Larox PF pressure filter

1. FILTRATION

The process slurry is pumped into all filter chambers simultaneously. The solids begin to form as the filtrate is displaced by more slurry entering the chamber. As the solids build, the pumping pressure increases, and filtrate is forced through the cloth until the required solids thickness is achieved.

2. DIAPHRAGM PRESSING I

High-pressure air or water automatically inflates the diaphragm located at the top of each chamber, reducing the chamber volume and squeezing the solids to remove more filtrate. The solids filtration process and tightly woven filter cloth produces exceptionally clear filtrate, while the high pressure maximizes filtration efficiency. Diaphragm pressing produces homogenous dewatered solids of uniform thickness with minimal excess liquid, assisting washing and air blowing.

3. SOLIDS WASHING

Outotec Larox® pressure filters can wash dewatered solids in-situ to maximize solute removal or to recover the mother liquor with minimal dilution. The wash liquid is distributed evenly because the solids are homogenous and the filter plates lie horizontally. The wash liquid flows through the solids, displacing the mother liquid with minimal mixing.

4. DIAPHRAGM PRESSING II

The diaphragms are re-inflated, forcing the wash liquid uniformly through the solids. This produces a washing efficiency of over 95%, with consistent dry solids quality and minimum wash liquid consumption.

5. AIR BLOWING

Compressed air is blown through the solids for final dewatering. The moisture content is minimized and can be controlled precisely by adjusting the pressure and duration of the air blow.

6. SOLIDS DISCHARGE AND CLOTH WASHING

After the plate pack opens, the dewatered solids are conveyed out of each chamber on the moving filter cloth. The integrated wash unit sprays both sides of the cloth with high-pressure water, minimizing cloth blinding and ensuring consistent filtration results.