Low Temperature Air Drying Overview

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04/02/2025 Added

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Low Temperature Air Drying Overview by Robert Sunderland, Wenger Manufacturing, Inc. 2025 High Pressure Processing and Dehydration Workshop

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[00:00:00.000]A little bit about myself, I'm Robert Sunderland. I work with Wanger Manufacturing in Sabetha, Kansas,
[00:00:11.880]about 90 miles from here in Lincoln. Wanger is pretty well known in the world of extrusion,
[00:00:19.520]dry extrusion, high temperature, short time extrusion, human food applications, companion
[00:00:28.320]animals, a big part of what we do, some aquatic feed as well. Not only do we make extruders,
[00:00:34.080]but most processes that go through an extruder do need a drying step, and that's where I come
[00:00:40.080]in to the picture. I work in the drying division of Wanger, so Wanger is generally broken up to
[00:00:47.520]different classifications. Obviously, we have the commercial side and we have the engineering side.
[00:00:52.920]Wanger is kind of unique that we have a group of people that really just kind of interconnect,
[00:00:58.100]with commercial and engineering, and with our customers to try to decide what's the best way
[00:01:04.760]to tackle different projects. So my background is in serial science, a Kansas State graduate,
[00:01:11.860]along with a couple of my other colleagues. I didn't put that on the slide, I thought it might
[00:01:15.260]get scrubbed. So yeah, let's hop into here. Again, if we want, we can keep this very informal,
[00:01:23.580]nice small audience. So if you have questions, let's tackle them right then,
[00:01:30.420]or we could wait till the end. Basically, these are the highlights of what I hope to cover in
[00:01:37.080]this next hour or so, a little bit of who Wenger is and some industry trends that we're seeing.
[00:01:43.880]And again, a lot of this presentation is kind of built around the companion animal world,
[00:01:48.780]because that seems to be where we're getting most interest in these
[00:01:52.920]modest temperature drying applications. Then I thought we'd just kind of step back and kind of
[00:01:59.520]look at a cookie cutter, how's these dryers work, you know, component selection, what's our design
[00:02:04.380]mindset when we start putting these dryers together, and then maybe look at a couple of
[00:02:09.920]processes that are actually out there in operation, and then kind of looking at the new product and
[00:02:14.520]scale up. So again, a few bits about just who Wenger is. Again, we're about 90
[00:02:22.260]miles away, a family-owned organization for years and years. A couple of brothers
[00:02:26.400]in the 1930s started Wenger manufacturing in the feed industry, made
[00:02:32.340]pellet mills, made some conditioning for pellet mills. They've been based in
[00:02:37.520]Sabetha, Kansas, a town of all of 3,000 people. Their entire time, up until about
[00:02:43.440]five years ago, then when some acquisitions started happening, we're a
[00:02:47.520]family-owned organization that is very
[00:02:51.600]international. Generally about 60% of our sales, our deliverables, are outside of
[00:02:57.500]the U.S. So we touch a lot of places. I've traveled a lot in my career, been with
[00:03:03.480]Wenger for 30-some years. I think I've been to 44 countries so far. A lot of
[00:03:08.220]repeats on that list as well, but generally Wenger covers these three
[00:03:13.620]broad areas: human food, companion animal, pet food, and then the final
[00:03:20.940]is aquatic. And when we say aquatic, we're not making fish, we're making the
[00:03:25.860]food for the fish. So shrimp feed, salmon feed, catfish feed, these applications. So
[00:03:32.640]these are the three broad groups that we serve. Companion animal is a driving
[00:03:37.860]force behind Wenger. It probably accounts easily for over half of our annual
[00:03:42.840]turnover, so just a lot of equipment in companion animal and that normally has
[00:03:49.140]been dry expansion.
[00:03:50.280]Expanded pet food, so cereal grains mixed with proteins, extruded, passed onto a
[00:03:57.520]dryer, passed onto a cooling system. So again that is a big part of what we do.
[00:04:02.040]So we make extruders, single strews, very old-style, simplistic machine, get into
[00:04:10.040]some higher functioning twin screw machines, our dryers that we manufacture
[00:04:15.520]hot air again. So typically we are,
[00:04:19.620]when I say a cool or a warm air application for a dryer, 80 degrees C I
[00:04:26.120]would call fairly cool. 90 degrees C, 100, 150. We have some applications that touch
[00:04:33.060]up in that 180 degrees C. So we're not talking for three or four hours at these
[00:04:38.820]temperatures. Normally, you know, 20 minutes, 15 minutes, sometimes down to five
[00:04:44.760]minutes. So again, we're not as short time
[00:04:48.960]in our conveyor dryers as we are an extruder, but we are still pretty short
[00:04:55.260]time. So 15 minutes to 45 minutes catches most of our dryer applications. And again,
[00:05:03.720]we'll get into this that these are continuous type systems. Not, we don't, we
[00:05:08.280]don't produce, I don't have very much experience in in batch systems. So these
[00:05:14.080]are continuous dryers. So again, we have about 500 employees.
[00:05:18.300]Again, being such a worldwide foot area, we have offices in Europe, in Asia, in
[00:05:26.620]South America. We have manufacturing facilities in South America. Again, at
[00:05:31.740]least half of our equipment is made in in Sabetha, Kansas. So we have research
[00:05:37.920]facilities. Also, we have several facilities. Some, a small facility in Asia,
[00:05:44.240]in Korea. We have a facility in Brazil.
