METHOD OF OPERATION OF NATURAL GAS PRESSURE-REDUCING UNIT AND NATURAL GAS PRESSURE-REDUCING UNIT USED FOR REALIZATION OF THIS METHOD Russian patent published in 1997 - IPC

FIELD: gas transportation facilities; gas distributing stations and units for preparation of fuel gas for power plants. SUBSTANCE: in reducing the pressure of natural gas fed from high-pressure main, measures shall be taken to avoid salting of crystalline hydrates of natural gas in throttling members of pressure regulators. Method consists in cooling direct flow of natural gas, separated of crystalline hydrates salted-out in cooling followed by throttling of gas including formation of liquid phase and its separation. Innovation of method consists in deep drying of gas immediately before throttling through binding separated free moisture in crystalline hydrates and separating them from high-pressure gas flow. Separated crystalline hydrates are blown by part of return flow of gas delivered from intermediate section of heat exchange apparatus at temperature higher than 273 K; hydrate decomposition products are mixed with blowing flow and are directed for further heat exchange with direct flow of high-pressure gas. Natural gas pressure-reducing unit used for realization of above-mentioned method includes filters which are connected in turn to high-pressure gas flow after escape from heat exchange apparatus before throttling device. Filters are connected return flow passages by means of additional lines through shut-off fittings. EFFECT: enhanced reliability. 3 cl, 2 dwg