Below is the text version of the webinar “Biomass Feedstock Supply Challenges and Solutions with Idaho National Laboratory,” presented in January 2022 by the U.S. Department of Energy Bioenergy Technologies Office.

[Begin audio]

Erik Ringle, National Renewable Energy Laboratory

Well hello again everyone and welcome to today's webinar, Biomass Feedstock Supply Challenges and Solutions with Idaho National Laboratory. I'm Erik Ringle from the National Renewable Energy Laboratory and before we get started I'd like to cover some housekeeping items so you know how you can participate today. You will be in listen only mode during the webinar. You can select audio connection options to listen to your computer audio or you can dial in through your phone. For the best connection, we recommend calling into a phone line. You may submit questions for our panelists today using the Q&A panel. If you are currently in full screen view, click the question mark icon located on the floating toolbar at the lower right side of your screen; that will open the Q&A panel. If you are in split screen mode, that Q&A panel is already open and is located at the lower right side of your screen. To submit your question, simply select all panelists in that Q&A drop down menu, type in your question or comment, and press enter on your keyboard. You may send in those questions at any time during the presentations. We will collect these and, time permitting, address them during the Q&A session at the end. Now if you have technical difficulties or need help during today's session, I want you to direct your attention to the chat section. The chat section is different from the Q&A panel I just mentioned and appears as a comment bubble in your control panel. Your questions or comments in that chat section only come to me so please be sure to use that Q&A panel for content questions for our panelists.

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Just a few more items before we get to the presentation. This webinar is brought to you by the Bioenergy Communicators Working Group also known as BioComms. This group is sponsored by the U.S. Department of Energy Bioenergy Technologies Office also known as BETO. The BioComms Working Group includes bioenergy communicators, laboratory relationship managers, and education and workforce development professionals from the National Labs and the BETO organization who gather once a month to strategize on how to effectively communicate and promote BETO-funded research to the public. The BioComms Working Group also provides the public the opportunity to learn about current and emerging bioenergy technologies, projects, and partnerships through monthly webinars.

Which brings me to the agenda for today. We have two speakers today Dr. Lynn Wendt from Idaho National Laboratory, also known as INL. She will talk about Feedstock Logistics and Preprocessing R&D at INL and, also, Dr. Luke Williams will present on the Challenges and Solutions for Working with Wastes at the Biomass Feedstock National User Facility. And before we get started, I'd like to provide bios for both of these presenters today.

Dr. Wendt serves as a laboratory relationship manager at INL for BETO. Dr. Wendt is also a senior research scientist in the Energy and Environment Science and Technology directorate at INL. She has served as a principal investigator for multiple projects sponsored by BETO and has contributed to strategic planning for INL's BFNUF and associated programs. Dr. Wendt is a bioenergy research expert in post-harvest physiology and chemistry of biomass storage systems in microbial systems for bioenergy feedstock supply chain processes. She has pioneered the development of biomass and allergy material storage and handling systems that stabilize stored biomass materials while increasing biomass value during short- and long-term storage. Her 25 biomass related publications and three patent applications are the authoritative reference on value-add biomass storage systems. Dr. Wendt holds a B.S. in Biochemistry from the University of Minnesota and M.S. in Biology from Idaho State University and a Ph.D. in Environmental Science from the University of Idaho.

Dr. Williams joined INL in September 2014 studying the fundamental physical and chemical properties of lignocellulosic biomass as they impact thermochemical and biochemical conversions. Much of his work has, also, focused on the scale up of material handling processes to manufacture feedstocks at the pilot scale while, also, understanding real-world variability through robust feedstock characterization. Dr. Williams' later work has focused on understanding how pre-preprocessing impacts the flow ability and the non-Newtonian viscosity of high solids content biomass flurries destined for hydrothermal processing. Dr. Williams spent a year stationed with DOE BETO as a management operations outplant before coming back to INL and leading a 15 million upgrade. Prior to joining INL, Dr. Williams received his Ph.D. in Chemical Engineering from the University of Massachusetts Amherst, where his research focused on catalytic reaction engineering for the production of renewable aromatic chemicals from biomass derived sugars.

Okay before I hand it over to Dr. Wendt, I'd like to remind you that you can ask questions at any time during the presentation using the Q&A panel and selecting all panelists. We will collect these and try to address them during the Q&A session at the end of the presentations, time permitting.

