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Preventing the Loss, Improving the Properties of the Circulating Material to Seal Fractures and a Depleted Section of the Well
Hongtao Zhou,
Urinov Abrorbek Axrorovich,
Liu Wei
Issue:
Volume 3, Issue 2, December 2019
Pages:
34-38
Received:
24 July 2019
Accepted:
16 August 2019
Published:
29 August 2019
Abstract: The loss of circulation is an extremely unhealthy phenomenon for drilling, as the liquid solution leaving in the reservoir often leaves the entire drilled breed in the borehole and, in most cases, all the large particles in the solution itself. The settling masses are compacted and can create around the drill tool dense shell and also cause so-called clamp tool-a phenomenon when to remove the drill pipe poses great difficulties. The methods devise in the current research for loss of circulation or eliminated are a reduction of mud density until its hydrostatic pressure becomes equal to the reservoir and Pumping Mudpack with a high concentration of clogging additives in the absorption zone. In addition, the clogging materials to combat the loss of circulation can be used as additives in circulating drilling mud in the drilling of sediment prone to absorption. For the control of absorption, it is possible to use saw dust, flaky and granulated materials or a mixture of all three [1-6]. The flaky materials include cellophane, mica, the husk of sunflower seeds cotton, nut shells. The granulated materials include grinding rubber or asbestos, asphalt. This method differs from other methods in that in order to prevent the loss of the drilling solution to the composition of the chemical compound can be improved by increasing the agent's viscosity in cracks or pores clogging. A series of experiments was conducted to determine the optimal viscosity of the agent, consisting of urea formaldehyde with ammonium sulfate and bentonite. Ammonium sulfate is added to urea formaldehyde in the ratio of 1/5. In a series of experiments, the ratio of chemicals was increased properly. Measurement of solution viscosity was performed by rheometer up to 500MPa. Since there are errors in Rheometer after 500MPA, the measurement of viscosity began by hand with the help of 200ml of the test tube, weights and steel ball. The obtained results satisfied the requirement for the loss of the chemical of drilling mud. Thus, on the basis of the experiments, it was found that to prevent the loss of the drilling solution to improve the composition of the chemical compound by increasing the viscosity of the agent. This will save the amount of mud and expensive additives save time for drilling and prevent clogging of potentially productive drilling areas.
Abstract: The loss of circulation is an extremely unhealthy phenomenon for drilling, as the liquid solution leaving in the reservoir often leaves the entire drilled breed in the borehole and, in most cases, all the large particles in the solution itself. The settling masses are compacted and can create around the drill tool dense shell and also cause so-call...
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On Upward Swirling Liquid Film in Gas-liquid Pipe Compact Separator
Issue:
Volume 3, Issue 2, December 2019
Pages:
39-45
Received:
24 July 2019
Accepted:
13 August 2019
Published:
29 August 2019
Abstract: This paper presents experimental findings on upward swirling liquid film for both single-phase and two-phase gas-liquid flow in a vertical gas-liquid cyclonic separator. The upward swirling liquid film is one dynamic phenomenon that occurs in pipe cyclonic separator. The upward swirling of the liquid film in the upper part of the cyclonic separator is the primary source of liquid entrainment into the gas core. Liquid entrainment from the separator wall into the gas core is the main cause of liquid carryover. Liquid carryover is the major disadvantage of the gas-liquid pipe cyclonic separator. Various researchers in the past have identified the effect of this phenomenon on the performance of gas-liquid pipe cyclonic separator, but not many efforts have been made to study the phenomenon in detail. In this work, the upward swirling liquid film height was measured using a meter rule, while the thickness of the swirling liquid film was estimated using the void fraction that was measured with electrical resistance tomography (ERT). The experimental results show that the height attained by the upward swirling liquid film is a function of the film thickness and inlet gas velocity. The results also showed that the horizontal inlet pipe produces the highest liquid film height when compared with the inclined inlet pipe. By keeping the liquid flow rate constant and increasing gas flow rate, a maximum liquid film height was observed, afterwards, the liquid film height decreases within increasing gas flow rate.
Abstract: This paper presents experimental findings on upward swirling liquid film for both single-phase and two-phase gas-liquid flow in a vertical gas-liquid cyclonic separator. The upward swirling liquid film is one dynamic phenomenon that occurs in pipe cyclonic separator. The upward swirling of the liquid film in the upper part of the cyclonic separator...
