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VOC abatement with the help of ionisation 3
- Thread starter MrStout
- Start date
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I agree with Peter AB - Ionisation systems for VOC control are not scientifically based!!!
Having said that it is possible to treat organic odours at very low concentrations using Active Oxygen systems.
Generally your options for VOC abtament will include
Thermal oxidisers
Regenerative Thermal Oxidisers
BioFilters
Activated carbon systems
Contact Clean TeQ in Australia for further details.
ctairman
info@cleanteq.com
Having said that it is possible to treat organic odours at very low concentrations using Active Oxygen systems.
Generally your options for VOC abtament will include
Thermal oxidisers
Regenerative Thermal Oxidisers
BioFilters
Activated carbon systems
Contact Clean TeQ in Australia for further details.
ctairman
info@cleanteq.com
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- #4
Dear MrStout,
A little information about ionization of VOCs. First, if you are going to ionize any VOC in an exhaust vent be ready to buy an extremely large generator - may I suggest a GE LM2500 gas turbine generator. In lieu of ionizing the VOCs, if your exhaust stream has a sufficient amount of oxygen, simply pipe it into the compressor of the gas turbine engine. A very cost efficient thermal oxidizer that generates electricity. If your vent gas has a concentration of VOCs that is above the LEL, the piped it into the exhaust of the gas turbine engine that is retrofitted with an afterburner!
Now with that being said, what is the source for the VOCs? Refinery vent gas, glycol recovery unit, paint booth, VCM oxi plant, etc.?
Here is a little information that may be helpful, but boring to read:
It is very possible to treat VOCs with a photocatalyst. But beware of the UV light source. Keep in mind that the reason VOCs are permitted is because of carcinagenic properties (benzene) and also because of the photocatalytic reaction between NOx, VOCs and sunlight (UV light at a wavelength of 365 nm). It produces smog, which is ozone. So can this reaction be controlled within a process stream. Absolutely. see my US patent #5,832,361 on USPTO website:
I noticed that Mr. Ctairman suggested the use of active oxygen. However, he did not suggest how you would produce the active oxygen. Active Oxygen is a misnomer for singlet oxygen. It is the first step that occurs when vacuum UV photons (185 nm and below) strike an oxygen molecule. The oxygen cleaves into two oxygen atoms with unpaired electrons. Thus, one could say that the oxygen atom is now ionized. The singlet oxygen is very reactive and reacts within picoseconds with an oxygen molecule to form ozone.
Ozone of course is the reason life exists on this planet. It blocks UV light below 320 nm. Anything below 320 nm is considered to be germicidial because the UV photon has enough energy to cross-link DNA, thus preventing cells from dividing and multiplying - that is the effect UV light has on bacteria and viruses when used for treating water and air - it crosslinks DNA.
Now when I meant ozone blocks UV light it actually absorbs a photon, and converts the ozone back to oxygen. Thus, the ozone layer is constantly being destroyed by sunlight, but also rejuvinated by sunlight. My theory on why the dinosaurs became extinct is that the ozone layer was disrupted by some unknown phenomena, thus all land dwelling creatures died off. However, water dwellers, such as sharks survived, because water absorbs or blocks UV light.
To answer your question, can VOCs be ionized? Yes, simply look up the ionization potential of the VOC. Find an irradiater that produces a sufficient amount of electromagnetic radiation at the ionization potential (wavelength) and you are ready to ionize your VOCs.
I have an Excel spreadsheet I created for several large chlor-alkali plants (produce chlorine and caustic soda). For example, diatomic chlorine will cleave with 247 kJ/mole of energy. That equates to a wavelength of less than 365nm. Now, it is known that this is a chain reaction. If you miscalulate the length of the chain reaction in combination with the actual pathlength of UV light through chlorine gas, then you will have nothing but a smoke and mirrors UV light reactor for removing nitrogen trichloride and hydrogen from wet chlorine gas.
If you would like additional information on removing VOCs please email me at:
toddforet@usa.net
I have several white papers and a very good presentation that was funded as a symposium/workshop by DOE as "Photochemistry for the Louisiana Chemical Industry."
