Green approach in water-based drilling mud design to increase wellbore stability

Scientific paper - Original scientific paper

• Author: Igor Medved
• Author: Nediljka Gaurina-Međimurec
• Author: Borivoje Pašić
• Author: Petar Mijić
• Author's institution: University of Zagreb; Faculty of Mining, Geology and Petroleum Engineering; (Department of Petroleum and Gas Engineering and energy)
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mining, Petroleum and Geology Engineering

Abstract (english)

Wellbore instability is one of the most serious problems that can occur during drilling, mainly during drilling oil or gas wells through rocks that contain a higher proportion of clay, such as shales. To prevent wellbore instability, oil companies apply different approaches to strengthen wellbore walls, and use different shale swelling inhibitors. The aim of this research was to apply a green approach and the concept of the circular economy in mud design, and to determine whether mandarin peel powder, which is a waste material, can be used as an inhibitor of shale swelling. For that purpose, pellets consisting of bentonite and quartz in a 50:50 ratio were prepared using a compactor, and bentonite-based drilling mud (BM) with and without mandarin peel powder in concentrations of 0.5, 1, 1.5 and 2% by volume of water. The swelling of quartz–bentonite pellets after 2 and 24 h in each drilling-mud sample was determined at room temperature and 90 °C using a linear swell meter. On the basis of laboratory research, we concluded that increasing the concentration of mandarin peel powder reduces pellet swelling. By adding mandarin peel powder particles between 0.1 and 0.16 mm to the base mud at a concentration of 2% by volume of water, the following was achieved: 44% reduction in API filtration, 61.54% reduction in PPT filtration, 45% reduction in pellet swelling after 24 h at room temperature, and 48.6% reduction of pellet swelling after 24 h at 90 °C.

• Keywords (english): waste mandarin peel; wellbore instability; drilling mud; quartz–bentonite pellet; swelling; mud filtration
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Applied Sciences
• Numbering: vol. 12, no. 11, 5348
• e-ISSN: 2076-3417
• DOI: https://doi.org/10.3390/app12115348
• URN:NBN: urn:nbn:hr:169:503139
• Publication: 2022-05-25
• Document URL: https://www.mdpi.com/2076-3417/12/11/5348
• Type of resource: Text
• Access conditions: Open access
• Created on: 2023-01-27 14:09:23