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  • Coiled Tubing Technology: Acid tunneling with coiled tubing significantly increases production

    V. Espina, M. Guerrero, O. Colmenares, J. Diaz, P. Rae and G. Di Lullo

    Carbonate formations form about 35% of the world’s petroleum reservoirs, yet these same reservoirs contain an estimated 60 to 70% of the world’s traditional reserves. They are found in most oil producing provinces, but are particularly common in the Middle East, Central Asia, the United States, Canada and Northern Europe. Important carbonate reservoirs are also found in Sumatra, Borneo, China, Brazil, Venezuela and elsewhere. Like sandstones, carbonate reservoirs can be drilled and completed using conventional techniques. However, drillers often overlook a combination of interesting properties of carbonate rocks: their mechanical integrity and their high solubility in acid. Typical carbonate solubility in hydrochloric acid is greater than 95% and can often exceed 99.5%. This characteristic lends itself to some novel techniques for constructing drainage holes in such formations. Using a suitable nozzle to jet acid with coiled tubing.

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2013 Fracturing Technology

2013 Fracturing Technology