Biodiesel Process Version 1.01

Contents

Tab

BD

GR and MR

MB

EB

Authors: Tapasvi, Wiesenborn, Gustafson, North Dakota State University

Questions: send e-mail to d.wiesenborn@ndsu.edu

DISCLAIMER:

Biodiesel Process Version 1.01

Mass balances, input user-selected inputs, oil composition

Energy balances

Authors: Tapasvi, Wiesenborn, Gustafson, North Dakota State University

Questions: send e-mail to d.wiesenborn@ndsu.edu

Block diagram showing symbols of key units and stream numbering associated with crude oil pretreatment, transesterification, ester washing and drying.

Block diagram showing symbols of key units and stream numbering associated with glycerol recovery and methanol recovery.

The model is based upon published literature and common process engineering assumptions. Every effort has been made to accurately model the biodiesel process. However, this model is intended only as a demonstration of the biodiesel process modeling concept, and has not been fully and systematically tested or checked for errors. Neither the authors nor NDSU will be liable for any damages or loss of profits that may result from use of this biodiesel process model.

Mixing tank (B)

Centrifuge (C)

Crude oil (1)

Mixing tankOutstream (5)

Degummed Oil (9)

Biodiesel Production

Gums-water mix (6)

Heater (A)

Soft water (4)

Gums/Water Separation (D)

NaOH solution (9.5 wt%) (10)

Refining tank (RT)

(E)

Wash (soft) water (11)

Centrifuge (F)

Centrifugeoutstream (14)

Soapstock (13)

Phosphoric acid (3)

Gums (7)

Water (8)

Heatedcrude oil (2)

RTOutstream (12)

CSTR 1 at 60 C (J)

Methanol (20)

Sodium methoxide catalyst (19)

CSTR 1 Outstream (21)

(Methyl esters + glycerol + catalyst + excess methanol)

Separator 1 (Decanter) (K)

Glycerol + methanol + catalyst

CSTR 2 at 60 C (L)

Ester phase (23) Surge tank

(I)Centrifugeoutstream (14)

(10% solution in methanol)

Glycerol phase 1 (22)

Vacuum Oil dryer (H) 35 mm Hg absolute pressure

Water vapor (16)

Hot oil (17)

Refinedoil (18)

Heater (G)

HeaterOutstream (15)

Glycerol + methanol + catalyst

CSTR 2 at 60 C (L)

Methanol (25)

Separator 2 (Decanter) (M)

WashColumns (P)

Wash water (30)

Sodium methoxide catalyst (24)

Washed Esters (33)

Heater (O) Wash water (31)

Waste stream (32)

Ester phase (28)

Glycerol phase 2 (27)

Settler tank (Q)

Ester (35)

Aqueous phase (34)

Collecting tank (T)

Glycerol refining section

Glycerol/Aqueous phase (39)

CSTR 2 Outstream (26)

(Methyl esters + glycerol + catalyst + excess methanol)

Heater (R)

Heater (N)

HeaterOutstream (29)

Glycerol refining section

Methyl esters (Biodiesel) (38)

Vacuumester dryer

(S) 35mm Hgabsolute

pressure

Water vapor (37)

HeaterOutstream (36)

Collecting tank (T)

Heater (U)

Glycerol-alcohol stripper (V)

Glycerine hold tank (Y)

Acidulation Reactor (AR) (Z)

80% glycerine solution (51)

Methanol recoverydistillation column (W)

Decanter(AA)

Glycerol Refining and Methanol Recovery section

Condenser (X)

Glycerol/Aqueous phase (39)

Heater outstream (40)

Methanol saturated vapors + saturated steam (42)

Glycerine (47)

Hot Glycerine solution (46)

Methanol vapors (43)

Super heated steam (41)

Acidulation Reactor (AR) (Z)

80% glycerine solution (51)

Bottoms (44)

Decanter(AA)

Waste (50)(FFA/Unreacted oil)

To transesterification reactors (45)

