Thermal Oxidizer Basics Webinar
at CECO Environmental we're proud to be your single source for pollution control it's our mission to protect our shared environment and we relentlessly pursue that goal by providing reliable products and services to tackle your environmental challenges purchasing pollution control equipment can be a complicated process particularly when you have a system that requires many different pieces of equipment however our vast range of technologies and solutions for pollution control and product recovery can eliminate that complexity lowering your total cost of ownership without sacrificing performance across a wide variety of industries CECO helps ensure you achieve real results no matter your need CECO has you covered simplify your environmental initiatives with our CECO Environmental family of industrial solutions brands CECO Environmental is a global leader in air quality and fluid handling serving the energy industrial and other niche markets through Innovative technology and application expertise CECO helps you grow your business with safe clean and more efficient solutions that help protect our shared environment we work tirelessly to improve air quality optimize the energy value chain and provide custom engineered solutions for applications including oil and gas power generation Water and Wastewater battery production polysilicone fabrication chemical and petrochemical processing and more to learn more visit secoenviro.com today oh welcome and thank you for joining us today for the Seacoast certified Continuum education Series today we will be learning about thermal oxidizer Basics presented by CECO environmental my name is Mary Rusnak and I'm the Marketing Manager for the industrial air and fluid solutions segment of CECO and with me today is Brian Cannon our VPS sales and marketing for CECO Ad West and Brendan Budelier oxidizer applications and project engineer while we wait for everyone to join I'd like to go over some basic housekeeping items about our webinar platforms and also about the pdh certification first things first sound issues so first thing check your media player which is on the bottom make sure that you're not muted and that it's working properly there's also a help widget there blue arrow will show you a little question mark and that will help you with any other problems that you may have finally if you continue to have issues try logging out and logging back in using the link from the email when you registered platform itself at the bottom of your screen are multiple application engagement tools or as I like to call them widgets that you can use all the widgets are resizable and movable so feel free to move them around and just you know do what you need to do to get the most out of your desktop space you can expand your slide area to maximize it to full screen or just make it smaller whatever the case you want to do just by using the arrows in the top right corner if you have any questions during the webcast you can submit them through the QA widget which is a little question mark there to keep ourselves on track all questions will be held until the end of the presentation but you can submit your questions at any time if we don't get your question live we will definitely contact you later and get you the answer that you're looking for a copy of today's today's slide deck and additional help materials are available in the resource list there on the right we encourage you to download any resources or links that you may find useful you'll find all of our links to LinkedIn, Facebook, YouTube and just for future reference we do post all of our events on LinkedIn and Facebook so you can always keep an eye on upcoming events that way the oxidizer summary that's over on the right hand side is something that would be very useful for anybody who is taking the quiz later and might need a little bit of maybe help uh professional development hours or the pdh state information is also listed over to the right we are able to offer pdh credits for professional engineers for 36 states right now if you hover over any of the widgets it'll basically tell you what they are so there's a lot of options you can share via social you can email me directly from the widgets on the bottom and then the two more important ones are the checks Mark which will take you to cecocertified.com that's where you can sign up for more events or also take a look at the on-demand archive for the webinars that we've already had this year and we also have one additional webinar that will be happening on November 18th and that is industrial ventilation design so feel free to go over to cecocertified.com to sign up for that or for any of our on-demand versions now if you're here for the pdh portion the two Labs widgets are probably the ones you're going to want to look for at the end the test and cracker widget the test is where you basically take the quiz and the tracker widget the one on the very end is where you check your progress once you have filled all the requirements you will actually get a little box that pops up that you can basically print out your certificate from there an on-demand version of the webcast will be available after the event and can be accessed using the same audience link that was sent to you earlier and all of the interactivity remains including testing capabilities so if you get accidentally booted off don't worry about it you can come back on and print everything out or you can come back later and take the test if you run out of time and can't do it today so quick overview of the pdh portion today's webinar is worth one professional development hour you need to be here for at least 50 minutes this is both worthy live and on-demand version as I mentioned if you get interrupted you can just log back in and continue you must complete and pass the test which is basically getting 8 out of 10 right once you fulfill all those those requirements you'll be able to print your certificate out of that certification widget suggest that you guys keep a log of this week no we'll keep records for six years if you have any questions related to any of this feel free to just email me directly that's my email and let's take a look here and just again and also the webinar is one hour long but just so everybody's aware we will keep platform open for an additional 30 minutes afterwards so that you can finish up your test print out anything that you want so in terms of the outline these are the things that we are going to cover here today definition and overview we're going to look at the three T's what does that mean oxidizer components what are the different types that you would use and where basically some design and process considerations and then a little bit of examples at the end to get you an idea of how these are used and we're going to start today's webinar with a poll question and if you've attended our events in the past you'll know that you will be able to answer the poll in the next slide so starting off here with our little bit of our Halloween theme poll question