Jingbian-yanshuiguang Pipeline Gas Gathering Pipe In H < Sub > 2 < / Sub > S, Co < Sub > 2 < / Sub > Environment Corrosion Behavior Research

Corrosion becomes main obstacle on the sustainable development of oil field day by day. There have exist CO2, H2S, corrosiveness negative ion, scale formation cation, and other matters among produced liquid, under the condition of temperature and pressure, their existences and concentration changes will results different collector pipe corrosiveness on oil field, they also restrict with the development and production of hydrocarbon, so, it is very important to research corrosive behavior and mechanism of collector pipe corrosiveness, and relevant controllable technique. This paper selects20#、L360、X52steel as experimental material, and uses static corrosive soaking experiment, the experiment of which under the condition of high temperature, high pressure, and the reactor simulation corrosive media environment, electrochemistry and other ways. Meanwhile, the paper research three kind of steel’s corrosive influences, such as, different contents of H2S, CO2, and concentration of irons, temperature and other factors. The main conclusion including:1. It researched that different contents of H2S, CO2, and thermal changes will influenced collector pipe when using high temperature, high pressure, and the reactor simulation Jingbian gas field, at the same time, it used SEM、XRD analyze the changes of film morphology, component and composition of corrosive production. From the results, we can see that the change of H2S, CO2and temperature made big influence for material corrosive rate, and it exist completion and cooperation relationship among then, they have influence strength to corrosiveness from strong to weak as followed:temperature, H2S, CO2.2. It tested that different concentration of irons will impacted collector pipe corrosive rate, by using coupon soaking test and weight loss method test in the constant pressure liquor, and combined corrosive production from observing and analyzing SEM、EDS, the results shows that, Cl-, HCO3-, SO2-and other ions have influence for corrosive rate, the results as followed:Cl->HCO3->SO42-. But, in the total corrosive case, compared with temperature, H2S, CO2, these factors have less influence for collector pipe corrosiveness.3. The electrochemistry experimental results show that, different factors will influenced the corrosiveness of20#pipe steel as followed:temperature>H2S>Cl->HCO3->SO42-.The main factors are temperature, concentration of Cl-and H2S, and so on, the measured self-corrosion electrical density coincide with corrosive rate influencing rule which measured by test block weight loss experiment, it showed that electrochemistry test can reflect the corrosive case of carbon steel quickly and correctly.