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1.
The CO2 absorption capacities of potassium glycinate, potassium sarcosinate (choline, proline), mono-ethanolamine (MEA), and tri-ethanolamine were evaluated to find the optimal absorbent for separating CO2 from gaseous products by a CO2 purification process. The absorption loading, desorption efficiency, cost, and environmental tolerance were assessed to select the optimal absorbent. MEA was found to be the optimum absorbent for separating the CO2 and H2 mixture in gaseous product. The maximum absorption loading rate was 0.77 mol CO2 per mol MEA at temperature of 20°C and absorbent concentration of 2.5 mol/L, whereas desorption efficiency was 90% by heating for 3 h at 130°C. MEA was found to be an optimal absorbent for the purification process of CO2 during gaseous production.  相似文献   
2.
This article reviews the application of environmental impact assessment (EIA) procedures and practices to three watershed modification projects situaled in western Canada. These ventures were justified for accelerating regional economic development, and cover the period during which public concerns for protecting the environment rapidly made their way into the national political agenda. An historical account and analysis of the situation, therefore, seems desirable in order to understand the development of EIA processes, practices, and methodologies since the start of construction of the first project in 1961. This study concludes that there has been good progress in predicting and evaluating environmental and related social impacts of watershed modification proposals. However, a number of obstacles need to be overcome before EIA can firmly establish itself as an effective planning tool. These difficulties include jurisdictional confusions and conflicts, division of authority and responsibility in designing and implementing appropriate mitigative and monitoring measures, lack of tested EIA methodologies, and limited availability of qualified human resources. A number of conclusions and suggestions are offered so that future watershed modification proposals may be planned and implemented in a more environmentally sustainable fashion. These include: (1) EIA processes must be completed before irrevocable decisions are made. (2) Any major intrusion into a watershed is likely to impact on some major components of the ecosystem(s). (3) Mitigation costs must form part of the benefit-cost analysis of any project proposal. (4) Interjurisdictional cooperation is imperative where watersheds cross political boundaries. (5) The EIA process is a public process, hence public concerns must be dealt with fairly. (6) The role of science in the EIA process must be at arms length from project proponents and regulators, and allowed to function in the interest of the protection of the environment and public health and safety. The views expressed here are the authors’ own and do not necessarily reflect those of FEARO and/or other government agencies and officials involved in the review of these projects.  相似文献   
3.
The ability of pre-oxidation to overcome polycyclic aromatic hydrocarbons (PAH) recalcitrance to biodegradation was investigated in creosote contaminated soil. Sand and peat artificially spiked with creosote (quality WEI C) were used as model systems. Ozonation and Fenton-like treatment were proved to be feasible technologies for PAH degradation in soil. The efficiency of ozonation was strongly dependent on the water content of treated soil samples. The removal of PAH by Fenton-like treatment depended on the applied H2O2/soil weight ratio and ferrous ions addition. It was determined that the application of chemical oxidation in sand resulted in a higher PAH removal and required lower oxidant (ozone, hydrogen peroxide) doses. The enhancement of PAH biodegradability by different pre-treatment technologies also depended on the soil matrix. It was ascertained that combined chemical and biological treatment was more efficient in PAH elimination in creosote contaminated soil than either one alone. Thus, the combination of Fenton-like and the subsequent biological treatment resulted in the highest removal of PAH in creosote contaminated sand, and biodegradation with pre-ozonation was found to be the most effective technology for PAH elimination in peat.  相似文献   
4.
论环境产业   总被引:1,自引:0,他引:1  
本文在可持续发展视角下,把环境的保护、修复、维护的生产活动及与之直接相关的服务活动称为环境产韭,包括发挥减少、避免污染环境作用的资源再利用鼗和发挥治理污染物与修复、改善环境作用的环境维护业.通过探讨环境产业的内涵、发展历程、运行机制和在产业体系中的位置与作用,指出环境产业是在法规保障下政府强行推动产生和发展起来的,是产业体系中不可缺少的重要组成部分;考虑自然环境对社会行为的影响,改进政府行为构建适台环境产业与传统产业协调发展的经济体制是加快发展环境产业的关键.  相似文献   
5.
