Palm Oil Biomass

CURRENT UTILIZATION

Today, Sarawak is the last frontier of oil palm development in Malaysia as land resources in Peninsular Malaysia is depleting while in Sabah oil palm development had reached its plateau. The total oil palm planted area in Sarawak Malaysia increased by 23.6 % to 4.49 million hectares in 2008 from 3.63 million tons in 2005. The production of fresh fruit bunch increased further by 43 % to 8.88 million tons in 2008 from 6.20 million tons in 2005.

In the process to extract crude palm oil and palm kernel from the fresh fruit bunch (FFB), considerable amounts of by-products such as fiber, shell, empty fruit bunch (EFB) and palm oil mill effluent are also generated as shown in Table below. These residues are the main energy resources that can be processed and converted to useful energies such as electricity, steam and heat.

Products / Residues

Typical mass produced per ton of FFB processed

Description

Primary products

 

Palm Oil

 

220 kg

A fine oil used for cooking and food production, further processing for soap production and olefins

Palm oil Kernel

60 kg

Processed to produce high grade oil

Residual materials

Empty Fruit Bunches (EFB)

 

220 kg

A woody fibrous biomass in units of approx. 65 by 30 cm. Disposal methods varies by country and region.

Shell

55 kg

A hard, solid biomass with high calorific value. Some used as fuel, some disposed e.g. landfill and road bases.

Fiber

130 kg

A fibrous biomass often used in the palm oil mills for boiler fuel for process steam and electricity.

Palm Oil Mill Effluent (POME)

650 kg

A dilute liquid effluent that requires processing prior to discharge to watercourses.

Table: Typical quantities of products and residues per ton of FFB

Figure below shows the current situation in palm oil mills in Sarawak, where the power generated for the mills are from the fiber and shell only. Even then the amount used is significantly smaller compared to the actual amount produced annually. Apart from producing the electricity to the mill, the steam is also used in the sterilization of fresh fruit bunch. EFB and POME are not being utilized for power generation. Only a small amount of EFB is being returned to the plantation for soil mulching while CH4 from POME is being released to the atmosphere.

Figure: Current utilization of POB in Sarawak

 

CURRENT AND FUTURE POTENTIAL

Table below illustrates the potential power generation from POB in Sarawak with a total yearly processing capacity of 9,288,000 tons of FFB in 2008 from 41 mills shown in the following Figure.

Production (ton)

Residue

Residue Producr Ratio (%)

Residue Generated (ton)

Total Potential Energy (MJ)

Potential Electricity Generation (MW)

9,288,000

EFB at 65%MC
Fiber at 50%MC
Shell at 10%MC
TOTAL OPW
POME

22.0
13.0
5.5
40.5
65.0

2,043,360
1,207,440
510,840
3,761,640
6,037,200

1,406,093
1,258,991
1,098,423
3,763,507
379,048

125
112
98
335
40

Table: Potential power generation from palm oil residues

 

Figure: Distribution of palm oil mills in Sarawak (2008)

The divisional production of FFB and POB are shown in Figure A and Figure B respectively while the divisional power potential from POB is shown in Figure C. The total power potential from POB can be seen in Figure D where it shows 375 MW is possible including the mills/plants consumption of 1-2 MW per mill. Presently, an additional capacity of 1,074,000 tons of FFB from 8 mills is under planning and construction in which will increase the total potential of biomass for power generation in near future.


Figure A: Production of FFB in Sarawak 2008 (ton/yr)


Figure B: Production of palm oil biomass in Sarawak 2008


Figure C: Potential power from POM in Sarawak 2008


Figure D: Pyrolytic gasification

 

 

Year

Area (Ha)

 

FFB Yield (ton/ha)

 

FFB Production (ton)

Power Output (MW)

Total Capacity (MW)

FFB

Fiber

Shell

POME

2008

569,196

16

8,876,540

119

107

93

38

 

357.95

 

2009

626,116

17

10,643,972

143

128

112

46

 

429.22

 

2010

688,728

18

12,397,104

167

149

130

53

 

499.92

 

2011

757,601

19

14,394,419

194

173

151

62

 

580.46

 

2012

833,361

20

16,667,220

224

201

175

72

 

672.12

 

2013

916,697

21

19,250,637

259

232

202

83

 

776.29

 

2014

1,008,367

22

22,184,074

299

267

233

96

 

894.59

 

2015

1,109,304

23

25,513,992

343

307

268

110

 

1,028.87

 

2016

1,220,234

24

29,285,616

394

353

308

126

 

1,180.96

 

2017

1,342,257

25

33,556,425

452

404

353

145

 

1,353.18

 

2018

1,476,483

26

38,388,558

517

463

404

165

 

1,548.04

 

2019

1,624,131

27

43,851,537

590

528

461

189

 

1,768.34

 

2020

1,786,544

28

50,023,232

673

603

526

215

 

2,017.22

 

Table: Projection of total power output from palm oil biomass until 2020


Average annual growth in planted areas for the 2006 – 2008 is 11 %. For the computation shown in Table above, 10 % of annual growth is applied. Immature plantation areas are excluded. Only mature plantation areas are accounted for the FFB production. The annual growth of FFB yield is escalated at 1 ton/ha. Sabah recorded a 23 ton/ha yield while Melaka 25.6 ton/ha yield in 2008. According to MPOB, FFB yield could reach 30 %. Conservative thermal efficiency at 32 % and 38 % for POME are assumed throughout the 12 years. A total potential of 500 MW in 2010 and 1,000 MW in 2015 are possible. This will further possess a total potential of 2,000 MW in 2020.
 

