Introduction
Cameron Croft:
Welcome, everybody. This is our virtual roundtable webinar. We’ll be focusing on summer heat’s impact on processing natural gas. Thank you for joining us today. Let’s get this thing started. To stay in the know, if something happens, you have a meeting pop up, the kid walks in, the internet goes down, we will be uploading this video to our YouTube channel and this can be embedded onto our website as well. So, if you got specific questions, please reach out to us that you want the video so we can ship you a link, or you’ll see it within the next week or so on our YouTube channel. My name is Cameron Croft. I’m CEO of Croft Production Systems. We are putting this webinar together to help share our knowledge, our education with our clients to other people in the industry. So, that’s the reason I brought Chris Smithson, our director of engineering. He’s been with us for over 10 years. He’s in charge and gets blamed for everything that goes wrong with Croft Production Systems.
Cameron Croft:
So, the Director of Engineering Chris will be joining us, and then Eric Gorka is our service manager. He runs the service team. We operate in 14 states, so he has a lot of things that work with him and against him at times, but I appreciate Gorka joining us today going through. So, the topic highlights. We really wanted to focus on what our clients were asking for, so we frequently asked questions over the years. So, especially when it comes to the summer heat, so we’re focusing on the impact on dehydration, heat impact on liquid recovery, and BTU reduction. The impact on compressors, amine plants, instrumentation lines, and the colorimetric tubes. So, we’ll be going through that today, going through tips and tricks and what we’ve seen in the past, and hopefully, be sharing some gap of knowledge that y’all might not have.
Cameron Croft:
This is a round table structure, so please feel free at any time. We’re going to be going through each of these topics and I’m going to try to get them to stay on schedule, but if you have any questions, please do not be afraid to write either in the question and answer box or in the chat function. So, that way, we can get those questions answered for you. This is a virtual round table, so our whole point of this is to actually engage. All right, so we’re kicking off in today’s meeting the heat impact on processing natural gas, so the focus on this one is heat. So, the biggest thing that everyone focuses on first. Chris, if you can kick us off on characteristics of saturation.
Water Saturation in Natural Gas
Chris Smithson:
So, yeah, with heat comes an increase in water content and that’s usually a big thing that affects a lot of the different production issues that we see and so the two main characteristics of water saturation for natural gas are pressure and temperature. So, as the temperature goes up or the pressure goes down, that water can physically hold more gas or the gas can hold more water. So, we always prefer higher pressures, lower temperatures to help that out especially with dehydration applications. The lower the temperature, the less the dehy has to work, but a good rule of thumb is that for a 20-degree increase in temperature at the same pressure, you can double the water content of the natural gas.
Chris Smithson:
So, when it starts, it’s not quite 20 degrees as you get above 100, but basically, if you’re going from 80 to 100 degrees, you’re doubling the water content, which can double the amount of work that that dehydrator has to do and so that can be a big impact on the actual dehydration capability and what your equipment can possibly be able to do, but that’s a really good rule of thumb, 20-degree increase in temperature or decrease in temperature either doubles or halves the amount of water in that gas.
Cameron Croft:
All right. So, if you double the amount of water, what does that have to do with dehydration?
Chris Smithson:
For a glycol dehydrator, if you’re doubling the water content, that means you have to double your circulation rate to make up for that. Hopefully, your tower is big enough. A six-tray tower may not be able to handle that absorption. If you’re at 100 degrees and you’re going to 120, usually, that’s more called for an eight-tray tower or if you’ve got a packed tower and a taller one, but the circulation rate is the main thing. If you increase your circulation rate, if you double your circulation rate, then you’re cutting in half the life of your filters. So, if you’re changing them every month, then now you’re changing every two weeks, you’re also doubling your fuel gas usage. You’re doubling the number of pumps you have to stroke, which is going to increase wear and tear, so you’re really shortening the life of your dehydrator the harder that you’re running it and increasing the cost of consumables.
Cameron Croft:
Well, from Gorka, I mean, your service guys have to handle this type of equipment all the time. So, I mean, if you’re doubling them out of home circulation of it, what do you do to prepare your team to go out there and do better preventative maintenance?
Eric Gorka:
Right. Like Chris mentioned, everything works harder. When the gas is hotter, your pumps are stroking more. The more strokes, the more wear, and tear is going to be on the pump, so you have to be aware of… As Chris said, you might be going once a month changing filters where you got to be aware that, hey, the filters might get dirtier faster, so you always got to be checking in pretty much on the plant. One of our plants in South Texas, our tech goes down there once a week in checks and makes sure everything is working properly. You don’t have hiccups or anything like that. You got to check your instrumentation and make sure it’s working 100%. For our PDS units, it’s going to be pulling. More water enters the system. That means it’s going to be pulling more water. That means it’s going to accumulate more at the bottom. It needs to be dumping more frequently.
Eric Gorka:
So, you got to make sure your instrumentation is always running properly. There are no hiccups there. That’s just going to lead to more issues if that’s not running properly, but definitely, in the summer times, the service team is very aware to dot all the i’s and cross the t’s and make sure it’s 100% fully working properly before they leave each location.
Chris Smithson:
Yeah, and for our PDS systems, since they have that consumable desiccant that’s doing the dehydration, we sell more enviroDRI in the summer than we do in the winter just because the average gas temperature is higher for our clients especially in South Texas, someone through East Texas so that if there’s any cooling that can be done, it’s a direct cost saving if you’re using our PDS system. For glycol units, it really is just more of a work that’s having to happen, but that’s for heating. On the opposite side of that, we have cooled. So, if the gas is cooling when it’s coming into the dehy, then you have a risk of if you have very rich gas, actual condensate fallout, running into the unit. So, if you’re coming off of a compressor at 120 degrees and it’s only a nice warm day of 95 and the gas is cooling as it’s coming to you, you may have a liquid fallout that’s going to slam into your dehydration unit.
