-
Evaluation of Wave Characteristics in Annular Flow in Horizontal Pipes
Issue:
Volume 8, Issue 1, January 2020
Pages:
1-9
Received:
9 November 2019
Accepted:
2 December 2019
Published:
10 January 2020
Abstract: Annular flow experiments in horizontal flow in pipes were conducted with emphasis on wave characteristics (wave velocity, wave frequency) and liquid film thickness. The experiments were conducted using water/air in a 0.0504m pipe diameter with a total flow loop length of 28.68m. Liquid film thickness in all the flow matrix in this study, were observed to be decreasing with increase in gas velocity while increasing with increase in liquid velocity. The decreasing tendency with superficial gas velocity was because of liquid entrainments which were accounted. Pan and Hanratty correlation for liquid entrainment was chosen because it gave the most realistic results among other correlations from the experimental data. Wave velocity and wave frequency were presented to be increasing with increase in superficial gas velocity in annular flow. For wave frequency, it was observed that both superficial liquid and gas velocities have great impact on it. In annular flow in horizontal pipe, it was also observed that the lower the superficial liquid velocity, the lower the amplitude and the higher the wave frequency. This indicates that at low liquid velocity, more ripple waves occurred and at this time more energy were dissipated which resulted to the high frequency observed in this study. However, several correlations where compared with the obtained wave frequency in this study, but [2] preferably matched better as the superficial liquid velocity increases from 0.0903m/s to 0.1851m/s.
Abstract: Annular flow experiments in horizontal flow in pipes were conducted with emphasis on wave characteristics (wave velocity, wave frequency) and liquid film thickness. The experiments were conducted using water/air in a 0.0504m pipe diameter with a total flow loop length of 28.68m. Liquid film thickness in all the flow matrix in this study, were obser...
Show More
-
Automated Pipe Handling System Suitable for Retrofitting Servicing Rigs in China
Fang Tai’an,
Zhou Zhixiong,
Wu Changliang,
Lv Juan,
Zuo Weidong
Issue:
Volume 8, Issue 1, January 2020
Pages:
10-16
Received:
17 October 2019
Accepted:
13 November 2019
Published:
13 January 2020
Abstract: With the development of automated drilling technology, various automated pipe handling devices are constantly being introduced. It is an inevitable trend to apply these equipment on new drilling rigs, while it is also an important work to apply these new technologies and equipment to a large number of servicing rigs. At present, most of the existing drilling rigs in China do not have automatic pipe handling system. It is urgent to carry out automation retrofitting due to the poor field working environment, hard labor, poor safety and low efficiency. In the paper, the current status of the automated pipe handling system is firstly introduced, and the advantages and disadvantages of these automated pipe handling systems are expounded. Then the comparative analysis of applicability, complexity and the retrofitting cost of the automated pipe picked-up and laid-down drilling floor device, pipe handling device on racking board and the offline stand building device in both domestic and foreign are made. Finally, the suitable types of automated pipe handling system can be used to retrofit servicing rigs in China are pointed out. Cameron's automatic up-and-down rig device, Weatherford's racking board automatic pipe handling system and National Drilling Company's offline stand building system are most suitable for the automation retrofitting of servicing rigs. The results show that, these automated pipe handling systems can not only reduce the labor of field operators, improve pipe handling efficiency, reduce the retrofitting workload of servicing rig, but also save retrofitting costs. The retrofitted servicing drilling rigs will be with new vitality and play a greater role in the development of ultra-deep wells and unconventional oil and gas in China.
Abstract: With the development of automated drilling technology, various automated pipe handling devices are constantly being introduced. It is an inevitable trend to apply these equipment on new drilling rigs, while it is also an important work to apply these new technologies and equipment to a large number of servicing rigs. At present, most of the existin...
Show More
-
Experimental Investigation of Pipeline Corrosion in a Polluted Niger Delta River
Odutola Toyin Olabisi,
Amobi Chukwuka
Issue:
Volume 8, Issue 1, January 2020
Pages:
17-21
Received:
16 December 2019
Accepted:
9 January 2020
Published:
21 January 2020
Abstract: Several networks of pipelines in Nigeria oil and gas industry have failed catastrophically in the last two decades because most oil pipelines operate in a corrosive environment and transport corrosive fluids. This research experimentally investigates the corrosion of a carbon steel pipeline immersed in a typical Niger Delta Offshore Environment. The experiment was carried out using the gravimetric (weight loss) method. The carbon steel coupon was immersed in a sample of water collected from the Niger Delta sea and in seawater polluted by 0.5mol/dm3, 1.0mol/dm3, 1.5mol/dm3 and 2.0mol/dm3 tetraoxosulphate (VI) acid respectively. The coupons were retrieved and examined at 4-hour interval. It was discovered that in an unpolluted state, the seawater was not corrosive. However, when polluted by 0.5mol/dm3, 1.0mol/dm3, 1.5mol/dm3 and 2.0mol/dm3 tetraoxosulphate (VI) acid, corrosion occurred. The highest rate of corrosion was observed in the coupon dipped into the seawater sample polluted by 2.0mol/dm3 of tetraoxosulphate (vi) acid and the lowest corrosion rate observed in the least polluted seawater 0.5mol/dm3. Corrosion rate increased with increasing pollutants; therefore, it is imperative for oil operators to carefully dispose of their waste to prevent rapid corrosion of subsea pipelines and other offshore facilities.
