Structure and Controlling of a Pump Station to an Injection System

I was assigned to the thesis as part of a project GMA AB (Ground Machinery Applications AB) is running. The project aims to develop a new method for injection of drilled holes in rock walls. Currently, the injections usually involve cement but the basic idea of the project is to replace cement with a supplement called Silica sol. Silica sol is known as a gelling liquid. The gel time is controlled by a mixing of saline. Depending on the amount saline that gets mixed in, the gel time varies. By controlling the ratio of Silica Sol and saline during an injection, you can make all the Silica sol and saline harden simultaneously and that consequently affect how deep into the rock wall the gelling fluid ingress. To the project GMA bought a pump station which was previously used in a similar project. The purpose was to review the pumping stations components and if possible, use these to meet the objective. During the project two proposals of the pumping system structure were considered. The proposal that was considered to be the best were chosen based on practical criteria. The existing pump station components were supplemented with new components and a pumping system was built up by the developed proposal. The pumping stations associated electrical box was rebuilt to meet the requirements of the system and a Mitsubishi PLC system was implemented and drawings of the electrical components were made. Then a program to control the pump station manually was created in order to verify that the components were connected properly. Then a program containing a PID controller was created in order control the ratio of silica sol and saline and also to maintain the required pressure in the system. The pump station was tested against a water tank and two methods for frequency based regulation setting were used to set the PID controller parameters. Part of the goal which unfortunately did not get realized due to lack of time was to test the pump station against a pipe that was built to simulate a real drilled hole. Therefore the PID parameter setting did not get optimized for a proper injection with silica sol and saline. Based on the results and all the progress, this report will be a good base to start from when someone chooses to proceed with this project