BIOCHAR AS A SUPPLEMENTARY MATERIAL FOR BIOGAS PRODUCTION

In view to numerous physical and chemical properties biochars can be used in many applications in the area of environmental protection and engineering. Recent findings show that biochar can be also applied in biogas production. Relatively high chemical stability and low susceptibility to degradation, high specific surface area, microporosity and the presence of functional groups indicate that biochar can have a potential for production of biogas. The available results from laboratory studies show that biochar can facilitate mineralization of organic matter and increase the yield of methane. Due to relatively high cost of biochar, the most favourable solution would include the following applications of biochar: (1) production of biomass for biogas production (as an additive to animal feed and bedding, a soil conditioner), (2) preparation of mixture (as an amendment), (3) inoculation of microorganisms (as an inoculum carrier), (4) treatment of biogas (as an absorbent), (5) treatment of liquid fraction of digestate (as a sorbent), (6) management of solid fraction of digestate (as a substrate for biochar production). However, the conducted studies need further work and confirmation in larger scale. Also, the effects of biochar on anaerobic fermentation dynamics should be investigated and explained