城市污水系统温室气体排放与对策研究

污水系统是完成城市减排目标的主体,但在其建设和运行过程中需要消耗大量能源并排放温室气体,存在广阔的节能减排空间。对污水输送、污水处理和污泥处理等过程的温室气体排放途径进行了调研分析,在此基础上提出相应的减排对策,并提出应在规划理念、工艺选择和运行管理的方案比选中,引入碳尺概念,就排放的温室气体量进行分析研究,推动低碳排水系统的发展。     

污水处理厂温室气体的产生、核算和减量研究进展

从产生影响因素、核算方法与低碳处理技术三个方面阐述污水处理厂直接和间接温室气体排放的研究进展。介绍近期国内外关于N₂O、CH₄和CO₂产生的研究成果，简述排放量核算的排放系数法、现场测定法、模型法和生命周期法研究现状及适用目标，重点阐述N₂O与CH₄排放因子的研究及尚待完善的内容。分析“截污降碳”新要求下运行参数优化需要考虑的新要素，介绍部分硝化/厌氧氨氧化、微藻技术等自养脱氮耦合进水能源“碳捕捉”的低碳处理技术。认为我国污水处理厂降低温室气体间接排放量还有很大提升空间，能源供给方式有必要调整，低碳处理技术辅以厌氧消化-热电联产等能源回收措施，是未来污水处理厂实现可持续发展的有效途径。     

三峡水库减排温室气体效应的初步分析

三峡水库的温室气体排放问题十分复杂,从地貌与气候特征、水文特性、植被状况等方面对三峡水库释放温室气体的特性做了简要分析。三峡水库现阶段不可能释放大量的甲烷,但会有一定的二氧化碳释放。初步定性分析了三峡水库综合效益对温室气体的减排效应。与水库产生的温室气体相比,三峡工程在清洁能源生产中的温室气体减排效应以及减少防洪物资生产产生的温室气体的环境效益十分明显。     

灌区农田温室气体减排潜力研究 ——以江苏省濉汴河灌区为例

农业生产活动具有碳源和碳汇的双重效应,为研究濉汴河灌区温室气体减排潜力,对灌区采取适当的减排固碳措施提供依据和建议,分别从稻田 CH4 排放、农用地 N2O 排放、农用柴油 CO2 排放、排灌电力生产造成的 CO2 排放以及作物生长季碳通量等方面,估算灌区2021 年温室气体排放量和吸收量,并针对相关指标进行敏感性分析,研究分析其对灌区温室气体排放量的影响程度。结果表明：濉汴河灌区 2021 年温室气体净排放量约为 7.21 万 t CO2 当量,且主要的排放组成是农田释放的 CH4 和 N2O。     

中国长江三峡集团公司科技与环境保护部李翀教授:三峡水库不是CH4威胁源

中国长江三峡集团公司科技与环境保护部李翀教授24日在"气候变化"专题讨论会上作了题为《三峡水库温室气体监测与减排效益》的发言。李翀介绍了对三峡水库水体温室气体排放监测的范围、方法、过程与结果。李翀介绍说,通过对三峡水库温室气体的原位监测研究发现,三峡水库不是CH4威胁源,三峡水库温室气体排放水平低,三峡水电是低碳能源。三峡工程作为我国水电开发的典型,其拥有的巨大的低碳、减排效益,体现了水电这一能源形式     

水库温室气体排放问题初探

水库温室气体排放问题不仅引起社会各界广泛的关注,也影响到水电站及水库建设的未来发展趋势。根据国内外研究成果,从水电站的能量密度和单位发电量的水库面积等方面比较世界主要地区水库特性;通过分析水库特性、水库运行方式和所处地理环境,探讨水库温室气体排放的影响;最后,讨论三峡水库的温室气体问题。分析认为,与火力发电比较,水力发电具有明显减排的优势,包括三峡在内的绝大多数水库温室气体排放是很小的,对气候变化影响更是微乎其微。     

中国CDM项目发展现状及案例分析

2005年正式生效的《京都议定书》旨在限制全球温室气体排放总量,是国际社会共同应对全球性气候变化的重要举措。该议定书提出的清洁发展机制（CDM）规定发达国家可以通过提供资金、技术等方式帮助发展中国家实施减排来完成自己的温室气体减排义务.中国是最重要的发展中国家之一,CDM机制为我国节能减排、促进可持续发展提供了良好的机遇,也给我国相关行业发展带来巨大的商机。水电、风电是清洁可再生能源,对减少温室气体排放具有重要作用,也是开发CDM项目的重要领域。通过两个案例,分析了开发CDM项目的优越性,并对我国CDM开发提出一些看法。     

玉瓦水电站生命周期温室气体排放研究

基于生命周期评价方法,以玉瓦水电站为工程背景,研究中小型长引水式电站温室气体排放情况。分析了生命周期各阶段温室气体排放情况,并与大型水电站及火力发电的温室气体排放进行比较,玉瓦水电站生命周期温室气体排放表现十分优异,大力开发水电能有效地减低温室气体的排放。因此,在项目前期阶段确定开发方式及电站规模时,除技术经济因素外,还有必要考虑水电站生命周期内环境影响,评估减排效益,阐明水力发电的清洁性与优质性。     

