The effects on waste reduction and recycling rates when different components of the waste stream are counted

States differ in the components or solid waste management activities which they include when determining solid waste reduction and recycling rates. Thus, when attempting to draw comparisons among states, confusion arises in two ways: (1) use of two types of rates; and (2) use of different components or activities when calculating a given rate. This paper presents a mathematical basis for understanding the impacts on rate calculations when variations occur in the components and activities included in those calculations. Estimates of the incremental changes occurring in the rate calculations when incineration or selected components such as yard waste, construction and demolition wastes, and junked automobiles, are added to a base of municipal solid waste constituents are found using national data. Finally, the achieved rates reported by states counting different combinations are compared.     

Environmental Management of Human Waste Disposal for Recreational Boating Activities

/ A methodology to estimate the number of pump-out facilities and dump stations required to service human waste disposal for recreational power boating activities in Pennsylvania during the 1994 boating season is described. Study results suggest that a total of 39 additional pump-out stations and 13 dump stations may be required on seven major waterbodies: The Three Rivers Area, Lake Erie/Presque Isle Bay, Raystown Lake, the Susquehanna River, the Delaware River, Lake Wallenpaupack, and the Kinzua Reservoir. Suggestions for improving the methodology are provided. KEY WORDS: Human waste; Recreation; Power boating; Waste facilities; Waste disposal; Pennsylvania     

Public participation in plastics recycling schemes

Without public contributions, recycling from domestic waste would not be possible. In order to support recycling projects it is important to try to understand who recycles, how they recycle, and why they recycle. This paper presents the results of a structured survey of 500 members of the public served by schemes to collect plastics waste for recycling. Data were gathered on the characteristics, behaviours and motivations of recyclers. The authors also sought to discover how the public perceive plastics compared to other materials, and as a recyclable material. Responses were collected in such a way that the awareness of the recyclability of materials could be compared with the recycling behaviour of respondents. An element of comparison was introduced between those served by a system of bottle banks (bring scheme) and those covered by a household collection (collect scheme). The survey results are reported and their implications for the management of post-consumer plastics waste collection schemes are discussed.     

石化废水深度处理回用工艺设计

化工废水中含有机物、烃类、石油类、重金属等有毒有害物质,成分复杂,难于生物降解,并且对微生物代谢产生抑制和毒害作用.文章通过研究石化废水二级生化处理后回用的工艺技术,提出以絮凝、氧化、膜分离等组合工艺为主体的石化废水深度处理流程,并对设计参数、工艺调试进行优化分析,为石化废水处理回用开辟途径.     

超声清洗MBR生物膜--臭氧化技术在中水回用中的应用

超声清洗MBR生物膜-臭氧化技术,是在传统的二级生化污水处理技术的基础上,采用膜生物技术、臭氧化工艺和现代超声波清洗膜元件技术,进行生活污水回用处理的新兴技术.膜生物(MBR)技术具有出水水质好,一次性投资低,占地面积小,运行费用低等优点;利用现代超声波技术清洗膜元件,既可以彻底清除粘附在膜内、外壁上的污染物,又可以避免化学清洗对膜造成的危害,及清洗剂对环境的污染;采用臭氧化工艺,利用臭氧的强氧化性,可以彻底消除细菌、臭味、色度等可能对回用人群造成的危害,使处理后的水成为真正安全的回用水.     

Laboratory scale studies on removal of chromium from industrial wastes

Chromium being one of the major toxic pollutants is discharged from electroplating and chrome tanning processes and is also found in the effluents of dyes,paint pigments,manufacturing units etc.Chromium exists in aqueous systems in both trivalent(Cr^3 )and hexavalent (Cr^6 )forms.The hexavalent form is carcinogenic and toxic to aquatic life,whereas Cr^3 is however comparatively less toxic.This study was undertaken to investigate the total chromium removal from industial effluents by chemical means in order to achieve the Pakistan NEQS level of 1 mg/L by the methods of reduction and precipitation.The study was conducted in four phase Ⅰ,the optimum pH and cost effective reducing agent among the four popular commercial chemicals was selected.As a result,pH of 2 was found to be most suitable and sodium meta bisulfate was found to be the most cost effective reducing agent respectively.Phase Ⅱ showed that lower dose of sodium meta hisulfate was sufficient to obtain 100% efficiency in reducing Cr^6 to Cr^3 ,and it was noted that reaction time had no significance in the whole process.A design curve for reduction process was established which can act as a tool for treatment of industrial effluents.Phase Ⅲ studies indicated the best pH was 8.5 for precipitation of Cr^3 to chromium hydroxide by using lime.An efficiency of 100% was achievable and a settling time of 30 minutes produced clear effluent.Finally in Phase Ⅳ actual waste samples from chrome tanning and electroplating industries,when precipitated at pH of 12 gave 100% efficiency at a settling time of 30 minutes and confirmed that chemical means of reduction and precipitation is a feasible and viable solution for treating chromium wastes from industries.     

利用水泥回转窑焚烧处置危险废物的评价研究

根据对北京水泥厂焚烧处置危险废物的实验，以大量数据为基础，分析研究油漆渣、丙烯酸树脂渣和有机废液在掺入水泥生料中一起焚烧处置的可行性，经实验监测和与一般废物焚烧炉比较，得出使用水泥厂回转窑焚烧处置废物无论在技术上、经济上还是在环境要求上都是可行的，为工业固体废物的焚烧处置提供了一种新途径。     

香港的有害废物管理动向

为了给都市型地区的有害废物管理工作以借鉴，本文详细介绍了香港地区近１０年通过建立有害废物立法管理，制订污染控制总体规划，强化政府对有害废物的有效管理手段，以及近期和今后的主要管理措施的发展动态。     

流动注射-分光光度法测定工业废水中的Fe^2＋和Fe^3＋

将Fe^2 与邻菲啰啉的显色反应引入流动注射系统，用盐酸羟胺将Fe^3 预先还原，0～6μg/ml的Fe^2符合比耳定律，检测出限0．11μg／ml。0．25μg／mlFe^2 经5次测定的标准偏差为2．2％，进样频率为120次／h，回收率98．5～104％。对工业废水中铁的测定取得了满意的效果。     

Comparative evaluation of processes for heavy metal removal from municipal solid waste incineration fly ash

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