Excessive removal of gypsum is expected to speed up digestion

The use of gypsum in China is still in its infancy, and it can only be used as a coagulant to add cement. However, the reporter learned last week from the Shanghai Municipal Association of Resources Comprehensive Utilization that a new technology with independent intellectual property rights and in line with China’s national conditions is The use of off-gypsum as raw material for the production of inorganic thermal insulation mortar for external walls has been successfully developed and realized industrial production, and it has found an ideal way for China to digest large amounts of excess desludging gypsum.

This reporter learned that this new technology was jointly developed by the Shanghai City Construction Materials Technology Research Center and the Shanghai Academy of Building Sciences and the Chinese Academy of Sciences. Currently, the 10,000 tons of inorganic insulation mortar production line has been partially put into production. The product has been successfully used in construction projects. Exterior wall material. This technology can not only digest off the waste residue, but also finds insulation and safety functions for the building energy-saving industry.

Currently, the wet limestone-gypsum technology is the most widely used in many flue gas desulfurization technologies, and the corresponding output of gypsum is rapidly increasing. Chen Keke, head of the technical center of Shanghai Urban Construction Materials Co., told the reporter: “We combined the national conditions of China and adopted a technological route that is different from that of foreign countries. We used gypsum for inorganic insulation materials and achieved gratifying results.” The thermal insulation system has good thermal insulation properties. The thermal conductivity of gypsum lightweight mortar is only one-fifth that of cement mortar, and the thermal conductivity of gypsum-based inorganic thermal insulation mortar is one-tenth that of cement mortar, which can significantly improve the building energy-saving effect. In addition, the inorganic thermal insulation mortar has excellent fireproof performance and its flame retardant performance reaches Class A. Under the background of vigorous development of energy-saving buildings in the national "Twelfth Five-Year Plan" period, the promotion of the removal of gypsum inorganic insulation system has opened up a vast market for the comprehensive utilization of waste residue. With a new 15 million square meters of affordable housing in Shanghai a year, it can digest nearly 350,000 tons of off-site construction gypsum, equivalent to 450,000 tons of waste residue.

According to the person in charge of the Shanghai Municipal Economic and Information Commission, the successful development of the inorganic thermal insulation mortar system is conducive to the formation of a large-scale industrial chain of “power plant raw materials - de-*gypsum-construction gypsum powder-insulation mortar” to alleviate the current energy conservation and fire protection of buildings. Contradictions have opened up a viable low-cost route for the emerging domestic building energy-saving industry, and at the same time, they can absorb the rapid growth of de- gypsum.

It is understood that in the developed countries, off * gypsum is mainly used for the production of building gypsum, plastering plaster, cement accessories and new blocks, etc., also used for agricultural fertilizer, saline-alkali land reform, roadbed backfill materials. In China, the use of gypsum removal is still in its infancy. Most of them are used as coagulants in cement, and the way out of gypsum has always been a difficult problem.