WEBVTT 1 00:00:02.470 --> 00:00:03.200 Maria Cristina: Yeah. 2 00:00:03.530 --> 00:00:06.219 Sukanya Sinha: I'm assuming, you know the jingle by now, so. 3 00:00:07.658 --> 00:00:10.200 Maria Cristina: So just a moment, okay. 4 00:00:13.460 --> 00:00:15.010 Maria Cristina: can you see my screen? 5 00:00:17.570 --> 00:00:21.350 Sukanya Sinha: Something's coming up. Yes, we see your full screen. 6 00:00:21.830 --> 00:00:27.099 Maria Cristina: Okay, can you hear me? Okay, perfect. Okay. So good morning, everybody. 7 00:00:27.330 --> 00:00:32.589 Maria Cristina: I'm Marie Cristina, Rena. I'm a researcher in the Petfs guest team group 8 00:00:32.740 --> 00:00:43.519 Maria Cristina: at Cerna, and with this presentation I'll show you the status of recuperation system for free net gases installed at the Cerna Lac experiments. 9 00:00:43.790 --> 00:01:03.110 Maria Cristina: So, as all of you already knows, gases detector installed in all the lac experiments, and also in many not lac facilities, and depending on the proposal and the geometry of these detectors different gas mixture are used. But the problem is that some of these gas mixture is made of greenhouse gases. 10 00:01:03.480 --> 00:01:20.679 Maria Cristina: So why not simply replacing this gas because the detector were designed more than 20 years ago when the effect of these gases was announced. So now there are a lot of R&D activities ongoing to replace this gas. But it is a bit challenging. 11 00:01:21.170 --> 00:01:32.690 Maria Cristina: So in this table you can see, there are summarized the many of the greenhouse gases used at Cern, and the proposed of these gases so that can be 12 00:01:32.960 --> 00:02:00.059 Maria Cristina: can be divided between detector cooling and particle detection as concerned the particle detection. The global warming potential go from 1,400 for their 1, 3, 4, 8 up to 22,800 for the Sf, 6. So you understand why it is so important to develop some strategies for reducing this emission. 13 00:02:00.190 --> 00:02:27.650 Maria Cristina: Fluorinated compounds represent the 78% of the total organization emissions, as shown in the last Cern environmental report, and the goal is to reduce by 28% this emissions by the hand of the country. The other problem related to the use of these gases is the European legislation of 2014, which started in 2014, according to which the use of these gases must be 0 by the hand of 2050. 14 00:02:28.134 --> 00:02:37.340 Maria Cristina: To reach these this goal there are different approaches, such as promoting the use of more eco-friendly alternatives 15 00:02:37.400 --> 00:02:57.999 Maria Cristina: and to reduce the availability of the gases when these alternatives are available and controlling and preventing dimission, especially in industries or laboratories where these gases are used. Obviously these strategies are causing gas shortages and increase of prices. So it represents a problem also for Cerna. 16 00:02:58.330 --> 00:03:01.950 Maria Cristina: For the moment. At Cern there are different strategies 17 00:03:02.070 --> 00:03:11.359 Maria Cristina: going, such as the optimization of the gas system technologies on our side with the gas recirculation and improvement of the gas of these gas 18 00:03:11.480 --> 00:03:29.920 Maria Cristina: recirculation system, the use of gas recuperation system. That is the focus of this presentation, then research for alternative gases, such as tetrafortane, sf, 6 or cf. 4. While the disposal, and abutment is not used for the moment. At Serna. 19 00:03:30.660 --> 00:03:43.829 Maria Cristina: As I told you, our gas system already work in recirculation mode. That means that part, or all the gas is continuously recirculated inside our inside our gas loop. 20 00:03:43.960 --> 00:03:56.479 Maria Cristina: however, some detectors that are permeable to hair cannot work with 100% of recirculated flow because of the nitrogen accumulation inside the gas mixture. So 21 00:03:56.650 --> 00:04:22.009 Maria Cristina: most of our detectors 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 usually the fluorinated compounds is separated from the other components, is purified, stored, and then can be reused or injected into the detector. 22 00:04:22.300 --> 00:04:42.550 Maria Cristina: The separation technique used in our recovery system, our 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, thermal pressure, swing, absorption or distillation. 