Natural_gas_dehydration_roundtable

Roundtable | Natural Gas Dehydration

Introduction

Cameron Croft:

All right everybody, if you are just now joining, is on this webinar, this is the virtual roundtable and we are going to be focusing on glycol dehydration, we will be touching on a few other forms of dehydration but mostly focusing on glycol dehydration. Let’s get started on this, there are four main areas that you see, if something goes wrong it is okay. I know a lot of people are working from home, the internet goes out or a child walks in. What we are going to do is we are going to be downloading this and then of course uploading it to our YouTube channel and our blog. If you want to do a transcript or do a switch quick control search to find out exactly what we are talking about, we are going to be posting the transcript along with the video as well. Let’s jump right into it, I want to introduce the speakers, my name is Cameron Croft, and I am the CEO of Croft Production Systems. I will be playing host today for the webinar. I have my director of engineering Chris Smithson joining us today. Christ Smithson runs the engineering teach for Croft Production Systems which is a natural gas company, co2, ho2 rejections, dehydration equipment, and JT recovery and knockout. Then we have Jesse or Jesus Olivares is also joining us today. He is the CEO of Osynergy, he has worked for several companies in the past, project management, and engineering manufacturing, so we utilize him quite a bit especially on the ASME codes. He is a genius when it comes to that his son and the team that he has put together. Focusing on a manufacturing perspective longevity equipment. Then we have Terry Nelson who is the manager of Technical Services for WPI, he has been helping lead the charge on the building that visions out TG services and dehydration cleanouts. He has come a long way over the last few decades anytime we have any glycol issues, TG issues, or even processing issues I like to call Terry because he has a wealth of knowledge and a lot of funny stories to set the point across. He is also going to be joining us and leading the charge on a lot of these conversations today. In today’s outline, we did reach out to quite a few people trying to figure out what are the big issues that we are seeing, and we have narrowed it down to four common denominators. One of them is winterizing, making sure the glycol systems are functioning and that it is maintaining glycol maintenance, what is proper maintenance, efficiency gains, and filtration and then the fourth one is emission controls. To get started on this I am going to discuss the round table structure, everyone that is joining us as an attendee this is your time if you are specific questions that you want to know or want us to elaborate the conversations on. We are going to allow the conversation to keep going but please the question in there. I opened the question-answer and the chat function. You can put in what questions you want us to elaborate on and we are going to be answering that as we go through each section. So, focusing on today is the natural gas containment in the water vapor of course is dehydration.

Winterizing

Cameron Croft:

So, the first topic that I want to discuss, or the common denominator is winterizing. What I want to do is kick off the question of what are the main things that you should be looking out for especially in Texas. Like in this picture of south Texas, it does not look like that but during the winter. It can hit 80 degrees in the day and then drops 30-40 at night also there is always that huge volatility of temperature with ambient swings. What would you all look out for in this, what are the failure points?

Terry Nelson:

You are going to have a lot of condensates fall out of the fuel gas system, you have got to keep that fuel gas pot drained constantly. Always check your fuel gas system because the temperature changes at nighttime will get a lot of distillates in your fuel gas and that can cause everything that you see. The top of the steel column is so black, it has a massive amount of soot so evidently, there is a fuel-air mixture problem with that burner system, they need to address part of our winterizing that we go through at WPI, with our customers, it is the burner checks. When we get that burner we take it apart, clean the burner out, clean the flame arrester and if it has a burner management system, we make sure it is functioning properly. We make sure that the Camry pump is running and functioning properly to put off waste gas, or you will have a lot of excess pressure on your pump gas separator, and your flash tank, it will cause issues and one of the things is the color of the glycol in the sight glass. I cannot see it from here built I assure you it is black because the hydrocarbon is contaminated.

Chris Smithson:

The pump gas separator does not make oil in the summertime. If you are not catching anything and there is nothing to skim off, we often see people plug them. Everybody needs to make sure the level controllers are working and then we know when it does not need to get used. When it finally starts to get cold, and you start catching some condensate in the towner then the system is not working. The right dump may not be operating correctly, or the level may be set wrong on the separator, especially the smaller flash separators, sometimes it can be a little trickier to set the level controllers on.

Jesus Olivares:

The insulation is properly sealed and this one seems to be in a decent condition, but make sure you hold on to all the heat and you are not losing it here and there. Terry and Chris already mentioned a few of the other details, especially if you are not changing filters. Terry previously mentioned it can contaminate your glycol and therefore your system is going to be operating a lot more than what it was. Most of them nowadays or all of them, should have some type of preheating into your fuel system to make sure you do not get condensation in your fuel, this is potentially some of the issues out there, what are you seeing is a lot of flashing, therefore, it results in burning up there as well.

