00011341 Liquid CO2 Fracturing.pdf

SPE SPE 11341 Sand Fracturing With Liquid Carbon Dioxide by Allen T. Lillies, Canadian Fracn?asterLtd.,and Steven R. King, * American %crnaster /nc. ‘Member SPE-AIME Copyright 1982 Society of Petroleum Engineers of AlME This paper was presented al the 19e2 ProductionTechnology Symposium. held in Hobbs, New Mexico, November 6-9, 1982. The malerial is subjecl to correctionby !he aulhor. Permission to copy is restricted\o an abstract of not more than 300 words. Wrile 106200 N. Central Expressway, Drawer 84706, Dallas. TX 75206. ABSTRACT C(J2 ia very soluble in crude oi1 and sllghtly soluble in water. co~ The for aids quest cleaner fracturing fluids has led to the development of sand recovery in oil bearing formations aa it is miscible with most crudes and fracturing greatly using liquid carbon dioxide reduces oil viscosity. co~ dissolved in (co*) as the proppant carrier fluid. water will form weak carbonic acid which has C02 is handled at the surface as a liquid a pH of 3. There is no indication that at approximately200 psi and -30”F. Special C02 or the resultant carbonic blending equipment has been developed to acid doea any formation damage in sandstone inject proppant directly into the liquid reservoirs. CO at these surface conditions. la~en liquid C02 is then pum~~daa~~ C02 has been used since early in the conventional equipment. At stabilized 1960’s in fracture stimulation of oil and reservoir temperature and pressure, the gas wells. The C02 was pumped with the liquid 302 vaporizes in a gas wall or oil or water baaed treating fluid in ratios vaporizes and is partially dissolved -in the - sufficient“togas lift the liquid back to”” reservoir oil in an oil well. The greateat the surface after the treatmsnt. Further potential of liquid C02 fracturing is the development led to higher CO ratios where elimination of most of the formation damage the liquid C02 was ?effectivey part of the normally associated with fracturing fluids fracture generating liquid (50%) with the