Papers by Author: Wei Wei Cao

Abstract: This study used plate count method to analyze the composition of the Spore-forming bacteria community in the soil in swamping wetland, alkaline land, and desert belt, all of which grow in the upstream, midstream and downstream of swamping wetland of Wuliangsuhai. In this process, the Shannon-Wiener index, Simpson index were used to analyze the index of diversity (H), the index of evenness (J), the index of richness (R) and the index of dominance (D) of the Spore-forming bacteria community. The results showed that: the diversity index of in soil of the swamping wetland and desert belt was the highest in the midstream, second in the upstream, and lowest in the downstream; that in soil of the alkaline land was the highest in the midstream, second in the downstream and lowest in the upstream, and showed significant differences between in the midstream and downstream and in upstream; that in soil of the desert belt showed significant differences between in the upstream and downstream and in midstream; in the same area, in the desert belt soil of Spore-forming bacteria more than swamping wetland and alkaline land.

Abstract: Coking wastewater contains high concentration of refractory and toxic compounds. The effluent quality usually cannot meet the discharge limits after single conventional biological treatment processes. In order to find more effective coking wastewater treatment process, a serious hybrid treatment process were reviewed in this paper, which include: anoxic-anaerobic-oxic(A2/O) combined with membrane bioreactor (MBR); Fe/C micro electrolysis combined with Fenton process. Fenton oxidation combined with biologically process. Wastewater quality and operating parameters were compared. Through this review, we found that hybrid process is more efficiency to treat coking wastewater.

Abstract: Due to the presence of complicated and considerable amounts of toxic compounds such as phenolic compounds, thiocyanate and ammonium, coal gasification wastewater (CGW) would cause a serious environmental problem. Conventional treatment of CGW includes a series of biological treatment (mostly anoxic-aerobic process and activated sludge process) after a physico-chemical pretreatment to reduce the concentrations of phenols and ammonium. Although quite effective, these processes are still not enough to meet the strict requirements of the National Discharge Standard of China. To find more efficient way to treat CGW, a serious of hybrid processes were reviewed in this study. Through this review we found that A²O combined with MBR (anaerobic-anoxic-aerobic membrane reactor) can effectively remove COD, total organic carbon, NH₄⁺ -N, total phenols and total nitrogen (TN).