Indonesia is the largest cashew nut producer in the world after India, Vietnam, East Africa, West Africa and Brazil. Cashew nut production in Indonesia is estimated at 131,302 tons and is distributed to a number of production centers, including Central Java, Yogyakarta, East Java, Bali, West Nusa Tenggara, East Nusa Tenggara, Central Sulawesi, Southeast Sulawesi and Maluku province. The thing that is still unfortunate is that most of the cashew nut production in Indonesia is still in raw or spindle (cashew with shell / cashew in shell) which reaches 60% or 78,781 tons, and not in processed products such as peeled (cashew without shell) even ready for consumption. To increase the added value, the cashew produced should be processed first. With this treatment, side product will be produced or waste in the form of cashew nut shell. With Indonesia's cashew production of 131,302 tons, the potential of cashew nut shell produced reaches 52,520.8 tons (40% of cashew). Although cashew nut shells can be used directly for fuel as well as firewood, but if processed will also provide interesting added value.
The cashew nut shell can be processed into cashew nut shell liquid (CNSL) and charcoal briquette. To obtain CNSL, mechanical extraction is done so that the oil and solids are separated. The oil or CNSL has many benefits because it can be used for a variety of industrial raw materials, such as vegetable pesticides, wood preservatives, car and aircraft brake oil, for industrial paints, anti-rust, lacquer, cable wrapping materials, making vehicle brake linings motorized, as a fuel (which is renewable), and renewable adhesives for the wood industry. The yield of cashew oil to cashew shells is around 20%, which means that every ton of cashew shells produces 200 kg of cashew shell oil (CNSL), which is quite a lot and gives added value economically. While the cashew shells are then compressed into briquettes and followed by a carbonization process. The quality of the charcoal briquettes produced by the above process route will also be better compared to the way the charcoal is made first and then compressed into briquette with additional adhesive.
The processing of cashew nuts into products that are ready for consumption requires energy for the production process. In many industries, energy or fuel is a high cost component, so energy saving efforts are very common in many industries. In the process of carbonization or charcoaling the briquetting, there will be a large amount of waste heat so that it can be used for processing of cashew nuts. When the factor of production costs, especially energy costs can be minimized and even eliminated altogether, the processed cashew nut products ready for consumption become increasingly competitive and profitable. The use of cashew shells for the production of CNSL and charcoal briquettes in addition to economic added value also makes the zero waste cashew nut processing industry.
