Water Environment Federation (WEF) Discussion Forums / Biosolids & Residuals / WEF Discussion Forums / Caustic Hypochlorite Scrubber on ATAD Offgas / Latest Posts

RE: Caustic Hypochlorite Scrubber on ATAD Offgas

S. Hoppe — Mon, 05 Nov 2007 11:45:06 GMT

May I draw your attention towards an odour control system based on photo-catalytic oxidation (PCO)?

This technology is very maintenance-friendly and highly effective in treating ATAD off-gas.

There are many WWTP in Europe applying PCO for various applications, including ATAD. At the moment, as part of a new integrated ATAD-concept (ATAD AIC), a PCO will be installed in West Virginia.

As pilot tests have been run successfully, a great future for PCO can be expected in the USA too.

For more information please visit:

http://www.fuchs-germany.com/

Steffen

Fuchs Germany

RE: Caustic Hypochlorite Scrubber on ATAD Offgas

HForbes — Fri, 02 Nov 2007 14:03:08 GMT

CO2 absorption rates are highly dependent on the pH of the scrubbing solution. ATAD is an aerobic process and therefore, when designed and operated properly, it produces little hydrogen sulfide. You definitely want to have caustic as part of the design in case of process upsets which may cause spikes in H2S and to elevate the pH slightly to aid in the removal of organics, but as a general rule you should be able to operate the scrubber at a pH around 9.5, which means you will absorb relatively little CO2.

RE: Caustic Hypochlorite Scrubber on ATAD Offgas

dswolf — Fri, 02 Nov 2007 08:52:12 GMT

I am currently evaluating a biofilter for odor control at treatment plant in North Carolina. These systems can achieve a 99.9% removal efficiency when optimum operation conditions are maintained. Carbon adsorption units are also commonly used to control odor and VOC emissions.

David

RE: Caustic Hypochlorite Scrubber on ATAD Offgas

Rob Baur — Thu, 01 Nov 2007 10:55:23 GMT

The only ATAD unit near here (Oregon) had a hypo odor control system. The best that could be said was "it smelled like a chlorinated dead cat". They switched to a biofilter that uses chipped roots and trunks. The theory is they are innoculated with soil bacteria and are more resistant to decomposition. It is very effective. On line 10 years. http://www.ambio.ca/

I would call ATAD sites and see what they are using.

Caustic Hypochlorite Scrubber on ATAD Offgas

01780898 — Wed, 31 Oct 2007 22:43:45 GMT

We are proposing to install acid (H2SO4) then caustic-hypochlorite scrubbers on ATAD offgasses for odour control. We have done some calculations, which suggest that there will be a high caustic soda demand for the scrubber, due to the quantity of CO2 produced in the ATAD process. Does anybody have any expertise in this area and could provide estimates of chemical consumption?

Thank you

Grant