The European Operational Smog (EUROS) integrated air quality modelling system has been extended to model fine particulate matter (PM). From an extended literature study, the Caltech Atmospheric Chemistry Mechanism and the Model of Aerosol Dynamics, Reaction, Ionisation and Dissolution were selected and recently coupled to EUROS. Currently, modelling of mass and chemical composition of aerosols in two size fractions (PM2.5 and PM10–2.5) is possible. The chemical composition is expressed in terms of seven components: ammonium, nitrate, sulphate, elementary carbon, primary inorganic compounds, primary organic compounds and secondary organic compounds. Calculated PM10 concentrations and chemical composition are presented for two summer months of the year 2003 (1 July to 31 August).  相似文献   
6.
湖州市埭溪镇污水处理厂的设计规模,近期为2万m^2/d,远期为3万m^2/d,其污水处理工艺采用改良式A^2/O工艺,污泥处理工艺采用带式浓缩脱水一体机。文中着重介绍了工程设计参数、处理工艺流程及其设计特点。  相似文献   
7.
基于模糊层次综合法的炼铁厂评价模型及应用研究   总被引:4,自引:0,他引:4  
运用模糊层次综合评价法建立炼铁厂安全评价的模型,该模型能有机地将炼铁厂的安全管理、设备设施、人员和环境等因素结合起来,依据各因素对系统安全影响的大小,决策者可对其采取相应的改进措施以有效地控制事故的发生。通过对炼铁厂安全性的分析,其评价结果和现实情况基本相符,能较为全面反映整个系统的安全性和各因素对系统安全性的影响大小,为炼铁厂的安全评价提供了一种有效的综合评价方法。  相似文献   
8.
爆炸事故过程分析中不确定性问题处理方法   总被引:1,自引:0,他引:1  
针对事故过程分析中的不确定性问题,指出了不确定问题在危险分析中的重要性及处理该问题的复杂性和难点,列出了几种基于非线性数学方法处理不确定问题的基本方法,如微分法、MonteCarlo模拟、Fourier方法、响应表面法等,并对之进行了比较.建议在处理事故过程的不确定性时采用Monte Carlo模拟.  相似文献   
9.
焦化废水处理过程中产生的焦油、污泥和结晶杂盐等固相物质,既有资源属性,又有污染特性,但目前缺乏基于能源、经济及环境影响方面的评估.本研究阐述了3类固相物质的形成机制,建立了质量当量计算及处置方法评价模型.以宝武集团韶关钢铁股份有限公司焦化厂(二期)焦化废水处理工程的A/O/H/O(厌氧/好氧/水解/好氧)流化床工艺作为考察对象,利用工程运行参数和水质统计数据进行固相物质的产量推算,结果发现,焦油、物化污泥、生物污泥(含水率为80%)和工业杂盐的产率分别为0.186、5.80、4.24和1.97 kg·m-3.通过处置方法评价模型明确了焦油焚烧、污泥热解、结晶杂盐分盐提纯后工业应用是最佳处置方案,在60 m3·h-1废水处理规模的固相物质处置过程中,每年约产生1177 MWh的能源,获得135.0万元的经济效益,排放627.0 t CO2,表明能源回收、经济效益和环境影响的协同存在.  相似文献   
10.
为弄清饮用水O3-BAC深度处理工艺过程中细菌群落的时空分布和动态变化规律,本研究以我国南方某O3-BAC深度处理工艺水厂为研究对象,采用NovaSeq6000高通量测序技术对夏季和冬季各工艺单元出水及滤砂和活性炭生物膜等细菌群落进行解析.结果表明,出厂水pH、浊度、CODMn、菌落总数等指标均满足《生活饮用水卫生标准》(GB5749-2006)的要求.夏季细菌群落多样性明显高于冬季,活性炭生物膜的细菌群落多样性高于滤砂生物膜;混凝沉淀、臭氧化和消毒是影响细菌群落多样性的主要工艺单元.水样和生物膜样品绝对优势菌门均为变形菌门(Proteobacteria),且主要菌门组成大体相同,但细菌群落门水平相对丰度存在一定的时空差异,属水平上差异则更为明显.此外,检测到的条件致病菌属主要包括芽孢杆菌属(Bacillus)、不动杆菌属(Acinetobacter)、假单胞菌属(Pseudomonas)和分支杆菌属(Mycobacterium),且其所占核心微生物OTUs数目不受季节性影响.水温和生物可降解溶解性有机碳(BDOC)是显著影响细菌群落分布的主要水质参数.以上研究结果表明,O3-BAC深度处理工艺过程中细菌群落具有时空变化特性,并可为饮用水微生物安全保障提供支撑.  相似文献   
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