MOST subscriber Dan asked us recently how important Flash Mixing is for the ACTIFLOW process. A very good question, Dan. And here is our reply:
Dan: I’m no expert on the ACTIFLOW system, but the chemistry of coagulation has to be the same as in a conventional process. And that means that mixing is critical. Every pathogen is colloidal in size, and the sedimentation and filtration processes that would follow an ACTIFLOW process are not effective at colloidal particle removal. The purpose of coagulation and flocculation — and ACTIFLOW, for that matter — is to convert colloidal particles into larger, suspended particles. And these larger particles can be removed by sedimentation and filtration, thus enabling us to effectively remove pathogens in conventional treatment.
But the process of transforming colloidal particles into suspended ones requires two things: first, a change in colloidal surface chemistry, and second, collisions among these “destabilized” colloidal particles. And these are two very different kinds of mixing. Both are absolutely critical to process success! The Flash Mix term is usually used in reference to the first of these two mixing processes. It is here that our primary coagulant — ferric chloride in your case — must come into direct physical contact with the surface of each colloidal particle.
MOST course WT-2 tells you all about the process of coagulation and the vital importance of mixing in this process. And like all of our courses at MOST, this is a one-hour, online video that you can purchase at any time for only $10. And you can play it as many times as you like for a full year after purchase. And when you’re finished watching it the first time, you can print out a certificate of completion which the State of California recognizes as one contact hour of continuing education toward the renewal of your Water Treatment or Water Distribution Operator certification.
The WT-2 Coagulation video — as well as WT-3 on Flocculation — is found on the 24-video MOST Water DVD collection as well. And the entire collection is only $120 — only $5 per video. It would be a terrific training resource for folks like Dan! Just “Contact” us from the MOST web site for ordering information.