我国城镇污水处理厂建设及运行现状分析

截至2009年底,全国投运的城镇污水处理设施共1 916座,总设计处理能力10 594万m3/d,平均日处理水量8 132万m3/d,设施平均利用率为76.8%。对污水处理厂设计处理规模的统计分析表明:以小型污水处理厂(5万m3/d以下)增长最为迅速;大型污水处理厂和采用氧化沟工艺的污水处理厂的平均利用率均相对较好;污水处理厂的建设以及污水处理能力存在显著的地域分布特点,除了大西北地区,其他七大区域的平均利用率均在70%以上;城镇污水处理能力与GDP具有较好的线性相关性。污水处理厂的建设应因地制宜地选择合适的主体工艺类型和设计规模,有效提高设施利用率。     

行业综合信息

陕西省留坝县污水处理工程联系单位:留坝县规划局项目内容:留坝县污水处理工程项目位于留坝县城关镇,污水处理厂设计规模近期(2010～2015)为2 000m3/d,远期(2016～2025)4 000m3/d,总投资为2 728万元,其中污水处理厂建设投资1 209万元,污水管网建设投资1 519万元。服务范围为西北起党校,东南至大滩路;服务面积2     

信息三则

福州市将建 2座污水处理厂目前福州市正在加快建设新的污水处理厂 ,计划今年建成金山污水处理厂 ,处理规模为 5万m3 /d ;今年至2 0 0 7年建成连坂污水处理厂 ,处理污水近期规模为 1 5万m3 /d ,远期规模为 4 5万m3 /d。福州市已投入 30多亿元加快城市污水处理设施建设 ,现拥有祥坂、马尾、快安、洋里 4座污水处理厂 ,日处理污水能力达 2 9万m3 ,城市生活污水处理率已接近 6 0 %。洋里污水处理厂是该市实施水环境治理的核心工程 ,远期规模为 70万m3 /d ,一期设计规模为 2 0万m3 /d ,目前实际处理规模近 1 7万m3 /d。 (水工 )东莞计划投资 2 3 …     

山西省城镇污水处理工程能耗水平与特征研究

城镇污水处理属于能量密集的综合技术,污水处理厂的高效运行在节能减排的关键时期尤为重要.采用统计分析的方法,选取单位水量电耗和单位COD去除量电耗两项指标对山西省82座城镇污水处理厂2009年的能耗状况及其影响因素开展研究,提出城镇污水处理节能建议.山西省城镇污水处理厂2009年单位水量电耗约为0.469kW·h/m3,单位COD去除量电耗为1.867kW·h/kgCOD,均高于全国平均水平,具有较大的节能潜力.研究分析了设计规模、工艺技术路线、排放标准、运行负荷率和季节变化与污水处理厂能耗水平的关系.重点挖掘中等规模污水处理厂的节能潜力和提高运行负荷率是山西省城镇污水处理厂节能降耗的关键.     

小型污水处理设施适用工艺及存在问题

介绍污水处理规模<1 000 m3/d的小型污水处理设施所适用的污水处理工艺,作为新建小型污水处理设施的工艺选择。并指出小型污水处理设施运行管理中的问题,以发挥小型污水处理设施处理污水的重要作用。     

中国城镇污水处理厂运行能耗影响因素研究

采用描述统计方法,对我国1 441座城镇污水处理厂2011年的处理工艺和处理规模等进行了统计分析。对污水处理厂进、出水浓度,污染物去除量等进行统计分析,并且对污水处理工艺类型、处理规模等显著影响能耗的因素进行了分析。探讨现阶段我国城镇污水处理厂在进出水状况、处理量、能耗等方面的总体情况。     

关注城镇污水处理厂运营困境,共同探寻破解之道

<正>随着城镇化进程的不断加速以及水污染问题的日益突出,我国城镇污水处理设施近十多年来持续高速建设。目前,全国共建成并投入运营4 000多座城镇污水处理厂,日总污水处理规模超过2亿m~3,位居世界第一,约占全球总污水处理规模的1/5。20多万名污水处理从业人员在一线日夜运营维护,大量基层执法人员动态严格监管,对保护水环     

上海安亭污水处理厂三期全地下式扩建工程思考

上海安亭污水处理厂三期扩建工程采用全地下一体化箱体建设形式,土建规模10万m3/d,设备按5万m3/d配置.污水处理采用AAO-MBR工艺,出水执行《城市污水处理厂污染物排放标准》(GB 18918-2002)一级A标准,其中NH3-N和TP执行地表Ⅳ类水标准.通过系统回顾污水处理厂的建设历程,分析总结了污水处理厂在处...     

