Method of cooling downhole element using nanoenhanced downhole fluid

1. A method of drilling a borehole, comprising:

contacting

a downhole fluid comprising

a clay,

a fluid medium,

an additive, and

a nanoparticle, the nanoparticle being uniformly dispersed in the downhole fluid; to

a downhole element in a downhole environment before, during, or after drilling,

wherein the downhole fluid absorbs heat generated by the downhole element during drilling.

2. A method of transferring heat to or from a downhole element, the method comprising:

contacting a downhole fluid comprising:

a fluid medium which comprises an aqueous fluid; a gas; an ionic liquid; an emulsified mixture of one or more of water, brine, oil, and air; or a combination comprising at least one of the foregoing; and

a nanoparticle, the nanoparticle being uniformly dispersed in the downhole fluid,

to a downhole element inserted in a downhole environment,

wherein the nanoparticle is derivatized to include a functional group, is underivatized, or includes a combination of derivatized and underivatized nanoparticles, and the functional group comprises carboxy, epoxy, ether, ketone, amine, hydroxy, alkoxy, alkyl, aryl, aralkyl, alkaryl, lactone, functionalized polymeric or oligomeric groups, ionic groups, or a combination comprising at least one of the forgoing functional groups.

3. The method of claim 2 , wherein the downhole fluid further comprises:

a nanoparticle which is not derivatized; and

a dispersant.

4. The method of claim 3 , wherein the dispersant is ionic or non-ionic, and is a fatty acid or derivative thereof, a poly(alkylene oxide), a polysiloxane, a polymeric surfactant, an organic-inorganic medium, or a combination comprising at least one of the foregoing.

5. The method of claim 2 , wherein the downhole fluid further comprises

a thixotropic clay, and

an additive.

6. The method of claim 5 , wherein the thixotropic clay is bentonite, montmorillonite, kaolinite, or a combination comprising at least one of the foregoing.

7. The method of claim 5 , wherein the additive comprises an antioxidant, a mineral additive, a salt, a polymer, a surfactant, a shear thinner, a circulation control additive, an acid, a base, a hydroxy-containing organic compound, a viscosifying agent, or a combination comprising at least one of the foregoing.

8. The method of claim 5 , wherein the additive is barium sulfate, calcium carbonate, hematite, xanthan gum, guar gum, starch, cellulose, alcohols, glycols, polyols, amines, fatty acid esters, purified paraffin, isomerized olefin, or a combination comprising at least one of the foregoing.

9. The method of claim 2 , wherein contacting further comprises:

injecting the downhole fluid down a well pipe,

circulating the downhole fluid on and around the downhole element,

returning the downhole fluid to a surface heat exchanger via an annular space surrounding the well pipe, and

cooling the downhole fluid by passing the downhole fluid through the surface heat exchanger.

10. The method of claim 9 , wherein the downhole fluid is injected down the drill pipe after cooling, and partially cools the downhole fluid returning to the surface via the annular space through indirect contact through the drill pipe.

11. The method of claim 2 , further comprising treating the downhole fluid to remove solid residues after returning.