Glycerol Refining and Methanol Recovery section

Condenser (X)

HCL(48)

AR outstream (49)

11/15/2004 GROSS MASS BALANCE: BIODIESEL PRODUCTION PROCESS(All flows are in Kilograms per day)

Input transesterification efficiency 98

Input the amount of crude oil (Kg/sec) 100

Input methanol/triglyceride ratio 6

Stream 1 2Descr. Crude Heater

Oil Outstream

Component

Water (w)Methanol (mt)Sodium Methoxide (sm)Crude Oil TG (t) 96.000 96.000 FFA (f) 0.800 0.800 Phosphatides (p) 2.000 2.000 Others (Unsaponifiable matter) (o) 1.200 1.200Glycerol (g)Soaps (s)Methyl Ester (me)NaOH (n)Phosphoric acid (pa)HCl (h)Gums (gu)

Steam (st)NaCl (na)

Total (M) 100.000 100.000

Temperature (C) 20.0 70.0Average specific heat (Kj/Kg/C) 1.917 1.917Enthalpy (Kj/Kg) (H) 38.340 134.190Mass*Enthalpy (KW) (M*H/sec) 3834.000 13419.000Phase Liquid Liquid

Fatty acid composition of oils

Fatty acid C 16 C 16:1Triglyceride Molecular weight (gm) 807.339 801.288

Composition of the oil(% age) 11 0Soybean Oil 11 0Canola Oil 4 0.5Molecular weight fraction 88.807 0.000

Molecular weight of the oil 872.869

Components of crude oilSoybean Oil Canola Oil

Triglyceride 96.000 97.250Free fatty acids 0.800 0.500Phosphatides 2.000 1.250Others 1.200 1.000

Molecular weightsg-mole

Molecular weight of oil 872.869Molecular weight of methanol 32.040Molecular weight of glycerol 92.100Molecular weight of methyl esters 292.296Molecular weight of sodium methoxide 54Molecular weight of water 18Molecular weight of NaOH 40Molecular weight of NaCL 58.5Molecular weight of HCL 36.5

Fatty acid C 16 C 16:1Molecular weight (g-mole) 256.4 254.4Soybean oil free fatty acid M.W. (g-mole) 10.256 1.272Canola oil free fatty acid M.W. (g-mole) 28.204 0

Soy FFA M.W (g-mole) 278.22Canola FFA M.W (g-mole) 281.733Molecular weight of the FFA (g-mole) 278.22Molecular weight of soap (g-mole) 278.242

Specific heat Kj/Kg/C

Soybean oil/ Soy biodiesel 1.917Canola Oil/Canola biodiesel 1.913Oil/Biodiesel 1.917

Methanol 2.55Glycerol 2.32Water 4.186

Reactions involved

FFA-NaOH (Alkali refining) RCOOH + NaOH

Amount of soap produced 0.7920626266983Amount of water produced 0.0512400258788Amount of sodium hydroxide consumed 0.11386672417511 (99% FFA removal)

FFA-Sodium methoxide (CSTR 1)

Amount of soap produced 0.00800063259291Amount of methanol produced in CSTR 1 0.00092128531378Amount of sodium methoxide consumed 0.00155272805693

Sodium methoxide-HCL (Acidulation reactor)

Amount of methanol produced 0.63811813333333Amount of sodium chloride produced 0.63811813333333Amount of hydrogen chloride consumed 0.72694481481482

Soap-HCL (Acidulation reactor) RCOONa + HCL

Amount of FFA produced 0.008Amount of sodium chloride produced 0.00168212206168Amount of hydrogen chloride consumed 0.00104952914959

RCOOH + NaOCH3

NaOCH3 + HCL

GROSS MASS BALANCE: BIODIESEL PRODUCTION PROCESS(All flows are in Kilograms per day)

3 4Phosphoric Soft

acid watersolution

0.015 1.500

0.085

0.100 1.500

C 18 C 18:1891.501 885.453

4 234 232 60

35.660 203.654

C 18 C 18:1284.4 282.45.688 169.44

11.376 64.952

RCOONa + H2O

0.115016893106175 (100% FFA removal)

