Optimizing Natural Gas Liquid Production Using Near Infrared Spectroscopy
P. Harris, G. Bill. Canadian School of Hydrocarbon Measurement, Calgary AB (2018)
While the primary function of a gas plant is still the recovery and purification of methane for transport as natural gas, the importance of producing and purifying high value natural gas liquids (NGL‟s) and hydrocarbon condensates has increased dramatically in recent years. With the advent of hydraulic fracturing and shale gas production, many wells are now being drilled in liquids-rich formations.
Real time knowledge of the stream composition and its physical properties are necessary for effectively optimizing the operation of inlet separators, condensate stabilizers, and gas fractionation towers. Variations in feed composition, pressure, temperature, and flow rate can all affect operating parameters. Feedback control based on achieving target specifications allows a facility to maximize production rates. For many applications the goal is to maximize the amount of low molecular weight components in the product stream while ensuring that all custody transfer specifications are met. Achieving this optimization increases production volume while lowering fuel costs, greenhouse gas emissions, and potential VOC releases during vapor recovery. This optimization has been performed at several Encana Cutbank Ridge facilities using process Near Infrared (NIR) analyzers to provide the real-time compositional and vapor pressure results necessary for feedback control.