运用LCA方法分析污水再生处理的成本效益

运用生命周期评价(LCA)方法,以西安市北石桥污水净化中心的污水处理与再生利用全过程为例进行环境影响评价,通过清单分析、当量计算和权重分析等一系列分析过程,计算出污水处理过程的投入成本及污水再生处理前后对环境的影响,得出污水在经过处理后,能够很大程度上减小其对环境的影响,从而产生环境正效益。该研究明确了污水处理在环境保护中的重要地位,同时对优化污水处理与再生利用工艺过程具有重要的参考价值和指导意义。     

Life cycle assessment of fuel selection for power generation in Taiwan

Life cycle assessment (LCA) was applied to performance data from 1997-2002 to evaluate the environmental impacts of the energy input, airborne emission, waterborne emission, and solid waste inventories for Taiwan's electric power plants. Eco-indicator 95 was used to compare the differences among the generation processes and fuel purification. To better understand the environmental trends related to Taiwan's electric power industry, three fuel scenarios were selected for LCA system analysis. Results indicate that there are differences in characteristic environmental impact among the 13 power plants. Scenario simulation provided a basis for minimizing environmental impacts from fuel selection targets. Fuel selection priority should be a gas-fired combined cycle substituted for a coal-fired steam turbine to be more environmentally friendly, particularly in the areas of the greenhouse effect, acidification, winter smog, and solid waste. Furthermore, based purely on economic and environmental criteria, it is recommended that the gas-fired combined cycle be substituted for the oil-fired steam turbine.     

Life Cycle Assessment of Fuel Selection for Power Generation in Taiwan

Abstract

Life cycle assessment (LCA) was applied to performance data from 1997–2002 to evaluate the environmental impacts of the energy input, airborne emission, waterborne emission, and solid waste inventories for Taiwan’s electric power plants. Eco-indicator 95 was used to compare the differences among the generation processes and fuel purification. To better understand the environmental trends related to Taiwan’s electric power industry, three fuel scenarios were selected for LCA system analysis. Results indicate that there are differences in characteristic environmental impact among the 13 power plants. Scenario simulation provided a basis for minimizing environmental impacts from fuel selection targets. Fuel selection priority should be a gas-fired combined cycle substituted for a coal-fired steam turbine to be more environmentally friendly, particularly in the areas of the greenhouse effect, acidification, winter smog, and solid waste. Furthermore, based purely on economic and environmental criteria, it is recommended that the gas-fired combined cycle be substituted for the oil-fired steam turbine.     

Benefits of clean development mechanism application on the life cycle assessment perspective: a case study in the palm oil industry

This study performed an assessment on the beneficial of the Clean Development Mechanism (CDM) application on waste treatment system in a local palm oil industry in Malaysia. Life cycle assessment (LCA) was conducted to assess the environmental impacts of the greenhouse gas (GHG) reduction from the CDM application. Calculations on the emission reduction used the methodology based on AM002 (Avoided Wastewater and On-site Energy Use Emissions in the Industrial Sector) Version 4 published by United Nations Framework Convention on Climate Change (UNFCC). The results from the studies showed that the introduction of CDM in the palm oil mill through conversion of the captured biogas from palm oil mill effluent (POME) treatment into power generation were able to reduce approximate 0.12 tonnes CO2 equivalent concentration (tCO2e) emission and 30 kW x hr power generation per 1 tonne of fresh fruit bunch processed. Thus, the application of CDM methodology on palm oil mill wastewater treatment was able to reduce up to 1/4 of the overall environment impact generated in palm oil mill.     

Pharmaceuticals and personal care products found in the Great Lakes above concentrations of environmental concern

The monitoring of pharmaceuticals and personal care products (PPCPs) has focused on the distribution in rivers and small lakes, but data regarding their occurrence and effects in large lake systems, such as the Great Lakes, are sparse. Wastewater treatment processes have not been optimized to remove influent PPCPs and are a major source of PPCPs in the environment. Furthermore, PPCPs are not currently regulated in wastewater effluent. In this experiment we evaluated the concentration, and corresponding risk, of PPCPs from a wastewater effluent source at varying distances in Lake Michigan. Fifty-four PPCPs and hormones were assessed on six different dates over a two-year period from surface water and sediment samples up to 3.2 km from a wastewater treatment plant and at two sites within a harbor. Thirty-two PPCPs were detected in Lake Michigan and 30 were detected in the sediment, with numerous PPCPs being detected up to 3.2 km away from the shoreline. The most frequently detected PPCPs in Lake Michigan were metformin, caffeine, sulfamethoxazole, and triclosan. To determine the ecological risk, the maximum measured environmental concentrations were compared to the predicted no-effect concentration and 14 PPCPs were found to be of medium or high ecological risk. The environmental risk of PPCPs in large lake systems, such as the Great Lakes, has been questioned due to high dilution; however, the concentrations found in this study, and their corresponding risk quotient, indicate a significant threat by PPCPs to the health of the Great Lakes, particularly near shore organisms.     

