Ultrasonic technology takes on hydrogen, natural gas blends

Duane Harris: Thank you, Keith. I really appreciate the invitation. And I joined Sick in March of 2020, and have had an opportunity to spend four decades in our industry. I have been looking forward to our chat today.

Larson: Awesome, awesome. Well, maybe just to start to lay some groundwork to start, maybe you just take a few minutes to really update our listeners on some of the recent activities, especially I know, in Europe they're very active to begin blending hydrogen with natural gas to help deliver comperable energy flows with lower carbon emission.

Harris: Sure. So you know, in so many areas the United States leads the world in technology and research. However, I must, we must admit regarding the blending of hydrogen with natural gas, to really help deliver comperable energy flows with that lower carbon emissions, Europe is generally, I would say, five to 10 years ahead of the United States in our research efforts today. Now fortunately, there's really great collaboration between the United States and Europe to better understand really, how can we utilize the testing that they have conducted in Europe, and the testing that we have been doing here in the US to really kind of effectively blend hydrogen with natural gas to lower carbon emissions here in the US, and really looking at that from a world type perspective?

Larson: Yeah, that makes a lot of sense. I mean, while hydrogen and natural gas are both combustible source of energy, there's some important differences, too, between the molecules that go into each. Can you kind of walk us through some of the differences and how that affects the dynamics within the pipelines?

Harris: Absolutely. And that really is a great kind of clarifying question, Keith. And that is, first off, if you look at hydrogen, hydrogen is eight times lighter than natural gas. I mean, to think of just hydrogen itself being eight times lighter than natural gas, and then if you start looking at the speed of sound, and some of you may be kind of scratching your head, well, why is speed of sound important? Well, if you use ultrasonic meters to measure gas, the speed of sound of that natural gas is really critical. And what you see is that hydrogen has a three times higher speed of sound than what you see in natural gas. And so, to take and quantify that, the speed of sound that we are used to seeing here in the United States is around 1,394 feet per second, for the speed of sound that goes through the natural gas blends that we see in the US today. Well, if you are going to move hydrogen, the speed of sound of hydrogen operates at 4,300 feet per second. And so I mean, that is just significant differences that your average person and looking at that kind of diagnostic would say something is off. And so, all that really has to be brought in to our research and quantification, and in another area that I think a lot of people might even have a misconception and that would relate to the heating value. The heating value of natural gas that you see moving in homes today throughout the United States, really operates right around 950 to 1050 BTUs per cubic foot, where the the BTUs of hydrogen is really three times lower. It runs at 325 BTUs per cubic foot. That is significantly different whenever somebody is starting to look at the BTUs value that you would see in your home, if you've now started to blend hydrogen with your natural gas.

Larson: And it's really the the sum of those differences in physical properties that allows you to determine the composition using an ultrasonic meters, because you can gauge the how much the speed of sound has changed, is that accurate to say?

Harris: Absolutely, absolutely. And that is, I would even say that's one of the key areas that Sick has been able to utilize some of these differences is really, whenever we start taking and looking at the effect of the speed of hydrogen, the speed of sound of hydrogen, and taking and looking at the heating value of hydrogen being that much lower. Those values, along with additional information, we can utilize that to quantify, really within two mole percents of what the hydrogen is, that's moving through our flow Sick ultrasonic meter. And that is huge if you are able to get a comparison value of two mole percents compared to what a process gas chromatograph would actually be deriving as the actual value it's determined that is moving through your pipeline system. And this information is also very critical, as one validation point to ensure that your process gas chromatograph is accurate, but additionally, as that hydrogen is blended and it moves through a pipeline distribution systems network, then the question is, how is that blending being maintained throughout that whole distribution network? And so, being able to have that kind of an indication of that mole percent within a 2% kind of value is critical through an entire pipeline system.

Larson: And I'd imagine that ultrasonic flow meter is not cheap, but of considerably less expensive than a gas chromatograph is.

Harris: Absolutely, and much, much more cost effective to maintain.

Larson: And that's absolutely true. So given the differences in some of the physical properties of gases, is there really a practical limit to how much hydrogen can be added? I mean, I would imagine that a pure hydrogen flow would would not work well, and most of the pipeline's that as they, as they exist nowadays. Could you talk a little bit about what the limiting factors are?

Harris: Sure. So, one of the important limiting factors is really driven by an organization called BAM, B-A-M, and that is the Federal Institute for Materials Research and Testing. And what this research gives us is it kind of spells out that the explosion group classification today, with anywhere from that 0%, 5%, 10% kind of numbers that we see that we would support today as an explosion group classification of something called a 2A classification. And so one, of the limiting factors is, if you are operating with a mole percent of hydrogen up to that 25-30% range, that classification then moves from a 2B, or a 2C kind of range. And so, it's because of that kind of impact that there has been significant research conducted, in really this area, for most pipelines are looking really to blend up to a 5-10% hydrogen with natural gas. Now, there is additional testing that's being conducted at that 15-20%, really even up to those 30% levels, but the driving focus that you see is really on safety, and also being able to quantify what those lower carbon emissions are for pipelines. But a key driver of all of that is all around safety.

Larson: I imagine, start at 5-10% for now, and then we can prove it out at higher levels once we have that much hydrogen to add, but certainly, safety has to be the driving force that makes a lot of sense.

