慈溪东部污水处理厂化学除磷工艺模拟与实时控制

阐述了化学除磷机理的新发展,对慈溪东部污水处理厂的高效沉淀池进行了化学除磷工艺模拟.建立了基于磷酸盐在线分析仪和加药泵、控制器的智能化管理控制平台,实现了化学除磷的精确加药,降低了药剂消耗量,提高了污水处理厂运行效率.     

UNITANK系统生物——化学联合除磷工艺中试研究

以诸暨市水样进行的中试研究表明,采用生物—化学联合除磷工艺对UNITANK系统进行常规改进得不偿失。但可以考虑采用生物—化学联合除磷工艺作为UNITANK系统应对TP冲击负荷的应急处理工艺。     

化学除磷的设计计算

主要介绍了化学除磷的基本原理、采用的化学药剂类型、工艺形式、投药量的计算等     

广州市大坦沙污水处理厂污泥处理过程中磷的释放及去除研究

通过分析厂区污泥浓缩池上清液、脱水机滤液、回流泵房集水井磷浓度,探讨污泥处理过程中磷的释放规律,对污泥处理过程中磷的二次释放问题进行了评价,并研究了不同化学药剂的除磷效果,比选出了合适的化学药剂及相应的最佳投药量。研究结果表明,短期内污泥处理与处置过程中磷的二次释放对进水水质的影响还未显现,今后仍需加强对系统磷负荷的监控。硫酸铝是最佳的化学化学除磷药剂。     

PO_4~(3-)-P在线测定在生物、化学联合除磷控制中的应用

介绍了PO3- 4-P连续在线检测技术及其在污水处理厂生物、化学除磷工艺中的应用情况。     

化学除油法在济钢中厚板高压除磷水中的应用

化学除油器除油法是以投加化学药剂,经混合反应使水中的油类、氧化铁皮等悬浮物通过絮凝、凝聚作用去除.济钢中厚板高压除磷水系统采用化学除油法将浊水中的乳化油、悬浮物进行处理,使出水含油量≤5 mg/L,SS≤10 mg/L,提高了出水水质和产品质量.     

污水中生物除磷技术的应用进展

阐述了化学除磷的原理和传统的生物除磷原理,重点介绍了倒置A2/O工艺、DEPHANOX工艺、BCFS工艺、A2NSBR工艺等几种经济、高效的生物除磷新技术的原理和特点,并展望了除磷技术的发展方向。     

改良A2/O工艺强化除磷控制措施研究与应用

结合南方某污水处理厂实际运行情况,对改良A2/O工艺在低碳高磷进水条件下的除磷效果进行深入研究.研究表明,通过对工艺参数的优化控制并辅以化学除磷措施,进水总磷在3～8mg/L时,出水均可达<城镇污水处理厂污染物排放标准>(GB 18918-2002)一级B标准.     

太湖流域城镇污水处理厂与排水管网优化技术研究与示范

针对太湖流域城镇污水处理厂所面临的水质提标改造、排水管网运行管理急需优化等重大问题,结合河网地区城镇污水处理厂与排水管网的运行过程与特征,对污水处理厂脱氮除磷工艺的优化运行与排水管网的运行管理进行研究,并进行技术的集成与示范.主要成果包括:提出了适合太湖流域污水处理厂提标改造的优化运行方案;建立生物处理系统的协同化学除磷控制技术示范;建立管网系统GIS数据库和优化调度决策支持系统的示范;以及相关的中试研究与设备开发.     

