Overview of non-hazardous solid waste in the small island state of Mauritius

In Mauritius, solid waste disposal has been a cause for concern since the 1980s. Currently, there is no segregation of waste and some 1200 tonnes of solid waste are generated daily by the 1.24 million inhabitants of the island. As processes such as recycling and composting are still in their infancy stage, most of the waste generated have to be disposed of at the sole landfill. The solid waste management practices of 1980s and early 1990s are no longer compatible with the changing composition and quantity of wastes now generated. As a result, there is an urgency to review the whole waste management system and come forward with sustainable solutions.This paper presents an overview of the disposal of non-hazardous solid waste in Mauritius and provides recommendations for improving the current disposal system.     

Sustainable solid waste management in sub-Saharan African cities: application of system thinking and system dynamic as methodological imperatives in Kinshasa,the Democratic Republic of Congo

This paper is based on a review of the methodological approaches associated with solid waste management (SWM) in the context of sub-Saharan African (SSA) cities. Using Kinshasa, the capital of the Democratic Republic of the Congo, as a case study, the paper proposes a new way of looking at solid waste in the bid to come up with alternative methods to improve the plight of SWM. A combination of qualitative research methods and system analysis have been employed to evaluate the causal relationships observed in contemporary SWM systems in Kinshasa. This paper argues that there is an absence of coherent and broad-based approaches to SWM in Kinshasa as is common in other SSA countries. Empirical evidence suggests that contemporary SWM strategies and approaches developed on a global scale which have increasingly been adopted by the Congolese national and local government authorities have proven inadequate to address the SWM realities on a local level. Using system thinking and system dynamics, this paper attempts to develop a feasible methodological framework focusing on the formulation of an appropriate approach to improve SWM in Kinshasa. It is argued that new ways of approaching the complexity that exists in SWM will facilitate the adoption of technologies and innovative ways of thinking and managing solid waste in a more sustainable, socially, and environmentally accepted manner.     

关于固体废物污染环境防治法修改的研究思考

2019年6月,《中华人民共和国固体废物污染环境防治法（修订草案）》（以下简称草案）经国务院审议通过,并初次提请全国人大常委会审议。草案修订力度之大,值得充分肯定。同时,草案还存在不少提升空间,需要进一步深入研究。本文以习近平生态文明思想为引领,按照中央全面依法治国委员会第二次会议提出的加强立法统筹、立改废释并举要求,剖析了当前我国固体废物环境管理及其立法修法中面临的挑战,以及存在的突出问题;并从明确固废污染防治立法原则、强化政府统筹管理、明确各部门职责、强化区域统筹、完善跨区域转移监管机制、统筹国内外相关法律法规及政策文件等方面提出了完善草案的建议,以期为我国固废管理决策和草案修改提供参考。     

Effects of planned expansion of waste incineration in the Swedish district heating systems

Recent targets for reduced amounts of waste to landfills in Sweden will result in a large increase in waste incineration with recovery of energy, used primarily for district heating. The aim of this study is to investigate what changes in the usage of other fuels and technologies for district heat production would be caused by this increase. A questionnaire was sent out to the largest district heating companies, and simulations in an energy systems model were carried out. The analysis shows that increased waste incineration reduces the demand for other fuels, especially biomass, for district heat production. The effects include reductions in operating hours as well as the avoidance or postponement of investments in new plants for district heat production. Increased waste incineration will also lead to a greater use of district heating in Sweden.     

生物接触氧化法在炼油废水回用处理中的应用

利用生物接触氧化法对炼油厂的外排污水进行深度处理,在曝气时间大于3h的情况下,可以有效地降低COD、氨氮,伴随硝化反应的发生,出水的碱度也下降。当停留时间足够时,水气比对水中溶解氧的浓度影响不大,较低的有机物浓度成为微生物降解活动的限制因素。经过生物接触氧化处理后的污水的腐蚀速率反而升高,体现出微生物的腐蚀作用和硝化反应的作用。     

渤海西部局地大雾变化趋势及成因分析

利用2002-2012年秦皇岛地区4个气象站大雾监测及Micaps 3.0常规资料,对比分析卢龙与沿海站大雾的时空尺度分布特征,对大雾持续时间、日数进行跨月、跨年统计,从中筛选出189个样本个例进行变化趋势分析。对典型17个过程个例按能见度大小进行3级设定,对应其同步天气背景,分析大雾偏多的成因。     

新疆阿瓦提县废旧地膜回收利用研究

阿瓦提县地膜的过量使用使当地土壤环境逐渐恶化,严重污染了农村环境,并影响了农机作业质量的提高。通过分析2011年阿瓦提县地膜使用相关数据及地膜回收利用情况,提出了阿瓦提县地膜回收利用的优化对策:加大对"白色污染"危害性的宣传,提升广大农民群众的生态文明意识;发展废旧地膜回收利用企业,拓宽回收渠道;制定优惠政策,加大支持力度,促进废旧地膜回收利用;从农艺上防治和减少地膜残留;采取人工和机械回收相结合的措施,加大残留地膜回收力度。     

Optimization of the recovery of plastics for recycling by density media separation cyclones

Material recovery processes are presented as the optimum option for recycling plastic wastes as a means of recovering hydrocarbon resources. There exist a large variety of automated material recovery processes for recycling of such wastes but each with significant limitations. Of these, the separation based on differences in densities is advocated as the optimum process either for producing recycled products or preparing wastes for subsequent recovery processing.Density separation processes based on cyclone type density media separation (DMS) is presented as an important, potential method for increasing plastics recycling process capacities. It is demonstrated to have the capacity to separate a significantly larger range of particle sizes than those presently processed industrially. The mathematical relationship for the prediction of quality of typical LARCODEMS type density media separations by particle size and density as expressed by the Ecart Probable is presented.A proposed device configuration is presented for density media separation to optimize the recovery and purity of both density fractions produced. It is also suggested that to be economically viable, a large scale of operation is required for industrial plastics recycling operations recovering and producing a number of different plastics with a purity to be used as a substitute for virgin material.