为了解不同农业有机废弃物的资源化利用潜力,以贵州当地的玉米秸秆、烤烟秸秆、水稻秸秆、锯木屑、玉米芯粉、中药渣、猪粪、牛粪、鸡粪为对象,研究其堆肥发酵后和高温炭化后的理化特性,并进行安全性利用评价,分析其基质化、肥料化和热解生物炭化的利用潜力。结果表明,堆肥后的有机废弃物容重为0.24~0.38 g/cm3;有机碳含量为37.67%~55.94%;中药渣、猪粪、牛粪和鸡粪的电导率(EC值)较泥炭高47.62%~190.48%;玉米秸秆、水稻秸秆、玉米芯粉和牛粪培养的黑麦草种子发芽指数为0.81~0.98,接近于泥炭;除玉米芯粉外,其他有机废弃物重金属综合污染指数均低于0.7。各有机废弃物低氧高温热解后的生物炭有机碳含量为30.52%~48.98%、pH值为8.75~11.56、比表面积为13.36~102.16 m2/g。综上,堆肥后有机废弃物具有良好的通气结构、持水性能和丰富的矿质营养,通过科学配比,具有成为优质栽培基质和有机肥原料的潜力;低氧高温热解后的生物炭养分丰富,比表面积较大,具有成为土壤改良剂、重金属钝化剂和有机肥辅料的潜力。
In order to understand the potential of resources utilization of different agricultural organic wastes,taking Guizhou local corn straw,flue-cured tobacco straw,rice straw,sawdust,corncob powder,traditional Chinese medicine residue,pig manure,cattle manure,chicken manure as the research objectives,the physicochemical properties and safety utilization evaluation of the decomposed and high-temperature carbonized agricultural organic wastes were studied,and the utilization potential of matrization,fertilization and pyrolysis biochar was analyzed.The results showed that,after decomposted,the bulk density of each organic material was 0.24—0.38 g/cm3.The content of organic carbon was 37.67%—55.94%.The conductivities(EC values) of Chinese medicine residue,pig manure,cow manure and chicken manure were47.62%—190.48% higher than that of peat.The germination index of ryegrass using decomposed corn straw,rice straw,corncob powder and cow manure was between 0.81 and 0.98,which was close to peat.Except corncob powder,the comprehensive pollution index of heavy metals in other organic materials was lower than 0.7.After pyrolysis under low oxygen and high temperature,the organic carbon content of biochar was 30.52%—48.98%,the pH value was 8.75—11.56,and the specific surface area was 13.36—102.16 m2/g.In conclusion, after decomposted, organic materials have good aeration structure, water holding capacity and abundant mineral nutrition. Through scientific proportioning,they have the potential to become high-quality cultivation matrix and organic fertilizer raw materials. Biochar after low oxygen and high temperature pyrolysis has rich nutrients and large specific surface area,which has the potential to become soil improver,heavy metal passivator and organic fertilizer auxiliary materials.