 So we had started on air pollution some time ago Okay, so we did this we looked at what is air pollution? What is clean air? what year Different life cycles assessment, etc. etc. We did all of that Then we went into looking at different scales. What are the concerns ambient indoor dispersion mixing all of that stuff Then we said the learning objectives and we said There were two learning objectives for the first module then these are the standards available and then we gave I didn't say this last time, but one of the assignments. I usually give is just have them put all the standards whether it's CPCB US EPA Europe World Health Organization, California has its own standards put all of this for the exercises that they need to Be able to put it on an a4 side sheet Okay, so there'll be the pollutants and there'll be different columns each one of them would be a different norm We is followed by a different country or a different organization. So just doing that one exercise completes that whole matter of standards Okay, and I'm saying this again I'm sharing some of the experiments that we've been doing which have worked So I'm just sharing these if you like the idea use it if you don't like it use something else Okay, all right So then we did this exercise in class where we said, you know, how much sulfur dioxide so that gives them a direct One-on-one. I think half a sheet of paper had also given to you last time for let people estimate That what should be the size of the room for me to be able to burn two milligrams of sulfur such that you know I'm still in a safe space safe air Safe air quality levels. Okay, so we did all of that We did the chemistry was straightforward. What's the volume? Of course can't forget the double Dhama cars, right? And we said, you know, and you should actually give a chocolate. I mean people who did well You should give them a chocolate. All right. Now, here's the difficulty I told you last time also that there was difficulty Difficulty is that the data varies all the way from estimate of about 10 to about, I don't know how many zeros over here But I think about eight orders of magnitude Okay, so just now to deal with the statistics Just add them all up and divide them by the number of students you're gonna get pretty much the average somewhere here So whoever is higher will actually win cheating Okay, now this is not just a fun exercise in classes actually that's what the real situation is in life When you get a lot of data coming from many sources to be able to put them together But this is just an introduction to the students to say look Data that you and I are normally used to in terms of a physics experiment are not what's going to happen when you're dealing with environment So, you know, we did that We did this then, you know Somebody had asked are we at some point in time going to cover global warming So I'd never in my class. I don't deal with global warming. All I do is ask them to see movies Okay, so they see this movie and I give them two or three days By the way against not see study the movie. All right, so they do that and then they come back After some two three days, I'll give them the next part, which I'll come to a little later so the learning objective of The estimate pollutant etc etc that's handled and then we say okay we're going to look at able to just the influence of meteorology on the Physics and the dispersion pollutants in the atmosphere. So we deal with that part How do sources affect ambient air quality? That's the question Okay, and we said, you know different kinds of sources. You have a point source. You have a line source You have area lines etc the quantified based on emission factor Which is so for a car moving every kilometer how much carbon monoxide is produced? So if I know the number of cars, I know the number of kilometers traveled I know the number of amount of carbon monoxide in that area, okay? Similarly, you know you for other activities and then once it has left the source Once it has left the source We're pretty much going to depend on dispersion of that and then we use modeling to be able to estimate How bad it really is or what are the main culprits? Okay, so again we did this last time So we dealt with this we said, you know this this very hot spot over here This hot spot over here this good strong red which you cannot go do your prana. I am on by the time it comes down over here And it gets mixed with a larger volume it becomes pink So it is diluted and by the time it reaches ground level you would actually be able to breathe that without any health effects Okay, when rose we also said we introduced I introduced to a special breed of people called Meteorologists and said okay This is the most romantic rose that they could come up with at the same time I totally appreciate the kind of richness of this graphic which takes into account the wind speed Wind direction as well as the frequency or the percentage of time that in a year or in a month or in its varies Okay, it can be on a daily basis. It could be an annual basis if you take an annual basis It doesn't change very much from year to year But at the same time it doesn't have the resolution of a day which you can use which you can do by using Model you know data for at a daily resolution also. Okay vertical mixing. We said the false ceiling In this room over here, there's paka here paka here paka here But in the atmosphere where the ceiling is how high is the ceiling is there a ceiling? That's going to decide how much volume is available for me for the mixing to take place and therefore the dilution of a particular pollutant Okay, so we dealt with that in terms of the overall lapse rate And we said there is the adiabatic lapse rate and there's the environmental lapse rate based on that We did some fun stuff in the class. You're welcome to do it. I will animate it a little more Didn't have the time here, so I'll animate it a little more so that it's clearer when we do a final presentation in June Okay, so we did all of that a little bit of fun over here, etc. Etc. We've gone through all of this