Day 2 :
Keynote Forum
Xiaohui Wang
China University of Petroleum, China
Keynote: New risk assessment method of gas influx based on five example wells in China
Time : 10:00-10:40
Biography:
Xiaohui Wang has her expertise in evaluation and passion for improving the risk assessment in deepwater drilling. Her open and contextual evaluation model based on hidden Markov model creates new pathways for improving the accuracy of the gas cut evaluation. She has built this model after years of experience in research, evaluation, and administration in educational institutions.
Abstract:
Gas cut risk assessment is the premise of well control schemes; the evaluation method used is the key technology in the risk assessment process, which directly affects the final effect of well control. In this paper, a gas invasion risk assessment system based on analytic hierarchy process (AHP) and hidden Markov model (HMM) is studied and the feasibility of the system is verified using fifteen actual wells. Firstly, this research starts from the interval judgment matrix and approximates the interval judgment matrix to the general digital judgment matrix. Then it forms an AHP with automatic correction judgment matrix and obtains the approximate weight of each element. Thus, a gas trapping evaluation system based on HMM was established. Realtime dynamic risk assessment was carried out with HMM and its results were compared with the results of AHP. The experimental results show that the method of general digital judgment matrix can be used to solve the problem that the traditional AHP method often results in inconsistency in the measurement of multi-factor weight and improves the accuracy and trust worthiness of the evaluation results. Through the collection of real-time data in the drilling process, the HMM method is used to calculate the risk situation of each node and the monitoring signal data is updated in real time; then the original data is provided for the implementation evaluation system based on the HMM method. Combined with the AHP evaluation results, the degree of the risk can be described more accurately, thus having higher assessment accuracy. The real-time risk assessment method based on HMM and AHP proposed in this research can solve the above problems effectively, thus reducing the harm of gas invasion and save the drilling cost. Recent Publications 1. Yin H, Liu P and Li Q (2015) A new approach to risk control of gas kick in high-pressure sour gas wells. Journal of Natural Gas Science & Engineering 26:142???148. 2. Chen P and Ma T (2014) Research status of early monitoring technology for deep water drilling overflow. J. Acta Petrolei Sinica 35(3):602???612. 3. Hauge E, Aamo O M and Godhavn J M (2013) A novel model-based scheme for kick and loss mitigation during drilling. Journal of Process Control 23(4):463???472. 4. Mcconnell D R, Zhang Z and Boswell R (2012) Review of progress in evaluating gas hydrate drilling hazards. Marine and Petroleum Geology 34(1):209???223. 5. Alhuthali A H, Datta Gupta A and Yuen B (2010) Optimizing smart well controls under geologic uncertainty. Journal of Petroleum Science & Engineering 73(1???2):107???121.
Keynote Forum
Ricardo Medronho
Federal University of Rio de Janeiro, Brazil
Keynote: Dimensioning hazardous areas in a crude oil pump facility by computational fluid dynamics and by recommended practice guidelines for classifying locations: A comparison
Time : 10:40-11:20
Biography:
Prof. Ricardo A. Medronho is a full professor at the Chem. Eng. Dept. of the Federal Univ. of Rio de Janeiro. He is a specialist in CFD applied to the oil and gas industry and has supervised more than 50 MSc and DSc students.
Abstract:
Accidents related to oil and gas plants are a concern because despite having intermediate frequency of occurrence, the consequences are severe, with intermediate fatality potential and high potential of economic losses. One of the issues noted to this risk is related with electrical facilities and equipment with components operating with flammable products, which can act as source of ignition, generating severe accidents. So, an appropriate hazardous area definition is necessary to avoid these types of accidents in places with explosive atmospheres. This study aims to define a hazardous area of a crude oil pump facility through numeric simulation with computational fluid dynamics (CFD), and compare the results to the recommended practice guidelines used to define the hazardous areas. These guidelines used as reference to define hazardous areas are the NFPA 497 and API 505. For the computational fluid dynamics, the CFD package from Ansys was employed. The comparison of the hazardous areas results based on the guidelines overestimate these areas when compared to the CFD results. It may be concluded that the guidelines are conservative criteria, so the standards are sufficiently safe. Nevertheless, the use of CFD may support projects as an auxiliary tool of risk analysis. Recent Publications 1. Bozek A, Anhalt J and Chin J (2015) The use of infrared emission detection and fugitive emission quantification technologies as a basis for hazardous area classification design. IEEE Transactions on Industry Applications. 51(1):142-147. 2. Nagaosa R S (2014) A new numerical formulation of gas leakage and spread into a residential space in terms of hazard analysis. Journal of Hazardous Materials. 271:266-274. 3. Gomes E G, Medronho R A and Alves J V B (2014) Gas detector placement in petroleum process unit using computational fluid dynamics. International Journal of Modeling and Simulation for the Petroleum Industry. 8:17-24. 4. Zhu Y et al. (2015) Analysis and assessment of the Qingdao crude oil vapor explosion accident: lessons learnt. Journal of Loss Prevention in the Process Industries. 33:289-303.
