Pyrolysis and biochar potential using crop residues and agricultural wastes in China

This preliminary study examines the feasibility and applications of pyrolysis and biochar in China to understand issues about bioenergy generation, agricultural cost savings and enhancement of atmospheric quality. Multiple agricultural and animal wastes are analyzed and quantitative measures of economic and environmental benefits are provided. The Poyang Lake, one of the most important clean water lakes in China, is examined to see how pyrolysis and biochar applications can be beneficiary to farmers and society in terms of the economic and greenhouse gas values. Rice straw, corn stover, poplar, orchard wastes, animal wastes and open pasture wastes are primary feedstocks for fast and slow pyrolysis. The results show that both fast and slow pyrolysis are profitable under current situations where corn stover-based pyrolysis yields the highest economic benefits but that of animal wastes-based can offset more GHG emissions. Rice straw yields a loss but it can still be a potential choice since the material is the most popular in study area. Sensitivity analysis is provided to understand the changes of economic and environmental benefits under various market conditions and the results indicate that in general, significant profits of pyrolysis and biochar application bring additional margin of safety and therefore, pyrolysis and biochar does not incur a loss unless input costs increase more than 53% to 64%.