污水处理厂污泥消化系统设计与运行管理经验浅谈

郑州于新庄污水处理厂(40×104m3/d)是淮河流域最大的污水处理厂,其污泥利用厌氧消化进行稳定处理及浓缩脱水。所产沼气用来驱动鼓风机,余热配合沼气锅炉加热消化污泥。本文总结了整个污泥消化系统设计、运行管理的经验与不足,并提出今后污泥消化系统设计工作中应注意的几个问题。     

污水厂污泥消化系统设计运行经验小结

本文介绍了两座污水处理厂污泥厌氧消化的设计。以郑州某污水处理厂的实际运行情况说明设计的合理性与不足之处,并小结了消化系统设计应注意的几个方面。     

白龙港污水厂污泥流化床干化系统设计与研究

污泥干化是污水处理厂市政污泥处理处置过程中的一个重要环节。白龙港污水处理厂作为亚洲规模最大的污水处理厂,已建成并成功运行了国内首座污泥厌氧消化+干化处理工程,以及目前全世界规模最大的污泥单独干化焚烧项目,均采用流化床干化工艺对污泥进行干化。工程应用中,流化床干化处理能力均可满足设计要求,并可充分实现与污泥消化系统及污泥焚烧系统的有机结合。干化热源、系统换热方式的选择充分考虑了不同衔接工艺的特点,节约了能源和资源消耗。流化床干化系统能够安全、稳定运行,干化系统产生的冷凝水、载气等得到妥善处置,臭气污染物得到控制。     

无接种污泥的厌氧消化系统启动策略研究

以国内最大的污泥厌氧消化系统--上海市白龙港污水处理厂厌氧消化系统的调试启动为依托,研究了两种无污泥接种启动方案的效果.当消化罐内的初始状态为原污泥,且在10 d后以不同投配率投加原污泥时,约需25 d便可实现系统的成功启动,但启动过程中存在酸化的风险,而采用变投配率方式投加污泥可以在一定程度上缓解VFA的积累.当消化罐内的初始状态为清水,且在之后以不同投配率投加原污泥时,用时超过40 d才可成功启动系统,且污泥浓度达到设计值所需的时间较长,不过其酸化风险较小.该研究成果可为白龙港污水处理厂的污泥厌氧消化系统及国内同类工程的启动提供借鉴.     

北方地区污泥厌氧消化工艺应用现状分析

通过对我国北方地区108座大型污水处理厂污泥处理工艺的调研,总结了污泥厌氧消化工艺在我国北方大型污水处理厂的应用现状.结果显示,在108座污水处理厂中,共有27座采用厌氧消化工艺,其中具有代表性的9座污水厂中仅有3座正常运行.针对采用污泥厌氧消化工艺的污水处理厂,分别从工艺类型、污泥泥质、消化池池型、污泥搅拌系统、沼气利用以及系统运行管理等方面对污泥厌氧消化系统的运行状况进行了对比分析,探讨了污泥厌氧消化工艺在我国北方大型城市污水处理厂应用中存在的主要问题,并指出了解决方向.     

白龙港污水处理厂污泥厌氧消化系统的设计和调试

白龙港污泥处理工程主要处理白龙港污水处理厂200×104 m3/d污水处理产生的污泥,采用浓缩、中温厌氧消化、污泥脱水和部分脱水污泥干化处理工艺,消化产生的沼气用于加热消化池污泥,多余的沼气作为能源干化脱水污泥。干化处理后冷凝水的余热回收辅助用于污泥消化系统供热。介绍了污泥厌氧消化系统的设计参数、工艺特点及调试情况,可供设计人员参考。     

郑州市马头岗污水处理厂污泥热干化系统工艺设计

郑州市马头岗污水处理厂污泥热干化工程将污泥厌氧消化处理产生的沼气首先用于脱水污泥的热干化处理,将热干化尾气中的热量回收用于厌氧消化系统污泥的加热及消化罐的保温,通过能源的重复利用,在无需外加能源的情况下,实现了污泥厌氧消化+热干化系统的能量自平衡。该工程的成功运行对城镇污水处理厂污泥处理处置工艺选择具有示范意义。     

