开封市位于黄河岸边，引黄灌溉所淤粘土廉价易得，因而粘土砖盛行，每块仅８～９分钱，给发展以废渣为材料的新型墙材带来很大冲击。近年来，由于政府支持及出台相关优惠政策，废渣空心砌块得到发展，已建起废渣砌块厂７家，拥有中小型生产线８条，一条引进国外大型生产线的计 Kaifeng City is located on the bank of the Yellow River, and the dredged clay from Yellow River Irrigation is cheap and easy to obtain. As a result, clay bricks are prevalent, and each block is only 8 to 9 cents, which has brought great impact on the development of new wall materials made of waste residue. In recent years, thanks to government support and the introduction of related preferential policies, waste residue hollow blocks have been developed. There are 7 waste slag block plants, 8 small and medium-sized production lines, and one imported large-scale production line.