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Modelling Flare Gas Recovery System for Recovery and Utilization of Stranded Associated Gas in the Niger Delta
Mathew Chidube Udechukwu,
Boniface Obah,
Charley Iyke Anyadiegwu,
Stanley Onwukwe,
Ubanozie Julian Obibuike,
Stanley Toochukwu Ekwueme
Issue:
Volume 10, Issue 1, January 2022
Pages:
1-16
Received:
20 November 2021
Accepted:
8 December 2021
Published:
8 January 2022
Abstract: In this paper, the modeling of a flare gas recovery system (FRGRS) for the recovery and utilization of stranded associated gas in the Niger Delta region of Nigeria was investigated. The gas recovery system is a novel modular plant with several integrated units and operational features. The FGRS was modeled for the recovery, treatment, processing of stranded associated gas. Two cases were considered, one was the compression of the treated gas from the FGRS to pipeline as sales gas while the other was the conversion of the treated gas to premium transport liquids by gas-to-liquids technology. 25 MMScfd of recovered stranded associated flare gas was used as feedstock and it yielded 23.22 MMscfd of treated natural gas and 1.77 Mscfd of acid gas. The treated gas met all pipeline sales gas specifications. In modeling the GTL plant, an autothermal reforming method of synthesis gas production was used and an H2/CO ratio of 2.33 was recovered which was acceptable for Fisher-Tropsch reaction downstream. The entire GTL plant simulation was modeled in Honeywell Unisim with Peng-Robinson as the fluid property package. Gas-to-liquids (GTL) product produced from the 23.22 Mscfd treated gas fed to the GTL plant were 2350 b/d of liquid transport fuels comprising 1100 b/d of diesel and 1250 b/d of gasoline. Economic analyses revealed thata net present value (NPV) of US$ 109.9 million was realized from the sales of GTL liquids while an NPV of US$58.5 million was realized from the sales of pipeline quality gas. Thus, the sales of GTL products represent an increase in NPV of 87.8% when compared with that of pipeline gas. However, the Pay-out time (POT) for pipeline sales gaswas 1.16 years, the internal rate of return (IRR) was 86% while the profit-per-dollar invested was 16.18. Furthermore, the pay-out time for GTL product sale was 5.29 years, the internal rate of return was 18.3% and the profit-per-dollar invested was 2.78. The project showed that the gas may be sold outright (as pipeline gas) if the market was available and in the absence of a ready market for the gas, the gas could be converted to liquids that are easier to store and have greater market potentials in the long run.
Abstract: In this paper, the modeling of a flare gas recovery system (FRGRS) for the recovery and utilization of stranded associated gas in the Niger Delta region of Nigeria was investigated. The gas recovery system is a novel modular plant with several integrated units and operational features. The FGRS was modeled for the recovery, treatment, processing of...
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Development of Proxy Models for Predicting and Optimizing the Time and Recovery Factor at Breakthrough During Water Injection in Oil Reservoirs
Anthony Ogbaegbe Chikwe,
Onyebuchi Ivan Nwanwe,
Obinna Stanley Onyia,
Ndubuisi Uchechukwu Okereke,
Jude Emeka Odo
Issue:
Volume 10, Issue 1, January 2022
Pages:
17-30
Received:
28 December 2021
Accepted:
20 January 2022
Published:
16 February 2022
Abstract: Numerical reservoir simulation studies can be used to plan water injection projects to delay time and maximize oil recovery at water breakthrough which is time-consuming and computationally expensive. Combining computationally inexpensive proxy models and optimization algorithms is a solution to this problem. In this study, the Box-Behnken design method and response surface methodology were used to develop two proxy models which showed the relationship between time and recovery factor at water breakthrough with six independent variables namely porosity, horizontal permeability, water viscosity, bottom-hole pressure, water injection rate and vertical permeability. A comparison of actual and predicted values for time and oil recovery factor at water breakthrough was found to be in good agreement with each other. An average absolute percentage error of 2.038% and 1.217%, a root mean square error of 0.08 and 0.0000988, and coefficients of determination, R2 of 0.9984 and 0.9946 were obtained for time and recovery factor at water breakthrough respectively. These are indications that the developed models are accurate, valid, and reliable. The models were further validated by comparing the actual and predicted water breakthrough time and recovery factor at water breakthrough using input variables that were not used in model development. These were also in close agreement with each other. The MATLAB multi-objective genetic algorithm was used to determine at a specific average porosity and permeability value, the best optimum controllable variables that maximized the objective functions. These were found to be 10.8978 years and 0.786 respectively and agreed with simulation results obtained using similar input parameter values.
