Aloe Vera Mucilage as Drag Reducing Agent in Oil-Water Flow

Drag reduction is the deliberate reduction of the frictional pressure drop in flow systems by the addition of heavy molecular weight polymeric materials as well as other means such as pipeline modifications. Environmentally friendly and cheaper heavy molecular weight polymeric drag reducing agents (DRAs) has become a necessity in the transportation of fluids particularly in the oil and gas industry. However, very few reports exist on the potentials of natural polymers such as extracts from the Aloe Vera plant. In this study, the effects of Reynolds number and polymer concentration on the drag reduction effectiveness of Aloe barbadensis miller were tested. An experimental flow facility using unplasticized  Polyvinylchloride (uPVC) pipe of 12 mm ID was constructed with diesel (density = 832 kg/m3, dynamic viscosity = 1.664 mPa.s at 25°C) and water (density = 1000 kg/m3, dynamic viscosity = 0.891 mPa.s at 25°C) as test fluids. Drag reduction as a function of Aloe polymer concentration in the range 50 ppm to 500 ppm and Reynolds number 20000<Re<90000 were investigated by comparing the U-tube manometer pressure drop readings with and without aloe polymer. The pressure drop difference expressed as a percentage of the pressure drop without aloe polymer is termed drag reduction and was used to demonstrate the effectiveness of the Aloe Vera extracts or polymer as a DRA. In single phase horizontal (water) flow, a maximum drag reduction of 64% (U = 4.67 m/s) was measured, while in multiphase horizontal flow, a maximum drag reduction of 53.80% (α = 25%, Um = 4.67 m/s) was measured. Furthermore, measurements showed that pipe inclination had minimal effect on the drag reduction achieved. It was deduced that Aloe Vera mucilage can be used as a drag reducing agent in oil-water flows for Reynolds number below 63,00

A stochastic predictive control approach to project risk management

This work shows a control policy based on MPC and applied to project risk management. MPC has been applied due the properties that presents such as the easy constraint treatment or the extension to multivariable case. The control actions are the mitigation actions to execute in order to reduce the risk exposure. Stochastic variables have been introduced to model the uncertainties of risk impacts. Integer variables are involved in the optimization problem modelling the mitigation actions

Computational Fluid Dynamics Study of Flow within a Double Gap Cylinder

Drag reduction is a field that has been focused on these days, especially in certain fields like the oil and gas industry. Drag reduction agents are used to assist in drag reduction. To analyse the performance of drag reduction agents, rheometers with the double gap cylinder designs are preferred. However, the usage of double gap cylinder in assessing drag reduction has been slightly inaccurate. This is due to a secondary flow formed in the instrument during the assessment, which cause overflow of the fluid when the rotor is rotated up to a certain speed. This secondary flow is closely related to Taylor-Couette flow. Thus, the objective of this study is to investigate the flow behaviour of the fluid in the double concentric cylinder under specific parameters chosen. In order to do so, computational fluid dynamics would be used to the study the flow. Simulation is done using ANSYS Fluent. The geometry model is constructed and exported into Fluent, prior to the appropriate solution setups. Results were analysed though contour of velocity and graphs as well. It is found out that the instabilities starts to form in the region of angular velocities of 13-14 rad/s. Furthermore, the instabilities tend to grow with higher angular velocity applied. Results also shown that there is presence of spillage of water out from the geometry. Therefore, the instabilities in the flow that causes the secondary flow in the double gap cylinder are simulated. Nevertheless, it is recommended that simulation setup is further refined together with other parameters to be assessed further

Effect of Drag Reducing Agent on Water injection Well

Drag reducing agents (DRA) has been used to inject the produced water into the producing reservoir and to inject produced water into an abandoned reservoir or aquifer. By introducing DRA into water injection well, the differential pressure drop in the water injection tubing is reduced thereby increasing water injection capacity. However, DRA is also suspected to bring about some damage on the reservoir and there are very less study being conducted to look into the effect of DRA on the formation, especially the near wellbore zone. This project will be looking more into the matter by evaluating the effect of commercial drag reducing agents on water injection well. This project will utilize the coreflooding technique and low range of core permeability around 30md and below will be used. The test will be conducted at standard temperature using a polymer type DRA.A fix concentration of 50ppm will be used for the DRA and the solution is to be mechanically degraded under high shear rates before injected into the core to simulate field situation. Different injection rate which will be 1cc/min and 5 cc/min and commercial drag reducing agents will be used to test their relationship with reduced permeability. Reverse flow will be conducted to restore the permeability