[00:05:47.640]Again, you'll see at the very end there's a parent company, Morrell. This is a bit
[00:05:53.240]dated because now we are JBT, Morrell. So we've grown and grown. We've gone from a
[00:05:59.540]company of 500 employees in Sabetha, Kansas and we were acquired by Morrell
[00:06:04.600]to 5,000 employees and now we're like 10,000 employees. So I'm still trying to
[00:06:09.280]get used to these large corporations. So again, pet food is a big part of what we
[00:06:16.120]do. A lot of this
[00:06:16.980]presentation is gonna touch on pet food and maybe a broad statement here but at
[00:06:23.820]least 70 maybe 75 percent of the pet food produced in the world is touched by
[00:06:29.100]Wenger equipment. Either Wenger extruders or Wenger dryers, Wenger coating
[00:06:33.660]systems, Wenger cooling systems. So we really have a pretty good pulse on
[00:06:38.100]what's happening in the companion animal world and again we have a large presence
[00:06:42.420]in R&D. This is our R&D facility in
[00:06:46.320]Sabatha again just like an hour and a half down the road. We have like five
[00:06:50.940]different extruders at this system, four different dryers. One of the very small
[00:06:58.080]batch dryers we shipped up and we'll be looking at it later today. Same
[00:07:02.220]principle as these large commercial machines but we have clients come from
[00:07:08.160]all over the world. Just Monday and I guess it was Tuesday and then they were
[00:07:13.680]still there yesterday. We had a group come
[00:07:15.660]from Spain so we may have a group from Bangkok. We may have a group from Kansas
[00:07:20.100]City so there's always an international presence in in Sabatha. So again kind of
[00:07:25.320]the changes of times we realize especially post COVID how challenging
[00:07:31.320]and difficult and sometimes costly it is to to travel to do research at our
[00:07:36.000]facility. We're not the easiest place to get to. Sabatha is not a large holiday
[00:07:41.100]destination so oftentimes clients will send us their
[00:07:45.000]raw materials and we will do the trials and we have a pretty healthy audio video
[00:07:50.580]system that we can stream online and then we can have interactions with the
[00:07:55.740]clients and they can watch on the on the control system what's happening and
[00:08:00.660]recommended changes to makes without actually having to make the two-day trip
[00:08:04.860]to get to to get to Kansas. So when we kind of survey our industry like
[00:08:12.060]everyone does or should do we ask you know
[00:08:14.340]what are you seeing as challenges in in your industry what what in the
[00:08:20.620]companion animal world and this not necessarily in any order but this is the
[00:08:26.040]list that seems to be coming back the the challenge of working with expanded
[00:08:30.360]ingredient inventory maybe a little unlike the the freeze-dry type system a
[00:08:36.900]lot of the dry extrusion systems deal with multiple of ingredients like
[00:08:43.680]25-30 different ingredients in these recipes and these recipes are sometimes
[00:08:49.780]least cost formulations so the recipes are changing all of the time even
[00:08:53.980]seasonal changes a large charge for energy sustainability clients are asking
[00:09:00.920]for their customers are asking for so we all need to take sustainability very
[00:09:06.300]seriously however that's defined for us what we
[00:09:09.720]can control is really how our equipment is designed making sure
[00:09:13.020]that it is as energy efficient as practical for today or maybe looking
[00:09:18.120]forward to the future as you know higher temperature heat pumps come online that
[00:09:23.760]we can take that energy and bring it back to our drying systems something we
[00:09:29.660]see in the companion animal world over the last 15 years this is really
[00:09:35.040]probably started is this idea of extended meat levels and we've always
[00:09:39.860]had pet food has always had meat in it and
[00:09:42.360]usually in the form of dried meat from a rendering facility meat and bone meal
[00:09:48.460]maybe blood meal that's where the protein normally comes from diluted down
[00:09:53.100]with cereal grains and maybe some soybeans added into it the ask over the
[00:09:58.740]last 15 years is we want a higher quality product clients are expecting
[00:10:04.480]they're willing to pay for a higher quality product more fresh meats so what
[00:10:09.960]was a challenge of us 15 years ago is we want to have a higher quality product
[00:10:11.700]the meat levels of that time and the meat levels today are just completely
[00:10:16.740]different and this is kind of springs-board off of where traditional
[00:10:20.400]cooking extrusion ends and then we go to the dryer as we may be looking at some
[00:10:26.380]other thermal processing system and we'll get into this in a bit of the
[00:10:30.000]thermal processing system other than an extruder feeding into a dryer with ever
[00:10:34.980]higher meat levels because higher meat levels do come with challenges for
[00:10:38.100]extruders you can only push so much meat because we
[00:10:41.400]have to get that mechanical energy into the extruder as you add more water as
[00:10:46.680]you add more oil both of these are difficult to overcome and get some
[00:10:52.500]specific mechanical energy into the product so we move more towards thermal
[00:10:56.880]type process nutrient losses are always important especially as we're dealing
[00:11:01.640]with some ever more expensive nutrients especially like in the aquatic world
[00:11:06.720]where we have lysine methionine
[00:11:11.100]sometimes there's some pigment degradation that we need to be very
[00:11:13.660]careful for so we watch the nutrient losses or pigment losses as we're going
[00:11:19.220]through the system safety hazards of course it's across the industry
[00:11:23.240]production costs all over has changed a lot especially in Europe over the last
[00:11:28.380]five years kind of moving systems from what was maybe natural gas to now natural
[00:11:34.800]gas is very expensive oh wait we don't have any natural gas at all we have to
[00:11:40.800]switch over to some other steam heat system okay natural gas is back on so
[00:11:45.540]the fluidity of energy throughout the world and I it doesn't seem like this is
[00:11:50.300]going to be changing so overarching it's just the process complexity one factory
[00:11:57.000]is being asked to do several different things I didn't even put on here
[00:12:00.000]probably the most common thing everybody has is workage so trying to find
[00:12:05.160]qualified employees in very complicated facilities and as
[00:12:10.500]some seasoned employees are leaving aging out how do we get that next
[00:12:16.260]generation trained and enjoying this career enough that they're not here for
[00:12:23.320]two or three years and moving on turnover is very very difficult and very
[00:12:27.720]challenging so again maybe if we would look at some process trends specific to
[00:12:34.860]pet food and we don't need to go over all of these we'll have handouts you can
[00:12:39.840]look at these
[00:12:40.200]closely but these are the trends that we see either on the ingredient side of
[00:12:46.760]again fresh ingredients maybe some odd ingredients and again are these flash in
[00:12:54.640]the pans are they insect protein is this even sustainable in itself is it a fad
[00:13:01.840]or is it a trend we ask ourselves this often is there a sustainability behind
[00:13:06.600]this energy that we're going to put in to make this product
[00:13:09.900]so ingredients minimally processed a huge push and that's really where freeze
[00:13:16.460]drying and HPP really enters into the market of not wanting to have highly
[00:13:23.760]processed however one defines highly processed but I anytime you go through a
[00:13:28.140]cooking extruder I would consider that fairly highly processed high energy a
[00:13:32.880]lot of mechanical degradation there's a market segment that's really asking for
[00:13:38.460]something outside of that
[00:13:39.600]so that's either mentally processed meat with an extrusion system or mentally
[00:13:45.180]processed meat through freeze drying system mentally processed meat through
