China produces more than 30 million tons of foundry used sand every year, and some large foundry enterprises discharge more than 100000 tons of foundry waste sand every year. The abandonment of foundry waste sand causes a large waste of silica sand resources, brings huge economic burden to enterprises, and also puts great pressure on China’s resources and environment. Therefore, the treatment, recycling and reuse of foundry waste sand has become an urgent problem to be solved in China, which is of great significance for the green and sustainable development of China’s foundry industry.
At present, the research on low-cost and non emission regeneration and reuse technology of used foundry sand mainly includes the development of new regeneration technology of used foundry sand and high-efficiency regeneration equipment. The new technology of regeneration of used foundry sand is mainly aimed at the current situation that most of the existing dry, wet and thermal regeneration technologies are only aimed at the single used foundry sand, and develops composite regeneration methods based on mixed waste sand, such as “dry wet”, “dry thermal”, “dry wet thermal” and other composite regeneration technologies, using composite regeneration technology with low cost High quality and no secondary discharge recycled casting waste sand.
In the regeneration and reuse technology of used foundry sand, the reclaimed sand after wet regeneration and thermal regeneration is of high quality and can be used instead of new sand. Therefore, the development of efficient regeneration equipment for the regeneration of used foundry sand is mainly aimed at wet regeneration equipment, thermal regeneration equipment and “wet thermal” composite regeneration equipment based on the principle of In the regeneration and reuse technology of used foundry sand, the reclaimed sand after wet regeneration and thermal regeneration is of high quality and can be used instead of new sand. Therefore, the development of efficient regeneration equipment for the regeneration of used foundry sand is mainly aimed at wet regeneration equipment, thermal regeneration equipment and “wet thermal” composite regeneration equipment based on the principle of composite regeneration of used foundry sand. For example, develop high-efficiency wet regeneration equipment (including high-efficiency wet regeneration machine (including continuous and interval regeneration machine)), wet sand dehydration equipment, water sand separation, sewage treatment and other key equipment; develop high-temperature thermal regeneration furnace (110 ~ 150 ℃ low-temperature drying furnace, 300 ~ 350 ℃ medium temperature heating furnace, 700 ~ 800 ℃ high-temperature baking furnace), etc., high-temperature furnace waste heat utilization technology and methods, build a complete set of technology and equipment system for high-efficiency and low-cost thermal regeneration and reuse of cast old sand, and build a production line of high-efficiency mixed cast waste sand composite regeneration equipment and various wet and thermal regeneration methods The connection mode of production equipment can realize the low-cost regeneration and reuse of a large number of mixed casting waste sand.