生物炭和过磷酸钙投加对鸡粪-烟末-菌糠联合堆肥腐熟度及含氮气体排放的影响

Effects of Biochar and Superphosphate on Maturity and Nitrogenous Gas Emission During Co-composting of Chicken Manure and Tobacco Wastes with Spent Mushroom Substrate as the Bulking Agent

鸡粪-烟末-菌糠(CK)联合堆肥过程中存在升温慢、水分去除难、极易排放污染气体和腐熟周期长等问题。本研究以鸡粪、烟末和菌糠为原料,通过添加外源固氮材料来减少鸡粪-烟末-菌糠联合堆肥过程中含氮气体(NH3和N2O)的产生及改善堆肥腐熟度,设置了添加5%(质量分数)过磷酸钙、添加10%生物炭的堆肥试验。结果表明,处理堆体温度均能在55℃持续8 d以上,达无害化标准。与CK处理相比,添加5%过磷酸钙和10%生物炭处理堆肥腐熟度得到有效改善,但添加5%过磷酸钙处理有增加堆肥产品EC的风险;添加5%过磷酸钙处理堆肥过程中以NH3-N、N2O-N形式损失TN分别降低了32.13%和12.20%;添加10%生物炭处理以NH3-N、N2O-N形式损失TN分别降低了28.83%和34.15%。综合堆肥腐熟度、氮损失及污染气体减控效果来看,添加质量比5%过磷酸钙更有利于鸡粪-烟末-菌糠联合堆肥。

There exist several issues in composting of chicken manure,tobacco wastes,and spent mushroom substrate,including slow temperature increase,low moisture reduction,gaseous emission,and long maturation period.Thus,this study aimed to address gaseous emission(e.g.ammonia(NH3)and nitrous oxide(N2O))and increase product maturity in the composting of chicken manure and tobacco wastes with spent mushroom substrate as the bulking agent by adding nitrogen-conservation materials,which were 5%superphosphate and 10%biochar(based on wet mass of raw composting feedstocks).Results show that the temperature of all treatments could be maintained at 55℃for more than 8 days to conform non-hazardous and sanitation standards.Compared with the control treatment,adding superphosphate and biochar could improve the compost maturity,while superphosphate increased the product salinity.Total nitrogen(TN)loss in the form of NH3 and N2O was reduced by 32.13%and 12.20%,respectively when 5%superphosphate was added.By contrast,such reduction was 28.83%and 34.15%with the addition of 10%biochar.Compared with biochar,superphosphate could be more effective to reduce nitrogenous gas emission and improve compost maturity during the composting of chicken manure,tobacco wastes,and spent mushroom substrate.