Weighted slickwater fracturing fluid and preparation method thereof

Abstract

The invention relates to a weighted slick water fracturing fluid and a preparation method thereof, and belongs to the technical field of oil and gas field fracturing. The weighted slick water fracturing fluid is prepared from a JHFR drag reducer, a JHFD multifunctional additive, an HE-BIO biological oil displacement agent and a weighting agent according to a certain mass percent. The density of the weighted slick water fracturing fluid is adjustable in the range of 1.17-2.10 g / cm3, various adaptive weighting agents are adopted, and the drag reduction rate reaches 66% under the condition of a 30% calcium chloride weighting agent, besides, the surface tension is as low as 23.4 mN / m, the interfacial tension is between 10<-2> mN / m and 10<-3> mN / m, and the anti-swelling rate is greater than 80%. By means of the product, the requirements of fracturing construction on low friction resistance, shale hydration inhibition, low reservoir damage and rapid flowback are met, the requirements on construction equipment and tools are effectively reduced, and the fracturing fluid is safe to use, simple to prepare, low in cost, wide in application range and good in pump pressure reduction effect. The invention can solve the problems that the existing guanidine gum weighted fracturing fluid is high in residue content after gum breaking, high in friction resistance, low in flowback rate, high in clean fracturing fluid consumption, high in cost, poor in salt resistance, low in reachable density, poor in provided shaft liquid column pressure and large in application limitation.

Description

technical field [0001] The invention relates to a weighted slick water fracturing fluid and a preparation method thereof, belonging to the technical field of oil and gas field fracturing. Background technique [0002] When fracturing technology is applied to special oil and gas wells such as high-pressure wells, deep wells, ultra-deep wells, and tight oil and gas wells, a major problem is that the construction pump pressure is too high, so very high requirements are placed on fracturing construction equipment and tools , greatly increased the construction risk; at present, using aggravated fracturing fluid and increasing the pressure of the liquid column are the main methods to reduce the pump pressure of fracturing construction; Most of these weighted fracturing fluids are guar gum weighted fracturing fluids or clean fracturing fluids. By adding weighting agents such as sodium nitrate and potassium formate, the liquid column pressure of the wellbore is increased to reduce w...

AI Technical Summary

Problems solved by technology

However, in the actual construction process, due to the problems that guar gum itself is not easy to dissolve, the residue content after breaking the gel is large, the friction resistance is high and the flowback rate is low.

After adding the weighting agent, the salt will not only compete with the guar gum for water molecules, increase the dissolution time of the guar gum, but also increase the frictional resistance of the fracturing fluid and the difficulty of breaking the fracturing fluid, resulting in poor pump pressure reduction effect

During the construction of a well with a depth of 7600m, the pump injection density is 1.35 g / cm 3 Potassium formate aggravated fracturing fluid, its oil pressure is almost the same as that of non-aggravated fracturing fluid, and the purpose of reducing pump pressure cannot be achieved

Although clean fracturing fluid has the advantages of simple preparation, low friction, no residue, little damage to the formation, fast flowback speed after construction, and high flowback rate, it has a large amount of consumption, high cost, and poor salt resistance. , the wellbore fluid column pressure provided is not good, and the application limitations are large

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