In previous studies, it has been found that the Nigerian bentonite is deficient in terms of its fluid loss and rheological properties which includes yield point. Also, due to its high calcium content and low sodium content as opposed to foreign bentonite, it does not meet the API standard of drilling. This research was carried out to beneficiate the Nigerian bentonite as regards its fluid loss properties, rheological properties and wellbore stability. Snail shell is seen as waste substance in Nigeria, and Mucuna solannie on the other hand is a local major food supplement in Nigeria and is found in large quantities. The elemental and oxide compositions of the snail shell and Mucuna solannie were determined through scanning electron microscope and X-ray diffraction measurements, respectively. The additives were used to beneficiate the Nigerian bentonite, and the test result proved that at considerable concentrations of the additives, the Nigerian bentonite was able to compete with foreign bentonite and also met API specifications. Both additives contain high concentrations of nanoparticles and inhibitive calcium and potassium for wellbore stability. Beneficiated Nigerian bentonite also proved to be viable economically when compared with foreign bentonite.
In recent years, research using biomaterials in drilling fluid design has thrown light on their biodegradability, availability and low cost. Apart from these, they have in some cases shown properties superior to those of synthetic materials. This research assessed Mucuna solannie as a fluid loss control agent, looking at its fluid loss, filter cake quality, rheology and comparing them with those of Sodium Asphalt Sulfonate, a commonly used drilling mud additive. It assessed the additives at varying concentrations of 2 ppb, 4 ppb, 6 ppb and 8 ppb. The results obtained were filtrate volumes of 5.5 against 4.8 at 2 ppb, 5.0 against 4.5 at 4 ppb, 4.5 against 4.2 at 6 ppb, and 4.1 against 3.8 at 8 ppb, all at 30 min. Field standard value is 5.0 ml fluid loss. Filter cake thickness was1mm for all concentrations of Mucuna solannie. On rheology, plastic viscosity, yield point and yield stress were 27cP against 28cP, 19Ib/100ft2 against 19Ib/100ft2, and 5Ib/100ft2 against 6Ib/100ft2, showing slight difference in their rheological properties.
Due to the difficulty that the compressive strength of cement slurries formulated with bentonite are not stable at elevated temperature conditions, in addition to other properties at high temperatures, Mucuna solannie commonly known as “Ukpo” was examined as an alternative. API standard procedures were employed throughout the laboratory measurements to determine overall rheological properties, compressive strength, thickening time, and free water of the extenders both at 150 °F (65.6 °C) and 200 °F (93.3 °C) BHCT. Mucuna solannie results gave compressive strength at 24 h as 952 psi (6.56E+6 Pa) and 900 psi (6.21E+6 Pa), free water values of 0 and 0.2 ml, yield point values of 67 lb/100ft2 (32.08 Pa) and 66 lb/100ft2 (31.60 Pa), and 10 min gel strength of 16 lb/100ft2 (7.66 Pa) and 22 lb/100ft2 (10.53 Pa). Bentonite additive gave 24 h compressive strength as 620 psi (4.27E+6 Pa) and 565 psi (3.9E+6 Pa), free water of 4.4 and 4.8 ml, yield point of 56 lb/100ft2 (26.81 Pa) and 46 lb/100ft2 (22.02 Pa), and 10 min gel strength of 16 lb/100ft2 (7.66 Pa) This showed that Mucuna solannie is a better alternative cement extender than Bentonite, especially where optimum free water and compressive strength are needed. Although it is found to be lacking in efficient plastic viscosity and thickening time, it can be resolved by the use of additives such as dispersant and accelerator to complement its properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.