Cameron Croft:

Chris correct me if I am wrong but there was one time that, I do not know what type of insulation they utilized but with the temperature swings, the heat would drop down and cause the insulation around the reboiler to start condensing and get wet and then almost became a conductor. There was no insulated at all it was just soaking wet.

Chris Smithson:

We have taken them apart before and found that the insulation was pretty wet, It had a bad seal on the system and this one has no flash separator and has pretty consistent coverage. You worry a little bit about where the steel column is as far as where your insulation might be, especially how they put that neck-on of insulation are the steel column. Sometimes that can stretch and wiggle a little bit and then if you get water within it that can result in something bad, a lot of times that foot where that flash separator sits on the smaller reboilers. Sometimes that area can have silicone and could break out and the water starts to get in there. Once you get water in there the insulation has a very high temperature. Insulation is comparable to a fiber material, once it gets wet unless it dries out it will lose all its value.

Cameron Croft:

The big thing that is being said is during winterizing the temperature swings are going to happen. The liquid hydrocarbon fallout is going to start happening more frequently.

Chris Smithson:

Most people start turning up the methanol in wintertime and glycol units because they are taking out the water and the methanol will get absorbed into the glycol which is an issue. Sometimes we do not see with our PDF systems that the methanol goes straight through them. It can create issues reading the tube on the back end, but the glycol system is absorbing the methanol. If you have a charcoal filler the charcoal filter will absorb the methanol. If there is an issue in the wintertime it can be caused by the methanol being absorbed by the charcoal filter. Charcoal filters have no more capacity to be able to absorb the other hydrocarbons that may be caused by fobbing. Terry, you might know better, but methanol is not a foaming issue that you may have in the reboiler it should just boil out and vaporize. Anything that is vaporizing has the potential risk of falling.

Terry Nelson:

This unit here would not be a problem because the methanol would flash off and escape into the atmosphere. One a closed system where you would have a test unit, the methanol will increase so will the flash which will have a pressure build-up in the system, and it can cause you a build-up and have some relief valve issues but normally it is not that much, but it also depends on the use of the methanol. Some people do not realize how much they are injecting, and they are dumping an excessive amount of methanol in there. What people must realize also is that the camry pumps have no lubrication. They are lubricated by the glycol going through, but the methanol and hydrocarbons are not lubricants, and the more your percentage of glycol drops. The less lubrication you have on those pumps and can shorten the life of the glycol pumps because of your hydrocarbon content.

Cameron Croft:

You are talking about liquid hydrocarbons and foaming issues. What are the main typical causes for foaming in a contact tower well?

Terry Nelson:

I am going to say hydrocarbons salts are bad. The chloride levels of that are in the glycol. The chloride levels of that are in the glycol. I tell my customers to please tell me you are doing regular sampling and you should be able to look at the glycol sample and check your hydrocarbon content for the PH level and your chloride levels. These are three things that are going to affect foaming. Most things make glycol foamy and that is not necessarily a bad thing. Frothing of the glycol then expanding surface area helps the gas and glycol come in contact and help dry the gas. When you pull a wet glycol sample coming back from your tower it is going to be foamy because it is a mixture of gas and glycol, but it should settle to a solid-fluid in 45 seconds or less that is the stabilization test of your wet glycol. I have pulled samples before that look like shaving cream and two or three minutes later it still looked like shaving cream, which is foaming glycol and that is going to cause you to lose glycol over the top of your tower. Foaming is not necessarily a good thing, but it is not the worst-case scenario. If it settles to a solid-fluid in 45 seconds that is what the laboratory does, when you send a glycol sample in, they make it foam and then watch it settle down. You can do it in the field as well. For example, you can take a sample container like a pyrex glass and pull a sample of your wet glycol, set it on a skid and watch and see in 45 seconds or less it if is sold fluid.

Cameron Croft:

This comment states are the heavier components the usual suspect's c4 pluses when we talk about liquid hydrocarbons? What are the usual suspects?

Chris Smithson:

Yes, it is usually going to be heavier than c4 would be butane. Butane really should not be absorbed in the glycol. Some of the heavier hydrocarbons are like your c8, c9, c10. When its condensates it will pull some of the lighted stuff with it. That is part of the benefits of a JT unit. That is why people can get a cluster of propane out without getting to the temperature that propane would normally be at as a liquid, the heavier stuff can pull some of the lighter stuff with it but normally you would be looking at more of the gasoline level components that are going to be able to condense in the tower. A component that is going to stay a liquid at approximately 100 degrees under pressure so technically it is more like c6 and c7 and that is getting through there and to expand the foam. The foaming is mechanical foam. When Terry said you saw the chemicals turning into shaving cream that is more likely a chemical foaming. That can keep that form as a foam for much longer so typically if we feel it and it feels off then maybe it is not right. Something may be causing that which that usually just falls out quickly, but some sort of surfactant may be causing that to occur. Soap sticks and liquid surfactants that are used to lift the wells and detergent that is in the compressor oils. Most compressors run the same oil and the compression and the engine side, there is usually a detergent additive in engine oil and that detergent is a foamer. It helps lubricate with the engines, but it does not assist anything else once it gets sucked up in the gas, detergent oils can create foaming problems.

