skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Flowing geothermal wells and heat recovery systems

Patent ·
OSTI ID:6536917

The flow performance of the geothermal wells represents the ability of the wells to produce useful heat. A liquid-dominated geothermal well can be made to flow by introducing a primary fluid at a selected level in the well. In the process disclosed herein, a primary fluid is introduced into the well casing through a plurality of valves at preselected elevations to accomplish the startup of the flow from the well, the continuous or intermittent, uninterrupted production of brine, and a regulated shutdown. In normal flowing operation, upon injection of the primary fluid through the valves into the well casing, the primary fluid vapor, together with geothermal steam will lift the brine from the depths of the well to the surface of the earth, where the geothermal heat stored in the brine and in the vapors that are co-produced with the brine can be further utilized. The process disclosed herein also minimizes the formation of scale in the well casing. Scale in the geothermal well casing may be formed by precipitation of minerals due to the reduction of geothermal brine temperature and/or geothermal brine flashing due to reduced pressure. By injecting vaporized primary fluid into the geothermal well, the flow from the well can be stimulated with little or no temperature drop in geothermal brine in the well casing. Thus, with the proper back pressure at the geothermal well head, precipitation of solids in the well casing can be controlled. In some cases, the startup of geothermal wells is difficult because the wells do not self-flow with internal flashing. To start up such wells, where the internal temperature of the brine is hot enough for internal flashing, yet self-starting of the well is difficult, the process disclosed herein utilizes a steaminjection system to introduce live steam into the geothermal water at preselected elevations in order to heat up the well water and initiate the self-flowing of the well by internal flashing.

Assignee:
EDB-83-057216
Patent Number(s):
US 4364232
OSTI ID:
6536917
Resource Relation:
Patent File Date: Filed date 3 Dec 1979; Other Information: PAT-APPL-099674
Country of Publication:
United States
Language:
English