From a Research Project to a Commercialized Patent: H2S scavenger..A new Chemical Developed by KFUPM Researchers

KFUPM researchers have invented a chemical, called H2S scavenger, to reduce the effect of Hydrogen sulfide gases normally produced during oil and gas operations. The newly developed chemical formula is easy to manufacture and has wide-ranging applications in the exploration and production sectors of the oil industry. A Saudi company providing innovative services and solutions to regional oil and gas operators, has concluded an agreement with the University for commercializing this patent. The successful use of this technology is expected to reduce operating costs and the required infrastructure by about US $ 200 million.

The developed scavenger can be used with any type of water-based drilling fluid and it will help to protect the drilling equipment, drilling crew and will reduce the total cost of the drilling operation by reducing the non-productive time.

Hydrogen sulfide (H2S) is soluble in water, alcohol, and oil. In addition, it is malodorous, colorless, highly corrosive and toxic gas. H2S can be originated from geological sources or bacterial sources. H2S can also be produced by microbiological processes, for example the reduction of sulfates by anaerobic bacteria such as sulfate reducing bacteria (SRBs). The existence of hydrogen sulfide even at low concentration yielded in localized corrosion and cause stress cracking.

In drilling operations, H2S can be generated from drilling H2S bearing formation, hot decomposition of mud additives, sulfur-bearing oil, and metabolism of (SRB). In general, the main source is the H2S -bearing formations. It is better to scavenge H2S once the formation is penetrated to protect the drilling equipment, save the drilling fluid integrity and protect the drilling crew.

After evaluating the existing solutions for H2S scavenging during the drilling operation, we found that there is big chance to develop a sheep and environmentally friendly solution with high capacity for H2S adsorption while drilling horizontal and multilaterals wells.

Advantages

The develop invention for H2S scavenging has many advantages such as very sheep and has a hug capacity for H2S absorption as compared with the existing products (Triazine, SourScave and others), long working time than the available products, it is environmentally friendly and will not cause formation damage when using it, the more resistance to solidification of the developed drilling fluid when reacted with the developed scavenger, compared with the conventional scavenging drilling fluids additives. The sorption capacity of the developed fluid is 5143 mg H2S/ml fluid, while that of both base and Base with Triazine fluids are 503 mg H2S/ml and 1666 mg H2S/ml, respectively. The corrosion rate was very small, 0.00060 lb/ft2 after 6 hrs. The test was repeated with the same conditions for 24 hrs and the corrosion rate was found to be 0.00084 lb/ft2 after 24 hrs.

Salaheldin Elkatatny is an associated professor at King Fahd University of Petroleum and Minerals, Petroleum Department. His areas of research include drilling fluid optimization, wellbore cleanup, formation damage, stimulation, wellbore stability, artificial intelligence, and Geomechanics. He has 2 commercialized patents, 5 granted patents and more than 30 filed patents, 60 journal papers and presented more than 100 technical papers.

more information about the research can be found here