Resource Recovery and Conservation最新文献

A survey has been made of the sources, amounts and methods of disposal of major mining, industrial and municipal wastes and by-products available in the 48 conterminous states of the United States. This includes the present and potential uses of these wastes and by-products as construction materials.

While more than 3 × 10⁹ tons (Mg) of waste materials and byproducts are generated annually in the United States, only small amounts are being used by the construction industry. The low level of use does not yet reflect the advances being made in converting wastes into viable construction materials. In several cases, construction materials produced from wastes have been at least the technological equivalent of materials produced from virgin resources. Factors which are impeding the increased utilization of wastes are discussed, and emerging incentives which could facilitate their increased use are covered.

In dealing with the recycling of packaging materials, it is important that the issue is viewed in the right perspective and not isolated from the total context. Of special importance is the interlinking with traditional recycling activities and with planned mixed waste resource recovery plants. But first and foremost, the role of packaging as a means of effective distribution of goods with the inherent contribution to resource conservation should be recognized and taken into account.

Because recycling practices as well as packaging design and use are all in a dynamic stage of development, the adoption of legislative and administrative measures that tend to freeze the status quo should be avoided in order that the benefits of these developments can be reaped at all levels.

This paper reviews mechanical processes for the processing of municipal solid waste for the recovery of magnetic metals, aluminium, glass, paper and the conversion of separated organic materials into various forms of refuse-derived fuel. Where possible, the descriptions of the processes are related to the purity and form requirements of product specifications which are available or under development.

The planning and implementation of resource recovery from municipal solid waste are often uncertain. Six categories of risk associated with this are identified: (i) the quantity of waste available; (ii) the composition of the waste; (iii) the ability of the equipment to operate to specification; (iv) the ability to meet product specifications; (v) the ability to sell the recovered products; and (vi) the uncertainty of having to meet future (hence unforeseen) environmental regulations. Each of these is defined and possible approaches to manage them described. In addition, the economic risk of resource recovery is discussed in terms of future projected and relative costs of recovery and revenues from the sale of the energy product. Because of differences in inflation rates between operation costs and energy product revenues (at a level rate of amortization), it is,shown that at some future time the cost of recovery is less than alternative disposal.

If industry is going to invest in material and/or energy recovery schemes, they must be economically attractive. This may either be measured directly when recovery is on a sound commercial basis, or there has to be some sort of fiscal incentive to make the schemes appear attractive.

The types of packaging material considered are plastics, paper, glass and metal. These may be directly recycled, converted into another useful product, or the combustible portion converted to a fuel. The problem is introduced, its size and variabilities are presented, and this is followed by consideration of each material in turn so as to identify the size and scope of the problem.

This paper indicates and clarifies a number of basic elements in waste treatment operations. These are mostly specific for the Netherlands. Therefore, the introduction of new approaches or new processes for waste treatment should be considered in this specific context. Some emphasis is put on energy-related aspects because of a growing concern for the energy supply of the Western world. It is common practice to consider municipal solid waste as an energy carrier and, therefore, as an alternative for the usual sources of energy. Finally, an indication is given about the marketability of products from waste.

This paper describes the history of environmental policy in the Common Market of Europe and its influence on the national policy of the nine member states. Also included is a survey of the environmental policy in the OECD, particularly in the field of waste management. Illustrated are the reasons for stagnation in the preparation of an environmental policy for packaging. A new plan of work should be drawn up based on the European Commission (EC) action programme on the environment and the action programme on packaging (given in the appendix), but now paying more attention to strict procedures. In pursuit of environmental interests, re-utilization and the prevention of the generation of waste should be taken into account when preparing Common Market policies in other fields. An integrated approach is suggested for packaging. For instance, with the EC Directives on labelling, prepackaging according to volume for certain liquids, price indication, etc., it is possible to reach environmental aims.

Some result of Dutch experience with sorting at the source are given to dispel frequently held views that this method of recovery does not assure a stable source of material or that the voluntary cooperation of citizens is not possible.