View this email in your browser
Volume 09 Issue 01
  Volume 9 Issue 2 BHS-Sonthofen Inc. June 19, 2018  
     Featured Article | Technology Application | Innovations | Upcoming Events | Blog | Book

Focus:  Filter Aids and Clarification Technologies

Welcome to Year Number 9 of A&SoF. It’s June already and we are all preparing for the summer so safety is critical as we enter this time of the year.  In the first newsletter of 2018, the theme was “speed.”  In all of our endeavors, the speed of information flow, decision making, world events, politics, etc., is increasing dramatically.  From a business point of view, technology, marketplace, competition, manufacturing, etc. are all changing at breakneck speed.  However, if we think about safety in the summertime, let’s slow down our speed.  
This issue focuses on filter aids.   The first article is from Chemical Engineering and presents an over of filter aids.  BHS has taken this one step further and has conducted testing to provide guidelines for filter aid usage.  We believe that this is a unique perspective, let us know what you think and your ideas for further research.        

As always, thanks again, to our readers, for your feedback and if you missed any issues, please click on the following link: to view them.   


Barry A. Perlmutter

Featured Article:

Facts At Your Fingertips:  Filter Aids

Department Editor:  Scott Jenkins, Chemical Engineering, November 2017, p. 28

Cake filtration is a common operation across many sectors of the chemical process industries (CPI).  In some cases, filtration can be difficult if the material being filtered is highly viscous, highly compactible or deformable, or if the filter cake formed in the filtration is very small or highly resistant to flow. For such situations, the addition of filter-aid material can greatly improve the efficiency and effectiveness of the filtration. This one-page reference provides information on the properties and usage of common filter-aid materials.     

BHS Technology Application:

Relationship, Selection, and Optimization of Filter Aid, Filter Media and Clarification Technologies for Contaminant Fines Removal from
Process Slurries and Liquids

Garrett Bergquist, BHS Process & Application Engineer

In many chemical processes there is the need to remove fine solid contaminants less than 5 microns (µm), from process liquids. When the suspended solids content is dilute, typically less than 1% by weight, the removal process is called clarification or polishing filtration to produce a clean liquid product. Often in polishing applications the solids are very fine or amorphous which can be difficult to filter. When filtered, the solids will create a thin coating over the filter media and immediately reduce the filtration rate to an unacceptable level. In these difficult filtering cases, filter aids can be used to improve filtration properties and efficiently remove the fine solids from the process liquids.

This paper discusses the use and selection of filter aid and filter media in conjunction with clarification technologies for the removal of fines from chemical process liquids. The article continues with case studies performed to determine the ideal ratios of filter aid to body feed to the suspended solids content as well as to the particle size distribution of these fines.


BHS Rubber Belt Filter for filtration and heavy metal washing of fly ash from process – grey water

The BHS rubber belt filter is installed for fast filtering products on a continuous basis.  The BHS design eliminates the sliding water which is a significant savings of operating and disposal costs.  Testing and rental units are available for trials.
ERZ Service has installed the BHS rubber belt filter, RBF 200-100 to process 5,000 tons of fly ash per year for filtration, heavy metal washing / leaching and drying.  Please see the reference video for the installation details and operation including cake discharge.


Best Practices for Filtration Testing for Solid-Liquid Separation

Testing in school has a negative connotation. Students dread tests. Parents bemoan “teaching to the test.” Teachers chafe against the curriculum parameters defined by testing expectations. Yet, the word “testing” should resonate much more positively with process engineers. After all, testing is the key for selecting the most suitable filtration tech for any individual solid-liquid separation task. By identifying the role of each influencing part, the process engineer gains a potential tool to work with when it comes to understanding testing findings and developing a path forward in determining the best filtration procedure.
Just from experience, and for the benefit of engineers, some overview observations are necessary:

  • Don’t stop testing just because the first results suit your target
  • Don’t accept samples without verifying the parameters in the description
  • Never change more than one parameter at a time
  • One result is no result => verification is a must
  • Take a break and check the conformity of the results before you call it a day

Upcoming Events:

  1.  International Biomass Conference:  Atlanta, 16 – 18 April 2018, Improving Biochemical Process Operations with Continuous Pressure and Vacuum Filtration Technologies,
  1.  AICHE Process Development Division Plenary Session:  Orlando, 23 April 2018, Upgrading a Zinc Oxide Process to Continuous Vacuum Filtration from Batch Filter Presses,
  1.  World Congress on Particle TechnologyOrlando, 26 April 2018,  Real World Examples of Influences of Particles and Cake Formation on Solid-Liquid Separation Technology Operation,
  1.  Flow Forum Insights for Process Efficiency:  Chicago, 7 – 8 May 2018,  Benefits of upgrading to continuous vacuum filtration from batch filter presses,
  1.  ACHEMA 2018:  Frankfurt, Germany, 11 – 15 June 2018, Hall 5.0, Stand C-34,

Solid-Liquid Filtration Practical Guides in Chemical Engineering

BookBarry Perlmutter President & Managing Director
BHS-Sonthofen Inc.

Read the Book

Barry Perlmutter President & Managing Director of BHS-Sonthofen Inc. has written An essential guide to the basic principles and mechanisms of filtration, to ensure you make the right filtration choices.

Copyright © 2018 BHS-Sonthofen, Inc., All rights reserved.
BHS-Sonthofen, Inc.
14300 South Lakes Drive
Charlotte, NC 28273-8794
Phone:  704-845-1190

BHS specializes in thin-cake filtration, washing, and drying technologies for pressure or vacuum, batch or continuous operation for high solids and clarification applications.

Want to change how you receive these emails?
You can update your preferences or unsubscribe from this list.