Terry Nelson:

When I started working for xterrain and I worked there for 17 years, one of the first things I did was go to the compressors managers and ask them if they are using high detergent oil. I had to stop it and find out what the gravities of the oils were before continuing. You would be amazed what people inject in a well stream from the wellhead to the dehy and if you look at a location or a flow chart of a well, you will read the drop in soap sticks they are injecting anti-corrosive agents and all kinds of stuff from the wellhead to the very end of the line where it goes into the sales pipeline and the last vessel is that contact tower. If some people do not have a coalescing filter separator to capture that stuff and when you are injecting corrosion in inhibitors and all these different chemicals scavengers are the only way to get back out of the gas stream because we are atomizing it when we are putting it in, so we are making it attach to that gas molecule to do its job. The only way to get it back out is to put something in the pathway with a micron smaller than that so you know with lube oils and materials. You have to have a .3-micron filter to capture those lube oils and a lot of times they either do not check the filters or do not have the right filter elements and that is where consulting with somebody would help you. People wonder why their glycol is staying nasty all the time. You must have something in the pathway of that gas stream to stop that chemical flow. I mean you injected it in there, but you got to get it back out if not you will find it in your glycol samples.

Cameron Croft:

While we were talking about the injection, Javier asked a question for us. He said everybody does things differently but where are you typically seeing methanol over-injection upstream or dehy the tower is primarily in compression?

 

Chris Smithson:

Usually, the primary injection point for methanol is going to be right at the wellhead just to make sure that they are covered wherever they are going. That is where we’ve seen instances of injection was at that point of the well. The reason there is just way too much going in is they put it right before where they have a problem previously so for example, we have seen freeze-ups in Pennsylvania right before the dehy vessel was supposed to be there. The dehy unit made it all the way up there and it froze just before it was supposed to be there. Most likely because it was cooling after the line heater and so that just happened to be the coolest point before the actual dehydration. We have seen it where people are injecting 10 gallons a day of methanol and a million to two million worth of gas a day. That is just because they had a freeze-up, they set up the pump and finally set up everything. The closest injection point ahead of it and they are over-injecting because they are compensating for a problem that they previously had. For hydrates, you are more likely to have a hydrate at a higher pressure than a lower pressure so if they are injecting it, a compressor will knock out a lot of the methanol and it’s got a bunch of scrubbers. Everything else within there can still carry through the gas. If they are injecting after compression is usually the place where you need more. They have to get it and they are going to it right after. The other equipment is usually not right before a dehy unit.

Terry Nelson:

It is not just methanol; a lot of people have set their injection rates and then their flow fate change and they do not change their injection rates. You have everything going into processing say 10 million cubic feet of gas, and then your flow rates drop off the injection rate of chemicals that should also fall off with it, and many times they have got these bulk tanks sitting out there with the pumps hooked up to them. People are injecting scavenger, corrosion, inhibitor, or methanol and when their flow rates change them. They need to go back and adjust the flow of the chemical, instead of over-injecting because of that.

Chris Smithson:

An abundance of chemicals have methanol in them as well, When we run scavenger we have methanol in the scavenger with corrosion inhibitors will have methanol was added into it as well. There may already be methanol being injected throughout the year even if not the usual winterized blend of the chemical. The winterized blend has more methanol in it, but you may already have methanol coming into the system.

 

Glycol management

Cameron Croft:

To continue we are going to start on the new topic, Glycol Maintenance. We have a series of questions coming through and I know we talked about it in the previous section about filtration proper glycol maintenance, but I want to recap the tips and tricks you all have for proper glycol maintenance. Chris, do you want to kick us off?

Chris Smithson:

The biggest factor is changing the filters. I am a big fan of a colorism filter ahead of the system. As Terry was talking about it before, if you have detergent or compressor oil, one micron is not going to be able to remove that even a standard horizontal. The filter vendor is calling a 0.3 micron may not even remove it if it is a cheaper filter. I mean filtration is going to be an important part of the first step of maintenance. Look at the unit to see how it is operating, see if there are any red flags but if you are just doing maintenance the filter should be changed and checked regularly.

