Utilizing Hydraulic Barriers to Reduce Leakage of Hot Water and Enhance Sulphur Production at Mishraq MineNorthern Iraq

Abstract

Sulphur is produced at Mishraq mine by hydrodynamic method (modified Frasch method) of injecting super – heated water 165؛C through a special well in to the sulphur horizons to melt the sulphur underground. A seepage of super–heated water at 132؛ C to the Tigris River has been noticed, which cause drop in deposit pressure as well as polluting the river water. A drop of sulphur productivity has also been noticed in some regions of the mine despite of their content of high sulphur percentage, and injection of huge quantities of hot water.Hydraulic barriers were located according to the transmissibility and temperature distribution maps. The barriers consist of wells especially designed for injection of cold water down to the sulphur horizons. The barriers were shown to be very effective in increasing the ground water pressure and decreasing the hot water seepage to the river, and dropped the general hot water factor (m3 water/1ton sulphur), from 20.0 to 12.0; besides, the productivity of sulphur increased from 1.5 ton/hr to 5 ton/hr.