Odor assesment for WWTP?

Question

Is there any correlation factor for assessment of odor and other gases from waste water treatement plant in correlation with some parameter of the waste water, for instance such as COD, BOD5 etc. The main gases from WWTP are CH4, N2O, CO, CO2, NH3. I also need distribution in air assesment for these gases.

Answer 1

There are stoichiometric ratios between wastewater components and the gasses produced during treatment.  However because each WWTP has significantly different operating conditions the ratios can not be extrapolated to aggregate indicators such as COD or BOD.  One of the main odor causing gasses from WWTP is H2S from sulfate reducing bacteria.

I once worked at a plant that had aerobic sludge digesters.  If the air supply to the digesters was interupted for as little as an hour, the oder complaints from local businesses would start rolling in because the process would then favor the anaerobic microbes that produced more oderous gasses.

Answer 2

Most of the odor comes from storing the waste in holding tanks untik it is shipped out.  A methane burner shch as those found at refineries will go a long way to getting rid of the odor.  Also. emptying the holding tanks and cleaning them weekly will also help'

Answer 3

It can only be assesed from personal experience.

Answer 4

I know that hydrogen sulfide levels are measured in ppb in proximity to feedlots, but I'm not sure if it's the same for WWTPs.