Resource Recouery and Conservation, 1(1975) 115-127 115 o Eisevier Scientific Publishing Company, Amsterdam - Printed in The Netherlands THE RCONOMfCS OF RECOVERY OF MATERIALS FROM INDUSTRIAL WASTE -- A CASE STUDY A.V. BRIDGWATER Department of Chemical Engineering, University of Aston in Birmingham, Birmingham B4 7ET (England) (Received 23rd September 1974) ABSTRACT Millions of pounds worth of vaIuaMe materials are discarded every year in industrial wastes. While there are well established recycling patterns for some materials, most are lost because contamination, dilution, or scale of operation makes recovery uneconamioal. The pm&ems and possibilities of recovering vaiuable mate&& from liquid and liquid- solid indu&riai w&es are outiined by reference to evaluations made in several case studies. In particular, an examination is made of wastes removed by R West MkHanda dii contractor over a twelve month period. The ways in which these wastes am deaIt with at present by surface and subsurface disposai are discussed along with the haxards and safety factors inherent in such operations. The examination shows that in the wastes disposed of the most potentially valuable materials to recover were hydrochloric raid and zinc. The relationship between recovery and dumping is discussed and future trends suggested. This shows that recovery of more materinls shouid be undertaken, perhaps as a govern- mentaI services and that the advantages of economy of seaie must be utilised, by combining wastes from several sources. INTRODUCTION The accepted method of disposal of domestic wastes in the Middle Ages was discharge through the window or door into the street. This practice generally has been supplanted by collection systems for solid wastes, and a separate conveyancing system for liquid and semi-liquid wastes to a central treatment point. Because of the lack of governmental controls, industry still continues to employ the mediaeval technique for some of its obnoxious and toxic wastes. This paper is concerned only with liquid and liquid-solid chemical wastes from industrial processes. Generally these are either treated where they are produced with varying degrees of recycling or are disposed of by dumping. Recycling is already widely practiced by many industries and many examples have been pub&he& In some in&ancess, however, q&X&&k3s of waste produced are too mall to be economically reey&d, or the company is unaware of the recycling possibility and the waste is removed by a disposal