Prioritizing research for trace pollutants and emerging contaminants in the freshwater environment

Organic chemicals have been detected at trace concentrations in the freshwater environment for decades. Though the term trace pollutant indicates low concentrations normally in the nanogram or microgram per liter range, many of these pollutants can exceed an acceptable daily intake (ADI) for humans. Trace pollutants referred to as emerging contaminants (ECs) have recently been detected in the freshwater environment and may have adverse human health effects. Analytical techniques continue to improve; therefore, the number and frequency of detections of ECs are increasing. It is difficult for regulators to restrict use of pollutants that are a human health hazard; scientists to improve treatment techniques for higher priority pollutants; and the public to modify consumption patterns due to the vast number of ECs and the breadth of literature on the occurrence, use, and toxicity. Hence, this paper examines literature containing occurrence and toxicity data for three broad classes of trace pollutants and ECs (industrials, pesticides, and pharmaceuticals and personal care products (PPCPs)), and assesses the relevance of 71 individual compounds. The evaluation indicates that widely used industrials (BPF) and PPCPs (AHTN, HHCB, ibuprofen, and estriol) occur frequently in samples from the freshwater environment but toxicity data were not available; thus, it is important to establish their ADI. Other widely used industrials (BDE-47, BDE-99) and pesticides (benomyl, carbendazim, aldrin, endrin, ethion, malathion, biphenthrin, and cypermethrin) have established ADI values but occurrence in the freshwater environment was not well documented. The highest priority pollutants for regulation and treatment should include industrials (PFOA, PFOS and DEHP), pesticides (diazinon, methoxychlor, and dieldrin), and PPCPs (EE2, carbamazepine, βE2, DEET, triclosan, acetaminophen, and E1) because they occur frequently in the freshwater environment and pose a human health hazard at environmental concentrations.     

循环流化床锅炉燃煤技术热电厂生命周期评价

运用生命周期评价方法,应用Gabi5.0软件对采用循环流化床锅炉燃煤技术的热电企业进行资源耗竭和环境影响分析,计算各生产单元生命周期清单的全球变暖潜值、酸化效应潜值、富营养化潜值、非生物资源耗竭潜值、人体毒性潜值以及光化学烟雾和臭氧生成潜值等主要环境影响类型,对燃煤发电过程进行生命周期评价。结果表明,全球变暖和非生物资源耗竭为发电运行过程中主要的环境影响因素,分别占53%和15.05%;锅炉燃烧阶段的环境影响最重,占整个生命周期影响值的77.12%,并且除生物耗竭潜值外的其他5项指标均为发电运行阶段各个单元中最高。采用SNCR脱硝技术减少燃烧过程中NOx的排放量,并对该技术方案进行生命周期评价,比较方案实施前后的环境影响。     

生命周期评价研究进展

生命周期评价作为一种评价产品、工艺过程或活动在整个生命周期中环境影响的工具,在国际上广受关注。现对它的概念、发展历程、技术框架、特征及存在问题作简单的介绍,并对其未来发展作了展望。     

城市污水处理环境效益量化分析

运用生命周期评价（LCA）方法对西安市北石桥污水净化中心污水处理工艺从其原材料开采和加工开始直到污水厂施工建设、处理运行以及废弃拆除的生命周期全过程资源消耗、能耗和环境影响进行了识别和量化分析，同时结合一维水质稀释模型，提出污水处理环境效益估算模型。采用最大污染权重因子对模型进行计算，结果表明，采用深度处理比常规二级处理多产生1 708.52×10⁹kJ的环境正效益。     

Performance evaluation of a decentralized wastewater treatment system in India

A Decentralized Wastewater Treatment System (DEWATS) provides an economically feasible and efficient wastewater treatment solution especially in developing countries. It has an enormous potential for developing a sustainable environmental sanitation system. In this study, the treatment efficiency of eight DEWATS plants was evaluated in the state of Maharashtra, India, for their performance in terms of selected physico-chemical parameters of the wastewater. Although the efficiency of some of the plants was lower than that reported in literature, the effluent quality of all the plants was within the permissible discharge limits of the Central Pollution Control Board for all the parameters. Comprehensive assessment of Plant I was carried in terms of its technical and socio-economic aspects. Moreover, LCA tool has been utilized to evaluate the environmental impacts of the operation stage of DEWATS. The midpoint, CML 2001 (April 2015) methodology was adopted, in which 11 impact categories were considered. From the life cycle impact assessment and interpretation, the main impacts are identified as releases of COD, P-PO₄^3?, and N-NH₄⁺ to water bodies and disposal of sludge. Due to negligible energy consumption, the operation stage was found to be less damaging to the environment. It was concluded that DEWATS can be a good alternative for treating wastewater with negligible energy and chemical consumption.

