A Cellulose Fracturing Fluid with Instant Solution and No Residue

Abstract Tight reservoirs normally have production problems due to very low matrix permeability and different damage mechanisms during drilling, completion and stimulation operations. These reservoirs have small pore throat size with significant capillary pressure energy suction that imbibes and holds liquid in the capillary pores. Such residues from Guar after gel breaks cause formation damage and low conductivity, and it can significantly reduce well productivity even in tight gas reservoirs. This paper presents a new cellulose derivative of instant dissolution and free of residue. The field test results of the new fluid in tight gas reservoirs in China show importance of minimizing formation damage in a hydraulic fracturing stimulation. Otherwise, the well productivity improvement may not be achieved in the case of excessive residues into formation during hydraulic fracturing operations. A new fluid has been applied in 18 wells in western China and the results show that the new fluid was easy to prepare and rapidly dissolved with no "fish eye", this system can reach 97% of the peak viscosity within 2 minutes, and the surface tension of the gel breaking liquid is 18.44 mN/m. No residue was found after the gel was broken, its conductivity was improved, and the formation damage is less than 13% in the core test. Meanwhile it has excellent properties of proppant suspension. Gas production in multiple wells of the tight gas reservoir increased to 2.13×105 m3/d after stimulation with the new fluid, 4.2 times higher than similar groups of wells using Guar-based fracturing fluids.