Yes there is an sensor available from Unisens in Denmark, it is called "miniaturized clarke cell, " http://www.unisense.com/N2O " You also need a quite expensive picologger from the same firm

thanks @ Kåre Tjus. i have one more query. how to measure the gaseous nitrous oxide ? is there any sensor available for that like aqueous nitrous oxide.

Hello Chitta, We have been using Infrared sensor from Teledyne, http://www.teledyne.com/ or from ADChttp://www.adc.co.uk/Air , it s very importan to avoid water into the analyzer to protect it.

Can you give a rough number of production of nitrous oxide production from municipal waste water treatment in ppm .

100-200 ppm or lower, depends on process, we have sometimes seen values such high as 70000 ppm. Howeverer we was then looking on treatment of very nitrogen rich water

Wow!!!!! 70000 ppm is quite interesting. Did you find this range of nitrous oxide production in industrial waste water or municipal waste water treatment?? Can you add detail to this point?

municipal wastewater , well there is an conference paper regarding these measurements, I can send it to you

Here come s the Abstract

We found that when there was a problem with the denitrification due to low ethanol addition there was an increase in nitrite followed with very high nitrousemissions, we don not yet have the whole picture

"

Oxygen induced dynamics of nitrous oxide in water and off-gas during treatment of digester supernatant

F. Stenström*,***, K. Tjus** and J. la Cour Jansen***

* VA-Ingenjörerna AB, Trädgårdsgatan 12, SE-702 12 Örebro, Sweden

(E-mail: [email protected])

** IVL Swedish Environmental Research Institute, P.O. Box 210 60, SE-100 31 Stockholm, Sweden

*** Water and Environmental Engineering, Department of Chemical Engineering, Lund University, SE 221 00 Lund, Sweden

ABSTRACT

Nitrous oxide (N2O) is a potent green house gas and of special concern in wastewater treatment. It is formed in biological wastewater treatment under both aerobic and anaerobic conditions. High N2O emissions are favoured by low oxygen concentration during nitrification. In this full scale study of N2O emissions from an SBR for treatment of digester supernatant, the oxygen concentration was reduced stepwise to investigate how N2O emissions were influenced. Concentrations of N2O were measured online in water as well as in off-gas. A distinct relationship was shown between low oxygen concentration and high N2O emissions. N2O was formed in water under both nitrification and denitrification. Decreased oxygen concentration during nitrification implied increased nitrite concentration, which in turn implied increased concentration of N2O in the subsequent denitrification phase. When the nitrification started again, accumulated N2O was stripped off to the atmosphere. Very high concentrations of N2O in the off-gas were measured, over 56,000 ppmv. Furthermore, the maximum amount of N2O emitted during one cycle corresponded to 108% of the total nitrogen load (21.9% of present total nitrogen in bulk liquid at the beginning of the cycle). This is among the highest emission that has ever been measured from a full scale municipal plant for digester supernatant.

Keywords: Biological wastewater treatment, Digester supernatant, Nitrous oxide, Sequencing batch reactor

Very interesting result.

Can you send me this paper on my email id- [email protected]