Abstract: Several networks of pipelines in Nigeria oil and gas industry have failed catastrophically in the last two decades because most oil pipelines operate in a corrosive environment and transport corrosive fluids. This research experimentally investigates the corrosion of a carbon steel pipeline immersed in a typical Niger Delta Offshore Environment. Th...
Show More
-
Mathematical Approach to Determination of the Pressure at the Point of Leak in Natural Gas Pipeline
Ubanozie Julian Obibuike,
Anthony Kerunwa,
Mathew Udechukwu,
Remmy Chindu Eluagu,
Anthony Chemazu Igbojionu,
Stanley Toochukwu Ekwueme
Issue:
Volume 8, Issue 1, January 2020
Pages:
22-27
Received:
30 December 2019
Accepted:
13 January 2020
Published:
10 February 2020
Abstract: In this paper, a model is developed for the estimation of the pressure at the point of leak in a natural gas pipeline experiencing leak. The model is developed by comparing two equations developed for leak localization in natural gas pipeline corresponding to the upstream and the downstream sections of the pipeline respectively. The determination of the pressure at the point of leak which is the dominant parameter for the two models ensures the accuracy and equality of the two leak localization equation regardless of the section of the pipeline considered. The model for the point of leak develops helps to monitor pipeline pressure profile for the leak and the no leak case and helps to detect the exact point of leak in the pipeline depicted by the pressure reductions gotten by comparing the pressure profile of the no leak and the leaking pipeline cases. In the work three cases were considered. In each of the cases, the pressure at the point of leak were estimate with the corresponding location where the leak occurred. It is also realized as expected that the calculated pressures at the point of leak were lower than the expected pressures at the same point if the pipeline were not subject to leak. The results gotten show that the pressure at the point of leak for the three cases are 738 psi, 678.33 psi and 933.89 psi for case 1, case 2 and case 3 respectively. These pressure values occurred at locations 139.5 miles, 86.48 miles and 34.94 miles from the inlet point for case 1, case 2 and case 3 respectively.
Abstract: In this paper, a model is developed for the estimation of the pressure at the point of leak in a natural gas pipeline experiencing leak. The model is developed by comparing two equations developed for leak localization in natural gas pipeline corresponding to the upstream and the downstream sections of the pipeline respectively. The determination o...
Show More
-
Utilization of Stranded Associated Flare Gases for Electricity Generation in Situ Through Gas-to-Wire in the Niger Delta
Anthony Kerunwa,
Stanley Toochukwu Ekwueme,
Ubanozie Julian Obibuike
Issue:
Volume 8, Issue 1, January 2020
Pages:
28-34
Received:
6 February 2020
Accepted:
19 February 2020
Published:
28 February 2020
Abstract: The large volume of stranded associated gas in the Niger Delta which has sadly been flared holds great prospect in addressing Nigeria’s electricity problem if properly harnessed. The predominance of central electricity production system has over the years shown incapability in generating enough electricity needed by the Nigeria populace. Even with the little generated, large losses are seen as they are transmitted from areas of generation to areas of consumption through the national grid system. A new system of electricity system has to be initiated capable of generating electricity even in smaller amounts for a geographical location. This power when generated and utilized insitu will save losses from transmission lines serve areas not previously contacted by the grid system. In this work, gas-to-wire technology is used to convert 5MMscfd of stranded associated flare gas in Ohaji North in the Niger delta to electricity using combine cycle gas turbine. The gas volume was sufficient for the production of 44.2 MW of electricity per day. Economic evaluation of the project gives a Net present value at 10% discount rate of USD 108150066, the pay-out-time of 2.69 years and a discounted cashflow rate of return of 37 years making the project a highly profitable one recommended for Nigeria as a solution to the poor electricity generation problem.
Abstract: The large volume of stranded associated gas in the Niger Delta which has sadly been flared holds great prospect in addressing Nigeria’s electricity problem if properly harnessed. The predominance of central electricity production system has over the years shown incapability in generating enough electricity needed by the Nigeria populace. Even with ...
Show More
