Techno-Economic Appraisal of Biodiesel

from Jatropha Curcas:

An Egyptian Case Study

by

Prof. Guzine I. El Diwani, Prof.Dr.Shadia Rageb, Prof.Dr. Salwa

Hawash , Dr. Nahed Kamal ,

National Research Centre, Egypt

Chemical Engineering and Pilot Plant Department

Email corresponding author:geldiwani@yahoo.com

And

Prof.Dr. Ihab Farag

Univer. Of New Hampshire, USA

1. Introduction

1- Biodiesel is a fuel made from any vegetable oil

including oils pressed straight from the seeds (virgin

oils) such as soybean, sunflower, canola, coconut and

Jatropha Curcas (JC).

2-It can be produced from any material that contains

fatty acids.

3- Thus, various vegetable fats and oils, animal fats,waste greases, and edible oil processing wastes canbe used as feedstock for biodiesel production.

4- The choice of feedstock is based on several variablessuch as local availability, cost, government supportand performance as a fuel.

5-Biodiesel as a fuel runs in any unmodified dieselengine and it has been shown to give engineperformance generally comparable to that ofconventional diesel fuel while reducing engineemissions of particulates, hydrocarbons and carbonmonoxide .

6- It has been reported that when biodiesel was used,CO was reduced by 8.6%, hydrocarbons by 30.7%,and particulate emissions by 63.3%. However, CO2

emissions were increased by 2.6%and NOx emissionswere increased by 5%.

7- Biodiesel is typically mixed with regular diesel inblends between 5% and 50% (designated by a Bfollowed by the percentage of biodiesel in theblend).

8- Any biodiesel blend (even B100) can be used instandard diesel engines without modification to theengine .

9- There are several benefits for using biodiesel as ablended fuel in diesel engines such that most majorcar and equipment manufactures have issuedstatements certifying that blends up to B20 areacceptable for use in their diesel engines withoutloss of warranty.

10- The economics of biodiesel production fromseveral oil seeds in general and from JC in particularhave been published in several reports issuedworldwide.

11- This work is concerned with the techno-economicappraisal of biodiesel production from JC in Egypt.

12- Although several articles and reports haveaddressed the issue, appraisal under Egyptianconditions is highly needed for application inthe country in addition to providing guidelinesfor adoption under similar conditionsworldwide.

13-The first section includes the technicalaspects as obtained through an extensive R&Dprogram.

14- It is then followed by simulation and basicengineering of the crushing, extraction,transesterification and purification stages.

15-The third section includes the financialaspects and analysis through the formulationand assessment of several scenarios takinginto consideration the productivity of seedsper unit area and the extent of recovery ofraw oil from the JC seeds.

2. Basis of Technical Aspects2.1. Jatropha Curcas Plantation in Egypt.

Jatropha plant is cultivated in different placesin Upper Egypt and in Egyptian deserts.Jatropha trees were irrigated with municipalwastewater primary treated. Averageproductivity for Jatropha fruits was 3.7 tonsfruit /4000 m2 (acre) with average oil recoveryof 25% by weight from seeds.

Start 2002 350 FeddansLuxor

Start 2003250 Feddans

400 Feddans

Sohag

Suez

Start 2006

Start 2009

100 Feddans

4000 Feddans

New Valley

Start 2006

(as study)

2 FeddansAbu Rawash

2.2. Optimum biodiesel production conditions from Jatropha plant.

Through extensive experimental work on bench andpilot scale, optimum operating conditions forJatropha oil and biodiesel production have beenobtained and are taken as the basis for this work asoutlined below.

2.2.1. Jatropha oil Extraction

The extraction process essentially comprisesfruit dehulling, seed crushing to 2 mm,extraction of oil using hexane as solvent atratio 1:5 seeds to hexane and separation ofhexane from oil by hexane evaporation undervacuum at 40°C.

2.2.2. Transesterification

Conditions for transesterification include:

• Use of methanol as alcohol for transesterificationat molar ratio of 6:1 alcohol :oil.

• Use of sodium hydroxide as catalyst at a 0.75% orpotassium hydroxide at a 1% based on oil weight.

• Mix the reaction mixture at 60 rpm for 10minutes and continue mixing for one hour at atemperature 65ºC to complete the reaction.

