WEBVTT 1 00:00:00.530 --> 00:00:07.530 I'll reset the timer and um I'm assuming you know the jingle by now. 2 00:00:07.530 --> 00:00:13.530 So just a moment. Okay. 3 00:00:13.530 --> 00:00:17.530 Can you see my screen? 4 00:00:17.530 --> 00:00:22.530 Something's coming up. Yes, we see your full screen. Yes. Yes. 5 00:00:22.530 --> 00:00:27.530 Okay. Can you hear me? Okay, perfect. Okay, so good morning, everybody. 6 00:00:27.530 --> 00:00:33.530 I'm Marie Cristina Rena. I'm a researcher in the PETFS gas team group. 7 00:00:33.530 --> 00:00:44.530 And with this presentation, I'll show you the status of recuperation system for free net gases installed at the Cernel AC experiments. 8 00:00:44.530 --> 00:00:53.530 So as all of you already know, gases detector installed in all the LAC experiments and also in many non-LAC facilities. 9 00:00:53.530 --> 00:01:03.530 And depending on the proposal and the geometry of these detectors, different gas mixture are used But the problem is that some of these guys mixtures made of greenhouse gases. 10 00:01:03.530 --> 00:01:21.530 So why not simply replacing this gas because the detector were designed more than 20 years ago when the effect of discusses was announced. So now there are a lot of R&D activities ongoing to replace this gas, but it is a bit challenging. 11 00:01:21.530 --> 00:01:29.530 So in this table, you can see there are summarized many of the greenhouse gases used at CERN. 12 00:01:29.530 --> 00:01:55.530 And the purpose of these gases so that can be can be divided between detector cooling and particle detection. As concerned the particle detection the global warming potential go from 1,400 for their 134A up to 22,800 For the F6, so you understand why it is so important to 13 00:01:55.530 --> 00:02:06.530 Developed some strategies for reducing this emission. Fluorinated compounds represent the 78% of the total organization emissions. 14 00:02:06.530 --> 00:02:15.530 As shown in the last several environmental report. And the goal is to reduce by 28% this emission by the hand of the rantry. 15 00:02:15.530 --> 00:02:27.530 The other problem related to the use of these gases is the European legislation of 2014 We started in 2014 occurred in two weeks the use of these gases must be zero by the end of 2050. 16 00:02:27.530 --> 00:02:43.530 To reach these… this goal, there are different approaches such as promoting the use of more eco-friendly alternatives And to reduce the availability of the gases when these ecofen alternatives are available. 17 00:02:43.530 --> 00:02:49.530 And controlling and preventing dementia, especially in industries or laboratories where these gases are used. 18 00:02:49.530 --> 00:03:02.530 Obviously, these strategies are causing gas shortages and increase of prices. So it represents a problem also for For the moment at CERN, there are different strategies. 19 00:03:02.530 --> 00:03:25.530 Ongoing, such as the optimization of the gas system technologies on our side with the gas recirculation and the improvement of these gas Recirculation system, the use of gas recuperation system that is the focus of this presentation Then I'll research for alternative gases such as tetraforutane, SF6 or cf4 20 00:03:25.530 --> 00:03:31.530 While the disposal and abutment is not used for the moment at CERN. 21 00:03:31.530 --> 00:03:44.530 They told you our gas system already work in recirculation mode. That means that part or all the gas is continuously recirculated inside our gas loop. 22 00:03:44.530 --> 00:03:51.530 However, some detectors that are permeable to hair cannot work with 100% of recirculated flow. 23 00:03:51.530 --> 00:04:12.530 Because of the nitrogen accumulation inside the gas mixture so most of our detectors who works with recirculation of 90%, that means that 10 of the gas mixture is continuously sent to the atmosphere. But in some cases, this 10% is sent to the recovery plants where the greenhouse gases that is 24 00:04:12.530 --> 00:04:22.530 Usually the fluorinated compounds is separated from the other components, is purified, stored, and then can be reused or injected into the detector. 25 00:04:22.530 --> 00:04:39.530 The separation technique used in our recovery system are physical separation technique Because we cannot risk to form some byproducts that can damage the surface of the detectors. So we use mainly membrane separation processes. 