Abstract: Numerical reservoir simulation studies can be used to plan water injection projects to delay time and maximize oil recovery at water breakthrough which is time-consuming and computationally expensive. Combining computationally inexpensive proxy models and optimization algorithms is a solution to this problem. In this study, the Box-Behnken design m...
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Evaluation and Reactivation Strategy of Shut-In Wells Due to High Water Cut to Improve Oil Production in Bayu Field: Case Study of Bayu-N3 Well
Dedy Kristanto,
Dadang Rukmana,
Agus Amperianto,
Windyanesha Paradhita
Issue:
Volume 10, Issue 1, January 2022
Pages:
31-41
Received:
16 January 2022
Accepted:
4 February 2022
Published:
16 February 2022
Abstract: Bayu-N3 was being shut-in (S/I) due to excessive water production (high water cut well) as the main cause of the high daily production decline of the well. Therefore, an integrated analysis was conducted to identify the source of excessive water production and handle the problem. The reactivation strategy of Bayu-N3 was well planned to solve and optimize the oil production of the well. Based on integrated analysis of Chan’s diagnostic plot and cement evaluation log (CBL-VDL-USIT) data, the source of excessive water production at Bayu-N3 is water channeling, caused by the free pipe condition as the result of poor cement bonding between the casing and the formation. To handle the water channeling problem, remedial cementing was conducted to repair the cement bonding quality. Based on the C/O log evaluation at Bayu-N3 as the reactivation well candidate, there are six potential oil zones to be produced. The reactivation strategy was executed by perforating at interval 6544-6564 ft-MD and resulting 1602 BOPD with 0% of water cut. The economic analysis of the reactivation shows that Bayu-N3 well gives 5153 MUSD of NPV and 538% of IRR with one month and 29 days of POT. It is shows that the reactivation strategy of Bayu-N3 is technically and economically able to improve the oil production and gives good positive economic indicators. Furthermore, the successful of reactivation strategy in Bayu-N3 well could be used as reference to be implemented for other candidate wells in Bayu Field.
Abstract: Bayu-N3 was being shut-in (S/I) due to excessive water production (high water cut well) as the main cause of the high daily production decline of the well. Therefore, an integrated analysis was conducted to identify the source of excessive water production and handle the problem. The reactivation strategy of Bayu-N3 was well planned to solve and op...
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Characterization of Local Clay for Drilling Mud Production
Onyejekwe Ifeanyichukwu Michael,
Duru Ugochukwu Ilozuruike,
Obibuike Ubanozie Julian,
Odo Jude Emeka,
Nnanna Okoli
Issue:
Volume 10, Issue 1, January 2022
Pages:
42-49
Received:
10 January 2022
Accepted:
3 February 2022
Published:
25 February 2022
Abstract: Oil companies’dealing with drilling operations in Nigeria often spends millions of dollars in importation of bentonite for its operations as a result of its importance and high demand. As a result of this, attempt to source for local substitute has been initiated, which if successful would save the nation from this huge capital flight. In this study, a sample of Umuna local clay deposit was evaluated for drilling fluid application. The viscosity and filtration loss was analyzed and it’s far below that of the imported bentonite. The properties of the local clay was improved by addingmaterials such as HV-CMC, Drispac polymer and bentonite extenders to the formulated mud to enhance its viscosity and filtration loss Also the shearing speed was increased, but the used speed is limited to practical shearing speed. Theclay yield and characterization of the beneficiated samples show that the treated local clay is slightly comparable to the imported bentonite. The Calcium Exchange Capacity (CEC) result for the clay samples fall within the 70 – 150 Meq/100g. This result further suggests that the analyzed clay is of montimorillonite family, with traces of illite which is good for drilling mud production. The obtained results from this study indicates that the filtration loss and plastic viscosity for the analyzed clay samples were generally far from comparing with the imported bentonite, but through beneficiation, they were able to compare with the imported bentonite.
Abstract: Oil companies’dealing with drilling operations in Nigeria often spends millions of dollars in importation of bentonite for its operations as a result of its importance and high demand. As a result of this, attempt to source for local substitute has been initiated, which if successful would save the nation from this huge capital flight. In this stud...
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