translated and edited by Daisy Yu
On May 5th, China's MoA ( Ministry of Agriculture) released a pubic media policy report on announcing a list of Top 10 models of straw utilization for extension. Among these, a viable system of biochar production from crop straw and use for biochar-based compound fertilizer manufacture was newly approved and listed for commercialization. This mode was firstly practiced in a Straw Company of Qinfeng located in Liuhe District, Northern Suburb of Nanjing, developed by the Biochar and Green Agriculture center led by Professor Genxing Pan at Nanjing Agricultural University and had been tested for a viable production system with a rotatory kiln system to produce high quality biochar which is utilized for biochar compound fertilizer, in a project funded by Nanjing Municipal government since 2013. With this mode, straw carbonization is linked to, on one hand, conversion of organic matter into stable and porous biochar; and to, on other hand, to recycling bioenergy from the syngas for blending mineral nutrients in biochar fertilizer manufacture. In this way, burning as CO2 release from straw OM was avoided and biochar obtained was back to soil for soil improvement and nutrient carrier, increasing soil organic matter yearly as fertilization repeated year by year. Since April 2015, biochar fertilizer had been tested in hundreds acres of farmlands in agricultural area in Yeshan Township, Liuhe District, Nanjing, with obvious effect of improving soil fertility. For field farming, this technology could have benefits of “double savings and double gains”, that is, reduction both of chemical nutrient use and of greenhouse gas emission from agriculture, and increase both in crop yield and economic efficiency, working in a philosophy of turning black into green in agriculture. A number of relevant scientific papers published and policy reports as well as over 9 China patents registered, with this mode of straw technology.
This mode, with value-added straw recycling, has been under commercialization since 2015, but recently fast developed with the biomass recycling enterprises under Beijing Sanju Novel Materials for Environmental Protection Co, Ltd, widely in Northern China(Diagram 1). Both the rotatory kiln based production system and the formulas of biochar fertilizers as well as biochar soil conditioner have been optimized with the new projects (Diagram 2). The ambitious plan of the cooperative enterprises on straw biomass and biochar technology is to upscale up to 5M tones of straw recycled per year and 100 enterprises converting biomass to biochars, reaching a total market value of 10 billion CNY (Chinese yuan) by 2020. With this mode so far, up to 100,000 tons straws were carbonized while some twenty thousand tons straw biomass biochar fertilizer produced with additional 20 thousands tons biochar sold, giving a reduction of GHGs over 0.6 Tg CO2 equivalent. The biochar projects with straw collection and resource recycling have been also linked to poverty reduction projects in remote rural areas from northern China (Diagram3), greatly appreciated by the central government when the top leaders had an access to the novel technical exhibition held in Beijing, December 2016.
This mode has been also a part of training activities related to agricultural waste treatment and green production of China, including key note lectures given by Prof. Pan and the team. Among these, the keynote speeches were provided in the Working meeting of Rural Energy and Environment Construction (MoA, 2016); A National Training Course on Bioenergy and Environment (MoA,2016), The Green Forum, Jiangxi Provincial Government 2016 as well as 4 technical training sessions with Beijing Sanju company. It is anticipated, straw carbonization would be rapidly developing to form a novel industry of co-production of bio-material-bioenergy and bio-fertilizer in a short future.
Diagram 2 Commercial products of biochar compound fertilizer for cereals and vegetables, biochar soil conditioner and wheat straw biochar and the 2nd generation of biochar compound fertilizer (from left to right):
Courtesy to: Center of Biomass and Biochar Green Technology, Nanjing Agricultural University, and The Asian Center, International Biochar Initiative. Diagrams via Genxing Pan.
For the Chinese MoA's original anncouncement (in Chinese), click: http://www.moa.gov.cn/govpublic/KJJYS/201705/t20170503_5593248.htm