26 00:04:39.530 --> 00:05:09.530 Thermal pressures wing absorption or distillation. And we can separate the different separation technique according to the to the recuperation plant. For example, the CF4 is recovered mainly through membrane separation while tetrafluridane sf6 or Tifuraftan is separated through the simulation processes, while usually pressure and thermos ring absorption 27 00:05:09.530 --> 00:05:17.530 Are coupled to this separation technique in order to further purify the final compound. 28 00:05:17.530 --> 00:05:26.530 So let's start with the recovery system for the CF4 installed in the CMS experiment for the CATO strip tonverse detectors. 29 00:05:26.530 --> 00:05:45.530 So as first it is the first plant for the worm assertion and it is a industrial scale, no standard gas system And the CST gas mixture is made of argon CO2CF4 in a ratio that can be 40, 50, 10 or 40-55 according to the LACC schedule. 30 00:05:45.530 --> 00:05:59.530 And the system is fully controlled by software. So what we do in our system is to take the gas from the CSC exhaust module and send to the first module that is the membrane one in which the CO2 is reduced to few 31 00:05:59.530 --> 00:06:26.530 Percentage then the gas is sent to the first molecular sieve, the 4a1 that is needed to reduce the CO2 to few ppm. So while in the last module the molecular shift 13x that is zeolite is used to really purify the CF4 which is trapped adsorbed on the material while argon and nitrogen that represents our main contaminants are not. 32 00:06:26.530 --> 00:06:44.530 So thanks to the precious wing assertion, we are able to exhaust the first part of the gas that is rich in argon and nitrogen, while in the second phase of the extraction we recover the CF4 that is then sent to a storage battery used to store and reinject the gas. 33 00:06:44.530 --> 00:06:59.530 Thanks to this recovery system, the fish, we passed from we did a lot of R&D activities in the last three years Thanks to each, we reached around 70% of recuperation efficiency in the last year. 34 00:06:59.530 --> 00:07:10.530 And we must consider that the 60% of the total CF4 injected for the CSC detectors in 2024 was CFO recovered. 35 00:07:10.530 --> 00:07:20.530 And 8,600 tons of pseudoevalent in 47Ks with France were saved only the last in 2024, only the last year. 36 00:07:20.530 --> 00:07:29.530 I was concerned the second recovery system installed in CMS for the Tetra for retain for the SSD free chambers detector. 37 00:07:29.530 --> 00:07:42.530 It is a recovery plant based on the distillation process. The CMS or PC gas mixture is made of R134A, seps6 isobutin in addition 95.20.3, 4.5. 38 00:07:42.530 --> 00:07:50.530 And the main problem related to the separation of these compounds is that R134A forms a minimum boiling point at zero point isobut. 39 00:07:50.530 --> 00:07:59.530 That means the ones that the entropy is formed the gas phase will have always the same composition of the axiotrope. 40 00:07:59.530 --> 00:08:12.530 But thanks to the initial composition of the gas mixture, we are able to recover the pure liquid R134A and exhaust just the gas phaser reached the end of the xyotrop composition. 41 00:08:12.530 --> 00:08:24.530 And this happened this take place in our recovery system. This is the PN ID of our system. It is made of the distillation units, the compressor modules to extract their 134A and the storage tank. 42 00:08:24.530 --> 00:08:31.530 In which we store and we use to reinject the gas into their PC detectors. 43 00:08:31.530 --> 00:08:49.530 And here, more detailed view of the single model. We have a neat exchanger, so we liquefy the gas coming from their pc exhaust it is sent to the first module that is the top buffer in which we have the liquid phase, while in the bottom buffer we have the gas phase 44 00:08:49.530 --> 00:08:55.530 And basically what happens in our system is what you see in the simulation. 45 00:08:55.530 --> 00:09:03.530 So we have an exchange because liquid then gas phase And in this way, the distillation takes place. 46 00:09:03.530 --> 00:09:24.530 So thanks to more than 200 tests that we performed in the last two years, the 2024 we reached a regression efficiency higher than 80%. That is almost theoretical limit For this separation technique because you must consider that there is a R13 loss due to the formation of the at the auto 47 00:09:24.530 --> 00:09:31.530 But the quality of a 12-free recovery record is very good with a 99.5% of purity. 48 00:09:31.530 --> 00:09:43.530 So thanks to this system in 2024, the 45% of the total R134A used in the RPC detectors was recovered at 1.34A. 49 00:09:43.530 --> 00:09:54.530 And thanks to this system, we expect to recover more than 70,000 tons of CO2 equivalent and 100Ks with france Period. 