The separation of produced fluids is essential once it reaches the surface. This separation is achieved in gravity separators. The design and sizing of separators can be challenging due to the number of factors involved. Improper separator design can bottleneck and reduce the production of the entire facility. This paper describes the development of a capital cost optimisation model for sizing three phase separators. The developed model uses GRG Non-linear algorithms to determine the minimum cost associated with the construction of horizontal separators subject to four sets of constraints. A numerical sizing example was solved to provide the details associated with the model and the ease with which parameters can be varied to suit the user's needs. Finally, a spreadsheet comparison between results obtained from the developed model and four other extant models is carried out. Results indicated that the developed model predicted results within an absolute error of AE5m 3 in most cases and a maximum of AE12.5m 3 for very high gas flows in comparison to conventional models developed based on retention time theory.
Cost–benefit analysis is a common evaluation method applied to assess whether an energy system is economically feasible as well as the economic viability of energy investment for the energy transition of a pre-existing energy system. This paper focuses on examining the economic costs and benefits obtained through the implementation of renewable energy and smart technology to a pre-existing energy system of two pilot sites—St. Jean and Barcelona. The evaluation process includes all relevant parameters such as investment, operating and maintenance costs, and energy prices needed to assess the economic feasibility of the investment. The results show that investing in energy system development towards a decarbonized future, can provide various benefits such as increased flexibility, and reduced emissions while being economically feasible.
Summary
In this work, the performance of two pilot–scale separators was investigated using computational–fluid–dynamics (CFD) simulation with one operating at low gas volumetric quality comprising a bucket–and–weir configuration, and the other operated at high gas volumetric quality with a weir configuration. The pilot–scale separators were selected for this work because of their availability and the lack of data on industrial separators. The effects of the liquid (oil and water) flow rate and weir height on separation performance have been investigated for the separator operating at low gas volumetric quality. For this separator, the design of experiments (DOE) and a preliminary run of the separator were used to select the number of experiments and simulations to conduct and the levels (values) of the three variables investigated. For the second separator, the effects of the inlet flow rate on separation performance have been investigated.
Eulerian and volume–of–fluid (VOF) multiphase–flow models in ANSYS® Fluent (Fluent 2019), combined with a k–ε turbulence model, were used to simulate the fluid–flow pattern and phase behavior inside each of the separators. The numerical solutions were initialized with a water level set at 50% of the weir height using a patching tool. A mesh–independence test was carried out to ensure that the results are not dependent on the mesh quality.
The separation efficiencies from both models were compared with that from the experimental data. The results indicated that the two multiphase models, namely, Eulerian and VOF, predict the experimental results within 30% error. However, different separation performances were obtained for the same flow conditions. For the separator operating at low gas volumetric quality, the results from the Eulerian multiphase model produced a maximum deviation of 8%, while results from the VOF multiphase model produced a maximum deviation of 23% of the experimental data. For this separator, the oil flow rate was found to have the greatest effect on the separation efficiency. This is followed by the water flow rate and weir height.
For the separator operating at high gas volumetric quality, a maximum percentage error of 30% for the Eulerian model and 21% for the VOF was obtained.
This paper presents a comparative study of two commonly used three-phase separator design procedures; Arnold and Stewart and Svrcek and Monnery. The procedures were developed based on droplet settling and retention time theories for the separation of gas, oil and water and are known to predict different separator geometries for the same operating conditions. These procedures were constrained to allow optimisation of the design but details of the constraints applied on the rational for their application are not available. To better understand these constraints, the two procedures for sizing a three - phase horizontal separator equipped with weir plate were investigated. Each procedure was used to calculate the geometries for three different sets of flowrates namely; fixed oil with varying gas and water, fixed water with varying gas and oil and finally fixed gas with varying oil and water. The calculated geometries determined from each procedure were then investigated using ANSYS Fluent to determine the separation achieved. To ensure that the ANSYS Fluent simulations accurately defines the separation process, a small scale industrial separator was modelled. Simulation results in terms of the separator outlet quality predicted that the separator designed using Arnold and Stewart procedure has a greater separation efficiency than that designed by Svrcek and Monnery.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.