METHOD FOR PROTECTING/PURIFYING WATER BY RECHARGING IRON-CONTAINING SEWAGE INTO STRATUM DESTROYED BY COAL MINING

摘要

Disclosed is a method for protecting/purifying water by recharging iron-containing sewage into a stratum destroyed by coal mining. According to the method, iron-containing sewage recharging holes and oxygen-containing water/weak alkali water recharging holes are drilled in the ground surface corresponding to the boundary and middle of a mining area, respectively; mining-induced fractures are effectively blocked by means of Fe(OH)₃ flocculation sediments generated by the oxidation reaction between iron components in the iron-containing sewage and the oxygen-containing water/weak alkali water. The generated Fe(OH)₃ flocculates can gradually precipitate within a certain range near the recharging holes to form an iron active filter membrane, so that a catalyst effect is achieved on the oxidation reaction of iron or ferrous ions, thereby effectively ensuring an iron removal effect. Iron components in a water resource gushing from a low-lying position in a downhole mined-out area are tested; if the iron components still exceed the standard, the downhole gushing water is delivered to a relatively high-lying position by means of pipelines and recharged into the water-containing layer of the stratum again by means of downhole inclined construction holes to continue oxidation reaction and iron removal; and if the iron components of the downhole gushing water do not exceed the standard, the water is directly delivered to other mining areas or to the ground for reuse.