how much experience do you have with thermal oxidizers and VOC controls and there's your options there you're an expert I have some experience I have a little bit of experience in what in the world is an oxidizer I'm going to advance the screen here and this is where you can put your answers hey give me a second here just to finish up your answers we'll take a look at the results okay that's a nice variety of experience that we have there looks like at the majority at this point have a little bit of experience some are really new into the experience itself and what an oxidizer is and then we have a couple experts in there I think this is going to be a great presentation for all of you even if you're you know an expert there's a lot of information in here as well as some things that that'll definitely help guide you in terms of a selection and the process in any future needs that you have so I'm going to turn this over to Brian Cannon so it's going to actually start to see real presentation itself with all the info Brian many thanks Mary hopefully everybody can hear me well I will say good morning a good afternoon and a good evening to all our attendees here for the webinar we have attendees I believe from all over the world and probably just about all the time zones so we certainly appreciate your time I hope this webinar we find everybody safe and healthy as well and he's trying times for the pandemic So today we're going to be covering a wide range of thermal oxidizer Basics we're going to be probably hitting the tops of a lot of waves and outlining a lot of the various thermal oxidizer and and sometimes they were called many years ago fume incinerator Technologies and solutions that are available we're you know and if you look at this what really demands or what is the driver for why anyone would want to use a thermal oxidizer and this slide here is really sort of a timeline at least here in the United States we've been fairly Progressive through the decades on air pollution control as well as on VOC abatement and a lot of our federal legislation didn't start until the 50s here in the United States so a lot of this is just fairly recent in the last you know 50 to 70 years these these stringent guidelines and they've spread throughout the globe I first started in thermal oxidizers back and fume incinerators is when they were called back in 1977. we've gotten sophisticated in the 80s with calling them Thermal oxidizers and then we saw a lot of the rtos really take over a lot of the recuperative and afterburner applications but the drivers here are the various legislation acts at least here in the states I know there's a lot of countries that have emulated the U.S EPA the
federal EPA clean air amendments titles one through five and obviously on title V that allows the various State epas here in the U.S to develop and enforce detailed industrial air permit programs and work with the various Industries plants and so forth but they've gradually gotten more stringent Through The Years there's been different amendments that have been specifically for various Industries for example there's there's a Max standards mac.t standards for the wood industry for the Composites industry paint finishing and so forth so we could go on with this and there could be all kinds of training on these Max standards and how to meet them and on title five we're gonna have to save that I think Mary for some later webinars the VOC go through just a couple real quick definitions here the the volatile organic compounds or vocs is we refer to them typically there are a lot of solvent fumes and Vapor phase gases they contain carbon they can have acids in them and a lot of these will have aldehyde type components lock the longer chain hydrocarbons and they cause noxious and toxic type fumes and smelly odors and typically these need to be broken down or abated or oxidized or incinerated and typically you know it's around 14 to 1500 degrees Fahrenheit and greater on thermal oxidizer Technologies we'll talk a little bit about catalytic oxidizers Brendan and I will do that here shortly and that's at a lower temperature similar to your catalytic converters in your cars but you know the the vocs are non-generally non-water soluble wet scrubbers are generally not a good application for these so if you have vocs you're probably pretty well looking at thermal oxidizers maybe a catalyst option you could be looking at Carbon systems and you could also be looking certainly at bile filters and we'll just touch on that option as well to give you a overview also the hazardous air pollutions pollutants or haps the the national Niche app on stationary sources obviously there's hazardous air pollutions and pollutants and those have to be dealt with as well they can cause cancer and carcinogenics and everything from skin rashes to nervous system damage and so forth so generally they can be wet scrubbed there's very few and some of those can be handled with a combination of both oxidizers and a scrubber on the tail end and we'll talk about those a little bit later so if you hear the word half that's hazardous air pollutants the niche app is the nationally emission standards for hazardous air pollutants probably the biggest definition and it's it's it's been time honored through the years is tried and true are the three T's sort of the basics of thermal oxidation or thermal incineration Technologies and how to break down these these hydrocarbons whether they be a longer chain hydrocarbon with lots of aldehydes or if it's a smaller type type compound but as I mentioned oxidation temperatures typically are 1300 degrees and greater most compounds you're going to see 14 1500 degrees sometimes 1600 degrees Fahrenheit a lot of oxidation systems will actually require greater than than that sometimes 18 to 2000 degrees 1800 to 2000 degrees if you get into pcbs and things like that the ability of a catalyst unit those typically will light off or activate at 550 degrees Fahrenheit to about 800 degrees Fahrenheit so catalyst is not applicable for all applications and all vocs you typically don't want to stay away from heavy metals from silicone laden compounds from acids heavy metals like lead Anthony and those types of things but catalysts can provide some energy efficiency because they use a lower temperature to activate on the Catalyst and the purification reaction there is not in a retention chamber but over the Catalyst we'll talk about that later the time element vocs can spend typically a half second up to two seconds or more retention time or residence time at these higher temperatures to ensure complete oxidation you basically bake the vocs at a certain temperature and you also do need turbulence in the combustion Chambers while you're doing the temperature and the turbulence comes from adequate mixing for the oxygen you want to have oxygen with the vocs typically you can have burners through on recuperative units or dftos through the burners there's mixing plates in a lot of cases with an RTO or regenerative thermal oxidizer you get