Terry Nelson:

I went to a location site a few months ago and the guy was upset because he was going through so many glycol pumps, so we met on location and of course, you know I always say have your operator meet us there. We started looking at the filters and the first thing I do is look at the y-strainer if there is one. We open the y-strainer up and the screen was gone, and I knew it was going to be gone they are always gone. I asked the operator where is the screen because it was gone, and I knew it was going to be gone, they are always gone. I asked the operator where is the screen? He stated with a straight face I took it out because it kept getting plugged up. The only job it is supposed to do is get plugged up. They have a canister with four filter elements in it and there were only three. So, there was an open hole after I started to see the picture here as to why he was going through so many glycol pumps, because there is no filtration going on and that pump has a very tight tolerance between the piston and the cylinder. The friction meets temperature, and the temperature will burn up and scar those cylinders and soon it will not be pumping correctly. As Chris said before changing the filters is very important. Also, the best part of what he said was the quality of the filter. Filters are not an expense they are part of the process; it’s just like glycol. Do not try to find the cheapest formulation of glycol, you know the reason we use triethylene glycol is because of its flash point and the way the hygroscopic properties absorb the water. The reason we buy a good filter element is that if it says 0.3 microns, it is a true 0.3 micron all the way through. I tell people occasionally when you are changing filters, take that filter and saw it in half, and look at it. See if it got dirty all the way through that element or if it is plugged up, you will know the first half-inch through that filter element.

Jesse/ Jesus Olivares:

By far the most important piece is filtration, and what I would look for would be any leaks. I mean if you have leaks happening you have problems. You will then have to continue looking at your piping systems and looking at your reboiler. We received a dehy one time that I do not think it was ever opened for the life of it, I mean it was worse than the pictures you would be showing here in a little bit. It had contamination, it was black and had a lot of calling and the paw rings did not exist. The part of the maintenance is to at least be able to look if you have any leaks or coloration happening. Then you need to be looking at all the details with your filtrations. The reboiler and whether it is heating and maintaining the right temperature and what is on the steel column and then moving on to your contactor.

Terry Nelson:

People realize if you have a leak, you are also sucking air in the system and the glycol in the presence of oxygen becomes very corrosive.

Cameron Croft:

We have a question coming through, it says I have seen several combinations of locations for the charcoal sack and one of those long skinny water filters. Typically, I have seen it on the sock and charcoal downstream with a pump gas separator, which works fine however some places do and some do not add the water filter on the rich return side of the glycol pumps. It is good protection for the pumps, what do you all think?

Chris Smithson:

The one he is talking about would be that we have labeled as a particular filter, 75 microns. The one right after the contact tower, so we do not ship a glycol unit that does not have that filter on it. Unless we are specifically told by the client that they do not want to protect that kimray pump. I do not know why so glycogens do not have them; I mean it is labeled as an option for most manufacturers, but I think that one is critical to keeping the kimray pump working. I mean a strainer can help but the strainer is minimal in my opinion, having that filter there is very important to protect that kimray pump. Also, there is another pump on the other side that goes into another inlet, into the kimray pump to make sure that if you get degradation products in the regenerator, you can get solids created or flakes and burnt stuff that goes through, and it will have the same scratching problems that will ruin the seals on the kimray pumps coming through the lean side even though it is supposed to be clean.

Terry Nelson:

I tell people all the time if you want to know how good your filtration system is doing, just take two mason jars and some coffee filters and take a sample of your glycol after your filter and pour it across that. Just set it aside and let it dry out, you will begin to see paraffin start to form with staining and some particulates gathering up on that filter, look at the activated carbon and the particulate in line with each other. I have seen them both ways, I have seen some people say they want to put the particulate so that you do not get the particulates and the carbon in it. I have also seen people say that they want the particulate after the carbon because some of the fines from the carbon can make it downstream, so it does not matter either way. I have seen it both ways and, there is no right or wrong. It is just different ways but the most important is the filter after the tower before the pump, because everything in the glycol that is not glycol came out of that contact tower. The dehy unit does not create dirt, all the salts, dirt, and hydrocarbons came in because of the coalescing filter. If there was not a coalescing filter or it has not been changed or changed properly it would not catch any of the particles properly or they are not the right micron for some reason. If you had a separator, you could carry over some produced water into the contact tower because possibly the separator was not sized properly, or the controls were not set to the correct settings. It carried over produced water and that produced water that makes it to the coalescing filter and into the contact tower. The glycol’s job is to absorb the water, it makes its way through the reboiler where we flash off the water, but all those particulates and solids stay behind in the glycol string unless we have a filter to catch it. If you have hundred-micron filters on the dehy, you are not catching anything you have the right micron for the contaminant you are dealing with.