基于冗余技术的污水处理控制系统设计

在介绍长沙市某污水处理厂生产工艺流程及控制要求的基础上,综合利用现代控制技术、网络冗余技术、现场总线技术和计算机技术对城市污水处理自动控制系统进行冗余设计。充分考虑了成本、维护可靠和先进性等因素,采用西门子公司的S7-400PLC和ET200M扩展模块实现污水处理的冗余控制,设计了污水处理厂自控系统网络以及各PLC分站的具体配置方案。实际生产表明,该系统既提高了污水处理系统的稳定性,又达到了节能降耗的目的。     

中区污水处理厂的自动控制方案

随着城市工业化的迅速发展,自动控制系统逐步应用到城镇污水处理厂监控过程中。设置适合的自动控制系统,不仅可以减少劳动强度、节省人力资源和能源消耗,还可以提高污水处理效率以及水质变化时及时调节能力。文章介绍了大庆油田供水公司中区污水处理厂的集散型控制系统的结构和功能及自动控制原则,并选择了合理的控制方案。     

Automatic control for do and pH in the activated sludge process in a coke wastewater treatment plant

The objective of this study is to develop an automatic control system for dissolved oxygen (DO) and pH of the activated sludge process in a coke wastewater treatment plant. A discrete type autotuned proportional-integral (PI) controller using an auto-regressive exogenous (ARX) model as a process model was developed to maintain the DO concentration in aerators by controlling the speed of surface aerators. Also a nonlinear pH controller using the titration curve was used to control the pH of influent wastewater. This control system was tested in a pilot scale plant. During this pilot plant experiment, there was small deviation of pH and the electric power consumption of surface aerators was reduced up to 70% with respect to the full operation when the DO set point was 2 mg/1. For real plant operation with this system, the discrete PI controller showed good tracking for set point change. The electricity saving was more than 40% of the electricity consumption when considering surface aerators. As a result of maintaining the DO constantly at the set point by the automatic control system, the fluctuation of effluent quality was decreased and overall improvement of the effluent water quality was achieved.     

APPLICATION OF A NEURAL NETWORK PREDICTOR/CONTROLLER TO DYNAMIC POSITIONING OF FLOATING STRUCTURES

ＮＯＭＥＮＣＬＡＴＵＲＥＡｊ ———ａｖｅｃｔｏｒｏｆｌｅｎｇｔｈＮｗｈｏｓｅｅｌｅｍｅｎｔｓａｒｅｒａｎｄｏｍｎｕｍｂｅｒｓ.ｂｊ ———ｒａｎｄｏｍｎｕｍｂｅｒ .ｇｍ ———ｓｑｕａｓｈｉｎｇｆｕｎｃｔｉｏｎ .Ｉｚ ———ｍａｓｓｍｏｍｅｎｔｏｆｉｎｅｒｔｉａｌａｂｏｕｔｔｈｅｚ ａｘｉｓ .Ｉ———ｔｈｅｔｏｔａｌｎｕｍｂｅｒｏｆｌａｙｅｒｓ .ＯＩｍ(ｔ)———ｔｈｅｓｉｇｎａｌｃｏｍｉｎｇｏｕｔｆｒｏｍｔｈｅｍｔｈｎｏｄｅｉｎｔｈｅｏｕｔｐｕｔｌａｙｅｒ .Ｍｉ ———ｔｈｅｎｕｍｂｅｒｏｆｎｏｄｅ…     

Knowledge-based control and case-based diagnosis based upon empirical knowledge and fuzzy logic for the SBR plant.

Because biological wastewater treatment plants (WWTPs) involve a long time-delay and various disturbances, in general, skilled operators manually control the plant based on empirical knowledge. And operators usually diagnose the plant using similar cases experienced in the past. For the effective management of the plant, system automation has to be accomplished based upon operating recipes. This paper introduces automatic control and diagnosis based upon the operator's knowledge. Fuzzy logic was employed to design this knowledge-based controller because fuzzy logic can convert the linguistic information to rules. The controller can manage the influent and external carbon in considering the loading rate. The input of the controller is not the loading rate but the dissolved oxygen (DO) lag-time, which has a strong relation to the loading rate. This approach can replace an expensive sensor, which measures the loading rate and ammonia concentration in the reactor, with a cheaper DO sensor. The proposed controller can assure optimal operation and prevent the over-feeding problem. Case-based diagnosis was achieved by the analysis of profile patterns collected from the past. A new test profile was diagnosed by comparing it with template patterns containing normal and abnormal cases. The proposed control and diagnostic system will guarantee the effective and stable operation of WWTPs.     

计算机监控系统可靠性冗余方式的设计与实施

为了提高计算机监控系统的可靠性，根据监控系统结构和形式的不同，将其系统安全性、可靠性的冗余方式归纳为电源冗余、控制器冗余、输入／输出冗余和通信冗余，以及应用软件的安全与冗余等方式。文中对龙羊峡水电厂计算机监控系统可靠性的冗余方式作了详细介绍。     

Pilot-testing an alternative on-site wastewater treatment system for small communities and its automatic control.

The pilot test of a new alternative for small wastewater treatment system has been conducted for two years. It consists of a hybrid bioreactor and the expert system including the programmable logic controller and human-machine interface. In order to monitor its status, the real-time data was transferred from the remote station to the central station via a wireless local area network. More efficient and stable performances were observed at automatic operating mode compared with the manual. On an average, COD, SS, T-N and T-P concentrations in the effluent from the hybrid bioreactor were less than 14, 7, 12 and 0.9 mg/L, respectively. According to the result from laboratory experiments, the quality of treated wastewater with chemical coagulation process followed by sand filtration was enough to be utilized again if a final disinfection step is included.     