All right. With that, Dr. Wendt feel free to take it away.

Dr. Lynn Wendt, Idaho National Laboratory

Thank you and is my audio okay?

Erik Ringle

Yes. You sound great.

Dr. Lynn Wendt

Great! Okay. Well thank you for the introduction. Again, my name is Lynn Wendt and I lead our Bioenergy program here at Idaho National Laboratory and I'm really looking forward to today's discussion on Feedstock Logistics and Preprocessing Research at INL. Next slide.

And so INL has the great distinction and pleasure of having one of the congressionally described national user facilities and this is the Biomass Feedstock National User Facility and the whole goal of this user facility is to help get the preprocessing, logistics modeling, and such operations in the supply chain - have those be a national facility that multiple users including government, academia, and industry can use. And so I'll go over some of those high-level areas today. We, also, we start with feedstock supply and logistics.

So our team understands resource mobilization, all of the unit operations associated with harvest collection, transportation, preprocessing, and all of the associated cost and energy analysis that goes into that. Biomass and MSW—municipal solid waste—characterization and variability management; on the bottom here you can see some of our analytical capabilities at the Idaho National Laboratory. And that really helps us understand the quality of feedstocks that are coming into the supply chain and out of preprocessing. We, also, have a core capability in Mechanical Preprocessing R&D; even all the way up to artificial intelligence-based material preprocessing operations that are controllable and tunable in real time. And, finally, the Scale-up of Conversion-ready Feedstocks. We have a process development unit that's shown on the bottom here or on the right here that we have capabilities to help industry scale and we can work with industry within our user facility or even in your areas to help solve problems that are being faced in the supply chain. And next slide.

What are some of those challenges that biorefineries are up against? On the top here you can see the supply chain operations. This is a biochemical approach to converting cellulosic material. As you can see, there's the farm here on the one side and sustainable aviation fuel on the other. And within the supply and logistics preprocessing and conversion, some of the challenges that they've seen are feeding, flowability, handling challenges; there are challenges with variability of feedstock quality—which I'll discuss next—and then, also, equipment uptime and downtime that those challenges create—stoppages, blockages, and not producing fuel at name plate capacity is something that has economic impacts for sure for industry. This is what the supply chain is up against and so our goal is, as you can see on the right here, to really understand how to supply the right type of biomass the cost, quality, and quantity necessary to support the biorefineries and in this umbrella of sustainability. Next slide, please.

These are a few pictures of supply chain challenges that have been observed previously that we are working for looking for solutions to. On the left here, you can see challenges in storage. Material is either deformed or bales have degraded or even self-heated and you're losing moisture, you're losing dry matter and the performance of those materials can be impacted. In the center here, you have challenges that are associated with flowability, clogging, and even materials not being size reduced effectively. And on the right, you can see this is a screw feeder where it has worn because of abrasion and the abrasiveness of some cellulosic material. And next slide.

So what are we doing about this challenge? INL has really refocused our thought leadership on what feedstock supply systems look like. We know very well how to make a uniform format fee stock supply system work for the industry. And in that supply chain system, that is... it is a very simple supply system that has just a couple of unit operations in preprocessing it homogenizes material, drives it, and densifies it so it can be transportable. What that system does not do is address quality. And so this quality-by-design feedstock supply systems, it actually adds preprocessing operations in the supply chain and complexity. However, it enables a few things: access to new feed stocks, selective pairing of feedstock fractions to conversion processes, and key to this all is fractionation, merchandising, and value-add. And so on this bottom figure, you can see our resources are opened up. We have plastics, municipal waste, gaseous resources, and even wet resources that we can now take in. We have multiple markets. Not just fuels, but also, chemicals, metals can be fertilizers, and even animal feed. And so this larger vision of controlling quality is our vision for how the industry is going to succeed. Next slide.

