METHOD OF PRODUCING FUEL GAS FOR GAS PUMPING UNITS OF COMPRESSOR STATION AND LIQUEFIED HYDROGEN Russian patent published in 2024 - IPC C01B3/02 C01B3/24 B01J19/08 

FIELD: oil, gas and coke-chemical industry.

SUBSTANCE: invention relates to production of fuel gas for gas pumping units of a compressor station and liquefied hydrogen, performed in three steps; at the first stage natural gas from the main gas pipeline is throttled to 2.5–3 MPa, it is heated to 400–450 °C by the heat of exhaust gases of the gas turbine of the gas compressor unit and converted in corona electric discharge of high voltage of 20–40 kV to obtain synthesis gas. At the second stage, a smaller part of the air compressed in the compressor is supplied to the first stage of the combustion chamber — prechamber, synthesis gas and natural gas are supplied to its burners, the obtained "rich" mixture is burnt with an excess air factor of 0.6–0.7, flame temperature is increased to 1,350–1,400 °C and hydrogen fraction is increased to 7–10% due to thermal conversion of methane. At the third stage, compressed air is supplied to combustion products exiting the prechamber, this mixture is afterburned in the second stage of combustion chamber — afterburner, flame temperature is increased to 1,950–2,000 °C and hydrogen content is increased to 15–20% due to thermal conversion of methane; combustion products released from the afterburning chamber are diluted with compressed air to the required temperature before the gas turbine, expanded in the high-pressure turbine of the gas turbine to 3–3.5 kgf/cm², fed into a vortex centrifugal chamber, where they are separated into hydrogen and gases; released hydrogen is cooled by heat carrier to 40–50 °C, supplied to nitrogen-expander compressor unit, cooled to -252 °C, liquefied and directed into a liquid hydrogen storage tank; gases escaping from the vortex chamber are expanded in a medium-pressure turbine of a gas turbine, their heat is used to heat natural gas to 400–450 °C.

EFFECT: electric and high-temperature thermal conversion of methane contained in natural gas, with production of gaseous fuel for gas turbines and liquefied hydrogen for external consumers.

1 cl, 1 dwg