Project partner

China University of Petroleum (UPC) is amongst top 1% of Chinese universities (there are more than 5,000) and one of the top 3 universities of petroleum engineering, energy and chemical engineering in China. UPC cooperated with most of the Chinese oil and gas refining and exploration state companies and possesses crucial national laboratories for instrumental analysis and analytical chemistry, applied chemistry, and materials chemistry. School of Petroleum Engineering and the Key Laboratory of Oilfield Chemistry in the Shandong province are one of the most important faculties at the UPC.

Head of the partner research group Yefei Wang obtained his Ph.D. in oil & gas field development engineering at the UPC in 1998 and continued his postdoctoral studies at the company  Sinopec Shengli Oilfield Co Ltd in the city of Dongying, working at the second largest oilfield in China. He was dean of the Department of Oilfield Chemistry from 2009 to 2013 and vice president of the School of Petroleum Engineering from 2013 to 2017. His fields of expertise are oilfield fine chemical products, corrosion and protection, corrosion inhibitors, oilfield production and operation chemistry, chemical flooding and chemical treatment of production and injection wells. Yefei Wang is currently a professor and researcher at the Department of Oilfield Chemistry at the School of Petroleum Engineering, UPC. He is also the vice director of Shandong Key laboratory of Oilfield Chemistry.

Project Description

Aim of the proposed project is the development of corrosion-mitigating thin surface coatings (thin layers) on metallic materials using various surface treatment procedures. More specifically, development of environmentally friendly corrosion inhibitor formulations (CIFs) that protect steel materials against acid corrosion in oil and gas wells during the acidizing procedure and study of their mechanisms.

Despite tremendous efforts to develop efficient ways of using alternative energy sources, human demand for fossil fuels is still growing. Oil and natural gas account for 60% of all global energy demand. It is thus not expected that the conventional method of extracting fossil fuels will disappear within the next few decades. Since accidental discharges of the acidizing fluids into the environment might occur during the drilling process, concerns regarding environmental pollution and personnel safety continue to be a pressing issue.

Accidental discharges of drilling fluids occur in drilling applications even though a great deal of effort is devoted to preventative measures. Such accidents are particularly problematic when drilling is being performed on the sea floor and near groundwater sources. In the event of accidental discharges, application of a more environmentally acceptable acidizing solution would contribute to the preservation of marine life and drinking water for future generations. Moreover, hazard for the drilling crews would be drastically reduced.

The technology developed in this project is also applicable for acid decantation, pickling, industrial cleaning, acid descaling, and other processes that require the use of corrosion inhibitors for steel materials. It must be emphasized that the previously mentioned technologies are part of several different industrial processes, which is why such technological solutions would benefit many different companies. For example, steel pipelines corrode during the decantation of acids at elevated temperatures. Therefore, an appropriate (especially non-toxic) corrosion inhibitor formulation is required to prevent equipment failure.

Project Stages

  1. Selection or preparation of the corrosion inhibitor formulations (CIFs) for corrosion testing.
  2. Sample preparation, sample cleaning, selection of experimental parameters for immersion/autoclave and electrochemical tests.
  3. Screening of CIF performance using autoclaves with an inner liner made of Teflon. Investigation of corrosion inhibition mechanism on a molecular level.
  4. Surface roughness measurements, evaluation of pitting formation and the rate of pitting corrosion, analysis of surface morphology as well as the chemical composition of the adsorbed corrosion-inhibiting film.
  5. Characterization of CIF performance under sweet and sour conditions using gas/pressure controlled autoclaves.
  6. Concentration optimization for the CIFs found to be effective.
  7. Characterization of inhibition performance of CIFs, their film formation processes, and mechanism types using electrochemical measurements.
  8. Characterization of corrosion products and evaluation of thickness of protective surface layers, according to the results obtained in stage 3.
  9. Study of corrosion-induced cracking.
  10. Field tests.


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