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Suitability of Some Nigerian Barites in Drilling Fluid Formulations
Ugochukwu Ilozurike Duru,
Anthony Kerunwa,
Ifeanyi Omeokwe,
Nnaemeka Uwaezuoke,
Boniface Obah
Issue:
Volume 3, Issue 2, December 2019
Pages:
46-59
Received:
10 September 2019
Accepted:
11 October 2019
Published:
24 October 2019
Abstract: In order to counter-balance the formation pressure, the drilling mud is weighted up using a chemical additive, usually Barite. The usability of locally sourced Nigerian Barites on the major types of drilling fluids in conventional conditions is presented. Water-Based mud, Oil-Based mud and Synthetic-Based mud formulations with locally sourced Barite were tested according to the American Petroleum Institute recommended practices. Hole cleaning capabilities of the formulations by the use of Cutting Carrying Index (CCI) and Cutting Concentration (CC) as indicators showed that Osina, Gabu and Obubra Nigerian Barites are suitable for use as drilling fluid additives; with Cutting Carrying Index in the range of 23.27 to 120.54 for Water-Based mud, 0.89 to 3.98 for Oil-Based mud and 0.45 to 1.13 for Synthetic-Based mud. The Cutting Concentration of average of 4.15 vol. % at 355gpm and 300ft/hr ROP for Water-Based mud, Oil-Based mud and Synthetic-Based mud, with MAXROP of 364ft/hr under the same conditions was recorded. Moreso, laminar flow regime in the annulus was predicted for all the mud types under the same conditions and temperatures specified, based on a MATLAB programme developed to perform the computation. Cutting Carrying Index for water based mud decreased from ambient, 120°F, 180°F to 240°F compared with API mud used as control sample.
Abstract: In order to counter-balance the formation pressure, the drilling mud is weighted up using a chemical additive, usually Barite. The usability of locally sourced Nigerian Barites on the major types of drilling fluids in conventional conditions is presented. Water-Based mud, Oil-Based mud and Synthetic-Based mud formulations with locally sourced Barit...
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Mathematical Approach to Determination of Optimum Oil Production Rate in Oil Rim Reservoirs
Obibuike Ubanozie Julian,
Ekwueme Stanley Toochukwu,
Ohia Nnaemeka Princewill,
Igwilo Kevin Chinwuba,
Igbojionu Anthony Chemazu,
Kerunwa Anthony
Issue:
Volume 3, Issue 2, December 2019
Pages:
60-67
Received:
28 September 2019
Accepted:
25 October 2019
Published:
11 November 2019
Abstract: Oil rim reservoirs present unique problems during production. This is because of the proximity of the water and/or gas to the oil in the pay zone leading to phase distortion due to pressure disequilibrium during production of the oil. The resultant effect is early water/gas breakthroughs which ultimately lead to increased well operational cost, damage to production equipment and eventually to early loss of the well. Production rate becomes crucial as it directly or indirectly affects the overall recovery efficiency from the well. Low rate production signifies longer well production period due to delayed breakthrough time but at the expense of higher well operational cost per unit volume of oil produced, while higher rate production signifies higher oil volume per unit cost of well operation but with increased risk of losing the well due to water/gas breakthrough. Operators produce at a rate deemed economic in order to make profits. Most economic rates are higher than the critical rate which is the rate considered that coning would be maximally delayed. To optimize production, it is necessary to recover most of the fluid from the reservoir before abandonment. Higher recovery factors means that less volume of fluid is left in the reservoir at abandonment. The optimum oil production rate is the best economic oil rate that would result to the highest recovery factor obtainable from that well. The question is what rate is considered optimal and how can it be calculated? This work presents a mathematical model solution for the calculation of the optimum oil production rate. It takes cognizance of the recovery factor and the time value of money and present an analytical model to calculate the optimum oil production rate. From the work the optimum oil production rate was calculated to be 918.63stb/d while the critical oil rate was calculated to be 20.17stb/d.