[00:13:50.640]an air-dried system so I'll speak maybe more on the air-dried system this whole
[00:13:56.120]asked to move towards the unkibble for pet food
[00:13:59.600]kibble is king I can't I can't see a place in the future just the the volumes
[00:14:06.000]of cooked kibbles that are out there that they could
[00:14:09.300]really be replaced by anything other than extrusion now there is a market
[00:14:14.400]that's asking for this so we need to listen to that market but I've been
[00:14:19.440]wrong a lot in life but I I will be surprised if extrusion is ever totally
[00:14:24.660]removed but there is a growing and a large enough market for this unkibble
[00:14:30.540]ask that you know existing clients and facilities are putting in new equipment
[00:14:36.320]this equipment is expensive so this is
[00:14:39.000]you know this is usually a five-year return on investment minimum I mean
[00:14:44.740]sometimes these large drying systems in these continuous systems minimum you
[00:14:50.820]know five six million dollars so this is something that usually requires a lot of
[00:14:55.800]thought and due diligence it has to go before corporate boards it's it's
[00:15:00.300]nothing that a client is going to get in and make an unkibble with a hot air
[00:15:05.400]convection dryer and wow that market wasn't
[00:15:08.700]there like we expected it these are big decisions clients give these a lot of
[00:15:13.560]thoughts so inclusion of toppers kind of does go into this minimally processed
[00:15:19.680]again when we do make either freeze-dried or air-dried these products
[00:15:25.200]are substantially more expensive than a cooking extruded type product so the
[00:15:30.500]market may not allow $40 per pound freeze-dry or maybe
[00:15:38.400]with the air-dried type system $20 per pound that market may
[00:15:43.740]not tolerate that when the client is really willing to spend $3 per pound on
[00:15:48.840]their pet food so what could be a happy medium is to use some of this very
[00:15:54.120]expensive freeze-dried very expensive air-dried as a topper or a partial diet
[00:15:58.680]we're getting getting a lot of asks for that and again sustainability that that
[00:16:04.200]we cannot control regenerative agriculture but what we can control
[00:16:08.100]the the carbon smart how we're designing our equipment the ability to
[00:16:13.200]upcycle components there are raw materials that are available this is an
[00:16:19.200]example of some toppers of different products the top left with the green are
[00:16:25.320]like raw peas that are added into the this is a traditional cooked extrusion
[00:16:30.780]system so these peas are stable enough that they can pass through this
[00:16:34.880]aggressive extruder the other side
[00:16:37.800]we've got like freeze-dried product product is not go through an extruder at
[00:16:41.220]all is then later and added as maybe five or six percent of an extrusion diet
[00:16:47.100]so the marketing kind of enters into the picture here that hey we have low
[00:16:51.900]processed or portion of the diet is minimally processed clients are getting
[00:17:00.180]very savvy with all the information that's out there so clients again are
[00:17:07.500]actually truly reading the label they want to know what is in this pet food
[00:17:13.500]again maybe more than what is in the fun pack at McDonald's for the children that
[00:17:20.520]they're eating so there are clients that are very specific there's markets that
[00:17:25.260]are being developed for customized orderable recipes that then later could
[00:17:32.280]be delivered like by Amazon specifically a recipe that's tailored for
[00:17:37.200]your pet or what you want your pet to eat so just going to the pet food store
[00:17:43.500]or the grocery store and getting a 50 pound bag of pet food not as common as
[00:17:49.320]it used today used to be it's just the personalization of pet food is is real
[00:17:54.240]and again I don't want to spend a lot of time on here but the sustainability
[00:17:57.920]upcycling the regenerative agriculture this really started that maybe for us
[00:18:03.420]more in the European market there always seem to be at
[00:18:06.900]least five years ahead of us in the States and the large multinational
[00:18:12.360]companies Scandinavian worlds that we're looking at salmon feed what can we
[00:18:18.080]do to have the least footprint that we can so they go back to the producer of
[00:18:24.720]making sure that their fish that they're getting from Peru is either sourced the
[00:18:29.180]best that it can be or they're looking at fermenting and making their own
[00:18:33.140]protein on site in Norway so it's really
[00:18:36.600]interesting the projects that we're running into we get involved in that
[00:18:39.920]because they're needing to drive dry down these fermentation processes so
[00:18:46.420]yeah let's kind of look trying to take this right back to the dryer part and
[00:18:50.520]sustainability in our world as we're talked with factories in in the pet food
[00:18:56.460]realm the energy efficiency is a number that's measured over and over we don't
[00:19:02.400]look so much at electricity the dryers that we use
[00:19:06.300]typically are thermal that is normally indirect steam high-pressure steam
[00:19:12.600]coming into our dryers type of a radiator system not unlike a radiator in
[00:19:17.100]a car engine or more often a direct fired burner that's firing something
[00:19:24.000]natural gas liquid propane butane something like that and we're heating
[00:19:28.680]that so the litmus test for our industry has been for energy efficiency how many
[00:19:36.000]kilowatts are you using of natural gas to evaporate one kilogram of water so
[00:19:46.500]again if we just kind of go back for the years of like 1970 to where we are today
[00:19:52.380]not only you can see the number of the amount of energy has come down some
[00:19:58.380]through design some through design improvements others through reuse of energy
[00:20:05.700]reusing warm air back to the dryer again looking at now heat pumps to take
[00:20:12.480]this warm exhaust air recompress it and bring it back to the system these are
[00:20:19.000]really heavy-duty heat pumps so that's kind of the challenge we have an
[00:20:22.140]industry I think the ask is there more than the heat pump capabilities and
[00:20:28.620]again some of these heat pumps that we're working with these for high
[00:20:31.460]temperature heat pumps were kind of right back to the sustainability
[00:20:35.400]because the refrigerants that work best in our high temperature dryers are often
[00:20:40.560]becoming out of favor or out of law in the European Union so there's two things
[00:20:47.040]we look at what's your energy efficiency how many kilowatts how many kilo
[00:20:49.980]calories of gas are you using to evaporate a kg of water that's one part
[00:20:55.320]of uniformity of sustainability the other part is as you have this product
[00:21:01.280]that's coming out of the dryer how uniform is it so again this is a continuous
[00:21:05.100]product you put the product on the dryer you set the little dial I want it inside
[00:21:10.500]this dryer for 20 minutes so you have the sheet of product that's coming with
[00:21:14.760]you to you that's dried as it's leaving so it's really important of how uniform
[00:21:20.640]is product a to product B product C product D so the tighter that uniformity
[00:21:25.500]is the less energy you're going to use to dry it and the more product or the
[00:21:31.480]more moisture you can sell so it's a win-win for everybody
[00:21:34.800]spend a lot of time on making sure that dryers are designed to be uniform
[00:21:40.020]moisture leaving the system so again as we kind of look at these hot air dryers
[00:21:47.300]they're large vessels they're continuous again product is put on a
[00:21:54.540]conveyor they may be a single pass they may be a to pass this depiction happens
[00:22:01.140]to be a to pass dryer we have configurations that are
[00:22:04.500]three pass four pass bypass six pass most commercial dryers fall into the one
[00:22:10.560]two or three pass they're fairly large units and again remember we do like half
[00:22:17.040]of our stuff overseas so we have to be thinking how can we get these large
[00:22:22.800]dryers put into a container sent overseas unloaded and bolted back at the
