摘要
该文结合海产养殖废水的盐度效应特点,开展了浸没式膜生物反应器(membrane bioreactor,MBR)协同粉末活性炭(powder activated carbon,PAC)处理含盐废水的试验。考察了投加PAC对于MBR污染物去除性能及膜污染的影响;盐度变化过程中(0~35 g/L)MBR对化学需氧量(chemical oxygen demand,COD)、氨氮(ammonia nitrogen,NH_4^+-N)、亚硝酸盐氮(nitrite nitrogen,NO_2-N)处理效果;以及含盐废水长期作用下微生物性能、膜通量、絮体粒径的变化情况。重点分析0~5 g/L的盐度变化,本体溶液中的溶解性有机物(soluble microbile products,SMP)和污泥絮体中胞外聚合物(extracellular polymeric substances,EPS)组成及含量的变化情况。结果表明:MBR-PAC对COD的去除效率比MBR高7.3%,对NH_4^+-N、NO_2-N去除的稳定性优于MBR;两工艺条件下膜通量随盐度变化呈现类似的趋势,即敏感期衰减,稳定期得到一定程度的恢复。养殖废水长期作用下,MBR-PAC膜通量是MBR的1.5倍,MBR-PAC的污泥粒径相对于MBR增加了52μm。盐度变化过程中,PAC由于其吸附性能及絮凝能力,能吸附本体溶液中的溶解性微生物代谢产物,相对于MBR,蛋白质的含量减少了34.0%。MBR-PAC适用于海产养殖废水的处理。
With the rapid development of marine aquaculture industry, the amount of wastewater discharged is increasing and the water environment in the coastal areas is seriously deteriorated. Because of high concentration of total suspended matter; the content of soluble organic matter and inorganic matter in marine aquaculture wastewater is huge, whichresult indifficulties for treatment.In order to protect the marine environment and reduce the disease spread, the treatment of intensive aquaculture wastewater has become an inevitable trend. However, mariculture wastewater is more difficult to treat than that of freshwater, because of the effects of salinity, especially on membrane′ s microbeeinhibition and contamination mitigation. In this paper, activated sludge within membrane bioreactor（MBR） disturbed by mariculture wastewater was investigated, during and after salt shock, meanwhile, effect of powdered activated carbon（PAC）, was examined in parallel lab-scale MBR, particularly on their contaminant removal performance and membrane fouling influence, within the salinity ranging from 0 g/L to 35 g/L. Concentration of chemical oxygen demand（COD）, ammonia nitrogen（NH_4~＋-N） and nitrite nitrogen（NO_2-N） were analyzed emphaticallyunder the long-term effect of macriculture wastewater, besides,variation of microorganism properties, membrane flux, and floc particle size were studied. Particularly, salinity changes range from 0 g/L to 5 g/L were selected to analyze corresponding,composition and concentrationchanges of the dissolved organic matter in bulk solution soluble microbileproducts, SMP and sludge flocs extracellular polymers substances（extracellular polymeric substances, EPS）, which could help to explain the relationship between the hydrophobicity of sludge and polysaccharide,protein. The results showed that PAC could improve the anti-fouling ability of membrane, i.e. For MBR-PAC,The COD removal efficiencyis 7.3% higher than that of MBR,combined with better removal stability of NH_4~＋-N and NO_2-N. For MBR,the fluctuation of removal of NH＋4-N and NO2-N was more obvious. In the process of salinity changes, the membrane flux of two parallel lab-scales presented a similar trend, in detail, the flux declined in the sensitive period andrecovered to a certain extent in stationary phase. However, the recovery period of MBR-PAC system was shorter than that of MBR, the change of flux is moreobvious in MBR. In result, the membrane flux under MBR-PAC system could be improved remarkable, which showed about 1.5 times than that of MBR, in the end, the flux of MBR was lower, and the membrane of MBR could be damaged. During the salinity changing process, PAC could increase the sludge relatively hydrophobic（RH）and average floc sludge particle size, at the same time, adsorption and flocculation ability of PAC would contribute the reduction of microbial metabolites, particularly for small molecular protein,obtaininga 34% reduction. At the end of operation, the sludge mean particle size of MBR-PAC waslarger, and the value increased 52 μm than that of MBR.Conclusions could be made that introduction of PAC is a useful mitigation strategy for MBR. Slow down membrane fouling rate. MBR-PAC is suitable for mariculture wastewater treatment, and the treatment effect is superior to MBR.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2016年第6期248-253,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
浙江省科技厅公益项目(2013C33005)
浙江省海洋经济创新发展区域示范成果转化及产业化项目(2015-83)
关键词
膜生物反应器
活性污泥
盐度冲击
粉末活性炭
海产养殖废水
membranes bioreactor
activated sludge
salt shock
powder activated carbon
mariculture wastewater
