Method of controlling a gas vent system for horizontal wells

A method of controlling a gas vent system that includes a gas vent choke valve to vent gas from a wellbore that includes a substantially horizontal portion, the wellbore configured to channel a mixture of fluids, said method comprising:

• determining an initial operating mode of the gas vent system by determining an initial target downhole pressure (PDH) set point, setting a gas venting rate to fluctuate above and below the initial target downhole pressure (PDH) set point and measuring and comparing a dynamic response of the downhole pressure (PDH) to the gas venting rate;
• generating one or more control signals established for the determined initial operation mode;
• and
• transmitting the one or more control signals to a gas vent choke valve that commands a closing or opening of the gas vent choke valve.

A controller for use in venting gas from a wellbore, the wellbore including a substantially horizontal portion, the wellbore configured to channel a mixture of fluids, said controller configured to:

• determine an initial operating mode of a gas vent system by determining a downhole pressure (PDH) and a gas venting rate of the gas vent system;
• generate one or more control signals established for the determined initial operation mode;
• detect whether a periodic increase in the gas venting rate results in one of an increase or a decrease of the downhole pressure (PDH) by calculating and comparing one of:
• calculating and comparing a phase difference in oscillations in downhole pressure (PDH) with oscillations in the initial target venting rate set point calculating and comparing a gradient with a target gradient;
• or
• calculating and comparing a measured current with a target electric submersible pump (ESP) current, and
• employ one or more control laws for one of:
• a gradient mode of operation as a result of one of a calculated phase difference between oscillations in downhole pressure (PDH) and oscillations in the target gas venting rate set point less than a target phase difference, a calculated gradient less than the target gradient, or a calculated ESP current less than the target ESP current, or
• a level mode of operation as a result of one of a calculated phase difference between oscillations in downhole pressure (PDH) and oscillations in the target gas venting rate set point is more than a target phase difference, a calculated gradient greater than the target gradient, or a calculated ESP current greater than the target ESP current;
• and
• transmit the one or more control signals to a gas vent choke valve that commands a closing or opening of the gas vent choke valve.