R&D, sales and installation of water treatment equipment; Construction of seawater desalination project; Sewage treatment; Water conservancy project design and construction; Environmental detection and treatment; Air pollution control; Recycling of waste materials (excluding hazardous chemicals and Class I precursor chemicals); Technology development and transfer of environmental protection products; Sales, installation and maintenance of energy-saving equipment; Wholesale and retail: Computers, electronic products, industrial automation equipment, desalination equipment, water treatment equipment, electrical appliances, instrumentation, electronic equipment, hardware, electromechanical equipment, steel, chemical products (excluding hazardous chemicals and Class I precursor chemicals); Operating other general business items that can be operated without administrative approval. (Projects that must be approved according to law can only be operated after being approved by relevant departments)