Cameron Croft:

We had a question come in here, it says are you not worried about the rich filter pressuring up ahead of the flash drum. Could hydrocarbons and the rich glycol gas be in the housing?

Chris Smithson:

That is a concern if you have a filter clog on one of your little plants. If the glycol pump-out filter clogs up too much the pressure is going to drop on the downstream. You have a differential across the filter, if it clogs completely, it will clog off the whole housing. It is a high-pressure housing so it is designed to do whatever the contact tower is designed to but if it is not changed regularly, it will just stall your pump-out. The reason we had it happen on ours is that they switched to the wrong d-foamer and they got a deeper d- foamer that turned to jelly in the aiming plant. The whole thing caked up with what looked like yogurt. That filter is a very important element to keep clean. Like Terry stated if you could choose only one place to put a filter in this whole system, I know Terry would probably agree to put it before the kimray pump. If you keep that one changed, it will keep everything clean further down the road.

Terry Nelson:

I have had so many units, when we go and clean a system and we tear it apart and look at it, we pull the tubes out and look at the bottom of the reboiler under the fire tubes, and there are three inches of solids. The customers state, “Where did those solids come from?” and I say that I came into the contact tower with the gas stream. We have got to remember gas is coming out of the ground through the good bore and we must put sand separators on it sometimes to capture the sand. The gas is brought solids, hydrocarbons and with that, it is bringing water. Also, anything else could have injected itself in there. That is why the coalescing filter is important and the particulate filter on the glycol stream is critical to have. You must make sure it is the right micron and you do not have it too tight because then you will have to change it every other day, but you want it where it is catching the big stuff right then you put a smaller particulate filter on the suction to the pump to capture anything that might be coming out of the reboiler itself.

Chris Smithson:

Let us jump back to Javier's comment, he is talking about where the carbon filter ends up in the stream of things. The carbon filter needs to be after the flash separator and if you are not doing this, it is not worth putting a carbon filter on a glycol unit that does not have a flash separator. If you have oils and condensate and they are coming through the system, they will just completely overwhelm the carbon filter. So, it does need to be after the flash separator or else you're just using carbon. One thing on the small glycol units, the heat exchangers do not do a Preheat and then go through the other filtration separators as the bigger ones do. The bigger ones preheat through the part of the exchanger and then go through filtration. This separator in the filter goes through the main heat exchangers than the reboiler. The smaller ones that use the plate-style exchangers just go straight to the heat exchangers which is not great, they do not quite get the same temperature reach and then they throw a charcoal filter after the flash to separate. It gets hot in the flash separator which theoretically would aid separation because you're going to flash a lot of the oils instead of keeping them separate from the liquid. Keep in mind a carbon filter will not operate in absorb past 160 degrees. I think the type of carbon and, I am going off of what a charcoal vendor told me but some of them are lower than that, once you get past 140 degrees the absorption starts to beat the decline on it, if you are going to 180 degrees to 200 degrees through a charcoal filter it is not doing anything. It acts as a particulate filter, if your particulates are big enough to get caught in it is not doing their job. The job is to absorb the impurities, heavy hydrocarbons, and heavy metals, anything that may cause the worst type of foaming.

Multipoint inspection

Cameron Croft:

To keep up on time, what I want to do is go to the third section that we have period Terry was in a very giving mood, so he gave us what his multipoint inspection does. Terry, if you do not mind walking us through what you have here.

Terry Nelson:

This is what we send out to customers to use, the technicians use it as well, but it is a good tool to have. If you have a customer that is calling you about a troubleshooting issue with a dehy, you can send them those tools and they can fill this out you can both look at it and speak intelligently about the same piece of equipment. You will not have to ask all the redundant questions like what your inlet temperature is, what color is the glycol in the sight glass, it seems like a very elementary question, but it is critical because it tells you a lot about the condition of the glycol and the condition of the filters. If the glycol is dark and black that is not good because it should be clear to amber, once it starts getting blueish to black there is a charcoal issue, there is a problem with the contamination of the charcoal. This results in a filter issue, something is going on with the systems you must go through and figure that out. The cleanouts should be every four to five years. We state that on there because most of the time that is what you want to do. I have some customers that clean them yearly, some people believe that, and some people do not. We used to run reclamation units constantly and we had customers that swore bombs, others that did not, but it is very important to go through a consistent checklist. The reason we use this is the same points every time we are checking everything, every time we just make sure it is functioning properly.

Cameron Croft:

The quarterly TG samples, do you have customers? I don't usually ask our clients, but I know they are wheeling and dealing and being busy but quarterly samples, do you see them actually pulling those samples and analyzing them?

