Research, development, manufacturing, sales, and installation of environmental protection equipment, sanitation machinery, wastewater treatment equipment, waste compression equipment, waste treatment equipment, intelligent prefabricated toilets, and electromechanical equipment; research, sales, and technology transfer of sanitation vehicles; purification treatment of wastewater, sludge, and odors; technical application of exhaust gas dust removal and desulfurization; construction and technical development and transfer of environmental protection projects; collection and transportation of municipal solid waste; road sweeping services; sales of steel, non-ferrous metals, and ferrous metals.