NATURAL GAS DISTRIBUTION METHOD WITH SIMULTANEOUS PRODUCTION OF LIQUEFIED GAS AT TRANSPORTATION TO CONSUMER FROM HIGH-PRESSURE MAIN PIPELINE TO LOW-PRESSURE PIPELINE Russian patent published in 2014 - IPC F17D1/07 F25B11/02 F25J1/00 

FIELD: oil and gas industry.

SUBSTANCE: method is intended for the distribution of low-pressure natural gas to consumers with the production of liquefied gas. The method lies in the extraction of a gas flow from the high-pressure main pipeline, its expansion in a multistage turbine with the production of mechanical energy, heat exchange in a heat exchanger and distribution of the received low-pressure gas to the consumer, at that the gas from the high-pressure main pipeline is directed to an input of a heat carrier loop in a heat exchanger and cooled, while at the loop output it is directed to a multistage turbine where the cooled gas flow is expanded up to a pressure less than the preset distribution pressure in the low-pressure pipeline, at which the fed flow of the liquefied natural gas changes its parameters and aggregative state, transiting from a single-phase state at the multistage turbine input to a double-phase state at the turbine output; at that a liquid phase is separated from the latter and sent for distribution to the liquefied gas pipeline while the remaining part upon separation is sent to the input of the cold carrier loop in the heat exchanger to heat it up for heat exchange with the flow of the liquefied natural gas fed from the high-pressure main pipeline, and further this part is compressed in a bootstrap system up to a pressure equal to the pressure in the low-pressure pipeline, heating it up simultaneously up to positive temperature values, and then it is sent for distribution to the low-pressure pipeline; at that for the compression of this gas part in the compressor mechanical expansion energy is used, which is received at the multistage turbine; moreover, the separation of the liquefied natural gas part takes place after each stage of the turbine.

EFFECT: development of a highly-efficient method of natural gas distribution with simultaneous maximum output of liquefied gas due to mechanical energy produced in result of expansion when pressure drop occurs in the high-pressure main pipeline and low-pressure pipeline.

3 cl, 1 dwg