Now, if you still want to ionize a sample of your exhaust stream, then I can loan you one of my plasma torches. Guaranteed to take your VOCs to an ionized state - plasma. The small 2 kW torch creates a steam plasma at a temperature of over 15,000 F. I will 100% guarantee that your VOCs will be ionized and then oxidized to CO2 and H2O at a gas speed of about Mach 3!
Sincerely,
Todd
toddforet@usa.net
A little information about ionization of VOCs. First, if you are going to ionize any VOC in an exhaust vent be ready to buy an extremely large generator - may I suggest a GE LM2500 gas turbine generator. In lieu of ionizing the VOCs, if your exhaust stream has a sufficient amount of oxygen, simply pipe it into the compressor of the gas turbine engine. A very cost efficient thermal oxidizer that generates electricity. If your vent gas has a concentration of VOCs that is above the LEL, the piped it into the exhaust of the gas turbine engine that is retrofitted with an afterburner!
Now with that being said, what is the source for the VOCs? Refinery vent gas, glycol recovery unit, paint booth, VCM oxi plant, etc.?
Here is a little information that may be helpful, but boring to read:
It is very possible to treat VOCs with a photocatalyst. But beware of the UV light source. Keep in mind that the reason VOCs are permitted is because of carcinagenic properties (benzene) and also because of the photocatalytic reaction between NOx, VOCs and sunlight (UV light at a wavelength of 365 nm). It produces smog, which is ozone. So can this reaction be controlled within a process stream. Absolutely. see my US patent #5,832,361 on USPTO website:
I noticed that Mr. Ctairman suggested the use of active oxygen. However, he did not suggest how you would produce the active oxygen. Active Oxygen is a misnomer for singlet oxygen. It is the first step that occurs when vacuum UV photons (185 nm and below) strike an oxygen molecule. The oxygen cleaves into two oxygen atoms with unpaired electrons. Thus, one could say that the oxygen atom is now ionized. The singlet oxygen is very reactive and reacts within picoseconds with an oxygen molecule to form ozone.
Ozone of course is the reason life exists on this planet. It blocks UV light below 320 nm. Anything below 320 nm is considered to be germicidial because the UV photon has enough energy to cross-link DNA, thus preventing cells from dividing and multiplying - that is the effect UV light has on bacteria and viruses when used for treating water and air - it crosslinks DNA.
Now when I meant ozone blocks UV light it actually absorbs a photon, and converts the ozone back to oxygen. Thus, the ozone layer is constantly being destroyed by sunlight, but also rejuvinated by sunlight. My theory on why the dinosaurs became extinct is that the ozone layer was disrupted by some unknown phenomena, thus all land dwelling creatures died off. However, water dwellers, such as sharks survived, because water absorbs or blocks UV light.
To answer your question, can VOCs be ionized? Yes, simply look up the ionization potential of the VOC. Find an irradiater that produces a sufficient amount of electromagnetic radiation at the ionization potential (wavelength) and you are ready to ionize your VOCs.
I have an Excel spreadsheet I created for several large chlor-alkali plants (produce chlorine and caustic soda). For example, diatomic chlorine will cleave with 247 kJ/mole of energy. That equates to a wavelength of less than 365nm. Now, it is known that this is a chain reaction. If you miscalulate the length of the chain reaction in combination with the actual pathlength of UV light through chlorine gas, then you will have nothing but a smoke and mirrors UV light reactor for removing nitrogen trichloride and hydrogen from wet chlorine gas.
If you would like additional information on removing VOCs please email me at:
toddforet@usa.net
I have several white papers and a very good presentation that was funded as a symposium/workshop by DOE as "Photochemistry for the Louisiana Chemical Industry."
Now, if you still want to ionize a sample of your exhaust stream, then I can loan you one of my plasma torches. Guaranteed to take your VOCs to an ionized state - plasma. The small 2 kW torch creates a steam plasma at a temperature of over 15,000 F. I will 100% guarantee that your VOCs will be ionized and then oxidized to CO2 and H2O at a gas speed of about Mach 3!
Sincerely,
Todd
toddforet@usa.net
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