高碑店污水处理厂污泥厌氧消化系统恢复运行的经验

主要介绍高碑店污水处理厂二期污泥厌氧消化系统在长期停运后,恢复运行过程中进行的检修、测试及启动等方面的情况。总结了二期消化系统恢复运行所需的检测流程、消化系统启动时厌氧菌的培养过程以及提高污泥培养效率的经验。     

地下污水处理厂污泥干化车间通风除臭系统设计

分析了地下污水处理厂污泥干化车间臭气处理的难点和重点及应对措施,介绍了广州地下污水处理厂污泥干化车间通风除臭系统及空调系统的设计。试运行效果显示,污泥干化车间臭气浓度得到了有效控制,臭气排放水平远高于目前国内标准要求。     

白龙港污水处理厂污泥厌氧消化系统的运行分析

对目前国内规模最大的上海市白龙港污水处理厂污泥厌氧消化系统的运行情况进行了系统分析。该污泥厌氧消化系统的设计规模为204 tDS/d,于2011年5月完成启动调试,稳定运行后的产气量受进泥流量和性质的影响呈现较为规律的季节性变化,单位污泥实际年均产气量为10.73 m3/m3污泥,沼气产率为0.82 m3/kgVSS。厌氧消化系统运行中存在的较为突出的问题包括浮渣泡沫、鸟粪石结晶、池内积砂等,分析了其产生原因,并给出了相应的解决措施。     

UK Developments in Sewage Sludge Processing

A considerable amount of research and development has been undertaken in the UK during the last 25–30 years in the field of sewage sludge processing. The research has been sponsored mainly by the water utilities with the objective of improving process efficiency and reliability and reducing costs. Government-funded research has focused mainly on the environmental aspects of sludge disposal to land and to the sea.
Finding ways of reducing sludge production has proved difficult, but one new method of sewage treatment has some advantages in this respect.
Arising from the research on sludge processing, (a) new methods of characterization of sludge have been developed, (b) an improved method for the design and operation of gravity thickeners has been successfully implemented, (c) advances have been made in the process of heated anaerobic digestion, and (d) an effective system for aerobic thermophilic digestion of sludge at small works has been established. A new method for measuring sludge filtrability – the PFT meter – has been developed, and the economics of flocculation have been improved by the introduction of a new type of mixer. An improved method for controlling the operation of filter presses is now available.
The problems of odour nuisance from sludge operations may now be controlled using biological systems to treat odorous air.     

广州珠江河段水质环境保护整治的现状与对策

水环境资源是人类赖以生存的资源。城市污水治理工程是水环境的重要基础设施工作。阐述了广州市水环境状况、排水工程及主要污水处理厂的现状。针对水环境资源存在的问题,提出了在污水处理中,对污泥的处置、臭气污染的控制、河涌的截污和生态修复等对策和措施。     

郑州市污泥堆肥处理工程的设计

郑州市污泥堆肥处理工程处理规模为600 t/d,采用好氧堆肥工艺处置三个污水处理厂的剩余污泥.介绍了工艺流程及发酵槽、混料仓、除臭系统等各处理单元的设计参数,可为相关工程提供参考.     

Operating Experiences of Sludge Disinfection and Stabilization at Colburn Sewage Treatment Works, Yorkshire

A NEW integrated sludge treatment plant was installed at Colburn sewage treatment works (STW) in 1986. The plant comprises a number of novel features including a continuous gravity thickener features including a continuous gravity thickener, a pasteurization unit using submerged combustion of digester gas for sludge heating, a peat-bed odour control system, and a 'pump-our/pump-in'prefabricated anaerobic digester. Plant operation is controlled automatically by a computer system The performance of the thickener has been in accordance with predictions and has achieved at least a halving of raw sludge volume. The submerged combustion plant has consistently heated the sludge to 70°C with high efficiency of gas utilization before the anaerobic digestion stage. Some problems were experienced with the continuity of supply of the raw sludge but overall the plant has performed very satisfactorily with the production of a high quality disinfected and stabilized sludge for use by local farmers.     

