Natisha writes:
Hi,
I am designing an adsorption unit for the removal of VOC gases using activated carbon. Can anybody help me with how I should go about designing the adsorption bed?
I would suggest looking at the websites of existing manufacturers of Adsorption Equipment for a list take a look at http://process-equipment.globalspec.com/specsearch /suppliers?Comp=3168 . A review manufacturers' website should give you an idea of the types of Adsorption Equipment available and possibly the construction and technology used in their manufacturing. Sorbents like activated carbon are used within the adsorption systems to capture the volatile organic compounds. For a list of suppliers of Sorbents and Dessicants, take a look at http://materials.globalspec.com/SpecSearch/Supplie rs/Materials_Chemicals_Adhesives/Chemicals_Raw_Mat erials/Desiccants_Absorbents?frmtrk=smartbox&SrchI tem=1 .
Natasha, if I am in your place, I would be looking at Zeolites as an alternative to activated carbon adsorbtion. The reasons are many. Firstly, Zeolites are easier to handle and dont mess the place when you handle them. The Zeolites can adsorb VOCs and also water vapour and any toxic gases which may be in the mixture of VOCs. Zeolites can be recharged once saturated by simple methods. Zeolites will work out cheaper and more abundant compared to activated carbon. Zeolites can be obtained in various grades and sizes to suit any application and hence much easier to design beds. If you think Zeolite can be alternative to carbon, then let me know. I can be of help.
I once worked for a "gentleman" who was too frugal to purchase a carbon absorber of "proven design". He decided to design one himself and have two units fabricated, operation was to be alternating service. Shortly after start-up/testing...One unit caught fire (during the night) and nearly burned the plant down. This led to a somewhat hasty installation of fire suppression system and complete rebuild of the "toasted" unit. Add to that an expression of concern from the local fire chief, I won't say where.
It was discovered shortly thereafter that, the units did not perform up to expectations, nor to regulatory requirements. That's when things got a little too dicey.
Carbon absorbers are not simple to design and if you don't have the time to start out on a bench scale and test, you should consider hiring a design firm with expertise in this area, or purchase a catalog unit with adequate capacity for your application.
we have plan to install activated carbon adsorbtion for VOC adsorbtion. can you give me detail benefits of zeolites over activated carbon ? If there will be a more benefits then we can change our plan...