Dimethyl Ether as a Novel Solvent for Bitumen Recovery: Mechanisms of Improved Mass Transfer and Energy Efficiency

SPE Journal ◽  
2021 ◽  
pp. 1-20
Author(s):  
Min Yang ◽  
Maojie Chai ◽  
Rundong Qi ◽  
Zhangxin Chen ◽  
Linyang Zhang ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Energy Efficiency ◽  
Energy Consumption ◽  
Dimethyl Ether ◽  
Oil Production ◽  
Recovery Process ◽  
Thermal Recovery ◽  
Production Performance ◽  
Reservoir Rock ◽  
Bitumen Recovery

Summary A solvent-based thermal recovery process has the advantages of low capital expenditure, less energy consumption, and less greenhouse gas emission. Dimethyl ether (DME), as a renewable solvent, has been considered as a novel additive in the thermal bitumen recovery process. Being soluble in both water and oil phases, DME has the potential to enhance mass transfer and improve oil production. In this work, a phase behavior model of the DME-bitumen-water system is first developed considering DME partitioning between oil and water. A field-scale numerical simulation model with fine gridblocks is developed to investigate the heat and mass transfer mechanisms between DME and bitumen in the interface of a DME vapor chamber. The numerical model is validated with physical experiment results. The close agreement between measured and simulated production profiles indicates that the mechanisms are adequately captured. Meanwhile, various simulation scenarios are performed to evaluate the production performance and the energy efficiency, which is defined as the energy/oil ratio. It is found that the oil production rate in DME injection is 15% higher than that in butane injection at the early stage of production. The solvent penetration depth in DME injection is larger than that in butane injection. This is attributed to the enhanced mass transfer between DME and bitumen caused by the high diffusion of DME in the water phase and preferential partitioning of DME into the oil phase. Furthermore, energy consumption in the warm DME injection process is 48% less than that in warm butane injection and 75% less than that in steam-assisted gravity drainage (SAGD). This is because DME injection can be operated at a lower-temperature condition, leading to less energy transferred to heat reservoir rock/fluids and less heat loss to over/underburden. Therefore, DME is proved to be a technically promising and environmentally friendly solvent to enhance bitumen recovery. The DME-based thermal recovery technique exhibits superior advantages in unlocking poor-quality reservoirs, especially in high water saturation reservoirs and thin reservoirs.

scholarly journals Increase of the energy efficiency in paper industry

2008 ◽  
Vol 62 (4) ◽  
pp. 233-245
Author(s):  
Milorad Krgovic ◽  
Vladimir Valent ◽  
Marina Krsikapa ◽  
Miodrag Milojevic ◽  
Branko Raseta ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Energy Efficiency ◽  
Energy Consumption ◽  
Specific Heat ◽  
Paper Industry ◽  
Electric Energy ◽  
Paper Drying ◽  
Improve Energy Efficiency ◽  
Electric Energy Consumption ◽  
Paper Machines

In this work, phenomena of heat and mass transfer in process of paper drying are given, certain technology units are analyzed, while possibility for decrease of specific heat and electric energy consumption by modernization of technology is examined. Some of the solutions applied on paper machines worldwide in order to improve energy efficiency are shown. Theoretic and practical discoveries in this area are applied in Board factory UMKA, and these results are shown in the work as well.

Influence of Pressure Difference Between Reservoir and Production Well on Steam-Chamber Propagation and Reservoir-Production Performance

SPE Journal ◽  
2019 ◽  
Vol 24 (02) ◽  
pp. 452-476 ◽  
Author(s):  
Hao Xiong ◽  
Shijun Huang ◽  
Deepak Devegowda ◽  
Hao Liu ◽  
Hao Li ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Production Rate ◽  
Pressure Difference ◽  
Oil Production ◽  
Thermal Recovery ◽  
Production Performance ◽  
Production Model ◽  
Steam Chamber ◽  
Proposed Model ◽  
Expansion Angle

