China Energy Construction has launched China’s first project in Datong Town, Shanxi Province, on processing coal gangue – a waste product of coal mining. This ten-million-ton project is of great significance for establishing a complete carbon recycling system, a broader use of industrial waste in construction and promotion of the idea of a “zero-waste city”.
Coal gangue is an inevitable by-product of coal mining. It usually accounts for more than 10% of the total production. But if this waste is not recycled, it stockpiles and occupies large areas, causes such serious environmental issues as spontaneous combustion, water, soil and air contamination. China has already accumulated more than 7 billion tons of coal gangue, with another 500 million tons generated each year. Utilization rate is less than 60%, which makes it a big environmental burden and hinders the development of cities dependent on the coal industry.
To address this problem, China Energy Construction has launched the country’s first demonstration recycling project of this scale in Datong. It is based on the “1267” technical concept: one crushing and screening plant, two photovoltaic sorters, six key operations and seven high value-added products at the output. The resulting materials have application in construction, chemistry and medicine, forming a closed chain: from industrial waste to environmentally friendly products.
The project is based on six cutting-edge innovations. For example, a belt firing method borrowed from steel industry is used for the production of expanded clay, which raises productivity. A unique X-ray and electromagnetic wave cleaning system used to effectively remove iron from the raw material and improve the final product quality. Micron-level calcination technology helps to achieve almost complete (99.5%) decarbonization. This solution opens up new opportunities for prefabricated housing industry.
This is the first project of this kind in China, focused on production of green building materials and comprehensive utilization of large volumes of coal gangue. The project demonstrates a new recycling model that can be replicated nationwide now.