• 94 – 98% reactant oil conversion to biodiesel isachieved and the overall reaction product is left tosettle in a clarifier for two hours.

• Glycerol is obtained as byproduct at a rate of about10% of produced biodiesel and settled as the lowerphase in the reaction product at 50% purity.

• This lower phase is separated and purified usingphosphoric acid to obtain glycerol 85% purity.

2.2.3. Seed cake evaluation

• a- Seed cake obtained form oil extraction whichconstitutes about 55- 75% of the seed, is dried at 60ºC toeliminate hexane traces; positive results for use asfertilizer have been obtained.

• b- Dried seed cake is also tested animal fodder andproved successful when substituting conventional rabbitfodder by 7.5% and by 30% for gaats. It is to be notedthat the content of phorbol ester of 0.085%, which is thecause of toxicity, can be removed by special treatment.

Further investigations are to be undertaken for treating theseed cake and testing for use as animal fodder.

2.2.4. Treatment and recovery of side – streams

The basic processing steps for biodiesel

Figure (1) Material Balance based on pilot-scale experimental results

3. Techno-economic Aspects for Biodisel Production under Egyptian Conditions 3.1. Capacity of Production Facilities

• Biodiesel is produced in large capacities on the

commercial scale in US and Europe.

• Plants up to 85 million gallons / year (about 275

thousand tons/year) production are in operation in the

US.

• Conversely, in developing countries, biodiesel

production is still on small-scale.

• Within the scope of this work an economic

model and indicators for two nominal annual

capacities namely 8000 and 50000 metric ton

have been developed. The optimum process

conditions, as developed in our laboratory, and

outlined in last section are adopted.

3.2. Simulation and Basic Engineering

• Simulation and basic engineering of

extraction/transesterification of raw oil for the two

proposed capacities has been conducted .

• Simulation has been conducted using ASPENPLUSfrom Aspentech which is the most powerfulsimulation software on the market.

• The software from Haas has been used as a basisafter introducing necessary modifications to adoptedfor the raw materials, process conditions andcapacities proposed in this work.

• The simulation includes the following section:crushing, extraction, transesterification, biodieselpurification and glycerol purification.

• Simulation output including material andenergy balance and specifications of essentialcomponents marked on Figure (2) are outlinedin Table (1) for the 50000 tons/yr productioncapacity.

• Results have been used for the costestimation of capital costs for the twoproposed capacities respectively.

