Abstract
Use of near-infrared (NIR) spectroscopy for Reid Vapor Pressure (RVP) measurement has enabled condensate stabilizers at natural gas separation sites to optimize their operation, resulting in significantly lower energy usage, less gas production, more liquid conserved, more on-spec product, and higher profitability. The combination of energy usage optimization and an improved liquid/gas ratio provides a double benefit in both Environmental, Social, and Governance (ESG) criteria and return on investment (ROI). Optimization is achieved by utilizing the 15-second measurement interval of the JP3 Verax NIR on-line analyzer for process control, as compared to manual control. In condensate stabilizers, RVP is reduced by removing light components (C4-: butanes and lighter hydrocarbons) by heating; these are sent to a compressor for vapor recovery. In many instances, the light hydrocarbon gas is flared off when it is uneconomical to transport it for sale. The remaining condensate goes to a reboiler and a cooler before being sent to pipeline. The reboiler heats the liquid fraction before recirculating it to the column; the cooler uses pumped water in a heat exchanger to reduce the stabilized condensate temperature and vapor pressure for storage and transport.
These are energy-intensive processes – the compressors use electricity, the reboiler burns fuel gas, the coolers use electricity and large volumes of water, and waste gas flaring impacts carbon credits and allowances. Optimizing these processes via real-time process control informed by RVP measurement can provide substantial benefits in each energy-consuming step.