[00:22:29.260]factory so we also do a modular type design we call these sections
[00:22:34.200]so every time we have one of these top fans on this machine this is a section
[00:22:40.160]each one of these sections is seven foot so seven foot with a little bit on
[00:22:47.400]either side of it really slides nicely into an eight foot shipping container
[00:22:51.880]that's why almost everybody kind of uses this building block of seven foot
[00:22:55.800]modular sections low to moderate airflow these style of dryers
[00:23:03.900]are hot air we push air they are convection dryers the fans on the side
[00:23:08.080]of the dryer push air through the system I would call it moderate airflow like if
[00:23:13.400]you would have a household fan in front of you probably the medium setting so by
[00:23:18.200]the numbers we calculate about 125 150 feet per minute is the air velocity
[00:23:24.020]going through the product bed these are not fluid bed dryers fluid bed dryers
[00:23:28.560]are like another classification altogether where you blast terrific
[00:23:31.500]amount of air through the product
[00:23:33.600]and you lift product around in a fluid bed dryer these dryers are designed to
[00:23:38.080]just have air percolate through remove the moisture through the air stream if
[00:23:42.420]we ever push so much air through the product bed that we lift the product off
[00:23:48.000]of the bed we're really in trouble because then it kind of turns into a
[00:23:51.240]tornado we get short-circuiting of air so we really do control closely the
[00:23:57.860]amount of air that passes through our dryer beds so uniform
[00:24:03.300]drying time no question about that we what what comes in will come out at the
[00:24:08.040]time that you ask it to come out so general handling of product not as
[00:24:13.380]gentle as a freeze dryer because these are mechanical conveyors and if we have
[00:24:18.420]a two pass dryer we have a drop from conveyor to conveyor to conveyor to
[00:24:22.480]conveyor that drop may be two foot three foot we have maybe some slides and gates
[00:24:28.480]in there but it's more gentle than other forms of drying so
[00:24:33.000]gentle product handling is is kind of subjective and fairly fairly small
[00:24:38.640]floor space I know these are huge machines but we're moving pretty high
[00:24:41.920]capacities through these things so the the amount of capacity that you're
[00:24:47.440]getting through them through the piece of equipment for factory square footage
[00:24:53.280]or square meters of a factory is really pretty high so again as we're talking
[00:24:58.420]about you know what what products do we run through these type of hot air dryer
[00:25:02.700]and we're talking about you know what what products do we run through these
[00:25:06.000]type of hot air dryer and we're talking about you know what what products do we
[00:25:09.600]run through these type of hot air dryer and we're talking about you know what what
[00:25:13.680]what products do we run through these type of hot air dryer and we're talking
[00:25:16.320]about you know what what products do we run through these type of hot air dryer
[00:25:19.320]gluten that that wheat that soybean it gluten that that wheat that soybean it
[00:25:24.960]is expanded at the extruder and then we take it from that point reduce the
[00:25:30.900]moisture from say 20% moisture down to a stable 5% moisture companion animal
[00:25:36.140]aquatic feed and we do get into a few in industrial applications but again here I
[00:25:42.600]just wanted to retouch on this the the black box you know these are large
[00:25:47.200]pieces of equipment
[00:25:49.060]everyone is generally designed for a specific application we have a few
[00:25:56.660]cookie cutter machines this is as close as we would have to a cookie cutter pet
[00:26:03.260]food dryer that is like 10 metric ton per hour it's pretty high capacity in
[00:26:08.360]our world that's kind of a low capacity and again when we measure 10 metric ton
[00:26:13.700]we usually talk product that's leaving the dryer so we're not talking 10 metric
[00:26:18.280]ton at
[00:26:18.800]23 percent moisture coming in we're talking 10 metric ton at the 7 percent
[00:26:24.380]moisture coming out this is again a pretty modest throughput machine so
[00:26:29.580]things we can change obviously the number of passes we have we can change
[00:26:33.960]the unit lengths on this machine this one shows four sections we go much
[00:26:39.680]longer than that sometimes it would go much shorter than that something else we
[00:26:43.160]can change is the actual inside conveyor where we lay the product so 4 foot 5 foot
[00:26:48.540]8 foot 10 foot on occasion will go up to 12 foot so quite a few different general
[00:26:56.960]component selection but again as you look at these different dryers that we
[00:27:02.100]have out there in quite different applications from standard pet food when
[00:27:08.400]I say standard pet food no meat whatsoever
[00:27:10.620]to like a high meat of a thermal twin type system might be 12 ton an hour or
[00:27:18.280]a corn puff free delay type think a cheeto type product whatever this is the
[00:27:25.460]the how these machines operate are really pretty similar so we have a
[00:27:28.960]heater we have fans we have conveyors it's just putting all of these pieces
[00:27:32.860]together to get to the rate that we need question yeah so again the large dryer
[00:27:47.260]on the
[00:27:48.020]right is really getting up to some of the largest machines that that we would
[00:27:51.520]manufacture and again different machines for different applications this is for a
[00:27:57.560]salmon feed style dryer and this is truly to feed fish and it's almost more
[00:28:03.860]like a feedlot mentality these fish need to be fed all the time they're a
[00:28:09.020]seasonal thing so they'll start out very juvenile and as the fish grow through
[00:28:13.040]the season they eat more and more as there's more daylight in some parts of
[00:28:17.260]the world
[00:28:17.760]fish eat all of the time so these type of very large dryers have to be able to
[00:28:23.640]turn on and operate at these really high capacities and not turn off for
[00:28:29.280]sometimes 14 18 20 days at a time so there that group's idea of sanitation
[00:28:37.520]and clean out is going to be completely different than say a Frito Lay's version
[00:28:41.920]of sanitation and clean out so a lot of different applications here is an
[00:28:47.500]example it's interesting we talked about onion rings this is a very unusual ask
[00:28:55.000]from industry for us we had a client ask us to design and develop supply a dryer
[00:29:03.220]for onion rings this isn't just to dry onions this is actually to take the
[00:29:08.200]onions that were sliced coated and then fried and then we took that material
[00:29:16.060]from about 30%
[00:29:17.240]moisture and passed it through a unique design so this is a single pass dryer
[00:29:22.900]falling over another single pass dryer because the wet product is going to be
[00:29:29.180]quite a lot different than the dry product and this dry product is going to
[00:29:33.500]go into a canister and sealed very tight I mean think think like a French's type
[00:29:39.880]onion ring so this product is coming off of the dryer at less than a half a
[00:29:44.960]percent moisture which in our world is quite
[00:29:46.980]quite low so we have to handle this the way this dryer process is really quite
[00:29:52.080]different from the beginning to the end not only the way we dry this product but
[00:29:56.880]as we're drying it we're throwing heat into it and then when we add heat into
[00:30:00.960]it we have to take some of that heat back out of it or that product will
[00:30:05.600]recondensate in the air so we have coolers usually we just pull factory air
[00:30:12.120]through the cooler to bring the product temperature down you can imagine if we
[00:30:16.720]have product that's you know almost bone-dry and we bring factory room air
[00:30:22.540]in here this is conditioned air but it's still probably 40% relative humidity in
[00:30:27.880]here if we would bring this kind of humid air through that product it's
[00:30:32.620]going to wick some moisture back up through the system so we actually had to