Chris Smithson:
Now, you should have good separation ahead of it, but that’s not always the case. Especially with oversized stuff, maybe you have oversized piping. Stuff builds up in low spots and then you slug into a contact tower. The inlet set on the bottom of the tower should be able to handle that, but if it’s not able to or not effectively separating it, then you’re getting a lot of hydrocarbons into your contact tower, and then that’s hopefully going to be separated out in your three-phase separator if you have one, but you’re getting that oil in your glycol. That’s what the separator is for, but you’re going to increase the usage of your carbon filter because some of that’s going to sneak by through the separator. Then this the carbon filter is not going to be able to absorb.
Chris Smithson:
The contaminant’s going to cause foaming and then you have other problems that you’re going to have to deal with, but yeah, cooling is a big thing to look out for. Making sure you have adequate separation after any sort of cooling or just putting in a cooler so that you can force the cooling to happen with the separation so that you’re not relying on your pipeline to cool it down and however X many feet of that and then cooling happens in places where it’s not supposed to.
Preparing a Glycol Dehydrator for Summer
Cameron Croft:
So, one of the questions that we have from one of our clients is right now what are they supposed to do to assess or prepare for their TEG systems before the summer months? What are some top five things that y’all would look out for right now?
Eric Gorka:
Get filters in stock.
Chris Smithson:
Yeah. I would definitely be looking at if your spare pump working because if you’re going to be turning your pump up, maybe you find out that as soon as you go turn those knobs, the thing doesn’t want to go any faster. I mean, I would definitely look at if you have a compressor, or is there anything that you can do to open those louvers. If we start to get out, the fall and spring season is always the more awkward time because temperatures may still drop low enough to where you don’t necessarily want the full open on your coolers if they’re manually operated. So, that can be a little tricky because then you get excess with temperatures in the heat of the day, but yeah, if there’s any cooling that you can potentially do ahead of the summer months, it’s always a good idea to look into.
Cameron Croft:
I guess you kept on saying proper separation before the contact tower. So, I guess making sure the liquid level controllers, dump valves, those things are being operation before that hits into the tower?
Chris Smithson:
Yeah, making sure your dump valve and level controller operate on the integral separator on the bottom of your tower if you have one. If you got a coalescing filter, maybe it’s a good time to change your filters. As the cooling happens and the hydrocarbons condense out, you can get a fog going through there, which is what [mis-lem-mares 00:10:21] is made for, but if your coalescing filter maybe hasn’t been changed in a year and a half, maybe it’s imploded, and it’s just not doing what it’s supposed to anymore. Maybe it’s a good time to change that out because it may start seeing a little more work to have to do.
Cameron Croft:
Well, we’ll move on to the next one, but you see my son on this one? Yeah, he’s our new worker. He’s already telling me what to do, so I think he’s going to work out just finding the oil and gas.
Chris Smithson:
Pumps about 10 times his weight.
Preparing Amine Plants for Summer
Cameron Croft:
Yeah, that’s right. All right. So, the reason why we’re focusing on amine plants right after the TEG system or dehydrator is that there’s a lot of functionality that’s the same, but there is some tips and tricks on amine plants that are different. So, Chris, can you kick us off on I guess an amine plant. What is it used for and why the functionality is the same?
Chris Smithson:
Yeah, so similar pieces to a glycol system, contact tower regeneration. So, the same inlet conditions apply. If you’re cooling, you don’t want to slug into an amine plant with liquids. Amine plants are more temperamental than glycol systems, so you definitely don’t want to introduce a bunch of liquid especially because the amine is a water-oil or a water amine mix. It’s a little more finicky if you’re getting the wrong kind of water in there. You get a bunch of brine water in there, then you have salt in the system. It can’t really quite separate it as well and so the impurities make more of a difference on the amine plant. So, if you have a bunch of cooling happening especially cooling inside the tower where it’s actually condensing inside the tower, that can be very problematic, but it’s the same issues that you’d have with the glycol system.
Chris Smithson:
The big difference with an amine plant is that when you absorb the CO2 or H2S, you have a heat reaction in the tower of the amine plant. So, the gas normally increases temperature as it’s absorbing, getting the CO2 or H2S absorbed out of it. So, your outlet temperature is normally a lot hotter than your inlet temperature, and what this is doing is because you’re coming in probably most likely 100% saturated into it because you’re going to be before dehydration. Then you’re going to start sucking water out of the amine, which means you have to make up more water into your plant. Now, some smaller plants, don’t have an aftercooler and a separator to try to recover that water. So, the hotter the gas coming in, then the hotter the gas coming out, the more water than it can pull out.
Chris Smithson:
So, if you’re coming at 100 degrees versus 120, that’s double the water content. So, if you can cool the gas coming into where your heat of reaction, you’re only getting up to 100 versus 120 or versus 140, but then you’re going to have a lot fewer water losses the cooler that outlet is even after that heat of reaction. So, pre-cooling into the amine plant is always good. If the amine gets too hot anyway, then it’ll stop absorbing. If you’re like you’re after a compressor and you’re coming in at 130 and then the heat of reaction is getting up to 140, 150, it’ll just stop absorbing CO2. So, pre-cooling can definitely help to get out some of the hydrocarbons and anything that may condense out of there, but Mr. Gorka can definitely speak to water losses on the amine plant.
Eric Gorka:
Oh, yeah. Yeah. Well, actually, you don’t notice it until you actually get out there and you’re like, “Oh, where did all my water go?” Everything seems to be running fine and you go and check your water tank and your water tank is low and you’re like, “Oh, boy.” That’s something you got to keep out for. Also, with the condenser, it’s hotter outside and so the condenser is not changing the steam from the reboiler to the reflux. It’s not condensing it down to the water, so you’re losing some out of your back pressure valve up top and whatnot. So, that’s some of the water that you lose. Also, I don’t know if we mentioned it earlier. I don’t just want to throw it in there that we always… A rule of thumb for my guys at least, we tell them after the pumps, the fluid going into the contact tower, have that temperature 10 degrees hotter than the gas coming in, and that helps with the cooling down that you mentioned earlier when the condensate falls out in the contact tower.