炼油废水处理采用BAF工艺的控制系统

介绍了炼油废水采用曝气生物滤池(BAF)处理工艺的工作原理,并对工艺控制系统的特点及要求作了简要介绍,控制系统采用SIMATICS7-300可编程控制器实现炼油废水处理工艺设备的控制。具体介绍了控制系统的结构、任务分配及实现、控制方式和程序设计思路,对阀类、曝气机、鼓风机和水泵采用了顺序控制、时限控制和条件控制相结合的控制原则。     

Automatic control and remote monitoring system for biological nutrient removal on small wastewater treatment plants in Korea.

Many small-size wastewater treatment plants in Korea's rural communities are designed to remove organic and suspended matter only, and they generally show a large fluctuation in the influent loading compared to municipal wastewater treatment plants (MWWTPs). They also have no professional engineers stationed for efficient operation against mechanical breakdown. For those reasons, the wastewater treatment plants have low efficiency in treatment of nitrogen and phosphorus as well as organic matter. In order to solve those problems, this study developed an automatic control system and RMS (remote monitoring system), which can keep efficiency stable despite any change in the small plants' loading rates and are capable of removing nutrient materials such as nitrogen or phosphorus. According to the results of the Experimental SBR system of the automatic control program, complete nitrification was made under oxic conditions and denitrification occurred as NO3-N concentration decreased by 0.5 mg/l in anoxic conditions and excellent nitrogen removal efficiency was seen generally. The Experimental SBR system created "phosphate release and uptake" effectively and displayed phosphate-removing efficiency up to more than 80% as the concentration of effluent was kept low by 0.4 mg/l. RMS developed in this study transmits a plant's data and operation states to clients in remote locations in real-time interval through the Internet. Therefore, although you are in a remote location, it allows you to see if a plant is properly operated or there is any breakdown.     

New ORP/pH based control strategy for chlorination and dechlorination of wastewater: pilot scale application.

Due to its efficiency and low capital demands, chlorination has been widely used for disinfection in many wastewater treatment plants. Since the oxidation power of free chlorine is bigger than combined chlorines which are formed from the reaction between chlorine and reducing agents in water (especially, NH4+ and organic nitrogen), for effective disinfection, excess amount of chlorine is added until all the reducing agents are oxidized and free chlorine is available. After chlorination, chlorine residues in wastewater are usually reduced with SO2 or sulfites before the treated wastewater is discharged, since they are toxic to aquatic life. Addition of excess amount of SO2 or sulfite should be avoided. Otherwise, they consume dissolved oxygen in a river or stream and may have adverse impact on the aquatic life. Determination of wastewater chlorine demand and of sulfite dosages for dechlorination has been a challenge to WWTP operators, due to the dynamic characteristics of wastewater. Recently, a new ORP/pH based approach to determine chlorine demand and sulfite dosage was proposed. The method utilizes significant points occurring on the pH and ORP profiles during chlorination and dechlorination titrations. In this study, the proposed automatic titration system has been implemented into a control system to optimize chlorine and sulfite doses for a pilot scale chlorination/dechlorination system. In short, the disinfection system with the pH/ORP based controller showed very successful results; complete inactivation of total coliforms, and almost zero residual chlorines and high DO in its effluent.     

Iterative design of a nitrate controller using an external carbon source in an activated sludge process

More stringent effluent and cost requirements are increasing the need for better control of wastewater treatment plants. In an activated sludge process, the nitrogen removal efficiency may be improved by adding an external carbon source. In this paper, automatic control of the nitrate level by regulating external carbon flow is discussed. More specifically, an iterative tuning procedure for the controller is outlined. Iterative controller design schemes aim at tuning high performance controllers of low complexity using closed loop data. The basic strategy used in this paper is an iterative pole placement controller design procedure. The suggested approach is compared with conventional design in a simulation study.     

Application of remote monitoring and automatic control system using neural network for small wastewater treatment plants in Korea.

For this study, an automatic control system has been developed by using a neural network and internet-based remote monitoring system for efficient operation of plants that have a serious variance of influent loading and have difficulties in appropriate maintenance, just like small wastewater treatment plants in Korea. In the control algorithm, ORP was used as the main sensor for control. At the point where the ORP value was judged to reach the "nitrate knee" of denitrification and phosphorus release, ORP indicated the state of lower saturation read by the neural network and then changed the operating condition from the reduction state to the oxidation state. For example, if ORP indicates the state of higher saturation at the point of "nitrogen breakpoint" or "ammonia valley" of nitrification, the neural network reads it and cuts off the oxygen supply and mixing. The dORP data have been used as one of the main input for the neural network. After the operation of lab-scale cyclic aeration process using an automatic control system, it has been found that regardless of loading variance, more than 95% of organic matters and more than 60% of nitrogen and phosphorus have been removed. Assuming that an internet-connected computer and a basic web browser are available, this study has developed a remote monitoring system that can monitor the operating status of small plants or any troubles with them.