EMPTY FRUIT BUNCHES (EFB) AS FUEL FOR POWER GENERATION

There are compelling reasons for supporting the use of empty fruit bunches (EFB) as a source of fuel for renewable energy (RE) power generation. Although the current use of EFB as mulch does have financial benefits, there are better financial gains, with a number of other advantages when used as a fuel for RE power generation. The rapid depletion of fossil fuel needs an alternative replacement and most developed nations are pursuing the development of biomass as an alternative method of power generation.

At 65 % moisture content, EFB has a calorific value of 6028 kJ/kg. The heat content of 1 ton EFB = 6,028 x 1,000 kJ = 6 028 000 kJ. A boiler generating steam at 42 bar absolute (bara) with a high temperature of 500 ºC and a condensing turbine operating in a pressure range between 42 bara and 0.035 bara can give a Rankine efficiency of 39.8 %. The actual thermal efficiency generally is 84 % of this. Even if it is assumed the actual cycle efficiency to be 80 % of the Rankine efficiency, the thermal efficiency is 32 %.

However, in this analysis, the overall thermal efficiency is assumed to be only 25 % for power output. Thus, 1 ton of EFB with 65 % moisture should deliver 6,028,000 x 0.25 kJ = 1,507,000 kJ of energy.


1,507,000 kJ = 1,507,000 / 3,600 kWh = 418.6 kWh

Assuming the minimum price offered by SEB for a unit of electricity is RM 0.21. The gross income will be RM 89.90. Allowing 30 % operational and maintenance cost, the net revenue will be RM 61.50. However, one ton of EFB when used as mulch was found to be RM 14.40. This figure includes all the benefits as a fertilizer as well as the increased FFB yields resulting from using EFB to supplement fertilizer cost.

 

PALM OIL BIOMASS BRIQUETTES

Palm oil industry generates vast amount of palm biomass. However a considerable portion of this biomass is not feasible to contribute for commercial power generation due to the logistic concerns. Therefore, converting palm biomass from scattered estates into a uniform and solid fuel called “Biomass Briquettes” through condensing process appears to be an attractive solution in upgrading its properties and add value. Palm biomass briquette could be the ideal renewable energy fuel source for co-firing in our coal-fired power plants.

The raw materials including empty fruit bunch (EFB), in powder and fiber forms and palm kernel were compressed into briquettes at high temperature and pressure using screw extrusion technology. It was found that briquettes made either from 100 % pulverized EFB or mixed with sawdust exhibited good burning properties. EFB fiber and palm kernel, due to their physical properties, were recommended to be blended with sawdust in producing quality briquettes. Basically, converting palm biomass into briquettes has increased its energy content and reduced moisture content about minimum of 5 % and 38 % respectively compared to its raw materials.

 

FOSSIL FUEL REPLACEMENT AND CO2 REDUCTION ANALYSIS

Type of Power Plant

Capacity MWe

Fuel 1

Fuel 2

Coal Replaced (ton/y)

CO2 avoided (ton/y)

 

10
(small scale)

Biomass
(100%)

Coal
(0%)

52,560

118,260

 

110**

Coal (100%)

-

 

 

Coal
(90%)

Biomass
(10%)

50,000

112,500

Coal
(80%)

Biomass
(20%)

100,000

225,000

Table: Fossil fuel replacement & CO2 reduction

 

Calculation derived from the data of SPC Phase 2 (2008) (**) – Generation versus coal consumption is shown in Table 1.5.5. The total coal consumption for 110 MWe Coal-fired plants was about 500,000 tons in 2008 with energy output of about 750,000 MWh. The caloric value (CV) for coal is approximately three times of biomass’s CV (EFB). Therefore, it is anticipated that about three times of biomass volume, in particular EFB will be required to replace each ton of coal. The CO2 emission is 1.5 t CO2/MWh or 2.25 tons of CO2 per ton of coal.

For a typical 10 MW (*) EFB power plant, with 7,884 hours of operation per annum, the total coal shall be replaced is estimated at 52,560 tons per year with 118,260 tons of CO2 could be avoided. The benefits of reducing CO2 emission by replacing proportion amount of coal with biomass are also factoring the feasibility of implementation of co-firing project. Assuming 1 ton CO2 (1 CER) is traded at RM 30, the total revenue from carbon credit through CDM will be ranged from RM 3 million to RM 7 million of revenue per year for 10 % to 20 % of coal replacement with biomass fuel.