So what does this process of innovation look like and what is our model? Our model, right now, and this is what's shown here on the side, is the grain mill. And previously, as you can see on the left, grain milling was a one-unit operation. And you got one product, in this case stone mill flour, that made very dense bread. In 70 years, the grain milling added innovation and additional preprocessing in this fractional milling approach. And so, what that gives you is multiple products that have multiple quality specifications that are very specific and now multiple uses. So high fiber products; donuts, bread, any of these other things, but they're very controlled. And that innovation process, while it took 70 years, it is our model at the Biomass Feedstock National User Facility and our opportunity is to use advanced preprocessing modeling and really accelerating this process of innovation so that it can occur in a number of years as opposed to decades. Next slide.

What does quality look like for biomass resources and waste? On the top here, you can see forest residues and inherently those raw biomass sources have very different quality. Your needles are higher in ash as are your bark, you probably have some soil contamination in that sample, and then a very clean white wood fraction in the center. But those are some of the quality issues associated with forest residues. In the picture here, you can see degraded corn stover bales, herbaceous bales. Their quality has suffered, because of improper storage and that can be managed in the supply chain. And then as we work into municipal solid waste, you can see the inherent variability of that material just by color in this case. So you have your plastics, your papers, your cardboard, and all of those create new challenges in preprocessing. That diversity and variability requires this preprocessing so that we can achieve the feed stock specifications for conversion facilities. Next slide.

What does quality look like coming out of the field compared to what a biorefinery will accept and has a requirement for? In the field, you can have, in this case on the right, corn stover that's harvested in the field comes in at only meeting 30 percent of the quality requirements of the biorefinery. You can see these plots here or this plot here shows the range of each of these important metrics for conversion. And on the left here, you can see what the required variability is at the biorefinery. And so our challenge is how we meet that tight specification over an entire year and a lifetime of a biorefinery. Next slide.

So key preprocessing operations that help us achieve these quality specs are shown here in the top. And this picture is a representation of a theoretical biorefinery. You can see on the left the different types of waste they can accept from municipal waste algae, forest residues, herbaceous agricultural residues. And in the center here, you have all of those resources going to many co-located or distributed biorefinery midstream facilities or depots. And so this is where all this preprocessing is done. And the operations discussed there are post-harvest physiology and chemistry which is my background material introduction, milling, conditioning using water temperature pressure to change the tissue state of material, separation, fractionation; size is shown here as a key parameter. And then when you achieve the narrow quality distribution, that is accomplished by blending and then formulating into dense transportable products. You can see the transportation aspect here in the graph with the trains and the barges. And then key to this is, as I said before, these value-add fractions that we can get across the supply chain; fiber, fertilizer, animal feeder shown here as examples. And then this biorefinery at the end is the target. That can be a thermochemical, biochemical, but this type of a system is really our holistic view of what the future biorefinery looks like. And next slide.

So the capabilities that we have at Idaho. We basically are looking at how to site biorefineries based on available resources and the cost and quality and quantity of those nationwide. Our team has built models that can predict sighting of depots and biorefineries based on that resource availability and along with other things such as you know water availability or any other geographical constraints we have. And those supply chain costs consider all of the unit operations getting the material from the field or the landfill or the urban center all the way to the reactor throat. That includes harvest collection, storage, transportation, and preprocessing. And one key thing to consider is that these facilities that we are designing with these modeling exercises, they have to use a range of both inexpensive and expensive feedstocks to get their cost and quality and supply chain considerations to have that triple bottom line basically. Here, in this picture here, is an example of—based on different scenarios—the citing of different biorefineries and depots. Next slide, please.

I touched on post-harvest physiology and one key thing to think about here is that moisture can be a failure point for the industry and has to be managed. And this is true for herbaceous biomass as is shown here and especially true as we move into municipal waste and wet material where rotting and decay are naturally occurring. In the top picture here, you can see a stack of corn stover bales that have suffered wetting and associated degradation. This bottom bale here has been self-heated in storage and is brown because of that those reactions that occur. And all of these reactions can have both biological effects, chemical effects, and physical effects. And so we are really developing technologies to reduce upstream variability and degradation in harvested biomass that help downstream operations. And our team led by Bill Smith on this has determined that every percent of dry matter loss that you have upstream, especially in this corn stover situation, has an impact of 40 cents a ton of delivered feedstock cost. And so managing this quality is really critical upstream. Next slide.

We have shown that moisture management is possible in veiled systems. In this case, we have looked at taking any heat that's occurring in wet biomass and making sure that... or understanding how it can become a value add for us by helping facilitate drying. And so, through modeling efforts informing field design we've shown that we can reduce loss in the field from 12 percent to 4 percent by simply removing the moisture facilitated by self-heating. Next slide, please.