- Advances in Petroleum Engineering |Unconventional Gas and Oil Resources |Health, Safety & Risk in an Organizational Context | Petroleum Science And Technology |Enhanced Oil Recovery And Refining
Location: olimpica 3+4
Chair
Xiaohui Wang
China University of Petroleum, China
Co-Chair
Ricardo Medronho
Federal University of Rio de Janeiro, Brazil
Session Introduction
Hassan Jalal Aziz
Salahaddin University, Iraq
Title: Evaluation study on The role of physical properties on the efficiency of some antioxidants
Biography:
Hassan Jalal Aziz is lecturer in university of Salahaddin /collage of basic education /general science department. He Attend many conferences outside Iraq, the last was in Leipzig University on 13/10/2015. He published many researches in the field of his specialization in international journals.
Abstract:
This research is interested by comparing the physical properties of three types of petroleum antioxidants. Three types of well-known petroleum antioxidants: Unol, tertiary alkyl primary amine with9 carbon atoms, and tertiary alkyl primary amine with12 carbon atoms were selected to examine their ability as antioxidants for crude diesel fuel. Solubility and boiling point were selected as physical parameter in this research. The study was included the ability of these compounds on their specifications as antioxidants during the oxidation process under elevated temperature. Manometric method was selected to evaluate the oxidation efficiency on the basis of induction period results. The resulted induction periods were 600 sec. , 440 sec. ,212 sec. and 55 sec. for TAPA-12,TAPA-9 ,Unol, and crude diesel respectively.
Biography:
He is from Exploration Department, Sirte Oil Company for Production Manufacturing Oil & Gas, Libya
Abstract:
The study concentrates on characterization and distribution of the Sarir Sandstone reservoir in the Chadar Field. It includes wireline logs analysis integrated with core analysis and analyzed well test data from four wells drilled in the Chadar Field; three wells explored by Mobil Oil Libya in May 1966 and one well by Sirte Oil Company for production, manufacturing of oil & gas in November 2014.The Chadar Field is part of Concession 126; it is located in eastern part of the Sirte Basin in the north central of Libya. The area of study is located in the westward of Messlah High between the south of Ajdabiya Trough and north of Sarir Trough (figure 1). The Chadar Field was first discovered in 1968 and A1-126 well was tested gas condensate flowed to surface from the Sarir Sandstone. The Sarir Sandstone Formation of Upper Jurassic to Lower Cretaceous represents the main hydrocarbon potential reservoir in the Chadar Field. The Sarir Sandstone is distributed widely in the subsurface of the study area and it is composed of a thick sandstone unit interbedded with shale.
Biography:
Behzad Rostami is an Associate Professor of Petroleum Engineering at the Institute of Petroleum Engineering (IPE) at University of Tehran. His research interests include gas injection-based methods for enhanced oil recovery, foam injection and carbonated water injection, CO2 sequestration in saline aquifers and depleted hydrocarbon reservoirs, gravity drainage and multi block interaction in fractured media. He authored more than 40 technical papers in international journals and also supervised more than 30 graduate students.
