膜生物反应器在废水处理中的研究现状

膜生物反应器(MBR)是将生物处理技术和膜分离技术相结合的一种新型水处理技术。膜生物反应器具有常规废水处理工艺无法比拟的优势,本文介绍了膜生物反应器的分类、最新组合工艺及其在废水处理中的应用,并详细介绍了膜生物反应器存在的问题以及发展的前景。     

Simulating the temporal pattern of waste production in farmed gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax) and Atlantic bluefin tuna (Thunnus thynnus)

Most fish farming waste output models provide gross waste rates as a function of stocked or produced biomass for a year or total culture cycle, but without contemplating the temporality of the discharges. This work aims to ascertain the temporal pattern of waste loads by coupling available growth and waste production models and developing simulation under real production rearing conditions, considering the overlapping of batches and management of stocks for three widely cultured species in the Mediterranean Sea: gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax) and Atlantic bluefin tuna (Thunnus thynnus). For a similar annual biomass production, the simulations showed that waste output and temporal dumping patterns differ between the three species as a result of the disparities in growth velocity, nutrient digestibility, maintenance metabolic budget and husbandry. The simulations allowed the temporal patterns including the periods of maximum discharge and the dissolved and particulate nitrogen and phosphorus content in the wastes released to be determined, both of which were seen to be species-specific.     

Sustainable Mining in the European Union: The Legislative Aspect

This paper is a review of the community legislation of the European Union (acquis communautaire) with regard to the mineral extractive industry. It highlights the existing inconsistencies of the acquis, which require correction. Historically, the mining industry has received privileged treatment within the European Community. The treaties declare the promotion of a policy of using natural resources prudently and rationally to avoid their unconsidered exhaustion. However, mining is excluded from the scope of major environmental directives or reserves a certain freedom for interpretation. This has led to an increasing number of related cases at the European Court of Justice.The regulatory tools of the environmental acquis are rather diverse in controlling the emission sources, the pollution pathways, and the impacted receptor media through administrative measures or assigning environmental quality targets. A combined approach is needed for controlling the environmental impacts of the extractive industries. The amendment of the Seveso II Directive, the elaboration of a reference document on best available techniques and the preparation of a wide-scope directive on mining waste management might provide a frame for the elimination of the above discrepancies. In addition, a coherent European Community policy based on the balanced consideration of economic, environmental, and social aspects could ensure a sustainable development of the mining industry. National expert detached from the Hungarian Geological Survey, H-1143 Budapest, Stefánia út 14.     

Cleaner production in the ammonia-soda industry: an ecological and economic study

Five methods to reduce the negative influence of soda ash factories on the natural environment are presented: 1. obtaining calcium-magnesium phosphates by treating the suspension from raw brine purification with orthophosphoric acid (H(3)PO(4)), 2. production of precipitated chalk from soda processing waste, 3. production of gypsum and semi-brine, 4. desulphurisation of fume gases from the factory power plant, 5. utilization of distiller waste. The tests, accomplished on a laboratory scale, showed the high efficiency of these methods. Economic analysis has proved that only four out of the five presented processes can have a positive financial effect on soda ash factories, as well as being well justified economically. The value of two of the innovations presented is confirmed by their implementation in factories.     

Industrial waste management simulation game and its educational effect

The purposes of this study were to develop the Industrial Waste Game and to examine the validity of this game as a tool for environmental education. The aim of this game is to enable players to understand the social dilemma between individual interest of hazardous dumping and the social cost of purifying pollution, and to find a solution to the social dilemma by providing the monitoring and sanction system for illegal dumping or other efficient systems. The game was played by 213 undergraduate students who were divided into 40 groups of 5 to 6 people. One of 4 combinations of monitoring and penalty conditions was assigned to each group. The players were asked to answer questionnaires concerning their interests and understanding of the industrial waste issue before and after the game to evaluate educational effects. The results indicated that the players increased their awareness of industrial waste problems and came to understand that these problems were caused not by psychological factors such as immorality of the illegal dumper but mainly by social structural factors like the social dilemma. Through playing the game and participating in post-game discussion, players were able to obtain interesting experience and gain motivation to learn more.     

The copper cycles of European countries

A comprehensive technological copper cycle treating a series of life stages (mining and processing, fabrication, utilization, and end of life) has been constructed for sixteen countries on the European continent for the year 1994. In this paper we draw on that information to present country-level copper cycles for a sampling of the countries. We then compare the countries on the basis of their relative and absolute copper production, import/export, usage, recycling, and losses to the environment, and go on to produce per capita assessments of flow and stock changes. Among the results of particular interest are: (1) country-level copper budgets possess features often different from the continental budgets of which they are a part. For example, Europe extracted only slightly more copper from mines than it deposited in landfills, while the mine to landfill flow ratio was about 11:1 in Poland and near zero in the United Kingdom; (2) Germany led all other countries in the group of sixteen in the absolute magnitude of every major copper flow (production, import, export, consumption, and waste generation, and in per capita flows of copper entering use and waste management), while the Benelux countries led all others in per capita flows for all other categories; (3) citizens of essentially all the countries discarded 1–3 kg Cu/year, mostly in obsolete electronics and end-of-life vehicles.     