Harris: It does. And also another piece of that is, how much lower carbon emission benefit do you get from increased hydrogen? And so that is what all of those studies are really focusing on is what benefit that you get from the higher concentration of hydrogen, and so all that factored in with any safety related concerns at all.

Larson: I would imagine that all the different types of burners and devices and all that kind of stuff has to be tested as well to make sure you're not getting some unexpected implications from a different gas flow as well.

Harris: Absolutely. I mean, the wobbe index, taking and looking at the heating value, all of that factors into the bruner design and what you see that is standard in homes in the US today.

Larson: I think it's to me, whenever I hear pipeline, I think custody transfer, or whether it's just needing to know how much energy that flow is delivering to its destination, because that's really what you're paying for, what you're buying, that energy. So, that means we want to know the heat value of the gas being delivered, and that means both the flow rate and the composition of that blended gas. What it is about, we touched on a little bit, but little more on what it is about ultrasonic flow measurement technology that allows this to be done cost effectively in one instrument to get that energy green.

Harris: Sure. And so, this is a question that, as really a measurement person, people talk about there being an energy meter, and it's just like what you're mentioning. We've got to know the energy value, and we've got to know the volume of gas, because those are critical to determine what is the custody transfer of gas. But in addition to that, we've got to also know the CO₂ content, we've got to know the nitrogen content, we've got to know all of the mole percents that make up that natural gas, because there are implications from a Cricondentherm-type perspective, and the inner operations of that gas in its delivery. And so, the huge benefit that you receive with an ultrasonic meter is really the ability to accurately quantify the velocity of the gas moving through the meter, and to know the exact speed of sound for that gas. And so, with that information, based on the meter's configuration, it's flowing parameters, this information provides that pipeline operator and that measurement technical operations staff the critical information to know the exact quantity of gas moving through that meter and to ensure that the BTU and the gas composition that's being derived from that associated gas chromatograph is accurate in determining what that exact custody transfer volume in energy of gas being recorded by that meter is at that specific physical point. And that is critical through all of your pipeline operators throughout their entire infrastructure.

Larson: That makes sense. Are there other advantages of Sick's ultrasonic solutions relative to other flow measurement technologies when it comes to this sort of application?

Harris: Sure. And so, if we take a look at hydrogen measurement, we've been talking some of blending hydrogen up to 30%. And, Sick's ultrasonic meters, our new latest ultrasonic meters, being able to handle up to measuring 30% of that blended mixture of hydrogen today, but, if we take in we look at Sick ultrasonic meters that have been implemented throughout the world, including the US, have been measuring up to 100% hydrogen since 2005. Now, historically, that has been classified to operate within a 2% accuracy limit that wouldn't meet what you and I are talking about as far as a custody requirement today. However, measuring 100% hydrogen has been possible with hydrogen meters for years today, and this is an area that is continuing to grow and improve to where, around the corner, we will see custody transfer of hydrogen measurement at 100% hydrogen with ultrasonic meters. But that is just not there today. You see up to that 30% As a custody transfer type classification.

Larson: But I would imagine there's lots of applications within say, a green hydrogen electrolyzer or those kind of applications where you can still do a pretty good job at 2% within those within that manufacturing applications.

Harris: Yeah, absolutely. Absolutely. And you know, what really factors into that is the volume of hydrogen, you need to measure and the volume of gas that you need to measure. And that factors directly into what ultrasonic meter and what metering technology makes the most sense for you at that time.

Larson: Makes sense. So when it comes to meters that are already out in the field, maybe had been been out there for a while, are there ways they can be upgraded, so that they're more hydrogen ready, I guess, would be the term?

Harris: Absolutely, Keith. So, if we take and we look at the flow Sick custody transfer meters that are in the field today, one key point to take into consideration is those meters are designed to handle a blend really, up to 10% of hydrogen today. And so, a meter that has been implemented in the field and has been in operation, that meter today can handle up to 10%. However, if you really want to be able to expand that, our meters are easily upgraded to handle up to that 30% blended hydrogen and provide that gas quality indicator that I was really kind of talking about before so that you are able to know, are you within that 2% of what a process gas chromatograph would indicate for the mole percent of hydrogen that's moving throughout your pipeline network. And so, we encourage customers to really have a hydrogen assessment conducted at your facility, because it is very possible and very probable that you may not need to actually perform any upgrade of your equipment at all, if you're going to operate within that 5-10%. However, if you're going to expand that, or if you've got some unique type situations, we would encourage you really to have a hydrogen assessment conducted that we can really tell you what might would be required, if any, as far as an upgrade at your facility.

Larson: Okay, great. Well, thanks so much Duane, for sharing your perspective with us today, and best wishes on this important application of Sick technology to make the world a greener, more sustainable place. If any of our listeners today want to learn more about Sick's offering in the realm of ultrasonic flow motion, where can they where can they go for more information?

Harris: Well, the best place really to go is sick.com. There have been some white papers that I have worked with our team in Germany that have been been presented at AGA conferences here in the US. And those papers have also been presented from a European global type perspective. But the best place to seek out information is really at [email protected], and we will respond to you, provide you links to those papers, answer any questions that you might would have, and we look forward to doing so.

Larson: All right, great. Well, thank you, Duane. And thanks once again to Sick Sensor Intelligence for sponsoring this episode, and to you listeners for tuning in. If you've enjoyed this episode, you can subscribe to Control Amplified wherever you find your podcasts. Plus, you can find the full archive of past episodes at ControlGlobal.com. Signing off until next time.

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