Abstract |
The recovery, reuse and sale of materials from liquid effluents, or produced as a result of the treatment of liquid effluents is discussed. A critical review of literature up to date on product recovery in major water use industries is presented. The economical, technical and philosophical framework which determines the application of product recovery is presented wherever possible. This report does not cover water renovation for reuse and product recovery from solid wastes. However, an evaluation of the utilization and product recovery of municipal sludge is presented. The principal areas of discussion are waste reduction practices including in-plant control, recovery techniques and practices, practical operating problems and the relationship between recovery and treatment. It is concluded that product recovery is an accepted practice with increasing usage; industry needs increasingly complex processes to develop optimum recovery schemes; by-product recovery results in a net cost to industry generally of a smaller magnitude then conventional treatment; and the situation is complicated by the tax exemption laws. (Author) |