Abstract: Oil rim reservoirs present unique problems during production. This is because of the proximity of the water and/or gas to the oil in the pay zone leading to phase distortion due to pressure disequilibrium during production of the oil. The resultant effect is early water/gas breakthroughs which ultimately lead to increased well operational cost, dam...
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Mathematical Model for Time of Leak Estimation in Natural Gas Pipeline
Obibuike Ubanozie Julian,
Ekwueme Stanley Toochukwu,
Ohia Nnaemeka Princewill,
Igbojionu Anthony Chemazu,
Igwilo Kevin Chinwuba,
Kerunwa Anthony
Issue:
Volume 3, Issue 2, December 2019
Pages:
68-73
Received:
11 October 2019
Accepted:
5 November 2019
Published:
11 November 2019
Abstract: The ability to detect leak is crucial in pipeline fluid transport operations. Leaks will inevitably occur in pipelines due to wide range of uncertainties. A good leak detection system should not only be able to detect leak but also accurately estimate the actual time of leak occurrence. This will enable proper estimation of the fluid loss, from the pipeline before shut-in of the pipeline or before remedial actions were carried out on the pipeline which ultimately will help quantified the degree of financial or environmental implications resulting from the leak incidence. This paper gives a new model for the estimation of the time of leak in natural gas pipeline. The idea for the model hinges on the notion that the time of response of most pipeline alarm are not necessarily the time actual time the leak occurred. Period of lapse depends on the accuracy, sophistication of the alarm system and volume of leak it is capable of detecting. Most alarm systems respond at later times than the time the leak occurred. Quantification of fluid loss volume demands that the actual time of leak occurrence be determined, this means that the time the leak occurred must be calculated accurately. The model was simulated using the Matlab software. The results show that the model is highly accurate when tested with field data.
Abstract: The ability to detect leak is crucial in pipeline fluid transport operations. Leaks will inevitably occur in pipelines due to wide range of uncertainties. A good leak detection system should not only be able to detect leak but also accurately estimate the actual time of leak occurrence. This will enable proper estimation of the fluid loss, from the...
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Contribution to the Study on the Possibility of the Development of the Upper Cenomanian Reservoir of the Tshiende Field
El-Richard Molodi Empi,
Dominique Wetshondo Osomba,
Joel Kabesa Kilungu,
Joseph Ntibahanana Munezero,
Junior Mbambo Bokitshi,
Kyria Museghe Kyria,
Romulus Mawa Tuzingila,
Link Bukasa Muamba
Issue:
Volume 3, Issue 2, December 2019
Pages:
74-84
Received:
14 October 2019
Accepted:
4 November 2019
Published:
10 December 2019
Abstract: In order to carry out hydrocarbon production in the basement, a drilling must be carried out and the latter crosses several layers or formation until reaching the desired objective. At the beginning of the production, the well will have a natural pressure and the oils in a reasonable quantity which will allow to make an exploitation but over time the pressure decreases and the production of oil leaves room for the production of water to show the end oils and in most cases this well is converted from producing well into an injector well to feed other wells or repackage. In fact, the Tshiende field comprises three reservoirs (Cenomanian, Pinda and Vermelha) that produce and the Cenomanian only produces in its lower horizon. The entire well passes through the Cenomanian reservoir to reach the other two reservoirs. To contribute to the understanding of the geological complexity of the reservoirs of this field, we focused our study on the Cenomanian reservoir. This reservoir did not produce in its superior horizon in the Cenomanian after several tries, but Produces in other fields that the Tshiende field, and that sometimes constitutes the main reservoir in the field Muanda. A new production test in the Ts-27 well began on 02/01/2019 in the Cenomanian dedicated upper part using other technique than the previous ones. This has had to prove the feasibility of producing this unknown reservoir. The decision was made to re-evaluate the UC potential and to propose wells to perforate to depend on their positions and history. After an extensive review of Tshiende's potential for superior Cenomanian production, a development program is proposed. Four workovers are proposed to develop the higher Cenomanian potential in the TS-29, TS-22, TS-02 and TS-13 wells.
Abstract: In order to carry out hydrocarbon production in the basement, a drilling must be carried out and the latter crosses several layers or formation until reaching the desired objective. At the beginning of the production, the well will have a natural pressure and the oils in a reasonable quantity which will allow to make an exploitation but over time t...
