China Hongqiao has developed a sophisticated system to implement its environmental protection goals thoroughly. The regulatory body inside the company, the environmental protection department, carries out comprehensive tasks that include formulating internal environmental policies and guidelines and supervising the implementation process, compiling environmental risk responding plan, organizing training and emergency drills, regularly patrolling production facilities and pollutant discharge facilities, evaluating the environmental performance of each production unit and following China’s environmental regulations and standards closely.
Hongqiao strictly regulates the treatment and emission of “three wastes” – exhaust gas, wastewater, and waste, integrating environmental protection facilities into its production management system. It guarantees enduring and stable operation of the facilities by monitoring the compliance status and operating parameters of the outfalls with a 24-hour real-time surveillance system.
• Exhaust gas treatment.
The waste gas emitted by China Hongqiao mainly comes from power plant boilers and aluminum production. The company strictly abides by the Law of the People’s Republic of China on the Prevention and Control of Atmospheric Pollution and other relevant laws, purifying the exhaust gas in the plant to designated standards before emission. Automatic monitors installed at the exhaust outlet can upload real-time data to the government’s surveillance platform, helping the government’s environmental agencies to remotely supervise the company’s exhaust emission. Meanwhile, devoted to reduce emissions further and to improve the quality of the surrounding ecological environment, Hongqiao continuously invests in environmental protection funds for equipment upgrades. The company vows to excel in environmental protection in every single year. In 2018, it successfully transformed all generating units to achieve ultra-low emission and upgraded other equipment to both improve their performance and reduce emissions.
• Wastewater discharge
The wastewater discharged from China Hongqiao is mainly production wastewater and domestic sewage. The company complies with Chinese laws and regulations including the Law of the People’s Republic of China on Prevention and Control of Water Pollution, pretreats its wastewater to meet the Wastewater Quality Standards for Discharge to Municipal Sewers (GB/T 31962-2015) before discharging into the local municipal sewage treatment plant through the municipal pipe network. The environmental protection department conducts monthly sampling tests on the quality of water at sewage outlets, making sure they meet the standards. The outlets are also equipped with online monitoring systems that upload real-time data to government environmental protection agencies.
Hongqiao took comprehensive measures to improve the efficiency of water consumption and to prevent water pollution. All wastewater from alumina production is recycled, guaranteeing zero wastewater discharge. Cooling water used in the casting procession of electrolytic aluminum is reused. Discharged water from power plants’ cooling water towers first went for recycling. Spraying and cleaning water of the ex-factory vehicles are collected, recycled, and used in the coal yard spraying. Fluoride wastewater from the desulfurization process is processed with desiccant to reduce the fluoride content and recycled. Rainwater precipitation and purification tanks are established in aluminum plants to reduce aluminum oxide powder, fluoride salt, and other pollutants in the rainwater, to prevent polluted rainwater from being discharged, and to reuse some of the treated rainwater for production.
• Waste disposal.
The final solid waste from China Hongqiao can be divided into two categories: harmless waste and hazardous waste. The company implements relevant laws and regulations, including the Law of the People’s Republic of China on the Prevention and Control of Environment Pollution Caused by Solid Wastes, Pollution Control Standards for General Industrial Solid Waste Storage and Disposal Sites (GB 18599-2001) and Pollution Control Standards for Hazardous Waste Storage (GB 18597-2001) to ensure proper management of solid waste. The company is committed to reducing waste disposal through recycling. For example, Hongqiao adopts the twin-chamber melting furnace technology to melt the waste — waste with impurities, recovered materials from production, market collected waste and clean blocks — generated in the production process.
The company also reuses waste carbon slag (dregs) from the aluminum smelting process by flotation, which yields electrolyte powder and toner powder that could be put into future use. Electrolyte powder is both a raw material for electrolytic aluminum production and a product for sale. Carbon power, too, can be sold as raw material. Such a project both reduces pollution and generates considerable economic benefits for the company.
Hongqiao also highlights the treatment of another major solid waste – red mud, a strongly alkaline, harmful waste from the alumina production process. Hongqiao strictly follows relevant laws and regulations to prevent and monitor red mud pollution. After the dehydration and filtration, red mud is discharged into specially designed storage facilities with strict leakage prevention and other safety measures. Meanwhile, Hongqiao has set up control areas around alumina production and red mud storage facilities and built groundwater observation wells to monitor whether red mud is polluting the surrounding environment.