城市污水处理厂化学除磷效果及运行成本研究

通过对硫酸亚铁、氯化铁、硫酸铝、聚氯化铝和聚氯化铝铁的小试研究,以及时北京城市排水集团下属三座污水处理厂在沉砂池、曝气池的生产性试验研究,详细论述了化学除磷的除磷效果与化学药剂投加量、运行成本和磷削减成本的关系,用于指导和控制城市污水处理厂除磷的直接成本,并保证城市污水处理厂高效、稳定的处理效果。试验表明,当出水总磷要求小于1 mg/L和0.5 mg/L时,药剂中金属元素与去除磷元素的物质的量之比(Me/P)、运行成本、磷削减成本分别为:2～2.5、0.1～0.13元/m~3、4.5万～5.5万元/t和3～6、0.13～0.2元/m~3、5万～15万元/t。     

Application of vibration milling for advanced wastewater treatment and excess sludge reduction

As a new sludge reduction technology with a phosphorus removal mechanism, a vibration milling technology that uses iron balls have been applied to the wastewater treatment process. Three anaerobic-aerobic cyclic activated sludge processes: one without sludge disintegration; one disintegrated sludge by ozonation; and the other disintegrated sludge with the vibrating ball mill were compared. Ozonation achieved the best sludge reduction performance, but milling had the best phosphorus removal. This is because iron was mixed into the wastewater treatment tank due to abrasion of the iron balls, leading to settling of iron phosphates. Thus, the simple means of using iron balls as the medium in a vibrating ball mill can achieve both a sludge reduction of half and excellent phosphorus removal. Material balances in the processes were calculated and it was found that carbon components in disintegrated sludge were more resistant to biological treatment than nitrogen.     

粉煤灰在我国废水处理领域的利用研究

介绍了粉煤灰处理废水的物理化学特性,指出利用粉煤灰作为废水处理中的吸附剂或混凝剂,可取得良好的处理效果,并以印染、造纸、焦化、含重金属、含氟、含磷等废水处理为例,对粉煤灰在我国废水处理领域的最新应用研究作了综述。     

铁碳微电解—A/O组合工艺处理精细化工废水

嘉兴某精细化工厂采用铁碳微电解—A/O组合工艺处理生产废水.运行结果表明,出水水质稳定,COD去除率可达79.12％,出水可稳定达到《污水综合排放标准》(GB 8978-1996)三级排放标准,工艺处理成本为1.1元/m3.该工艺具有处理效果好、耐冲击负荷能力强、经济效益高等特点,在精细化工废水的处理中具有很好的应用价值.     

Economic and environmental optimization of phosphorus removal.

Do operating costs conform to environmental impact after introduction of charges on discharge of wastewater? A study on optimization of phosphorus removal at two Danish wastewater removal plants shows that this is actually the case. By measurement of inlet and outlet concentrations and of chemicals added it was possible to determine the relationships between chemical dosing and phosphorus discharge and thus calculate the operational cost and environmental impact of different dosing/discharge levels.     

Performance evaluation of physicochemical processes for biologically pre-treated livestock wastewater.

The use of a combination of biological and physicochemical methods is a promising technique to reduce highly concentrated pollutants in livestock wastewater: firstly, biodegradable organic matters, nitrogen and a part of phosphorus should be removed in a biological treatment process and then residual non-biodegradable organic matters, color and phosphorus be eliminated by physicochemical methods. In this study, therefore, the integrations of chemical coagulation, activated carbon adsorption, Fenton oxidation and ozonation were evaluated to provide an appropriate post-treatment process for biologically pre-treated livestock wastewater. With applying a single method such as coagulation and Fenton oxidation, a yellowish brown color and COD still remained. According to the experimental result, the quality of treated wastewater including color was enough to be discharged after chemical coagulation followed by ozonation or Fenton oxidation process. Among these, ozonation was the most effective technology for decolorization. Neither simple biological nor physicochemical process provides an adequate treatability for the sufficient depletion of organics and decolorization when treating livestock wastewater. Considering only the removal efficiency, the integration of Fenton oxidation and ozonation would be an efficient alternative as a post-treatment.     

改性粉煤灰处理含磷生活污水试验

为了防止水体富营养化和有效处理生活污水,以改性粉煤灰为吸附剂,对含磷生活污水进行吸附脱磷试验,并研究粉煤灰粒径、投加量、pH值、温度、振荡强度以及吸附时间等因素对脱磷效果的影响。结果表明:在粉煤灰粒径为160~200目、投加量为25 g/L、溶液pH值为3.5、水温为50℃的条件下,对磷质量浓度为6.8 mg/L的生活污水,以140 r/min的强度振荡吸附150 min,磷的去除率可高达95.3%,水样中的磷质量浓度降至0.5 mg/L以下。     

Chemical phosphorus removal to extremely low levels: experience of two plants in the Washington, DC area.

