Economic Aspects of the Recycling or Disposal of low-Value Organic Wastes

Abstract

(1) Object of Thesis. The objects of this thesis are: (a) to determine the economic conditions under which low -or marginal-value organic wastes may be (i) recycled, (ii) re-used for another purpose or (iii) disposed of; (b) to determine the viability of processes for recycling this category of waste in general, and the viability of certain microbiological processes developed at the Biodeterioration Information Centre of this University in particular; (c) to investigate the market and institutional factors governing the recycling and re-use of this waste and the obstacles to such recycling or re-use; (d) to discuss in some detail the problems associated with three important types of waste in this category, viz. municipal waste, sewage effluent and agricultural wastes, partly to illuminate the points mentioned above; (e) to attempt to relate the recycling of wastes to biological material cycles (a minor point). ( 2) Argument. The contention of this work is that (a) these low-value organic wastes create, on the one hand, various problems of disposal and are liable to give rise to various unpleasant spill overs if disposed-of unhygienically and constitute, on the other hand, a potential source for raw materials whose primary sources are under pressure or dwindling and which are becoming increasingly scarce; and (b) techniques can be and have been devised either to re-use this material or to dispose of it hygienically; the latter term meaning that refuse and other waste is disposed of at the minimum cost to the environment in general and to human society in particular. Which set of techniques is used for any particular waste will depend on the expected comparative net costs or benefits during the lifetime of the necessary investments; but it will be show that because of increasing pressure on primary resources and increasing rent payable to the controllers of the same, re-use as against disposal is becoming increasingly competitive. It will also be shown that there are still many technical (e.g. mixture of wastes, dilution, high bulk) and economic problems (e.g. institutional problems, relating output to expected size of market, inelasticity of supply) to be overcome before a satisfactory position is reached. (3) Method. This work is designed to argue from the general to the particular. It begins with a general introduction putting the topic and the thesis in its historical setting and which also attempts to define "wastes," discusses recycling patterns, relates the activity of the economy to that of the biosphere and introduces a distinction between recycling and re-use - important for wastes which often cannot be recycled into the primary resource stream. Energy problems are referred to, for completeness, (Chap.1) Macro-economic issues are then discussed, especially the increasing rent in the price of diminishing resources. This is followed by a discussion of various micro factors on the level of the firm or authority contemplating recycling - including the introduction of the principle of the non-mixture of wastes. The principles enunciated in previous chapters are then discussed with reference to the particular problems of household wastes, sewage effluent and farm wastes in that order; which chapters also attempt to explore the prospects of recycling those particular wastes and attempt to evaluate certain projects developed at the biodeterioration Information Centre ( Chapters 4,5 and 6),viz. the biodegradation of used newsprint by thermophilic fungi as investigated by Dr. T. G. Barnes (Ph.D, 1973) and the biodegradation of the solid fraction of farm animal wastes as investigated by Dr. K. Seal (Ph.D,1974).The final chapters summarise and conclude the argument and also discuss the limitations of economics when dealing with this type of problem. Mathematical expositions have been avoided, except where their use clarifies the argument. 4) Conclusions. (a) Increasing costs of primary resources mean that there is a good economic case for the re-use of biosphere wastes in general. b) There is a spectrum of use ability of these wastes -ranging from those already partly used (e.g. paper) to the un-useable (e.g. silage liquor). However, even in the case of those wastes that are already partly re-used, new institutions as well as new technologies are needed to exploit these materials. (c) These wastes can only be reclaimed if they are not allowed to become mixed indiscriminately. The purposeful combination of two or more materials, however, is permissible. (d) These wastes have limited potential value as an energy source. They have far more value as a materials source. (e) While it is possible to conclude favourably on the prospects for re-using municipal waste and to a certain extent farm wastes, it was not possible to give a final verdict on the viability of the Biodeterioration Centre processes mentioned above.