[00:30:36.160]put conditioning the air of the cooler going to this type of a system pretty
[00:30:41.560]unusual another example of a very small dryer we're again back to one section
[00:30:46.460]three pass relatively low capacity about 500 kg per hour of like a again
[00:30:53.480]think of kind of like a cheese puff type thing the products first extruded it
[00:30:57.560]comes to us in our world my world pretty dry 14% moisture we need to take it to
[00:31:03.280]about 1% moisture we do this really short time four or five minutes in this
[00:31:07.780]toaster oven so we're not only drying it but we're going to get some you know
[00:31:11.600]crunch to it some flavor characteristics so in this system we're running about 190
[00:31:16.200]degrees Celsius so this is not a mild drying process very high temperature
[00:31:22.200]very short time well yeah some other applications of breakfast cereal type
[00:31:33.000]not just breakfast cereal breakfast cereal is pretty easy it's when you get
[00:31:37.020]to the challenges of after the product is dried and now we need to do the
[00:31:42.820]topical coating some of these topical coatings can
[00:31:45.940]really be hard to deal with honey nut Cheerios whoever came up with that idea
[00:31:52.120]bad idea you imagine 30% honey that's laid onto a product with like almond
[00:31:58.240]slivers and then you need to dry this honey down in a dryer and then oh by the
[00:32:04.280]this is a kosher facility so we need to be clean out ready for they want to do
[00:32:09.620]things other than honey nut Cheerios so lots of products require just different
[00:32:16.100]applications so kind of back to how these hot air dryers work and again this
[00:32:22.840]this concept is really the same whether we're making Cheerios or whether we're
[00:32:29.220]making salmon feed or pet food the concept inside the dryer is really
[00:32:35.280]pretty similar again this is one of those one sections so seven foot two
[00:32:38.460]point one meter long here and you can see that there's a whole bunch of arrows
[00:32:43.460]in here arrows change colors that's the changing of the color of the arrows is
[00:32:50.660]kind of trying to show temperature differences so as we take air past the
[00:32:58.800]heating unit up top this happens to be a gas heater just a direct fired burner
[00:33:02.760]inside a dryer the air is being heated up let's say it's being heated up to a
[00:33:08.240]hundred degrees Celsius and that air is really pretty dry right now that's
[00:33:12.780]before it's being introduced to the product bed it shoots down left hand
[00:33:17.220]right hand one of those plenums and then that hot air gets shot into the product
[00:33:22.340]bed and then it will either go up or down
[00:33:25.560]through the product bed as it does that hopefully if we're doing
[00:33:28.380]our job right it's going to pick up some moisture so that product that was 20%
[00:33:32.400]moisture at the beginning of this seven foot long section hopefully when it
[00:33:37.700]leaves that it's going to be 18% so we've got 2% moisture that's in the
[00:33:42.680]airstream so that cooler more humid airstream change a color of like gray or
[00:33:49.080]brown that brown arrow comes back over and it
[00:33:52.620]loops back and is reheated so air is recycled
[00:33:57.960]in these dryers over and over depends on the product the evaporative loadings
[00:34:03.640]there's a rule of thumb you know 80% of the air stays inside the dryer and is
[00:34:09.340]ran around and around and around so if you if you don't take that moisture out
[00:34:14.820]this thing will turn into a big swimming pool control of that exhaust air is
[00:34:19.560]really critical for efficiency if you pull too much exhaust air out you're
[00:34:24.520]going to have lower efficiency if you don't pull
[00:34:27.540]enough exhaust air out you're going to have a dryer that's not operating to the
[00:34:33.700]capacity that that it could operate at
[00:34:37.940]so again this is kind of inside the dryer again continuous these are not
[00:34:45.380]when we say trays these are not stackable trays that you know static
[00:34:49.620]these are on a on a conveyor you can see a sprocket they're different versions of
[00:34:55.480]trays for
[00:34:57.120]different applications most trays use a stainless steel style tray and again
[00:35:04.640]this does not only transport the product through the dryer but remember we were
[00:35:09.720]pushing the air through the product bed so we have to have openings in these
[00:35:15.360]trays so let that hot air pass through 30 40 percent open area on these trays
[00:35:21.880]so the so these trays they air passes through either up or down
[00:35:26.700]and we stack product really quite deep maybe unlike a freeze dryer where we
[00:35:32.400]have to have almost single layer to have that good conduction we're using hot air
[00:35:38.880]as our medium so generally we want product to be as stacked as deep as
[00:35:44.220]possible on top of these trays so that might be four inches deep that might be
[00:35:49.460]six inches we have some applications that are 10 and 12 inches deep
[00:35:56.280]yeah so again there's a lot of data here but we don't need to go through all
[00:36:01.080]of this but again this is I just kind of ran a spreadsheet of clients are asking
[00:36:07.440]well you have this dryer it's a 10 ton an hour dryer why can I run 12 through
[00:36:14.920]it or why can I only run two metric tons through it the dryers are an evaporator
[00:36:19.920]you know kind of kind of like any evaporator we need to be thinking about
[00:36:23.880]the this machine
[00:36:25.860]can evaporate so much water and what I've done here and I get I know this is
[00:36:29.940]very small you can look at it later in your handouts but essentially what I've
[00:36:34.860]done is we look very closely this is the exhaust fan remember I'd mentioned like
[00:36:39.140]20% of the air is pulled away from these dryers so these are the exhaust fans are
[00:36:43.980]usually stationed quite a ways away from the dryer they're aspirating that 20% of
[00:36:49.200]the air then that is just sent right out the chimney to atmosphere as you go past
[00:36:53.340]a pet food factory you'll see a chimney
[00:36:55.440]with lots of smoke coming out of that smokes hopefully not smoke hopefully
[00:36:59.820]it's humid air so that 20% air is passing through the fan but what I
[00:37:04.260]really care about is the evaporative loading so what I've set this up I've
[00:37:08.520]looked at standard pet food again 23% moisture and we're coming out at 9% on
[00:37:15.720]each one of these looks and I've set this dryer up that the amount of water
[00:37:21.780]that we want running through that exhaust fan
[00:37:25.020]is like 2700 kgs per hour so I kept that constant so 2700 kgs of exhaust air
[00:37:32.280]going out of the factory on all of these setups so if we have a what was
[00:37:38.520]traditionally a normal pet food which would be 23% moisture in 9% moisture out
[00:37:43.860]that dryer would be rated for 15 metric ton per hour and this is really
[00:37:50.940]important is as you start adding moisture to this material
[00:37:54.600]the evaporative loading goes up well this evaporator the dryer can only take
[00:38:00.420]away so much moisture so we have to compensate for that so here we're
[00:38:04.020]looking at like what we would call the next category of meat 0 to 30% fresh
[00:38:09.100]meat which again in our world would have been a high meat loading 15 years ago
[00:38:14.840]now it's like that's a very low meat loading but let's just pretend we're at
[00:38:19.560]30% meat going through this system we're no longer at 23%
[00:38:24.180]moisture coming in we're at 28% again we're going to keep the evaporation
[00:38:28.420]through going through the exhaust the same so what was a 15 metric ton per
[00:38:33.000]hour at no meat has dropped down to 10 ton per hour at modest meat take that
[00:38:39.720]meat level up again 40 50 percent fresh meat now we're kind of getting into the
[00:38:44.920]higher loadings of a modern type system that 15 ton an hour is about cut in half
[00:38:51.500]eight point five push that meat level up again
[00:38:53.760]meat load harder yet so we're now 44 percent moisture coming in again same
