The presentation will discuss lab testing, pilot testing, scale-up, installation and performance guarantee for the BHS candle filter technology. The overall scheme can be used by process engineers to develop optimum filtration solutions for pressure or vacuum, batch or continuous and high-solids to clarification applications.
This customer presently filters a specialty chemical in a filter press using a paper filter media at 170 degrees C. Diatomaceous earth and/or activated carbon are used as a body feed and precoat. The material is dried with nitrogen and the solids are removed and burned in the power plant as fuel. The process has the typical problems associated with a filter press including bypass of slurry, manual operation, filter media plugging, non-reproducible quality plus the safety concerns of being burned with hot oil.
BHS began the application with laboratory testing using the BHS Pocket Leaf Filter. These tests determine pressure filtration, cake thickness, filter media, cycle times and quality parameters such as filtrate quality and final moisture content. The lab testing showed that the BHS Candle Filter is the correct technology for this application.
Following the lab testing, the plant then rented a pilot candle filter with 1 m2 of filter area. The objectives of this testing is to confirm the lab testing, observe cake discharge and develop the design parameters for the final scale-up and performance guarantees. The presentation concludes with a description of the installation, PLC controls and performance guarantees.