a. Methanol Recovery Column:-

Component Fractions

Outlet streams MEOHREC EST1

Methanol .94000 .59999e-01

Oil .35236e-02 .99648

Biodiesel .18283e-14 1.0000

Glycerol .18901e-15 1.0000

NaOH .11422 .88578

Water .11422 .88578

Summary of key results

Number of stages 7

Top stage temperature c 29.2638

Bottom stage temperature c 65.4330

Top stage liquid flow kmol/hr 73.5179

Bottom stage liquid flow kmol/hr 36.8265

Bottom stage vapor flow kmol/hr 56.9743

Molar reflux ratio 2.00000

Molar boilup ratio 1.54710

Condenser duty (w/o subcool) kw -775.115

Reboiler duty kw 768.907

Oil feed pump:-

Input data:-

Outlet pressure bar 4.00000

Driver efficiency 1.00000

*** Results ***

Volumetric flow rate cum/hr 8.31471

Pressure change bar 3.80000

Npsh available meter 2.33736

Fluid power kw 0.87766

Brake power kw 2.23315

Electricity kw 2.23315

Pump efficiency used 0.39302

Net work required kw 2.23315

Head developed meter 44.4806

b.Biodiesel purification column:-

Component split fractions

Outlet Stream

Meohwat Biodiesel Oilrec

methanol .93710 .62903e-01 .28201e-13

oil .14329e-04 .35854e-02 .99640

biodiesel .63795e-03 .97293 .26429e-01

glycerol .11152 .85827 .30212e-01

naoh .93417 .65830e-01 .95110e-15

water .93417 .65830e-01 .95110e-15

*** summary of key results ***

number of theoretical stages 8

top stage temperature c 154.101

bottom stage temperature c 287.394

top stage liquid flow kmol/hr 23.6998

bottom stage liquid flow kmol/hr 0.79661

top stage vapor flow kmol/hr 1.39521

bottom stage vapor flow kmol/hr 104.632

molar reflux ratio 0.94817

molar boilup ratio 131.346

condenser duty (w/o subcool) kw -2,055.33

reboiler duty kw 2,519.85

c. Glycerol column:-

Component split fractions

outlet streams

watmeoh glycerol

methanol 1.0000 .45499e-05

biodiesel .36749 .63251

glycerol .17395e-01 .98260

water 1.0000 .15490e-08

Summary of key results

top stage temperature c 68.9594

bottom stage temperature c 269.036

top stage liquid flow kmol/hr 65.8132

bottom stage liquid flow kmol/hr 7.68049

bottom stage vapor flow kmol/hr 76.0203

molar reflux ratio 2.00000

molar boilup ratio 9.89785

condenser duty (w/o subcool) kw -1,216.86

reboiler duty kw 1,364.40

Table 1 Material & Energy Balance and Specification Of Essential Components

(2) Flowsheet of the complete crushing/extraction/transesterification process

3.3 Basis of Estimates for the Economic Model:

Option I

In this option I it is assumed that each of theessential processing stages namely plantation,crushing & extraction, and transesterification& purification could be considered as a sub-project and financed separately.

Option II

In this option II it is assumed that the whole project isintegrated i.e. seeds from the plantation stage aredelivered directly to the extraction stage with no profit.Similarly, the raw oil is delivered directly to thetransesterification stage.

All other assumptions are similar to Option I except forsome consequent assumptions such as decrease inworking capital and operating costs corresponding tono direct profits for seeds or raw oil.

The Basic assumptions for both cases are presentedbelow.

Item High Productivity Average Productivity

Ton Fruits Per 4000 m2 (acre) 5.58 3.43

Tons Seed per 4000 m2 (acre) 3.2 2.0

Table (2) Alternative assumptions for high and average productivities of fruits and seeds

Raw Materials-Intermediate Products &

Products/Prices:

Table (3) Estimated prices of Raw Materials and Products Item Price $/ton Basis of Estimates

Hexane 791 Market Price

Methanol 818 Market Price

NaOH 455 Market Price

H3PO4 729 Market Price

Seeds 145-230 Actual production costs *1.25 to account for profits

for the plantation stage)

Raw Oil 300-625 Prices that ensure a Simple Rate of Return on

Investment () for the crushing /extraction stage of 12-

15%

Biodiesel 945 US price (November 2010)

Cake 145 Market Price of equivalent product used as animal

fodder

Glycerol 545 Market Price

Capital Investments

The capital investments for the process components have been estimated as follows

Table (4) Basis of Estimates of Capital Costs

Item % Relative to

Fixed Capital

Purchased Equipment 100 Purchased Equipment*

Equipment Setting 30 Purchased Equipment

Piping 15 Purchased Equipment

Civil 15 Purchased Equipment

Steel 15 Purchased Equipment

Instrumentation 10 Purchased Equipment

Electrical 10 Purchased Equipment

Insulation 8 Purchased Equipment

Paint 8 Purchased Equipment

Other 10 Purchased Equipment

Engineering 10 Total Fixed Capital

Contract Fee 5 Total Fixed Capital

Contingencies 10 Total Fixed Capital

Working Capital 25 Annual Operating Costs

* Prices of Equipment have been estimated from reported sources

Operating Costs:

In addition to raw materials costs as estimated according to actual consumption from pilot experimental results and prevailing costs, other components of operating costs are presented in Table (5).

Table (5) Basis of estimates of operating costs others than raw materials

Labour $/Annum

Engineers 4364

Supervisors 3273

Adminstration 2182

Labourer 1091

Maintenance 2% of Capital

Others 5% of Total Annual Operating Cost

4 Scenarios have been assumed for each Option as depicted in Figure (3)

I

High Productivity

(5.58 ton fruit/acre)

High Recovery

(45% oil )

III

High Productivity

(5.58 ton fruit/acre)

Low Recovery

(25% oil )

IV

Average Productivity

(3.43 ton fruit/acre)

Average Recovery

(35% oil )

II

Average Productivity

(3.43 ton fruit/fed)

High Recovery

(45% oil )

Figure (3)Scenarios for the Two Capacities:8000 & 50000 tons/yr

4. Results and Analysis4.1 Area Requirements:-

The area requirements for the assumedScenarios are presented in Figure (4).