[00:39:01.080]loading going through the fan what was 15 metric ton is four point five so one
[00:39:08.160]third the production throughput same evaporative loading so this is why some
[00:39:14.720]clients some facilities look at ways to okay how can we concentrate this meat
[00:39:19.800]level because everybody wants to push their equipment as hard as possible
[00:39:23.340]so if we can take that meat and pre concentrate it down have it not be 70
[00:39:28.920]percent but have it be 45 percent moisture and then you bring it to the
[00:39:33.480]system you can push more product through the production line hot air dryers these
[00:39:40.500]are can't get around that we use hot air hot is defined for us again usually at
[00:39:48.340]least 80 degrees Celsius standard hot air
[00:39:52.920]pet food dryers without anything special happening I'm in there you're running at
[00:39:57.920]about 130 280 degrees Fahrenheit 130 Celsius but the important part of what
[00:40:04.140]we're doing on any drying system in your oven anywhere is as you heat air up what
[00:40:11.980]happens air expands it can hold more water we have a lot of fancy psychometric
[00:40:17.960]charts we go through and look at this but as an example for that I essentially took
[00:40:22.500]one we we speak metric at Wenger a lot because we do so much international
[00:40:27.420]stuff so anyway one cubic meter of air and we have it relatively cool 20 C 70
[00:40:35.580]degrees Fahrenheit or so we saturate that air completely to where just about
[00:40:40.440]ready to hit the dew point it's just about ready to turn into a fog that
[00:40:44.220]relatively cool air can only hold like 14 grams of water you start warming that air
[00:40:52.080]up and that's what we're doing in our dryer we're warming that air up that air
[00:40:56.640]now can hold more water warm it up warm it up warm it up so even moving from a
[00:41:03.000]20 degrees C to a pretty modest 90 degrees C we're like 1400 grams of water
[00:41:10.320]so we like a hundred times more water holding capacity of that air and that's
[00:41:14.700]the real reason that we push hot air through our dryers so an example of
[00:41:21.660]this again kind of going back to high meat type kibble we do a lot of drying
[00:41:30.300]curves everybody kind of does drying curves you want a fingerprint on how
[00:41:33.420]your product dries this is a product that came in at came into our dryers at
[00:41:40.220]we have moisture content kind of a wet waste basis on this axis so this product
[00:41:46.260]came in at 55 percent moisture it's pretty wet and then all that we did was
[00:41:51.240]change the drying temperature 80 100 120 degrees C hold it constant through
[00:41:58.200]the whole drying time and then we look at retention time here how long it took
[00:42:04.260]to dry this kibble from 55% moisture this was a soft moist product so we
[00:42:10.260]didn't need to go completely down we had it stable water activity about 15% but
[00:42:15.360]the real takeaway here is obviously hotter temperature shorter residence
[00:42:20.820]time so 90 minutes at 120 degrees C production people say fantastic this is
[00:42:27.480]perfect we'll push it hard nutritionists say no way you're hurting our product we
[00:42:32.820]can't run that hot so then we look at lowering the temperature inside that
[00:42:37.980]dryer to a hundred degrees C so what was 90 minutes now takes 170 minutes to make
[00:42:46.800]the super premium product let's just keep taking it cooler and cooler
[00:42:50.400]bring it down to an 80 degree C and we're like 240 minutes over three hours
[00:42:57.120]so doesn't make sense so we do this oftentimes with clients to help them
[00:43:02.460]understand what kind of expected capacities they could get with different
[00:43:07.140]temperatures but it's really three things time temperature air flow we
[00:43:11.500]talked about these all the time at wanger as you as you work with us so we're
[00:43:15.300]manipulating the retention time inside the dryer we manipulate the temperature
[00:43:19.980]of the air inside the dryer and we manipulate the the speed of the air
[00:43:25.800]going through the product bed VFDs used to be variable frequency fans used to be
[00:43:31.680]like gee whiz these are so fancy and expensive anything below 50 horsepower
[00:43:36.960]in a factory should have a VFD on it for multiple of reasons but definitely in a
[00:43:41.160]dryer you can dial in that recirculation fan
[00:43:44.220]and find the best air velocity going through the bed that's best for that
[00:43:49.560]product and when you run the next product all you need to do is change
[00:43:52.980]that recirculation fan speed you can have that best bed air velocity for that
[00:43:57.720]product so again maybe we kind of take this back to what we're really wanting
[00:44:03.840]to talk about is the unkibble process minimum processing so here are a few
[00:44:11.220]examples of products that are either out on the market or that we have made
[00:44:15.960]ourselves of the unextruded kibble
[00:44:19.140]none of these have come through a traditional high temperature extrusion
[00:44:24.480]system they've either come through a forming oven or a steam tunnel may come
[00:44:34.740]through a continuous thermal cooking device like source tech makes a type of
[00:44:43.460]a continuous cooking device and then we're going in through the extrusion
[00:44:47.660]system these were large
[00:44:48.720]kibbles they started out they shrunk quite a lot because they were like 90%
[00:44:54.900]fresh meat now we're kind of starting to get up into the freeze drying area very
[00:44:59.200]high meat level this was made with a Merrell a Revo portioner so that product
[00:45:05.160]was essentially using a chicken McNugget style press to roll this product out and
[00:45:12.660]then pass it through an air dryer
[00:45:18.300]so if we talk about meat levels again when we talk about meat it's the amount
[00:45:25.620]of meat that goes into the extrusion system we kind of break these down in
[00:45:30.120]broad classifications you know category one two and three category one is like
[00:45:34.200]what was made thirty years ago category two is starting to push the extrusion
[00:45:39.540]system the traditional extrusion system category three is really pushing the
[00:45:44.640]extrusion system and what we are looking at with these
[00:45:47.880]high meat unkibble process is really kind of moving into this category four
[00:45:54.420]and what we would call category five so essentially one part meat to one part
[00:46:01.380]dry two parts meat to one part dry so kind of looking back to the old
[00:46:09.720]traditional extrusion system this would be kind of like a fifty percent fresh
[00:46:15.360]meat this is might be what that system
[00:46:17.460]looks like it's pretty exotic in that we have a couple of drying systems here so
[00:46:24.480]essentially we have raw material that's coming in raw material that's passing
[00:46:29.760]through this factory material that's being dried then and coming out of the
[00:46:34.500]system so as we would call this say this is 50% fresh meat we would have the dry
[00:46:43.120]materials coming in here the cereal the cereal portion of the diet
[00:46:47.040]we would have the ground meat coming in here we combine these somewhere in this
[00:46:53.100]extrusion system conditioning cylinder into the barrel somewhere and then we
[00:46:57.840]cook this this is important where there is monitors here that in real time we
[00:47:03.480]can measure the temperature this is an advantage of extrusion you know this
[00:47:07.780]this critical time to kill pathogens and it really depends on where product is
[00:47:15.440]made
[00:47:16.620]as to the regulations asia has less regulations than other parts of the
[00:47:22.620]world
[00:47:23.400]Australia New Zealand they have their own regulations
[00:47:27.600]Europe has their regulations we have our regulations in the US one thing that we
[00:47:32.040]are required to do is monitor the the temperature the extrude 8 temperature
[00:47:36.720]all of the time and how we would do that is have like RTDs that are mounted
[00:47:42.000]right behind the die before this product is pushed out through the die
