Characteritization of Bio-Oil from Tectona Grandis as a Potential Scale Inhibitor

Abstract

Abstract Calcium carbonate scales cause costly flow assurance problems in flowlines during petroleum production. Previous efforts to mitigate this problem using different chemical inhibitors though successful have resulted in environmental pollution during disposal. This study was designed to investigate the potential of bio-oil synthesized from Tectona grandis as an inhibitor to replace the conventional ones. Tectona grandis was obtained from Ibadan sawmill, Oyo state, Nigeria and characterized using Energy Dispersive X-Ray (EDX) analytical technique. Data generated by EDX analysis showed elemental composition of 78% carbon and 22% of other elements including nitrogen and oxygen. Tectona grandis was pyrolyzed at 5500C, a heating rate of 0.50C/sec, and a running time of 4 hours. 45.1% of the mixture of water and oil were collected and separated into phases in a centrifuge while the gasses were vented. The bio-oil was distilled at 120°C and analyzed using FTIR spectrometry. Spectra analyses showed the presence of -COOH and -CONH2 which are essential in the inhibition of calcium carbonate scale. With the help of a newly fabricated testing-rig system, calcium carbonate scales were formed by mixing equal mole of calcium chloride and sodium carbonate at the temperature range of 25-58°C and flow rates range of 8-15 ml/min, with/without inhibitor from 0, 5 g/l of maleic acid and 5 g/l of newly synthesized inhibitor. The mass of the calcium carbonate and the induction time was measured by the weighing balance and the conductivity meter respectively. For all of the experiments, the presence of maleic acid and newly synthesized inhibitor delayed the induction time by at least 10 mins and reduced the weight of calcium carbonates formed by at least 20%. Also, the mass of calcium carbonate scale formed at all the experiments showed less weight when newly synthesized inhibitor was used compared to when maleic acid inhibitor was used showing the effectiveness of the newly synthesized inhibitor over maleic acid. Therefore, this study shows high promise wood-based distilled oil as a potential calcium carbonate scale inhibitor and provides future direction for further studies.