Dewatering is a crucial part of the mining process because it helps create tailings that can be efficiently disposed of and reclaims water for use in other processes.
And selecting the right dewatering technology is just as crucial. The technology selected will depend on a variety of factors including:
mineral grind size
temperature and viscosity of materials
dewaterability of the concentrate
final moisture requirements
The chart below illustrates the different types of dewatering equipment and the various mining applications they are used in. Pay special attention to the first two columns that discuss high speed and conventional filter presses.
Now let's take a closer look at two of the applications mentioned in the chart, base metal mining and the Merrill Crowe process.
Filter Presses & Base Metal Mining
Base metals include: Copper, Zinc, Lead and Iron. Since base metals are mixed in with ore it is necessary to grind up the rock. Economic ore minerals (the base metals) are less than 2% of the total volume of the ore rock. So once the base metal as been separated out the remaining material must be dealt with.
Typically, the remaining material is mixed with thickeners to create a slurry that is dewatered using a filter press. It is important to select a filter press (like our MC Press® filter press) that will produce the driest and most compact filter cakes (or tailings). Compact tailings are easier to store and dispose of.
Filter Presses & the Merrill Crowe Process
The illustration above shows many components of the Merrill Crowe process.While filter presses are just one component, they are a crucial one. There are two very important design features to keep in mind when selecting filter presses (like our J-Press®filter press) to use in the Merrill Crowe process. These features are:
1. The ability to handle a high flow rate. Because the process deals with fewer solids, it requires high flow rate. Look for a filter press that has:
Oversized feed and filtrate ports in the plates
Oversized piping connections
2. The press must be made of materials resistant to CN corrosion.
Brass, bronze and galvanized parts are not allowed