The Urgency of Biochar Application on Palm Oil Plantations in Indonesia

The large number of acidic soils in Indonesia that are used for palm oil plantations makes the productivity of palm oil fruit or the resulting FFB (fresh fruit bunch) not optimal. The acid soil covers the largest dryland area in Indonesia. It occupies approximately 55% of the total land area (191.09 million ha) in Indonesia. About 107.36 million ha of all Indonesian acid soils is classified as dryland acid soils and the rest (14.93 million ha) as peat soil. Acid soils in Indonesia are distributed amongst the big islands, such as Kalimantan (39.42%), Sumatera (28.81%), Papua (18.03%), Java (7.77%), and Sulawesi (6.95%). Acidic soils with low pH make nutrient absorption low in plants and so do soil microbial activity, which plays a large role in soil fertility. This condition should not be ignored because besides making the cultivation of palm oil plantations not optimal, there will also be a lot of fertilizer used. This makes the operational costs of  palm oil plantation operation high. Biochar is a biomass pyrolysis product that is effective and efficient in overcoming these problems. With the abundant amount of biomass waste produced by palm oil mills or CPO mills as biochar raw materials, efforts to improve the quality of plantation soil should be easy to do and have even become the operational standard for these plantations. But the fact is not.

 

Why hasn't biochar been used to improve soil quality and thus increase the production of palm oil fruit or FFB? The lack of information and education about the benefits and uses of biochar are the main factor. This of course makes the application of biochar in palm oil plantations not yet done even though palm oil mills have abundant biomass waste such as empty palm fruit bunches (EFB) and fiber which are generally not used and cause environmental problems. The priority for processing EFB compared to other products such as EFB pellets or compost also needs separate considerations. The best choice, of course, is based on a comprehensive study according to the characteristics of the business or business will be built. Consider not only short-term economic benefits, but also environmental and long-term benefits is an important thing.

Quantitatively, an increase in the production of palm oil fruit or FFB, an increase of at least 20% with the application of biochar is something that is normal. And a 20% increase in fruit production will also result in a big profit. Productivity of a number of other agricultural commodities can be increased by 30%, 40% or even more than 100%. The low productivity of palm oil fruit in Indonesia can be increased by the application of biochar, which is particularly effective in improving the soil quality in the palm oil plantations. Moreover, about 80% of the components of the cost of producing crude palm oil (CPO) come from the plantations, and 20% in the processing sector (palm oil mills). The operational costs of palm oil mill plantations, especially fertilizers, can also be reduced by the use of biochar. The priority of liquid biofuel development will also get better if the volume of biofuel raw materials such as CPO increases. This shows the strategic role of biochar. Apart from that from the aspect of climate change, biochar will also absorb CO2 concentrations in the atmosphere or reduce the concentration of greenhouse gases, as a solution to today's world problems. 

 

Meanwhile, from the side of the palm oil mill, another advantage obtained from biochar production is the use of excess energy from the pyrolysis process or the production of biochar as an energy source for the boiler. Boiler feed water (BFW) will also be preheated twice when it is used for cooling in the pyrolysis condenser and then the economizer on the boiler. In this way, the energy needed by the boiler decreases. When the boiler energy source uses the energy source from pyrolysis, this means that the palm kernel shell (PKS) can be taken and used for other things and can even be sold directly for local and export markets. The main obstacle to business development in the palm oil industry is the availability of energy source namely electricity. If the energy source is available, the development of palm oil-based businesses is very open and varied, such as the production of CPO derivatives, palm kernel shell processing, PKO production, PKO derivative production, biomass power plants and so on.

Increasing Energy Efficiency in Palm Oil Mill Operations Using Pyrolysis

Energy utilization in the form of steam production which is then used for electricity production through steam turbines and generators, as well as the use of steam for steamming (sterilizing) fresh fruit bunches (FFB) are the main things in palm oil mill operations. This is because the need for electrical energy to power various mechanical equipment in the mill comes entirely from this electricity production. Electricity and steam for industrial processing are grouped under the utilities that support that industry. Meanwhile, in the sterilization process or the boiling of FFB, steam besides stopping the development of FFA (free fatty acid) and facilitating the threshing will also facilitate the CPO extraction process and processing the kernel (palm kernel). To produce steam and electricity, of course, energy is needed, namely heat. Steam is produced by the boiler in the form of superheated steam to drive steam turbines and generators to produce electricity and then steam from electricity production or low pressure steam is used for steamming (sterilization) of FFB.

The water after being treated so that it becomes BFW (boiler feed water) is then used for the production of steam and electricity. Heat energy to produce steam can be reduced in such a way with the use of a pyrolysis process (which means that it is not ordinary combustion), so that the heat requirement for the boiler furnace is getting smaller. The pyrolysis condenser will produce hot water so that it becomes preheating for the boiler. In pyrolysis a condenser is used to separate bioil and syngas (uncondensable gas). Preheating from the condensation process of the pyrolysis unit will then go to stage 2 preheating in the economizer of the boiler unit. Thus the temperature of the water entering the upper drum on the boiler is high enough, and the heat requirement to become superheated steam will be reduced. The palm oil mill uses a water tube type boiler as is commonly used in large industries and not a fire tube which is in the form of a shell and tube type heat exchanger with the tube submerged in water so that it does not overheat. In a water tube type boiler, it consists of an upper and lower drum (mud drum) which is connected to a pipe. The lower drum and water tube are fully filled with water, while the upper drum is only partially filled. With this arrangement, steam will pass through the mechanical separator on the upper drum, flow to the superheater and exit the boiler. Efficiency is the key word in production, including the use of energy in the production process of CPO or palm oil mills. The rule of thumb is an increase of 10 C in BFW is equivalent to increasing 1% boiler efficiency.

Typical of water tube boiler

Excess energy from the pyrolysis process should be used for fuel or energy sources in the boiler furnace. The use of excess energy from pyrolysis will also produce environmentally friendly flue gas emissions because the combustion of liquid and gaseous fuels will be cleaner than solid fuels. In this way, the palm kernel shell, which has been used for boiler fuel, can no longer be used. All these palm kernel shells or PKS can be sold directly and even exported to Japan and Korea. Of course, be a separate source of additional income. Palm kernel shells or PKS are competitors for wood pellets in the global market because they have many similar properties, but because palm kernel shells come from waste or palm oil mill sideproducts, the price can be cheaper, more information can be read here. The use of slow pyrolysis for biochar production is the best option compared to similar technologies such as fast pyrolysis and gasification, more details can be read here. Palm oil mills or companies will get a lot of benefits from biochar production, for more details can be read here.