Summary Steam-assisted gravity drainage (SAGD) is the most-effective thermal recovery method to exploit oil sand. The driving force of gravity is generally acknowledged as the most-significant driving mechanism in the SAGD process. However, an increasing number of field cases have shown that pressure difference might play an important role in the process. The objective of this paper is to simulate the effects of injector/producer-pressure difference on steam-chamber evolution and SAGD production performance. A series of 2D numerical simulations was conducted using the MacKay River and Dover reservoirs in western Canada to investigate the influence of pressure difference on SAGD recovery. Meanwhile, the effects of pressure difference on oil-production rate, stable production time, and steam-chamber development were studied in detail. Moreover, by combining Darcy's law and heat conduction along with a mass balance in the reservoir, a modified mathematical model considering the effects of pressure difference is established to predict the SAGD production performance. Finally, the proposed model is validated by comparing calculated cumulative oil production and oil-production rate with the results from numerical and experimental simulations. The results indicate that the oil production first increases rapidly and then slows down when a certain pressure difference is reached. The pressure difference has strong effects on steam-chamber-rising/expansion stages. However, at the expansion stage, lower pressure difference can achieve the same effect as high pressure difference. In addition, it is shown that the steam-chamber-expansion angle is a function of pressure difference. Using this finding, a new mathematical model is established considering the modification of the expansion angle, which (Butler 1991) treated as a constant. With the proposed model, production performance such as cumulative oil production and oil-production rate can be predicted. The steam-chamber shape is redefined at the rising stage, changing from a fan-like shape to a hexagonal shape, but not the single fan-like shape defined by (Butler 1991). This shape redefinition can clearly explain why the greatest oil-production rate does not occur when the steam chamber reaches the caprock. Literature surveys show few studies on how pressure difference influences steam-chamber development and SAGD recovery. The current paper provides a modified SAGD production model and an entirely new scope for SAGD enhanced oil recovery (EOR) that makes the pressure difference a new optimizable factor in the field.

A New Method for Measuring Solvent Diffusivity in Heavy Oil by Dynamic Pendant Drop Shape Analysis (DPDSA)

SPE Journal ◽  
2006 ◽  
Vol 11 (01) ◽  
pp. 48-57 ◽  
Author(s):  
Chaodong Yang ◽  
Yongan Gu
Keyword(s):  
Carbon Dioxide ◽  
Mass Transfer ◽  
High Pressure ◽  
Objective Function ◽  
Heavy Oil ◽  
Oil Production ◽  
Thermal Recovery ◽  
Oil Reservoirs ◽  
Pressure Cell ◽  
Heavy Oil Reservoirs

Summary This paper presents a new experimental method and its computational scheme for measuring solvent diffusivity in heavy oil under practical reservoir conditions by DPDSA. In the experiment, a see-through windowed high-pressure cell is filled with a test solvent at desired pressure and temperature. Then, a heavy-oil sample is introduced through a syringe delivery system to form a pendant oil drop inside the pressure cell. The subsequent diffusion of the solvent into the pendant oil drop causes its shape and volume to change until an equilibrium state is reached. The sequential digital images of the dynamic pendant oil drop are acquired and digitized by applying computer-aided digital image-acquisition and -processing techniques. Physically, variations of the shape and volume of the dynamic pendant oil drop are attributed to the interfacial tension reduction and the well-known oil-swelling effect as the solvent gradually dissolves into heavy oil. Theoretically, the interfacial profile of the dynamic pendant oil drop is governed by the Laplace equation of capillarity, and the molecular diffusion process of the solvent into the pendant oil drop is described by the diffusion equation. An objective function is constructed to express the discrepancy between the numerically predicted and experimentally observed interfacial profiles of the dynamic pendant oil drop. The solvent diffusivity in heavy oil and the mass-transfer Biot number are used as adjustable parameters and thus are determined once the minimum objective function is achieved. This novel experimental technique is tested to measure diffusivities of carbon dioxide in a brine sample and a heavy-oil sample, respectively. It should be noted that, with the present technique, a single diffusivity measurement can be completed within an hour and only a small amount of oil sample is required. The interface mass-transfer coefficient at the solvent/heavy-oil interface can also be determined. In particular, this new technique allows the measurement of solvent diffusivity in an oil sample at constant prespecified high pressure and temperature. Therefore, it is especially suitable for studying the mass-transfer process of injected solvent into heavy oil during solvent-based post-cold heavy-oil production (post-CHOP). Introduction Western Canada has tremendous heavy oil and bitumen resources (Farouq Ali 2003, Miller et al. 2002). Approximately 80 to 95% of the original-oil-in-place is still left behind at the economic limit after cold heavy-oil production (Miller et al. 2002). This is a large oil-in-place target for follow-up enhanced oil recovery (EOR) processes. After primary production, most Canadian heavy-oil reservoirs cannot be further exploited economically by thermal recovery processes because reservoir formations are thin and/or there is active bottomwater. In the literature, some studies have been conducted to evaluate the other recovery methods for these heavy-oil reservoirs (Miller et al. 2002, Das 1995, Frauenfeld et al. 1998, Metwally 1998). Among these methods, vapor extraction (VAPEX) and other solvent-based post-CHOP processes are probably the most promising EOR techniques. In practice, the solvent can be carbon dioxide, flue gas, and light hydrocarbon gases, such as methane, ethane, propane, and butane.