Another area of keen interest for our group is anaerobic storage and wet systems and the opportunity to use that unit operation as a value add to reduce the recalcitrance and encourage these slow physical and chemical transformations in the supply chain. And we've applied this to many different types of biomass including forest residues—you can see on the bottom here in the middle a drive over silage pile that we had put up in Kansas many years ago—and even preserved micro algae our team led by Dr. Brad Wallen on this. And so these types of storage designs can really help preserve material in this high moisture biomass and it can be very applicable to food and municipal waste. So that's something we are very interested in working with others on as well as the waste that we use expands. Next slide.

I wanted to just give a few examples of variability that's inherent to biomass types. In this case we have anatomical fractions of corn stover shown. You can see the leaves versus the cobs versus the stalks and the associated scanning electron microscopy images at the bottom here show the inherent complexity and diversity of those tissues. They all behave differently in preprocessing. So for example, leaves if you impact them with a hammer mill they can be pulverized and lost in the system, but if in that same system husks and stocks can also respond differently and they can be size reduced better by sheer mechanisms in many cases than by impact. And so we're really looking at how to address these things in the supply chain here at INL and Luke is going to show some more examples of that too. Next slide.

I mentioned woody residues before, an anatomical fractionation is critical in woody residues to achieve the necessary conversion specifications. In the picture on the right, you can see that just the anatomical fractions of a log; you have your bark, your cambium layers, your white wood—those all have very different quality specifications as shown here in the center graph. The inorganics or the ash materials within those are inherently different. Higher in the needles in the bark and that can cause downstream issues and conversions such as flagging and fouling of catalysts. And the other complexity is the age matters, so based on the age and size of the tree you have different proportions of all of these fractions. So understanding how to control that in the supply chain is one thing we have quite a bit of core research in. Next slide.

A couple examples of how we manage this quality in preprocessing. This is an example of air classification. You can see forest residue in this case at the top. It can be fractionated into all of the anatomical fractions I just mentioned and this helps to reduce spines generation and energy consumption in downstream milling. When the way that this air classification works is by basically having the biomass go through an air column and separating based on light and heavy particles and doing that at a number of different air speeds can facilitate the fractionation I've shown here. And next slide.

One other thing we pride ourselves here at Idaho is process control in preprocessing. And so this is an example of a project led by Dr. Mohammad Roni where he is looking at controlling the drying process based on the input material. And so he's using artificial intelligence-based process control software that can estimate particle size and moisture and provide that real-time control to the dryer and really give the operator of the dryer—flexibility so that we can reduce the energy consumption. Drying is one operation that does typically require quite a bit of energy input often in the form of natural gas. So understanding how we can reduce that that energy consumption is really a key thing for the industry. And next slide.

So here's a picture of our process development unit and we have all types of things from five tons-per-hour hammer milling to one ton-per-hour rotary shear milling, separations at multiple scales and loop will show you that too. But this fractional milling loop can help us get our narrow particle size distribution and our narrow quality distribution I've been describing. Next slide.

High-moisture pelleting is another example of how we can reduce the energy consumption in the supply chain. This work is led by Dr. Jaya Tumuluru. He looks at how we can combine that fractional milling for any residue or any material including municipal solid waste and pellet at a higher moisture content so that you don't have to put so much drying energy in up front before pelleting. This allows us to get a pellet that can not only be transported but has better and improved flowability performance. And next slide.

Lastly, I want to leave you with a one-sided guide to the Feedstock Conversion Interface Consortium. This is a consortium of nine national laboratories that looks at first principles-based science to help de-risk biorefinery scale-up and deployment. And they're really looking at controlling the impact of feedstock variability on Preprocessing and on conversion. And so I welcome you to go to FCIC's website and learn more about how you can collaborate with FCIC and opportunities that their research advancements that they're working on within that consortium. And with that, next slide.

This is a final summary and I've really gone through this already, but the key message here is management in the feedback supply chain is very critical to biorefinery performance. Next slide.

And I want to thank the BETO office for funding. My contact information is here and I'd like to move to the next slide and introduce Dr. Luke Williams.

