Fertilizer Savings in Palm Oil Plantations with Biochar and Compost from Biogas Waste

Although Indonesia is the largest CPO producer in the world with an area of ​​approximately 13 million hectares of palm oil plantations, but it is estimated that less than 10% have a biogas facility from POME (Palm oil mill effluent). Whereas by utilizing POME for biogas production, besides being able to be converted into electricity or heat, it also produces organic fertilizer in the form of compost and liquid organic fertilizer. The compost can be used as fertilizer in oil palm plantations, where the cost of fertilizer for palm oil operations is the highest cost component. It is estimated that every 10,000 hectares costs approximately Rp. 35.75 billion (around US$ 2.25 million) for fertilizer and for more details, you can read here. The use of compost will certainly reduce the need for fertilizer.

Palm oil utilization scheme for optimizing CPO production

Besides that, solid wastes such as palm oil empty fruit bunch, fiber and palm oil frond are also very potential for the production of energy (electricity and heat) and biochar. Energy production in the form of electricity and heat is by burning pyrolysis byproducts in the form of syngas and biooil into the furnace to heat the boiler. And because the syngas and liquid fuels used in the furnace, so that the combustion process is more perfect and clean emissions. Steam generated from the boiler will then drive the steam turbine and generator so as to produce electricity. Low pressure steam from steam turbine is then used for sterilization or boiling the fresh fruit bunches (FFB). While biochar will be used together with compost and chemical fertilizers to make fertilizer effective in the palm oil plantations so that it becomes a slow release fertilizer. Costs for fertilization are also expected to be significantly reduced, for example by up to 50% by this way. Although biochar is not a fertilizer, it has a function that makes fertilizer use effectively because it holds fertilizer nutrients from leaching, for example from rain water, also maintains moisture and so on.

PKS loading for export in Indonesia

PKS (palm kernel shell) can even be sold or exported. This is because previously or in general the palm kernel shells used to fuel boilers with fiber, have been substituted with products from the pyrolysis process namely syngas and biooil. The need for palm kernel shells for both the domestic / local and export markets continues to increase all the time. Palm kernel shells / PKS are environmentally friendly fuels because they come from biomass so they are carbon neutral fuels. The use of PKS as a fuel is widely used by a number of industries starting as a heat source for the drying process such as spray dryers in detergent and ceramic plants, boilers in food industries such as soy sauce factory, to power plants such as in Japan, can be read in more detail here. In the world of biomass fuel commodity trading, especially in the international market, PKS is the main competitor of wood pellets. Although the specifications are not much different, the price of PKS is also cheaper because it comes from palm oil mill waste and does not need complex processing units such as wood pellets. And basically with the scheme of utilizing palm oil mill wastes as above, it will maximize the profit from the palm oil mill or CPO mill.

Business Model Utilization of Palm Oil Empty Fruit Bunches to Maximize the Profit of the Palm Oil Industry

Palm oil empty fruit bunches  (EFB) are still a problem for the palm oil mills in general. The scenario of utilizing palm oil EFB as the goal should be able to cope well with the environment and provide economic benefits. Overcoming environmental problems is clearly a top priority and must be met, but the best use of EFB scenarios should also benefit the environment, both short term and even long term. Likewise for economic benefits, economic benefits should also be obtained in line with these environmental benefits, not counterproductive. That is the best scenario for the use of palm oil EFB, which is currently still a problem.

Palm oil plantations are the production base for palm oil mills, both CPO mills and PKO mills. Without the palm fruit produced from the palm oil plantation, the palm oil mill will not be able to produce. Operation of palm oil plantations is indeed not an easy and expensive thing. This is mainly a factor of the large usage fertilizer demand, so as to reach around 60% for the operation of the palm oil plantations themselves or with an area of ​​20,000 hectares of palm oil plantations, the cost needs reach more than 70 billion rupiahs ( (around US$ 4,766,667), for more details, please read here. The factor to reduce the cost of fertilizer and maintain the productivity of palm oil fruits or fresh fruit bunches and even increase them is the main target for the utilization or processing of palm oil  EFB. If the cost of palm oil plantation operations can be reduced, the greater the benefits. Biochar is a palm oil EFB processing product that can be used to reduce fertilizer requirements in the palm oil plantation. Biochar production using pyrolysis as shown below.

