Gas Slippage in Tight Formations

In order to address the gas slippage for flow through tight formation, with a very low porosity (less than 10%) and permeability in micro-Darcy range, a series of single-phase gas flow experiments were conducted. Two different gases (N2 and He) were used to carry out many single-phase experiments at different overburden and pressure drops and were compared with carbon dioxide (CO2) flow types. The pore size distribution measurements showed the existence of a wide range of pore size distribution. Also, the single-phase gas flow experiments through the core plug, mostly at low pressure, showed Knudsen diffusion type, which is an indication of gas molecules’ slippage at the wall of the pores

Displacement Efficiency in Tight Sandstone Based on Fractional Flow Curve Using Relative Permeability Data

In tight gas sandstone, relative permeability is an essential special core analysis dynamic test that can be used to estimate injectivity, secondary recovery, production rate, reservoir simulation, residual gas saturation, and effective water management. Having about 65% of hydraulic fracturing fluid not to flow back and stay in the reservoir results in having the tight sandstone gas reservoir to involve multi-phase flow, namely water and gas. During the hydraulic fracturing job both imbibition and forcibly imbibition processes take place while during fracturing fluid cleanup and gas production drainage flow becomes dominant. The steady state flooding process was used to measure the relative permeability curves for tight sandstone core sample collected from Travis Peak Formation at a depth of 8707 ft. The measurement process involved the performance of a series of steady state experiments with different gas-water injection ratio. The fractional flow curve has been plotted, based on the measured relative permeability, and used to calculate the displacement efficiency for the flow through such type of tight porous media. The measurement showed relatively high irreducible water saturation (31%) and low residual gas saturation (6%). The measured gas relative permeability decreased slowly at a constant rate with increased wetting fluid saturation. The obtained fractional flow curve does not follow the s-shape behavior observed in conventional reservoir. The obtained results showed that displacement efficiency can be enhanced by increasing water viscosity.    &nbsp

A Critical Review of Alkaline Flooding: Mechanism, Hybrid Flooding Methods, Laboratory Work, Pilot Projects, and Field Applications

Over time, the dependence on oil has increased to meet industrial and domestic needs. Enhanced oil recovery (EOR) techniques in this regard have captured immense growth as EOR is not only used to increase the oil recovery but also to augment the sweep efficiency. Several techniques over the past decades have been used to improve oil recovery with cost-effectiveness. Cost-effective alkaline flooding has been effective for those oil reservoirs with a high total acid number. In this review, the significance of alkaline flooding has been discussed in detail, as well as the features of alkaline flooding in comparison to other modes of flooding. This review entails (1) alkaline flooding, (2) hybrid modes of injection, (3) experimental work, (4) pilot projects, (5) screening criteria, and (6) field applications. The findings of this study can help increase the understanding of alkaline flooding and provide a holistic view of the hybrid modes of flooding

Carbon Dioxide Capture under Low-Pressure Low-Temperature Conditions Using Shaped Recycled Fly Ash Particles

Carbon-capture technologies are extremely abundant, yet they have not been applied extensively worldwide due to their high cost and technological complexities. This research studies the ability of polymerized fly ash to capture carbon dioxide (CO2) under low-pressure and low-temperature conditions via physical adsorption. The research also studies the ability to desorb CO2 due to the high demand for CO2 in different industries. The adsorption–desorption hysteresis was measured using infrared-sensor detection apparatus. The impact of the CO2 injection rate for adsorption, helium injection rate for desorption, temperature, and fly ash contact surface area on the adsorption–desorption hysteresis was investigated. The results showed that change in the CO2 injection rate had little impact on the variation in the adsorption capacity; for all CO2 rate experiments, the adsorption reached more than 90% of the total available adsorption sites. Increasing the temperature caused the polymerized fly ash to expand, thus increasing the available adsorption sites, thus increasing the overall adsorption volume. At low helium rates, desorption was extremely lengthy which resulted in a delayed hysteresis response. This is not favorable since it has a negative impact on the adsorption–desorption cyclic rate. Based on the results, the polymerized fly ash proved to have a high CO2 capture capability and thus can be applied for carbon-capture applications

Rigorous review of electrical submersible pump failure mechanisms and their mitigation measures

Artificial lift is a vital part of the life of many oil wells worldwide. Using several artificial lift methods can prolong the life of the wells and increase oil recovery significantly. One of the most applied artificial lift methods nowadays is the electrical submersible pump (ESP). This artificial lift method has the ability to handle large volumes of hydrocarbons and is applicable under many conditions in both offshore and onshore reservoirs. Even though ESP has been applied extensively for many years, it still suffers from many failures due to electrical, mechanical, and operational problems associated with the ESP downhole assembly. Understanding the main reasons behind ESP failures and how to rapidly and effectively avoid and mitigate these failures is imperative to reduce cost and damage and improve operational and rig-personal safety. This research performs a comprehensive review on ESP failure mechanisms and analyzes these failures in order to determine the optimum conditions to operate the ESP. This can help minimize and avoid these failures. Also, should these failures occur, the research proposes several mitigation methods for each failure based on analysis of different field cases worldwide

A comprehensive review of sucker rod pumps’ components, diagnostics, mathematical models, and common failures and mitigations

In many oil reservoirs worldwide, the downhole pressure does not have the ability to lift the produced fluids to the surface. In order to produce these fluids, pumps are used to artificially lift the fluids; this method is referred to as artificial lift. More than seventy percent of all currently producing oil wells are being produced by artificial lift methods. One of the most applied artificial lift methods is sucker rod pump. Sucker rod pumps are considered a well-established technology in the oil and gas industry and thus are easy to apply, very common worldwide, and low in capital and operational costs. Many advancements in technology have been applied to improve sucker rod pumps performance, applicability range, and diagnostics. With these advancements, it is important to be able to constantly provide an updated review and guide to the utilization of the sucker rod pumps. This research provides an updated comprehensive review of sucker rod pumps components, diagnostics methods, mathematical models, and common failures experienced in the field and how to prevent and mitigate these failures. Based on the review conducted, a new classification of all the methods that can fall under the sucker rod pump technology based on newly introduced sucker rod pump methods in the industry has been introduced. Several field cases studies from wells worldwide are also discussed in this research to highlight some of the main features of sucker rod pumps. Finally, the advantages and limitations of sucker rod pumps are mentioned based on the updated review. The findings of this study can help increase the understanding of the different sucker rod pumps and provide a holistic view of the beam rod pump and its properties and modeling