scholarly journals Methods of calculation of energy losses of the refrigerator when opening its doors

2018 ◽  
Vol 215 ◽  
pp. 01018
Author(s):  
S.P. Petrosov ◽  
M.A. Lemeshko ◽  
A.V. Kozhemyachenko ◽  
S.E. Bashnjak
Keyword(s):  
Mass Transfer ◽  
Energy Efficiency ◽  
Energy Consumption ◽  
Global Economy ◽  
Air Flow ◽  
Experimental Studies ◽  
Ambient Air ◽  
Modern World ◽  
Functional Dependencies ◽  
Navier Stokes Equation

The problem of energy supply and the problem of energy efficiency of energy consumers are global problems. In the modern world, scientists pay much attention to the tasks of creating new and improving traditional sources of electricity. The tasks of increasing the energy efficiency of electricity consumers remain relevant in the global economy. One of the relatively capacious energy consumers is the Park of refrigerators, household and commercial purposes, which are also being improved in order to increase their energy efficiency. Modernization and improvement of household and commercial refrigerators include the task of designing and using more efficient refrigerators. Energy consumption of compression refrigerators, along with other operational factors, depends on the processes of heat exchange and mass transfer of air from internal chambers to the ambient air. When the doors of the refrigerator chambers are opened, the cooled air in the chambers is replaced with the warmer air of the environment. This process causes the cost of operation of the refrigeration machine and characterizes its energy consumption. In order to minimize this power consumption, knowledge of the process of cool air outflow of their open refrigerator chambers is required. Currently, this process is poorly understood. The article presents an approach to the description of the process of motion of the cooled air from the refrigerator chamber, the main assumptions necessary for the construction of a mathematical model of this process are given, and a method for calculating the heat in the refrigerator chambers associated with the replacement of the cooled air with the ambient air inside the chambers is proposed. The method is based on the laws of gas dynamics, supplemented by some experimental studies. In particular, the well — known Navier-Stokes equation is used as the initial basis. This equation supplemented by the continuity equation of the air flow and other functional dependencies. As a result of mathematical transformations and arguments about the physics of the mass transfer process, finite equations are obtained, which allow describing both the performance of the cooled air flow and the amount of heat introduced into the chambers by external warm air. Mathematical dependences are developed for calculation of parameters of motion of a stream of the cooled air and heat inflows, thus the temperature of ambient air and temperature in chambers of the refrigerator are considered. The results of the research will be useful in the design of new refrigerating machines with reduced energy consumption.

A Methodological Analysis of the Mechanisms Associated With Steam/Solvent Coinjection Processes Using Dynamic Gridding

SPE Journal ◽  
2016 ◽  
Vol 21 (06) ◽  
pp. 2238-2249 ◽  
Author(s):  
A.. Perez-Perez ◽  
M.. Mujica ◽  
I.. Bogdanov ◽  
J.. Hy-Billiot
Keyword(s):  
Mass Transfer ◽  
Oil Recovery ◽  
Oil Production ◽  
Thermal Recovery ◽  
Gravity Drainage ◽  
Published Data ◽  
Good Precision ◽  
Edge Zone ◽  
Steam Chamber ◽  
Phase Mobility

