METHOD FOR PREPARATION OF HYDROCARBON GAS TO TRANSPORTATION FROM NORTH OFFSHORE FIELDS Russian patent published in 2009 - IPC F25J3/00 F17D1/02 

FIELD: oil and gas production.

SUBSTANCE: invention is related to methods of low temperature preparation of multi-component hydrocarbon gases by means of extraction of condensed water vapours and liquid hydrocarbons at temperature of minus 50-60°C. In method for preparation of hydrocarbon gas to transportation from north offshore fields, including gas cooling by means of recuperation of prepared gas cold and application of processes of isoenthalpic or isentropic expansion, separation of condensate from cooled gas, degassing of condensate, ejection of gas released in process of degassing, by prepared gas with increase of their mixture pressure, separate discharge of prepared gas and condensate, initial gas is additionally cooled twice: first prior to recuperation by liquid, second after recuperation by mixture of gases before its pressure rise, after the second additional cooling condensate is separated from gas, afterwards gas is used as ejecting and, if required, in isentropic expansion process, and excess heat from liquid is sent to environment.

EFFECT: higher efficiency of hydrocarbon gas preparation, by means of increase of discharge of condensed hydrocarbon components die to reduction of prepared gas cooling temperature of minus 50-60°C and hydrocarbon condensate, by means of its degassing at pressures of at least 4,0 MPa.

6 cl, 9 dwg