Biowaste From Rice Straw And Biochar Production Potential From Viet Nam

In recent years,environmental problems in agricultural production,especially how to reduce greenhouse gas emissions have aroused wide concerns around the world.Vietnam is one of the countries that are mostly affected by climate change in the world.In order to respond to global climate change and reduce greenhouse effect,Vietnamese Government have signed a series of policies and measures to ensure food safty.promote green economy,decrease carbon emission rate and increase greenhouse gas sequestration,thus improving the ability of dealing with climate change at a global scale.Vietnam is an agricultural country,and the total quantity of straw constantly increases in the development of agriculture.While the degree of straw utilization and industrialization is low,the problem of environmental pollution becomes serious day by day due to burning of straw.In recent 10 years,the application of high temperature pyrolysis and carbonization of organic biomass has been an innovation of straw recycling in agriculture production.In this paper,we studied the situation and problem of agriculturalwastes utilization in Quang Ninh Province,and came up with approaches and measures for using rice straw biochar based on data collection and literature search.Furthermore,biochar's economic,environmental and social benefits were analyzed and assessed in order to offer a theoretical basis for straw fertilizer utilization in Quang Ninh Province.The main results are as follows:(1)Annual output and utilization of agricultural wastes in Quang Ninh Province were initiatively assessed based on the data of agriculture production and development.The total output of agricultural wastes was 0.34million ton per year,of which the rate of rice waste was 0.22 million ton per year,with 52.46%of total crop waste.In addition,there are still many different crop wastes which could be used as raw materials to produce biochar.(2)There were many ways of utilizing crop wastes in Quang Ninh each year,i.e.cooking,feeding animals,returning to field,compost making,basic stock of edible fungi,etc.However,about 42%of rice straw was burned in fields,which are serious resource wastage and environmental pollution.(3)The scheme of using crop straw and wastes to produce biochar and applying in soil as fertilizer was suitable recomnendation of farmland carbon sequestration and greenhouse gas reduction,and was suitable for the agricultural production in Quang Ninh rural area.Specially,in hilly and mountainous areas,the rice straw biochar can be used as fertilizer to improve soil fertility and increase crop yield.(4)In the production schemes of biochar's net present value were gained though the estimation of cost-benefit analysis.These were 1.06,4.96,7.96 and 1.83 million Vietnamese dong(1RMB=3400VND)per hectare per year for scheme one,scheme two,scheme three and carbon exchange benefit,respectively.Producing biochar could therefore be a sound way to increase farmers' income.Biochar has not only economic value,but also huge environmental and social value.Effective use of rice straw as materials to produce biochar would bring economic value to farmers for its low cost,bring social value to society for its job creation,and bring environmental value for its role in greenhouse gas reduction.