① Pollution sources of industrial wastewater. Including gas plants, oil refineries, chemical plants, dye plants, pulp mills, coking plants, electroplating plants, chlor-alkali plants, pesticide plant, glass factories, paint factories, synthetic resin factories, smelters, battery factories, paint factories and so on.
(2) industrial waste gas pollution sources. Including thermal power plants, steel mills, coking plants, non-ferrous metal smelters, petrochemical plants, nitrogen and phosphate fertilizer plants, sulfuric acid plants, chlor-alkali plants, chemical fiber plants, pesticide plant, synthetic rubber plants, paper mills, glass plants, cement plants and so on.
③ Pollution sources of industrial waste residue. Including mining slag in the construction of various metallic and nonmetallic mines, metallurgical slag in metallurgical industry, fuel slag in thermal power plants and boilers, chemical slag in chemical industry and waste residue in sugar, paper, ceramics and other industries;
④ Pollution sources of industrial noise. Including metal mining, power plants, metal smelters, cement plants, printing and paper mills, textile industry, machinery industry, casting and forging enterprises.
In recent ten years, Shenyang smelter has been closed, chemical and pharmaceutical enterprises have been relocated and reformed, and central heating has been provided. The environmental situation has been greatly improved. Now Shenyang has become a "forest" city and a national environmental protection standard city.
Of course, tomorrow will be better. Today, the task is very arduous.