METHOD FOR AUTOMATIC LOAD DISTRIBUTION BETWEEN LOW-TEMPERATURE GAS SEPARATION LINES AT GAS TREATMENT PLANTS OF OIL AND GAS CONDENSATE FIELDS OF NORTHERN RUSSIA

摘要

FIELD: oil, gas and coke-chemical industries.;SUBSTANCE: invention relates to the field of extraction and preparation of natural gas for long-distance transportation at complex gas treatment plants (CGTP) of oil and gas condensate fields (OGCF) of Northern Russia. Method includes monitoring by means of automatic process control system (APCS) of CGTP, flow rate of dried gas supplied to main gas pipeline (MGP), flow rate of unstable gas condensate (UGC) supplied to main condensate line (MCL), automatic maintenance of gas separation temperature in low-temperature separator of each technological line (TL) of low-temperature gas separation (LTGS) at a given gas flow rate therefrom by varying the degree of gas throttling on the union facing the separator. Task of the dispatcher of the gas producing company as per the volume of production of UGC is sent to the automated control system, which executes the task with the help of a proportional integral differentiating (PID) controller for maintaining the flow rate of UGC in the MCL, which is implemented on the basis of APCS. To the SP setting input of this PID-controller APCS sets the dispatcher setting signal. Simultaneously, APCS sends to its PV feedback input a signal of current flow rate of UGC in MCL. At the SP input, this proportional-integral-derivative controller (PID) controller of the APCS PID controller controls the dispatcher setting signal, and at the same time to its feedback input the PV signals the current flow rate of the UGC to the MCL. Simultaneously, to the PV feedback input of these PID controllers, the APCS sends a signal of actual flow of the dried gas to the CGTP. Also, at the input of CV of PID-controllers of each LTS TL, a signal of the coefficient of the proportionality factor C_{p_i}, (where i is the LTS TL number), which determines the degree of action of this PID-controller on the control valve (CV) of the gas flow rate through it LTS TL. Value of the coefficient of proportionality C_{p_i} is determined for each LTS TL by its proportionality coefficient calculation unit depending on the current temperature in the low-temperature separator of said lines by the readings recorded by the ACS with the help of a corresponding temperature sensor.;EFFECT: method provides a given degree of UGC extraction from natural gas at the CGTP in the initial and increasing stages of the OGCF operation with observance of the norms and restrictions on the process technological parameters, which are set by the process regulations of the installation, guaranteeing the specified quality of natural gas treatment for long-distance transport with simultaneous consideration of actual condition of the equipment of the plant.;4 cl, 2 dwg