Geochemical Investigation of CO2 Injection in Oil and Gas Reservoirs of Middle East to Estimate the Formation Damage and Related Oil Recovery

The injection performance of carbon dioxide (CO2) for oil recovery depends upon its injection capability and the actual injection rate. The CO2–rock–water interaction could cause severe formation damage by plugging the reservoir pores and reducing the permeability of the reservoir. In this study, a simulator was developed to model the reactivity of injected CO2 at various reservoir depths, under different temperature and pressure conditions. Through the estimation of location and magnitude of the chemical reactions, the simulator is able to predict the effects of change in the reservoir porosity, permeability (due to the formation/dissolution) and transport/deposition of dissoluted particles. The paper also presents the effect of asphaltene on the shift of relative permeability curve and the related oil recovery. Finally, the effect of CO2 injection rate is analyzed to demonstrate the effect of CO2 miscibility on oil recovery from a reservoir. The developed model is validated against the experimental data. The predicted results show that the reservoir temperature, its depth, concentration of asphaltene and rock properties have a significant effect on formation/dissolution and precipitation during CO2 injection. Results showed that deep oil and gas reservoirs are good candidates for CO2 sequestration compared to shallow reservoirs, due to increased temperatures that reduce the dissolution rate and lower the solid precipitation. However, asphaltene deposition reduced the oil recovery by 10%. Moreover, the sensitivity analysis of CO2 injection rates was performed to identify the effect of CO2 injection rate on reduced permeability in deep and high-temperature formations. It was found that increased CO2 injection rates and pressures enable us to reach miscibility pressure. Once this pressure is reached, there are less benefits of injecting CO2 at a higher rate for better pressure maintenance and no further diminution of residual oil

Hydromagnetic Falkner-Skan flow of Casson fluid past a moving wedge with heat transfer

AbstractNumerical solutions are carried out for steady state two dimensional electrically conducting mixed convection flow of Casson fluid along non-isothermal moving wedge through porous medium in the presence of viscous dissipation and heat generation/absorption. The governing partial differential equations, subject to boundary conditions are transformed into ordinary differential equations using similarity transformations. The transformed equations are then solved numerically by Keller-box method. To check the validity of present method, numerical results for dimensionless local skin friction coefficient and rate of heat transfer are compared with results of available literature as special cases and revealed in good agreement. The influence of pertinent parameters on velocity, temperature profiles, as well as wall shear stress and heat transfer rate is displayed in graphical form and discussed. It is found that fluid velocity increases with increase of Eckert number in case of assisting flow, while it decreases in case of opposing flow. It is also noticed that heat generation/absorption parameter influence fluid velocity and temperature significantly. A significant result obtained from this study is that heat transfer rate reduces with increase of Prandtl number in the presence of viscous dissipation effect. Also, increasing values of Eckert number have no effects on force convection flow

Thermochemical Modeling of Metal Composition and Its Impact on the Molten Corium–Concrete Interaction: New Insights with Sensitivity Analysis

The characterization of molten corium–concrete interaction (MCCI) has increasingly become a cause of concern because, in the case of a severe nuclear accident, the core could meltdown and release radiation into the environment. The objective of this study was to determine the thermochemical impact of metal content in the corium and analyze the effect of corium metal content on ablation depth, corium temperature, its viscosity and surface heat flux, and production of hydrogen, carbon monoxide, and carbon dioxide. The governing heat transfer equations were solved while considering the various thermochemical reactions in the existing numerical code in a comprehensive way. The developed MCCI model in CORQUENCH was validated against the data available in the literature. Our findings showed that the composition of corium, especially its metal content, has a noticeable effect on mitigating or aggravating the ablation depth and nuclear reactor integrity. We observed that during molten corium–concrete interaction, zirconium plays a significant role and its presence can increase the ablation depth exponentially from 18.5 to 139 cm in the investigated case study. It was found that the presence of zirconium in the corium instigated various thermochemical reactions continuously, and thus the injected water, instead of quenching the molten corium, enhances the temperature by facilitating exothermic reactions. Additionally, due to the presence of zirconium, the production of hydrogen and carbon monoxide increases by 45 and 52 times, respectively and the generation of carbon dioxide becomes zero because the zirconium reacts with carbon dioxide continuously, converting it to carbon monoxide

MHD Mixed Convection Flow of Casson Fluid over a Moving Wedge Saturated in a Porous Medium in the presence of Chemical Reaction and Convective Boundary Conditions

