From: Debra Jacobson (email@example.com)
Date: Mon, 12 Jan 2004 15:41:12
I worked with our lab on this issue several years ago. We found that membrane filtration is not really cost effective. We tested many different chemicals to flocculate the suspended solids out of water based flexographic wastewater. Flocculents that worked the best and was reasonably priced was calcium chloride. Other chemicals that worked well were Hydrochloric Acid and Hydrogen Chloride. Sodium Chloride (NaCl) can be used, but it does not coagulate nearly as fast as the others. The supernatant liquid from the Calcium Chloride (CaCl2) was clearer compared to the HCl addition.
Eventually a couple of printers in Illinois have utilized this research and assembled settling tanks/discharge systems at their facilities based on the above research and our assistance.