Preparation Of Environmental Ecological Construction Materials From Waste Foundry Sand

China is the largest producer of castings. More than30million tons of waste foundrysand is generated every year in China. The disposal of a large quantity of foundry sand,not only wastes resources, but also causes serious pollution to the environment. Thetreatment of waste foundry sand is more and more important in China.In this thesis, the foundry sand from Dongfeng Motor Co., Ltd. was used to prepareenvironmental ecological construction materials, the steam-cured bricks. XRD and SEMtechniques were used to analyze the mechanism of strength and durability contributor ofthe autoclaved bricks.Both performance and cost of bricks were considered as indicators to optimize thedosage of raw materials, molding parameters and curving conditions. Then the productswere tested comprehensively.Experiments show that:50wt%of waste foundry sand,15~20wt%of plant dry fly ash,15~20wt%stone scrapes,9~14wt%quicklime powder,0~1wt%cement,1~3wt%special additive in the8~12h aging, the moisture content of10~15%of molding underthe pressure of40MPa, standard brick products obtained can achieve the performanceMU15brick products in the GB11945-1999standard.A plant with50million foundry sand bricks was designed in this study. The benefits ofeconomic, environmental and social of the production line were analyzed. The totalinvention of the plant was13.979million Yuan, while the annual profit was about4.081million. Approximate64,800tons of waste foundry sands and25,920tons of fly ash willbe decreased annually.Waste foundry sand brick plant not only produces excellent building materials, but alsoconsumes waste foundry sands effectively. It also shows excellent economic,environmental, ecology and social benefit.