Coconut Husk Pellet (CH Pellet) Alternative Utilization of Coconut Fiber Waste

In areas where electricity supply is sufficient and coconut coir waste is abundant, the coconut coir can be further processed into coconut husk pellets (CH pellets). CH pellets are biomass pellets or agro-waste pellets and are not wood pellets because the raw materials are agricultural waste and not woody biomass. Why only areas with adequate electricity supply are recommended for CH pellet production? That is because the production of pellets requires a number of mechanical equipment that is driven by an electric motor such as unit size reduction, drying, pressing into a pellet and so on. When the area is not available or the electricity supply is insufficient, coconut coir which is abundant and tends to pollute the environment is recommended for charcoal production, for more details, please read here. And basically the utilization of coconut coir waste technically can vary but the important thing is that it can still be economical, environmentally friendly and sustainable or in line with the concept of bioeconomy.

CH pellets are the same as EFB pellets which can be used 100% in power plants with fluidized bed combustion (FBC) technology. This is because FBC technology has high flexibility for the types of fuel used including pellets from coconut coir and palm oil empty fruit bunches which incidentally have high potassium and chlorine content. This type of pellet from agricultural waste can also be used in pulverized combustion (PC) technology but with a limited portion or usually with the term cofiring. Cofiring biomass with coal on PC technology up to 10% usually does not require modification on the PC generator. The main reason why CH pellets or EFB pellets cannot be used 100% on a PC is because of the chemical ash (ash chemistry), especially the potassium and chlorine content above. High operating temperatures (> 1000 C) make potassium melt and become deposits in heat exchanger pipes so that it gradually decreases efficiency, while corrosive chlorine will make metals in the plant run out quickly. Whereas in FBC with lower operating temperatures or generally 100-200 C lower than PCs, the ash chemistry of the pellets is not a significant problem.

In order for CH pellets to be more widely used or more widely accepted by the market specifically for PC technology which is more widely used than FBC in power plants, the CH pellet quality must be upgraded by reducing the potassium and chlorine content in the coconut fiber. The way to reduce these two elements is to extract them. Potassium and chlorine extract can then be used as liquid organic fertilizer (LOF). LOF production as well as preparing raw materials for CH pellet production are two productive activities that are in line so that the cost of reducing potassium and chlorine content in coconut fiber can be compensated by the LOF production. The potassium content in coconut fiber is about 10% high and potassium is needed by plants. There are certain variants of potassium fertilizer which are expensive and not subsidized so that the production of LOF will reduce the cost of spending the expensive potassium fertilizer, even in certain plantations the cost of fertilizer is very large and not given subsidies. After the potassium and chlorine content in the coconut husk can be extracted for LOF production, then the coir will become the raw material for CH pellets, and the CH pellet products produced are more leverage in power plants with PC technology.