Study On Removing Acid Gas From Associated Gas In Oil Field

The content of CO₂ in associated natural gas of Daqing Oil field has an apparent upward trend in recentyears, which has an unfavorable effect on the Natural Gas Cryogenic Plants and the downstream EthyleneFactory. So it will have a practical significance to remove acid gases from associated gas with effectivemeasures. At present, there is neither mature technology to fulfill this in domestic market nor too muchapplied cases in similar situation in abroad industry, so it is necessary to research.Industrial methods to remove CO₂ include PSA, Rectiso, Membrane and MDEA. The most commonlyused solvent in chemical solvents absorption process is mixed amines. The process to remove acid gaseswith mixed amines has many advantages including low energy consumption, high processing capacity andlight corrosion, which is favorable for removing CO₂ from gases. This paper takes associated natural gas ofDaqing Oilfield as investigated subject and Study suitable technology to remove acid gases with mixedamines. Suitable compounding of mixed amines, the relation of solubility of H₂S, CO₂ and C₁-C₈ incompounded amines and temperature, pressure and composition of gases. Based on research findings, acorrelation formula for calculating velocity of mixed amine's absorption velocity of CO2 is established. Ahemi-theoretic and hemi-empirical formula for calculating CO₂'s solubility factor in this mixed aminesunder different temperature and concentration and a two stage reaction velocity correlation formula of thesemixed amine's absorption of CO₂ are also determined.Based on research results, a rather integrated processdesign is completed for building plant to remove CO₂ from associated natural gas, which includes materialbalance, process flow, main equipment, consumption of absorbent and public facilities, investment estimateare involved..