Applicability of a Septic Tank/Engineered Wetland Coupled System in the Treatment and Recycling of Wastewater from a Small Community

A septic tank (ST)/engineered wetland coupled system used to treat and recycle wastewater from a small community in Dar es Salaam, Tanzania was monitored to assess its performance. The engineered wetland system (EWS) had two parallel units each with two serial beds packed with different sizes of media and vegetated differently. The larger-sized medium bed was upstream and was planted with Phragmites (reeds) and the smaller-sized medium bed was downstream and was planted with Typha (cattails). The ST/EWS coupled system was able to remove ammonia by an average of 60%, nitrate by 71%, sulfate by 55%, chemical oxygen demand by 91%, and fecal coliform as well as total coliform by almost 100%. The effluent from the ST/EWS coupled system is used for irrigation. Notably, users of the recycled irrigation water do not harbor any negative feelings about it. This study demonstrates that it is possible to treat and recycle domestic wastewater using ST/EWS coupled systems. The study also brings attention to the fact that an ST/EWS coupled system has operation and maintenance (O&M) needs that must be fulfilled for its effectiveness and acceptability. These include removal of unwanted weeds, harvesting of wetland plants when the EWS becomes unappealingly bushy, and routine repair.     

倡导循环经济追求持续发展

分析了“资源-产品-污染排放”给人类带来的非持续发展后果,综述了其对物质循环动态平衡的影响,提出保持物质循环动态平衡是循环经济的途径之一,“资源-产品-再生资源”模式是实现物质循环动态平衡的途径,也是对可持续发展的一种支持。     

底泥生物与化学需氧动力学模式的探讨

提出了底泥生物和化学需氯的动力学模式，并用生物抑制试验对该模式进行了验证。结果表明：静止和完全混合状态下，底泥的生物需氧过程符合Lawrence McCarty模式。静止状态下，底泥的化学需氧过程可以用一级反应动力学来描述：而完全混合条件下，则可用零级反应动力学表示。底泥性质和扰动程度是影响底泥需氯的重要因素。     

城市污水回用于循环冷却水的探讨

对国内外城市污水回用循环冷却水的实践进行了详述，针对国内城市污水水质，推荐污水水质回用标准，并确立相应的工艺流程，期间还讨论了城市二级处理污水回用时要注意的问题。     

糖厂酒精废醪液资源化实例

连续运行3个榨季表明采用资源化治理技术"三废",废水和废气达标排放,将原来的污染物全部转化为微生物肥.‘‘资源化治理糖厂污染是一项具有环境效益、社会效益和经济效益的技术.     

产品再回收设计的经济性分析

研究表明，产品性能的70％～80％是由设计阶段决定的，而设计本身的成本仅为产品总成本的10％，因此考虑当前环境效益和经济效益的共同要求，企业开展产品的绿色设计是十分必要的。立足于产品的绿色设计，构建了产品再回收设计的经济性分析模型，以保证产品在回收处理阶段的成本与收益之间的均衡。     

废旧电脑设备的资源化研究

随着人口的增长,固体废物对于环境的污染越来越大,而科学技术的飞速发展,导致了电脑设备更新换代越来越快.本文分析了废旧电脑设备的环境危害和主要特点,资源化回收利用方法和回收程序,对比分析不同国家对待废旧电脑设备所采取的政策,然后详细介绍了我国废旧电脑设备管理与回收利用对策,其根本解决对策是加强立法、强化管理、健全回收网络和依靠科技进步.     

废旧电器再生利用产业技术、经济和社会循环互动机制探析

废旧电器回收再生利用是开辟“城市矿山”的资源源泉。从技术、经济、社会三个层面分析其物质、价值和行为三个形态的循环机理及其互动关系，价值循环要考虑自然资源资本和环境保护与恢复的成本来分析其价值保值与增值过程；行为循环要以基于生产者责任延伸制的主体责任体系为纽带，分析其行为活动规律及其相互关系；物质循环要按照循环经济的原则考虑各种物质形态的有效转换与有机联系，以实现资源到资源的物质闭路循环。     

A review of sediment predictive techniques as viewed from the perspective of nonpoint pollution management

User-oriented criteria for the evaluation of physically based management models are presented. These criteria emphasize the utility rather than the elegance of the model. The standards are then applied to efforts at predicting non-point pollutant loadings. In particular a critical review of sediment pollution is used as the basis for the evaluation of sediment yield models as management tools. A wide range of sediment yield models are rated and recommendations for their use are made.     

我国电子废弃物管理与资源化对策

电子废弃物对人类环境的影响,已成为全球化的问题.通过对发达国家关于电子废弃物管理以及资源化技术的进展回顾,针对我国目前的情况提出相应的对策：制定延伸生产者责任以及有害物质的停用限期的相应法规;建立电子废弃物回收网络体系;通过国家政策和经济的扶持,尽快建立专门处理电子废弃物的机构;加快我国电子废弃物处理技术的步伐,尽快提高现有工艺及设备.