Summary Hybrid steam-solvent processes have gained importance as a thermal-recovery process for heavy oils in recent years. Numerous pilot projects during the last decade indicate the increasing interest in this technology. The steam/solvent coinjection process aims to accelerate oil production, increase ultimate oil recovery, reduce energy and water-disposal requirements, and diminish the volume of emitted greenhouse gases compared with the steam-assisted-gravity-drainage (SAGD) process. Among the identified physical mechanisms that play a role during the hybrid steam/solvent processes are the heat-transfer phenomena, the gravity drainage and viscous flow, the solvent mass transfer, and the mass diffusion/dispersion phenomena. The major consequence of this complex interplay is the improvement of oil-phase mobility that is controlled by the reduction in the oil-phase viscosity at the edge of the steam chamber. It follows that a detailed representation of this narrow zone is necessary to capture the involved physical phenomena. In this work, a study of sensitivity to grid size was carried out to define the appropriate grid necessary to represent the near-edge zone of the steam/solvent chamber. Our results for the steam/solvent coinjection process in a homogeneous synthetic reservoir indicate that a decimetric scale is required to represent with a good precision the heat and mass-transfer processes taking place at the edge of the steam chamber. In addition, we present some numerical results of the adaptive dynamic gridding application. Comparison was performed between the SAGD process and steam/solvent coinjection after the characterization and analysis of the mechanisms that govern oil production under typical Athabasca oil-sand conditions. Finally, in the framework of the proposed numerical methodology, the effect of solvent type and injection conditions on the oil-recovery efficiency is quantitatively illustrated. Published data for similar applications are also discussed. It is expected that this work will provide some insight for the simulation community about methodological aspects to be taken into account when hybrid steam/solvent processes would be modeled.

Numerical Evaluation of the Impact of Steam Quality on Steam Flood Performance in a Kuwait Heavy Oil Reservoir

2021 ◽  
Author(s):  
Yacob Al-Ali ◽  
Abdullah Al-Rubah ◽  
Marco Verlaan
Keyword(s):  
Energy Efficiency ◽  
Heat Loss ◽  
Oil Recovery ◽  
Energy Content ◽  
Recovery Process ◽  
Thermal Recovery ◽  
Steam Quality ◽  
Bottom Hole ◽  
Steam Flood ◽  
The Impact

Abstract The objective of this study is to assess any opportunities to improve field recovery or thermal efficiency by evaluating different steam quality scenarios and their impact on the performance of the cyclic steam stimulation and steam flood in Lower Fars reservoir. In this study, simulation history matching of the dynamic test data from the ongoing thermal pilots was used to validate the static and dynamic description. The process results in an improved dynamic model to be used specifically for the steam quality scenarios evaluation, which was then used in the prediction mode for deciding on an optimum steam quality percentage for the upcoming steam flood operation. Different bottom-hole steam quality scenarios are defined using different steam quality output values at the steam generator and a fixed amount of surface network heat loss. The wellbore heat losses are explicitly modelled to arrive at bottom hole steam quality corresponding to a boiler steam quality. The impact of the steam quality on the cumulative amount of oil produced is significant when an economic steam oil ratio cutoff is applied. There was an overall 40% difference in cumulative oil production between low and high steam quality cases, and a 30% difference when an energy cut off criterion was applied instead of the steam oil ratio cutoff. The highest steam quality resulted in the best performance in terms of oil recovery and energy efficiency. Analysis of the results show that the effect of steam quality is different during different periods of the CSS/SF process and mainly related to the different amount of enthalpy injected. During the CSS period a lower steam quality results in lower oil recovery but at a better efficiency compared to a high steam quality. In the steam flood phase the high steam quality results in both higher recovery and higher energy efficiency. The latter is caused by lower over and underburden heat loss. The bottom hole steam quality is a measure of the energy content of the steam that is delivered to the reservoir. This has a significant impact on the efficiency of the thermal recovery process. The steam quality can vary as function of well location and time for numerous reasons. Thus, it is essential to understand how these variables affect the recovery process.

Improving Energy Efficiency in Internet of Things using Artificial Bee Colony Algorithm

2020 ◽  
Vol 14 ◽  
Author(s):  
M. Sivaram ◽  
V. Porkodi ◽  
Amin Salih Mohammed ◽  
S. Anbu Karuppusamy
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Artificial Bee Colony ◽  
Trust Model ◽  
Sensor Nodes ◽  
Remote Areas ◽  
Bee Colony ◽  
Important Concern ◽  
Wide Range ◽  
Iot Devices