Eric Gorka:
I don’t know if we mentioned that earlier, but just a quick fun fact, I guess. That’s what we always tell our guys. Keep that fluid temperature about 10 degrees hotter than actually the gas coming into the tower. You don’t have that real cooling effect of bringing the gas down and condensate fall out, but I mean, yeah. I mean, you hit all the points really with the water loss in the contact tower.
Cameron Croft:
I mean, is it the same thing as a TEG where you have to increase the circulation rate on an amine plant, or is… I know you’re not removing water, but there might be a tendency of your better, I guess, more absorption onto it. So, is it having to work harder? Do you actually have to increase circulation rates to the summer?
Chris Smithson:
No. Theoretically no. The absorption of CO2. As I said, unless you get to that temperature so high that it’s just going to stop absorbing, then that’s the only issue with it. Technically as you boil the water out of it, you get more amine. You have more absorption capacity, but you’re hurting the plant because if your amine concentration for DEA is 25% if you boil your water out and you get up 35%, then you’re increasing the viscosity of that liquid because now it’s more amine. It’s a lot thicker. So, then your pumps are working physically harder to pump it. Your filters are probably going to clog faster or show a higher differential because it’s just a thicker liquid pumping through them. So, it can cause other problems with that. It can wear stuff out. That’s an operational thing. You really shouldn’t let your… I mean, let it get to where it’s a noticeable increase.
Chris Smithson:
Your water makeup should be making up that difference in there, but then you have to be careful. You do lose some amine as well. So, if you’re only making up water, then your concentration may actually get too low, and then you have the reverse problem where you’re down to 5% concentration or something because nobody was paying attention and they just keep pumping more water in.
Managing Temperature on TEGs
Cameron Croft:
Well, then, so on the TEG system and the amine system, are there any adjustments on the burner side like maintaining temperatures. You got higher circulation. So, does that mean… I guess you have to make the adjustments to manage the temperature on the TEG?
Chris Smithson:
It just needs to be able to keep up. So, I mean, if you’re already at max with your reboiler, then you’re going to find that you can’t turn up higher. Most of the reboilers are sized for the pumps, but for some of the sizings, the pump’s definitely bigger than the re-boiler can technically handle. So, the reboiler running at max may not be enough to handle the circulation rate that you need on a glycol dehydrator.
Cameron Croft:
All right. Is there anything else y’all wanted to add to the amine plants? All right. All right, so the next one that we were looking at was a natural gas liquid recovery or BTU reduction. So, it’s not just recovery methods. It’s also the BTU reduction. So, we got three sets right here. Your JT system’s what we’re going to be focusing on today, but you do have mechanical refrigeration cryogenic, but we wanted to go into natural gas liquid recovery on the JT side of BTU reduction, but Chris, can you go through what that means and what these charts are actually entailing?
Chris Smithson:
Yeah, so the main point is the hydrocarbon dew point. So, what is the temperature at which hydrocarbons will start to condense in your gas stream? If you have real lean gas and that’s normally not a problem. Your hydrocarbon dew point on a real lean gas, we got 90+% methane. It’s probably going to be down to 10 degrees, maybe negative 10 or something if it’s lean enough, but a lot of these shell plays are a lot richer gas. So, some of that gas, it’s so rich that the hydrocarbon dew point is whatever the temperature is coming out of the wellhead. So, any degree of cooling will cause liquid to start falling out and different components have different condensation temperatures. Because it is a mixture, it doesn’t really work that way. As soon as you get the temperature, all the butane falls out or something because it is just a mixture of it. Slowly, you take out some of the heavies, but they take some of the light ends with them, but basically if you cross that…
Chris Smithson:
We have an example of a simple phase diagram here. If you cross that temperature line, then you’re going to have liquid creation in there, which is the whole point of NGL recovery. Cool it down enough either cryogenically or refrigeration, someway you do the self-refrigeration with the JT, your mechanical refrigeration with the MRU. You want to get cold enough to recover that, but being able to get that cold is dependent on what your inlet temperature is. So, the basic idea is can you pre-cool some of that to help aid in your NGL recovery process? So, making sure your temperature isn’t 120 coming into your NGL recovery process is pretty important just to make sure that you can get to the low-end temperature that you’re trying to reach.
Cameron Croft:
All right, so when it heats up, is there a rule of thumb? You know, every 20 degrees, that doubles the amount of water saturation that could be in it. I mean, if you keep heating it up, will more propane, butane, pentane, that all the heavies, will they actually start… I guess can the gas hold more in a gas form like richer?
Chris Smithson:
It can, but it is dependent on the composition of the gas. So, if you were to have a gas stream coming out of the well and if someone’s condensing 100 degrees and you’re seeing some liquid fall out and then you go through a line heater and you heat it back up again, you can definitely have a lot of that flashback depending on how hot you’re heating it back up again. Some of it isn’t going to just stay liquid. Once you get some of the real heavies out for octanes or something, once they’re out of the gas phase, they’re going to stay out of the gas phase because they’re not going to get hot enough to jump back. They’d have to get back up 200 degrees before they actually vaporize back. So, it is like a capacity thing, similar to the water where the hotter it is, the more it can hold, but really it just depends on what’s in your liquid that you’re vaporizing out of it.
Chris Smithson:
So, if your liquids have a bunch of light ends in there, if you get it hot enough, it’ll start to basically stabilize the liquid by cooking the lighter ends out of it, which then can take some of the heavier with your peptides, octanes, hexanes, and stuff. It’ll raise your BTU with the gas.
Summer Heat’s Impact on Compressors
Cameron Croft:
Well, y’all keep mentioning compressor, so this actually transitions pretty well into this. So, this is the heat impact on compressors. Now, that’s something that, Gorka, I’d for you to kick off on. What do you see what your guys are focusing on… I know we got a lot of FCS on gas gathering facilities, artificial lifts. So, getting out there for the fuel gas or degrading the compressor. Can you walk us through what you all have to experience?
