DE2927222A1 - Geothermal heat recovery system - pumps water down inside borehole casing and up through inner tube after heating - Google Patents

Abstract

The borehole and connection system utilises the heat of the earth for heating, hot-water supply and industrial purposes. The borehole has an outer casing and an insulated inner tube. Prepared water is forced downwards inside the outer casing, and rises heated to the surface again in the inner tube. From there it is passed through heat-exchangers and back, still hot, down inside the casing again. Since the prepared water does not come into contact with the earth itself, there is no contamination, and only minimum evaporation loss.

Description

Circuit diagram and borehole equipment for the use of geothermal energy for Heating, water heating and industrial purposes.

Description: Boreholes need to be drilled. The piping the boreholes must be made in such a way that treated water is pumped down the outer pipe is heated and in the middle (inner tube) rises to the surface of the earth (Fig. 1).

In order to largely eliminate heat loss, the Inner tube required. Repeated pumping would also increase the carrier temperature raise.

Several holes drilled - offset in depth by one to achieve optimal utilization of geothermal energy - can be connected to a collector will. From there, the heat transfer medium is passed on via a distributor for a wide variety of purposes such as district heating and hot water supply in Metropolitan areas, etc. (Fig. 2).

Since the temperature gradient is very low, great drilling depths are required (technically possible because in the states of Texas and Oklahoma, USA, bores have already been made up to the 8,000 m limit).

Test drillings that have already been carried out in Germany provide information over rock formations, so problem bores are ruled out.

Metropolitan areas are known, heat requirements can be determined in advance.

LEGEND ! Water treatment (fresh water first filling, lost water) 1.1 Water tank for treated water and condensate 2 Condenser for D-turbine 2.1 Condenser for industrial purposes 3 steam turbine Pm8x 10 bar, 185 K 4 three-phase generator for electric motors of the pumps 5 storage tanks with water and steam collector 5. 1 steam collector 6 - - Pressurized water centrifugal pump geothermal energy 6.1 Centrifugal pump for treated water and condensate 7 Control panel for pump drive and external power feed in start-up operation 7.1 External power supply 8 Feed water distributor -9 Return water distributor 10 - Borehole tightly cased, insulated on the inside 10.1 to 10.6 Boreholes 11 Temperature controller for circuit water 12 Pressure regulator for return 12.1 Pressure regulator for industrial steam 13 - Heat exchanger for consumers - (hot water heating, domestic water) 14 Water consumption ar Return 15 heat consumers with heating surface, condensing steam.

Claims (1)

Patent claims: Generic term: circuit diagram and borehole equipment to use geothermal energy for heating, water heating and industrial purposes. Characteristic part: borehole and piping consisting of an outer jacket and insulated inner tube. Treated water is pressed down in the outer tube and occurs heated in the inner tube back to the surface of the earth, from where it goes to the circuit diagram (Fig. 2) marked heat exchangers is passed on to afterwards in the circuit warmed up - to be pushed down again. Through this method, the treated water comes with the soil not in contact, which means that no contamination of the water occurs and only very minimal water losses occur, e.g. through evaporation. Preamble of the dependent claim: Piping - double pipe with heat exchange. Water treated, heated, conveyed without loss of water. Characteristic part of the dependent claim: treated water comes not in contact with the ground. - -