US 4,448,237 A · System for efficiently exchanging heat with ground water in an aquifer

Abstract

A method and means for using ground water in an aquifer as a heat source and heat sink are disclosed wherein heat is exchanged between the uniform temperature ground water and heat-exchanging apparatus at the earth's surface through a single well bore. The ground water is exchanged between an upper and lower portion of the aquifer, alternatively depending on the operating mode, in such a manner that a stratified lateral flow of the water after heat exchange is produced following natural convective paths in the top or bottom of the aquifer and resulting in wide laminar dissipation of the altered temperature water while avoiding thermal mixing between that water and the remaining uniform temperature water in the aquifer. This manner of exchange provides a continuous flow of heating or cooling water at or near the ambient aquifer temperature without any depletion of the aquifer. Embodiments are described wherein the aquifer water is brought to the earth's surface and wherein a separate heat-exchanging fluid is circulated between the aquifer and the earth's surface, and modifications are also disclosed involving a valved plenum device for use with the former embodiments and whereby the aquifer may be used to store solar heat.

Claims21

Dependent claims

A method of using ground water in an aquifer as a heat source and heat sink comprising the steps of:

sinking a well bore into an aquifer through an upper portion and into a lower portion in said aquifer, and in which aquifer the ground water is normally at a substantially uniform temperature;
producing a flow of the ground water between said upper and lower portions of said aquifer through a defined path beginning and ending in said well bore;
exchanging heat with said flowing ground water at a defined region along said flow path;
and
producing a flow of ground water through said flow path such that water from which heat is to be extracted and water which has absorbed heat in the defined region is respectively withdrawn from and returned to said upper aquifer portion, and water which is to absorb heat and water from which heat has been extracted in said defined region is respectively withdrawn from and returned to said lower aquifer portion.

2 more elements

A system for using ground water in an aquifer as a heat source and a heat sink comprising:

a well bore extending into an aquifer through an upper portion and into a lower portion in said aquifer;
water-conducting means for conducting ground water from and returning it to said well bore comprising:
conduit means extending into said well bore to the level of said lower aquifer portion for withdrawing ground water from and returning it to both said lower aquifer portion and said upper aquifer portion;
heat-exchanger means for exchanging heat with the aquifer water passing through said water-conducting means;
and
means for producing water flow from said aquifer through said water-conducting means such that water from which heat is to be extracted and water which has absorbed heat is respectively withdrawn from and returned to said upper aquifer portion;
and water which is to absorb heat and water from which heat has been extracted is respectively withdrawn from and returned to said lower aquifer portion;
and wherein said conduit means comprises:
supply line means for withdrawing water through said well bore from said aquifer and conducting said withdrawn water to said heat-exchanger means, and return line means for returning water, which has been conducted from said aquifer to said heat-exchanger means, from said heat-exchanger means to said aquifer within said well bore, and wherein said supply line means comprises:
means for defining a chamber disposed in said well bore between the levels of said upper and lower portions of said aquifer;
valve means for selectively admitting water from either said upper portion of said aquifer into said chamber or from said lower portion of said aquifer into said chamber;
and
means for conducting said admitted water to said heat exchanger means.

10 more elements

A system for using ground water in an aquifer as a heat source and a heat sink comprising:

a well bore extending into an aquifer through an upper portion and into a lower portion in said aquifer;
water-conducting means for conducting ground water from and returning it to said well bore comprising:
conduit means extending into said well bore to the level of said lower aquifer portion for withdrawing ground water from and returning it to both said lower aquifer portion and said upper aquifer portion;
heat-exchanger means for exchanging heat with the aquifer water passing through said water-conducting means;
and
means for producing water flow from said aquifer through said water-conducting means such that water from which heat is to be extracted and water which has absorbed heat is respectively withdrawn from and returned to said upper aquifer portion;
and water which is to absorb heat and water from which heat has been extracted is respectively withdrawn from and returned to said lower aquifer portion;
and wherein said conduit means comprises:
supply line means for withdrawing water through said well bore from said aquifer and conducting said withdrawn water to said heat-exchanger means, and return line means for returning water, which has been conducted from said aquifer to said heat-exchanger means, from said heat-exchanger means to said aquifer within said well bore;
and said supply line means comprises a pipe having a threaded lower end;
and chamber defining means disposed in said well bore between the levels of said upper and lower portions of said aquifer with an upper wall having a threaded opening therein for accomodating a portion of the threaded lower end of said pipe;
and wherein said water flow producing means comprises submersible pump means for pumping aquifer water through said supply line means;
and
further comprising means for attaching said submersible pump means to said threaded lower end of said pipe.

11 more elements

A system for using ground water in an aquifer as a heat source and a heat sink comprising:

a well bore extending into an aquifer through an upper portion and into a lower portion in said aquifer;
water-conducting means for conducting ground water from and returning it to said well bore comprising:
conduit means extending into said well bore to the level of said lower aquifer portion for withdrawing ground water from and returning it to both said lower aquifer portion and said upper aquifer portion;
heat-exchanger means for exchanging heat with the aquifer water passing through said water-conducting means;
and
means for producing water flow from said aquifer through said water-conducting means such that water from which heat is to be extracted and water which has absorbed heat is respectively withdrawn from and returned to said upper aquifer portion;
and water which is to absorb heat and water from which heat has been extracted is respectively withdrawn from and returned to said lower aquifer portion;
and wherein said conduit means comprises a first pipe extending into said well bore to the level of said upper aquifer portion and a second pipe extending into said well bore to the level of said lower aquifer portion;
and said water flow producing means comprises:
a first pump-turbine means connected to said first pipe for withdrawing water through said well bore from said upper aquifer portion and supplying it to said heat exchanger means and for withdrawing energy from water returned to said upper aquifer portion from said heat exchanger means;
and
a second pump-turbine means connected to said second pipe for withdrawing water through said well bore from said lower aquifer portion and supplying it to said heat exchanger means and for withdrawing energy from water returned to said lower aquifer portion from said heat exchanger means.

9 more elements

Dependencies are inferred from the claim text.

System for efficiently exchanging heat with ground water in an aquifer

Life of this patent

System for efficiently exchanging heat with ground water in an aquifer

Life of this patent

Abstract

Claims21