Nanosilica dispersion lost circulation material (LCM)

Abstract

A lost circulation material (LCM) is provided having an acidic nanosilica dispersion. The nanosilica dispersion of the LCM may form a gelled solid after interaction with a formation over a period. Methods of lost circulation control using LCMs are also provided.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority from U.S. Provisional Application No. 62 / 454,253 filed Feb. 3, 2017, and titled “NANOSILICA DISPERSION LOST CIRCULATION MATERIAL (LCM) AND WELL TREATMENT FLUID.” For purposes of United States patent practice, this application incorporates the contents of the Provisional Application by reference in its entirety.BACKGROUNDField of the Disclosure[0002]The present disclosure generally relates to controlling lost circulation in a well during drilling with a drilling fluid and reducing water production during production from the well. More specifically, embodiments of the disclosure relate to lost circulation materials (LCMs) and well treatment fluids.Description of the Related Art[0003]Various challenges are encountered during drilling and production operations of oil and gas wells. For example, fluids used in drilling, completion, or servicing of a wellbore can be lost to the subterranean formation while circu...

AI Technical Summary

Benefits of technology

This patent describes a method for controlling the flow of fluids in a subterranean formation during oil production. The method involves using a lost circulation material (LCM) made of an acidic nanosilica dispersion. The LCM is introduced into the wellbore to reduce the rate of lost circulation, which refers to the loss of fluid from the wellbore during production. By decreasing the permeability of the formation, the method increases the yield of hydrocarbons from the formation. The LCM forms a gelled solid when in contact with the formation, which helps to mitigate lost circulation. The patent also describes the use of polyester fibers, polypropylene fibers, starch fibers, polyketone fibers, ceramic fibers, glass fibers, and nylon fibers as additives to enhance the effectiveness of the LCM. Overall, the patent provides a solution for enhancing oil production and reducing water production costs.

Problems solved by technology

Various challenges are encountered during drilling and production operations of oil and gas wells.

For example, fluids used in drilling, completion, or servicing of a wellbore can be lost to the subterranean formation while circulating the fluids in the wellbore.

As a result, the service provided by such fluid is more difficult or costly to achieve.

Such lost circulation can be encountered during any stage of operations and occurs when drilling fluid (or drilling mud) pumped into a well returns partially or does not return to the surface.

While de minimis fluid loss is expected, excessive fluid loss is not desirable from a safety, an economical, or an environmental point of view.

Lost circulation is associated with problems with well control, borehole instability, pipe sticking, unsuccessful production tests, poor hydrocarbon production after well completion, and formation damage due to plugging of pores and pore throats by mud particles.

Lost circulation problems may also contribute to non-productive time (NPT) for a drilling operation.

In extreme cases, lost circulation problems may force abandonment of a well.

In another example, after a well is completed and becomes a producing well, water production from the well may cause significant economic drawbacks.

High water production rates may cause a reduction in well productivity, an increase operating expenditures, and can completely block production from wells.

Such water production is typically produced at the expense of oil or gas recovery, and, in severe cases, the water influx may be so great that oil or gas production is choked off completely.

The costs incurred in lost circulation situations may be due to lost time, losses of drilling fluids, and losses of production.

Existing LCMs may perform poorly in mitigation and prevention of moderate lost circulation and seepage type lost circulation, and may not be suitable for controlling severe loss of circulation.

Costs incurred in loss circulation situations may be due to losses of drilling fluids, losses of production, and the costs of LCMs.

This uneven flow of the aqueous displacement fluid through the formation reduces the overall yield of hydrocarbons from the formation.

However, existing techniques may be unstable at high temperatures or in the presence of certain chemicals (for example, acids and brines), resulting in decomposition or degradation and reducing or eliminating their effectiveness.

Moreover, some polymers used for controlling water production may be environmentally damaging.

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