Eric Gorka:
Well, I really like our FCS. It’s I think what we call the Frankenstein of the company. It’s got a little bit of everything to it.
Cameron Croft:
Well, you’re biased. You can’t say you like them.
Eric Gorka:
They’re very simple, but I’ll just walk you through the FCS, all that it does for the compressors, and why they are so good, and I’m not saying our FCS is on top of the line, but all the parts that help out the compressors. You go in. You have up in the top left I guess there the ambient cooling system. It hits the cooler and it cools down the gas. Again, that’s what we’re talking about the whole time is cooling down the gas. So, we have that. We also have bypasses on it. So, on cooler nights, say in West Texas because in West Texas, it might be 95 degrees midday or early morning, and late at night, it’s 50 degrees and it’s just West Texas for you. South Texas, not as big of a drop, but you can always bypass the cooler. In the winters, you bypass the cooler, and I mean your gas is still cool, but then from there, you go to our PDS system on the unit and it dries the gas before it goes to our choke.
Eric Gorka:
That helps eliminate some of the methanol injection. You’re drying your gas before you take a choke. You’re not freezing up. Go through your heat exchangers to your choke valve. That’s where you take your pressure drop. Then you have the majority of your fallout right there in the cold sep, and like was mentioned earlier, to get even cooler, in one case, we took the cold sep drain and we ran I guess the liquid heat exchanger using what we were draining out of the cold sep just to cool the gas even more, and I think that was just for a few months in the summer where we’re trying to get it cooler to get the cold sep down, but then from your cold sep, you run it back to your JT. Not your JT. Your heat exchangers and then… Well, in the one picture, we do have the secondary choke up top there and then it goes out and into your compressor and it knocks out a lot of stuff.
Eric Gorka:
You hardly ever see problems with the system and the compressors run a lot cleaner. In my opinion, so why wouldn’t you have each one of these pieces of equipment, maybe not our piece of equipment, but something of this sort to help with the fuel gas for the compressor.
Gas Composition Issues
Cameron Croft:
So, you got the fuel gas for the compressor. Everything goes through a Big Joe, then Little Joe back into it. So, I mean, what are you seeing on the composition, Chris? You do a lot of the simulations and you work with Caterpillar on a lot of the engines. So, how do you walkthrough? What are the issues that we’re seeing?
Chris Smithson:
So, especially in richer gas areas, any cooling typically will make liquids. So, once you’ve compressed the gas, the higher the pressure, the less liquid it can hold. Similar to water content, as you increase in pressure, you don’t have to get as cold to recover the same amount of NGLs and liquids out of the gas, but what that means is then when you compress it, you’re going to pressure that up. You’re going to run through the aftercooler that’s built into the compressor. There’s no separator though. All those inner-stage scrubbers are just in between the stages. There’s no after-stage scrubber on a compressor or at least most of the ones you’ll ever see. So, that gas comes out at high pressure. It’s been cooled a bit through the aftercooler on the system, but they’re only really designed to output 120 degrees when it’s 100 degrees outside. This is what they’re rated for. They’re not meant to get you five degrees of ambient. They’re meant to get you 20 degrees of ambient.
Chris Smithson:
So, you have this high pressure, hot gas, that’s basically fully saturated with liquids when you have that real high BTU gas. So, any cooling is going to make liquids in there. If you can keep that gas hot and you can run it through your system, it’ll leave your location. You won’t make any liquids, but when you try to run it for fuel gas through a Big Joe regulator, it’s going to take a pressure drop, as soon as you get cooling, you’re going to have liquid fallout. So, if you can pre-cool any of that, then at least you’ll get some of that liquid out beforehand before it starts going through those regulators, which is less than likely of hydrate formation. This will reduce the methanol that you need in there because that liquid slamming through into those fuel gas separators, if that’s all you have is a Big Joe, Little Joe, and a fuel gas separator, then you can definitely overwhelm those pretty quickly if you have real hot gas coming in.
Chris Smithson:
But if you can pre-cool it in there, it’ll definitely help out on how much liquid that separator is going to get slammed with. Also, if you can cool any of that out of there, then it’s not going to be falling out in the pipes leading up to that stuff. So, sometimes, people, they don’t… They don’t even have the fuel gas separator set up on the location. They just look like little fuel scrubbers handle it either on the compressor or on the glycol unit or the burner or whatever, use those little fuel pods, and then they’ll have their regulators there. Well, as soon as you may end up with a bunch of liquid that’s cooling out of that gas as it travels down your pipe rack all the way over to your compressors and then all of a sudden turn a new compressor on, it’s been idle for a while just sucks all that liquid straight through that fuel line, overwhelms that little fuel pod and then it’s in your fuel system.
Chris Smithson:
So, managing those temperatures is really critical to making sure you don’t have hydrocarbon dew point issues, but for fuel gases, it’s pretty important. Especially with a richer gas application makes a bigger difference as to where you’re taking your pressure drops and how you’re dealing with that cooling on there.
Cameron Croft:
Well, I know you mentioned a number of time to our clients, like their aftercoolers aren’t working is properly or they just haven’t bypassed altogether. So, I guess what are the tips on that? You got the summer months happening. It’s automatic louvers, making sure that they’re actually working properly.
Chris Smithson:
Yeah, and the biggest issue we see is it’s that in-between time. It says we’re starting to get into summer when it’s constantly hot. It’s time to just leave the louvers open. Just let it cool the way it’s supposed to. Don’t try to keep it artificially hot. Some people just aren’t allowed to remove liquids. You’re not supposed to do anything that removes liquids. I mean, the aftercooler and compressor that’s built into the unit, like let it cool it down and recover it because of some of the pipeline regulations. Some of the pipeline contracts are not allowed to… The pipeline wants all those liquids so they can sell them, but yeah, anything, and the heat coming off the compressor can affect a bunch of things down the line. It’s going into an amine plant that increases heat. It’s going to suck the water out of the plant. Dehydration is going to make it work harder and compressors are the typical place we see the heat being introduced ahead of the production equipment.