RCOOH + NaCL

RCOONa + CH3OH

CH3OH + NaCL

GROSS MASS BALANCE: BIODIESEL PRODUCTION PROCESS

5 6 7 8 9Mixing tank Gums-water Gums Water Degummed Outstream mix Oil

1.515 1.507 1.507 0.008

96.000 0.480 0.480 95.5200.800 0.8000.000 0.0001.200 1.200

2.085 2.085 2.085

101.600 4.072 2.565 1.507 97.528

20.01.917

38.3403739.207

Liquid

C 18:2 C 18:3 C 20 C 22 C 22:1879.405 873.357 975.678 1059.828 1053.798

54 8 0 0 054 8 0 0 020 10.5 1.5 0 1.5

474.879 69.869 0.000 0.000 0.000

C 18:2 C 18:3 C 20 C 22 C 22:1280.4 278.4 312.5 340.5 338.556.08 29.232 4.6875 0 5.0775

151.416 22.272 0 0 0

(100% FFA removal)

10 11 12 13 14NaOH Wash Refining tank Waste Centrifuge

Solution water Outstream Outstream

2.334 15.000 17.393 17.306 0.087

95.520 2.000 93.5200.008 0.0080.000 0.0001.200 0.030 1.170

0.792 0.792

0.245 0.131 0.131

2.579 15.000 115.044 20.259 94.785

20.0 20.0 70.0 70.04.184 4.186 2.262 1.919

83.680 83.720 158.362 134.336215.794 1255.800 18218.573 12733.007Liquid Liquid Liquid Liquid

C 241143.996

000

0.000

C 24 M.W of 1 kg-mole368.6

0 0.2817330 0.27822

15 16 17 18 19Heater Water vapor Hot Oil Refined Oil Catalyst

Outstream recovered 2 in CSTR 1

0.087 0.0878.4170.935

93.520 93.520 93.5200.008 0.008 0.0080.000 0.000 0.0001.170 1.170 1.170

94.785 0.087 94.698 94.698 9.352

90.0 90.0 90.0 20.0 20.01.919 1.940 1.917 1.917 2.550

172.717 174.600 172.530 38.340 51.00016371.008 15.184 16338.246 3630.721 476.952

Liquid Vapor Liquid Liquid Liquid

20 21 22 23 24 25Methanol CSTR 1 Glycerol phase 1 Ester phase Catalyst Methanolin CSTR 1 Outstream in CSTR 2 in CSTR 2

12.180 11.655 6.993 4.662 1.263 1.8270.935 0.935 0.140

14.028 14.0280.000 0.0000.000 0.0001.170 1.1708.388 8.3880.008 0.001 0.007

79.858 79.858

12.180 116.042 16.317 99.725 1.403 1.827

20.0 60.0 55.0 20.0 20.02.550 2.015 1.947 2.550 2.550

51.000 120.888 107.063 51.000 51.000621.179 14028.121 10676.846 71.543 93.177Liquid Liquid Liquid Liquid Liquid

26 27 28 29 30 31CSTR 2 Glycerol phase 2 Ester phase Heater Wash water Heater

Outstream Outstream outstream

18.414 18.4146.413 3.848 2.565 2.565

0.140

0.281 0.281 0.2810.000 0.000 0.0000.000 0.000 0.0001.170 1.170 1.1701.283 1.2830.007 0.001 0.006 0.006

92.072 92.072 92.072

101.225 5.271 96.094 96.094 18.414 18.414

60.0 20.0 70.0 20.0 70.01.962 1.934 1.934 4.186 4.186

117.733 38.678 135.373 83.720 293.02011917.472 3716.711 13008.490 1541.648 5395.769

