Green Approach in Water-Based Drilling Mud Design to Increase Wellbore Stability

Abstract

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.

Acylated Inulin as a Potential Shale Hydration Inhibitor in Water Based Drilling Fluids for Wellbore Stabilization

“…Moreover, the toxicity of the three acylated inulins is related to the alkyl chain length, as the C14-inulin clearly shows higher toxicity than the C10-inulin. However, the EC 50 values of acylated inulins are still higher than standard values (>30,000 ppm, a concentration is considered non-toxic), signifying that they are non-toxic [26]. Furthermore, considering that common usage concentrations are between 10,000-30,000 ppm, all three of the acylate inulin SHIs can be regarded as non-toxic.…”

“…Certain natural materials and their derivatives exhibit great potential for inhibiting shale hydration. Several studies have revealed that natural surfactants can potentially serve as SHIs [26]. Moslemizadeh et al [27] found that glycyrrhizin, extracted from the glycyrrhiza glabra root, has good inhibitory properties.…”

A Magnetic Surfactant Having One Degree of Unsaturation in the Hydrophobic Tail as a Shale Swelling Inhibitor

“…Albeit, OBM are more efficient, they are less preferred due to their toxicity, high cost, and dangers they pose to the environment [ 6 ]. With the numerous strict regulations currently put in place to combat issues associated with climate change, safe disposal of drilling cuttings from OBM becomes an arduous task [ 7 ]. On the other hand, WBM are environmentally benign, have ease of preparation, and cost less [ 8 , 9 ].…”

Sensitivity Analysis of Wellbore Mud Pressure towards Anisotropic Shale Properties, Pore Fluid Pressure and Far Field Stresses

“…In these depleted fields, new wellbores must be drilled for gas injection operations. Consequently, drilling operation in shale is still a matter of concern [8][9][10][11][12][13][14][15][16][17].…”