Chris Smithson:
Now, we’ve definitely seen some hot wells that we’ve seen. There’s equal for wells that output 160, 180 degrees worth of gas coming off of that, and that can be difficult too especially as you try to separate. Separating 180, you’re not going to get a lot of the liquids out there, and as soon as it starts cooling more, that liquid starts to fall out in places after the separator, which isn’t ideal. A story about compressors for as far as inlet temperatures coming into them. We had a client that they got a compressor out there. We were doing fuel gas for it. Well, the compressor company was having issues getting the contractual volume that they were supposed to, the client’s saying, “Hey, this compressor is supposed to move seven million. You’re barely moving five. I mean, you’re at four and a half right now,” and they’re looking at us with fuel gas saying, “Your fuel gas isn’t good enough to run my compressor harder,” but come to find out the gas is coming in at 160 degrees.
Chris Smithson:
So, the gas is so hot coming in that when it’s going through the inner stages and it’s going through those scrubbers and getting separated out, they were liquefying a huge chunk of the gas stream just because so much of it was just liquid and vapor form coming in there. So, I mean, you can’t blame the compressor because the compressor is compressing everything it can. It just happens to be turning a bunch of them into liquid. So, a compressor that should be moving seven million is now only moving five million because of just that increased temperature. So, I mean, what’s the best solution? To be able to move that more gas. Well, you put a cooler ahead of the compressor. Cool it down, separate that liquid, and then you’re just only sending stuff that’s going to stay a gas through the compressor and so then you can move more gas through it. That’s a pretty big cooler to be able to do that.
Chris Smithson:
It’s also low pressure, which is going to increase your cost there, but that’s an interesting issue for having high temperatures that I hadn’t seen before until about two years ago as far as something that was de-rating a compressor. It wasn’t fueled gas.
Heat Impact on Instrumentation Line
Cameron Croft:
Let’s go on to the next one. So, the impact on instrumentation line. This could be instrumentation lines fuel lines. So, I guess, Eric, I mean your guys have to chew on this a lot. So, give us a bloopers reel of what you’ve seen out and how have y’all fixed it.
Eric Gorka:
Yeah, so a lot of times when we see the fallout in instrumentation lines, it’s a real rich guess. Real rich guess and there’s no knockout or anything to catch it before and it’ll be in our supply gas to either a level controller or a dump, and we’ll catch it in the regulator, and in the regulators, we’re just pulling it down saying low pressure followed by a… I’m sorry. High pressure followed by a low-pressure regulator and little low-pressure regulators got the little drains on it. Well, it’s what we tell our guys. When you go up there, open the drain, see what you have, and you’ll just have… Like you open the water hose and it’s just condensate falling out of there, and if you don’t catch that in time, it’ll get into your pilots of your level controllers and it will mess them up. Maybe not at first. It might, but eventually, they’re going to wear down the seals and whatnot, and our timer boxes, the solenoids are electronic.
Eric Gorka:
They’ll get in there and screw them up. We’ve seen it so far deep as after a level controller, it’s gotten into the dump valves and has messed up the dumb valves. You hit it or you take off the supply line and it’s just condensate coming out of the dump valve.
Eric Gorka:
Yeah. With the real rich gas, yeah, but how we try to fix it or we have fixed it, it’s been working out for us so far at first. Let me back up. When you get condensate in there, you need to change out everything. You have the regulators. It’s not going to be long before your pressure gauges no longer read the correct pressure. So, if you find it’s always in there and it’s full, switch those things out. How we caught it before, we haven’t really stopped it, but we’ve caught it before the regulators. We’ll put a little knockout chamber in front of the regulators or in between the regulators, the high pressure and the low pressure. We’ve tried different sorts, different areas to see where we’re getting the majority of the fallout in the instrumentation lines, and we’ve gone on… Some of our units so far will have so much fallout.
Eric Gorka:
We’ll take fuel pods now that we have in the yard that we’re not currently using and we’ll put that on the instrumentation line and they have the automatic shutdown. If that fuel pod gets too high, it shuts down instrumentation gas just to protect the regulators and the pilots and the timer boxes and the dump valves, but yeah. It’s a real thing to catch a lot of condensate in the regulators, and if it’s continuously a problem, find some way to catch it before it messes up your instrumentation.
Chris Smithson:
Yeah, and that goes to like don’t pull fuel gas right after a compressor. If the gas is cooling on your location, pull from the coolest spot. Your regulators are going to drop that pressure down, so you may have more impact, but you’re going to have a lot less cooling effect as if you’re taking a 120, dropping it down. It ultimately gets down 60 degrees or something. You’re going to have a bunch more liquid fallout than if it’s 100 degrees and then it cools down and you set your regulators right to where… You’re still getting down maybe 60. You’re still going to have less liquid fall out that way. So, if you get that real hot gas, then you start running through regulators. You’re going to see a lot more liquid fallout.
Eric Gorka:
Yeah, and after your instrumentation, after all the equipment, not before. I’ve seen it out there just like, “Oh, this is the only spot or this is the most convenient spot to add where we pull supply gas,” and it’s before and not just on hot gas, untreated gas and pulling when… That’s just waiting for a disaster to happen.
Summer Heat’s Impact on Instrumentation
Cameron Croft:
Well, on the tips and tricks, so it’s about to be summer months heat. So, does the heat actually affect the instrumentation in itself? Not just fallout, what’s in the line, but is there certain instrumentation that you got to protect from direct UV contact or things that y’all saw in the fail out in the field?
