Balancing Relief Gas and Assist Gas Flows for Efficient Flare Gas Combustion in Onshore Gas Facility
Abstract
This study investigates the interplay between relief gas and assists gas flows in onshore gas facilities, focusing on their impact on flare gas combustion efficiency. The primary objectives of this study are to analyze how relief gas flow rate, CO₂ and H₂S compositions, and the mixed-gas flow ratio influence the assist gas requirement, the mixed-gas calorific value, the flare gas composition, and the overall gas mix ratio. Additionally, the study evaluates flare gas monitoring to ensure compliance with environmental regulations. The comprehensive analysis aims to enhance the understanding of these variables’ interactions and their effects on gas systems, contributing to improved industrial sustainability and efficiency. Increasing relief gas flow reduces assist gas demand, raises the mixed-gas calorific value and SO₂ concentration, and lowers CO₂ levels. Higher CO₂ content in the relief gas decreases the calorific value and increases CO₂ concentration without significantly affecting relief gas flow. Increasing H₂S content raises the calorific value and SO₂ concentration while reducing CO₂. A higher gas-mix flow ratio also lowers CO₂ and increases SO₂, with the minimum LHV of 300 BTU/SCF occurring at a ratio of 10.69. Monitoring results confirm that all flare emissions remain within government regulatory limits.
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