Performance of High Temperature, Biodegradable Corrosion Inhibitors

In the UK, there are strict regulations that govern the use of production chemicals in offshore oil and gas fields. Production chemicals are required to have a good environmental profile and during the last decade many harmful products used offshore have been replaced with more environmentally friendly variants. In oil and gas production, corrosion inhibitors are commonly applied to mitigate the corrosion caused by acidic gases (CO₂ and H₂S) and environmentally friendly products are now widely used in offshore UK oilfields. However, the performance of these products is generally limited by the system temperature and it is accepted that above approximately 90°C (194°F) the efficacy of these products is greatly reduced. Therefore, considering that many new oilfields coming on stream in the UK are hotter than this, there is a necessity to develop corrosion inhibitors that not only perform at high temperature but are also environmentally friendly. This paper details the work performed to develop biodegradable corrosion inhibitors that are effective above 100°C (212°F). The performance of these products in preventing CO₂ corrosion in the laboratory environment is discussed and their effectiveness is compared to traditional chemistry.