Chris Smithson:
I mean, most things are rated for higher temperatures and they’re going through the regulators. So, they’re not going to be 120-degree supply gas running into things. It’s really the liquids going through them that’ll… Rubber will absorb hydrocarbon. You get a condensate. It’s basically gasoline going in there. It gets in the rubber seals. It makes them expand, potentially leak or something, or they start ripping.
Eric Gorka:
Yeah, especially in your Kimray pumps.
Eric Gorka:
Kimray pulling condensate. They eat the O-rings in the Kimray pumps. They will eat them up and then you have a busted pump and you can’t figure out why when it’s only been down there for a month. If condensate gets into the Kimray pump, it’ll mess that Kimray pumps up.
Cameron Croft:
All right, so it’s not really the temperature in itself, but it’s the fallout of condensate-
Cameron Croft:
… that really fell. The liquids really hurt everything.
Chris Smithson:
Yeah, and it’s, I mean, setting your regulator so you’re not getting too cold. So, you’re staging your pressure drop or it’s a little more even, or you’re staging it and then it drops. Then it goes through a supply pod. Then you take your low pressure. Don’t just go high/low supply pod. Go high supply pod and then go from 90 to 30 or whatever. That can help out, staging it outright so you don’t even see that fallout in weird spots because if you drop too low, then you’re not going to see anything on the separation, and when it cools down. Then it starts to fall out even more, but yeah. It’s really just making sure that those liquids… Your cooling or heating is in the right spots that you don’t have the liquid fallout.
Cameron Croft:
All right. Let’s go on to the next one. So, the impact on colorimetric tubes. Now, this is a big thing just because it’s funny to hear y’all’s conversations and then everyone arguing, “Well, I got a Drager. I got a Sensidyne. I got an RAE tube,” and then everyone’s looking at each other. So, go into this. Chris, you want to kick us off on the tubes?
Chris Smithson:
Yeah, so this is a really common way to measure CO2, H2S water content, a lot of water content tubes. We go through a lot of those. So, what it is, it’s pulling a sample of gas through this little foam that’s got a chemical on it. It’s creating some reaction with whatever you’re trying to measure. Well, heat and the temperature of that reaction affect that reaction. Now, different brands, it’s all different, but there should be… If you have one of these two packs, if it’s RAE, it’s Sensidyne, Gastec, whatever, that little paper that comes with it should have a temperature correction factor for it, and what we see is a lot of people have never heard that before especially on the water tubes. Well, the temperature can actually affect the reading on it, and the way these are made, the ideal reading, that the exact reading it’s supposed to be is usually at a standard temperature like 70 degrees or something.
Chris Smithson:
But in South Texas, the gas is never 70 degrees. So, there’s usually some sort of correction factor that needs to be done on these tubes to get them to read exactly what they’re supposed to. For this particular table, I think this came from Sensidyne. It looks like their reaction was right at 50 degrees is where it’s supposed to be, but let’s say you pull a five. Let’s go on this chart. You see there’s a five water content on there. Your reading on the tube reading is a five. If it’s 100-degree gas, that five is actually a two and a half. So, the reading is a lot lower when you get into the real high temperatures. If the gas is really high, the gas is 120 degrees, when you pull it, you read a seven. It’s not actually a seven. It could be a five or a four depending on the correction factor for it, and they’re all different.
Chris Smithson:
The Sensidyne I think is the highest correction factor. The RAEs definitely have a little bit of a correction factor on them, but typically what it is is the gas is warmer. The actual reading is lower. Now, the same thing that it also applies to CO2. I believe it applies to H2S tubes as well. They have the correction factor in there as well, but the water content ones are the ones that we see the most impact on for what they’re actually getting pulled and what the real reading is once you do the correction factor on them.
Detection Tubes
Cameron Croft:
Now, there is a correction factor. I know when we were pulling it, it’s not just H2O or water content tubes. CO2, H2S, they all have a temperature correction on them as well, but for your guys… Eric, when you’re going out there and explaining to clients, operators, pumper-gaugers, even the pipeline guys. I mean, how do you all come into agreeance of if it’s intolerance or not?
Eric Gorka:
Well, sometimes, we just don’t agree, but other times, we’ll get a medium. Like Chris said, there’s all kinds of tubes out there and say four of us show up. Not all four of us are going to have the same type of tubes, but usually, a lot of times, we’ll have to explain, hey, the correctional factor. We’re at 100 degrees. There’s a correctional factor. It might not be as big as mine, but I’m also pulling less than you or higher than you either way and we get on agreeance. Majority of times it’s like, okay, well, we’ll wait till it’s cooler. In a week, we’ll come early morning and pull it to when the gas is 85, 90 degrees instead of 104 at three o’clock in the afternoon, something like that. So, always keep that in mind that usually three, four o’clock is probably not the best time to pull a tube because of this correctional factor. It’s 104.
Eric Gorka:
Well, then you got to pull out your little slip like Chris was saying, like okay, now, I need to multiply it by 0.65, and yeah, they are under spec. But mid-morning, I think you said, Chris, at 50 degrees, was it? When it started correctional factor?
Chris Smithson:
Yeah. That’s for the Sensidyne. I think the RAEs are-
Eric Gorka:
It’s a little higher, isn’t it?
Chris Smithson:
… like 70 degrees and everything above 70 degrees will give you a high reading.
Eric Gorka:
Right. Yeah, and that’s what we use.
Chris Smithson:
Yeah, it’s 73.
Eric Gorka:
- That’s what we’d use is the RAE tubes. So, that’s what the guys know like, “Yeah,” we might be pulling high. The temperature of the gas is high. So, we might pull a seven. No, we’re not really a seven. We might be more of a three-year… whatever that comes out to be, but it’s always something to keep in mind, and it is a hard conversation to have sometimes. A lot of people, are told when you pull a tube, any color is water when you’re pulling a water tube and that’s incorrect. I mean, this correctional factor, you have an injection that might be causing the tubes to misread also. So, again, I mean, sometimes there’s a hard conversation and it could get into I wouldn’t say heated arguments. Good arguments, never heated, but it’s just a conversation you have to have.
