Relating disposal-based solid waste reduction rates to recycling rates

Some states measure progress in their waste reduction programs on the basis of recycling rates, while others use disposal-based reduction rates. It is generally recognized that these two measures are conceptually distinct. Nevertheless, when informational surveys of waste reduction activities are compiled, the data are usually combined in a manner that blurs this distinction and complicates the issues involved. In this paper, these two concepts are defined in a precise manner and equations are derived which clearly depict the relationship between recycling rates and disposal-based reduction rates. Information from a national survey and the US Environmental Protection Agency is used to illustrate the concepts which are developed in the paper.     

Environmental assessment of packaging: The consumer point of view

When marketing environmentally responsible packaged products, the producer is confronted with consumer beliefs concerning the environmental friendliness of packaging materials. When making environmentally conscious packaging decisions, these consumer beliefs should be taken into account alongside the technical guidelines. Dutch consumer perceptions of the environmental friendliness of packaged products are reported and compared with the results of a life-cycle analysis assessment. It is shown that consumers judge environmental friendliness mainly from material and returnability. Furthermore, the consumer perception of the environmental friendliness of packaging material is based on the postconsumption waste, whereas the environmental effects of production are ignored. From the consumer beliefs concerning environmental friendliness implications are deduced for packaging policy and for environmental policy.     

军民协调灾害卫生救援体制的情报与模式研究

通过对国内外军民协调灾害卫生救援体制现状的对比分析，找出我国现行灾害卫生救援体制与国外体制之间的差距，分析了产生差距的原因．在此基础上，从加强军民协调、平战结合角度，提出我国灾害卫生救援体制四种框架模式，运用专家咨询法与层次分析法相结合的方法进行综合评估。明确了我国军民协调灾害卫生救援体制发展的战略目标和近中期目标，从而提出加强我国军民协调灾害卫生救援体制建设的对策与建议．     

Recent trends in recycling activities and waste management in Japan

Japan's basic approach to municipal solid waste (MSW) is (1) waste reduction, (2) promotion of recycling, (3) volume reduction by intermediate treatment, and (4) environmentally sound final disposal. A brief history of legislative trends in waste management is given as background for current waste management and recycling activities. The material recovery rate for MSW collected by local municipalities was only 5.6% in 1996. More than half of MSW, on a volume basis, consists of containers and packages, while great amounts of landfill space are also taken up by bulky wastes such as electric appliances. Therefore, in order to promote recycling and decrease landfill waste, Japan is targeting containers, packages, and electric appliances. A law promoting separate collection and recycling of containers and packages (Packaging Waste Recycling Law) and a law requiring the recycling of specific home electric appliances into new products (Home Electric Appliance Recycling Law) were introduced in June 1995 and June 1998, respectively. These laws are in line with the OECD policy Extended Producer Responsibility (EPR). Received: September 16, 1998 / Accepted: March 10, 1999     

射流气浮技术在发生炉煤气洗涤废水封闭循环处理中的应用

本文介绍了采用混凝－射流高速气流法处理煤气洗涤循环废水的技术及在工程中的应用。该地煤气洗涤废水焦洗洗去除率为４０－８０％,悬浮和去除率为８０－９５％,挥发酚八方经为１０％,较好地满足了发生炉煤所洗涤废水循环回用的水质要求。     

Development of a catalytic cracking process for converting waste plastics to petrochemicals

The catalytic degradation of polyolefin using H-gallosilicates was examined using a bench-scale reactor (0.8kg/h) with semicontinuous feeding and the following plastics: (1) low-density polyethylene (LDPE) pellets; (2) linear low-density polyethylene (L-LDPE) pellets; (3) high-density polyethylene (HDPE) pellets; (4) polypropylene (PP) pellets; (5) polyolefin obtained from pulverized industrial waste plastics. The yields of liquid compounds from these materials, which were aromatics in most cases, ranged from 55wt% to 68wt%. With an increase in the ratio of total reactant to catalyst, the liquid yield remained the same. Yields of benzene, toluene, and xylenes (BTXs) decreased rapidly to below 50wt% at a ratio of more than 30. Differences in this ratio for BTXs were always small and were independent of the material. Only about half of the gas product was propane with a fresh catalyst. When the experiments were repeated, propylene, isobutane, and isobutene were found to increase.     

Waste plastics recycling process using coke ovens

The Japan Iron and Steel Federation (JISF), as its voluntary energy-saving action plan, proposed a 10% energy reduction by 2010 with 1990 as the basis. Further, it has suggested an additional 1.5% energy saving by the use of waste plastics as a metallurgical raw material. The amount of processing of waste plastics which corresponds to this amount of energy conversion is about 1 million t scale during 1 year. Conventional known methods for recycle-processing of waste plastics include, for example, the method of injection into a blast furnace to use waste plastics as an iron-ore reducing agent instead of coal. On the other hand, the coking process is considered to be suitable as a waste plastic recycling facility because the process involves coal carbonization in a high-temperature and reducing atmosphere. Carbonization tests with mixed waste plastics were conducted with laboratory equipment and in actual coke ovens. As a result, it was confirmed that the waste plastics recycling process using coke ovens is feasible. Therefore, a waste plastics recycling process using coke ovens was started as a chemical recycling technology at Nippon Steel.     

中国的污水处理与水环境管理政策

中国已建有420座污水处理厂,城市污水处理率达30％以上。但污水处理任务仍很艰巨,必须采取加强工业污染防治,建设大批新的污水处理厂和控制面源污染等对策。     

Korea's policy instruments for waste minimization

This paper considers the current status of waste generation and waste treatment trends, and introduces a wide variety of policy instruments for waste minimization at every stage of economic activity in Korea, i.e., production, distribution, and consumption. At each stage, the Korean government has imposed a policy mix of direct regulations and economic incentives. These policy instruments have made definite contributions to a reduction of waste generation and an increase in the recycling rate. Despite these fruitful outcomes, there are still some shortcomings with respect to efficiency and equity. Among other aspects, this paper examines three representative economic incentives – the charge system, the volume-based-collection fee system, and the deposit–refund system – and identifies shortcomings in each. Some suggestions are made for the creation of better systems of economic incentives. However, many experts insist that this kind of piecemeal change in each policy instrument is not enough to achieve the ultimate goal of resource circulation and an environmentally friendly society, especially in Korea, which is a country with little land, a high population density, and a high economic growth rate. Among experts, special emphasis is placed on the activation of recycling industries to achieve these goals. Received: April 2, 2001 / Accepted: September 10, 2001     

The city of San José's integrated waste management program: a case study for reaching high levels of diversion

The city of San José, California, USA, has a widely recognized integrated waste management program and is currently diverting close to 50% of its waste stream from landfill disposal. This paper describes the residential and commercial components of the city's waste management program. Information is presented on performance (e.g., types and quantities of materials that are collected, processed, and disposed of), customer service, and costs associated with the program. Received: October 4, 2000 / Accepted: February 15, 2001