UISpace
Welcome to UISpace, The University of Ibadan Institutional Repository. A collection of theses, articles, books, videos, images, lectures, papers, data sets and all types of digital content originating from the University of Ibadan Nigeria. This repository is managed by the Kenneth Dike Library University of Ibadan, Nigeria.
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The prospect of using modified local starches from cocoyam and wheat starches as fluid loss material in a water - based drilling
(Nigerian Institute Of Industrial Engineers, 2017) Akintola, S. A.; Ogundipe, M.
As an oil producing nation, Nigeria embarks on substantial drilling activities. The additives used for these activities are all imported as a result there is need to reduce the over dependency on foreign additives this has necessitated the sourcing locally for suitable substitute. During drilling, adequate filtration control is essential to prevent drilling problems such as excessive torque and drag; differential pressure sticking; borehole instability; and formation damage. This study was aimed at a comparative analysis of the use of wheat starch and cocoyam chemically modified with ammonium phosphate and sodium acetate as suitable fluid loss additives in a water-based mud. The filtration properties of a water- base fluid formulated with variable quantities of the chemically modified starch were determined using the recommended standard API practice at different conditions of temperatures with Carboxymethylated Cellulose CMC used as control. Using Eviews 7, the statistical analysis showed drilling fluid formulated with starches treated with sodium acetate had a fluid loss value in the range of 4.0 - 8.9 mls, while those from starches modified with ammonium phosphate had a fluid loss of 4.3 - 8.3 mls; although, these values were lower than 9.1 - 11.1 mls for CMC formulated mud, the results show that mud sample treated with modified wheat starch and cocoyam starch can significantly reduce fluid loss in a water based drilling mud, thereby confirmed that polymer can be used as fluid loss control agent in the mud system.
Conversion coating pretreatment enhances pipeline integrity
(Open Science, 2018) Makanjuola, O.; Adediran, A. A.; Ogunsemi, B.; Akintola, S. A.; Ebitei, C.
It is necessary to coat both the internal and external surfaces of pipelines which transport different types of fluids that are usually contaminated with various percentages of aggressive corrosives. Pipelines pass through various terrains and highly challenging environments hence the need for both internal and external coatings to prevent corrosion and its adverse effects. In order to improve on the longevity of pipelines and the adhesion of the coating system, it is preferable to conversion coat blasted surfaces prior to application of any coating system. Improvements in pipeline coatings applications and the often neglected chromating procedure prior to coating application have been highlighted. This will prolong the lifespan of pipeline networks and secure these strategic assets from being a source of both materials and human resources drain pipes. However, the use of corrosion resistant alloys as internal lining for carbon steel pipes in the petroleum/gas industry is fast gaining recognition.
Prediction of generalised and localised Carbon steel corrosion using improved Norsok and Papavinasam Models
(Sciencedomain International, 2017) Falode, O. A.; Akintola, S. A.; Akinlade, I. A.
In this study, Norsok and Papavinasam models have been improved so as to reduce the model limitations. The Norsok model was improved by accounting for 3 phase flow in calculating the wall shear stress and correcting for oil wetting and formation of protective layers in steel pipes during hydrocarbon transportation while the Papavinasam model was improved by using the Weibull distribution to account for time effect in corrosion predictions. The corrosion rates predicted fairly agreed with the field values. The improved models are user friendly and readily available and thus applicable for corrosion studies in the oil and gas industry.
The prospect of using palm wine as a fluid loss control agent in water based drilling mud
(Avanti Publishers, 2016) Akintola, S. A.; Isehunwa, S. O.; Oboh, S. M.
The need to advance and project the use of local materials as suitable drilling fluid additive in the oil and gas industry in Nigeria led to the research on the possible use of palm wine and potash as additives in a water base drilling mud. A comparative study of these local materials (palm wine and potash) with imported foreign materials (lignite and caustic soda) as control were used in investigating the properties of a water base drilling fluid. A laboratory investigation of the effects of temperature and aging time on the properties of water-base drilling fluid is made with Fann Model 800 High Temperature and a High Pressure (HTHP) Viscometer, according to the API recommended standard practice. The results obtained showed similarity in the drilling fluid’s rheological and filtration properties; mud weight and pH values for both local and foreign additives. The result from the mud sample prepared from the palm wine and potash had apparent viscosity, plastic viscosity and yield point decreasing steadily with increase in temperature for all aging time just as shown with the control sample, while the aging effect diminishing as the aging time increases. The potash was seen to have increased the mud pH from 7.0 to 12.9 pH units. The results, shows that both palm wine and potash can be used as suitable in water base drilling mud additive.
Deconvolution and interpretation of well test data ‘masked’ by wellbore storage in a buildup test
(American Journal of Engineering Research, 2015) Akintola, A. S.; Oriji, A. B.; Duru, K. M.
When a well test contains a series of different flow rates, or a continuously varying flow rate, the combination of the pressure transients due to varying flow rate is called convolution. while deconvolution means removing a distorting effect upon the variable of interest. This paper is on the study of an analytical technique that can be used to explicitly deconvolve wellbore storage distorted well test data using pressure data and the flow rate. Then to determine the reservoir properties from this deconvolved well test data by using the conventional well test interpretation methods. Also the comparison of the material balance deconvolution method results with the β-deconvlolution method result were carried out and then used to determine which method was a better deconvolution tool. The results showed that the material balance deconvolution technique performed very well with minor discrepancies and gave better estimation of the reservoir parameters.