N2 + H2O question:: incinerator/ scrubber
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Baghouse filters are used to capture particulate dusts (mostly metal fume) from effluent gases.
Dioxins and furans are going to be vapor chemicals and would be removed by either very high heat, chemical scrubbing, or perhaps ionic filtration (kind of like the ionic breeze). The latter two would require further processing.
Dioxins and furans are most typically the byproduct of incomplete thermal destruction of polychlorinated biphenyls (PCBs), but the combination of chemicals in mixed lots of circuit boards gives a mix sufficient for concern (especially the older you go).
Dioxins and furans are going to be vapor chemicals and would be removed by either very high heat, chemical scrubbing, or perhaps ionic filtration (kind of like the ionic breeze). The latter two would require further processing.
Dioxins and furans are most typically the byproduct of incomplete thermal destruction of polychlorinated biphenyls (PCBs), but the combination of chemicals in mixed lots of circuit boards gives a mix sufficient for concern (especially the older you go).
That unit appears to be designed (at least somewhat) for what you are intending. It appears this is added to an existing baghouse as a polishing step (only a cursory study performed). My only real concern is since you don't currently have any raw gas concentration data I would be concerned with initial studies to determine catalyst life / fouling and hence operating costs, but if you find a good stack testing consultant in your area they should be able to provide you with information on flue gas testing. It would appear you are on the right track with a unit like this though.
Thank you kjt, I am currently in communication with several folks, an engineer, the manufacturer, a furnace builder, mediburn, and a furnace company who designs and builds units for the industries . This last person is designing an after burner, Das is helping with the function of the Escape unit. The engineer will be calculating the stack flow and off gasses. The furnace builder is supplying parts and knowledge for the incinerator. Mediburn has sent me details of their units function and design. The afterburner designer stated just yesterday in our email, sometimes you need a wet caustic neutralizing stack, that's when I mentioned the Das unit to him. I think I'm on the right track.
It seems that not too many folks are willing to impart their wisdom on incinerating cleanly. I firmly believe the reason for this is $$. If one would understand the fundamentals of building such units and knew how to weld and understood electronics and plumbing, such a unit could be built for a fraction of the selling price of such units. By the time my design is complete, it would potentially cost many times more than I am willing to pay. Of course i will have engineering approvals and the associated fees, but my plan is to have a completely safe and stable exhaust stream with minimal waste and complete recovery and conversion.
Thank you for interest in my thread , I hope it finds you well. I will certainly post any advancements as they arise, Jonn.
It seems that not too many folks are willing to impart their wisdom on incinerating cleanly. I firmly believe the reason for this is $$. If one would understand the fundamentals of building such units and knew how to weld and understood electronics and plumbing, such a unit could be built for a fraction of the selling price of such units. By the time my design is complete, it would potentially cost many times more than I am willing to pay. Of course i will have engineering approvals and the associated fees, but my plan is to have a completely safe and stable exhaust stream with minimal waste and complete recovery and conversion.
Thank you for interest in my thread , I hope it finds you well. I will certainly post any advancements as they arise, Jonn.
I use to build and design afterburners for my aluminum sweat furnaces. I've dealt with some parts of what you are trying to do, but i still don't exactly have a good definition of what it is your trying to do. I'm still somewhat familiar with the EPA laws that govern this so to speak, but not totally up to date. Here's my first question. Have you contacted your state permitting authority to tell them what it is your trying to do? You may design and build this system only to find out that you didn't have to go through all the trouble you are or they could tell you it's not enough. They should be your very first contact before any design and planning stages of manufacturing. Different size processes qualify under different permits and what i mean by that is they have a small source permit (air) and a major source permit. Do you know which one you need to apply for. In your case it's probably going to be the minor source unless you are planning on running 24-7 and doing 50 tons a week. The small source permit is easy to obtain for the afterburner system. It requires a few pages of paperwork and probably a $1500/year permit fee or somewhere around that. And to tell the truth you don't need an engineering firm to design it. You can build one yourself if you have a little knowledge. The epa doesn't care who builds it and as far as i know being an engineer doesn't give you any special qualifications with the epa to build them. It's all about the machine parameters and not your education. The only requirements for the afterburner should be a .8 sec retention time at 1600 deg F. Their is two ways you have to prove this to the EPA. One is a calculation you use to figure air flow into the system through the burner or combination of burners with a thermal coefficient figured in. This will give you a volume rate. You then have to use that number for designing your afterburner so the air is slowed down which equals your retention time in the chamber so the thermal breakdown can take place. You will have to show this calculation on the air permit work sheet. Other than that calculation their is only one other thing that the EPA requires. That is a data logger with a thermal couple. It will record the afterburner temperature and store it in for record if the EPA ever wanted to look. Sort of like the patriot act requires us to record proper identification but not to report it unless ask to. Other than that the engineer is basically worthless if you have the knowledge yourself and after that you still need a fabricator to fab it up for you anyways. Then refractory, burners, and control systems.
Hi Palladium, thank you for your input. I know you have a lot more knowledge in these things than I . My original post was intended to determine whether or not the Das unit could be used for this industry. I consider the first step in ewaste refining to be incineration. It it also very important in other sourced material, sweeps, carpets just to name a few. If these items can be incinerated safely and turned to ash, the ash could be processed. I would be better at fabrication at this point and not so good at calculation. That's why im consulting with others more knowledgable than I. I can't pretend to calculate something I don't fully understand. I read your post twice and afterwards found the EPA requirements for afterburners, its called the Fact Sheet. I noticed in this fact sheet this sentence : For halogenated VOC streams 1100c (2000f) combustion temperature, 1.0 second retention time, And use of an acid gas scrubber on the outlet is recommended. Since the Das has both, I would think it should work. As a matter of fact, I thought that would be best before even reading the EPA fact sheet. I just now found this fact sheet. Now, you mention a data logger and thermocouple, great. The Das has both. Here's the basic idea, an incinerator loaded with about 50 lbs maximum of metal bearing parts. A blower on one side to introduce oxygen. The other side we will call the outlet. The outlet would feed into the Das. The Das has an afterburner with a dome to direct any solids back down into the holding tank. Above this dome is a scrubber and wiper system that sprays a solution of NAOH and water.This water solution neutralizes, cools, and directs the solids into a tank. If you could help me understand this and get this working, that would be great. if you are interested in helping me , please send me a PM.Thanks, Jonn.
