中国矿业大学2010届本科生毕业设计 第36页
配水井至接触池沿程损失：0.001×135=0.135m 自由跌落：0.6m
二次沉淀池集水槽堰上水头：0.30m 合计：1.035 m 二沉池池水位：5.785m
配水井到二沉池沿程损失:29.1×0.002=0.0582m 跌水位：0.1m 合计：0.1582m
配水井水位：5.9432m
曝气池集水槽堰上水头：0.30m 曝气池进水口损失：0.20m
曝气池至配水井沿程损失损失：197.7×0.0012=0.237m 曝气池跌水位：0.40m 配水井出水损失：0.20m 配水井进口损失：0.15m 合计：0.987 m
曝气池水位：6.9302m
配水井到曝气池沿程损失：0.6-0.4=0.2m 跌水位：0.1m
沉砂池配水井到配水井沿程损失：0.6-0.4=0.2m 跌水位：0.1m 沉砂池跌水位：0.2m 合计：0.8m
沉砂池水位：7.7302m 配水井沿程损失：0.6-0.4=0.2m 配水井跌水位：0.1m 总水头损失：3.6302m
（2）污泥处理部分高程计算
污泥流程为压力流：
储泥池泥位：5.1m
重力浓缩池到污泥投配井水头损失： 自由水头1.5m，则管道中心标高为：
?28??1.5?2.49??????1.17?0.2??25?1.85?2.52m
5.10-(2.52+1.5)=1.08m
场地面标高为4.8m ,则有，
重力浓缩池标高：4.80+3.00=7.80m 储泥井标高：4.80+0.30=5.10m 脱水机房标高：4.80+3.20=8.00m
中国矿业大学2010届本科生毕业设计 第37页
参考文献
[1] [2]
室外排水设计规范（GBJ14-87）
《给水排水设计手册》第1、5、8、9、10、11册
中国矿业大学2010届本科生毕业设计 第38页
[3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15]
张自杰主编.排水工程（下册）.第四版：中国建筑工业出版社，2000 崔玉川主编.城市污水厂处理设施设计计算. 北京：化学工业出版社，2003 金兆丰 余志荣主编.污水处理组合工艺及工程实例.北京：化学工业出版社，2005 城镇污水处理厂污染物排放标准（GB18918-2002） 城镇污水处理厂附属建筑和附属设备设计标准（GJ31-89） 地表水环境质量标准（GHZB1-1999）
《建筑给水排水设计手册》、《给水排水设计手册》
建筑部建标《全国市政工程投资估算指标 第四册 排水工程 HGZ47-104-2007》 蒋白懿主编. 给水排水管道设计计算与安装.化学工业出版社， 2005 李亚峰主编. 给谁排水工程专业毕业设计指南.化学工业出版社， 2003 金兆丰主编. 污水处理组合工艺及工程实例.化学工业出版社 高艳玲主编. 污水生物处理新技术.中国材料工业出版社 孙立平主编. 污水处理新工艺与设计计算实例.科学出版社
翻译
英文原文
中国矿业大学2010届本科生毕业设计 第39页
摘自《The Competition between Polyphosphate-Accumulating Organisms and
Glycogen-Accumulating Organisms: Temperature Effects and Modelling》,by Carlos Manuel born in Toluca, Mexico.
1.4. identification of PAO and GAO
Phosphorus (P) is a key nutrient that stimulates the growth of algae and other photosynthetic microorganisms such as toxic cyanobacteria (blue-green algae), and must be removed from wastewater to avoid eutrophication in aquatic water systems. The risk of adverse effects to the plant and animal communities in waterways declines as P concentrations approach background levels. Around the world, a growing awareness of the need to control P emissions, which is reflected in increasingly stringent regulations, has made P removal more widely
employed in wastewater treatment. Enhanced biological phosphorus removal (EBPR) promotes the removal of P from wastewater without the need for chemical precipitants. EBPR can be achieved through the activated sludge process by recirculating sludge through anaerobic and aerobic conditions. Usually, biological nutrient removal (BNR) refers to the combination of biological nitrogen removal and the EBPR process.