[00:47:46.200]and it's cut this product if you're very high in meat it's very soft very fragile
[00:47:51.840]then we need to actually take it with the belt conveyor on to the first drying
[00:47:57.300]step I call this low temperature drying but we might still be looking at 150
[00:48:05.280]degrees Celsius in this first drying step very short time so this is maybe a
[00:48:11.380]hundred and fifty degrees Celsius for two or three minutes
[00:48:15.780]the intent here is to dry this product enough that it sets up that then we can
[00:48:23.300]pass that product on to a secondary dryer and we can start stacking that
[00:48:27.620]product up again bed depth is your friend the more bed depth you get the
[00:48:31.480]more yield you're going to get out of these dryers so again at this point when
[00:48:36.400]it comes out we're doing a small amount of drying really kind of surface drawing
[00:48:41.200]the product is something we tried not to do for years and years but there are
[00:48:45.360]applications where we do want to put a skin on the product a surface dry it and
[00:48:49.800]then we can generally follow a more normal drying system but you know maybe
[00:48:54.720]even a dilute phase or dense phase pneumatic system that takes the product
[00:48:58.320]to the final dryer where we get long long retention time this might be back
[00:49:02.400]to 45-50 minutes so three minutes 45 minutes something like that in these
[00:49:08.400]type of systems so the the unkibble how do we take this extrusion
[00:49:14.940]extrusion is highly processed extrusion is bad we want natural we want air dried
[00:49:21.180]so this is a version of how some factories are doing this several
[00:49:27.540]factories are doing this throughout the world essentially taking what was this
[00:49:32.940]extrusion system right here this high mechanical energy bad high temperature
[00:49:42.040]cooking extrusion system
[00:49:44.520]and replacing it with another type of cooking system and this just happens to
[00:49:51.600]be like a steam tunnel there's other ways of doing this Merrill presses but
[00:49:56.740]this is often used a lot of steam tunnels are out in industry through the
[00:50:02.800]wet pet food process so essentially this is kind of marrying a wet process of a
[00:50:09.260]steam tunnel replacing the extrusion system and then going
[00:50:14.100]on from there on to the normal process of the downstream drying so again we
[00:50:23.820]were talking about that category four and five basically that beyond one part
[00:50:31.480]meat to one part dry now we're talking like like three parts meat to one part
[00:50:38.700]dry we're still not air dried because that's usually like nine parts meat to
[00:50:42.900]one part dry
[00:50:43.680]so there's still that change of is this it's not it's not air dried it's not a
[00:50:49.560]traditional extruded kibble it's like somewhere somewhere in between and again
[00:50:55.260]this is just happens to be one of the clients that has some of these
[00:50:58.200]facilities and oftentimes these are marketed as steamed and air dried so
[00:51:03.960]you'll see this label says steam and air dried a lot of direct marketing to
[00:51:08.580]clients with this like can't hardly buy this product I think it's impossible to buy
[00:51:13.260]this product at any grocery store any pet store chain this is like
[00:51:20.580]straight through Amazon with the price point of you know nominally 18-20 dollars
[00:51:25.960]per pound so still a pretty hefty price point so again we loosely call this
[00:51:38.220]extrusion that's coming into this type of a steam tunnel it's basically taking
[00:51:42.840]this wet product a paste forming it in ropes sometimes those ropes are shaped
[00:51:49.020]if you want some shape definition and then they pass through a thermal tunnel
[00:51:54.720]basically raining in steam for five minutes retention time getting the
[00:52:00.360]product cooked pasteurized I don't know I think there's a place for HPP in this
[00:52:05.580]world because this meat if it's raw coming in and it is not completely
[00:52:10.720]cooked coming off of the steam tunnel
[00:52:12.420]we may doing we may have temperature inside the dryer but I would be very
[00:52:17.400]reluctant to say it's any critical control point inside the dryer so here's
[00:52:24.540]an example of some of these ropes that came into the steam tunnel this is an
[00:52:33.280]example I mean each one of these little kibbles was my perfect world of about 8
[00:52:37.500]millimeter by 8 millimeter surface area to volume ratio is pretty important
[00:52:42.000]the bigger the product you get the less surface area you have to internal volume
[00:52:48.840]of the product the more difficult it is going to be able to dry so 8 millimeter
[00:52:54.120]by 8 millimeters is really a nice physical size of product unfortunately
[00:52:59.040]engineers do not run marketing or it'd be a very boring world marketing would
[00:53:03.960]not put a slide like this together so anyway so this is an example of this
[00:53:08.640]type of a product that was 70% meat
[00:53:11.580]meat so that's like seven parts meat to three parts dry so this was coming off
[00:53:16.320]of the steam tunnel and it was like 48% moisture really dense in our world
[00:53:24.420]that's pretty dense most pet foods are like 350 400 kgs per per cubic meter but
[00:53:33.640]this product as it dries down so this is coming off of the steam tunnel this is
[00:53:38.760]coming off of the final drying and we'll get
[00:53:41.160]that final drying in a bit later we kind of overdried it in this we were
[00:53:44.280]like all the way down to 4% moisture but note the density loss so we went from
[00:53:48.120]that crazy high 660 grams per liter to like 400 grams per liter so what's
[00:53:54.960]really important in these diets it seems to be is the balance of the dries that
[00:53:58.920]are in there the carbohydrates and the fiber fiber is a really important part
[00:54:04.740]of this fiber that can hold the cell structure open it's kind of like rebar
[00:54:09.400]that is inside each one of these kilobytes that are in there and the
[00:54:10.740]one of these kibbles and then as those kibbles dry it keeps the cell structure
[00:54:15.120]open so they can't collapse because no one wants to buy a bag of pet food that
[00:54:20.280]is like only 1/3 full they want they want volume so we're adding some
[00:54:26.520]moisture inside these steam tunnels nominally two or three percent so again
[00:54:32.640]continuous system what's this type of system what could it look like in the
[00:54:36.420]real world so this is an example of
[00:54:40.320]a European installation of a group that had many many steam tunnels this is what
[00:54:46.560]they did they were a pet food manufacturing company they had a lot of
[00:54:52.260]soft moist they had their own rendering facilities that's how they got into the
[00:54:56.280]pet food world so we're you know like 30 years ago they had rendering then they
[00:55:00.360]wanted to take some of these rendered off-spec products and put them into
[00:55:05.320]something value-added into pet food so they had several
[00:55:09.900]cooking extruders from wenger and now they also had soft moist type product
[00:55:15.340]canned product and they kind of combined one of their existing steam
[00:55:20.020]tunnels with the rest of the downstream wenger process and came up with some of
[00:55:25.320]these air-dried systems continuous yes so again what are we looking like
[00:55:29.080]overall for capacity somebody asked about capacity again we talked about
[00:55:33.840]capacity as it's leaving the system so in the bag final product five six
[00:55:39.480]seven percent in the bag about a thousand kg per hour and that means
[00:55:43.980]about two thousand kg per hour twenty five hundred kg per hour coming into the
[00:55:48.980]system and again all of this is happening in about two hours of process
[00:55:54.300]time yep so here's just an example again this is remember as we looked at that
[00:56:00.360]extrusion system we had that conveyor belt off of the extruder that fed into
[00:56:05.340]the first wenger dryer this is the same thing about a one point five
[00:56:09.060]meter wide conveyor belt so we have these kibbles that are cut undried and
