Development of environmentally friendly corrosion inhibitors for acidizing oil wells

Corrosion has an enormous economic and environmental impact on virtually all facets of infrastructure, from highways, bridges, and buildings to oil and gas, chemical processing, and water and wastewater systems. In addition to causing severe environmental damage and threats to public safety, corrosion disrupts operations and requires extensive repair and replacement of failed assets. The annual cost of corrosion worldwide was estimated to exceed US$ 2.5 trillion in 2016, which translates to 3 to 4% of the Gross Domestic Product (GDP) of industrialized countries. Saudi Arabia has an inherent corrosion problem. The King Fahd University of Petroleum and Minerals (KFUPM) and its associated Research Institute have been battling against this powerful enemy. The corrosion protection of steel structures has always been of chief concern for current research and development in Saudi Arabia as the country faces severe corrosion issues due to its huge economical and industrial development in the coastal zones. The yearly expenses due to corrosion issues on the gross national product (GNP) of the Kingdom is estimated to be about US$ 19.95 billion and it is anticipated that the total cost of corrosion in the Kingdom will rise in the upcoming years. Acidizing is a stimulation process carried out in oil and gas drilling for increasing the flow of oil by dissolving calcareous matter. For acidizing process, the most commonly used acids include HCl, HF, acetic, and formic acids with sulphuric, phosphoric, citric, and halo acids. To control the corrosion of tubular steels such as N80, L80 etc., inhibited acids are commonly used for this purpose. Most of the commercial inhibitor formulations include organic compounds as active components. However, the presently applied corrosion inhibitors are toxic, take long time and cumbersome synthesis methodology and are not cost effective. We herein, propose the use of naturally occurring biopolymers and environmentally friendly synthetic products to be evaluated as corrosion inhibitors on mild steel and tubular steels such as N80, L80 in 15% HCl solution. Effective formulations of corrosion will be developed by incorporating other additives such as surfactants, intensifiers, synergistic agents etc. Corrosion inhibition will be evaluated by weight loss method electrochemical measurements and surface analysis, and compare them with commercially available inhibitors. In addition, to validate the obtained experimental results, computational studies will be carried out.