气候变化与清洁发展机制(三)

1EU-ETS简介为了履行《京都议定书》规定的减排目标,欧盟启动全球第一个温室气体排放交易体系——欧盟温室气体排放交易体系(European Union Emission Trading Scheme,简称EU-ETS)。自2005年1月运行以来,EU-ETS已发展为全球最大的温室气体排放交易体系。     

从运营角度分析污水处理工艺选择面临的挑战及对策

近些年,我国污水处理厂建设规模及数量飞速发展,在缓解环境压力、节能减排方面取得了明显成效.但有一个不容忽视的问题就是,污水处理厂设计水平及质量与后期运行效果密切相关,从设计环节保证后期的可靠、稳定运行显得至关重要.结合对国内外污水处理厂的调研结果,从运营角度,剖析了污水处理厂设计将面临的各种考验,并提出了一些合理建议.     

Anaerobic digestion: impact of future greenhouse gases mitigation policies on methane generation and usage.

The debate as to whether carbon dioxide, methane, nitrous oxide and other greenhouse gas emissions will become subject to increasing regulation, increased restrictions, and probably to some form of carbon tax, has moved from a simple "yes" or "no" to "when". Wastewater treatment plants will be significantly impacted by increased energy costs and by specific regulations and/or penalties associated with emissions of methane and nitrous oxide. In this paper, the greenhouse gases emissions of different wastewater process options are estimated. The paper outlines the increasing need for wastewater treatment plants to factor greenhouse gas mitigation issues into their medium- as and long-term strategies, and identifies anaerobic enhouse as processes as being at the core of such strategies. Further, the paper identifies a number of key research challenges to be addressed if such strategies are to play a larger role in attenuating the likely impacts of GHG mitigation requirements on wastewater treatment plant design and operation.     

Calculation of energy recovery and greenhouse gas emission reduction from palm oil mill effluent treatment by an anaerobic granular-sludge process

Conventional aerobic and low-rate anaerobic processes such as pond and open-tank systems have been widely used in wastewater treatment. In order to improve treatment efficacy and to avoid greenhouse gas emissions, conventional treatment can be upgraded to a high performance anaerobic granular-sludge system. The anaerobic granular-sludge systems are designed to capture the biogas produced, rendering a potential for claims of carbon credits under the Kyoto Protocol for reducing emissions of greenhouse gases. Certified Emission Reductions (CERs) would be issued, which can be exchanged between businesses or bought and sold in international markets at the prevailing market prices. As the advanced anaerobic granular systems are capable of handling high organic loadings concomitant with high strength wastewater and short hydraulic retention time, they render more carbon credits than other conventional anaerobic systems. In addition to efficient waste degradation, the carbon credits can be used to generate revenue and to finance the project. This paper presents a scenario on emission avoidance based on a methane recovery and utilization project. An example analysis on emission reduction and an overview of the global emission market are also outlined.     

The climate footprint: a practical tool to address climate change.

Waternet supplies clean and safe drinking water to the homes of almost one million Amsterdam citizens, and also collects and treats the resulting wastewater, ensuring its safe discharge back into the water system. Climate change poses a growing challenge. Firstly Waternet is affected by the consequences of climate change, such as longer periods of drought and heavier bursts of rainfall. Secondly, the company also plays a role in causing climate change, as emissions from the Amsterdam water chain contribute to global warming. This paper aims to focus attention on mitigation as an inseparable part of adaptation-programmes. The Climate Footprint methodology is applied to the integrated Amsterdam water chain: from the point of withdrawing water from the surface/groundwater water system for drinking water production, to the point of returning the purified wastewater to the surface water/groundwater system. In-between, the water is pre-treated with chemicals, transported, purified by dune-filtration, again treated for drinking water quality, distributed over the area of Amsterdam, used in households and industries, collected from there by sewers and pumps, transported to purification plants and finally again treated with chemicals and purified to end with acceptable surface water quality. The whole process generates CO(2)-emissions in three different ways: * Sewage treatment transforms the remains of human food consumption into CO(2). These emissions do not originate from fossil fuels, but from food. They remain in a short carbon cycle and do not contribute to global warming. In fact, the sludge remaining from the purification plant is an important energy source. * Transport and purification processes require energy; this results in direct emissions e.g. in the case of fuel or natural gas use, and indirect emissions in the case of electricity. * The use of chemicals and materials for construction, transport systems, and all other facilities and services to keep the system running does require suppliers of these goods and services to consume energy and thus causes indirect emission. An inventory of these three different types of emissions is made for the (about) 1990 situation, the 2004 situation, and prognosticated for the 2007 situation. The 2004 situation reveals a 0.16 ton CO(2) equivalent emission per person. Compared to the worldwide 4 ton emission per person, this would mean a 4% contribution from the urban water system. With all the improvements scheduled, a 50% elimination of greenhouse gas emissions looks attainable for the 2007 situation. Further possibilities for emission reductions may be found by talking to suppliers about the indirect emissions.     