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Economics of Gas-to-Liquids (GTL) Plants
Ekwueme Stanley Toochukwu,
Izuwa Nkemakolam Chinedu,
Obibuike Ubanozie Julian,
Kerunwa Anthony,
Ohia Nnaemeka Princewill,
Odo Jude Emeka,
Obah Boniface
Issue:
Volume 3, Issue 2, December 2019
Pages:
85-93
Received:
21 October 2019
Accepted:
23 November 2019
Published:
13 December 2019
Abstract: This work evaluates the economics of GTL plant using two synthesis gas methods. The first method called the base case utilizes oxygen as fuel for combustion of natural gas, while the proposed case uses steam/CO2 instead of Oxygen. The aim is to ascertain a more economically viable GTL configuration for an optimal GTL process. The associated flare gas at Egbema production sites in the Niger Delta has been chosen as case study. The gas flowrate is 50MMscfd of raw natural gas which was pre-treated before being fed into the main GTL plant. The liquid yield result shows that the proposed method has a liquid yield of 5730b/d over the 5430b/d gotten from the base case representing an increase in product yield of 5.5%. The economic analyses show a quicker pay-out time of 4.9 years from the proposed model compared to 5.9 years from the base case. Using the proposed method gave an annual cashflow increase of 20.9% and NPV increase of 59.7% at 10% discount rates. Also the DCF-ROR from the proposed method was 20.3% compared to 16.6% gotten from the base method. Thus the proposed method is more profitable in terms of NPV. The project is recommended for application in the Niger Delta stranded and remote gas locations that have before now been subjected to flaring.
Abstract: This work evaluates the economics of GTL plant using two synthesis gas methods. The first method called the base case utilizes oxygen as fuel for combustion of natural gas, while the proposed case uses steam/CO2 instead of Oxygen. The aim is to ascertain a more economically viable GTL configuration for an optimal GTL process. The associated flare g...
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Gas-to-Liquids (GTL) Plant Optimization Using Enhanced Synthesis Gas Reforming Technology
Izuwa Nkemakolam Chinedu,
Obah Boniface,
Ekwueme Stanley Toochukwu,
Obibuike Ubanozie Julian,
Kerunwa Anthony,
Ohia Nnaemeka Princewill,
Odo Jude Emeka
Issue:
Volume 3, Issue 2, December 2019
Pages:
94-102
Received:
21 October 2019
Accepted:
23 November 2019
Published:
13 December 2019
Abstract: This paper evaluates method for optimisation of GTL plant using Steam/CO2 reforming for syngas generation. Extensive modelling of GTL plant has been done. Two cases were considered during the simulation of the GTL plant. The first case was the use of oxygen gas as the feed reactant gas using an auto-thermal reformer for the production of synthesis gas. The alternative case which is the proposed method uses CO2 in lieu of oxygen for the production of synthesis gas. CO2 method was chosen because of its cheap availability and the ability to be recycled from purge gas and reused reducing pollution. Honeywell’s Unisim software was used for the simulation and the Peng Robinson equation of state was chosen as the fluid property package. The simulation was done unit by unit and integration of all units was made. The synthesis gas unit was simulated in Unisim as a conversion type reactor using two separate reactors while three equilibrium reactors were used to control the water gas shift reaction to maintain favourable H2/CO ratio. The FT reactor was modelled as a multi-tubular bed reactor and simulated as a plug flow reactor (PFR) in Unisim using heterogeneous catalytic reaction type. Technical and economic performances were analyzed for both methods. The technical analyses revealed that the proposed steam/CO2 method gave a H2/CO ratio of 2.17 as against the 2.21 gotten for the ATR. Furthermore, the carbon efficiency of the two methods revealed 77.68% and 92.17% for base case and the proposed methods respectively showing that the proposed case has higher efficiency. The liquid yields show that the proposed method has a liquid yield of 5730b/d over the 5430b/d gotten from the base case representing an increase in product yield of 5.5%.
Abstract: This paper evaluates method for optimisation of GTL plant using Steam/CO2 reforming for syngas generation. Extensive modelling of GTL plant has been done. Two cases were considered during the simulation of the GTL plant. The first case was the use of oxygen gas as the feed reactant gas using an auto-thermal reformer for the production of synthesis ...
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