Abstract:

The comprehensive utilization of straw resources is an important issue in China during the agricultural production process, while returning straw to field after carbonization is one of the important ways to achieve comprehensive utilization of straw. Biochar, as a multifunctional carbon material, has a porous carbon framework structure, abundant oxygen-containing functional groups and inorganic minerals, as well as a large specific surface area and stability. Application of straw derived biochar to the field is beneficial for improving soil physical and chemical properties, enhancing soil fertility, promoting soil carbon sequestration, greenhouse gases mitigation, and pollutant stabilization. Creating a complete standardization system is conducive to the standardization and industrialization development of biochar. However, there have been no reports on the standardization production, testing methods and application of biochar. This review summarizes the research and agricultural application background of straw carbonization and application, and summarizes the existing standards and standardized development status in the fields of straw carbonization and their returning to the field, especially in China. The results indicate that China has initially formed a standardized system based on equipment for biomass carbonization processes, biochar product quality testing, and agricultural applications. However, the standardization system for the application of straw carbonization in agriculture is not yet perfect, and the quality of existing standards is also uneven. Suggestions were put forward to strengthen the research and development of new equipment for biomass carbonization, products and standard substances, testing methods, agricultural application technology specifications, and establish systematic standards.

Key words: straw carbonization, biochar, agricultural biomass waste, comprehensive utilization of straw, soil improvement