Abstract:
In wet water media, a continuous thin water film exists on the surface of pores and pore throats in the reservoir rock. As water saturation increases during water flooding, this film coalesces into a water layer, which isolates the residual oil behind the oil bank in the form of more massive ganglia. When the tertiary gas injection process is applied to such a system, direct contact between the oil and gas phases will be impossible due to the presence of the water barrier formed previously. This phenomenon is referred to as water blocking or the water shielding effect. In the current survey, the time required in rupturing the water film shielding the oil as a result of oil swelling caused by the diffusion of dissolved gas in the water phase and trapped oil behind it has been investigated in porous medium at high pressure and temperature. To study the active mechanisms, the experiments have been conducted with two different types of injectants: carbon dioxide and methane (with different solubility in water), under different miscibility conditions at equal reduced pressures. The results show that water film reduces the performance of oil recovery by limiting the interface of oil and gas phase. Under such a condition, the best scenario is the miscible gas injection because the gas can effectively swell the oil and rip the water shield. At miscible and near-miscible conditions, the time required for wiping out the water film increases as the injectant solubility in water decreases; however, there is a negligible difference at the immiscible regime. The trend of oil recovery curves after rupture of the water film shows that oil swelling is one of the main mechanisms involved in water-trapped oil recovery. These results suggest practical guidelines on the effect of water shielding phenomenon in the field of tertiary gas injection. Recent Publications 1. Mirazimi S, Rostami B, Ghazanfari M H and Khosravi M (2017) Water film rupture in blocked oil recovery by gas injection experimental and modeling study. Chemical Engineering Science 161:288???298. 2. Zeinabadi D, Rostami B and Khosravi M (2016) Effect of petro physical matrix properties on bypassed oil recovery from a matrix-fracture system during CO2 near-miscible injection: experimental investigation. International Journal of Multiphase Flow 85:123???131. 3. Kazemi K, Rostami B, Khosravi M and Zeinabadi D (2015) Effect of initial water saturation on bypassed oil recovery during CO2 injection at different miscibility conditions. Energy & Fuels. 29(7):4114???4121. 4. Khostavi M, Rostami B, Emadi M and Roayaie E (2015) Marangoni flow: an unknown mechanism of oil recovery during near-miscible CO2 injection. Journal of Petroleum Science and Engineering 125:263???268. 5. Fatollahi A and Rostami B (2014) Carbonated water injection: effects of silica nano-particles and operating pressure. The Canadian Journal of Chemical Engineering 93(11):1949???1956.
Haifa Tang
Research Institute of Petroleum Exploration and Development, China
Title: Horizontal well for enhanced recovery technology in tight gas based on reservoir structure research
Biography:
Haifa Tang has her expertise in oil and gas production in development geology. Horizontal well is the key technology to develop such tight gas field, and the practice has proven its advantage in improving single well production. But as a whole, whether the horizontal well enhance the recovery efficiency of gas field or not is still a controversy because of the vertical sparse distribution of profit plays. In solving such problem, he presents a new concept of concentration ratio of the vertical profile reserves. And on the basis of this concept, three sand body distribution models have been established. They are single thick block type, multi period vertical overlap pan connected type, and multi period dispersed partially connected type. Reservoir recovery of horizontal well under different sand body combination has been studied, and technical measures to improve the recovery rate of horizontal wells have been proposed
Abstract:
Sulige gas field is the largest tight sandstone gas field in China with low porosity, low permeability, high reservoir heterogeneity, and low single well production, but has huge reserves and high production capacity. Horizontal well is the key technology to develop such tight gas field, and the practice has proven its advantage in improving single well production. But as a whole, whether the horizontal well enhance the recovery efficiency of gas field or not is still a controversy because of the vertical sparse distribution of profit plays. In solving such problem, this paper presents a new concept of concentration ratio of the vertical profile reserves. And on the basis of this concept, three sand body distribution models have been established. They are single thick block type, multi period vertical overlap panconnected type, and multi period dispersed partially connected type. Reservoir recovery of horizontal well under different sand body combination has been studied, and technical measures to improve the recovery rate of horizontal wells have been proposed. The results show that straight wells is not perfect due to the "blocking zone" present in compound sand body of the braided river sedimentary system. The horizontal well can overcome the influence of "blocking zone" to improve the producing degree of reserves within the layer. However, the layered sand body dispersed, horizontal well development will lead to the vertical bearing department of gas reserves is not sufficient, reducing interlayer recovery degree. For the reserves concentration greater than 60%, single period and multi period vertical overlap panconnected type, using horizontal well development can significantly improve the producing degree of reserves and recovery, whose I + II wells are more than 70% proportion. For the multi period disperse partially connected reservoirs with less than 60% concentration of reserves, the development of vertical well pattern and the optimization of the horizontal well location by desserts can improve the recovery by more than 10%. Recent Publications 1. Liu Qunming, Tang Haifa, Lv Zhikai, et al. Well deployment technique for composite subwater distributary channel sand body reservoir architecture of Edong tight gas[J]. Journal of China University of Mining & Technology, 2017,40(5): 1144-1151. 2. Liu Qunming, Tang Haifa, Ji Guang, et al. Characteristics of braided river sedimentary system zones in Sulige gasfield, Ordos Basin [J]. Natural Gas Geoscience, 2016,27(7): 1360-1366. 3. Guo Zhi, Jia Ailin, He Dongbo, Tang Haifa. Control factors on the formation of effective reservoirs in tight sands: Example from Guangan and Sulige Gasfileds[J]. Oil & Gas Geology, 2016,34(1): 78-82. 4. Tang Haifa, Jia Ailin, Peng Shimi, et al. Stochastic modeling of sedimentary microfacies-lithofacies in proluvial fasn reservoir[J]. Journal of China University and Development, 2010, 34(3): 12-17.
