On 28 August 2014, Phonh organized a small workshop in HEPA to share about making Biochar with rice husk. The workshop consisted of 2 parts: a short discussion on the basics of biochar and the experience with charcoal and biochar in HEPA and other communities, and after that the practice of making biochar from rice husk.
 
Biochar is a type of charcoal that can be used to improve the soil, especially when combined with manure, compost or other organic materials to feed the soil. There are many ways and materials to make and apply it; some traditional and others combining traditional methods with new techniques. Earlier, HEPA has experimented with making biochar from wood and bamboo in a so-called ‘TLUD’ stove designed by David Bauer (former volunteer, see also: http://ffs.org.vn/detail/Quy-trinh-che-tao-than-sinh-hoc-cung-cap-nang-luong-cho-dat-362.html). The method introduced by Phonh uses rice husk and is very easy to use. During his FK internship, Phonh has learned this technique at the ISAC organisation in Chiang Mai, Thailand, together with other farmers and students from the Chiang Mai University.

The biochar is made by making a kind of small oven with small holes in the surface and with a big pipe on the top to let the smoke out. First, the oven is filled with straw or paper and set on fire, and after that the oven is covered in a pile of rice husk so only the pipe protrudes. The oven heats the pile from inside and burns the rice husk slowly. The husk should not catch fire, because then it will burn to ashes, so when it gets too hot and flames appear on the outside, the husk should be turned over to cover the flames. After 4 – 5 hours, while continuously controlling the heat and the fire in the pile, almost all of the husk inside the pile has become black. The pile can now be spread out and cooled down by pouring water over it. After that it can be mixed with the soil in garden beds.
 
All participants agreed that this method to make biochar is very easy, cheap and convenient. The oven can be made from recycled materials and it is especially practical in rural communities where rice husk is easily available. In HEPA, there usually is no rice husk available so students and staff will continue to experiment with different techniques and local materials to see which method is most suitable.
 
A detailed curriculum document about Biochar will be posted on this website soon.

Written by: Miriam van Muijlwijk