The group of microorganisms that are largely responsible for P removal are known as the polyphosphate accumulating organisms (PAOs). These organisms are able to store phosphate as intracellular polyphosphate, leading to P removal from the bulk liquid phase via PAO cell removal in the waste activated sludge. Unlike most other microorganisms, PAOs can take up carbon sources such as volatile fatty acids (VFAs) under anaerobic conditions, and store them intracellularly as carbon polymers, namely poly-β-hydroxyalkanoates (PHAs). The energy for these biotransformations is mainly generated by the cleavage of polyphosphate and release of phosphate from the cell. Reducing power is also required for PHA formation, which is produced largely through the glycolysis of internally stored glycogen.
Aerobically, PAOs are able to use their stored PHA as the energy source for biomass growth, glycogen replenishment, P uptake and polyphosphate storage. Net P removal from the wastewater is achieved through the removal of waste activated sludge containing a high polyphosphate content. While the majority of P removal from the EBPR process is often achieved through anaerobic–aerobic cycling, anaerobic–anoxic operation also allows P removal to occur, due to the ability of at least some PAOs (i.e. denitrifying PAOs or DPAOs) to use nitrate or nitrite instead of oxygen as electron acceptors and, therefore, perform P uptake and denitrification simultaneously. Maximising the fraction of P removal achieved anoxically can reduce process operational costs, due to savings in aeration as well as in the amount of carbon sources needed for denitrification. Currently, many different process configurations exist where both P and nitrogen removal are combined.
When operated successfully, the EBPR process is a relatively inexpensive and
environmentally sustainable option for P removal; however, the stability and reliability of EBPR can be a problem. It is widely known that EBPR plants may experience process upsets,
deterioration in performance and even failures, causing violations to discharge regulations. In some cases, external disturbances such as high rainfall, excessive nitrate loading to the anaerobic
中国矿业大学2010届本科生毕业设计 第40页
reactor, or nutrient limitation explains these process upsets. In other cases, microbial competition between PAOs and another group of organisms, known as the glycogen (non-polyphosphate) accumulating organisms (GAOs), has been hypothesised to be the cause of the degradation in P removal. Like PAOs, GAOs are able to proliferate under alternating anaerobic and aerobic conditions without performing anaerobic P release or aerobic P uptake, thus they do not contribute to P removal from EBPR systems. GAOs are believed to use glycogen as their primary energy source for anaerobic VFA uptake and PHA formation, while PHA is oxidised aerobically, leading to biomass growth and glycogen replenishment. Since GAOs consume VFAs without contributing to P removal, they are highly undesirable organisms in EBPR
systems. GAOs have indeed been found in numerous full-scale EBPR plants, and studies have suggested that they increase the anaerobic VFA requirements of these plants. Minimising the growth of GAOs in EBPR systems has been a widely researched topic recently, due to the opportunities that exist for increasing the cost-effectiveness of this process.
1.5. Factors affecting the PAO-GAO competition
Diverse studies have been undertaken aiming at getting a better understanding about the influence of different environmental and operating conditions on the PAO-GAO competition. The effects of temperature, types of influent carbon sources, pH and influent P/VFA ratio, among other parameters, have been observed to play an important role on the competition between PAO and GAO.
1.5.1. Temperature effects
Most of the lab-scale studies carried out to address the effects of temperature on the PAO-GAO competition agree on the statement that, at wastewater temperatures higher than 20 C, the activity of the BPR process tends to deteriorate and GAO become the dominant
microorganisms. However, the underlying mechanisms of the EBPR process deterioration and actual temperature effects on the metabolism of PAO and GAO remain unclear since all those studies were not performed using enriched PAO and GAO cultures. At full-scale systems,
different studies have described the dominance of GAO and the EBPR performance deterioration of wastewater treatment plants handling warm effluents (where sewage temperature is higher than 20 C) .These corroborate the conclusions withdrawn from lab-scale studies.
Brdjanovic et al. (1997, 1998a) carried out a systematic study on an enriched PAO culture in order to understand the short- and long-term temperature effects on the EBPR process. On the contrary, analogous systematic studies with an enriched GAO culture have not been reported yet. Since PAO and GAO compete for substrate under anaerobic conditions, the effects of temperature on their anaerobic metabolisms play a crucial role. Moreover, despite the fact that biomass production and glycogen storage take place under aerobic conditions, limited attention has been paid to the effects of temperature on the aerobic metabolism of GAO. A systematic study on an enriched GAO culture could provide important information to understand the occurrence of these microorganisms at full-scale wastewater treatment plants (WWTP). Furthermore, the anaerobic and aerobic temperature dependencies of GAO could be combined to model the interaction between PAO and GAO at different temperatures, which may furthermore