Background: With the advent of IoT, the deployment of batteries with a limited lifetime in remote areas is a major concern. In certain conditions, the network lifetime gets restricted due to limited battery constraints. Subsequently, the collaborative approaches for key facilities help to reduce the constraint demands of the current security protocols. Aim: This work covers and combines a wide range of concepts linked by IoT based on security and energy efficiency. Specifically, this study examines the WSN energy efficiency problem in IoT and security for the management of threats in IoT through collaborative approaches and finally outlines the future. The concept of energy-efficient key protocols which clearly cover heterogeneous IoT communications among peers with different resources has been developed. Because of the low capacity of sensor nodes, energy efficiency in WSNs has been an important concern. Methods: Hence, in this paper, we present an algorithm for Artificial Bee Colony (ABC) which reviews security and energy consumption to discuss their constraints in the IoT scenarios. Results: The results of a detailed experimental assessment are analyzed in terms of communication cost, energy consumption and security, which prove the relevance of a proposed ABC approach and a key establishment. Conclusion: The validation of DTLS-ABC consists of designing an inter-node cooperation trust model for the creation of a trusted community of elements that are mutually supportive. Initial attempts to design the key methods for management are appropriate individual IoT devices. This gives the system designers, an option that considers the question of scalability.

The Research of Measuring Approach and Energy Efficiency for Hadoop Periodic Jobs

2015 ◽  
Vol 8 (1) ◽  
pp. 206-210 ◽  
Author(s):  
Yu Junyang ◽  
Hu Zhigang ◽  
Han Yuanyuan
Keyword(s):  
Energy Efficiency ◽  
Cloud Computing ◽  
Energy Consumption ◽  
Energy Saving ◽  
Energy Estimate ◽  
Cloud Platform ◽  
Periodic Tasks ◽  
Current Consumption ◽  
Reduce Energy Consumption

Current consumption of cloud computing has attracted more and more attention of scholars. The research on Hadoop as a cloud platform and its energy consumption has also received considerable attention from scholars. This paper presents a method to measure the energy consumption of jobs that run on Hadoop, and this method is used to measure the effectiveness of the implementation of periodic tasks on the platform of Hadoop. Combining with the current mainstream of energy estimate formula to conduct further analysis, this paper has reached a conclusion as how to reduce energy consumption of Hadoop by adjusting the split size or using appropriate size of workers (servers). Finally, experiments show the effectiveness of these methods as being energy-saving strategies and verify the feasibility of the methods for the measurement of periodic tasks at the same time.

Pre- and post-operam comparison of the energy consumption of a radio base station under energy efficiency actions

2021 ◽  
Vol 236 ◽  
pp. 110772
Author(s):  
Carmela Vetromile ◽  
Antonio Spagnuolo ◽  
Antonio Petraglia ◽  
Antonio Masiello ◽  
Maria Rosa di Cicco ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Base Station

scholarly journals Power and Performance Evaluation of Memory-Intensive Applications

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4089
Author(s):  
Kaiqiang Zhang ◽  
Dongyang Ou ◽  
Congfeng Jiang ◽  
Yeliang Qiu ◽  
Longchuan Yan
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Power Consumption ◽  
Job Scheduling ◽  
Memory System ◽  
Processor Core ◽  
Memory Efficiency ◽  
And Performance ◽  
Reasonable Use ◽  
Server System

In terms of power and energy consumption, DRAMs play a key role in a modern server system as well as processors. Although power-aware scheduling is based on the proportion of energy between DRAM and other components, when running memory-intensive applications, the energy consumption of the whole server system will be significantly affected by the non-energy proportion of DRAM. Furthermore, modern servers usually use NUMA architecture to replace the original SMP architecture to increase its memory bandwidth. It is of great significance to study the energy efficiency of these two different memory architectures. Therefore, in order to explore the power consumption characteristics of servers under memory-intensive workload, this paper evaluates the power consumption and performance of memory-intensive applications in different generations of real rack servers. Through analysis, we find that: (1) Workload intensity and concurrent execution threads affects server power consumption, but a fully utilized memory system may not necessarily bring good energy efficiency indicators. (2) Even if the memory system is not fully utilized, the memory capacity of each processor core has a significant impact on application performance and server power consumption. (3) When running memory-intensive applications, memory utilization is not always a good indicator of server power consumption. (4) The reasonable use of the NUMA architecture will improve the memory energy efficiency significantly. The experimental results show that reasonable use of NUMA architecture can improve memory efficiency by 16% compared with SMP architecture, while unreasonable use of NUMA architecture reduces memory efficiency by 13%. The findings we present in this paper provide useful insights and guidance for system designers and data center operators to help them in energy-efficiency-aware job scheduling and energy conservation.

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