Sweet gas corrosion

Peculiarities of metal equipment protection during the production of sweet hydrocarbon gas

example of Sweet gas corrosion
A huge number of explored gas and gas condensate fields exist in many countries all over the world. At present the proved reserves of gas amount to more than 170 billion tons. One of the reasons preventing these depositsfrom being fully operational lies in the fact that these reserves are located in large fields with CO2 in adverse climatic conditions. So, for example, in Canada the fields with gas and oil contain large quantities of carbon dioxide gas (CO2) that amount to 10–15%, while at individual fields these quantities may reach 90%. The same problem exists at deposits in Asia, for example, in Indonesia the content of CO2 in natural gas may reach 70%.

Corrosion inhibitors DEFENDER

Multifunctional Corrosion Inhibitors for oil and gas industry

Sweet gas corrosion protection
A considerable amount of CO2 in natural gas or gas condensate becomes a problem due to high corrosive activity of this gas in relation to metals in the medium with even minimum amount of water. The natural gas that actually does not contain hydrogen sulfide, but contains carbon dioxide gas is usually classified as sweet. The corrosion occurring during the production and transportation of sweet gas is determined by dissolution of CO2 in water that results in the formation of carbon dioxide and H+ ions. In this case the corrosion damages mostly will be of pit and honey-comb nature; it is just this feature that makes corrosion so dangerous. Initially, the development of these deposits will require the application of expensive corrosion-resisting alloys due to the possibility of high corrosion of CO2. The bottom line is the fact that the project development will be economically-prohibitive. An alternative approach could have implied the use of special carbon steels. However, it also cannot fully solve the problem. The simplest for application approach aimed at controlling the pipe corrosion during the production of gas and gas condensate is the use of corrosion inhibitors that will be most effective in handling the corrosion in the sweet gas medium.

Washing and anticorrosive fluids WINCOR

Washing and anticorrosive fluids WINCOR

removal of asphalt-resin-paraffin,  mineral, mechanical depositions, corrosion products, protection of metal equipment from carbon dioxide and hydrogen sulfide corrosion at enterprises of the oil-and-gas production and processing branches of industry.

Sweet gas corrosion protection

Sweet gas corrosion protection

HIMIPEX Company has developed corrosion inhibitors of DEFENDER series that were successfully tested at a gas condensate field of the oil-and-gas producing enterprise in Asia.

Dosage: 20–40 g of inhibitor per 1000 m3 of gas (while using the method of “shock” dosages). Problematics of the facility:high corrosion rates of pumping and compression pipes (production tubing) stimulated by high content (above 5%) of carbon dioxide (CO2) in the system.

Customer feedback on the application results:

High efficiency of the inhibitor (deceleration of corrosion rate amounted to 10–12 times). After feeding of the inhibitor “shock” dosage and stabilization of protective film of the corrosion inhibitor on the surface of pumping and compression pipes (production tubing), the inhibitor dosage was reduced to 10–20 g/1000 m3 of gas. The slowdown of corrosion damages of equipment, including damages caused by local types of corrosion in stratal water amounted to more than 90%.

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