A New Thickener for CO₂ Anhydrous Fracturing Fluid

¹ Huaneng Clean Energy Research Institute, Chian
² China University of Petroleum-Beijing, Chian
³ Huaneng International Power Development Corporation, Chian
⁴ Beijing Oil and Gas Pipeline Control Center, Chian

^a Corresponding author: zhangjian@hnceri.com

Abstract

CO₂ dry fracturing technology is well-known for its advantages. Little water is used in this technology, which is able to ease the pressure of consumption on water resources. Many abroad theoretical researches, laboratory experiments and field tests have been taken to explore the yield mechanism, the adaptability and the technology of pure liquid CO₂ fracturing. These achievements have been applied to a variety of reservoirs transformation and improven the effectiveness of stimulation treatment in a degree. The researches and studies in the domestic didn’t get popular until recent years. Thus, this article firstly introduces the main development and application about pure CO₂ anhydrous fracturing technology, and sums up the effect and evaluation of its fluid through application examples both in the domestic and abroad. However, although this technology has many excellent qualities, but systematic studies indicate that its proppant-carrying capacity is less competitive because of the low viscosity of pure CO₂ liquid and other reasons. In a consequence, it is necessary to develop an appropriate thickener for CO₂ anhydrous fracturing fluid to improve its carrying capacity. Then this article describes some studies of previous scholars about CO₂ thickener. Then we put forward our own research ideas and transform it into actual experiments. Thanks to the valid performances of these tests, we successfully develop a thickener X and cosolvent B.