17-05-2010, 08:28 AM
Bio-Oxidation
Biological air-pollution control technology has been used extensively. The factors that restricted the use of bio -oxidation are:
-the relatively large size of the units
-the weight of these biofilters precluded their placement on a building roof
-the compliance assurance monitoring
(CAM) regulations of the 1990 Clean Air Act
Amendments require verification of control equipment
performance on a continuous basis
The changing landscape
Bio oxidation facilitators in the form of biofilters, biotrickling filters and bioscrubbers have been made available. In a biofilter microorganisms are attached to a substrate
and a non-bioactive humidification system maintains
the proper moisture level.A bioscrubber is a water-scrubbing device with a suspended
microbial component through which water
recirculates. Bioscrubbers may be designed to use the
effluent (non-chlorinated) from an extended-aeration or activated-sludge type wastewater treatment plant. In a biotrickling filter, microbes
are attached to natural or artificial substrates,
and water for humidification and the stream to be
treated flow over the substrates and are recirculated.
Operational factors:
Moisture:
The bed of biomass must be neither too dry nor too
wet (flooded).the biomass
will die if dry and the biomass may wash out or be drowned if wet.
Temperature:
Temperature controls the metabolism of the microbes.a warm (approximately 25“35°C) biooxidation unit will generally support more organisms,
both in terms of the number of organisms and the number
of species, at higher activities (metabolic rates).
pH:
Bioreactors
can function at pHs ranging from as low as 2“3 to as
high as 8 or 9. careful attention
must be paid to the pH of the system since the chlorinated and sulfur-containing compounds
produce acids upon biological degradation.
for more details, refer the pdf links given in the previous reply in this thread
Biological air-pollution control technology has been used extensively. The factors that restricted the use of bio -oxidation are:
-the relatively large size of the units
-the weight of these biofilters precluded their placement on a building roof
-the compliance assurance monitoring
(CAM) regulations of the 1990 Clean Air Act
Amendments require verification of control equipment
performance on a continuous basis
The changing landscape
Bio oxidation facilitators in the form of biofilters, biotrickling filters and bioscrubbers have been made available. In a biofilter microorganisms are attached to a substrate
and a non-bioactive humidification system maintains
the proper moisture level.A bioscrubber is a water-scrubbing device with a suspended
microbial component through which water
recirculates. Bioscrubbers may be designed to use the
effluent (non-chlorinated) from an extended-aeration or activated-sludge type wastewater treatment plant. In a biotrickling filter, microbes
are attached to natural or artificial substrates,
and water for humidification and the stream to be
treated flow over the substrates and are recirculated.
Operational factors:
Moisture:
The bed of biomass must be neither too dry nor too
wet (flooded).the biomass
will die if dry and the biomass may wash out or be drowned if wet.
Temperature:
Temperature controls the metabolism of the microbes.a warm (approximately 25“35°C) biooxidation unit will generally support more organisms,
both in terms of the number of organisms and the number
of species, at higher activities (metabolic rates).
pH:
Bioreactors
can function at pHs ranging from as low as 2“3 to as
high as 8 or 9. careful attention
must be paid to the pH of the system since the chlorinated and sulfur-containing compounds
produce acids upon biological degradation.
for more details, refer the pdf links given in the previous reply in this thread