23 00:04:42.740 --> 00:05:01.860 Maria Cristina: and we can separate the different separation technique according to the to the recuperation plant. For example, the Cf 4 is recovered mainly through membrane separation, while tetrafortane, Sf, 6 or 24 00:05:01.890 --> 00:05:16.480 Maria Cristina: T. 4 f. 10 is separated through the distillation processes, while usually pressure and thermal swing absorption are coupled to the to this separation technique in order to further purify the final compound. 25 00:05:17.010 --> 00:05:26.339 Maria Cristina: So let's start with the recovery system for the Cf. 4 installed in the Cms. Experiment for the cataly strip chamber detectors. 26 00:05:26.380 --> 00:05:45.450 Maria Cristina: So as first, st it is the 1st plant for the Cf. 4 for warm assorption, and it is an industrial scale, no standard gas system, and the CFC gas mixture is made of Argon Co. 2 cf. 4 in a ratio that can be 40, 50, 10 or 40, 55, 5, according to the Lacey schedule. 27 00:05:45.450 --> 00:05:58.750 Maria Cristina: And the system is fully controlled by software. So what we do in our system is to take the gas from the Csc excess module and send to the to the 1st module, that is, the membrane, one in which the Co. 2 is reduced to few 28 00:05:58.790 --> 00:06:26.130 Maria Cristina: percentage. Then the gas is sent to the 1st molecular seam, the 4 a 1 that is needed to reduce the Co. 2 to few Ppm, so, while in the last module, the molecular, that is, zeolite is used to really purify the Cf. 4, which is trapped, absorbed on the material, while argon and nitrogen that represents our main contaminants are not 29 00:06:26.130 --> 00:06:44.259 Maria Cristina: so. Thanks to the precious wing assertion, we are able to exhaust the 1st part of the gas that is rich in argon and nitrogen, while in the second phase of the extraction we recover the C. 4 that is then sent to a storage battery used to store and inject the gas. 30 00:06:44.450 --> 00:07:10.499 Maria Cristina: Thanks to this recovery system, we did a lot of rend activities in the last 3 years, thanks to which we reached around 70% of recuperation efficiency in the last year. And we must consider that the 60% of the total cf, 4 injected for the Csc detectors in the 2024 was cf. 4 recovered. 31 00:07:10.520 --> 00:07:20.250 Maria Cristina: and 8,600 tons of pseudo equivalent and 47 K's with France were saved, only the last in 2024 only the last year. 32 00:07:20.450 --> 00:07:49.490 Maria Cristina: as concerned the second recovery system installed in Cms. For the tetherful retain for the resistive Ray Chambers detector. It is a recovery plant based on the distillation process. The Cms Rpc. Gas mixture is made of R. 1 3 4 8 sf. 6 isobutan in a ratio 95.2 0 point 3 4.5. And the main problem related to the separation of these compounds is that r, 1, 3, 4, a forms a minimum boiling point at 0 tropuid isobutan. 33 00:07:49.650 --> 00:08:10.810 Maria Cristina: That means that once the azeotrope is formed, the gas phase will have always the same composition of the azeotrope. But, thanks to the initial composition of the gas mixture, we are able to recover the pure liquid. R. 1, 3, 4, a. And exhaust just the gas phase reach in the azeotrope composition. 34 00:08:11.830 --> 00:08:31.429 Maria Cristina: 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 module used to extract the 1 34 a. And the storage tank in which we store, and we use to re-inject the gas into their PC. Detectors. 35 00:08:31.430 --> 00:08:54.459 Maria Cristina: And here more detailed view of the single module, we have an heat exchanger, so we liquefy the gas coming from their PC. Exhaust. It is sent to the 1st module, that is, the top buffer in which we have the liquid phase, while in the bottom buffer we have the gas phase. And basically, what happens in our system is what you see in the simulation. 36 00:08:54.780 --> 00:09:02.440 Maria Cristina: So we have an heat exchange, because liquid, then gas phase, and in this way the distillation takes takes place. 37 00:09:02.910 --> 00:09:23.850 Maria Cristina: So, thanks to more than 200 tests that we perform in the last 2 years, the 2024, we reached our operation efficiency higher than 80%. It is almost a theoretical limit for this separation technique, because you must consider that there is for a loss due to the formation of the aziotrope 38 00:09:24.494 --> 00:09:31.030 Maria Cristina: but the quality of our country recovered is very good with a 99.5% of purity. 