mixing in the various media types could be turbulent flow through say saddle Media or laminar flow through block type Medias and we'll touch on that here a little bit later but typically you're going to need about 15 to 16 mole percent O2 for proper combustion you know with the various burners available in stoichiometric ratios and so forth so the the three T's all work together and we'll be talking about that throughout our presentation when to use a thermal oxidizer obviously you may have a title V permit if you're here in the United States obviously this is all VOC driven with the regulations from your various National epas or Ministry of environments or Department of Environmental Protections or the various States or even local here in the states the South Coast Air Quality Management District that almost takes Preston over everything in the state in the lower part of California and you have the Bay Area up top as well they work with the California air resources board and US EPA so so basically no no what you're under as far as regulation with the regulators the regulators are your friends they're trying to accomplish compliance and they want you to do it in a cost-effective manner well if you have odors or reactive gases you're going to need a thermal oxidizer at higher temperatures there a lot of times you'll see roaster fumes from coffee roasters and things like that have applied thermal oxidizers through the years actually afterburners to take care of the fumes and smoke but there's a lot of odiferous compounds you'll see in food processing rendering fragrance and perfume type manufacturing applications there are vocs and solvents in there and there are some longer change hydrocarbons on that the requirement for the high VOC destruction is typically done percentage by weight or volume um and the higher these VOC destruction efficiencies in most cases eliminate on a practical basis the use of bile filters across the board or carbon filters carbon filters have to be replaced and rejuvenated thermal oxidizers typically provide 95 to 99 plus VOC Dres you're looking typically on biofilters and carbons 80 to 90 percent on the VOC Dre they can get higher than that but you're going to need more surface area larger carbon beds or canisters larger bio filters some of these things can get as big as as almost a football field so you're going to need more surface area more resonance time inside the biofilter another another thing to consider if it looks like we have many experts and probably people that have older oxidizers that their plants here attending Mary but a lot of the older dftos the direct fired afterburners and recuperative units they typically use a lot more energy than rtos and rtos can be retrofitted on them to achieve higher destruction VOC or equal high high VOC destruction and they can also reduce these to oxy missions and also the energy usage which is key because energy costs are only going to go up in the future there's many choices of thermal oxidizer so I mentioned we have the direct fired also called afterburners you can get these in a horizontal or vertical fire type Arrangement there's the recupative thermal oxidizer that would typically use a shell and Tube or plate and frame type heat exchanger to recuperate and reduce energy typically those are about 35 to 80 percent thermal efficiencies the RTO thermal oxidizers those are between 90 to 97 thermal efficiency we see that as being one of the more flexible Technologies you can also have an rtco option you can have the RTO operating with a catalyst bed at the top at lower temperatures and we see that a lot in the wood industry there's flameless versus burner fired RTO options most of these systems can be done we've seen and have done rtos ourselves in both electric heat and burner and there's also catalytic units out there that operate electrically and also have burners and typically a lot of Industries will will call these fume incinerators if you have especially High VOC concentration flow rates or concentrators are used there for high flow rates and low volumetric Inlet loadings and usually it'll put a small dfto or small oxidizer or some some type there typically you're going to see that in the paint industry in Composites in several of those types of Industries we have the the zeolite rotor module concentrators we're just going to touch on these today we could probably do a webinar on these as well Mary typically the concentrator media of choice is a zeolite rotor module hydrophobic zeolite and it's a typically a honeycomb structured absorbent it absorbs the vocs and then it's desorbed you'll typically see 10 to 1 and greater VOC concentration ratios so see if you had a hundred thousand CFM paint line you could put a concentrator and typically if you're a 10 to 1 concentration ratio you'd have about a 10 000 scfm smaller oxidizer on the tail end so your Capital cost lowers and your energy costs are significantly lowered through that ten thousand scfm oxidizer as opposed to having a large hundred thousand CFM RTO and of course you'll typically see those the paint industry semiconductor Fab Composites and just general spray coating low inlet temperatures they don't like acids the concentrators can be very finicky so it's they're not applied to all applications thermal oxidizer types the three major types that we see besides the direct fire typically the RTO has been the most flexible through the last probably two decades three decades the regenerative thermal oxidizer regenerates various beds typically two to nine or eleven beds depending on the design and you can get between 85 and 97 percent primary heat recovery and you get good mixing through these ceramic media and there's a couple pictures there in the middle showing some ceramic media some black Medias they typically look like catalytic converters in your car and you can see some ceramic saddles on the lower left the recuperative oxidizers use a shell and Tube or plate and frame heat exchanger the upper left shows a shell and Tube I think those are inch and a half round stainless steel tubes those have Expansion Joints with the various bundles to prevent leakage to get you the high destruction efficiency you will get some expansion and contraction if not done right you can get some leakage and that will deteriorate your VOC destruction over time so you want to definitely pick a good system has good expansion and good leakage control and good welding on that a catalytic oxidizer typically will use a catalyst bed and that's going to be about 550 degrees Fahrenheit to 800 Degrees and those are sensitive to silicones heavy metals sulfur compounds if you have those in the Stream probably not a good application so know your application know what's in there with your solvent inventories and so forth typical applications and probably most of you are familiar that have some experience everything from semiconductor wafer Fab to paint spray and finishing coating of everything from cars automotive components Wood Finishing could be wood furniture bowling pins we've seen