50 00:09:54.530 --> 00:09:59.530 The last system that I show you is the LACBH1C4FTA recovery system. 51 00:09:59.530 --> 00:10:21.530 So that each one is a length of detector. So it's a volume of four cubic meters, which can be filled with C4F10 that is very difficult to find now in Europe or CO2, so C4F10 when we have data taking or co2 when we are in long stop or yet so no data thinking 52 00:10:21.530 --> 00:10:38.530 During these two phases, we need to recover the C4F10. Just at the beginning of 2025, we installed a new recovery system And that is currently used just in these days for the reparation of the C4F10. 53 00:10:38.530 --> 00:10:55.530 The idea is to take the gas exhausted from the detector It is sent first to an equalizing tank because in general all the separation processes are influenced by the initial composition of the gas mixture. 54 00:10:55.530 --> 00:11:15.530 So once we have a constant composition of the gas, we send it to a recuperation system based also in this case on a distillation process. And then we are able to recover purely with the C4F10 While CO2 and they are that are the main contaminant substance to the atmosphere. 55 00:11:15.530 --> 00:11:38.530 Thanks to the work done in the last three years, we saved more than 300 kilos of C4F10. That means around five volumes, five detector volumes So in conclusion, fluorinated gases are responsible for more than 80% of certain greenhouse gases emission, but thanks to our recovery system, these emissions are already reduced 56 00:11:38.530 --> 00:11:46.530 By 20%. For the moment, we have four operational recovery system, two installed in CMS and two in LACB. 57 00:11:46.530 --> 00:11:51.530 And the studies for a new recovery system is currently ongoing. 58 00:11:51.530 --> 00:12:05.530 Obviously, the user of recuperation system implies more control on gas quality, so we perform daily gas chromatograph analysis and also we need the online monitoring systems such as single wire proportional chambers and infrared devices. 59 00:12:05.530 --> 00:12:23.530 But last but not least, the recovery system obviously allows and allowed to overcome critical situation when new or fresh gases is not available And it happened, for example, in 2023 at the beginning of the round trip. 60 00:12:23.530 --> 00:12:28.530 So thanks for your kind attention. Commission. 61 00:12:28.530 --> 00:12:34.530 And you're perfectly on time. Thank you for this really nice talk, Maria. 62 00:12:34.530 --> 00:12:35.530 Thank you. 63 00:12:35.530 --> 00:12:42.530 Do we have any questions for Maria? 64 00:12:42.530 --> 00:12:46.530 Yes, I see Jan. 65 00:12:46.530 --> 00:12:51.530 Yes, sir. Thank you for this talk. You are mentioning future projects. 66 00:12:51.530 --> 00:12:52.530 Yes. 67 00:12:52.530 --> 00:13:00.530 Are they already well identified or it's just that you hope that for instance other experiments are going to say yeah okay we have to do something here 68 00:13:00.530 --> 00:13:17.530 So… When I speak about future recovery system, I mean that we are currently studying the possibilities so to recover also the CF6. There are some studies ongoing. We have also some collaboration ongoing. 69 00:13:17.530 --> 00:13:29.530 Because, I mean, as shown in the table before, it has a very, very high global warming. It's the highest So 22,800. 70 00:13:29.530 --> 00:13:51.530 So this means that even a very small quantity it has a very high impact on the environment. So the idea is to trying to recover these cf6 starting from this recovery system. So we take the exhaust of this recovery system and trying to concentrate SF6 but there are 71 00:13:51.530 --> 00:14:21.530 I mean, we are at the very beginning if we manage to do this, it would be really maybe for the next round because obviously we need a lot of R&D to understand the right procedure then obviously we have these systems so just in case uh for the future can be possible to optimize also for other experiment for example if other experiment user 134A and they want to 72 00:14:23.530 --> 00:14:42.530 To recover we can try to do another system also for the other experiments starting from what we have now But what I mean for future is for future the sf61 that is still an idea i mean we are just studying for the moment. 73 00:14:42.530 --> 00:14:43.530 Thank you. 74 00:14:43.530 --> 00:14:45.530 Thank you. 75 00:14:45.530 --> 00:14:53.970 Thank you. Do we have… Any other questions for Maria?