The main subject of the Workshop was the new developments about the cost effective treatment techniques for better removal efftciencies and dis cussion of policies for pollution control. Although effluent water quality requirements differ from one country to another, their application will be an efficient mean for water pollution control. Specific promotion should be provided for polluters to meet the effluent water quality requirements. Results of pilot scale studies demonstrate the applicability of and ad vantages of sequenching batch reactor technology for pretreatment of in dustrial wastewaters Fixed film biological reactors offer the possibility to enrich slow growing specialized microorganisms by developing biofilms on support materials. Physical chemical processes are used for the treatment of unusual and difficult industrial wastewaters and membrane technologies for the con centration and recovery of raw materials and by-products, in industries where the conventional treatment technologies are inappropriate or uneco nomic~ Physical chemical processes give higher efficiencies when polymers are applied but the composition of these long chain chemicals is an im portant consideration; Most developing countries suffer from severe environmental problems and shortage of energy and resources. These countries urgently need simple, inexpensive and integrated environmental protection system, which combine wastewater treatment with recovery and reuse. Anaerobic treatment offer many advantages in this respect. Because recovery of substances from wastes serves twofold purpose of recyle and pollution control, it must be applied where possible.