This work concerned to hydromagnetic mixed convection flow of Casson fluid over a wedge. It is assumed that the wedge is moving inside a porous medium. The effects of chemical reaction, slip and convective boundary conditions at velocity, temperature and concentration walls are also considered. The governing partial differential equations are converted into ordinary differential equations using similarity transformations, and then solved by implicit finite difference scheme. Comparisons with the existing literature are performed and good agreement is achieved. The influence of physical parameters on flow fields are illustrated graphically. It is observed that the velocity rises with the increment in Casson fluid parameter and magnetic parameter. It is also noticed that thickness of thermal boundary layer grows with the increase of radiation. The skin friction coefficient enhances with the increase of porosity parameter while reduces as Casson fluid and moving wedge parameters increase. Increase in heat and mass transfer rate is noticed to be enhanced with the increase in radiation and chemical reaction parameters, respectively

FREQUENCY OF FUNGAL MYCOFLORA ON RICE

Introduction: Rice (Oryza sativa L.) is the second best essential cereal crop of the world as well as of Pakistan. There are various fungal pathogens that attack on rice and cause various rice diseases. Methods: Therefore, the present experiments were done to isolated different fungi associated with seeds, stems, and leaves of commercially grown rice varieties and of mainly isolated species. Results: Several fungi, namely, Magnaporthe oryzae, Curvularia lunata, Helminthosporium oryzae, Fusarium moniliforme, Alternaria alternata, Nigrospora oryzae, and Aspergillus niger were isolated from seeds, stems, and affected leaves of rice. Conclusion: In our research, the frequency of fungal mycoflora on rice has been calculated and the maximum isolates of Fusarium spp. have been found

DIGITALISASI GUA PRASEJARAH BERGAMBAR DI KAWASAN KARST MAROS-PANGKEP: STUDI KASUS LEANG LAMBATORANG KABUPATEN MAROS

The Maros and Pangkep areas contain a number of damaged caves that require immediate attention. Preserving our cultural heritage demands documentation, mapping, and modeling. The utilization of 3D visualization is paramount in recording cultural heritage data. Moreover, it contributes to the conservation, rehabilitation, and maintenance of historical structures. In the current era of scientific and technological advancements, laser scanners have made rapid progress. The data generated by these scanners plays a critical role as a backup to safeguard cultural heritage objects in case of damage, destruction, or loss. The benefits of employing 3D visualization lie in its ability to create detailed and integrated models, resulting in a comprehensive database accessible to all stakeholders. This study utilized the Block Bundle Adjustment methodology to map the prehistoric cave Leang Lambatorang and create a 3D visualization using a laser scanner. The research findings include the 3D visualization of the data from Leang Lambatoran

THE ANALYSIS OF POTATO CHIPS PRODUCT DAMAGED RISK IN WIDURI JOINT VENTURE GROUP

ABSTRACT The purpose of this research is to identify the risks of potato chips product damaged, to measure and map the risk and formulating an effective risk mitigation strategy for Widuri joint venture group. This research uses qualitative approach. The method of risk management with Enterprise Risk Management (ERM). The location of the research is in Kijang City, Bintan, Kepulauan Riau. Data research obtained by interview, observation and documentation. The results showed that there are several factors that can cause the failure of the production process and the product itself which was an error in the selection of raw materials, passing the process of soaking potatoes, a mistake in the provision of lime paste, errors at uncontrolled fire, and neglect of human resources that have impact for entity. The impact of arising from risk was product destroyed, potatoes become scorched, and the potato chips would be easy to catch cold. The amount of risk experienced by Widuri joint venture group were reflected in the risk map formed on the measurement of risk based on probability and impact. Widuri joint venture group certainly have to develop a strategy for an effective risk mitigation were prioritized addressing the highest risk first to a lower risk so that the risk of product damaged can be minimized. KeyWords: ERM, Product Damaged, Joint Ventur

THE ANALYSIS OF POTATO CHIPS PRODUCT DAMAGED RISK IN WIDURI JOINT VENTURE GROUP

The purpose of this research is to identify the risks of potato chips product damaged, to measure and map the risk and formulating an effective risk mitigation strategy for Widuri joint venture group. This research uses qualitative approach. The method of risk management with Enterprise Risk Management (ERM). The location of the research is in Kijang City, Bintan, Kepulauan Riau. Data research obtained by interview, observation and documentation. The results showed that there are several factors that can cause the failure of the production process and the product itself which was an error in the selection of raw materials, passing the process of soaking potatoes, a mistake in the provision of lime paste, errors at uncontrolled fire, and neglect of human resources that have impact for entity. The impact of arising from risk was product destroyed, potatoes become scorched, and the potato chips would be easy to catch cold. The amount of risk experienced by Widuri joint venture group were reflected in the risk map formed on the measurement of risk based on probability and impact. Widuri joint venture group certainly have to develop a strategy for an effective risk mitigation were prioritized addressing the highest risk first to a lower risk so that the risk of product damaged can be minimized.Key Words: ERM, Product Damaged, Joint Ventur