applications there coating bowling pins and just about everything that's used as on a solvent coating the food industry we see a lot of everything from fat fryers to rendering facilities fiberglass and carbon fiber as as a lot of Automotive components and just everything is switching from steel and aluminum over to carbon fiber and fiberglass it gives you added strength added flexibility but you also have styrene and other types of vocs and those processes that need to be abated refining and petrochemical and pharmaceutical that's always been a strong industry and then everything from soil remediation to small units Bakery ovens and even metal and Automotive recycling has applied oxidizers for those types of applications for VOC control again a lot of the process applications and it's a wider range when I first started I never thought we would see for metal shredding we would never see oxidizers applied to that so the tried and true ones are obviously you know web converting chemical processing wood products and veneer dryers resins MDF plywood plants pharmaceutical reactors and spray dryers and then we're seeing a lot of streams these days that certainly have acid gases and halogens that have to be addressed as well with alloy design and Brennan will be talking about that a little bit and we can have scrubber options there so there's there's quite a bit with all these various processes I think we're at a poll question here Mary so I'll take it over let it take over here thank you Brian thanks for that great overview hey we're up to our next poll question again don't forget you'll be able to put your answer in the next slide so what type of thermal oxidizer are you most familiar with and you can choose as many as you want so dfto recuperative thermal RTO rco lots and lots of initials here right macronyms dfco for direct fired catalytic oxidizer or something else so let's put you to the next slide and remember you can choose as many as you want and since this is a little bit longer question we'll give you a couple more seconds to fill everything out all right just let everyone finish up and we will take a look at these results and see what what everyone's familiar with I guess not surprising here that the RTO is the one that most people have definitely seen out there but it seems like we've had a good mix here in terms of other oxidizers that are out there so nice mix out there in terms of what people are familiar with and we're going to now pass this on over to Brendan who's going to talk a little bit more about different components in that absolutely thank you Marion Ryan yeah that that the poll results make sense I would say not surprising that the regenerative oxidizer is the most common but I'm glad to see that we have a diverse group uh familiarity all around it seems so yeah before I get into more of the technical aspects thank you for joining again I just want to sort of brush over the you know reiterate rather the working concept behind any thermal oxidizer and it's really that you have a given flow rate of gas right it has particular characteristics you know it may it has a humidity it may have uh particulate matter but certainly has vocs and haps uh you know speciation but at the end of the day it's a given volume of gas and it needs to be heated to a certain time a certain temperature for a certain amount of time around a second so really you have a flow rate and it needs heat input to reach a certain temperature and the way that the oxidize is primarily differ is in the way that they manage the energy input and that primarily affects you know the Energy Efficiency the fuel efficiency and at the end of the day the operational cost of the unit so again while there are many different types of oxidizers as Brian has alluded to we'll get into these in more detail just want to reiterate to the purpose the fundamental operating method of all the different configurations is ultimately the same that is the oxidized vocs by the means of the three T's and demonstrating turbulence so there are certain components therefore that are going to be incorporated into any thermal oxidizer system essentially no matter the design we have a processed fan to move the gaseous vocs through the oxidizer this could be at the front end called Force draft and or the tail end Deuce draft you know typical industrial ventilation stuff there's an oxidizer casing generally you know it could be a mild steel or a stainless steel or any number of Alloys this serves as the combustion chamber the basis of the combustion chamber and you have a burner or some other heat source oftentimes it's usually a natural gas or a propane burner it could be an electric heater element as well you know anywhere where you can you can provide heat to the system and you have internal insulation to the Shell most common Steels you know they don't like to sit over 1600 degrees F continuously additionally that would definitely pose a risk and I don't think OSHA would approve certainly so generally the outer skin temperature needs to be managed below about 140 degrees Fahrenheit so yeah you know it's all insulated internally you have instrumentation and control Hardware to maintain the temperature and flow through the oxidizer additionally to shut down the unit if you lose fuel pressure you know compressed air pressure you lose the process anything and then finally you know you have some sort of an outlet an exhaust deck you can measure vocs otherwise you may be feeding into another you know prostate equipment like a tower scrubber for post-true kind of acid gases for example but anyway nowadays you know the RTO for gender of thermlock has one of the most probably the most common of all which also has heat recovery beds to minimize fuel usage that's a really important part of the way that it operates so that's the most common that you'll see so just before getting into the different oxidizes the more detail I want to direct your attention to this graph so this shows energy usage and million BTUs per hour it's a common common unit used for four different oxidizers but they're all ten thousand sefm and we're assuming zero via Seas and it's important again to note vocs are simply vocs versus your fuel source the DLCs are a fuel source so whatever you heat you don't add to the system in vocs you have to make up with your fuel if you have a lot of vses you know you don't need to add as much fuel because essentially you're just maintaining a flow rate a system at a certain temperature so you can see the difference that fuel efficiency is is vast this is directly result of the heat recovery capabilities of each of the oxidizers so the RTO on the the far right is the best but this also it plays into the applicability for a given process so oxidizes that require a large amount of heat to to stay up to temperature that would be a dfto or like a recoup on the left because they release a lot of heat so they require a lot of heat input they can also accommodate very high VOC concentrations you remember that a boc is a fuel source in itself it releases