Although hydraulic fracturing in Liquid-Rich Unconventional Reservoirs (LUR) have become a norm, the recovery factor continues to be low. Use of Enhanced Oil Recovery (EOR) techniques in LUR have recently become more popular to improve the recovery. The objective of this study is to numerically investigate the advantages and disadvantages of the application of CO2 huff-n-puff technique in the LUR formations having complex fracture networks. The study explores the fluid flow mechanisms for oil recovery in the naturally fractured reservoir. A calibrated 3D mechanical earth model with geomechanical and petrophysical property from the Eagle Ford was used for the study. Complex hydraulic fracture model was used to simulate the hydraulic fractures, proppant and fluid distribution around the wellbore. Numerical reservoir simulation on a Perpendicular Bi-section (PEBI) grid was used to capture the permeability, porosity and conductivity distribution due to the proppants in the hydraulic fractures. CO2 huff-n-puff technique using numerical reservoir simulation is used to determine the well performance and recovery factor arising from reservoir fluid viscosity reduction and gas expansion. Effect of fluid thermodynamics to recovery systems in the low permeability reservoir medium is fully captured in approach. Equation of state prepared for simulating the CO2 impact on the oil is prepared with correlating the collected down hole oil sample. Numerical reservoir simulation study coupled with the complex fracture simulation model presents the insights of new means to improve RF in LUR through the injection of CO2. Such EOR method would be critical to increase the long term economic benefits. The study demonstrates that the infill well requirements can be mitigated if the EOR method of Huff-n-puff is utilized in cyclic modes over various time periods of production. Up to 9% extra RF was observed when CO2 Huff-n-puff technique was used as compared to production dependent only on hydraulic fracture stimulation. Parametric sensitivity on job sizes and start timing of EOR in a producing well is used to evaluate the RF. However, the hydraulic fracture geometry and the created footprint along with the time of injection has a larger effect in improving the EOR effectiveness. The methodology provides the demonstration of simulating the EOR methods in unconventional reservoirs for economic assessment. The workflow demonstrates modeling CO2 flooding as an EOR technique on the full wellbore level with complex hydraulic fracture geometry. The approach demonstrated here can be applied to other basins in the unconventional formations to improve the recovery factor.
The use of relatively small-scale distributed electric power generation sources is one of the key focus areas in the development of global industry and regional power generation. By integrating distributed generation sources into their on-site energy infrastructure, industrial consumers gain new characteristics and possibilities as entities of the power system that do not only consume power, but in fact can flexibly generate and deliver electricity to local and even centralized grids. This type of entity is called a distributed energy resource system with demand response (Russian: ‘active energy complex’). The purpose of this study is to lay the methodological foundation for the use of distributed energy resource systems with demand response in industrial sites under existing gas and power market conditions and for ensuring the synchronization of parameters that is necessary for managing complex energy consumption. This article provides an empirical study of the principles of the natural gas pricing under the demand volatility of regional markets and the Russian Mercantile Exchange. The article outlines the key drivers, as identified by the authors, that impact gas consumption by a distributed energy resource system, including demand characteristics, limitations and capacity of the gas network and the mode of gas consumption by an industrial enterprise and its generator. Accounting for all of these factors is essential for effective management and proper operational adjustment of a distributed energy resource system with demand response. The result of the study is a proprietary model and a tool for the management of distributed energy resource systems in integration with the gas demand management, which analyze the internal and external parameters of the industrial entity’s operations and its distributed energy resource system, as well as factors existing in the integrated distributed energy system where the consumer is able to buy natural gas in various market segments. The proprietary tool of distributed energy resource system management is based on the centralized control system, which combines performance analytics, operational scheduling of production and the distributed energy resource system, price planning for the wholesale and retail power markets, regional gas markets and exchange, monitoring all elements of the system, and assessment of different active energy management scenarios under various external and internal conditions impacting production and energy demand. Our proprietary tool has been successfully tested in a typical industrial site and was reported to deliver a significant electricity and gas cost-saving effect, which amounted to an 18 percent reduction in the total energy costs of the company, or more than USD 2.6 million per year. The resulting saving effect can recoup the costs of investing in a distributed energy resource system, including construction and installation of the local grid and automation infrastructure, and can be obtained in any country of the world.
31 December 2018 in International Journal of Energy Production and Management
В статье описывается разработанная авторами модель диагностики готовности компании к реализации инновационных проектов высокого риска. Модель была протестирована на крупном предприятии пищевой промышленности города Челябинска. В рамках апробации были выявлены значимые различия в восприятии компании и стратегии ее развития разными функциональными группами реальных и потенциальных сотрудников, что затрудняет эффективную реализацию инноваций на предприятии. Опираясь на результаты анализа, авторами составлена матрица «проблемных зон» и предложены рекомендации по их устранению. Только реализации коррекционных мероприятий позволит предприятию достичь состояния, при котором оно будет способно обеспечить высокорисковые проекты эффективной командой с минимальным риском.