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Simulation of Heavy Oil Production using Smart Wells
Get PDFThe application of long horizontal wells, especially in heavy oil reservoirs with a water drive, is associated with some challenges including the early breakthrough of water into the well. To solve this challenge, smart horizontal wells completed with downhole flow control devices (FCDs) and zonal isolation are widely used today. Therefore, evaluating the functionality of different types of FCDs in reducing water cut is necessary to achieve a successful design of smart wells for heavy oil production. In this paper, heavy oil production from smart wells completed with the main types of FCDs is modeled and simulated through a case study. According to the obtained results, compared to conventional wells, by using smart wells more oil and at the same time, less water can be produced from heavy oil reservoirs. Besides, in comparison with ICDs, AICDs and AICVs have better functionality in improving oil recovery and reducing water cut. It can also be concluded that among the main types of FCDs, AICVs have the best performance in achieving cost-effective heavy oil production
Simulation-based Cost Optimization tool for CO2 Absorption Processes: Iterative Detailed Factor (IDF) Scheme
Get PDFA simple, fast, and accurate process simulation based cost estimation and optimization scheme was developed in Aspen HYSYS based on a detailed factorial methodology for solvent-based CO2 absorption and desorption processes. This was implemented with the aid of the spreadsheet function in the software. The aim is to drastically reduce the time to obtain cost estimates in subsequent iterations of simulation due to parametric changes, studying new solvents/blends and process modifications. All equipment costs in a reference case are obtained from Aspen In-Plant Cost Estimator V12. The equipment cost for subsequent iterations are evaluated based on cost exponents. Equipment that are not affected by any change in the process are assigned a cost exponent of 1.0 and the others 0.65, except the absorber packing height which is 1.1. The capital cost obtained for new calculations with the Iterative Detailed Factor (IDF) model are in good agreement with all the reference cases. The IDF tool was able to accurately estimate the cost optimum minimum approach temperature based on CO2 capture cost, with an error of less than 0.2%
Fluidization of Fine Calciner Raw Meal Particles by mixing with coarser Inert Particles – Experiments and CPFD Simulations
Get PDFThe calciner has a significant role in the production of cement. It is the most energy-intensive process unit in the production process. Most modern calciners are entrainment-based, i.e., a hot gas pneumatically conveys the particles through the calciner. A fluidized bed is an alternative to the entrainment calciner, which may be of special interest if the calcination process is to be electrified, so that the raw meal is mainly calcined by heat transfer from a hot surface and not by direct contact with hot combustion gases. The fine particle size of the raw meal, however, makes it a challenge to fluidize. This study looks into an alternative solution in which the cement raw meal is mixed with coarse sand particles to enhance the fluidization behavior. Experiments are first conducted to fluidize pure cement raw meal (fine particles) and sand (coarse particles) separately. Then they are mixed at fine/coarse mass ratios of 25%/75% and 50%/50%. Simulations are then performed, using a commercial CPFD software (Barracuda ®, version 20.0.0), to replicate the results from the experiments. The experimental results indicate that it is technically feasible to fluidize cement raw meal by mixing it with coarse inert particles at the mentioned fine/coarse mass ratios. Stable fluidization was observed at a superficial gas velocity of 0.3 m/s. The pressure drop results from simulations and experiments matched quite well at both mixing ratios. Hence, the CPFD simulations may be used as an aid in the design of a potential full-scale calciner applying this concept
Design of a Medium-scale Circulating Fluidized Bed Reactor for Chlorination of processed Aluminum Oxide
Get PDFFluidization is a well-established and widely used technology in the process industry. The production stability and the large effective contact area between the active substances, resulting in high mass and heat transfer between the phases, are some of the main advantages of fluidization. However, this technology has not yet been adequately developed for alumina chlorination as a standard solution on an industrial scale. Although a circulating fluidized bed reactor design is complex by its nature, it is advantageous to simulate the process compared to running experiments on a lab scale. The Computational Particle-Fluid Dynamic (CPFD) simulation lays a foundation for studying the given reaction process. The reaction between the solid alumina particles and the gaseous chlorine and carbon monoxide results in the products (aluminum chloride and carbon dioxide). The present study aims to design a circulating fluidized bed reactor by simulating the process in Barracuda®. Simulations with a simple geometry contributed to a better understanding of the reaction process. Then the simulation results are compared with values from both a theoretical approach and parallel simulations in Aspen Plus®. The comparison revealed that the results from Barracuda® Virtual Reactor (VR), such as product flow rate, are within a reasonable range of what could be expected in a full-scale plant. The promising preliminary results imply that CPFD could be a promising approach for future research on the design, optimization, and implementation of the industrial alumina chlorination process. The final design includes a fluidized bed reactor with a 2.4 m internal diameter and 8 m height and four parallel internal cyclones on top
Study of the Thermal Performance of an Industrial Alumina Chlorination Reactor based on CPFD Simulation
Get PDFAs a part of the new sustainable aluminum production process under study, alumina chlorination plays a crucial role. The relevant process is an exothermic reaction in a fluidized bed reactor. The solid alumina reacts with chlorine and carbon monoxide and produces aluminum chloride and carbon dioxide as the main products. Then carbon dioxide can be separated efficiently. The optimum temperature for the alumina chlorination is 700℃. The reactor’s temperature should be kept in the range of 650-850℃ (most preferably 700℃) because below that temperature range, the reaction rate drops, and above that range, the alumina (which usually is γ-alumina) transfers to other alumina types, which is not desirable for the purpose. Extending other simulation studies by authors on alumina chlorination in an isothermal condition, the CPFD method has been utilized to thermal study and simulate the overall heat transfer of the system, including convective fluid to the wall, fluid to particle, and radiation heat transfer. Radial and axial heat transfer coefficient profiles at different levels show that almost all the heat should be transferred in the lower half of the reactor, making the design more challenging. At the steady-state, the range for the fluid temperature inside the reactor has been recorded 700-780℃
