我国城市污水处理厂污泥产沼气的前景分析

污泥厌氧消化具有稳定污泥和回收能量以及处理后污泥可作农肥的突出优点.我国城市污水处理厂污泥多,污泥厌氧消化的推广空间巨大.污泥厌氧消化推广的主要问题是规模较小、投资高、技术复杂、维修量大等,而沼气利用不理想大大削弱了该工艺的优势.必须降低投资、简化运行和提高沼气利用的效益,加速研究配套政策,才能改变投入高、产出低的现状,才能使污泥厌氧消化成为污泥处理的首选工艺.     

污水处理厂污泥厌氧消化优化设计与运行探讨

对国内典型的污水处理厂污泥厌氧消化系统进行调研发现,厌氧消化系统的运行管理尚存在诸多问题。在总结白龙港污水处理厂污泥厌氧消化调试与运行管理经验的基础上,针对厌氧消化工艺存在的普遍性问题,提出了厌氧消化系统设计和运行管理方面的建议,以促进工艺设计优化,提高运行管理水平。     

上海市白龙港污水处理厂污泥厌氧消化工程设计

上海市白龙港污水处理厂升级改造后总规模为200万m3/d,其污泥处理工程规模1020t/d(以含水率80%计),是目前亚洲最大的污泥处理项目。白龙港污泥处理工程在对国内外污泥处理处置经验进行分析总结的基础上,采用了浓缩—中温厌氧消化—脱水—干化的处理工艺,介绍了该工程的工艺选择和具体设计情况。     

热水解厌氧消化工艺的分析和应用探讨

热水解厌氧消化工艺可提高污泥的水解效果和有机物降解率,增加沼气产量;杀灭污泥中病菌;缩短厌氧消化的停留时间、提高消化池内的污泥浓度,节省占地面积和土建工程投资;同时使消化后的污泥易于脱水,污泥体积减少。与传统的厌氧消化工艺比较,热水解厌氧消化工艺强化了污泥的减量化、稳定化、无害化和资源化的处理目标,当与后续热干化工艺结合时,可降低运行成本。从热水解技术的原理和形式出发,结合实际工程方案,对热水解厌氧消化工艺的可行性和应用中的问题进行了初步探讨。     

城镇污水污泥厌氧消化技术及能源消耗

我国城镇污水处理厂采用污泥稳定化处理的不到20%,在污泥稳定化方面与国外存在较大差距。厌氧消化技术可以实现污泥的减量化、稳定化和无害化,同时可利用沼气资源。结合《城镇污水处理厂污泥处理处置污染防治最佳可行技术指南(试行)》的编写,介绍了城镇污水处理厂的污泥厌氧消化技术、能源消耗和厌氧消化排放的污染物,为决策者和从业人员提供参考。     

污泥的自动升温高温好氧消化工艺介绍

自动升温高温好氧消化(ATAD)作为一种污泥稳定工艺,与中、高温厌氧消化和中温好氧消化相比具有反应速度快、停留时间短、占地少、能杀灭病原体、节约能量等诸多优点。对ATAD的运行条件、作用机理及其作用效果进行了综述。     

对《城镇污水处理厂污泥处理处置及污染防治技术政策》的解读

2009年2月住房和城乡建设部、环境保护部和科学技术部三部委联合颁布了<城镇污水处理厂污泥处理处置及污染防治技术政策>, 用以指导各地开展污水处理厂污泥处理处置工作.分析了我国城镇污水处理厂污泥处理处置面临的问题和原因,并对技术政策的有关要点进行解读.     

珠海市污水处理厂污泥处理处置探讨

在总结国内外常用污泥处理处置技术的基础上,结合珠海市污泥处理处置现状以及污泥特性,探讨其污泥处理工艺和处置设施厂址选择.建议珠海市中心城区污水处理厂污泥适宜的处置工艺为:半干化填埋和干化焚烧;并针对不同的工艺,对污泥集中处置设施厂址进行了综合比选.     

上海在建的三座大型城市污水处理厂介绍(一)--上海石洞口污水处理厂

介绍了上海市在建的三座大型污水处理厂的基本情况石洞口污水处理厂采用二级加强生物除磷脱氮工艺,白龙港污水处理厂采用一级加强物化法除磷处理工艺,竹园第一污水处理厂采用一级加强生物化学絮凝处理工艺;同时对三座污水处理厂的工艺流程,主要设计技术参数及污泥处理,总工程造价等进行了说明.     