heat upon oxidation you find that the RTO where it excels you know in very low fuel consumption when running on on you know process around fresh air even it's somewhat limited to processes that don't exceed four to six percent LEL if you don't provide provisioning for that so if you say you know the oxidizer requires less than a million BTUs an hour in this case to hold its temperature or your VOC Spike to 1.5 million over time it you know continuously the oxidizer will overheat now there's things you do you include a hot gas bypass to remove heat from the system you actually derate the RTO and this is ultimately why the RTO is the most popular and flexible design anyway we'll get into that I just wanted to make the link that you kind of fuel efficiency and that goes hand in hand it's inversely proportional to the capacity to process ivoc concentrations all else being equal anyway hopefully this will make make sense as we move along so moving into the different types uh we start with the most basic kind of work our way up so the way I want you to think about this is there's kind of two general configurations for oxidizers you have a straight through design it's kind of a steady state straight through and then you have the regenerative design which is kind of to the side it's kind of its own thing the first few we look at will be straight through design which means you have air moving in One Direction You Know unmanipulated by any sort of flow control mechanisms other than the fans pushing it so here this is this is called the dfdo the direct fire thermal oxidizer pretty much is what it sounds like you have a metallic you know usually metallic internally insulated chamber with a burner plumbed into it this holds the combustion chamber at a constant temperature around 69 degrees Fahrenheit let's say then have a processed fan driving VLC Laden air through the unit and it exhausts through the stack so this is the simpler oxidizer it also uses the most amount of energy because you're you're simply heating up a particular you know flow rate of gas to a temperature and then you're exhausting it into the atmosphere without recovering any of that that energy that heat so it's typically used on Lower flow you know that would be lower operational costs lower flow applications where the process is running batches it's easy to you know shut it down and start it off basically just a burner and the Box heats up really quickly it's good for high LEL processes up to about 50 LEL I'm a sea control for it you can do up to 50 because it requires so much heat for the combustion chamber to stay at temperature again because you're just you're releasing all that heat so generally all these these straight through sort of type of oxidizers we're talking about can achieve over 99 VOC destruction if they're designed with adequate retention time that's always kind of a lever you know to play with uh moving forward a little more complicated the recuperative thermal oxidizer this is essentially a souped-up dfto it has all the same components only now you have a bit of heat recovery in the form of a single or multi-pass is usually shown through heat exchanger so what this does is preheat the process air using the hot combustion chamber air recovering anywhere from 30 up to 80 percent of the total heat of a system in a really efficient system in this case in case of this image the four parallel arrows here it kind of indicate the flow path through the four pass heat exchanger you can see it goes back and forth this substantially reduces the fuel usage as if you recall from that graph earlier but it is you know significantly more expensive than the dfto because you have the tubes tube sheets the costly internal high temperature Expansion Joints make sure everything's happy at high temperature as well as you know an ambient temperature when it cools down so this is really it's kind of the evolution of the dfto it's definitely been hugely popular in the past but for the most part kind of a replaced by the RTO the regenerative type you know just generally speaking moving on to another variation this we have a catalytic oxidizer this is kind of just to to showcase the Catalyst portion this is a catalytic recuperative oxidizer so again it has that that four pass heat exchanger but here we have a precious metal Catalyst bed kind of resides in the combustion chamber it's circled in the red there this allows for a bit lower oxidation temperature around 550 to 800 Degrees as Brian said rather than like 15 or 1600 degrees but it does require custom tailing for the process it doesn't work for certain things halogenated sulfonated heavy metals things like that so so you need to make sure it's you know compatible essentially but you know what you get for for operating at a lower combustion temperature is that you don't have to input as much heat it's more fuel efficient rather than operating it you know eating 5000 CFM to 1500 degrees you have to eat it too 700 so finally I'm going to move on to the the bread and butter the regenerative thermal oxidizer the RTO you know and or love or at least hopefully heard about generally speaking is most popular it can be the most flexible type of oxidizer available today there's many different types of designs of an RTO but this design has heat recovery like the recouper of oxidizer but it operates a bit differently from those straight through designs and that this recovers heat on a cyclical basis and therefore it is a lot more thermally efficient they can achieve up to 97 thermal efficiency generally and they come in a wide variety of one two three up to 12 plus he could have as many as you want essentially beds and can be designed to accommodate very high high LEL thirty percent think thirty percent LEL if you know what LEL means I don't know if we explained that earlier lower explosive limit it's essentially a indicator of the concentration of the vocs that you have in your Stream So 100 LEL would mean that you're at the leanest point in which when an explosion would would automatically Auto ignition would occur so typically you need to stay below 50 for any thermal oxide and there's there's many options for these that will that we'll go into as well but first I want to talk a little more about just how the RTO works so this is a typical two bed RTO kind of the easiest to explain and then the rest are all variations of this so so on the right here um so the two bed RTO recovers he'd be a two ceramic media beds processors brought in below one of the media Beds which preheats the air before entering the combustion chamber that's number five here then it goes down into the second bed which then recovers heat from the air so again the process is preheated goes through combustion chamber at about 15 1600 degrees for a fraction of second around a second that exits through the second bed which removes heat from the process so for a given cycle for the RTO the inlet side media bed starts off very hot and is cooled down by the incoming process error it's at the same time the out the outlet media