Energy Conservation and Fuel Production by Processing Solid Wastes

Abstract

Disposal of municipal solid wastes may result in needless environmental damage and loss or degradation of land. In addition, the material and fuel resources contained in the wastes remain unused. The extents of these latter in the entire United States are estimated in this paper.New terms are introduced to aid more precise estimation than hitherto of the amount of energy which can be conserved through processing and recovering the resources in municipal solid waste. Further, the likely rate of implementation of resource recovery in the U.S. is predicted on the basis of a simple model which relies on the assumption that the rate of implementation is proportional to the number of plants that are or will be actually on-line.There is a great temptation to combine the rate of implementation with the sum of the energy potentially recoverable from the various sources of wastes, and to convert the answer to, for example, so many barrels of oil per day. As is indicated in the discussion, this exercise in not technically justified. Nonetheless, the energy that is potentially recoverable from solid wastes has an arithmetic equivalence of the order of magnitude of 1 million barrels of oil per day (1.6 × 106 m3, or 158 × 106 litres) in the United States alone, and even more if a generous fraction of agricultural and crop residues could be garnered for processing. This order of magnitude, perhaps as much as substitution equivalence, should be compared with the stated U.S. goal of conservation of 2 million barrels of oil per day (presumably also an arithmetic equivalence) from all sources by the end of 1977—not just from solid wastes (Ford, 1975).The analogy of solid waste as an ‘urban ore’ has been used to the point of almost becoming trite. Nevertheless it may well be timely to extend the analogy to waste as an urban oil-well or coal-mine.