| Treatment
Technology: Fixed
Activated Sludge (FAS) Treatment |
This
technology utilizes an aerobic fixed film process that
is a combination submerged attached growth and activated
sludge processes. This system is designed to be installed
into a two compartment septic tank, where the first compartment
provides solids settling, and the second contains the treatment
module. Rigid block-type media is submerged within the
treatment module, providing surface area for microbial
growth. Aeration and wastewater circulation are supplied
by a blower unit that pumps air into the center of the
block media. Aerated wastewater comes in contact with the
rigid block media where nitrification of wastewater is
thought to occur. Denitrification is thought to occur in
the anaerobic portion of the unit (distal areas away from
the active aeration zone). Wastewater transfer through
the system is by hydraulic displacement, so wastewater
transfer will occur even if the power to the blower unit
is lost. Note that treatment of the effluent relies on
the function of the blower unit; if the blower power is
lost, effluent discharged from the system will likely be
of poor quality. |
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| A
treatment train incorporating fixed activated sludge
treatment |
Wastewater exits the home through a gravity-flow building
sewer (A) and enters a two-compartment tank (B). A blower
(C) supplies air to the advanced treatment portion of the
tank, in the second compartment. The first compartment is
a septic/trash compartment where solids settle. The second
compartment houses the fixed activated sludge unit. Wastewater
moves through the unit by gravity displacement, with processed
wastewater flowing into the drainfield pump basin (D). A
pump located in the drainfield pump basin doses effluent
to a shallow narrow drainfield (E).
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| Treatment
performance observed for FAS treatment systems in RI |
| System
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BOD5
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TSS
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TN
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%
TN Reduction
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Fecal
Coliform
CFU
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| Coming soon.... |
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| For
more information on fixed activated sludge treatment: |
| Web Links: This
technology is a proprietary device under the trade name MicroFAST® Wastewater
Treatment System, manufactured by Biomicrobics Incorporated.
For more information on this treatment technology, see the
vendor website at www.biomicrobics.com |