Dr. Luke Williams, Idaho National Laboratory

Thank you Lynn. So today I'd like to talk about challenges and solutions for working with wastes at the Biomass Feedstock National User Facility which I will refer to from here on out as the BFNUF. Next slide, please.

So as Lynn has mentioned the BFNUF actually does a lot of work at various scales. We have done stuff all the way from field scales, collection harvest, modeling, all the way down to understanding how ash moves around in different tissue fractions as materials biologically degrade. And the way we've done this—the way we approach this for turning wastes into quality feedstocks is by following a quality-by-design process—which is really just a fancy way of saying we look at what we want to come out of the end. We go to the step before that and we say okay what material, physical attributes, chemical attributes, what processing parameters, what equipment need to be in place to upgrade the quality of this material in each step as we go along the supply chain to make a high-quality feedstock for conversion? Next slide, please.

So as we do this, we've got a lot of historical experience with biomass. Lynn has talked about how we can separate leaves and husks and cobs and stocks for materials like corn stover which is one of the primary feedstocks for the first generation cellulosic ethanol facilities. But as we upgrade this facility and move to the future we are really looking to move beyond just biomass fractionation and quality improvement to really start to work with municipal solid wastes—your bales of secondary MRF residues that might be like mixed paper and unrecyclable plastics or as we continue on moving towards composites that are often mixed layers of plastics other copolymers and metals that are becoming an ever larger part of the MSW stream that are at this point non-recyclable. Next slide, please.

So the way we've organized the BFNUF to try and break down these challenges of turning wastes into feedstocks is into five what we're calling centers. We've got materials conditioning—which is as Lynn showed a lot of our storage work where we will modify moisture, change temperature a bit to try and start to break down these materials before the mechanical deconstruction steps where we have a wide variety of mills at a wide variety of scales that are 10 kilograms or tens of kilograms. And our scale we've got attrition mills, shear mills, mills that operate with compression impact essentially all the different deconstruction tools. And we can look at how these different deconstruction mechanisms impact the particle size, distribution, roughness downstream so that we can make sure we're sending materials that flow well because flow ability is a big challenge in this industry. And in the feedstock preprocessing center, everything at sort of pilot scale, between one and five tons an hour. And across all of these different processes and scales we do characterization. Our feedstock characterization capabilities are often centered around particle size, particle size distributions, some reactivity screening, and our interfacial property centers—where we really start to utilize some of the fundamental science tools we have here at the lab like scanning electron microscopy or microcomputed tomography to look at the microstructure of these materials and understand on a fundamental level the components—be it physical forces or physical changes that are impacting the quality of this material. So I'm going to step through each of these centers now to describe kind of what we're doing in each one broadly in a decreasing size scale. Next slide, please.

So for our feedstock Preprocessing capabilities we've got unique material introduction bale processors—we like to take industrially relevant materials bales of stover, piles of forest residues, bales of MSW—and we can put them through a variety of separation and size reduction steps to improve their quality. As Lynn showed with the air classification we can separate your bark from your needles, from your white wood. Traditionally, a lot of the thermochem conversion processes have been using white wood. So a lot of our research has been around what level of sort of contamination, if you will, with needles and bark can we leave in there? Are there things that we can do with the needle and bark that help remove the ash and clean it up? What type of milling should we use to break these particles down in such a way that they don't jam in reactors downstream? We've found that particularly when working with herbaceous materials and impact milling or impact hammer mills you can end up with some pretty stringy materials where some shear-based systems like the Forest Concepts rotary shear can get you pretty uniform particle sizes. And whether you separate, and size reduce or size reduce and separate really kind of depends on the waste you're dealing with, the quality you're shooting for, and oftentimes the processes alliterate between those two over a few steps to make a high-quality product. Next slide, please.

One new tool that we've got on hand here is a gravity separator and if you could play the video I'd appreciate it.

