Optimization of regional hazardous waste management systems: an improved formulation

The planning and design of regional hazardous waste management system (RHWMS) involves selection of treatment and disposal facilities, allocation of hazardous wastes and waste residues from generator to the treatment and disposal sites and selection of the transportation routes. An improved formulation based upon multi-objective integer programming approach is presented to arrive at the optimal configuration of RHWMS components. This formulation addresses important practical issues like unique characteristics of the hazardous wastes reflecting on waste–waste and waste–technology compatibility. A utility function approach is presented to integrate both cost and risk related objectives. An illustrative case example is presented to demonstrate the usefulness of the improved formulation as a tool which can be used by environmental planning agencies in regional planning for hazardous waste management.     

废弃电器电子产品产生量测算方法探究

选取我国废弃电器电子产品中回收处理数量最多、获得政策基金补贴最多的电视机产品,通过对其销量、最长使用年限、报废高峰期、报废系数的分析,采用市场供给A模型测算其报废产生量,并进一步对废弃电视机产生量测算结果与实际处理量做对比分析,提出废电视机产生量的修正方法。最终测算得到废电视机产生量为4 213万台,与同年电视机的实际处理量持平。     

Studies on process optimization of biodiesel production from waste cooking and palm oil

This work investigated the optimisation of biodiesel production from waste cooking oil (WCO) and palm oil using a two-step transesterification process for WCO and base catalysed transesterification for palm oil. Transesterification reactions were carried out to investigate the effects of prepared catalyst CaO, methanol/WCO and methanol/palm oil ratio and temperature on the yield of biodiesel. A series of experiments were conducted to determine the best conditions for biodiesel production, using methanol/oil ratio between 4:1 and 11:1 and contact time varying between 2 and 4 h. Biodiesel yield of around 90 and 70% was obtained for palm and waste cooking oil at the methanol/oil ratios of 6:1 and 8:1 at temperature of 60 °C for reaction time of 4 h using prepared CaO as catalyst. The physicochemical properties of palm and WCO biodiesel were carried out using standard methods, while the fatty acid profile was determined using gas chromatography. The investigation concludes that biodiesel obtained from palm and waste cooking oil was within the specified limit.     

电感耦合等离子体原子发射光谱法测定废水中的铊

采用电感耦合等离子体原子发射光谱仪(ICP-AES)测定废水中铊,并对测定波长、介质及其酸度、共存元素干扰等因素进行分析和条件优化,使该方法在0 mg/L~5.00 mg/L范围内线性良好,相关系数为0.999 9。方法检出限为22μg/L,该方法对铊标准样品测定的结果在保证值范围内,4份废水样7次测定结果的RSD为0.2%~0.8%,实际废水样品的加标回收率为98.0%~100%。     

废酸的综合治理与资源化研究进展

通过对废酸处置行业的现状调查研究,探讨了双极膜法、结晶法、中和法、喷雾焙烧法、离子交换法、化学转化法等典型废酸处置工艺的特点及存在的问题。以提高环境和经济效益为前提,针对废酸处置行业普遍存在的重金属处理问题,提出将电解法、双极膜法和离子交换法等关键技术集成和改性,形成具有耐酸和重金属高效去除等能力的针对废酸特点的新工艺等建议。     

高浓度氨氮废水处理技术及其发展趋势

介绍了高浓度氨氮废水的主要来源及其危害性,对国内外主要的高浓度氨氮废水处理工艺进行了分析和对比,并阐述了其发展趋势,为处理高浓度氨氮废水工艺技术的选择提供了参考。     

英国废物管理许可证制度及其对中国的启示

英国废物管理许可证制度是世界上最早的、最为完善的许可证制度之一。然而,目前国内对该制度的研究甚少。本文在参考大量国外相关文献的基础之上,对于这一制度进行了系统的介绍和评析,并结合我国的现实情况,进一步分析了该制度对完善和发展我国废物管理许可证制度的启示。     

中国危险废物管理现状研究

分析了我国危险废物的产生特点,概述了我国危险废物管理法规体系,以及目前国内危险废物管理的研究情况,指出我国危险废物管理中存在的问题,并提出相应的对策。     

Two Measured Parameters Correlated to Participation Rates in Curbside Recycling Schemes in the UK

Local authorities in the United Kingdom are currently changing their approach towards recycling as they attempt to meet legislative targets. An important part of this drive is the provision of an effective curbside recycling service and it is vital to understand the parameters that influence the performance of the system offered. In this article, three primary datasets, collected from over 1400 households each, are examined for parameters correlated to participation rates. Two measured parameters were found that are not commonly identified in previous studies of curbside recycling schemes, and they are shown to merit further investigation as useful tools for planning purposes. One is the number of types of material collected; participation rates are greater for schemes collecting more materials. The second is the number of households situated on the same road; the lower the number, the higher the participation rate. In both cases, evidence of the measured correlation is presented, justifying their usefulness for planning. The multiple underlying factors causing the correlations are not identified here, but suggestions are made for further studies.     

Usability of food industry waste oils as fuel for diesel engines

Two cogeneration units were each fitted with a prechamber (IDI) diesel engine in order to test the feasibility of using waste oils from the food industry as a fuel source, and additionally to test emissions generated by the combustion of these fuels. Esterified waste oils and animal fats as well as mustard oil were tested and compared to the more or less "common" fuels: diesel, rapeseed oil and rapeseed methyl ester. The results show that, in principle, each of these fuels is suitable for use in a prechamber diesel engine. Engine performance can be maintained at a constant level. Without catalytic conversion, the nitrogen oxides emissions were comparable. A significant reduction in NO(x) was achieved through the injection of urea. Combining a urea injection with the SCR catalytic converter reduced NO(x) emissions between 53% and 67%. The carbon monoxide emissions from waste oils are not significantly different from those of "common" fuels and can be reduced the same way as of hydrocarbon emissions, through utilization of a catalytic converter. The rate of carbon monoxide reduction by catalytic conversion was 84-86%. A lower hydrocarbon concentration was associated with fuels of agricultural origin. With the catalytic converter a reduction of 29-42% achieved. Each prechamber diesel engine exhibited its own characteristic exhaust, which was independent of fuel type. The selective catalytic reduction of the exhaust emissions can be realized without restriction using fuels of agricultural origin.