Chemical phosphorus removal using metal (iron and aluminium) salts is frequently used to control effluent soluble phosphorus levels in wastewater treatment plants. In the Washington DC area effluent phosphorus requirements are extremely stringent to protect the Chesapeake Bay. Full-scale data from two plants in the area were analysed to establish phosphate behaviour in the presence of iron. Titration experiments and mathematical modelling were performed to determine the role of ferric phosphate and hydroxide precipitation and other mechanisms that may potentially be involved in phosphorus removal. Iron addition is described in the model using a chemical equilibrium approach extended with surface charges and adsorption. The model verifies key observations from full-scale data: (a) extremely low orthophosphate levels can be achieved over a wide range of pH values, (b) a mixture of ferric phosphate and ferric hydroxide precipitate is forming with the hydroxide acting as sorbent, (c) molar ratios of Fe/P (iron dosed to phosphate removed) vary widely (1.0-3.9) based on the technology used and residual phosphate levels. The model will be a useful tool for engineers to optimise preliminary, simultaneous and tertiary P removal, both for design and plant operation.     

Experience with phosphorus removal and sludge handling and disposal in Flanders.

The way excess sludge must be disposed of is a key factor in the choice of the appropriate phosphorus removal technique at municipal wastewater treatment plants. In Europe the ongoing trend of tightening the sludge spreading rules called for a serious reduction of its agricultural utilisation and the expansion of the (co-)incineration disposal route, which led to a shift towards more sophisticated sludge handling techniques. This paper illustrates the impact of different sludge handling techniques on the performance of chemical and enhanced biological phosphorus removal at municipal WWTPs. The main conclusion is that although enhanced biological phosphorus removal is particularly sensitive to the problem of return liquors from sludge treatment processes indirect dewatering and anaerobic stabilisation cannot be discarded altogether when considering its implementation.     

Integrated constructed wetland systems: design, operation, and performance of low-cost decentralized wastewater treatment systems.

Several different types of constructed wetland systems are being used as decentralized treatment systems including surface-flow, subsurface-flow, vertical-flow, and hybrid systems. Archetypical wetland systems have design strengths and weaknesses, and therefore it should be possible to design combined (integrated) systems to optimize a number of important treatment processes. This study provides comparative efficacy data for two integrated wetland treatment systems (IWTS) designed to enhance treatment of medium strength wastewater generated from a pilot-scale intensive fish farm. Results from the twenty eight months study included consistently high removal of COD (84% +) and ammonia nitrogen (93%) in both systems. Initially, phosphorus removal was also high (>90%) in both systems, but removal efficacy declined significantly over time. Nitrate removal was significantly better in the system that provided sequential aerobic and anoxic environments. Short hydraulic retention times coupled with sustained removal of COD and ammonia indicate that the ReCip components could be a least-cost wastewater treatment technology in the decentralized market sector.     

Resource recovery from excess sludge by subcritical water combined with magnesium ammonium phosphate process.

The amount of excess sludge produced in municipal wastewater treatment plants in Japan is increasing every year as the urban population increases. Phosphorus in excess sludge could be a potential phosphorus resource since at present, phosphate rock is being exhausted all over the world. Every year, Japan imports large quantities of phosphorus from abroad but much is discharged as excess sludge. Therefore, the solubilization process, one method of recovering phosphorus from sludge, could be a promising solution. In this study, a subcritical water process, a new technology that solubilizes sludge under subcritical conditions, was applied before the phosphorus in sludge was recovered with the magnesium ammonium phosphate (MAP) process. As a result, the solubilization rate of excess sludge achieved approximately 80% and about 94-97% of the phosphorus could be recovered.