Terry Nelson:

It is a pacer made by cimarron energy called the pacer unit. It operates in a vacuum, and it cleans and recycles it and then blows it back in the unit. It is a distillation system, so it is cleaning the glycol and putting it back in the same system, you do not have to shut the whole unit down for a normal cleanout, you are just shutting it down. Shutting everything off and cleaning it for a reclamation, you back the trailer up to the dehydration unit and hook it into the connections where the glycol goes into the steel column, and you are recycling it back to the reclamation and then putting it back in the dehy while it is in service, and the bloat cases count the dumps that it blows cases off. If you know how much the blow cases are put out every time, the counter tells when you have turned over the complete amount of glycol that unit holds. Reclamation on a little small unit like a 500 you could do in a day or so but, the big, large unit you would have to have it running for days to let it reclaim that glycol in the system, and when you are done your glycol is clear like it was when you started. Now the problem with it is with the reclamations always cleaning the glycol. You are not moving the solids that are under the fire tune right and you are not getting the solids out of the tower. When you move that reclamation unit off location after a couple of days, it is going to come right back to being where it was if you did not get the contaminated products out.

Chris Smithson:

I mean it depends on how that unit was built originally, I mean there are certain areas of corrosion on them. Jesse, I know you have seen these certain things that should not be as thin as some manufacturers make them. Certain units that show up have no filters on them for some reason when they left the original manufacturer with the unit, to receive proper filtration you have a good coalescing filter, proper submicron, reverse flow coalescing filter ahead of your glycol unit and you are running low micron glycol filters and charcoal filtration on your system. You are keeping your temperatures in check and not letting your reboiler temperatures get too hot to where you are seeing degradation products with glycol. You can run for the same unit without having to do a reclamation or cleanout for up to ten years or so but, if you are replacing the parts properly and keeping the filtration properly is the most realistic and theoretical. You could purposely run a glycol unit if there was no corrosion that you should be worried about. Physically to continue running it you need to change out your glycol, which the reclamation, it is getting rid of the degradation products and that is a big point. I mean it is a large filter to clean the system out, but if you are not overheating your glycol which is a very tricky thing to do, especially on direct-fired reboilers because the fire tube film temperatures can get hot enough to where it is fully degrading little bits of glycol. If you get standard glycol over 105 degrees, it is going to start degrading and build up. The build-up can turn into goo or chunks that can clog up filters but if your filtration is removing the degradation products the reclamation is going to get rid of all the bad TG and leave you with just the good TG in the system. You can keep running the same system repeatedly for years as long as it has a good maintenance cycle without having to do big cleanouts. Obviously, facilities dehy’s are not subject to the same abuse that the field dehy’s go through, the facility guys are there maintaining the product they have, they see the same units every day and understand how they could work better. The field operators may change those guys out every six months, so they are just not someone standing next to that glides all unit all the time. They are just so much closer to the well like Terry said there is just so much stuff that could come into that unit when it is back in the field. There are many problems because of the higher co2 levels that you would not have to deal with further down the line or maybe even some h2s that nobody thought to check for corrosion inhibitors that are not wrong. Field dehy’s mean they may not last nearly as long just because they are not maintained as well also, sometimes it is a cost thing too. You can pay to have more filtration or the WPI to come out every month and do good service to it for you. The last option is a bad one and it will save a lot of money, but you do not have to get it serviced and the unit will just implode.

Terry Nelson:

It is critical to maintaining the unit, I tell people all the time that a lot of times I must teach customers to maintain their systems, so they do not need us as often. We used to have about 35 units in Odessa that we did monthly maintenance on, every month filter changes, and we did this 20-point checklist everything, and that way they had predictive information. We do not do that anymore because we taught the operators to do it and they take care of those units now. The charcoal filters and materials like that are critical because that is going to tell you the condition of the system. Keeping those filters changed is key. I have seen units that run forever. We just cleaned one the other day that was built in 1976 or 1977. It has been out there for 30 to 40 years by itself. It is just plugging along with the same reboiler, same fire tube, same contact tower but the only thing that has changed is the glycol filters and pumps, just the consumables.

Cameron Croft:

Jesse, I mean we have shipped several towers for you to repair and get back into working shape. The oldest ones that we have shipped to you are the early 1980’s or something close to that. The structure pack and trays are just to see if they maintain it, ripping it open to see if there are some issues with that.