Liquid Liquid Liquid Liquid Liquid

32 33 34 35 36Waste stream Washed Aqueous phase Esters Heater

Esters Outstream

16.573 1.841 1.749 0.092 0.0922.565

0.281 0.281 0.2810.000 0.000 0.0000.000 0.000 0.0001.170 1.170 1.170

0.00692.072 92.072 92.072

19.144 95.364 1.749 93.614 93.614

60.0 951.890 1.890

113.372 179.50510613.211 16804.250

Liquid Liquid

37 38 39 40 41Water vapor Methyl esters Glycerol/Aqueous Heater Super-heated

(Biodiesel) phase Outstream Steam

0.092 18.322 18.32213.406 13.4061.075 1.075

0.2810.0000.0001.170

9.670 9.6700.008 0.008

92.072

80.266

0.092 93.522 42.482 42.482 80.266

95.0 95.0 20.0 64.5 250.01.940 1.917 3.203 3.203

184.300 182.115 64.063 206.602 2973.87016.969 17031.805 2721.493 8776.814 238700.818Vapor Liquid Liquid Liquid Vapor

42 43 44 45 46 47Methanol-Steam Methanol Bottoms Methanol Hot Glycerine

Vapors Vapors glycerineSaturated solution

18.322 18.32213.406 13.339 0.067 13.339

1.075 1.075

9.670 9.6700.008 0.008

80.266

111.994 13.339 18.389 13.339 10.754 10.754

100.08 100.082.343

3430.190 234.467279468.622 2521.414

Vapor Liquid

48 49 50 51HCL Acidulation Waste Glycerine

reactor (FFA/Unreacted Oil)outstreamoutstream

4.570 4.5700.638 0.638

0.008 0.008

9.670 9.670

0.807 0.079

0.640

5.377 15.605 0.008 10.308

Energy Balance

Steam (Kg/sec)

Energy Balance

Heat energy required (Q) (KW) (Kcal/sec)

(Saturated steam at 180 C, 150 psi pressure)(Difference between steam and condensate)

(3 mbar gauge pressure, 250 C)

Latent heat of vaporizationWater at 100.084 CMethanol at 64.5 C

Methanol Distillation Column Reboiler duty (KJ)(Adapted from NREL report) (Kcal)(53,676 Kcal per 1000 kg biodiesel produced)

Evaporation energy of the saturated steam (Kj/Kg) [hg-hl]

Available energy from the super-heated steam (Kj/Kg) [hsh-hg]

Heater (A)

4.757

9585.0002290.87

2015.00

717.43(Saturation temperature = 100.084 C)

Kj/kg2256.441008.00

21003.265019.90

M1H1 + Q = M2H2

M1H1 M2H2

Q

Retention tank (E)

6.455

13007.7713108.93

M9H9 + M10H10 + M11H11 + Q = M12H12

M9H9 M12H12

Q

M10H10

M11H11

Heater (G)

1.805

3638.002869.50

M14H14 + Q = M15H15

M14H14 M15H15

Q

CSTR 1 (J)

4.615

9299.2692222.58

M18H18 + M19H19 + M20H20 + Q = M21H21

M18H18M21H21

Q

M20H20

M19H19

CSTR 2 (L)

0.534

1075.906257.15 #VALUE!

M23H23 + M24H24 + M25H25 + Q = M26H26

M23H23M26H26

Q

M25H25

M24H24

Heater (N)

4.611

9291.7792220.79

M28H28 + Q = M29H29

M28H28M29H29

Q

M26H26

Heater (O)

1.913

3854.121921.16

M30H30 + Q = M31H31

M30H30M31H31

Q

Heater (R)

5.267

10613.2112536.62

M35H35 + Q = M36H36

M35H35 M36H36

Q

Heater (U)

3.005

6055.3221447.26

M39H39 + Q = M40H40

M39H39M40H40

Q

Glycerol-alcohol stripper (V)

80.266

43289.21810346.37

M40H40 + M41H41 (=Q) = M42H42 + M46H46

M40H40 M46H46

M42H42

M41H41

Satuated steam required (Kg)

43.386

Super-heated steam required (Kg)

80.266