GENERATION MECHANISM AND CORROSION FOR HYDROGEN SULFIDE IN OIL WELL OF 3RD OIL PLANT IN QINGHAI OILFIELD

Based on formation mechanism of hydrogen sulfide for oil and gas field,the paper analyzes the reservoir characteristics and geological factors,H2S of NO.3 Oil Plant may be generated by sulfate thermo-chemical reaction(TSR).Corrosion studies are carried out for H2S concentration and situation of the oilfield,and the result shows that 20# and N80 of steel corrosion are moderate to mild.Corrosion result consists mainly of Fe,Cl,S and Mn elements and corrosion mechanism may be corrosion product film of H2S destroyed by chloride ions and the electrochemical corrosion of hydrogen sulfide.