A LIQUID NITROGEN SYSTEM AND METHOD TO GOVERN FIRE DISTRICT IN COAL FIELD LOSSLESSLY

摘要

Provided are a liquid nitrogen system and method for nondestructively controlling spontaneous combustion of coal. An air filter (1), an air compressor (2), an air cooler (3), an oil-water separator (4), an air drying purifier (5), an air separation tower (6), a liquid nitrogen tank (7), and a booster pump (8) are connected by a pipeline in sequence. Liquid nitrogen tanker (9) is connected with input ends of boreholes (10) and an output end of the booster pump (8), the boreholes (10) and a geothermal well (12) are located in the at the fire area in the coalfield, a geothermal power generation apparatus (11) generates electricity to supply power to all apparatuses above via high-temperature steam provided by the geothermal well (12). The liquid nitrogen system and method take advantage of waste heat produced by the fire area in the coalfield to generate geothermal power, reducing energy wastage. The use of the liquid-nitrogen fire prevention and extinguishing techniques to control coal fire with the liquid nitrogen sourced from nitrogen in air and afterwards returning to the air again, thereby recycling the extracted liquid nitrogen, does not damage the environment and enables resource recycling and reusing.