Nitrogen transformations during co-composting of herbal residues,spent mushrooms,and sludge
Nitrogen transformations during co-composting of herbal residues,spent mushrooms,and sludge作者机构:Department of Environmental Engineering Zhejiang University Hangzhou 310029 China Department of Environmental Sciences COMSA TS University Abbottabad 22010 Pakistan
出 版 物:《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 (浙江大学学报(英文版)B辑(生物医学与生物技术))
年 卷 期:2010年第11卷第7期
页 面:497-505页
核心收录:
学科分类:083002[工学-环境工程] 0830[工学-环境科学与工程(可授工学、理学、农学学位)] 08[工学]
主 题:Sewage sludge Spent mushrooms Herb residues Maturity Nitrogen retention Co-compost
摘 要:Sewage sludge composting is an important environmental measure. The reduction of nitrogen loss is a critical aim of compost maturation, and the addition of spent mushrooms (SMs) and herbal residues (HRs) may be helpful. To evaluate the nitrogen transformations during co-composting of sewage sludge, SMs, and HRs, windrows were constructed in a residual processing plant. Dewatered sewage sludge and sawdust were mixed with SMs and HRs at two proportions on a fresh weight basis, 3:1:1 (sewage sludge:sawdust:SMs or HRs) and 3:1:2 (sewage sludge:sawdust:SMs or HRs). The mixture was then composted for 40 d. Changes in the physicochemical charac- teristic of sewage sludge during composting were recorded and analyzed. Addition of SMs and HRs accelerated the temperature rise, mediating a quicker composting maturation time compared to control. The addition also resulted in lower nitrogen losses and higher nitrate nitrogen levels in the compost products. Among the windrows, SM and HR addition improved the nitrogen status. The total nitrogen (TN) and nitrogen losses for SM and HR treatments ranged from 22.45 to 24.99 g/kg and from 10.2% to 22.4% over the control values (18.66-21.57 g/kg and 40.5%-64.2%, respectively). The pile with the highest proportion of SMs (3:1:2 (sewage sludge:sawdust:SMs)) had the highest TN level and the lowest nitrogen loss. The germination index (GI) values for all samples at maturity were above 80%, demonstrating optimal maturity. The addition of SMs and HRs augments sewage composting.