Bioethanol is an important biofuel produced from biomass and is generally regarded as the future of fuels. This research was carried out for the main purpose of determining the optimum process conditions required for maximum bioethanol yield from the pulp of local sweet potato. The variety of potato used in this research is the Nigerian sweet potato (Ipomoea Batatas (L.) Lam) containing high amount of starch and the experiment was carried out with the use of Baker’s Yeast (Saccharomyces cerevisae) as the biocatalyst. In this study, the effect of acid concentration for hydrolysis, pH and fermentation period was examined. The sweet potato pulp was hydrolyzed using dilute sulphuric acid solutions of 0.5M, 1.5M and 2.5M and heated for 30 minutes at 100 ℃ yielding 0.9% (v/v) reducing sugar for fermentation. The hydrolysates were then subjected to fermentation at different pH values for different fermentation periods of 2, 3.5 and 5 days respectively. The pH values ranged from 4.5 to 6.5, an increment of 1.0 was used during the examination of pH with 1.0 M sodium hydroxide solution (NaOH) used for adjustment. The rate of bioethanol production was seen to increase as the pH and fermentation periods increased with the exception of the fermenting cultures of pH of 6.5. The maximum bioethanol yield of 13.40 ml, equivalent to 3.350% (v/v), was gotten from the hydrolysate obtained using the dilute acid of concentration 0.5M and left to ferment for 5 days at a pH of 5.5.

Crude oil, the world’s major source of energy, is obtained from the earth as a Newtonian fluid and needs to be transported to refineries for further processing. Pipeline transport has proven to be the most efficient, environmental-friendly and cost effective of all modes of crude oil transportation from subsea production sites. However the formation and deposition of waxes (mainly paraffinic and asphaltenic components) along pipelines remains one of the greatest flow assurance problem in the petroleum industry. This is aided by attainment of wax appearance temperature (WAT), the crude’s hydrocarbon contents and rheological properties, and the production conditions amongst others. The deposited waxes clog the pipeline, reduces the flow diameter, converts the behavior of the fluid from Newtonian to non-Newtonian, decreases throughput, causes more work on pumps and other process equipment, increases energy consumption, and ultimately raises the cost of production thereby decreasing profits. It also leads to several downtimes and in extreme cases can cause permanent shut down of facilities. Several studies have been done to understand the nature of crude oil waxes and the various techniques for solving this problem. This paper takes a critical look at crude oil and reviews the current state of research into the causative factors, deposition mechanisms and remediation methods including the thermal, mechanical, biological and chemical techniques. At the end there is a conclusion and further research on the use of biological techniques (microorganisms) has been advised herein.