大型UASB系统磷化氢分布及磷平衡研究  

Distribution of Phosphine and Phosphorus Balance in a Full-scale UASB System

作　　者：丁丽丽[1] 朱益新[1] 梁瀚文[1] 王强[1] 莫伟恒[1] 任洪强[1] 王晓蓉[1] 

机构地区：[1]污染控制与资源化研究国家重点实验室南京大学环境学院,南京210093

出　　处：《南京大学学报（自然科学版）》2005年第6期620-626,共7页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金(50278041);江苏社会发展重点招标项目(BS2002049);江苏省环境工程重点实验室基金(KF04002)

摘　　要：重点研究厌氧UASB反应器污泥沼气中产生的气态磷化氢、结合态磷化氢沿高度分布以及磷平衡.结果表明,沼气中平均磷化氢浓度为1.94～17.92ngPH3/m3;反应器上空大气中气态磷化氢浓度约为0.09～0.16ng PH3/m3.反应器周围100m大气中未测到磷化氢.污泥结合态磷化氢浓度及沿高度分布随生产季节差异较大,4月份测得结合态磷化氢浓度较高(19.14～106.3 ngPH3/kg湿泥),沿高度呈波浪形走势;10月份浓度仅为4月份的9%～74%(9.05～27.52 ng PH3/kg湿泥),呈顶部和底部浓度高中间低的趋势,这可能与10月份污染物浓度低流量高有关.反应器顶部溢流区污泥中结合态磷化氢浓度高达100.1 ng PH3/kg湿泥(4月份).由于溢流区阳光可以直射而且与空气直接接触,这意味着很可能存在另一种磷化氢生成新机制,即不同于厌氧微生物生成磷化氢. 磷平衡研究发现,每天通过沼气损失的P量为4.5～46.6μg P,占总磷去除量的(0.434～4.25)×10-6‰.每天以污泥结合态磷化氢方式损失的磷量可估算为42.03～146.7μgP,占废水总磷去除量的(3.82～14.1)×10-6‰.排泥损失的总磷量为4.45 kg P/d,占废水总磷去除量的43%.废水通过厌氧生成磷化氢除磷可行性极低.Distribution of gaseous phosphine, matrix-bound phosphine and phosphorus balance in a full scale UASB reactor were investigated. Results showed that mean free phosphine concentration in the biogas was 1.94 - 17.92 ng PH3/m^3. Free phosphine concentration was 0.09 - 0. 16 ng PH3/m^3 in the atmosphere at the top of UASB. No phosphine was detectable in the ambient air 100 m from the UASB reactor. Distribution of matrix-bound phosphine along the height of the sludge blanket changed greatly in different seasons. In April, higher matrix-bound phosphine concentrations （19.14-106.3 ng PH3/kg wet sludge） were achieved, which followed a wavelike trend along the height of sludge blanket. In October, only 9 % -74 % of the concentrations in April were observed, which were higher both at the top and bottom of sludge blanket than those in the middle. Lower wastes content and higher up-flow rate may contribute to this change. In the overfall, as high as 100.1 ng PH3/kg wet sludge of mean matrix-bound phosphine in the sludge was found. Sunshine and sufficient air contact in the overfall indicates that a new mechanism of biological phosphine formation may exist other than anaerobic phosphate reduction. Investigation of phosphorus balance showed that 4.5 - 46.6 μg P in the biogas was released per day, which only accounted for （0. 434-4.25） × 10^-6‰ of total phosphorus removal from wastewater. 42.03 - 146.7 μg P as matrix-bound phosphine was removed along with sludge discharge, which accounted for （3.82- 14.1） × 10^-6‰ of total phosphorus removal. 4.45 kg P of total phosphorus in the discharged sludge contributed to 43 % of total phosphorus removal from wastewater. The probability of anaerobic phosphate removal by phosphine formation is little.

关 键 词：大型UASB 厌氧 磷化氢 磷平衡 

分 类 号：X701[环境科学与工程—环境工程]