Liquid level-pressure coordinated control method used for gas-liquid separator

Abstract

The invention relates to a liquid level-pressure coordinated control method used for a gas-liquid separator, used to set a liquid level-pressure coordinated control device. The method comprises: presetting each target value and opening initial values; determining whether gas-phase pressure is larger than a preset gas-phase pressure target value, calculating a valve opening value of a first pneumatic control valve and feeding back to a valve to operate; determining the relations between the difference value of the maximum value and the minimum value of pressure measuring values and pressure fluctuation errors; determining whether liquid level measuring values are larger than a preset liquid level height target value, calculating the valve opening value of a second pneumatic control valve and feeding back to a valve to operate; determining relations between the difference value of the maximum value and the minimum value of liquid level measuring values and liquid level fluctuation errors; performing simple control on gas-phase pressure and liquid level height in the gas-liquid separator; determining received liquid level height; and a liquid level-pressure operation control module determining whether the received gas-phase pressure exceeds an error range, and determining whether the received liquid level height exceeds an error range.

Description

technical field [0001] The invention relates to a method for stabilizing the liquid level control of a gas-liquid separator, in particular to a pressure-liquid level linkage control method for gas-liquid separators in land and offshore oil fields in the technical field of petroleum engineering multiphase fluid control. Background technique [0002] During the exploitation of offshore oil and gas fields, in order to reduce production costs and improve transportation efficiency, the produced oil-gas-water multiphase mixture is often transported to offshore platforms through subsea mixed pipelines and standpipes, in order to separate gas and liquid on the platform , and at the same time avoid affecting the normal production of offshore oil and gas fields when slug flow or severe slug flow occurs in the gathering pipeline-standpipe, a gas-liquid separator must be installed at the outlet of the riser pipe. In the process of onshore oil and gas transportation, gas-liquid separator...

AI Technical Summary

Problems solved by technology

Although the variable pressure control can stabilize the liquid level in the separator, it cannot provide stable pressure, which will have adverse effects on the slug control mechanism in front of the separator and the processing equipment after the separator. Submersible pumps, self-flowing wells and power generation systems have adverse effects. Therefore, offshore oil production platforms mostly use constant pressure control schemes

Traditional constant pressure control uses self-operated regulating valves, liquid level sensors, controllers, oil outlet valves and other devices to individually adjust pressure and liquid level to keep them in a relatively stable range, but for sudden changes in liquid volume, this The control method is not conducive to the stability of the liquid level

Images