نوع مقاله : مقاله پژوهشی
نویسندگان
1 کارشناسی ارشد، دانشکده مهندسی نفت، دانشگاه صنعتی امیرکبیر
2 دانشیار، دانشکده مهندسی نفت، دانشگاه صنعتی امیرکبیر
3 استادیار، دانشکده مهندسی نفت، دانشگاه صنعتی امیرکبیر
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
As the most significant factor determining the final success of a hydraulic fracturing operation, fracture conductivity is influenced by proppant operating variables including mesh size, proppant concentration, and crushing behavior under minimum horizontal stress. Outcrop samples of the Ilam Formation were cut and prepared in the desired dimensions to simulate fracture in one of the Iranian reservoirs. As natural proppants, two groups of silica sand were collected from Firozkoh and Hamadan mines. Three mesh sizes were used to screen the proppants: 16/30, 20/40, and 30/50. In conductivity tests, Firozkoh proppants were used at two concentrations of 2 and 0.5 pounds per square foot. Experiments were carried out with a conductivity measuring apparatus by injecting nitrogen gas into the conductivity cell at different flow rates. This was done to simulate gas flow through fracture media. As a final step, the crushed percentage of proppants was determined and Forchheimer's equation was used to calculate conductivity values. As determined by the study, a significant decrease in conductivity values was observed with increasing closure stress. Firouzkoh 20/40 displayed better conductivity than Hamedan 20/40 proppant and performed better under the same stress conditions. Higher values of sphericity and roundness explain this. A comparison of the conductivity of 16/30, 20/40, and 30/50 proppants from Firuzkoh sand revealed that the 30/50 proppant had the lowest conductivity reduction compared to the other two samples up to a stress of 7251 psi because there are more contact points between the particles, the stress distribution is better between the particles, and the proppants do not crush as easily. A comparison of two amounts of Firouzkoh 20/40 proppant showed that more particles formed in the fracture as the proppant concentration increased. Consequently, the crushed percentage was reduced and conductivity values were maintained at higher proppant concentrations.
کلیدواژه‌ها [English]
1 .Economides, M.J. and K.G. Nolte, Reservoir stimulation. Vol. 2. 1989: Prentice Hall Englewood Cliffs, NJ.
2 .Elsarawy, A.M. and H.A. Nasr-El-Din, A new method to measure propped fracture width and proppant porosity in shale fractures. Journal of Petroleum Science and Engineering, 2019. 181: p. 106162.
3 .Hafidh, H., OPEC Annual Statistical Bulletin 2016. Organization of the Petroleum Exporting Countries, 2016.
4 .Hill, A.D., et al. Small-scale fracture conductivity created by modern acid fracture fluids. in SPE Hydraulic Fracturing Technology Conference. 2007. OnePetro.
5 .Simo, H., M. Pournik, and C. Sondergeld. Proppant Crush Test: A New Approach. in SPE Production and Operations Symposium. 2013. OnePetro.
6 .Department, A.P.I.P., Recommended practices for evaluating short term proppant pack conductivity. Vol. 61. 1989: American Petroleum Institute.
7 .Kothamasu, R., Y.K. Choudhary, and M.K. Kurubaran. Comparative study of different sand samples and potential for hydraulic-fracturing applications. in SPE Oil and Gas India Conference and Exhibition. 2012. OnePetro.
8 .Zhao, L., et al., Experimental Study on a new type of self-propping fracturing technology. Energy, 2019. 183: p. 249-261.
9 .Beg, M.S., et al., A systematic experimental study of acid fracture conductivity. SPE Production & Facilities, 1998. 13(04): p. 267-271.
10 .Walsh, J. Effect of pore pressure and confining pressure on fracture permeability. in International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts. 1981. Elsevier.
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