 

In the process of pyrolysis, besides producing the main product in the form of biochar, then biooil and syngas are also produced. The biooil and syngas are then used as fuel generator to produce electricity. In palm oil mills or CPO mills, fiber waste is also commonly found. The fiber waste is often just piled up and never utilized so it tends to pollute the environment. Though these fibers can be made pellets for export and become fuel for power plants. In addition, currently millions of hectares of old palm oil plantations in Indonesia need to be immediately replanting. Millions of tons of old oil palm trunks are also potential for pellet production. If old oil palm trunks are only left in the plantation so they rot and decay, then it will become lava media and subsequently become a beetle which actually disrupts productive palm oil plantations as well as other plantations, for more details read here. The production of pellets from fiber or palm trunks requires electricity and this can be supplied from the pyrolysis of palm oil EFB like the scheme above. Although palm oil mills also produce electricity, but generally only for the purpose of CPO production, so it is not enough for the production of fiber pellets and oil palm trunk pellets (OPT pellets).

Palm Kernel Shell Continuous Pyrolysis For Multipurpose Production

Production of palm kernel shells (PKS) which is palm oil mill waste in Indonesia approximately 9 million tons. Current utilization of 20% (1.8 million tons) for export, 15% (1.35 million tons) for internal use, 10% (0.9 million tons) for domestic (local) use, and the remaining 55% (4.95 million tons) yet used or become waste. Meanwhile, Indonesia's CPO production currently reaches 35.2 million tons, or 20% of FFB (Fresh Fruit Bunch), so the number of FFB (Fresh Fruit Bunch) produced in Indonesia currently ranges from 176 million tons. With an average productivity of 20 tons / hectare of FFB, so the FFB is generated from 8.8 million hectares. While the total area of ​​oil palm plantations in Indonesia is currently estimated to have almost 12 million hectares including unfruitful and unproductive age or need to be replanting. Another influential factor is the low level of productivity of oil palm plantations. Palm kernel shells are only about 6% of the FFB produced, and after is used for the internal CPO production process in the mill  with mesocarp, only about 4.5% of the palm kernel shell is the waste of the palm factory. From there it can also be calculated that every hectare of oil palm plantation will produce 1.2 tons or three quarters namely 0.9 tons of waste. With the current expansion of oil palm plantations up to 12 million hectares, the potential of palm kernel shells that become waste in the palm oil plant around 10.8 million tons or the amount of 10.8 million tons that can be used for export, fuel and production of various other products or external use.

Currently, there are a number of parties who have utilized the palm kernel shells for electricity production and boilers of some industries that are estimated to be less than 10% of the total produced palm shells. Some converting technologies into heat and electricity are used for processing such palm kernel shells. Combustion and gasification are technologies commonly used to convert or extract palm kernel shells into heat and electricity. Combustion technology in the furnace then combined ORC (Organic Rankine Cycle) and Stirling engine to convert it into electricity. While the gas from gasification is then used as fuel in gas engine to generate electricity. Are there any other options for processing the palm kernel shell so that it has bigger added value or more profitable?

Palm kernel shells are not suitable for biogas production because the lignoselulose material or rich lignin content material making it difficult to biologically decompose. The choice is pyrolysis or thermal decomposition with absence of oxygen. Pyrolysis is a technology that can to produce charcoal, biooil, pyro acid and syngas. This is what makes it possible for multipurpose production. Palm kernel shells such as rice husks, sawdust and the like are bulk materials also so will be suitable for continuous pyrolysis. How come? The answer is because there are several options for using the continuous pyrolysis:

1. Production of electricity and charcoal 

2. Production of electricity and activated charcoal

3. Production of electricity and charcoal briquettes

4. Production of charcoal and bio-chemicals

5. Production of charcoal and biofuel

6. Production of Charcoal and heat

At the production of electricity and charcoal, the process of excess syngas is used for electricity production, and charcoal is also produced as a solid product of pyrolysis. The charcoal can also be made briquette so it will be efficient during transportation and its use. As for the production of electricity and activated carbon, then excess syngas is used for the process of activation of the charcoal produced, with a more detailed explanation can be read here. In addition to charcoal, bio-chemicals such as acetic acid, methanol and phenol can also be produced by processing further byproducts namely pyro acid and syngas. Biofuels namely, biooil and syngas can also be additional products besides charcoal. Syngas can also be packed in a tube for ease of distribution and usage. Meanwhile, if syngas and biooil are burned it will generate heat, so if the business of charcoal production in combination with agriculture such as the use of green house or also farms that require a warm certain temperature the continuous pyrolysis unit becomes also very effective to be used. 

Charcoal production from palm kernel shells can also be a solution to the high export tax of palm kernel shells. By processing it into finished product then the tax should be decreased even eliminated because there has been industrialization which also absorb labor and encourage economic growth. In private power producers or IPP (Independent Power Producer), the additional product namely of charcoal will provide an increase business revenue, so that their business becomes more attractive business. In addition to charcoal production, if you want the production of high quality solid fuel (solid biomass fuel) namely by upgrading or processing it with torrefaction, can be done also with pyrolysis technology.