Cameron Croft:
I like it. It was a heat impact. So, when you said heated argument, it’s funny. Heat impact on colorimetric tubes. So, yeah, temperatures do affect colorimetric tubes. We’re finding out there’s a lot of people out there that don’t know that every time you buy that little package, there’s a slip inside of it that has a correction table. So, take a look at it next time that you’ll pull out. All right, so when to utilize coolers? We’re starting to run out of time. So, Chris, if you can like the power/non-power and quickly brief on where the coolers are and what they are.
Chris Smithson:
Yeah, so the non-powered coolers are a great option for low volumes. So, there’s a velocity that you want to keep through there. So, lower pressures will derate that max volume that it can do, but the one that’s pictured there, that one’s good for three million worth of gas and depending on the conditions that it’s in, if it’s in a good windy area, it’ll be able to handle more than let’s say East Texas where there’s not that much airflow, but because they’re non-powered, you do have to take into account the environmental aspects of it. So, if you’re in a good windy area, they can work great. If you move it down the road into a bunch of trees, then it’s not going to work so well, but because they have no utilities, no power requirements, they are a really good option if you can use them.
Chris Smithson:
For powered coolers, you either have electric or you have gas-powered. So, gas-powered can run on natural gas. They have a little engine on them. That is going to have more maintenance requirements because it does have an engine on it and you have oil changes and maintenance and overhauls and stuff that you’ll have to do for them. The electric ones, you got to be able to run power to them. So, that can be difficult if you can’t get power, but the electric ones like the electric ones that we sell have outlet temperature probes on them that you can control on the unit computer. So, you can set your outlet temperature to exactly what you want it to be. The gas-powered coolers with the engines, usually don’t have such fine temperature control. A lot of times you have to put a temperature bypass around them to be able to really fine-tune a temperature.
Chris Smithson:
But with the electric ones, you can set it exactly and it’ll just ramp those little fans up and down as needed. So, it can give you really fine temperature control on the unit and because you’re setting a temperature, it’ll ramp up and down as needed, which can save you some power. If you don’t need it, you can turn it off at night time and then turn it back on, which is a little more complicated with the gas-powered one, and then for the really… These coolers are good for five million, three million up, up to maybe 24 million for the standard electric ones that we have. You can always go bigger. You can put two of them out there, but the biggest standalone cooler… Then they make some pretty big ones, probably be like 40 million at high pressure that you’d be able to do before you’re starting to stack up multiple and running in parallel, and then bigger than that, if you need to cool it down or you want to get below ambient, then you’re going to have to go to a refrigerated cooler.
Chris Smithson:
So, it’s going to use a mechanical refrigeration system like a water cooler unit or something and a heat exchanger to cool that gas down and so that’s what you’re going to need if forced air isn’t an option. If you’re in the swamps of Louisiana, there’s just absolutely no airflow. You may have to go to a refrigerated system just because of the ambient conditions and the gas things or just the ambient air being so freaking humid that you’re just not going to be able to really work a power cooler as you’d expect in other areas.
Cooling Natural Gas
Cameron Croft:
On the next one, you put a quick diagram of the highest recommended areas that you would prefer cooling. So, if you can quickly go into the scenarios of cooler one, two, three, and four, and how do they help.
Chris Smithson:
Yeah, so these are optional areas places to put coolers if you’re seeing excessive heat. So, we have the well. Coming from the well, we have our initial separator. This particular one is actually low pressure coming in. So, seven million, 30 PSI, 140 degrees. Pre-cooling that before the separator is always good. If you have a cooler, you probably want a separator after it because if you’re not making hydrocarbons, you’ll probably make some water. So, you probably want something after it just to make sure that you’re not going to have it unless you’re between a TEG and a JT, that may not be so much of an issue, but most likely you’re going to want a separator after the cooler just to catch those liquids that you’re actually condensing.
Chris Smithson:
So, the first place would be right at the very beginning of things, cooling down the entire process stream if it is very hot so that everything is cooler going down. Now, if you have a compressor, like in this example, we have the compressor. We have another cooler right after the compressor. Now, that’s to take it from that 120 down to maybe 100 degrees, something more reasonable for the application, and we want to do that again right before separation. Usually more of an actual separator, not like a filter. Coalescing filter make it overwhelmed depending on how much liquids you’re actually condensing out of the gas. So, usually, you want a separator ahead of it and then you have a coalescing filter, and then another place you often see coolers after amine plants, but not all of them have them built into the system where you have a cooler right after the amine tower and then you have a scrubber after that cooler as well.
Chris Smithson:
That way, you can recover some of your water from the amine system. Like I said, you have a heated reaction, the amine plant is going to warm the gas up. It’s 100 degrees coming in the plant. It’s probably 120 coming out or higher. So, it depends on how much you’re actually removing from there, but being able to cool that down, recover that water, also just put less work on the next thing. Usually, it’s dehydration, and here, we have a TEG unit. So, if you have that 120 versus 100 degrees is going to be double the work on that TEG unit and because you have the amine plant that’s making it warm, it’s going to be completely saturated because it’s sucked all that water right out of the amine. So, a cooler after the amine plant before they put the dehy, or maybe after the dehy before a JT unit or some sort of NGL recovery. TEGs can also warm up the gas as well.
Chris Smithson:
Like Eric was saying, a lot of times, we to have the glycol warmer than the gas coming in. That way, we don’t have hydrocarbon fallout, but that’s also going to warm up the gas. Maybe not a lot, but if it is hot coming out of TEG and you cool it down, you’re going to see improved recovery on the NGL systems, the JT unit or mechanical refrigeration.
Eric Gorka:
Just to point out real fast, Chris, like you were saying earlier like the place where you put your cooler. You don’t want to put it in the trees. Another place you don’t want to put it is where the exhaust of the compressor is blowing right on it or next to the burner of the amine plant because they’re not going to do anything. You’re working in the middle of an amine plant, it’s already hot, and so you put a cooler next to it. The cooler is not going to do anything at all. So, again, just to emphasize. I guess you say the placements of coolers are very important. You can’t just throw one out there and expect it to work when you put it on the exhaust of the compressor.
