Wednesday, May 11, 2011
There was a poster presentation at a NOWRA conference a few years ago relating hydraulic conductivity of the media to clogging potential. It was shown, and this should not come as a surprise, that low hydraulic conductivity media had a much greater probability of failing due to biological fouling than media with higher hydraulic conductivity.
During a recent presentation, Tchobanoglous stated that the size of the particles in the wastewater being applied had a significant effect on the bio-fouling potential of the media. If the particle size is close to the media pore size...clogging is likely. This explains, in part, why manufacturers are requiring larger and larger primary tanks and recirculation tanks for their systems; to try to reduce the size of the suspended solids so their media does not foul.
The sand filter shown above has already been rebuilt and the owners have decided to install an Eliminite system in its place. Our MetaRocks media has been proven over time and hundreds of installations to reduce the potential for biological clogging to near zero. The extreme efficiency of the media allows us to use smaller and fewer tanks while dramatically improving reliability and treatment characteristics.
Hydraulic acceptance rate of MetaRocks: >250 gal/min/ft^2.
Our goal has been to identify aspects of an onsite treatment system critical to its performance and optimize those aspects. The fundamental starting point is the media. If the media is not right, the system either will not work, or it will be a maintenance nightmare.
Highly robust media allows the system operation to be varied and optimized because there is no concern that the media will be overloaded. This fact leads to a variety of possible configurations and allows the designer to target constituents in the wastewater for treatment. Rather than treating the system with kid gloves, it handles dynamic conditions to the point of abuse. Isn't that what you really want in an onsite system?
We just received several Montana Cold Winter sample results for nitrogen, total nitrogen........The "worst" result was 12 mg/L TN. Montana cold, dead of winter, inspection not maintenance, no telephone link, just great results.
The best?...it was 4 mg/L TN.