Zhikai LV
Research Institute of Petroleum Exploration and Development, China
Title: Production characteristics and productivity evaluation of horizontal wells in sulige tight gas reservoir
Biography:
Zhikai LV has her expertise in oil and gas production in evaluating gas well productivity. According to the one point method, his productivity chart was drawn. With horizontal wells test data, the chart can be used to estimate the absolute open flow rate of horizontal wells to obtain the reference index of reasonable gas production rate quickly and intuitively. Through the analysis of the actual production data of 63 wells which product 3 years, the relationship between the average daily production and absolute open flow rate was regressed. So the initial production rate equation is obtained to determine initial production. The results show that the productivity chart can be used to estimate the absolute open flow rate of horizontal wells to obtain the reference index of reasonable gas production rate quickly and intuitively for Sulige gas field and error range is within 10%.
Abstract:
Horizontal well technology is an effective means to develop tight sandstone gas reservoirs. While horizontal wells development have achieved excellent performance in Sulige gas field, there exists practical problems including difficulty in production characteristics and productivity evaluation. For this, the gas field geology and horizontal well production characteristics were studied firstly. Then, the new method (productivity chart) was established to evaluate the absolute open flow rate of gas well. The time of horizontal well flow to achieve stationary was determined and the well-controlled reserves of the early horizontal wells were calculated by rate transient analysis. Finally, the relationships of reasonable production rate, absolute open flow rate and well-controlled reserves were analyzed. Results showed that initial production of horizontal well is much higher after fracturing, which mainly reflects the gas capacity of well nearby high permeable fractures. However, the subsequent production and pressure are continuously decreased with the extension of production time and generally there is no obvious stable production period. It takes 100 to 600 days for horizontal wells to enter the boundary controlled flow period due to poor properties and strong heterogeneity of Sulige tight gas field. Horizontal well production decline is depleted, early decline is dramatic and late decline is gradually slow. The relationship of reasonable horizontal well production and absolute open flow rate is power function. Reasonable production proration is gradually decreases with the increase of absolute open flow. The relationship of reasonable horizontal well production and well-controlled reserves is linear relation. This result is consistent with the actual production of data, which is benefit for production proration determination of fractured horizontal wells and production capacity building of tight gas reservoirs. Recent Publications 1. Qunming LIU, Haifa TANG and Zhikai LV, et al. (2017) Well deployment technique for composite subwater distributary channel sand body reservoir architecture of Edong tight gas. Journal of China University of Mining & Technology; 855-876. 2. Bo LI, Ailin JIA, Dongbo HE and Zhikai LV, et al. (2015) Productivity evaluation of horizontal wells in Sulige tight gas reservoir with strong heterogeneity. Natural Gas Geoscience; 2325-2334. 3. Ailin Jia, Zhikai Lv. (2014) Dynamic Effect of Capillary Pressure in Tight Gas Reservoir. The Open Petroleum Engineering Journal: 71-79. 4. Zhikai Lv, et al. (2014) The Effect of Gas Slippage on Laboratory Results and Gas Well Production. Theory and practice of natural gas development Petroleum Industry Press: 200-206. 5. Zhikai LV, et al (2013). Factors Affecting the Productivity of a Multi-fractured Horizontal Well. Petroleum Science and Technology: 2325-2334.