[Plays video]

And what this tool actually allows us to do, it's different than a standard screen. It's got this sort of vibrating, rotating, inclined plane that counter-intuitively enough where it moves the light fraction down to the bottom and the heavier fraction ends up moving up and coming out the top. And this tool has actually allowed us to take corn stover and if you grind the...oftentimes the cobs will end up being a little more difficult to convert because they've got a few very different anatomical fractions in them. So if you can size reduce through something like the rotary shear that makes uniform particle size, this type of...sort of just simple gravity driven mechanical based separations can actually separate the pith from the rind, from the shaft, and you can take the high-density harder-to-convert pith and separate it from the lower density easier to convert shaft. So if you can get better fractionation that allows you to work accurate blending strategies to improve feedstock quality and streams that are harder to utilize like— let's just say the pith for instance—can be redirected to other valuable co-products streams in different industries. So, really, the goal with the BFNUF is to take these waste streams and fractionate in such a way that we give everybody the high-quality feedstock that they need. Next slide.

And first video.

[Plays video]

And one way we approach that is through different milling mechanisms. What you're seeing here is a Forest Concepts crumbler it puts out particle sizes that are much more uniform than a standard impact mill, because of the way it works and it also has attached to it an oscillating screen that allows you to recycle materials this fractional milling systems like this are highly effective at helping narrow particle size distributions and control quality. Next video, please.

[Plays video]

And we've got this at the one ton-per-hour scale which was shown there with the Forest Concept crumbler and the five tons-per-hour scale which you see here. So if you are going to do something like hammer mill forest residues and you were to just pass through one screen on your hammer mill, you'd end up with a pretty wide particle size distribution which is shown here in blue on that graph at the bottom. But if you switch your milling mechanism to something like crumbling and/or you add some screening tools like these oscillating screens you can really narrow your particle size distribution down to something that feeds well. And this is useful for both biomass and MSW. We've got a project running now where we are hammer milling old circuit boards and then running them through actually the oscillating screen system you saw on the orange tool the Forest Concepts crumbler to essentially break these down and separate them for metal recycling. Next slide, please.

So sort of one step down from our tons-per-hour systems we've got the tens-of-kilograms-per-hour systems where we either have and/or are bringing in as part of this 15 million dollar upgrade that the facility is undergoing a wide variety of mill types that we've got roller mills, various other, disk mills, attrition mills; we've got a variety of mill types coming in to essentially allow us to size reduce particles using any type of deconstruction mechanism that's really available. And once you deconstruct things we can do a lot of feed handling studies. We've got screw extruders, different types of densifiers, we've got some sort of plug screw feeders that allow us to study feed at higher compressions with various plug pipe scenarios at the end coming in. So we can really begin to get a better understanding of the feed handling and how deconstruction affects that. Next slide, please.

And we actually take a lot of this deconstruction knowledge and some basic physics using tools—that I'll discuss a little later in this presentation as well—and incorporate it into physics-based models that help us understand and predict what will happen in various processing scenarios. I mean the ultimate goal, although we are a ways off from it yet, is to develop a virtual process demonstration unit where we can play around a fair bit by linking different physical models together to get an idea of what might happen before we move into the lab and start linking different physical systems together. Next slide, please.

So before we get to a lot of this deconstruction, we often have some type of conditioning. We've got various storage reactors from the bench scale all the way up to a size where we could store a bale at a certain set of conditions and this biological degradation is something that you really have to be careful of in the real world. You may harvest your corn stover at a certain set of chemical and physical characteristics, but if you're harvesting your waste, so to speak, once a year and are trying to use it all year long it degrades and that causes significant challenges downstream for both handling and conversion as Lynn showed you many good slides of bale degradation earlier. At the BFNUF we try and we take those processes, study them under a variety of storage conditions, and look at how that can impact things like convertibility downstream. We've got a lot of tools for moisture modification, high temperature and low temperature dryers, we've got some unique solvent drying that's coming online that really helps preserve the pore structure of your materials which can impact downstream conversion, and we've got what we call tempering—be that some type of interaction with an autoclave type scenario or a tora-fire, we've got ways to use thermo mechanical deconstruction to make much more uniform materials from various waste streams that are coming in. Next slide.