新型冠状病毒肺炎疫情期间城镇再生水厂污泥处理处置运行实践

新冠肺炎疫情期间,污泥处理处置过程的安全性问题更加凸显.与此同时,由于污水水质及水量变化,北京市中心城区的污泥高级厌氧消化处理系统处于低负荷运行状态,对运行稳定性提出较大挑战.通过对污泥处理过程及出泥泥质特性分析,明确了污泥高级厌氧消化工艺在污泥稳定化及病原体灭活方面的优势.通过梳理新冠肺炎防控期间的经验做法,提出了污泥高级厌氧消化系统应对低负荷运行的具体举措.此外,针对污泥运输及后续利用环节,介绍了人员防护及区域消杀的建议.以期为疫情常态化防控期间,城镇污水处理厂污泥处理处置环节的安全稳定运行提供借鉴.     

The Ruhrverband sewage sludge disposal concept in the conflict between European and German standards and regulations.

The Ruhrverband, acting as a water association responsible for integrated water resources management within the entire natural river basin of the Ruhr, operates a network of 83 wastewater treatment plants (WWTPs) and connected sludge disposal facilities. According to German regulations, the disposal of sewage sludge containing more than 5% of organic dry solids will be prohibited as of 1 June 2005. In Germany, the only future alternative to incineration will be the agricultural utilization of sludge. However, this way of sludge disposal is presently the subject of critical discussions in Germany because of the organic and inorganic toxic substances, which may be contained in sewage sludge, despite the fact that very stringent standards are to be met by agricultural uses. On the other hand, application of sewage sludge to agricultural land is explicitly supported by the European Sewage Sludge Directive 86/278/EEC. In the face of this controversial situation the Ruhrverband has initiated, in 2000, the development of a comprehensive and sustainable sludge and waste disposal concept for all wastewater facilities it operates in the entire Ruhr River Basin. The concept includes de-central sludge digestion and dewatering and subsequent transport to two central sludge incineration plants. It is expected that in future not more than 5% of all sludges produced in Ruhrverband's WWTPs will be used in agriculture. That means, the major part of 95% will have to be incinerated.     

An investigation of agricultural use potential of wastewater sludges in Turkey--case of heavy metals.

Landfilling is one of the most common methods that are used in the final disposal of sludge world wide, as well as in Turkey. However, increasing sludge quantities and limited landfilling areas make this method difficult to apply. The use of sludge in agriculture presents a possible alternative for disposal. However, it also poses some risks to be evaluated. In this respect, it is important to identify the heavy metal content of sewage sludges because of its adverse health effects. This study aims to determine the heavy metal contents of sludges and wastewaters from three different wastewater treatment plants in Turkey. The selection of plants was carried out according to the different treatment technologies applied to wastewater and sludge in those plants. Heavy metal analysis of sludges and wastewaters was conducted using a microwave assisted digestion procedure. After sampling and analysis, the results show that all the related metal concentrations are below the values that are set in the Soil Pollution Control Regulation of Turkey. However, in two of the three plants, Zn and Ni concentration should be tracked carefully.     

Water reuse for irrigation from waste water treatment plants with seasonal varied operation modes.

Irrigation periods are usually limited to vegetation periods. The quality requirements for treated wastewater for disposal and for reuse are different. The reuse of water for irrigation allows partly the reuse of the wastewater's nutrients (N and P). Outside the irrigation period the water must be treated for disposal, thus nutrient removal is often required in order to avoid detrimental effects on the receiving surface water body. Only wastewater treatment plants with different operation modes for different seasons can realise these requirements. The nitrification is the most sensitive biological process in the aerobic wastewater treatment process. At low water temperatures the nitrifying bacteria need several weeks to re-start full nitrification after periods without NH4-removal. Therefore it is necessary to develop options for waste water treatment plants which allow a fast re-start of the nitrification process. Based on theoretical considerations and computer simulations of the activated sludge treatment process, one possibility for implementing a wastewater treatment plant with different seasonal operation modes is evaluated.     