bed starts out cool and is heated by the air that just came through the combustion chamber so the peps for the beds kind of act like a teeter-totter sea soft depending on where you come from where one is one bed cools the other is heated once the beds are at their respective kind of temperature extremes a few hundred degrees apart your flow control device whatever that is in the case of this image it's a it's the number is two here it's a poppet valve mechanism the flow control device will switch and reverse flow through the whole system and the process starts all over again and then your outlet bed becomes your Inlet bed which is which is hot and then your process absorbs heat from that so this results in really extremely high thermal recovery really it does require a split second of flow reversing which in the case of this too bad allows vocs to actually bypass the combustion chamber for that Split Second Escape through it straight through the stack so if you see one you have their processed fan and then for a split second while these two valves it points to are switching the process essentially goes from that bottom duct up to the top duck and out the stack for about a half second this is why in part the RTO is typically rated at a minimum to 98 destruction efficiency but there are things you can do to to capture or and or mitigate that puff entirely so that it's over 99 effective like the other straight through designs but anyway I want to reiterate you know say you have ambient air coming into this thing generally coming out for a 95 efficient thermal oxidizer the exhaust temperature will only be 30 to 50 degrees higher than the inlet temperature so you may have 70 degrees going in and 120 decrees coming out so that just kind of shows you how thermally efficient these are when you have the combustion chamber in the middle of all of it at 1500 degrees you're really recovering a large portion of that and that's why you know that's why they're the norm and that's why that's why yeah they're great so excuse me which slide is next yeah so the different oxidizer RTO types I should say for the regenerative oxidizer we have the the two bed on the right it's generally a little bit more cost effective it's for lower flow rates generally speaking compared to the larger they tend to be larger multi-chamer rtos the two chamber is kind of limited to what what you can shift easily so generally 80 90 000 scfm and it's generally standard rated at 98 destruction in terms of the multi-tower if it's a if it's an odd number designed to three five seven Etc that work similarly except for there's an additional media bed which is constantly in Purge so essentially you don't have that boc puff every time you have you have the bed being purse the lower all the vocs are being taken out of that Purge bed at a low rate and then that bed moves to outlet at the beginning of every cycle so that there is no VOC puff it will just go all fields use of the oxidized before exiting the unit so anywho it's a little more tends to be more expensive tends to be higher flow rate but you know you can definitely do a smaller multi-chamber RQ as well additionally you have the rotary valve rtos typically there's there's many different configurations but it could be a kind of a cylinder that from a from a plan view it kind of looks like a a pizza pie with with triangles cutting it and you have Inlet outlet and Purge sections very similar to any other three chamber but the whole the whole system kind of rotates on an axis so an interesting time keep moving forward here so again just reviewing factors that influence destruction efficiency we have the three T's retention time temperature and turbulence but additionally I added here the VOC puff particularly for the two chamber quick quick retention time calc is just it's the volume in the combustion chamber divided by the the actual you know flow rate through the combustion chamber at that high temperature yeah so now talking a little bit more about that VOC Puff I think I mentioned the puff capture module for a two chamber effectively makes a two chamber act similarly to a multi a three chamber or a five chamber with a purge bed but it doesn't you don't need an entire new not bad for the RTO so it's this additional enclosure and I think a little there we go that red circle that additional box in the back the additional pop-up valve it captures that one second of voc puff generally sized to capture a few seconds umto ensure you know 100 capture efficiency but if it then reroutes that that doc puffed back to the inlet of the unit during that cycle where it's oxidized so here we have an example hopefully this kind of helps those who who like seeing grass so so we have the difference between a two chamber standard two chamber on the left and a three chamber or a you could say a two chamber with a puff box on the right so the the yellow line indicates VOC Inlet in concentration and the blue line indicates the outlet so for the most of the time you know you could think of Destruction efficiency as one minus the area under the blue curve divided by the area under the yellow curve those spikes you see in the blue are the VOC Puffs so every four minutes give or take depending on how you set it up you have a VOC Spike in the case of the three chamber or the two chamber with puff capture box you eliminate that Spike and you oxidize close to 100 and so that's where that's where you can get those really high destruction efficiencies if it's required additionally really important really cool feature it's kind of a simple solution but works really well I was explaining how the RTO requires very little heat to stay at temperature right but in the case if you have a lot of process vocs or if you have a very variable process where you have maybe a little VOC at the time at a time but you have a lot you have some spikes but you have to operate the oxidizer all the time you would want to install podcast bypass essentially derates the thermal recovery of the unit there's a refractory line damper in the combustion chamber somewhere it routes to the exhaust stack or the exhaust manifold and it pulls hot air out of the unit so this allows you to operate at very high lels with RTO and anytime you're operating in this Zone you know the RTO has enough heat to get by what you're saying is that you know I need to expel some and you can essentially modulate this damper to maintain that 1600 degrees in the combustion chamber and you don't you don't have to use any natural gas or propane at all so it's it's a great way to to be if you can make your process work for you like that all you got to do is push air through it with your fan additionally we talked a little about flow control that's a really crucial part of the multi-chamber or the regenerative thermal oxidizer so there's different ways to do it you have the poppet valve or a standard butterfly valve you can see on the bottom right is a large unit with butterfly valves exhaust manifold on the right Inlet on the left side on the bottom there but these can