Study On The Preparation Of Caragana Biomass Carbon And Carbon Based Fertilizer

China is a large agricultural country.In order to increase grain output,a large number of chemical fertilizers are used,but the variety,application method and application amount of chemical fertilizers are unreasonable,which lead to many problems in China due to excessive use of chemical fertilizers,such as low utilization rate of chemical fertilizers,soil hardening,harmful substances in water resources and air,etc.In order to improve the current problems caused by the use of chemical fertilizers,China’s Ministry of agriculture proposes the action plan of zero growth of fertilizer use by 2020 [1].At the same time,China will produce a lot of organic emissions every year,which will cause harm to our environment.According to previous studies,biochar can be made from these organic wastes.As a kind of material with easy access and good performance,biochar can not only solve the problem of environmental pollution caused by organic wastes,but also solve the problem of chemical fertilizer use in China.Although biochar has good performance and can be used in farmland to improve yield and soil structure,there are still some shortcomings in it,such as the quantity of N element and mineral element is less,the quality is light and the transportation is difficult.In order to make up for this defect and combine it with chemical fertilizer,it will undoubtedly provide a new goal for the expansion of new varieties of fertilizer.In this paper,Caragana was chosen as the raw material of carbonization,and the carbonization temperature was 300 ℃,400 ℃,500 ℃ and 600 ℃,and Caragana carbon was manufactured at this cracking temperature.The carbonization temperature of Caragana carbon was optimized by studying the properties of the prepared Caragana carbon;The carbon based slow-release fertilizer of Caragana Caragana was prepared by mixing it with urea and bentonite in different proportion,and its p H value and element content were measured.The slow-release effect of the carbon based slow-release fertilizer of Caragana Caragana was analyzed and evaluated to optimize the production process of the carbon based slow-release fertilizer.The main results are as follows:(1)Caragana carbon has many advantages,such as a large number of C elements,ash,H / C,specific surface area,pore volume,functional groups and so on.The adsorption performance of Caragana carbon is in proportion to the carbonization temperature,and the adsorption performance increases with the carbonization temperature.In the Caragana carbon manufactured at 300 ℃-600 ℃,the difference between500 ℃ carbon and 600 ℃ carbon in specific surface area and total pore volume is not significant,and when the carbonization temperature is 500 ℃,the biomass material is basically carbonized,so considering the economic cost,resource protection and other aspects,BC500 is selected as the carrier of Caragana carbon based fertilizer.(2)Different proportion of biochar was selected as the loading material of fertilizer,and then it was added to urea respectively.The carbon based slow-release fertilizer of Caragana korshinskii was prepared by the mixed granulation method.After the research on the properties of the carbon based fertilizer,it was found that the amount of biochar had a great impact on the properties of carbon based fertilizer.The p H value,loading capacity and slow-release effect of carbon based fertilizer were positively correlated with the amount of biochar added.Among them,the carbon based slow-release fertilizer with 50% biochar is the best in loading urea and slow-release effect.(3)The comprehensive analysis shows that the C content,specific surface area and pore volume of Caragana carbon prepared by muffle furnace at 300 ℃-600 ℃ are gradually increasing.Among them,BC500 has larger specific surface area and better adsorption performance;5%,20%,35%,50%,65%Caragana carbon,95%,80%,65%,50%,35% urea and a certain amount of bentonite were respectively mixed and granulated to prepare Caragana carbon based slow-release fertilizer.With the increase of the amount of biochar added,the ratio of C \ n to Caragana carbon decreased,and the absorption and slowrelease effect of Caragana carbon on urea increased.Finally,considering the cost and environment of production,the Caragana carbon produced at the pyrolysis temperature of 500 ℃ and the pyrolysis time of1 H has a better slow-release effect according to 50% biochar addition,50% urea and a certain amount of bentonite.