The development of manganese mines has prospered with the rapid development of China’s economy. Manganese tailings have not been reasonably and effectively studied due to capital constraints and backward technology, directly leading to ecological damage, environmental pollution, fast urban development, and incomplete city construction. In China, these phenomena have resulted in long-term waterlogging in the southern cities and water shortages in the northern cities. Permeable bricks, which are prepared through the sintering of manganese tailings, serve as materials for the construction of sponge cities, ease environmental pressure to a certain extent, and contribute to ecological restoration. In this paper, manganese tailings, kaolin, and calcium oxide are used as main raw material, binder, and sintering aid, respectively. The materials are mixed at a certain ratio and subjected to ball milling, sieving, batching, and foaming. The slurry is molded and sintered at a high temperature to obtain permeable bricks that perform well in terms of porosity, compressive strength, and water permeability. Based on the performance of permeable bricks prepared using manganese tailings, the optimal firing system for preparing the porous materials of manganese tailings is as follows: sintering temperature, 1,030 ^oC; heating rate, 6 ^oC/min; and holding time, 1 h. The permeable brick prepared using manganese tailings has porosity, shrinkage, compressive strength, and water permeability of about 71%, 8.7%, 2.68 MPa, and 2.2 × 10⁻² cm/s, respectively.

Keywords: manganese tailings, permeable brick, sintering process, permeability, compressive strength