all be you know pneumatic hydraulic electrical I mean pretty much you name it Additionally the rotary valve same thing it generally requires a purge air fan to to kind of block and bleed in a way that the seal all around the entire valve so but but it works you have air coming in through the bottom generally it goes up into the combustion chamber and then down again so it works like any any other thermal oxidative or RKO I should say once again just to review the options I kind of talked about a few but the the puff capture module or the the third Tower RTO these are great for you know odor problems if you need to you know sometimes a couple PPM is enough to set off the human nose so that's always an option Catalyst options you can incorporate a catalyst into an RTO as well as a recuperative unit or a direct fired unit again it just essentially lowers the temperature which that you need in order for for full oxidation instrumentation you know there's all sorts of options with the data collection and the last one division two you know explosion proof equipment metallurgies for acid gas applications you know stainless steel re2205 duplex you know a whole host of options Linux burners is very popular it really depends on what state you're in let's see but lately it seems you know most oxidizers are requiring them and then finally we do have secondary energy recovery for the RTO because the RTO is so energy efficient a lot of times there's just not much you can get out of the exhaust and RTO because it's kind of been cooled down by the internal system of it but on other thermal oxidizers it's it's it's definitely been used a lot so I'm going to hand it back over to Brian just for a second here to talk about secondary heat recovery options thanks Brendan great job obviously any oxidizer especially like the dfto when you have a very high stack temperature if you're coming in at ambient and going out at 1500 degrees on a dfto you have a lot of BTUs going up the stack and I know particularly in in Europe and even in Asia energy costs are a lot higher than here in the States but most customers today do look at secondary energy recovery it could be as simple as an air liquid heat exchanger like a hot oil or glycol or even air to water in the stack a little coil Chiller condensers we see out west in arid climates that makes sense for both AC air conditioning as well as chilled water you'll see that a lot in the printing industry the picture on the left the very top of the unit just below the stack the big box that's a chiller condenser system a secondary system that was put on that RTO and that customer had a lot of need for both AC and shield water in the plant in the process some customers may think that they will need a future secondary heat exchanger we can design up a provision in there I think most rtos can be designed for that to have a spool piece or whatever and also if you need to bypass the secondary heat exchanger a lot of times you may not need all that heat for Implant heating on air-to-air in the winter so you can bypass that so you need to think of all those things to design into your secondary heat recovery section and module here in the states I know in Europe there are potential utility Energy rebates for being very cost efficient and energy efficient and you always want to consider what your current energy costs are because they're only probably going to go up from from here so if you're going to have this RTO round for or an oxidizer or dfto for 10 20 30 years think of your future energy costs and try to minimize those that's very very important so I guess Mary we at the poll question here for you here had to yeah we're at our last question here thank you Brendan and Brian and hopefully you guys are not confused but if you are just remember you can shoot us a question and even if we don't get it to it during this presentation we will definitely get back out to you and make sure that it's answered so what type of thermal oxidizer if any do you have installed at your facility and there's a couple options there dfto catalytic oxidizer to bed RTO multi-tower RTO and as some of you may have seen I only have a VOC Destroyer license plate that's probably what I have I think that's my answer but there you go please place your answer here and we'll take a look at the results we'll give everybody a couple seconds here there are no wrong answers right Mary correct it's one of those easy questions for the day no wrong answers that's right all right let's see what we've got in terms of our results okay so we are looking at a majority here have a two bed RTO hey look at all those people who have the VOC Destroyer license plate that's awesome so then we also have just a catalytic oxidizer and the bfto are almost in the same percentage area so not too many out there that have three or more towers absolutely thank you for that so to kind of review here before we get into some examples thermal oxidizer dues we decided we're gonna we're gonna be optimistic here and just focus on what you should do so besides the oxidizer for maximum and minimum flow you know bracketing process data this is really important I'm one of the you know the worst things you could do is to just undersize the unit you know it's a it's a major capital expenditure and essentially there's not a lot you can do you know be other than redesigning the whole thing or putting in an additional oxidizer it's important to to accommodate or you know think about what what the minimum and absolute maximum blower you're going to see again the same goes for temperatures and VOC loadings you don't want to you know install an oxidizer and then find that it's kind of starting to overheat depending on how you run your process different times when you you know there's there's plenty of options to to be able to accommodate High VOC loadings again you need to consider your metallurgies It's always important sometimes you know if you have some sort of a sulfinated compound it may not be very reactive in itself you know the oxidizer kind of likes to create it likes to break things down and it also the byproduct of thermal oxidation is water and it's CO2 right so a lot of those halogens like to react with water and create acid gases so certainly need to consider that and that's something that you know thermal oxidizer provider should be able to look at and tell you what metal energy to go to again you know future expansion this kind of goes with number one but you definitely want to be thinking long term locating the oxidizer close to process also can be surprisingly important if possible or you may need to you need to manage at least the temperature of the duct so you have a you know process going on at 100 degrees but you have a large a long line of duct going to the oxidizer and that gives the opportunity to cool down the process a bit and condense some of those some of those compounds it can pose an issue for the process ban for the oxidizer as well but again yeah energy costs and plant expansion you know I think what what Brian and myself you