System and Method for Intelligent Flow Control System for Production Cementing Returns

A system of controlling and monitoring a cementing process injecting a cement slurry down a well that causes a return of a drilling fluid in a primary return conduit, comprising:

• a first flowmeter disposed in the primary return conduit configured to generate a first flow rate of the returned drilling fluid;
• a second flowmeter disposed in the primary return conduit configured to generate a second flow rate of the returned drilling fluid;
• a first control valve downstream from the first and second flowmeters configured to regulate conducting the returned drilling fluid to a reservoir;
• a choke valve disposed downstream from the first and second flowmeters configured to regulate diverting the returned drilling fluid in the primary return conduit;
• a mud-gas separator disposed in the primary return conduit downstream from the choke valve configured to receive the diverted drilling fluid and separate the diverted drilling fluid into a mud component for return to the reservoir and a gas component for controlled burn off;
• and
• a microprocessor configured to receive the first and second flow rates, determine a presence of gas in the returned drilling fluid in response to a comparison of the first and second flow rates, and regulate the actuation of the first control valve and choke valve to conduct the drilling fluid to the fluid reservoir in the absence of gas in the drilling fluid, and conduct the drilling fluid to the mud-gas separator in the presence of gas in the drilling fluid.

A method of controlling and monitoring a cementing process injecting a cement slurry down a well that causes a return of a drilling fluid at a wellhead, comprising:

• measuring at least two flow rates of the returned drilling fluid;
• determining one of absence and presence of gas in the returned drilling fluid by analyzing the at least two flow rates;
• controllably conducting the returned drilling fluid to a reservoir in response to a determination of an absence of gas in the returned drilling fluid;
• and
• controllably diverting the returned drilling fluid to a mud-gas separator configured to separate the returned drilling fluid into a mud component for return to the reservoir and a gas component for controlled burn off in response to a determination of a presence of gas in the returned drilling fluid.