And through all this we've also got some washing tools which are often viewed as a cost center, but it is good to understand how they impact conversion and we also do a lot of techno-economic analysis to make sure that if we are adding a preprocessing step anywhere along the lines that the benefit you get out of it downstream is worth the cost. So some of our researchers here—Rebecca Brown and Vicki Thompson—have worked on decontaminating secondary material recovery facility residues that are mixed paper plastic streams and seeing how they can convert in pyrolysis studies. So they took the raw MSW, they washed some of it with like a water detergent wash, and some of it with a chemical wash with this dimethyl ether which is what we've used as a solvent drying option. It's a very useful chemical that is gas at room temperature but turns into a liquid about 50 PSI. So your temperature and pressure swings for getting this to be a washing fluid or really you know 30c kind of pressure or 30c temperature swings and 50 to 100 PSI pressure swings. So it's very useful from an energetic standpoint. Next slide, please.

And after this washing, they realized that the cleaning steps can be very impactful on your oil yields for pyrolysis that we screened here at the lab. They actually increased their oil yield by about 30 percent after washing and decreased the gas yields quite a bit. Upon further investigation, it appears that a lot of this increase in liquid and decrease in gas yields were largely due to removal of contaminant potassium that essentially catalyzed a lot of breakdown during the pyrolysis process. As I remember, their techno-economic analysis was actually leaning towards the dimethyl ether as being a little more profitable than the detergent wash, simply because it was lower energy. Next slide, please.

As we turn these wastes into feedstocks, we characterize them as we go along. You've seen examples already of narrowing particle size distributions. I just showed you example of sort of the reactivity screening that we use to look at our look at the impacts that our preprocessing has on the material quality, in the MSW example. And what I'm going to show here is some work that we're doing on our chemical signature separation. Next slide, please. And you can start the video.

[Plays video]

We are partnering with a lot of different people. We've got some tools - this one from AMP Robotics - that works on sorting. And what we're doing here to sort of advance this artificial intelligence sorting research is adding new spectroscopic capabilities like mid-infrared cameras to these types of sorting systems that allow us to better identify some contaminants in these waste streams. So if you've got a picking system here like the one shown that'll remove 80 units a minute, you can really use these various sensor arrays that we're working on building here and integrating into the AI systems to find the most contaminated objects and remove them from the stream so that you can improve quality while also losing less material. This would be one of the goals of these types of projects. Next slide, please.

And, finally, we come to our interfacial properties center, if you will. And this is where we'll use SEM microcomputed tomography to really look at what's going on in these materials at a fundamental level and we can often take data from these types of studies and incorporate them into the physics-based models that we're using to try and build a digital twin of our facility. Next slide, please.

Our micro CT unit—that we're actually in the process of upgrading the sensitivity and buying some new tools and inserts for right now—really helps us understand the microstructure of the biomass and look at how that microstructure impacts deconstruction as we might have in any of our variety of milling types. Next slide, please.

We have measured the microstructure of a lot of biomass samples and then given this microstructure data over to our physical modelers—Yidong Xia in particular—to have him essentially be able to incorporate this data into the physics-based biomass deconstruction models that he builds. We're also getting essentially a compression tool that will go inside the CT system so that we can actually take a scan of a material, apply a compressive strain, take a scan again, and actually see—sort of in real time, if you will—how these materials break down. Next slide.

And this will really help improve the models. Thus far, we've had some very, very coarse measurements on forces required to break things and looked at how things deconstruct for in various grinding scenarios and we've incorporated this data into quite a few physical models that help us, again, understand what will happen if we use processes like knife milling or hammer milling. Next slide.

And what we'd like to do is take all of these different tools and apply them to a sort of new and growing problem area being the deconstruction of multi-layered packaging. If you've got metal or materials where you've got lines of plastic like copolymers and metals altogether. Right now we don't have good tools for converting such heterogeneous streams, but we believe that with the proper fractionation we should be able to get these polymers separated from the metals and allow individual recycling of cleaner streams. Next slide.

So, broadly speaking, the BFNUF is set up to take a wide variety of wastes and turn them into a wide variety of products. We try and do that primarily by solving flow ability challenges and quality challenges associated with turning wastes into feedstocks and we really aim to help facilitate the transfer of new processes and process knowledge from sort of the bench scale up to the industrial scale or at least the pilot scale in our facilities there. And with that, I would be happy to take any questions. I'd like to thank the U.S. Department of Energy for their funding and you all for your attention.

