A reliable strategy for slug flow attenuation in pipeline-riser systems

Oil and gas activities across the globe now take place deep offshore. To operate in this harsh environment, there are numerous challenges. These can be in the form of high cost of production, space constraints, operational and technological demands. The co-transportation of oil and gas in same pipeline is one of the operational and technological approaches adopted in the industry to meet the transportation of produced crude. This approach comes with its attendant flow assurance difficulties. Slugging is one of such problems which can constitute operational hitches resulting in production reduction and sometimes eventual plant shutdown. Existing attenuation techniques are limited in various ways. Therefore, seeking a reliable solution to this problem is highly desired.In this study, an experimental study of multiple techniques for slug attenuation was attempted. A passive device-the intermittent slug absorber, topside choking and topside separator were investigated. The results show that a combination of the methods proves to be more effective compared to individual techniques. A significant reduction in riser- base pressure of up to 39% was achieved. This is advantageous and translates to an increase in oil recovery. Thus, the proposed strategy helps to achieve system stability and improved production at a lower cost

Characteristics of horizontal gas-liquid two-phase flow measurement in a medium-sized pipe using gamma densitometry

Two-phase flows are common occurrences in many industrial applications. The understanding of their characteristics in industrial piping systems is vital for the efficient design, optimization, and operation of industrial processes. Most of the previous experimental studies involving the use of gamma densitometers for holdup measurements in air-water mixtures are limited to smaller diameter pipes (generally regarded as those with < 50 mm in nominal diameter). Further, very few literature report experimental data obtained using gamma desitometers. This paper presents an application of a gamma densitometer in the measurement of two-phase flow characteristics in an intermediate diameter pipe (nominal diameter between 50 mm and 100 mm). Scaled air-water experiments were performed in a 17-m long, 0.0764-m internal diameter horizontal pipe. Liquid superficial velocity ranged between 0.1–0.4 m/s while gas superficial velocity ranged from 0.3 to 10.0 m/s. The measured parameters include liquid holdup, pressure gradient, flow pattern, and slug flow features. The flow patterns observed were stratified, stratified-wavy, plug, slug, and annular flows. Plug and slug flow patterns showed good agreement with established flow pattern maps. Furthermore, the slug translational velocity was observed to increase with increasing mixture velocity, as reported by previous authors, hence establishing the reliability of the instrumentation employed. The slug body length was also measured using the gamma densitometer and was found to be within the range 24–36D with a mean length of 30.6D

Evaluation of Socio-Economic Factors Influencing Information Accessibility among Farmers in Oyo State, Nigeria

This study evaluated the socio-economic factor influencing information accessibility in Oyo State. Primary data were obtained from 50 farmers with the aid of structured questionnaire. The result showed that, 100% of the farmers got their information from Radio, 90% TV, 20% Friend, 30% Non-Governmental Organisation and 26% got information through their ADP. Therefore, majority of the farmers obtained their agricultural information through the Radio which indicates that information plays a vital role in the life of the farmers, especially in fertilizer application, pest and disease in crop production and economic development. The determinants of factors influencing information were age, education and extension contact. Therefore, the study recommends that farmers in Oyo State should be encouraged financially to have access to information to enhance crop production. Keywords: Determinant, Socioeconomic factor, agricultural information, extension contact

Test of QED in e+e- -->gammagamma at LEP

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