Chris Smithson:
Yeah, and it’s a little more piping. Then that’s great. It’s more cooling, right? You take a piping 100 feet away to the corner of the pad. You put your cooler, run it back 100 feet. I mean, that’s just going to get you a little extra cooling there.
case studies
Cameron Croft:
Well, and then, Gorka, that goes into… So, these are your case studies that you put in. So, quickly go through these three scenarios and what were they.
Eric Gorka:
Oh, yes. Yeah. So, that top scenario there, that’s two 48-inch of our PDS systems, and if the gas was hot… I mean, when you touch the piping, you put a burn mark on you. It was hot stuff. It was about every two weeks we were going out and putting multiple drums in, and when I say multiple I’m like 12 drums, and that was like one of them was empty and half of them was already empty, and we sized these things for 45 days. That’s how hot the gas had gotten. We put in these two coolers here, and I dropped I’d say 100 degrees. It might have dropped cooler than that and I want to say then after that, once a month, we were going out there putting four to five drums in it. It dropped. Just the temperature in that gas dropping that much, the enviroDRI usage just dropped off like that.
Eric Gorka:
So, the guys were quite happy with that. They didn’t have to run out there every two Fridays to go fill it up, but let’s see. The second case there in the team.
Chris Smithson:
That was one that when we put in front of a glycol unit that wasn’t able to handle the summer time. It couldn’t meet spec anymore. So, it was down south. So, yeah, they’d be out of spec, seven, eight pounds or something just because they couldn’t turn the pumps up anymore. So, it just wasn’t able to dehydrate like it was supposed to. It would cool it down. They had a compressor that just was always 140. I don’t know why, but it was always really hot and so it just needed a way to cool it down. That way, the dehy could do what it was supposed to.
Eric Gorka:
Yeah, I do remember that now. Yeah, it was a little undersized and they had it cranked up pretty much running as much as possible and adding a little cooler. I’m not sure how far we brought it down, but just dropping it down by a little bit, they met I think right under spec, and they were happy. Oh, and then they got the SCS. I mean, that’s what I hit on earlier and that cooler. I mean, it helps with the fallout with a JT. We come sometimes in at 160, 140 degrees, and then that’s cooler, it helps the JT drop out more or the choke valve drop out more into the cold separator. You get more fallout and compressor engines run better.
Cameron Croft:
Well, we should have done a bloopers reel because we’ve seen a lot of, I guess, the resourceful way of where they’re adding pipe into a natural ditch that’s already there and they’re filling the ditch full of water and they’re trying to cool it off that way and they’re having to pump more water in every single day.
Eric Gorka:
Oh, yeah. You see that more often than I thought I would see it. You have pet turtles. Every month, you go out to your gas to liquid heat exchanger, which is your pond and you have your little pet turtle that comes in and visits you and what not, but yeah, you actually have that. I mean, there’s one way to cool down the gas. I don’t know how much it actually does cool down, but-
Cameron Croft:
We were on one location a few years back and they actually… It was an ambient cooler at an angle, but they had no roof. So, that radiant heat coming from the sun was actually warming it up. They were heating it up. It was coming in at 120 degrees into the fan and it was leaving at 130 to 135 out of it. So, they were actually just heating it up.
Chris Smithson:
One of our clients, I think they doubled the volume to the cooler, so it wasn’t cooling. It was one of the non-powered ones and so it just wasn’t cooling as much as it should. So, they put a sprinkler on it. They just aimed a sprinkler at the cooler to cool it down. So, just dribbling water all over the thing constantly. I mean, it worked, but it’s [crosstalk 01:02:06] to keep the sprinkler on all the time.
Eric Gorka:
Yeah, I’ve seen another one where it didn’t have a roof like you were saying, Cameron, but someone’s idea was to wrap it in a tarp to get the heat on it, and I was like, “There’s no wind flow through it now.” So, I don’t know if this is going to work exactly-
Cameron Croft:
It’s dissipating that heated all in.
Eric Gorka:
Yeah. I was like, “Hey, you know what? Let’s try it. I’m up for new ideas.”
Cameron Croft:
Well, next time, actually, that would be a funner thing. Actually, tell your team start taking pictures of resourceful ideas out there so we can have not a bloopers reel, but what everyone’s trying to accomplish out there-
Eric Gorka:
Thinking outside the box.
conclusion
Cameron Croft:
… because they understand that the heat is an issue. We are going into several months and it does have an impact on their operation. So, they’re trying the best they can out there, and then hopefully this webinar is going to help as much as possible. Let them get some ideas of how they can stop that, mitigate a lot of those risks. We’re going to wrap up this, but if you’re interested in being a webinar speaker or know someone that would like to be a good fit, please reach out to [email protected]. The one thing that we like about our company is that we constantly love feedback. So, please, you’re going to get a survey via email after this. Tell us how we can tailor and improve the upcoming webinar.
Cameron Croft:
The whole point of this is to share the information, get our industry as educated as possible on best standard practices that we have. So, please fill that out. Another one is let us know if you would like… This is considered a professional development hour. So, if you need those hours, let us know so that way we can ship you a certificate if you’ve joined us today. If you have any questions, concerns, you want to run simulations, you’re having some heat issues, BTU reduction, fallouts, dehydrators are not working, not performing, please reach out to me, reach out to Tori Valigura, or you can just go to our website, click on it, and then we can get that information over to you.
Cameron Croft:
So, Gorka, Smithson, thank you for everything for joining us today, spending the time with us, and everyone that’s joined us on the webinar, thank you for joining us. If you do have any questions or follow-ups, driving home you start thinking some other ideas that you have, please reach out to us, so that we can get those questions answered. All right. Well, y’all take care guys. Thank you.
