Low Concentrations Of Guar Gum Fracturing Fluid Used In The Fracturing

In recent years, the increasing production and production technology of compact low permeability, special low permeability reservoir and deep volcanic reservoir has put forward more and more strict requirements to fracturing technology. Fracturing fluid is an important part and key link to fracturing modification, if it constructed successfully or not is decided by the merits of its performance and effectiveness of the quality of fracturing fluid. As for the vulnerable reservoir, deep and high temperature reservoir, this effect is more prominent. High temperature, low damage, low cost is the main direction of development of the fracturing fluid.In this paper, on the basis of reservoir indoor experimental evaluation, which includes whole-rock analysis, mercury analysis, reservoir rock mechanics analysis etching reaction analysis, sensitive experiments and so on. We further researched the performance evaluation and selection of fracturing fluid components. By the method of experimental study, we researched the ultra-low concentration of hydroxypropyl guar gum fracturing fluid system, and analyzed configuration fracturing fluid influencing factors, evaluated the fracturing fluid form cross-linking properties, the viscoelasticity and sand carrying properties, gel breaking performance, residue content and injury. We got the following conclusions: 1: Hydroxypropyl guar gum fracturing fluid 110℃ flow curve, its frozen adhesive decreased in the process of heating, and remained the same after the temperature stability, this can indicate that the molecular chains break did not last. 2: The sand carrying ability of low concentration guar gum fracturing fluid comes mainly from its elastic properties, not like ordinary guar gum fracturing fluid which sand carrying ability mainly from viscous properties. 3: The optimization of the breaker dosage can realize gel breaking completely, the breaking liquid viscosity <3mPa.s, it reduced the damage of adhesive residue to the fracture and reservoir. 4: Fracturing fluid has a lower table- interfacial tension, higher contact angle, it can help to reduce the capillary force, flow back after fracturing construction.Erlian exploration area innovatively used the new type of super-low concentration system in 2012. It applied multiple cross-linker, reduced the amount of guar gum and kept the ability of cross-linking and sand-carrying. Then, it reduced the cost and the residue of reservoir damage. This meet the requirements of large-scale measurement innovation. The relative concentration of thickener reduced by 35-45%, residue reduced by 38-53%, core loss ratio is 7.59%. Erlian exploration area applied 5 layers of 3 wells, the previous 0.48% of guar gum concentration is reduced to 0.2%-0.35%, sand ratio is 15%-28% to meet the technical requirements, while reduced operating cost. The cost of guar gum reduced 543,400 yuan for only five wells, to achieve the transformation of the reservoir efficient low-cost, low-residue, low damage.