39 00:09:31.440 --> 00:09:42.899 Maria Cristina: So thanks to this system, in 2024, the 40% of the total l. 1, 3, 4, a used in their PC detectors was recovered. L. 1, 3, 4, 8, 40 00:09:43.050 --> 00:09:53.319 Maria Cristina: and thanks to this system, we expect to recover more than 70,000 tons of Co. 2 equivalent and 100 K's with France per year. 41 00:09:54.200 --> 00:10:23.469 Maria Cristina: The last system that I show is the Lacey B. Rich, one C. 4 F. 10 recovery system. So the rich one is a Surrenkos detector. So it's a volume of 4 cubic meters which can be filled with C. 4 f. 10. That is very difficult to find now in Europe or Co 2, so c, 4, f, 10, when we have data taking or Co 2, when we are in long stop, or yet. So no data taking. During these 2 phases, we need to 42 00:10:23.470 --> 00:10:31.369 Maria Cristina: recover the C. 4 f. 10. Just at the beginning of 2025, we installed a new recovery system. 43 00:10:31.820 --> 00:10:45.529 Maria Cristina: and that is currently used just in these days for the recuperation of the C. 4 f. 10. The idea is to take the gas exhausted by from the from the detector. 44 00:10:45.530 --> 00:11:14.329 Maria Cristina: It is sent 1st to an equalizing tank, because in general all the separation processes are influenced by the initial composition of the gas mixture. 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 C. 4 F. 10, while Co. 2, and air, that are the main contaminant substance to the atmosphere. 45 00:11:14.830 --> 00:11:27.079 Maria Cristina: Thanks to the work done in the last 3 years. We saved more than 300 kilos of C. 4 f. 10. That means around 5 volumes, 5 detector volumes. 46 00:11:27.870 --> 00:11:50.340 Maria Cristina: So, in conclusion, fluorinated gases are responsible for more than 80% of greenhouse gases emission. But, thanks to our recovery system, these emissions, already reduced by 20%. For the moment, we have 4 operational recovery system, 2 installed in Cms and 2 in Lacb, and the studies for a new recovery system is currently ongoing. 47 00:11:50.740 --> 00:12:16.409 Maria Cristina: Obviously, the use of a recuperation system implies more control on gas quality. So we perform daily gas chromatograph analysis. And also we need the online monitoring system, such as single wire, proportional chambers and infrared devices. But last, but not least, the recovery system obviously allows and allowed to overcome critical situation when new or fresh gases is not available. 48 00:12:16.620 --> 00:12:22.340 Maria Cristina: And it happened, for example, in 2023, at the beginning of the round trip. 49 00:12:22.750 --> 00:12:26.080 Maria Cristina: So thanks for your kind attention. 50 00:12:27.940 --> 00:12:36.749 Sukanya Sinha: And you're perfectly on time. Thank you for this really nice talk, Maria. Do we have any questions for Maria? 51 00:12:42.914 --> 00:12:44.570 Sukanya Sinha: Yes, I see Yan. 52 00:12:45.970 --> 00:12:59.809 Yann Coadou: Yes, so thank you for this talk. So you are mentioning future projects. 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. 53 00:13:00.530 --> 00:13:29.119 Maria Cristina: So when I speak about future recovery system, I mean that we are currently studying the possibility. So to recover also this, there are some studies ongoing. We have also some collaboration ongoing, because I mean, as in as shown in the table before, it has a very, very high global warming is the highest. So 22,800. 54 00:13:29.440 --> 00:13:50.869 Maria Cristina: 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 sf, 6. Starting from this recovery system. So we take the exhaust of this recovery system and trying to concentrate the Sf. 6. But there are. 55 00:13:50.870 --> 00:13:59.880 Maria Cristina: I mean, we are at the very beginning. If we manage to do this, it would be ready, maybe for the next round. 56 00:13:59.880 --> 00:14:22.830 Maria Cristina: because obviously, we need a lot of R&D to understand the right procedure. Then, obviously, we have these these systems. So just in case for the future can be possible to optimize also for other experiment. For example, if other experiment user 1, 3, 4, a. And they want to you 57 00:14:22.830 --> 00:14:28.950 Maria Cristina: to recover. We can try to do another system also for the other experiments starting from what we have now. 58 00:14:30.410 --> 00:14:38.999 Maria Cristina: but what I mean for future is this f. 6 1. That is still an idea. I mean, we are just studying for the moment. 59 00:14:41.690 --> 00:14:42.300 Yann Coadou: Thank you. 60 00:14:43.090 --> 00:14:43.650 Maria Cristina: Thank you. 61 00:14:45.130 --> 00:14:49.270 Sukanya Sinha: Thank you. Do we have any other questions for Maria? 62 00:14:52.900 --> 00:14:53.920 Sukanya Sinha: Thing? It was.