know are trying to stress is that these things you know good one the last you know 20 years or more so you really want to consider what you know what's the what's the best option in the long term in terms of you know if you if you're going to need a slightly larger one a couple years from now additionally you know how much money are you going to save by getting a little bit of additional heat recovery right now it can really add up substantially so yeah there's there's a lot to consider but generally if you stick to these dues you don't even have to have to worry about the don'ts and moving forward I guess we have a number of installations here the last few minutes Brian and I will kind of run through these yeah we have quite a few here and and at the Sega time we'll probably go through some of these fairly quickly but I know like Mary said this will be on the website here the SQL certified website so you can always come back and look at these we'll have a bunch for rtos including multi-tower units two three seven chamber there's a in the upper right there's a three Tower as well as a five tower out of stainless and then there's two small two chamber units in the upper left so we'll try to get through these very quickly and then show you some examples of the dftos the direct fired and the recuperative units recruitive uses of course the Sean tubes typically heat exchangers in the lower left there's a DF to In The Middle on the lower part there's a almost a flare stack dfto a vertical one with tangential burner firing in the upper left recupative is in the upper right and that has secondary heat recovery on it and oxidizers even if you have small Point sources they can be mounted on trailers we and a lot of other people have done smaller units for soil remediation as you can see on the trailers between 500 and in 2000 CFM you can mount typically on trailers on the lower right we'll give you some quick examples here's three units here three two chamber units in Korea at a chemical intermediates plant typically what they're doing there is acrylonitrile and polymers is a force draft system there's redundant fans on each of the three rtos two of the rtos share common stack the customer wanted this designed in but you can see there's a collection system with the duct 95 heat recovery and these had turbulent flow saddle media another example here's two three Tower units sharing a common stack with induced draft fans this is on a spray coating and Metal Coating type application and there's also a concentrator system in the back of this there's typically alcohols and toluene that they're seeing on this type of application but again they went with induced draft fans on this application and the three chamber rtos are each 65 000 scfm so they have that dedicated Purge chamber that can alternate a structured black media these two are great examples of point source rtos installed this is actually installed on the roof of a client over in Taiwan and wafer Fab facility and semiconductor they put the larger unit in first and then built the stack to handle the second one when they added additional wafer Fab clean rooms those who have 97 heat recovery 99 I think 98 to 99 VOC Dre a very low profile very good for a rooftop Mount most of our applications and most of what you're going to see is typically ground Mount outside sometimes on a mezzanine sometimes in a courtyard is this case this is a five Tower 80 3000 CFM unit it was in a courtyard of a rubber processing plant very tight application they still had to have access for fire access for maintenance so this is a long long rectangular type top plan view here the system with the extra Purge is provided 99.3
percent consistent Dre says 2003. also I think as Brennan mentioned earlier you may need pre-filters on some applications there's carbon dust in this application tough application and rubber processing so know if your your application does have dust rtos will make great filters they really do but you don't want to change that filter media which is the ceramic media it can be expensive and time consuming so if you do need point source filters Upstream certainly do that here's a typical low profile unit again outside ground Mount this is on a web coding type application High solvent Hot Gas bypass because they can occasionally get up to 20 LEL and again just low profile so you want everything that's accessible pretty much from the grade here we'll try to wake you up a little bit with Halloween this is not a haunted RTO this is just a we've had some special effects with a nighttime shot of a roof mounted unit and a flexo printing and packaging plant and again this has multiple processes going into one Central RTO so they had individual fans pushing up from each process and this RTO does have an AC drive like most of our units have which you'll see I think with any RTO so it automatically will throttle back if you're only running one one press or if you're running all eight presses into the unit 99 destruction low profile which works out well for a rooftop application this is a typical rotary valve or indexing valve type RTO cylindrical type design with the media the burner is on top and the Dome this is a system that one of our our secret China Saudi group put in in China the indexing valve is on the lower portion and you can see that there's an access to it there's a separate Purge fan on that to keep positive pressure on the seals the valves there's basically no valve it's just that indexing valve at the bottom or we're indexing a device there's 12 heat recovery sectors if you looked at a top plan view so it looks like cutting a piece of pie or a piece of round pizza into 12 shapes so that gets 99 destruction and 95 heat recovery there's a low profile unit typically even in larger sizes is 70 000 CFM it's on a particular stream so there's reverse air dust collectors ahead of it it's on a Foundry casting line so you will get some sand dust that does carry through so formaldehydes Benzene alcohols that's typically what what this application is seen run and I'll let this over to you now with the cast and trader here I think that we probably are going to need to get ourselves to a couple questions here but just for everyone there are some additional examples here the PDF of the slides is available over to the right in that resources area so you can definitely take a look through the rest of the examples there and if you have any questions again shoot them off to us and we will definitely get back to you on them and I do want to thank Brendan and Brian for joining us today and doing this presentation and thank all of you for joining us we know your time is valuable we have let's try and do two questions here real fast and just a reminder to everybody you need to be here for at least 50 minutes of the presentation and you need to complete the quiz that's over on the right hand side let me show you the widget here so down here take a look at those last two widgets the second to last is where you test the last one is where you make sure tha
2023-03-26 17:25