Erik Ringle

Well thanks Luke and Lynn for those interesting presentations. Some exciting research happening on feedstocks there at Idaho National Laboratory. For the audience, I'd like to point you, now, to the chat section where I just post a couple of links to great resources on this topic, but because for the interest of time I want to dive right into questions which we're getting quite a few coming in at this point. So to kick us off, you talked a little bit about municipal solid waste as a feed stock throughout the presentation and it seems like all that solid waste in landfills represents a wealth of feedstocks. So, is there a difference in biorefinery conversion specifications between municipal solid waste and the traditional forest residue in corn stover biomass? And a follow-up question to that, what are some of the municipal solid waste that biorefineries can take today for conversion into biofuels and bioproducts?

Dr. Luke Williams

Yeah, so I guess I'll take that question. If a biorefinery sets a spec...I mean that is the spec they want kind of regardless of what waste stream is coming in be it MSW or like forest residues. So, what we would try and do here in the BFNUF is take that low-cost waste and have it meet the spec that the biorefinery needs. For MSW that might be like pulling out some of the organics that are high moisture or lower carbon or too high in oxygen content, not enough hydrogen. Those types of things to maybe meet some of the specs that a pyrolysis facility might have.

I guess maybe to the second half of that question: There are conversion facilities out there now typically is oriented around gasification that are capable of taking um like secondary MRF residues that are mixed paper plastic streams. Particularly as long as they don't have too much chlorine in them that have been size reduced and densified and we would also help like find ways to remove the chlorinated materials to take some of that MSW and turn it into a feedstock or something like the gasification conversion process.

Erik Ringle

Okay thanks for tackling that one Luke.

Lynn, I think this one is more directed towards you. I wonder if you could tell us a little bit more about the Feedstock Conversion Interface Consortium or FCIC. Does the FCIC work with individual industry partners? And if so, what do companies have to have to gain by working with the FCIC and what kind of problems can the consortium help address?

Dr. Lynn Wendt

Yeah, that's a great question. So FCIC does have a number of tasks within it that focus on some of the key problems that we see. One task is on abrasion, one is on variability, they have a task focused on flowability and materials handling, preprocessing, and then both low temp and high temp biochemical and thermal chemical conversion routes. And so, that consortium is really focused on developing tools that industry can use or they can apply to them. So, some of the modeling work that Luke has shown here, that is something where we have these fundamental first principle models that have been built and can be applied to new copper designs or feeding bins. And that would be one example. Another example is they're really looking to do a lot of develop screening assays that can be used to assess a large number of samples and their potential performance, but with a rapid turnaround. And those tools could be used for different feedstocks for industry as well as applied to specific industry configurations and reactor designs, even preprocessing designs. And so, opportunities certainly exist. I recommend the group... anybody interested goes to that website and can contact the team through there or through me.

Erik Ringle

Oh great! Thanks Lynn. A lot of questions coming in and unfortunately we're not going to have time to address all of them, but I think we have time for maybe one more. And so, this one's more specific. What modeling environment or software tool set is used for multi-physics models? Maybe that one is directed at you, Luke.

Dr. Luke Williams

So yeah. Our modelers use quite a few different options. And actually they try and keep them all open source and publish them out after the fact as well. I know for some wet materials, they're looking at dissipative particle dynamics models. They do a lot of discrete element modeling. We've also got people that do the field scale models using discrete event simulation which is a little more of a Monte Carlo type system. Yeah, really the type of model I use kind of spans the gamut and is really dependent upon the size of the system and the number of things you're trying to simulate. Lynn, do you have anything to add to that?

Dr. Lynn Wendt

No, but we'd be happy to get you in touch with the researchers that are doing the modeling for additional collaboration.

Dr. Luke Williams

Yeah, for sure.

Erik Ringle

Okay great! And yeah, to that point, Dr. Wendt and Williams, your emails are here on the slide so feel free if you have questions if your question didn't get answered to reach out to them directly.

But just a big thanks to Dr. Wendt and Williams for taking the time out of your busy schedules to educate us today on feedstocks supply challenges and solutions. For more bioenergy webinars like this and other BETO-funded research, again, we encourage you to sign up for the BETO newsletter page at the bottom of the slide. The webinar recording and slides will be posted on the BETO Webinars page in a couple of weeks. And again if your question did not get answered today, please reach out to Dr. Wendt or Dr. Williams with these emails on this screen.

With that thanks everyone and have a great rest of your day.

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