Producing biochars from durian peel

Agricultural waste recycling brings benefits to businesses and the environment as well. Resa Energy Joint Stock Company (Vinh Thanh Commune, Nha Trang City) has successfully conducted a durian shell biochar production trial.

Biochars are organic materials, including soft plant tissue, woody materials, and manures that has been carbonized under high temperatures. This process releases bio-oils plus gases and leaves a solid residue which is termed biochar. Biochar is also known as a soil additive with various effects, including improving plant health through neutralizing acidity, providing improved water and nutrient retention and improved drainage and aeration, providing a habitat for beneficial soil microbes, according to Director Hoang Anh Dung, Biocarbon Joint Stock Company (Hanoi), which has cooperated with Vietnam Farmers' Association and the Farmers' Association of provinces and cities in development of a biochar project in Vietnam.

Biochar production system at Resa Energy Joint Stock Company.

According to Nguyen Van Xuan, Director of Resa Energy Joint Stock Company, a high volume of durian shell waste may harm the environment while biochar derived from durian biomass waste has huge potential for green and sustainable applications. Therefore, he came to the idea of producing biochars from durian shells.

He built a temporary device consisting of a kiln for fresh durian peels (50 - 100kg) and a vapor condenser. All are generated by solar energy. After a trial period, the kiln finally produced a variety of products.

When the kiln temperature reaches 150 - 190ºC, a wood vinegar solution is created. Then, the kiln continues to heat to form combustible gas. When the combustion gas is burned off, biochar is formed. One batch can yield 25 liters of wood vinegar and 15 - 20kg of biochar.  Wood vinegar has many benefits, including helping plants to grow better and stronger, and be resistant to pests and diseases. 1 liter of wood vinegar costs VND100,000 – 150,000.

Besides, biochar can be processed to produce smokeless coal known as a clean burning, compact smokeless fuel with a thermal value of 600Kcal/kg compared with 500Kcal/kg of normal fine coals.

According to Nguyen Van Xuan, this process contributes to the development of green, clean, sustainable agriculture. The company is willing to share the production model guidance with those interested in producing agricultural by-product-based biochars. Biochars bring many environmental benefits and act as a soil conditioner, improving physical, chemical, and biological properties and enhancing soil fertility.

The successful production trial conducted by Resa Energy Joint Stock Company has paved the way for recycling durian shells and other agricultural by-products. This process may help farmers to increase their income while contributing to environmental protection and soil productivity improvement, according to Nguyen Tan Thanh, Director of the Center for Application of Information and Science and Technology, Department of Science and Technology.

V.L

Translated by N.T