Zunyi Xia
Peking University, China
Title: Micro-nano pore structure and connectivity investigation in continental shale Zhanhua Sag, China
Biography:
Zunyi Xia is currently a research associate in College of Engineering, Peking University. China. She earned her second MS degree from the University of Oklahoma, Oklahoma, US. She earned her PhD from Peking University, Beijing, China. She has worked on shale reservoir characteristic since 2006. Her research interests include rock physics, unconventional reservoirs and reservoir characterization.
Abstract:
Pore structure and connectivity controls the fluid flow in the porous media. Shale micro-nano pore structure and connectivity in the continental Es31 Formation in the Zhanhua Sag is evaluated with FIB-SEM, High resolution CT, CO2 adsorption, N2 adsorption, and merury-injection porosimetry methods. The present study shows that micropores, mesopores ,macropores and micro-cracks are developed in the shale. The structure of the pore are mainly parallel plate, groove, slit, and ink-bottle type pore. Macropores have a greater capacity of providing pore volume rather than micropores and mesopores. Micropores are dominant in surface area. There is a positive correlation between Micropores volume and TOC, Clay mineral content. There is a positive correlation between Mesopores and clay mineral content. Pore connectivity of the continental shale nano pores are mainly organic pore, which are developed better with higher maturity. Recent Publications 1. Lei Wang, Zhenzhen Dong, Xiang Li , Zunyi Xia. A multi-scale flow model for production performance analysis in shale gas reservoirs with fractal geometry. Scientific Reports, revised submitted (2018). SCI IF=4.259. 2. Lei Wang, Xiaoxia Chen, Zunyi Xia. A Novel Semi-Analytical Model for Multi-branched Fractures in Naturally Fractured- Vuggy Reservoirs. Accepted. 2018. Scientific reports. 3. Lei Wang, Cheng Dai, Xiang Li , Zunyi Xia, Cai Wang. Pressure transient analysis for asymmetrically fractured wells in hydrocarbon reservoirs with dual-permeability behavior. Accepted. 2018. International Journal of Hydrogen Energy. 4. Zunyi Xia, Carl Sondergeld, Chander Rai. Rock Mechanics of Shale. Abstract is accepted by AAPG, 2008. 5. Late Jurassic and Early Cretaceous the Bivalve Buchia fauna of Himalaya Region, South Tibet, Xia, Zunyi, Bai, Zhiqiang (Acta Palaeontologica Sinica. 44(4), 2005). 6. Xia, Zunyi, Bai, Zhiqiang. Discussion on a CO2 geological sequestration by methanogens in the biogenic gas field in China. (Petroleum Exploration and Development, Vol. 31, No. 6, 2004).
Fawzi S. F. Hamad
Sirte Oil Company, Libya
Title: Waha Reservoir Characterization and distribution in the Ralah Field, Concession 6, Sirte Basin, Libya
Biography:
He is from Sirte Oil Company for Production Manufacturing Oil & Gas, Exploration Department
Abstract:
The Ralah Field is one of the concession 6 fields operated by Sirte Oil Company. It is located in the southern part of the Sirte Basin (Libya), approximately 200 km south of the Mediterranean Sea. Geographically it is located between latitude 28� 42' 12" and 28� 51' 40" North and longitude 19� 51' 58" and 19� 59' 57" East. The Upper Cretaceous Waha Formation is the main producer in the Ralah Field. The Waha reservoir ranges from zero thickness on the crests of the paleo-topographic highs to over 45 m on their flanks. The Ralah Field was discovered in June 1964 with the drilling of DD1-6 well through the Waha Formation and proved to be the most prolific reservoir in the area. Oil flowed on a drill stem test in the discovery well. 2D seismic surveys were done in the Ralah Field. In 2004 a 3D seismic survey of 340 km�, which covered all the Ralah field area was completed to evaluate remaining and upside potential. The seismic interpretation has acquired new drillable well locations. Seismic and well data of nineteen wells have been used in this project. Waha reservoir was evaluated, analyzed and interpreted. Seismic interpretation and coherence attribute analysis were performed for the fault trend identification; and Property models were constructed in terms of clay volume, porosity, permeability and hydrocarbon saturation. The study concluded to show that; all of the faults in the Ralah Field are normal extension with modest throws and trending in NW-SE direction; Waha Reservoir is divided into four main facies (Wackestone, Rudstone, Dolomite Cemented Sandstone and Bioclastic Sandstone). Some of these facies are considered to be a tight non-productive facies (tight zone), and others have good reservoir properties (PHIE=13-25% & K=1-30mD).