10 Conclusion
The technical feasibility of the innovative flotation-filtration FF-Cell system for
producing a high-quality effluent has been successfully demonstrated by continuous
pilot plant operation. An existing secondary biological wastewater treatment plant
can be easily upgraded by the addition of an FF-Cell to produce an effluent having a
water quality compatible with water reuse requirements. The capital cost of such a
system is low because of its short detention time and unique compact design.
Glossary [49–51]
DAF Dissolved air flotation process.
DAFF Dissolved air flotation and filtration.
Dissolved air flotation (DAF) One of dissolved gas flotation (DGF) processes
when air is used for generation of gas bubbles. See dissolved gas flotation (DGF).
Dissolved gas flotation (DGF) It is a process involving pressurization of gas at
25–95 psig for dissolving gas into water, and subsequent release of pressure (to 1
atm) under laminar flow hydraulic conditions for generating extremely fine gas
bubbles (20–80 microns), which become attached to the impurities to be removed
and rise to the water surface together. The impurities or pollutants to be removed
are on the water surface are called float or scum, which scooped off by sludge
collection means. The clarified water is discharged from the flotation clarifier’s
bottom. The gas flow rate is about 1% of influent liquid flow rate. The attachment
of gas bubbles to the impurities can be a result of physical entrapment, electrochemical attraction, surface adsorption, and/or gas stripping. The specific gravity
of the bubble-impurity agglomerate is less than 1, resulting in buoyancy or
nonselective flotation (i.e. Save-All).
F-Cell Dissolved air flotation cell or DAF.
FF-Cell Dissolved air flotation and filtration cell or DAFF.
Flotation cell A dissolved air flotation cell or unit process.
Flotation-filtration cell A package treatment plant, which consists of both
dissolved air flotation and filtration unit processes.
Package treatment plant A prefabricated water or wastewater treatment plant
consisting of two or more unit processes.
Primary flotation clarification A dissolved air flotation clarification process,
which is used for primary clarification of wastewater, with a main purpose of
total suspended solids removal.
Secondary flotation clarification A dissolved air flotation clarification process,
which is used for secondary clarification of wastewater, with a main purpose of
either: (a) removal of biological sludge from a biological oxidation process, or
nitrification process or (b) removal of chemical sludge from a secondary physicochemical process mainly for removal of dissolved organics, heavy metals, etc.
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N. K. Shammas et al.
The technical feasibility of the innovative flotation-filtration FF-Cell system for
producing a high-quality effluent has been successfully demonstrated by continuous
pilot plant operation. An existing secondary biological wastewater treatment plant
can be easily upgraded by the addition of an FF-Cell to produce an effluent having a
water quality compatible with water reuse requirements. The capital cost of such a
system is low because of its short detention time and unique compact design.
Glossary [49–51]
DAF Dissolved air flotation process.
DAFF Dissolved air flotation and filtration.
Dissolved air flotation (DAF) One of dissolved gas flotation (DGF) processes
when air is used for generation of gas bubbles. See dissolved gas flotation (DGF).
Dissolved gas flotation (DGF) It is a process involving pressurization of gas at
25–95 psig for dissolving gas into water, and subsequent release of pressure (to 1
atm) under laminar flow hydraulic conditions for generating extremely fine gas
bubbles (20–80 microns), which become attached to the impurities to be removed
and rise to the water surface together. The impurities or pollutants to be removed
are on the water surface are called float or scum, which scooped off by sludge
collection means. The clarified water is discharged from the flotation clarifier’s
bottom. The gas flow rate is about 1% of influent liquid flow rate. The attachment
of gas bubbles to the impurities can be a result of physical entrapment, electrochemical attraction, surface adsorption, and/or gas stripping. The specific gravity
of the bubble-impurity agglomerate is less than 1, resulting in buoyancy or
nonselective flotation (i.e. Save-All).
F-Cell Dissolved air flotation cell or DAF.
FF-Cell Dissolved air flotation and filtration cell or DAFF.
Flotation cell A dissolved air flotation cell or unit process.
Flotation-filtration cell A package treatment plant, which consists of both
dissolved air flotation and filtration unit processes.
Package treatment plant A prefabricated water or wastewater treatment plant
consisting of two or more unit processes.
Primary flotation clarification A dissolved air flotation clarification process,
which is used for primary clarification of wastewater, with a main purpose of
total suspended solids removal.
Secondary flotation clarification A dissolved air flotation clarification process,
which is used for secondary clarification of wastewater, with a main purpose of
either: (a) removal of biological sludge from a biological oxidation process, or
nitrification process or (b) removal of chemical sludge from a secondary physicochemical process mainly for removal of dissolved organics, heavy metals, etc.
68
N. K. Shammas et al.