The Application of the Lattice Boltzmann Method in the Calculation of the Virtual Mass
Get PDFVirtual mass is an important quantity in the analysis of the unsteady motion of objects underwater or other fluids or unsteady flow around bodies, for example, the virtual mass effect is important in the inertia of ships, floaters, swimmers’ organs, airplanes, and bubbles. The additional mass resulting from the fluid acting on the structure can be calculated by solving the equation of potential flow around the object. In this paper, a system in which a square object is immersed in a channel of fluid and moves parallel to the wall has been considered. The corresponding virtual mass at a determined distance S from the wall and for the object size D (the side of the square object) is calculated via the Lattice Boltzmann Method. Here, it is tried to change D and S separately and investigate their effects on the virtual mass. According to the simulation results, for the systems in which the distance from the wall is more than four times the object size (S > 4D), the distance does not influence the added mass. Furthermore, the virtual mass rises when the object approaches the wall and experiences its maximum value as it reaches the wall (S → 0). As a result, in this case, the virtual mass is about 75% larger than in the case of S=4D. In addition, the simulations reveal that by increasing the dimensions of the object D the virtual mass increases and vice versa
Possible Concepts for Digital Twin Simulator for WWTP
Get PDFApplication of advanced modeling and simulation technologies is essential to meet future requirements for higher wastewater treatment capacity and increased discharge water quality without large investments in construction projects. This article describes an industrial pre-project for digital twin simulator for Veas wastewater treatment plant in Norway. The desired main functionalities of the digital twin simulator were:• Data- and model-based management as well as decision support for process operators• Predictive operational support and process optimization for engineers• Testing of process modifications, control system modifications, new procedures and other changes• Competency building and knowledge transfer between the operators and engineersCommercially available technologies were compared according to the functional design specification and four possible digital twin simulator concepts were developed for wastewater treatment facilities
A Comparative Model-Analysis on Sulphide Bio-oxidation with Different Electron Acceptors
Get PDFSulphide (H2S, HS- and S2-) is an undesired by-product of biogas production processes. This modelling work in Aquasim was carried out to study three parallel processes related to sulphide in AD processes: 1) H2S liquid-gas mass transfer; 2) Acid-base equilibrium; and 3) Sulphide oxidation with three different electron acceptors; nitrate, oxygen, and a biotic anode with a given potential. Multiplicative Monod (biotic processes) and Nernst-Monod kinetics (bioelectrochemical process) provide the basis for the sulphide bio-oxidation processes. At the current stage, the model can be used to study sulphide bio-oxidation and the effect of relevant parameters, including initial biomass concentration, uptake rates, temperature, and pH. The model can be improved further by implementing anaerobic microbial processes as competing reactions. With the proposed improvements, the model can be a useful tool for calculating the chemical dosage or electrode potential required for sulphide removal. These calculations can be based on both the concentration of H2S(g) in the headspace (ppm) often available at full-scale plants and the concentration of sulphide (HS-(liq)) in effluent streams from the plants
Himalayan Run-Off River Power Generation Modelling for Power Security in Evolving Weather Conditions
Get PDFExtreme black-swan occurrences like earthquakes, glacial lake outbursts, flash floods, landslides, etc. are important concerns in Himalayan countries like Nepal, which are highly susceptible, geologically active, and exquisitely fragile. Nepal generates 97 percent of its electricity from hydropower, where 56.08 percent of it is coming from seasonal run-off-river (RoR) hydro plants. Landslides and mudflows are common in the monsoon, and low discharge is common in the winter season. These RoR plants must be able to withstand high-impact events like earthquakes and lengthy droughts in order for the Nepalese grid to remain secure. This study gives a presentation and overview of previously occured natural hazards in Nepal related to hydropower plants. In particular, the 2014 Sunkoshi landslide and the 2021 Melamchi flood are evaluated as extreme events and their impacts on hydropower plant has been studied. In addition, an in-depth investigation on a ROR plant is carried out. Moreover, the water discharge and extreme rainfall peaks in time series data is evaluated using an ARIMA-based model. This paper shows the feasibility of predicting the energy produced by a run-off river hydropower plant. The purpose is to forecast discharge and hence the ROR power generation with the aim to facilitate the hydropower operators for their availability declaration which will again help in the overall energy planning. The results are discussed together with performance metrics, and indicates that the implemented technique is promising.These predictions can be further used for planning and estimating the power generation on a more complex level
Evaluation of Complex Spray Behaviors of Sprinkler Spray Using FDS
Get PDFIt takes money, time, and energy to set up an experimental grid to measure the effectiveness of fire suppression parameters. Therefore, computational fluid dynamics (CFD) is an alternative in all fields as consequences modeling. Fire Dynamic Simulator (FDS) is a CFD software developed by the National Institute of Standards in Technology (NIST) to model and generate the results for the spray models. FDS uses Large Eddy Simulation (LES) to represent turbulence. The current study utilizes FDS to investigate the extinguishing efficiency of sprinkler spray on e general fire. The study focuses on analyzing the effectiveness of suppression parameters using complex (polydisperse) in contrast to the simplified (monodisperse) representation of the spray with- and without a fire scenario of a 2560 kW propane fire. Measurements were taken by digitally enabled Phase Doppler Particle Analyzer (PDPA) to measure the fire suppression parameters such as number concentration, droplet size distribution (DSD) & velocity distribution. The measurements were taken 1.5 m downstream of the sprinkler. The suppression parameters are compared with monodisperse and polydisperse with and without fire. Thus, the suppression parameters have been compared to measure the effect