     

Assessment models and dynamic variables for dynamic life cycle assessment of buildings: a review

Environmental Science and Pollution Research - Life cycle assessment (LCA) is widely used to quantify the environmental performance of buildings. Recently, the potential temporal variations in the...     

General prevention and risk minimization in LCA A combined approach

Methods for life cycle assessment of products (LCA) are most often based on the general prevention principle, as opposed to the risk minimization principle. Here, the desirability and feasibility of a combined approach are discussed, along with the conditions for elaboration in the framework of LCA methodology, and the consequences for LCA practice. A combined approach provides a separate assessment of above and below threshold pollution, offering the possibility to combat above threshold impacts with priority. Spatial differentiation in fate, exposure, and effect modelling is identified to play a central role in the implementation. The collection of region-specific data turns out to be the most elaborate requirement for the implementation in both methodology and practice. A methodological framework for the construction of characterization factors is provided. Along with spatial differentiation of existing parameters, two newly introduced spatial parameters play a key role: the sensitivity factor and the threshold factor. The practicability of the proposed procedure is illustrated by an example of its application. Providing a reasonable data availability, the development of separate LCA characterization factors for the respective assessment of pollution levels above and below environmental threshold values seems to be a feasible task that may add to LCA credibility.     

膜生物反应器工艺污水处理厂设计进水水质的确定

城市污水处理厂进水水质是工程设计的基本参数,进水水质的测定分析对污水处理厂的设计具有重要意义。对无锡市城北污水处理厂的现状进水水质进行了调查和分析,提出按照水质指标浓度出现的频率确定污水处理厂设计进水水质的方法,并针对采用的膜生物反应器(MBR)工艺的特点,提出:(1)根据实测数据按照一定的保证概率可以用来确定城市污水处理厂设计进水水质;(2)为了使水质的确定更加符合设计工程的实际情况,根据实测数据分析确定设计进水水质指标时,一般还需要进行趋势性调整和季节性调整;(3)确定合理的指标浓度与流量,以此为依据进行反应池的工艺设计,同时要校核夏季温度高、浓度低、流量大和冬季温度低、浓度高、流量小的工况是否满足处理要求,然后取冬、夏季校核值以及未作季节性调整设计值中最不利情况作为设计值,才能充分保证出水达到处理要求。     

污水处理中几种去除药物及个人护理用品方法的机理及效果比较

目前广泛分布在环境中的药物及个人护理品（pharmaceuticals and personal care products, PPCPs）在环境中的迁移、转化和处理已成为环境科学与工程研究的一个新的领域。污水处理厂排水是PPCPs进入环境中的主要途径。介绍了污水处理过程中传统活性污泥法、膜处理技术以及氧化处理等主要工艺对PPCPs的去除机理，并对去除效果进行了比较。以传统活性污泥法及在其改进后的膜处理技术为基础的大部分现有污水处理厂只能够去除一部分PPCPs，并且主要通过吸附（如对于吐纳麝香、佳乐麝香、萨利麝香等脂溶性较高的有机物）和生物降解作用（如对于布洛芬，17β-雌二醇，雌酮等易反应的有机物）。然而，吸附了PPCPs的污泥通过土壤施肥又将PPCPs带入土壤中，进而会渗滤到地下水，或随径流水进入地表水中。因此，PPCPs并没有从根本上得以去除。相比之下氧化处理工艺（如氯化、臭氧氧化、紫外辐射）或这些工艺的组合能够将大部分的PPCPs进行氧化，去除效果明显优于以上2种技术。然而，氧化后产物的种类和毒理性需要更深入的研究。     

城市污水中有关新型微污染物PPCPs归趋研究的进展

药品和个人护理用品 (PPCPs) 是最近十年引起关注的新型有机微量污染物，其引起的环境安全风险受到人们越来越多的关注。一些研究发现，城市污水处理厂出水中存在着一定浓度的PPCPs，城市污水排放是PPCPs进入环境的一条重要途径。从城市污水中PPCPs的分析方法、迁移转化和减量化技术研究等三个方面综述了有关PPCPs在城市污水中归趋的研究进展，介绍了我国城市污水中PPCPs的研究现状；并对在我国进行相关研究提出了建议，以期推动相关研究的开展。     

Occurrence and removal of six pharmaceuticals and personal care products in a wastewater treatment plant employing anaerobic/anoxic/aerobic and UV processes in Shanghai,China

