AP Scrubber Question

[kuma]

Hello all! How are things today?
I hope all is well!
I'm sorry all , I have a question , regarding NaOH scrubbing for the AP process.
Is a Sodium Hydroxide scrubber only useful when using both hcl and h202 for the reaction , or will it still have a positive effect when using hcl and a bubbler alone ? :?:
Would I be right in guessing that it *would* still apply , as my thinking says copper-chloride , as in chloride , as in chlorine gas ?
Please bear with the noob! :mrgreen:
Many thanks in advance for any and all replies ,
All the best and kind regards ,
Chris

 

[4metals]

The caustic scrubber, if the fumes are retained long enough in the packed column, will be effective for AP and AR. The efficiency is maintained by periodic flushing of the packing and replacing the scrubbing liquid.

 

[kuma]

Hi 4Metals , thanks for the reply!
I'm thinking about somthing really small scale for now , about the scale of Nivrnb's AP set-up ( http://tinyurl.com/6l7eyc2 , thanks for the inspiration! :mrgreen: ).
With somthing this small , with a caustic scrubber around the same size , would the scrubbing solution need changing out after every day or so , or after every process had finished , say four days to a week ?
I'm sorry for the questions , I guess that I would just like to know that I have the process *down* before I even begin , :roll:
Many thanks again for the reply ,
Sending my kindest regards and best wishes ,
Chris

(Edited to find clarification , sorry! I'm a little confused with the terms "packed column" and "scrubbing liquid". Am I to use the NaoH in crystal/flake form , or am I to use liquid caustic ? , once again I appolagise for the questions! )

 

[4metals]

A packed column is what is tyically used in a fume scrubber to provide surface area for the caustic to interact with the fume which is bouncing its way up and out of the scrubber while the flow of caustic is flowing down over it.

The type of scrubbing you are talking about can also benefit from some type of media (marbles work well) which will cause the path of the fume going through the liquid to be extended and hence have more contact time.

The type of scrubber you are considering is run by adding some caustic to the scrubbing water to get the pH up to 10 or so and the fumes react with the caustic and are neutralized. You will learn from practice how much AP you can process before replenishing the caustic.

 

[kuma]

Hello again!
I think I've got it now , I actualy recall reading about using marbles for this to expand surface area a while ago. It's so simple , it's genius! :idea:
Many , many thanks to you , and for sharing what it is that you do!! :mrgreen:
Once again , I wish you all the very best and send my kind regards ,
Chris

 

[Alentia]

Is Urea a better use in scrubber instead of NaOH?

Urea is used in SNCR and SCR reactions to reduce the NOx pollutants in exhaust gases from combustion from diesel, dual fuel, and lean-burn natural gasengines. The BlueTec system, for example, injects water-based urea solution into the exhaust system. The ammonia produced by the hydrolysis of the urea reacts with the nitrogen oxide emissions and is converted into nitrogen and water within the catalytic converter.

 

[qst42know]

SNCR and SCR reactions

I had to look them up but, those are flue gas scrubbers (power plant & boiler), performed hot and large scale. Without the high temperatures urea may not scrub at all.

Cut from wiki.

The ideal reaction has an optimal temperature range between 630 and 720 K, but can operate from 500 to 720 K with longer residence times. The minimum effective temperature depends on the various fuels, gas constituents and catalyst geometry. Other possible reductants include cyanuric acid and ammonium sulfate.[3]

Full description and chemestry.

http://en.wikipedia.org/wiki/Selective_catalytic_reduction

 

[Geo]

wouldn't it work just letting it vent into the bottom of a glass container full of dry sodium bicarbonate. the fumes would have to work their way through the baking soda to get out. just a thought.

 

[qst42know]

I would expect moisture would solidify the sodium bicarbonate and stop the flow of gas.