Development of China’s Coal-Fired Power Plants in the Coming Years

Power Technology and Engineering - Among the measures aimed at reducing emissions of technogenic “greenhouse gases” (primarily CO2), China plans to halve the total installed capacity of...     

Climate change mitigation by recovery of energy from the water cycle: a new challenge for water management

Waternet is responsible for drinking water treatment and distribution, wastewater collection and treatment, and surface water management and control (quality and quantity) in and around Amsterdam. Waternet has the ambition to operate climate neutral in 2020. To realise this ambition, measures are required to compensate for the emission of 53,000 ton CO(2)-eq/year. Energy recovery from the water cycle looks very promising. First, calculations reveal that energy recovery from the water cycle in and around Amsterdam may contribute to a total reduction in greenhouse gas emissions up to 148,000 ton CO(2)-eq/year. The challenge for the coming years is to choose combinations of all the possibilities to fulfil the energy demand as much as possible. Only then the use of fossil fuel can be minimized and inevitable greenhouse gas emissions can be compensated, supporting the target to operate climate neutral in 2020.     

Estimations of municipal point source pollution in the context of river basin management.

Integrated presentation of total emissions on catchment scale is prerequisite for many tasks in integrated management of point and diffuse sources of pollution. This paper will focus on emissions of nutrients from municipal point sources. Based on calculations of discharges of N, P from households into wastewater and on the detailed evaluation of data from 76 municipal wastewater treatments plants, this paper presents ranges of specific loads of inhabitants and population equivalents in the raw wastewater. In addition data of these treatment plants have been evaluated in respect of the treatment efficiency for nitrogen and phosphorus (average reduction rates) dependent on the design characteristic (with or without nitrification, denitrification or enhanced phosphorus removal). The results of the investigation show that the specific N and P loads from households in Austria lie within the range 1.6-2.0 g P/(inhabitant.d) and 11- 13 g N/(inhabitant.d). The specific contribution of industries to municipal wastewater varies between 0.3 and 2.0 gP/(pe.d) and 0 and 13 g N/(pe.d) with average values of 1.3 g P/(pe.d) and 6.5 g N/(population equivalent (pe)/d). As average values for municipal wastewater (contributions from household and industry) this leads to specific influent loads of 1.5 g P/(pe.d) and 8.8 g N/(pe.d). Average treatment efficiencies of treatment plants are for instance 50% nitrogen removal in treatment plants with nitrification and 80% in treatment plants with nitrification/denitrification. For phosphorus a removal of about 85% can be expected where the treatment plant was designed for enhanced phosphorus removal. Finally a method for load estimations based on standard values as mentioned above was tested for the estimation of emission from municipal point sources of selected regions.     

污水处理厂有毒有害及易燃易爆气体在线监测系统建设与应用

小红门污水处理厂是较早建设有毒有害及易燃易爆气体在线监测系统的污水处理厂之一.介绍了小红门污水处理厂监测系统的建设背景、实施方案及应用效果.系统包括在线检测、视频检测、广播等3个子系统.系统的应用促进了安全生产,有利于保障职工职业健康,取得了较好的经济效益和社会效益.建议城镇污水处理厂的设计中增设此种监测系统.     

Control of odour emission in wastewater treatment plants by direct and undirected measurement of odour emission capacity

Odour emissions from wastewater treatment plants (WWTPs) are considered to be the main causes of disturbance noticed by the exposed population and have relevant impacts on both tourism economy and land costs. Odour impact from WWTPs is generated by primary and secondary odour emissions. Primary odour emissions are related especially to the wastewater type and variability discharged into the sewer and directed to the WWTP, and to the wastewater collection and sewage system. Secondary odours are related to the treatment units of the plant. Several studies describe the key role of primary odour emissions and how they are strongly related to odour impacts of WWTPs. In this way, a opportune characterization of the emission capacity of primary odour could be an effective way to control odour emission in the WWTPs. In this study the odour emission capacity (OEC) of different domestic sewers was described and investigated; a correlation between the OEC and the main physical-chemical parameters of wastewater quality was also carried out. Results of this study identify the optimum conditions for sampling and measuring OEC in wastewaters and define its dependence by wastewater quality. These results can contribute to setting the standards for the maximum odourant content of wastewater that are discharged into the publicly owned sewage system.     

南方地区水稻节水灌溉的综合效应研究进展

水稻节水灌溉技术的应用对于提高水肥利用效率、减少面源污染和温室气体排放、维持生物多样性和保障粮食安全具有重要意义。近年来,水稻节水灌溉的生态环境效应日益凸显,并逐渐受到重视。阐述了南方地区水稻节水灌溉模式的应用现状,分析了主要节水灌溉模式的特点及其节水、经济、环境、生态效应,指出在田间节水灌溉的综合效应、节水灌溉对温室气体排放的综合影响机理、对杂草和动物多样性调控机制的研究和节水灌溉模式的多准则评价方面的不足,从开展节水灌溉与节水、增产、环境、生态之间的互馈机制、节水灌溉条件下温室气体排放的协同和微生物驱动机制、水管理措施下稻田杂草群落之间的竞争和群落调控机制的研究以及利用考虑多重效应的综合评价指标体系进行灌溉模式优选等方面提出下一步的研究方向。