Removal of bis(2-ethylhexyl) phthalate at a sewage treatment plant

Bis(2-ethylhexyl) phthalate (DEHP) concentrations were measured at different stages in a full-scale sewage treatment plant (STP) and mass balances were calculated. The DEHP load to treatment process coming from the sewer system and the internal load comprising returned supernatants and filtrate from sludge treatment and excess secondary sludge were at the same level. The DEHP removal efficiency from the water phase at the STP was on average 94% of sewage DEHP, the main removal process being sorption to primary and secondary sludges. On average 29% of DEHP was calculated to be removed in the biological nitrifying-denitrifying activated sludge process, which was much less than expected from laboratory biodegradation studies described in literature. Monoethylhexyl phthalate, the primary biotransformation product of DEHP, was not detected at any treatment stage. Approximately 32% of DEHP in sewage was removed during anaerobic digestion of the sludge, while 32% remained in the digested and dewatered sludge.     

The balance of heavy metals through a sewage treatment works I. Lead,cadmium and copper

Concentrations of lead, cadmium and copper have been determined in the sewage sludges, sewages and effluent of a sewage treatment works. Treatment at this works is by primary sedimentation prior to biological treatment in a diffused air activated sludge plant. By analysis of composite samples corresponding to a 24-h input of raw sewage to the works, a mass balance of metals through the works has been estimated. The partition of the metals from raw sewage into the settled sewage and primary sludge, and from the settled sewage into the activated sludge and final effluent has been quantified.     

Influence of anaerobic digestion on the carbon footprint of various sewage sludge treatment options

This paper describes the results of a model set up to determine carbon footprints for sludge treatment solutions with and without standard or advanced anaerobic digestion. Complete and 'gate' (up to the point the sludge leaves the sewage works gate) footprints were calculated. The lowest carbon footprints corresponded with advanced digestion options, which reduced downstream energy and transport (hence carbon) requirements regardless of the endpoint of the sludge. The lowest complete carbon footprint solution coincided with advanced digestion, followed by drying with energy recovery. However, this option had the highest gate carbon footprint. In terms of gate carbon footprint, land application of an advanced digested sludge cake had the smallest footprint, followed by land application of dried pellets and finally incineration.     

Environmental aspects of the use of NTA as a detergent builder

The behaviour, fate and significance of the detergent builder nitrilotriacetic acid (NTA) has been reviewed with particular reference to the removal of NTA during wastewater treatment and the effects of NTA on heavy metal solubility both during treatment and in the receiving environment. It is concluded that NTA removal during secondary biological treatment is subject to considerable variation, both temporal and between works as a result of changes in NTA load, temperature, water hardness and treatment process parameters. As a result of such variability, effluent NTA concentrations may be sufficient to mobilise heavy metals resulting in metal contamination of receiving waters and potable waters, particularly in areas of low effluent dilution and high water re-use. Removal of NTA during primary sedimentation and septic tank treatment is concluded to be predominantly due to adsorption to the sludge solids while removal in anaerobic sludge digestion is subject to operational characteristics of the treatment works. Disposal of NTA contaminated sludge to land may contaminate groundwaters and affect heavy metal speciation, while the disposal of contaminated sludge or sewage to sea may result in toxic algal blooms, in addition to effects on metal speciation.     

Effect of sewage treatment on faecal sterols

Levels of faecal sterols were measured in samples taken from various stages of the sewage treatment process. Final effluent samples contained reduced levels of sterols which was attributed to removal mainly by physical processes in secondary treatment of sewage. Sludge samples contained large concentrations of sterols, due to the insolubility of the compounds in water. Treatment of sludge by digestion gives increased concentrations of coprostanol. Epicoprostanol was detected in digested sludge samples, although only trace amounts occurred in primary sludge.     

青岛麦岛污水处理厂污泥消化及热电联产运行管理经验

污泥厌氧消化/热电联产是一项重要节能工艺技术,对于提高资源和能源利用效率意义重大。完善的管理是保证污泥消化及热电联产系统稳定高效运行的关键环节。麦岛污水处理厂将Multiflo~?Trio初沉污泥与生物滤池剩余污泥进行混合,形成沼气产率较高的混合污泥,并进行中温厌氧消化,所产沼气进入热电联产系统用于发电及沼气锅炉,回收余热作为污泥消化及厂区采暖热源。10余年来,麦岛污水处理厂的污泥消化及热电联产系统实现了安全、稳定、高效的运行,保证了污泥的资源化、减量化、无害化处理及利用。介绍了青岛麦岛污水处理厂污泥厌氧消化及热电联产的运行情况,探讨如何在污泥消化及热电联产间做好运行管理和调控,使之形成良性循环。