The chlor alkali industry frequently uses conventional brine treatment and polish filtration with pre-coat type filters. After saturation, the brine is chemically treated in one or more reactors. Most of the solids are separated in a clarifier where additional residence time is used to further precipitate contaminants (e.g. silica).

Brines produced by solution mining can contain chemicals suppressing the solubility of sulfates (Sulfate Solubility Inhibitors – SSI). Some types of SSI may have an adverse reaction to PTFE Tefflux membranes. If these chemicals are present in the raw brine, then pre-coat filtration (cellulose) is in some cases preferred.

In order to minimize filter aid consumption, the solid load to the pre-coat polishing filters should be kept at a low level. The installation of anthracite pre-clarification filters can assist with that.

ProFilco offers two types of brine pre-coat filters used for brine polishing: LEAF TYPE FILTERS and CANDLE TYPE BACK PULSE FILTERS

The pressure leaf filter generally has a larger footprint and is more capital intensive to install.

ProFilco’s candle type pre-coat filters have the advantage that PTFE TEFFLUX MEMBRANES can be installed for single stage non-pre-coat filtration at a later time.

CANDLE TYPE BACK PULSE FILTER

The candle type back pulse filter system is the most economical type of filter for brine purification.

PRESSURE LEAF FILTER

The pressure leaf filter generally has a larger footprint and is more capital intensive to install.