Reliable corrosion inhibition in the oil and gas industry RR 1023 Research Report
The objective of the work was to undertake a literature review on the subject of corrosion inhibition in the offshore oil and gas industry to understand the current issues. The application of chemical corrosion inhibitors can significantly reduce the rate of corrosion of carbon steel pipelines due to the presence of CO2 and/or H2S. An inhibited corrosion rate of 0.1 mm/year can typically be achieved, which is largely independent of the uninhibited corrosion rate. The report covers the main factors affecting the effectiveness of chemical corrosion inhibitors; they are not effective against corrosion due to the presence of oxygen or microbacterial corrosion. High flow rates, high temperature, solids (either dissolved or suspended) and pre-existing corrosion can all have a negative effect on corrosion inhibitor effectiveness. The role of Key Performance Indicators (KPIs), the main factors affecting the performance of inhibition injection systems, and the levels of inhibitor availability that can be assumed at the design stage and achieved in practice are also discussed. This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy. You may reuse this information (not including logos) free of charge in any format or medium, under the terms of the Open Government Licence. To view the licence visit Some images and illustrations may not be owned by the Crown so cannot be reproduced without permission of the copyright owner. Enquiries should be sent to Objectives To undertake a literature review on the subject of corrosion inhibition in the oil and gas industry to understand the current issues. Main Findings • The application of chemical corrosion inhibitors can significantly reduce the rate of corrosion of carbon steel pipelines due to the presence of CO 2 and/or H 2 S. An inhibited corrosion rate of 0.1 mm/year can typically be achieved, which is largely independent of the uninhibited corrosion rate; • Various factors can affect the effectiveness of chemical corrosion inhibitors; they are not effective against corrosion due to the presence of oxygen or microbacterial corrosion. High flow rates, high temperature, solids (either dissolved or suspended) and pre-existing corrosion can all have a negative effect on corrosion inhibitor effectiveness; • The main Key Performance Indicator (KPI) used for assessing effectiveness of corrosion inhibitors is based on the proportion of time that …
Interaction of Corrosion Inhibitors With Corroded Steel Surface
Effects of corrosion inhibitors on corrosion products of iron or steel in aqueous solutions are reviewed. Several organic and inorganic compounds seem to have sufficient inhibition effects on rusted surfaces, but details such as the mechanism or influence of solution properties are not known. Although the complexity of the chemistry of corrosion products makes it difficult to study the interaction between inhibitors and rusted steel surface, there is a need for a better understanding of the interaction to meet with success in a practical use of inhibitors.
Cross talk between redox signalling and metabolic activity of osteoblasts and fibroblasts in the presence of hydroxyapatite-based biomaterials influences bone regeneration
Regeneration of bone tissue defects that result from metabolic disorders, including periodontal diseases, can be supported by biomaterials based on hydroxyapatite. Despite of good biocompatibility of biomaterials they can cause oxidative stress and inflammatory processes as a result of mechanical interaction with surrounding tissues. Because osteoblasts are responsible for bone regeneration process in which gingival fibroblasts may also participate, the aim of the work was to investigate the influence of hydroxyapatite-based biomaterials (allogeneic and xenogeneic) and biomaterials combined with enamel matrix derivative (Emdogain) on osteoblast and fibroblast redox balance in the context of osteoblast proliferation and differentiation.
The results showed that examined substitutes were not cytotoxic in vitro, but affected redox balance of osteoblasts and fibroblasts (ROS level increase and GSH level decrease) which led to oxidative stress (MDA and protein carbonyl groups level increase) resulting in an increase of the Nrf2 and NFκB expression. The consequence of these changes was partial inhibition of proliferation and osteoblast differentiation. Emdogain alone and combined with biomaterials decreased ROS generation and increased GSH level in both osteoblasts and fibroblasts leading to reduction of transcription factors expression especially proinflammatory NFκB, which promoted osteoblast differentiation and mineralization process.