Figure (4) Area Requirements (4000 m2)

0

10000

20000

30000

40000

50000

60000

70000

80000

SC I SC II SCIII SCIV

8000 ton/yr

50000 ton/yr

Raw Materials94%

Labour1%

Maintenance1%

Others5%

Figure (5) Distribution of annual operating costfor SCIII - 50000ton/yr

0

20

40

60

80

100

120

140

160

SC I SC II SC III SC IV

US

D ($

)Figure (7) Financial Indicators for 50000

Ton/Yr Biodiesel

Total Capital Investments Millions

$

Total Production Costs Millions $

Total Profits Millions$

Average SRR%

4.2.3 Distribution of Capital Costs over Processing Stages

The distribution of capital costs for the twocapacities is demonstrated in Figures (8) and(9). Plantation represents the major costcomponent.

Figure(8) Distribution of Capital Costs

Over Processing Stages %

0

10

20

30

40

50

60

70

80

I II III IV

P l a nt a t i on

Cr ushi ng/

Ex t r a c t i on

Tr a nse st e r i f i c a t i on

8000 Ton/yr

Figure (9) Distribution of Capital Costs

Over Processing Stages %

0

10

20

30

40

50

60

70

80

I II III IV

P l a nt a t i on

Cr ushi ng/

Ex t r a c t i on

Tr a nse st e r i f i c a t i on

50.000 Ton/yr

Figure (10) SRR % for Transesterification at

constant biodiesel Price $945/ton

0

50

100

150

200

SC I SC II SCIII SCIV

8000 ton/y r

50000 ton/y r

4.2.5 Prices of Biodiesel for a value of SRR of 10%. (national interest rate)

Table (6) Specific Biodiesel Price for Transesterification (SRR 10%)

SC I SC II SCIII SCIV

Capacity $/ton

8000 ton/yr 459 674 575 781

50000 ton/yr 425 642 541 746

Capacity $/liter

8000 ton/yr 0.41 0.61 0.52 0.70

50000 ton/yr 0.38 0.58 0.49 0.67

4.3 Financial Indicators for Option II

In this option II it is assumed that the whole project isintegrated i.e. seeds from the plantation stage aredelivered directly to the extraction stage with no profit.Similarly, the raw oil is delivered directly to thetransesterification stage.

All other assumptions are similar to Option I except forsome consequent assumptions such as decrease inworking capital and operating costs corresponding to nodirect profits for seeds or raw oil.

Table (7) Economic Indicators for Integrated Scheme – Option II

Annual Biodiesel Production 8000 Tons

SC I SC II SC III SC IV

Total Capital Inv estments $ 11.9 17.6 18.1 21.1

Total Production Costs $ 1.2 1.2 5.5 5.9

Total Profits $ 5.3 4.2 6.3 4.9

Av erage SRR% 44.5 24.0 35.1 23.5

Annual Biodiesel Production 50000 Tons

Item/Scenario SC I SC II SC III SC IV

Total Capital Inv estments Millions $ 65.1 65.1 97.4 119.7

Total Production Costs Millions $ 6.7 6.7 33.9 36.5

Total Profits Millions $ 34.0 27.7 39.8 31.2

Av erage SRR% 52.2 28.4 23.5 26.1

Table (8) Prices of Biodiesel for SRR 10%-Integrated System- Option II

SC I SC II SCIII SCIV

Capacity $/ton

8000 ton/yr 435 656 380 610

50000 ton/yr 396 607 357 584

Capacity $/liter

8000 ton/yr 0.41 0.61 0.52 0.7

50000 ton/yr 0.38 0.58 0.49 0.67

• The SRR varied between 19& 36% and 22 &44 % for 8000 and 50000 ton/annum respectively. Positive economic indicators have also been obtained if it is assumed that all stages are considered as an integrated project.

• The price of biodiesel that provides a SRR of 10 % was in the range of $ 0.3-0.7/liter for the different assumed scenarios which is lower than the prevailing price of biodiesel (about $1/liter)

• Thus, in view of experimental results and economic assumptions, there are positive prospects for production of biodiesel from Jatropha Curcas under Egyptian conditions.