The occurrence and removal of six pharmaceuticals and personal care products (PPCPs) including caffeine (CF), N, N-diethyl-meta-toluamide (DEET), carbamazepine, metoprolol, trimethoprim (TMP), and sulpiride in a municipal wastewater treatment plant (WWTP) in Shanghai, China were studied in January 2013; besides, grab samples of the influent were also taken every 6 h, to investigate the daily fluctuation of the wastewater influent. The results showed the concentrations of the investigated PPCPs ranged from 17 to 11,400 ng/L in the WWTP. A low variability of the PPCP concentrations in the wastewater influent throughout the day was observed, with the relative standard deviations less than 25 % for most samples. However, for TMP and CF, the slight daily fluctuation still reflected their consumption patterns. All the target compounds except CF and DEET, exhibited poor removal efficiencies (<40 %) by biological treatment process, probably due to the low temperature in the bioreactor, which was unfavorable for activated sludge. While for the two biodegradable PPCPs, CF, and DEET, the anaerobic and oxic tank made contributions to their removal while the anoxic tank had a negative effect to their elimination. The tertiary UV treatment removed the investigated PPCPs by 5–38 %, representing a crucial polishing step to compensate for the poor removal by the biologic treatment process in winter.     

Assessment of the sustainability of technology by means of a thermodynamically based life cycle analysis

Life cycle analysis is one of the tools in the assessment of the sustainability of technological options. It takes into account all effects on the ecosystem and the population which may endanger the possibilities of current and future generations. However, the main bottleneck in current LCA methodologies is the balancing of different effects, being all quantified on different scales. In this work, a methodology is proposed, which allows one to quantify different effects of the production, consumption and disposal of goods, and services on a single scale. The basis of the methodology is the second law of thermodynamics. All production, consumption and disposal processes affecting the ecosystem and the population, are quantified in terms of loss of exergy. The exergy content of a material is the maximum amount of energy which can be transformed into work at given environmental conditions. Next to the elaboration of the methodology, the new approach is illustrated by examples of the production of synthetic organic polymers, inorganic building insulation materials and different waste gas treatment options.     

Applying waste management scenarios in the Peloponnese region in Greece: a critical analysis in the frame of life cycle assessment

The aim of this paper is to apply life cycle assessment in the waste management sector, in order to compare the environmental performance of different waste management methods. The methods that are studied are: landfilling, aerobic and anaerobic biological treatment, incineration and recycling, focusing on mass and energy balances and the environmental performance of each applied scenario. The Peloponnese Region in Greece was selected as a case for the application of this methodology and more specifically its largest municipalities, where a significant amount of waste is presented. The conducted LCA study proves the necessity of the adoption of an integrated waste management system and indicates its principal objectives by measuring environmental impacts. Thermal scenario contributes significant to the mitigation on the Greenhouse Gases. On the other hand, separation at source and recycling practices provides significant benefits to the abiotic depletion impact.     

Ecological assessment of the environmental impacts of the kerosene burning in jet turbines and its improvement assessment

The burning of kerosene in jet turbines is investigated for two reference flights with a Boeing 747-400 and an Airbus A320-200, representing the typical Lufthansa planes for long and middle distance. The ecological evaluation is performed by Life Cycle Assessment (LCA). Formation of condensation trails, which is a specific environmental impact caused by air traffic, has to be considered in addition to established LCA impact categories. Based on the ecological assessment, an improvement assessment is performed. Environmental performance of diesel fuel during the combustion in car engines is analysed based on available publications. The relevant parameters for the environmental impact of the combustion of diesel (aromatics content, reduction of sulphur content, the reduction of the density and raising of the cetane number) are discussed with regard to improvements of the exhaust qualities of kerosene. A reduction of the aromatics content promises to improve the emission of soot which should be further investigated.     

Edible Protein Energy Return on Investment Ratio (ep-EROI) for Spanish Seafood Products

Life cycle assessment (LCA) has developed into a useful methodology to assess energy consumption of fishing fleets and their derived seafood products, as well as the associated environmental burdens. In this study, however, the life cycle inventory data is used to provide a dimensionless ratio between energy inputs and the energy provided by the fish: the edible protein energy return on investment (ep-EROI). The main objective was to perform a critical comparison of seafood products landed in Galicia (NW Spain) in terms of ep-EROI. The combination of energy return on investment (EROI) with LCA, the latter having standardized mechanisms regarding data acquisition and system boundary delimitation, allowed a reduction of uncertainties in EROI estimations. Results allow a deeper understanding of the energy efficiency in the Galician fishing sector, showing that small pelagic species present the highest ep-EROI values if captured using specific fishing techniques. Finally, results are expected to provide useful guidelines for policy support in the EU’s Common Fisheries Policy.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-013-0426-2) contains supplementary material, which is available to authorized users.