[00:56:15.720]they're dropped into the first conveyor belt and then on to the drying system so
[00:56:19.980]this is bay one I think now there's a similar line in bay two next door so a
[00:56:25.800]long length of these dryers so steam tunnel pre drying step final drying step
[00:56:32.880]and then some topical coatings afterwards before packaging
[00:56:38.640]again here's just some some examples of recipes that we have this is nothing
[00:56:43.200]proprietary about this but you can get an idea of the amount of meat and then
[00:56:48.000]we can also share the nutrition label for this so one of these would be like a
[00:56:52.260]complete diet formulated for Fifi every day the other one would be like a topper
[00:56:58.960]very high meat very expensive recipe okay last bit we're tearing through this
[00:57:08.220]so drying is really interesting isn't it so as we do scale up so clients come to
[00:57:15.420]us all the time hey I have XYZ product we need to take it from concept to
[00:57:20.700]market if it's something that we've done over and over we've got a pretty good
[00:57:27.540]database and we have actually our dryer model like this is a model of what I
[00:57:32.700]start plugging information into I can configure a dryer
[00:57:37.800]dryer for the length and width and the heating that we're having into it and
[00:57:42.960]then I draw and I pull in a product of what we're wanting to run whether this
[00:57:48.000]be a cheese puff or whether it's a 40% meat pet food and then I start
[00:57:54.900]populating this model and then it can do some pretty solid predictive analysis of
[00:58:01.860]how this dryer is going to operate the temperature inside the dryer if I start
[00:58:06.540]changing temperature
[00:58:07.380]what's that happening to product inside the dryer how's the temperature changing
[00:58:12.600]inside the dryer
[00:58:13.800]what's the capacity looking like and then we can take that back and start
[00:58:18.720]looking at how hot did the product get inside this dryer because normally we
[00:58:23.220]don't run these large dryers at one temperature we start throttling that
[00:58:27.000]temperature down as that product passes through wet product has a good amount of
[00:58:32.040]mmm like evaporative cooling built into it so as you start
[00:58:36.960]heating that product and it starts drying there's a point in there that it
[00:58:42.000]can no longer evaporate water faster than energy can come in we call that the
[00:58:48.120]critical moisture content critical moisture content is different for any
[00:58:51.900]different product but essentially that's telling us on the drying curve if we
[00:58:55.620]would have looked at an axis over here of the product temperature essentially
[00:59:00.980]that product is cooling itself off and at some point it's going to start
[00:59:05.100]absorbing energy
[00:59:06.540]from the heaters and from the airstream and that product is going to start
[00:59:10.220]warming back up so we design a lot of our dryers around where is that critical
[00:59:14.940]moisture content so essentially if we have a pretty good handle on this
[00:59:19.800]product if we've done this product like 47 times before our model is really
[00:59:25.340]pretty good and pretty solid we do a lot of contracts around this model with
[00:59:29.160]nothing else if this is a unique and unusual product yep we have to go back
[00:59:35.400]to R&D
[00:59:36.120]so at our center and we brought one of these small dryers here of essentially a
[00:59:42.480]roll-around cart that mimics what we're doing it inside of our dryers so
[00:59:48.740]essentially in this vessel we've got a small conveyor this is batch this is not
[00:59:53.760]continuous but it's just R&D so we will fill this chamber we will set this
[00:59:58.560]dryer to how we want to run temperature how we want the airflow maybe modify the
[01:00:04.360]humidity of that air
[01:00:05.700]basically mimicking what's going on inside the dryer and then if we have a
[01:00:10.500]pre-known mass and a pre-known moisture content of this product we simply just
[01:00:18.000]start weighing it in weighing it off
[01:00:20.580]wait some time weigh in weigh off it's pretty exciting but over a course of an
[01:00:26.380]hour you're going to have really pretty good sets of data to get these drying
[01:00:30.280]curves to know how product is dried so we've got like three of these little guys
[01:00:35.280]because it's very difficult to ship some wet material throughout the world so one
[01:00:41.460]of these is in Europe right now and one is in well two of them are in Europe I
[01:00:46.080]guess now and one is at UNL so these are type of roll-around carts that we can
[01:00:50.460]send to clients to do testing at their facility with with live material because
[01:00:55.620]if one does need to exercise a bit of caution if you're freezing product and
[01:00:59.540]you send it for us to test because there is some changes that happen in that
[01:01:03.960]freezing
[01:01:04.860]so again this won't show up when we do the drying examples in this cart later
[01:01:13.320]today but as we download this information as we weigh this on there's
[01:01:18.000]just a whole plethora of data that we get and from this I can take it back and
[01:01:23.220]start sizing up a piece of equipment but essentially I mean it's kind of just
[01:01:29.520]essentially a mass balance flow so as we size up this dryer
[01:01:34.440]if I know you know how many what's your production rate what do you want this to
[01:01:39.240]be two metric ton per hour five metric ton per hour and then through these
[01:01:44.280]drawing curves we can find hey what's the best time it took 30 minutes okay
[01:01:49.320]that was half an hour we know the bulk density this material
[01:01:52.320]and we know the bed depth that we can run at that pretty simply just kind of
[01:01:56.920]goes back to how much square foot of a dryer that we need how many square
[01:02:01.080]meters of a dryer that we need and then we can start
[01:02:04.020]talking about okay we know it's going to take 2,000 square meters how do we get
[01:02:10.020]this best fit to the geometry of your factory is it a five section three pass
[01:02:14.640]dryer is it a two section six pass dryer so then it kind of comes back to what is
[01:02:20.340]realistic for a factory to fit into their space and we do this with clients
[01:02:24.460]just quite often she's kind of trying to break it down to something that's
[01:02:27.960]reasonable and understandable for for everyone
[01:02:31.200]and again the challenge is we're usually not doing this
[01:02:33.600]for one product and the whole matrix of oh I want to run 18 different SKUs some
[01:02:39.220]run easier than others sometimes we need to make compromises of okay what are
[01:02:42.960]your top three products and we can design the dryer to run most efficient
[01:02:47.580]around those three products and when the dryer doesn't run so well and it is what
[01:02:52.200]it is and you may just have to run a little less efficient or run at a lower
[01:02:57.060]capacity for those products so yeah so that's kind of really what I had
[01:03:03.180]we are pushing research I enjoy being at Wanger I've been with Wanger for quite a
[01:03:13.260]while a real research driven company it is a bit in our DNA can probably count
[01:03:21.120]on one hands one hand the times that I've had kind of a gee whiz idea that
[01:03:27.480]management it says nope you're not going to do that now that's not saying we're
[01:03:30.740]going to take it to commercialization but we
[01:03:32.760]really we have a lot of freedom to think at Wenger and this is great for a
[01:03:36.480]lot of bad ideas but there's some great ideas in there too and it's like any you
[01:03:41.800]know any research you really have to do the deep theoretical to get to the to
[01:03:46.500]the what really is practical so R&D is on our on our horizon and the beauty of
[01:03:52.980]a horizon is you're never there right you're always looking for the horizon so
[01:03:58.800]that's that's where we are with research so questions comments I know I went
[01:04:02.340]over
[01:04:04.540]Thank you.

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Low Temperature Air Drying Overview

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