Installation and removal of submersible centrifugal pumps for the extraction of geothermal mine water and execution of test work
Stadtwerke Bochum Holding GmbH (AG), through its associated company Fernwärmeversorgung Universitäts-Wohnstadt Bochum GmbH (FUW), has drilled two geothermal wells on the site of the former Opel plant in Bochum. The boreholes are intended to be used for the use of mine water from the disused Dannenbaum colliery for the heating and cooling supply of the renovated Mark 51°7 industrial estate in Bochum Laer.
The two boreholes were drilled from a cluster site into two abandoned and flooded sections of the former Dannenbaum mine in order to alternately lift mine water for heating in winter and cooling in summer. The first well, the GT2, reached a depth of 334 m, while the second well, the GT1, was drilled to a depth of 864 m. After drilling the roadways, a resting water level of approx. 230 m was established in both boreholes.
It is planned to test both wells for their performance by means of pump tests. Against the background that there is no storage capacity for mine water on the location, circulation tests including both wells are planned for the evaluation of the boreholes. After the installation and commissioning of a submersible centrifugal pump into the first borehole (GT2), the pumped mine water after flowing through a mobile test station and a tank, is to be sunk into the reinjection bore (GT1). After recording all parameters important for the evaluation of the boreholes, this test is to be repeated in opposite directions after removal and reinstallation of the submersible centrifugal pump in the second borehole (GT1).
The scope of services includes the installation and removal of the submersible centrifugal pump in both boreholes, the execution of the pump tests and the performance measurement in the planned period from January 2022. Furthermore, the scope of services includes the final completion of both boreholes, i.e. in particular the installation of two submersible circuit pumps for continuous operation in the period between November 2023 and June 2024. The exact execution period will be agreed in good time.