Jin Zhan, Ji Fangying, He Yin, Zhao Min, Xu Xuan, Zheng Xiang-Yong
College of Life and Environmental Science, Wenzhou University, Wenzhou, China.
Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing, China.
PLoS One. 2017 Oct 24;12(10):e0187007. doi: 10.1371/journal.pone.0187007. eCollection 2017.
There are two biological systems available for removing phosphorus from waste water, conventional phosphorus removal (CPR) and denitrifying phosphorus removal (DPR) systems, and each is characterized by the type of sludge used in the process. In this study, we compared the characteristics associated with the efficiency of carbon utilization between CPR and DPR sludge using acetate as a carbon source. For DPR sludge, the heat emitted during the phosphorus release and phosphorus uptake processes were 45.79 kJ/mol e- and 84.09 kJ/mol e-, respectively. These values were about 2 fold higher than the corresponding values obtained for CPR sludge, suggesting that much of the energy obtained from the carbon source was emitted as heat. Further study revealed a smaller microbial mass within the DPR sludge compared to CPR sludge, as shown by a lower sludge yield coefficient (0.05 gVSS/g COD versus 0.36 gVSS/g COD), a result that was due to the lower energy capturing efficiency of DPR sludge according to bioenergetic analysis. Although the efficiency of anoxic phosphorus removal was only 39% the efficiency of aerobic phosphorus removal, the consumption of carbon by DPR sludge was reduced by 27.8% compared to CPR sludge through the coupling of denitrification with dephosphatation.
有两种用于从废水中除磷的生物系统，即传统除磷（CPR）系统和反硝化除磷（DPR）系统，每种系统的特点在于该过程中使用的污泥类型。在本研究中，我们以乙酸盐作为碳源，比较了CPR污泥和DPR污泥中与碳利用效率相关的特性。对于DPR污泥，在释磷和吸磷过程中释放的热量分别为45.79 kJ/mol e-和84.09 kJ/mol e-。这些值比CPR污泥相应的值高出约2倍，这表明从碳源获得的大部分能量以热量形式释放。进一步研究表明，与CPR污泥相比，DPR污泥中的微生物量较少，污泥产率系数较低（分别为0.05 gVSS/g COD和0.36 gVSS/g COD），生物能分析结果表明这是由于DPR污泥的能量捕获效率较低所致。尽管缺氧除磷效率仅为好氧除磷效率的39%，但通过反硝化与脱磷的耦合，DPR污泥的碳消耗量比CPR污泥减少了27.8%。