Laboratory evaluation of the drag reduction additives effectiveness

This study describes the laboratory evaluation methodology of the drag reducing effect of block poly-1-octene. Poly-1-octene, synthesized in our laboratory was chosen as an object of the present study. To confirm the nature and the structure of the obtained polymer its FTIR spectrum was registered. The molecular mass was determined by viscosimetric method using an Ubellode viscosimeter, the obtained value was 5.22×106. Hydrodynamic testing of poly-1-octene solutions has been performed using a capillary rheometer of our own construction for the quantitative estimation of the polymer's drag reduction capability. We introduce criterion for a quantitative estimation of a polymer hydrodynamic drag reducing capability. This is a semi-effect concentration С1/2 that can be determined using a dependence of DR on the concentration

High-viscosity biphasic flow characterization in a pipeline: application to flow pattern classification and leak detection

Pipeline systems play an essential role in the oil industry. These systems connect ports, oil fields, refineries, and consumer markets[104]. Pipelines covering long distances require pumping stations, where products are propelled to the next pumping station, refinery, or deposit terminal, thus traveling through most of the country. The product considered in this research work is crude oil. It is usually transported with a combination of crude oil with viscosity reducers (DRA, drag reducer agent) and oil with gas in onshore/offshore pipelines. This mode of transport is efficient for large quantities and large product shipment distances. Problems may arrive when a leak occurs. In major incidents, large scale damage to humans and the environment is possible. Then, this research addresses the problem of how to detect the leak earlier to reduce the impact in the surrounding areas and economic losses, considering five research topics taking into account that the products inside the pipeline are water-glycerol and gas-glycerol mixtures (simulating oil-DRA and oil-gas in the laboratory test apparatus). The first research topic presents a mathematical model to describe the flow of a mixture of water and glycerol in pressurized horizontal pipelines, which emulates the mixture of heavy oil and a viscosity reducer. The model is based on the mass and momentum conservation principles and empirical correlations for the mixture’s density and viscosity. The set of partial differential equations is solved using finite differences. These equations were implemented in a computer platform to be able to simulate a system. This simulation platform is a tool to simulate leak cases for different fractions of water and glycerol to evaluate algorithms for leak detection and localization before their implementation in a laboratory setting.DoctoradoDoctor en Ingeniería Mecánic

Safe & Reliable Ethanol Transportation & Storage Technology Roadmapping Workshop Summary Results

Biofuels, especially ethanol, are gaining attention as partial replacements of imported fuels and to offset CO2 emissions from the burning of fossil fuels. Consequently, legislation is being proposed to mandate a significant increase in ethanol usage as a fuel over the next 20 years. The planned wide-spread usage of ethanol will require an efficient and reliable transportation and storage system that encompasses both the existing infrastructure and new construction. The fuels are currently being transported by rail, truck, and ship; however, in order to economically transport biofuels from producers to users on a large scale, safe and reliable transportation by pipeline is necessary. Prior industry experience and research has shown that stress corrosion cracking (SCC) can initiate in some fuel-grade ethanols. Detailed laboratory studies indicate that primary factors contributing to the initiation of SCC include the presence of dissolved oxygen and other contaminants, including pre-existing corrosion products, and the corrosion potential of the fuel. The source of the fuel (e.g., corn, sugar cane), the gasoline-to-ethanol blend ratio, and handling of the fuel from production to end-user delivery influences the significance of these factors as well as the operational and maintenance protocols to be applied for safe transportation of the fuel by pipeline. In addition to pipeline reliability, quality of the fuel as it travels down the pipeline to the end-user must be assured. Finally, the effect of ethanol on other metallic and non-metallic components needs to be evaluated. In an effort to solicit broad perspectives on the activities needed to enhance the safe and reliable transportation of ethanol, a Road Mapping meeting was held in Dublin, Ohio on October 25 and 26th, 2007 with the support of the Association of Oil Pipe Lines (AOPL), American Petroleum Institute (API), U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration (PHMSA), and Pipeline Research Council International (PRCI). The workshop was organized to bring together experts with diverse perspectives on ethanol to identify: • Gaps in knowledge, current industry practices, and future industry needs. • Technical challenges related to pre-commissioning through delivery to the end user. • Focused areas of study to support the development of solutions for knowledge gaps and technical challenges and guidelines for implementation. • Where and how the study can be aligned with related industry and regulatory activities. The workshop consisted of a series of plenary presentations followed by detailed breakout sessions on four topics: Ethanol Sources and Quality Issues; Pipeline Integrity; Pipeline Operations; and Standards, Guidelines, and Training. Each of the detailed breakout sessions discussed the status of knowledge today, prioritized the gaps in knowledge and barriers that must be overcome, and identified specific activities that should be undertaken to address the gaps. This document provides a summary of the workshop findings

Issues in Infrastructure Development Today: The Interlinkages

Brings out the issues in infrastructure development in India linking market failure, policy, regulation, and privatisation in India c. 2000. Is the lead article in the India Infrastructure Repor