Jesse Olivares:

I think by the time When I got there obviously there was not enough maintenance or checking. I like what we are seeing here and especially what Terry has is if you start with these conditions and you are monitoring over time then you are going to know when something changed. If the people in the field understand why you know something is running in these conditions and if your temperature is going higher than how it affects your blood cost circulation and regeneration etc, then your equipment is going to last a lot longer but if you do not know or they are not trying to understand. The customer should be monitoring and maintaining the system. The customer might not be paying attention to it so by the time we get to it, it is in bad shape. I think the worst pieces that we have seen the issue is around the reboiler side. We have done contactors, but I mean for the most part contactors could have been something that was just overlooked or not done right from the beginning. Sometimes you will see that the trays were just plugged and had a bunch of corrosion because foaming of hydrocarbons circulating through the reboiler. The reboilers for some reason are doing a large amount of work trying to take them apart, pull the tubes out, and kind of monitor how things are internal. The other piece is the insulation side, if it is not sealed and that insulation absorbs all that moisture and holds it you will start seeing all that getting corroded. I think it all goes back to resources; it is a very good tool to have because you can start monitoring each piece of the dehydration system, where it should be and where it is at, and then if it is not where it should be it could change from the weather or the original manufacturers or design condition. You can have issues with some equipment or get an error or have contaminated glycol. I think this is like having safety systems in place. If you have a high-level boom, you get an alarm and alert. This is excellent.

Cameron Croft:

Tony Brown said he has personally worked on glycol units as old as the 1960s, but that is with proper filter and cleaning, so he has that caveat in there. Drew Gibson, this is the last question for this section he said, “I see under item number 17, the change date of the charcoal canister is there is a frequency of replacement that you recommend?” “Do you see many customers pre-washing their carbon elements before putting them into service?” Chris, you talked to several vendors on that can you explain how you go about it?”

Chris Smithson:

The pre-washing of the carbon element is the only reason I could see it doing that. If there are carbon fines like tiny bits that may have sheared off just from shaking the canister around or something, the idea would be to wash those off, and really you should not have any contaminants that are there on the system. The canister should be clean enough that you are not going to introduce anything negative into the system. The carbon fine is the only thing I can think of that may be a concern of why you would want to do that. I would not see any reason to do that if there is a filter after the carbon filter. That is the typical way that we build them. When we build them, we have the carbon filter then we have the particulate filter right after it, I mean those like the Jonelle or Pico canister type ones with loose charcoal in them. Jonelle or Pico canisters are like the inside of a cotton sack which should not be left there. They could if they were small enough, but I would not see that as a big concern to have to do that. It should get picked up if they are going straight to the reboiler after that they may end up in the bottom of a reboiler, or build-up in a heat exchanger or something which made it a necessity to clean out.

Cameron Croft:

When would you change them out and what tells you the frequency?

Chris Smithson:

I know Terry talked about it as the simplest. The way to do this is to pull a sample before and after that charcoal filter. Put the samples into a small glass jar and shake up both and look at the foam heads that you get on top of both of those samples. If you have a noticeable difference in foam on the inlet sample versus the outlet sample the charcoal is doing something correctly. If you shake them both up and they both have foam equal amount, that is not falling like it is supposed as it should just settle away then the charcoal filter is not doing anything anymore. Pulling these samples and changing them could allow you to figure out the optimum time to change those filters out but the charcoal filters are not worth that much. The best thing is to just get into a routine of knowing that you are going to have to do it every one to two months. If you see a difference within those timeframes like not absorbing correctly change them before. Figure out an efficient schedule and stick to a schedule instead of getting behind in the product starting to cause trouble.

Terry Nelson:

I tell guys frequently to watch the color in the sight glass, it will tell you the hydrocarbons content and usually, you have great knowledge of it. If you do not change them, they will become saturated. It is kind of like an “aquarium”. You have a charcoal filter in your “aquarium” that absorbs ammonia from the fish waste, when the filter gets saturated, your water starts changing colors and you get algae growing in your tank, which means change the filter and your water will clean right up. The same thing happens in a dehy when you change a charcoal filter you will notice your glycol and your sight glass cleans up a little bit. I am old if we had to do this, which we did. We had to dunk them in a 5-gallon bucket, and we would dunk the charcoal canisters. The charcoal when we had back in the day was not already activated. Nowadays most are activated charcoal. But the old way was not activated carbon, you had to activate it by submerging it in water. I do not know why but when you do it that way you get a lot of fines out of the bottom of the bucket. It would be just full of dust off the charcoal, and I am assuming it was a different kind of charcoal, a different kind of carbon because it was not activated. What was told to us was that it was not activated until you dumped it in water and then drained it out because we're putting water in the system. The system is supposed to be getting out water, but they just told us to watch it. When they came out with activated carbon you do not have to do that anymore, but that is why originally like the old units the old Smith systems had the reason they first put the particulate after the carbon was to catch all those fines that were in the charcoal canisters.

