Abstract

The paper describes the design, realization and 10 years of operation of the filtration part of a mine backfill project/operation in Europe. It starts with the selection of filter type (vacuum disc filter) and the filter sizing, both based on a sample provided by the customer. The paper continues with the commissioning of the filter units and reports on the development of the filter performance during the following 10 years of operation.

The paper first describes the physical properties of the sample and the process targets of the client for the backfill plant. It shows the logic steps taken in the laboratory to first determine the pressure difference (vacuum) and the filter setting required to reach the moisture target. It further describes, how the filtration area gets optimized using flocculant and filter rotational speed while still keeping the moisture below target level. This sizing optimization step is very important as it has a major influence on the CAPEX of the project. In the last sizing step, the ancillary units such as vacuum pumps were sized based on the test results and finally the paper describes the criterias used to get from the laboratory test results to the process performance guarantee.

After supply and installation of the filter, the commissioning started. The paper discusses some issues with filter operation during the commissioning phase, possible solutions discussed at that time and final measures that have been taken to successfully fix the issues. It also touches some mechanical issues that developed over the years based on an increasing ion content of the process liquid. Finally, the paper concludes by highlighting the gradual change of the filter feed observed over more than 10 years of operation experience and how this change affected filter performance and operating costs