COMPARATIVE ANALYSIS OF RICE AND SOYA BEANS HUSK ASH AS PH MODIFIERS IN WATER-BASED MUD

ABSTRACT Drilling fluid additives play an important role in oil and gas well drilling and, in an attempt, to formulate the appropriate mud (be it oil or water based) for any drilling operation, the right additives must be selected and utilized in the appropriate amounts. In this research, laboratory investigation was carried out to determine the pH enhancing property of rice husk ash (RHA) and soybean husk ash (SBHA) in water based mud and the results of their performances were compared to NaOH as the conventional drilling mud pH enhancer. From the results obtained, the pH of RHA decreased from 10.0 to 9.3 (shifting to acidic) while that of SBHA increased from 10.0 to 11.0 (shifting to alkaline). The plastic and apparent viscosities were also examined and both additives showed increase in these properties satisfying the API requirement. Results of density showed that while SBHA slightly increased density of mud from 8.6 to 8.65 ppg, RHA maintained the mud density of 8.6 ppg over the range of amount added. The mud cake thickness was measured and it ranged from 0.5 to 0.75 mm for RHA and from 0.5 to 0.65 mm for SBHA. Lastly, the fluid loss results showed that as amount of each additive increases, the fluid loss for RHA increases while that of SBHA decreases. In conclusion, SBHA performs better as additive in WBM than RHA most especially as pH enhancer.