Chris Smithson:

They now make new charcoal canisters; it is just a solid block of carbon which is just a giant tube, and the glycol can go through it, but you are dealing with one giant hunk of carbon instead of the canister full of the fines and having future issues. We sell and install them in our small glycol units like the one pictured there. That picture has a little 125 reboiler. We use those in water housing instead of having a dedicated canister, because it is a larger canister, they must put on there we just put the no water housing. The solid carbon filter in there is nice because you do not have to deal with fines because it is one solid chunk, it has a finer filter. Also, a 10 micron or a 15 micron you will have to change them out a little more often because they will get plugged with particulates if you do not clean them enough or take them.

Emission Control pictures

Cameron Croft:

We are not going to have time for the fourth one, but the fourth one was emissions controls so what I am going to do is we are going to pass that on to next month. We are going to fully explain that, to wrap this up what I would like to talk through these examples, and then we will start wrapping up this workshop. Chris, can you explain some of these pictures?

Chris Smithson:

So as you can see the scaling on the fire tubes that were pulled out has giant flakes that have come out of this fire too, this is not as bad as it could be but there was a lot of stuff that baked onto this fire tube. That was either of them running the temperatures too hot and cooking the glycol onto it or impurities in the glycol just cooking onto the fire tube. It reduces your burner efficiency on it and the other pictures are on the fire tube. This is what Terry talks about when he says they come out and they clean you’re your fire tube. I do not know how long this one was in service for but, there is a tiny hole through what is an inch and half of the pipe and is now completely clogged off with soot because the burner was not optimized for its burning. It is nearly completely clogged off, but the fire is nearly ineffectual. It is clogged up with dirt and grime. I am sure Terry has seen examples of burners that look even worse than this.

Terry Nelson:

The whole reason for doing the burner checks as part of the winterization is just to get prepared. Winterization is bad and can cause a lot of damage. You must know it to be water or hydrocarbons, it is liquids, and that orifice gets plugged. Now you are restricting your burner I tell guys when you have a burner that does not seem to burn very well, take your adjustment needle for your fuel gas and run it all the way until it is shot so it stops them back out. Sometimes you can break that little plug off in that orifice and it will start burning better.

Chris Smithson:

The picture on the right might be Terry’s. That is some bad scale build-up. The picture on the left is caused by a fire. They had to carry out the still column and yet you cannot see the pipe anymore, but there was a pipe attached to the still column that angled over and the hot glycol is just a hot glycol. Most likely it had a bunch of hydrocarbons and it boiled over which then caught fire enough to melt the aluminum off the reboiler.

Terry Nelson:

People ignore the maintenance of the dehy’s and that becomes an issue. When having lube oils and other contaminants and just ignoring it over time and allowing it to overheat you will start seeing flaking. What happens is people do not realize that when you get a coating on your fire tube like this, you are affecting the thermal properties and the heat cannot transfer through that pipe anymore. Inside the fire tube, it will become overheated, and you are creating hot spots on the fire tube, and when that dirty glycol comes in the steel column, and it pours on top of your fire tube that is hot spot’s attracting those minerals. It becomes a domino effect and soon the fire tube will be covered in inches of soot. Over time the fire tube just collapses upon itself, and you have a fire-tube failure.

Jesse Olivares:

I think the failure would be that you will start having holes or buckling and then you have fires happening.

Conclusion of roundtable

Cameron Croft:

The biggest thing throughout this webinar was the proper maintenance and emission control. I was really wanting to touch base on this, but we will expand this out for the next one, especially with a new possible administration coming in. If we join the Paris Accord, there are going to be a lot more emission control issues. We want to talk about upgrading things that were seen in the past, but we are going to pass that on the next webinar. On the recap, this one was proper maintenance filtration looking out for liquid hydrocarbons, taking samples and identifying all the perimeters that Terry had in here. If you are interested in being a web and R speaker or know someone that would be a good fit, please reach out to [email protected] Please give us feedback, you all are the only reason we are doing this. We have two CEO's, director of engineering and a manager that runs a whole company right now on this. We are trying to share the information correctly; we want to make sure this information is coming across properly. Please give us feedback on what you would like to spend more time on, do you like what you're seeing? Would you want more visuals in images? Let us know and you will get a free hat or shirt. If you have anything after this and would like a follow up call with our team, we have done it in the past where we brought in several engineers and went on a zoom call in focus on our clients' issues or what the big initiatives that they're trying to do. Please let us know and we will make sure we get Terry, Jesse, Chris and myself on the phone call, please reach out to me if you have any questions on that. We're going to wrap this webinar up, I appreciate y'all spending the time and coming on and talking with us.

Croft Productions Systems
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