The Transformation of Phosphorus Forms during Co-Composting of Sludge and Wheat Straw
With sewage sludge (SS) as raw materials, wheat straw bran (WSB, particle size less than 0.5cm) and wheat straw section (WSS, about 3cm) as the conditioner, experiments were carried out to investigate the transformation of phosphorus forms during co-composting of sewage sludge and wheat straw in aerated static pile composting system and natural ventilation fermentation system. The results showed that, in 120 days’ composting period, with the compost maturity, the total phosphorus content of SS+WSB and SS+WSS increased from 2.27g/kg and 2.67g/kg to 6.80g/kg and 6.13g/kg, respectively. The available phosphorus content of SS+WSB and SS+WSS increased from 1.45g/kg and 1.69g/kg to 6.24g/kg and 5.26g/kg, respectively. The organic P content of SS+WSB and SS+WSS increased from 0.72g/kg and 0.83g/kg to 2.53g/kg and 2.16g/kg, respectively. As the composting process in progress, a considerable part of inorganic phosphorus was converted into organic phosphorus, the ratio of organic phosphorus and total phosphorus increased, and adding small sized straw as compost conditioner can be much contributed to the inorganic phosphorus conversion to organic phosphorus. The transformation of inorganic phosphorus forms in the composting process was analyzed by using Hedley grading method. The results showed that the content of H2O-P for SS+WSB was higher than that in SS+WSS throughout the composting process, but the content of Residual-P was reversed for the two treatments. All the forms of phosphorus (H2O-P, NaHCO3-P, NaOH-P, HCl-P and Residual-P) for the two treatments have similar tread of gradual increase during the composting process. Due to the “concentrating effect and the activation of organic acids on the inorganic phosphorus, the content of various P forms has reached a peak period at the end of the first stage and tend to be stable at the second stage. The difference between total P and organic P should be less than the total content of all kinds of inorganic P.
Cheng JIA Rong-hua LI Zeng-qiang ZHANG Jim J WANG
College of Resources and Environment, Northwest A&F University, Yangling, Shanxi, China, 712100Shand College of Resources and Environment, Northwest A&F University, Yangling, Shanxi, China, 712100 School of Plant, Environmental and Soil Sciences, Louisiana State University, 104 Sturgis Hall,Baton
国际会议
The Fifth International Conference on Waste Management and Technology(第五届固体废物管理与技术国际会议)
北京
英文
462-466
2010-11-01（万方平台首次上网日期，不代表论文的发表时间）