城镇污水处理厂项目环境影响评价重点的研究

城镇污水处理厂作为一项环境保护工程,在发挥环境效益的同时,运行过程中排放的尾水、产生的恶臭和污泥等污染物对环境将产生不利影响。在进行污水处理厂项目环境影响评价时,应识别评价重点,目的是使环境影响预测和评价具有针对性,以发挥更大的环境效益。根据污水处理厂的工程特性,结合江门市江海污水处理厂工程环境影响评价的实践经验,提出污水处理厂环境影响评价应重点关注厂址环境合理性分析、污水处理工艺比选、尾水排放对水环境影响、恶臭对大气环境影响、污泥处置对环境影响等问题。     

小城镇污泥处理方法

随着城镇化进程的加快.城镇污水排放量也不断增加,污水处理迫在眉睫.污水处理过程中必然产生大量成分复杂的污泥如处理不当会对环境造成严重污染.污泥的处理、处置在污水处理中是不可或缺的,如何将产量巨大、成分复杂的污泥进行妥善安全地处理,已成为深受关注的重大课题.针对小城镇污泥的特征,提出了几种宜在小城镇实施的污泥处理与处置方法.     

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.     

Municipal sludge management and disposal in South Korea: status and a new sustainable approach.

Based on figures from 2002, 5216 ton/d of the municipal sludge is produced from 184 large municipal wastewater treatment plants in 111 cities with total treatment capacity of 19,229,745 m3/d. Even though the large amount of sludge disposal has depended greatly on ocean disposal and landfills until recently, the fraction of sludge reuse has gradually increased from 2.7% to 7%, since 1991. Due to a need of resources recovery from the sludge, high cost requirement of incineration and legislative regulation, recent new research is mainly focused on resources recovery and its reuse from the municipal sludge, such as high performance acid fermenter with pathogen reduction, crystallization (struvite and hydroxyapatite) using waste lime, cofermentation of municipal sludge with food waste, aerobic composting with P crystallization, vermistabilization, lime treatment, etc. Current research and practical activities with some efforts for the new technical development as well as environmental law and regulation are reviewed.     

Production of thermostable protease enzyme in wastewater sludge using thermophilic bacterial strains isolated from sludge.

The volume of sludge produced annually is very high and poses serious disposal problems. The traditional methods of sludge disposal produce secondary pollutants. Therefore, the alternate or suitable solution is reuse of sludge in an ecofriendly approach. Biotechnology is an interesting tool to add value to the processes involved in wastewater and wastewater sludge disposal/reuse. In this context, a study was carried out on thermophilic bacterial strains that produce thermostable proteases. The bacterial strains were first isolated from municipal wastewater sludge. In contrast to the conventional strains used in industries, like Bacillus sp., the new strains were Gram-Negative type. In semi-synthetic medium, a maximal protease activity of 5.25 IU/ml (International Unit per ml) was obtained at a pH of 8.2 and at a temperature of 60 degrees C, which is higher than the stability temperature of 37 degrees C for a similar protease obtained from the conventional producer Bacillus licheniformis. Moreover, growth and protease activity of the strains were tested in wastewater sludge. It is expected that the complexity of sludge could stimulate/enhance the protease production and their characteristics. In conclusion, reuse of wastewater sludge will help to reduce their quantity as well as the value-added products produced will replace chemical products used in industries.     

Sludge as source of energy and revenue.

Sludge is a residue/product from wastewater treatment plants and contains most of the contaminants released during human activities. Some stringent environmental regulations on sludge treatment and disposal exist in many countries. This has resulted in increasing interest in sludge treatment methods that encourage sludge reduction and improvement in biogas production during anaerobic digestion processes. This work demonstrates the first exploitation of valuable energy from homogenised sludge at technical scale with mass reduction. The optimal combination of sludge homogenisation at relatively low pressures using a modified high-pressure homogeniser led to the success of this unique project. Results showed that about 30% more energy could be obtained from thickened and disrupted sludge than from untreated samples. The energy produced was higher than that invested during disruption and digestion processes. About 23% sludge reduction was also observed with no increase in chemical oxygen demand. This new process can produce extra energy for local electrification and heating the digester while the sludge reduction provides economic benefits. Concentration of sludge causes reduction in investment cost on digester as well as reduction in operational time for sludge dewatering.     

白龙港污水处理厂生物处理污泥产量分析与预测

准确了解城市污水处理厂的污泥产量,不仅对污水处理厂的运行管理有指导意义,也有利于后续污泥的处理与处置。对上海白龙港污水处理厂生物处理工艺污泥产量的设计值、实际运行值进行计算,分析不同污泥产量计算方法的特点。并对重新启用初沉池后污泥产量的变化进行了详细的测算和分析,结果表明,重新启用初沉池后污泥产量比超越初沉运行时有所减少,减轻了后续污泥处置负荷。