电源项目环境管理和企业环保职责

针对当前国家环保法规、制度的执行力度加大和电源项目环境管理要求日益提高的现状,分析了企业所担负的环保职责,探讨了强化项目前期、基建、生产中环保全过程管理的思路.     

典型220 kV交流输电线路电磁场分布

通过理论计算和实际测量,揭示220 kV输电线路下的电磁场强度分布情况.从实际测量结果来看,输电线路下电磁场强度高于环境背景值,但均低于国家标准限值.     

渤海湾燃煤电厂脱硫工艺选择

海水脱硫方案因其具有运行费用低等优点受到青睐.近几年,随着电力的快速发展,渤海湾出现了三十多座发电厂,竞相采用海水脱硫方案.而渤海湾属于半封闭的海湾,湾内海水与外海海水交换周期至少长达200年,区域的海流最大流速仅为外海的50%,扩散条件不太理想,污染物的长期累积情况很难确定.那么在渤海湾海域建设的滨海电厂采用海水脱硫是否可行呢?分析研究认为不宜在渤海湾选择海水脱硫工艺.     

浅谈大功率柴油机余热发电

介绍了中山柴油机发电厂余热发电技改项目,并分析论述了利用大功率柴油机排烟余热发电的优点.在油价高企的背景下,实施余热发电是节能环保的有效措施之一.     

Analysis of Products Generated from the Thermal and Catalytic Degradation of Pure and Waste Polyolefins using Py-GC/MS

The possibility of transforming waste plastics into valuable hydrocarbons via catalytic cracking and reforming is attracting increasing interest. Pyrolysis coupled with Gas Chromatographic separation and Mass Spectrometry detection (Py-GC/MS) has been used in this work to study the product selectivity of various catalysts in the conversion of pure and residual polyethylene samples into hydrocarbon products. Five acid solids of comparable aluminium contents but different textural and acid properties were tested as catalysts, including three zeolites (standard ZSM-5, nanocrystalline n-ZSM-5 and Beta) and two mesostructured solids (Al-MCM-41 and Al-SBA-15). Thermal cracking of the pure and residual polymers generated a similar range of products to each other, with a high proportion of linear paraffins and olefins of varying lengths. The presence of zeolitic materials resulted in complete elimination of heavy linear products, an increase in the light hydrocarbon fraction and a marked selectivity towards the formation of single-ring aromatic species, particularly benzene, toluene and xylene. Aromatic formation was particularly notable with the small crystal size n-ZSM-5 (aromatic selectivity up to 53.9%) and less marked in the case of standard ZSM-5 (up to 36.4%) and Beta zeolite (up to 35.0%). Mesostructured catalysts like Al-MCM-41 and Al-SBA-15 favoured the production of light C₂–C₅ hydrocarbons (up to 57.9%) while the formation of aromatic products was significantly lower than with zeolitic materials. The paper examines the extent and the causes for this product selectivity and discusses its connection with the acid and textural properties of each catalyst. It was also observed that, under the experimental conditions employed, the products generated were not significantly affected by the nature and origin of the polymers employed.     

Catalytic conversion of waste tyres into valuable hydrocarbons

Tyre recycling has become a necessity because of the huge piles of tyres that represent a threat to the environment. The used tyres represent a source of energy and valuable chemical products. Waste tyres were pyrolysed catalytically in a batch reactor under atmospheric pressure. Calcium carbide was used as a catalyst to explore its effect on pyrolysis product distribution. The effect of temperature, amount of catalyst and time on the yields of the pyrolysed products was investigated. Char yield decreased with increase of pyrolysis temperature while total gas and liquid yields increased. The liquid fraction was obtained with boiling point up to 320 °C. The physical and chemical properties of the pyrolysed products obtained were characterized. The catalytic pyrolysis produced 45 wt.% aromatic, 35 wt.% aliphatic and 20 wt.% of polar hydrocarbons. The distillation data showed that ∼80% of oil has boiling point below 270 °C which is the boiling point for 50% of distilled product in commercial diesel oil. The oil fraction was found to have high gross calorific value; GCV (42.8 MJ kg⁻¹). Its Specific gravity, viscosity, Kinematic viscosity, freezing point and diesel index were also within the limits of diesel fuel. The char residues were studied to investigate their characteristics for use as a possible adsorbent. Surface area of char before and after acid demineralization was determined to determine the adsorptive features for waste water treatment.     

流动注射-氢化物发生-原子吸收法测定土壤中微量砷

用混酸消解土壤试样，用体积分数为20％的盐酸作酸介质，质量分数为1．5％的硼氢化钾作还原剂，体积分数为1％的盐酸作载液，采用流动注射-氢化物发生三-原子吸收法定量测定土壤中的微劈砷。通过实验确定，在原子化温度为920℃、土壤中共存元素含量低于5mg／kg时对测定无干扰。该方法的榆出限为0．5μg/L，线性范嘲为5～100μg/L．相对标准偏差为0．89％，平均回收率达98．99％：     

电力系统抗震可靠性研究与分析综述

地震是最可能造成电力系统遭受严重破坏的自然灾害。对电力系统的震害特点进行了一些研究和介绍,针对这些特点提出了提高电力系统抗震可靠性的措施和建议,并对电力系统抗震可靠性研究现状及发展趋势作了综述。     

Waste management of electric and electronic equipment: comparative analysis of end-of-life strategies

This article analyzes diverse aspects of the waste management of electronic and electric equipment. The scope of the study focuses on end-of-life strategies currently implemented in industrialized economies such as Japan, the United States, and the European Union. The objective is a comparative analysis of such strategies in order to identify logistic issues that may contribute to the further improvement of waste management policies. The results indicate that although all strategies follow the extended producer responsibility principle, in practice several logistic differences arise due to particular interpretations of the concept. In general, it was observed that a direct comparison is rather difficult since the strategies consider different legal frameworks, they cover different types and numbers of products, and the resultant mass flows and related operational costs are highly context-dependent variables. Therefore, it is not possible to indicate which strategy presents the highest overall efficiency. The study concludes that a little contribution is feasible if the advantages and weaknesses of the models depicted and discussed here are considered in further regulatory decisions.Extended version of the poster presentation A comparative analysis of end-of-life strategies for home appliances in Japan, America, and the European Union, accepted at the 31st Annual Meeting of Environmental Systems Research, Japan Society of Civil Engineers (JSCE), October 24–25, 2003, Kitakyushu, Japan     

粉煤灰综合利用研究进展

介绍了粉煤灰的物理化学性质。综述了粉煤灰在建材制造、建筑工程、道路工程、农业、废水处理和催化反应中的应用现状以厦未来的应用前景。