
13.896 14.239
14.968 13.852 17.447
11.569 12.161
13.568 14.168 16.927
15.913 14.225
15.413 12.406 18.691
14.807 15.218
13.066 15.066 18.051
11.006 11.049
12.669 16.986 18.618
10.115 12.399
10.495 11.933 17.277
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A.4 Laju Dekomposisi Volatil Solid (VS)
Tabel A.4.1 Laju Dekomposisi Volatil Solid (VS) pada Rasio Recycle Sludge 25%
Stabil
data
(hari)
2
5
7
21
23
26
28
30
33
35
37
38
VS (mgr/L)
LCPKS
(Feed)
23.619
24.002
27.632
29.837
26.694
24.518
23.867
22.132
17.941
18.626
25.363
27.946
Digester
Discharge
15.945
14.636
16.748
15.109
14.556
15.480
15.086
13.887
13.440
13.034
13.435
13.301
11.124
8.999
9.949
10.001
8.971
9.118
7.961
8.226
7.163
6.574
7.453
7.838
VS
VS
Decomposition Decomposition
(%)
Discharge (%)
32,5%
52,9%
39,0%
62,5%
39,4%
64,0%
49,4%
66,5%
45,5%
66,4%
36,9%
62,8%
36,8%
66,6%
37,3%
62,8%
25,1%
60,1%
30,0%
64,7%
47,0%
70,6%
52,4%
72,0%
Tabel A.4.2 Laju Dekomposisi Volatil Solid (VS) pada Rasio Recycle Sludge 34%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
VS (mgr/L)
LCPKS
(Feed)
37.693
36.009
40.911
33.352
31.991
25.692
28.941
26.654
30.831
33.709
30.991
34.897
Digester
Discharge
18.070
18.629
17.423
16.919
14.075
15.743
15.110
15.588
17.226
16.242
18.309
16.517
10.774
12.362
11.161
10.264
8.009
8.954
8.553
8.151
8.361
9.767
11.236
9.035
VS
VS
Decomposition Decomposition
(%)
Discharge (%)
52,1%
71,4%
48,3%
65,7%
57,4%
72,7%
49,3%
69,2%
56,0%
75,0%
38,7%
65,1%
47,8%
70,4%
41,5%
69,4%
44,1%
72,9%
51,8%
71,0%
40,9%
63,7%
52,7%
74,1%
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Tabel A.4.3 Laju Dekomposisi Volatil Solid (VS) pada Rasio Recycle Sludge 50%
Stabil
data
(hari)
1
4
6
8
11
13
15
18
20
22
25
27
VS (mgr/L)
LCPKS
(Feed)
33.482
37.369
33.156
31.718
30.174
36.194
31.528
27.108
38.318
33.345
32.563
34.420
Digester
Discharge
14.414
14.001
14.866
16.945
14.031
16.175
16.677
18.137
18.875
18.781
15.552
12.710
5.937
9.610
12.223
11.391
8.905
7.282
7.609
8.993
18.132
10.051
8.111
10.644
VS
VS
Decomposition Decomposition
(%)
Discharge (%)
57,0%
82,3%
62,5%
74,3%
55,2%
63,1%
46,6%
64,1%
53,5%
70,5%
55,3%
79,9%
47,1%
75,9%
33,1%
66,8%
50,7%
52,7%
43,7%
69,9%
52,2%
75,1%
63,1%
69,1%
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LAMPIRAN B
CONTOH PERHITUNGAN
B.1
Perhitungan Produksi Biogas /VS
Dari Tabel A.1.1 diperoleh:
Hari ke-1
B.2
Produksi Biogas
=
7,61 L/hari
VS LCPKS
=
26.474 mg/L
VS Discharge
=
7.616 mg/L
VS Terdegradasi
=
26.474 – 7.616 = 18.858 mg/L
Produksi Biogas/VS
7,61
0,000404 L/mgVS.hari
18858
Perhitungan Laju dekomposisi VS
Laju dekomposisi VS dapat dihitung dengan rumus di bawah ini,
Laju dekomposisi VS
=
VS POME VS DISHARGE
100%
VS POME
Pada sampel dengan rasio recycle sludge 25%
Hari ke-2 :
Dari Tabel A.4 diperoleh :
VS POME
=
23.619 mg/L
VS discharge
=
11.124 mg/L
Laju dekomposisi VS
=
23.619 11.124
100% 52,9%
23.619
47
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B.3
Perhitungan Bilangan Reynold
Bilangan Reynold Akibat Pengadukan
Kecepatan putaran (N)
= 37,5 rpm = 0,625 rps
Diameter Pengaduk tipe gate paddle (Da)
= 30 cm = 0,9842 ft
Densitas sludge (ρ)
= 0,9875 gram/ml = 61,6164 lb/ft3
Viscositas sludge (µ)
= 0,0053 lb/ft.s
Sehingga Bilangan Reynold
=
=
,
,
,
,
= 7.038,29
Brodley, 1998 menyebutkan bahwa pola aliran akibat pengadukan terdapat 3
(tiga) jenis yaitu laminar (Re = 10), transient (10 < Re < 104) dan turbulen (Re =
104), sehingga proses sedimentasi pada gravity thickener dengan pengadukan
37,5 rpm menghasilkan aliran transient (Re = 7.038,29).
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LAMPIRAN C
DOKUMENTASI
Gambar C.1 Rangkaian Peralatan pada Pembangkit Listrik Tenaga Biogas
(PLTBg)
Gambar C.2 Gravity Thickener yang Digunakan dalam Penelitian ini
49
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