Minimising waste in the food and drink sector: using the business club approach to facilitate training and organisational development

The aim of the East Anglian Waste Minimisation in the Food And Drink Industry Project was to develop waste minimisation capability in food and drink sector companies by providing a structured training programme and consultancy support to participating members of a business club. The business club forum provided the structure within which interactive training and development sessions were delivered. Expertise and assistance in implementing waste minimisation and waste management programmes was given to member companies at their sites.The project resulted in pound 1,800,000 per annum of identified savings with pound 1,100,000 of verified savings already achieved. Training and development contributed fundamentally to these project outcomes and achievements.The structured training package used three different approaches or methods. Teaching and workshop sessions were used to present interactive training on waste minimisation practice. These were supplemented by interactive 'report-back' sessions where the 'project champions' presented progress reports to the club on waste minimisation at their sites.An overview of the business club approach is described, together with an account of the successes and challenges of applying a structured training and development programme and the barriers to waste minimisation that were overcome. Training effectiveness was measured according to reaction, learning, application and impact.     

Analysis of Socioeconomic and Environmental Impacts of Waste Stabilization Pond and Unrestricted Wastewater Irrigation: Interface with Maintenance

The effluent from the waste stabilization ponds (WSPs) of the University of Nigeria, Nsukka Campus, is used for irrigation by poor rural farmers. There has been fear that the poorly maintained WSPs and the reuse practices are contributing to environmental degradation and health hazards. In this study the environmental and socioeconomic impacts of the WSPs and reuse were evaluated based on data collected from questionnaires and the literature. The engineering and agricultural properties of soil in the irrigated and nonirrigated areas were compared. Comparison of the health status of the farmers and nonfarmers, of consumers of crops irrigated with wastewater and nonconsumers was performed using Student's t test and the z-score test. The occurrences of diarrhea, typhoid fever, and malaria among the various groups were used as indices. Analyses show that the health status of the farmers and consumers is poorer than those of nonfarmers and nonconsumers at the 5% level of significance. Vegetable cultivation using WSP effluent is a means of sustenance to the farmers and provides an affordable means of satisfying their nutritional deficiencies. However, the poorly maintained WSPs create odor and mosquito nuisances, trap and destroy livestock, and flood nearby compounds with waste debris. At both 1% and 5% levels of significance, communities around the ponds (< 300 m) suffer malaria more frequently than those who live far away (> or = 300 m). Cost-benefit analysis argues in favor of improvement of WSP management and irrigation reuse of wastewater. Dredging of the ponds, training workers and farmers, and adopting appropriate maintenance and monitoring strategies will greatly enhance the socioeconomic status of the urban poor farmers.     

Waste minimization study in a solvent-based paint manufacturing plant

Solvent-based paint manufacturing plants produce significant quantities of hazardous waste, which must be properly treated before it can be disposed. Since the cost for treating this waste is high, reducing the quantity of waste has become a crucial issue in this industry.Waste minimization options are beneficial for the owner of the plant as well as for the environment. The quantity of hazardous waste can be minimized by changing the plant's technology or by substituting hazardous substances, which are used in the paint manufacturing process, with environmentally friendly ones. Furthermore, separating the various waste streams makes it easier to recover raw materials and enhances the possibility of their reuse within the production process. This will decrease operational costs for the plant.This paper presents a case study of waste minimization in a solvent-based paint manufacturing plant. Source reduction, recovery, and recycling methods are taken into consideration. Its aim is to develop an understanding of the facility's waste generating processes, to suggest ways to reduce the waste production, and finally to select an appropriate waste minimization option to suggest to the plant. Some of the suggested methods are currently being practiced while others are at initial stage of development.     

An economic modelling approach to the design and delivery of sustainable waste minimisation clubs: Prospects in the new policy framework

Since the early 1990s, waste minimisation clubs have been important sources of information for industry in the UK on clean technology and sustainable waste management practice. Despite this contribution, concern has grown about the declining number of clubs, their performance and the likelihood that they will continue to play a key role in national policy.This paper examines the evidence available and provides estimates of how the numbers varied in England since the first clubs were formed. The results presented indicate that, after initial expansion, numbers went into decline. The paper then explores, using economic theory, why this pattern should have developed and suggests it to be a function of how clubs were designed and managed. The results of the analysis are used to propose alterations in how future clubs could be designed so that they continue to contribute effectively to the development of sustainable waste management in UK industry. These lessons are of value to policy in both the UK and other countries considering the development of this important tool of waste strategy. The paper concludes with a number of suggestions for future research.