Urban refuse is the only renewable resource that is capable of supplying a significant part of the growing U.S. demand for minerals and energy. Viable processes in the United States and other highly industrialized countries follow a typical pattern of transferring valuable constituents from host materials of natural origin to consumer goods and energy materials. Most of these valuable constituents, not totally consumed, are thus concentrated in two places: in the large reservoir of goods in use and in the discarded goods and daily urban wastes of the total society. Municipal refuse contains huge quantities of recoverable minerals and organic materials of great total value. The ultimate practice of recovering and recycling such values will not only increase domestic supplies of needed minerals and energy raw materials, but it will also offer a solution to many waste disposal problems of current critical importance. The municipal resource known in the federal Bureau of Mines as "urban ore" is, by comparison with its natural counterpart, rich in grade, has a variety of values, and is relatively simple to process. These materials, formerly considered to be a great liability, appear destined to become a great national asset. A number of recovery processes have been developed and tested through the pilot plant scale, and some are scheduled for full-scale demonstrations in the immediate future. These events indicate a strong trend toward optimum recovery of values from wastes wherever possible. The practice will undoubtedly become commonplace within the decade.
Umschau in Wissenschaft Und Technik (Germany), Heft 12, June 1973, PP. 364-369