We did a class exercise We did this and then we just review. Okay, these are the things that we've done So we also said as you were leaving last time I know we said why are we doing all of this we're doing it because if you need to set up a new industry It implies adding a new source of pollutants This source is permitted by the way. Okay. It's not a bad thing. They're actually permitted by law. They're permitted So if this source is permitted to emit after it has applied the best available control technology on their processes After leaving the chimney the concentrations on ground is determined by the meteorology We don't have much of a say in the matter. You and I are pretty much left to the hands of meteorology Okay So if you wanted to know where to put the new industry if you wanted to know the pollution levels under the worst-case scenario of Stable conditions especially during winter time then what under low wind conditions What is the worst possible scenario and you need to be as designers as people who are designing the air quality You're designing the location You need to be able to deal with not just what is being said but of a factor of sometimes 5 sometimes 10 to be able To make sure that you know you are under in the safe limit Okay, so if you want to know what height does the chimney need to be you need to do this You need to have this understanding so students would be interested. Why are we doing all of this? Ultimately I said at one point in time you are you are you are the collector of your town So you better know this, you know what chimney how I should the chimney go Okay, so I think we need to oh you really want to do this Okay, the skit that happened yesterday and day before yesterday is complete now like the cricket match All right, there's a certain lifetime to it You want to just honor for the lifetime it has it has its impact and then you need to let go so no I request you to take that back He's not that who he is for me is a partner in the fulfillment of this course right now Okay, okay good. All right good All right, so what if why so Gaussian blue model is therefore used to estimate the ground level concentration of pollutants coming from from a chimney Okay inputs to GPM height GPM is the Gaussian blue model height of the chimney windows data atmospheric stability of the region These are not so easy to get they're difficult to get but once you get them. That's what becomes the input We talked about Mumbai a little bit. What is the predominant wind direction? That's a predominant wind direction That's where the refineries are that's where raster chemicals and fertilizer etc etc So most of the time people in Mumbai the population of Mumbai is not getting affected by the pollutants because most of them are Taken away never mind what happens to people in Navi Mumbai Okay, however and by the way when these plants were set up Navi Mumbai was non-existent almost it wasn't there Okay, so it's unfair to say now that you know Hey, you guys but the fact of the matter is that if Navi Mumbai is experiencing some pollution problems It's really coming from the Mumbai side Okay, however the concentrations etc over here are diluted enough that it doesn't affect too much at the same time people are reconsidering the heights of the chimneys They're actually reconsidering the best available cultural technology 30 years ago versus now so that if they were emitting at a level of 100 Can they emit at a level of 10 now? Okay? That's a responsible thing to do and people actually engage in this conversations. All right So then one of the exercises I gave around this is find the wind rows for Mumbai or your home city You may be able to find it. You may not be able to find it That's fine But just to go on Google and say win rose and type your city name It may not show up. Okay, but you will get some win roses. You may want to find for the closest city That's available. So some some interest some curiosity can be you know brought about for the students Another one is does your city does it have a meteorological station? Let them find out Let them actually get into a relationship with what does the IMD do? It's important see I think one of the important things we need to do for our students is to connect them with Different groups of people different government organizations that are already in place to take care of certain things Okay, so that's a part of the exercise. You got to start get them start thinking You just got to get this out. You can't give them get them out of the door get them out of the textbook Textbook they could put under the pillow and by osmosis. They will get it, okay? But they're not going to be able to get what's not in the book which only you and I can provide So this is what we did last time, right? Okay, so can you give a big clap for the last time's work? All right, two or four. We got four modules. Okay, so this is the second of the two modules, okay? So this is part a of the homework that was given to them To study the movie and inconvenient truth, right? Okay, so this is now part B Please study the film this one and then what I do is I give them a day and date But that is three days after part a is complete Okay, there's a certain gestation period here. They actually have to They you know the way they go is three days. Wow. I know now what global warming is, you know I'll go to the vice president of us has actually been able to tell me this etc. Etc. They're in that little world of theirs and you give them three days and you know They see this other movie and it pulls the rug under their feet Suddenly the ground that they were standing on disappears and they have no idea what's going on anymore And then they come and ask sir. What is the right answer? I said, I don't know That's why I asked you to study the two films So I'm not committed to giving them the right answer because I don't know if there is any Okay, that also gets them out into see one of the things I've been telling people by the way when this assignment is submitted I don't know if I said this to you already before but even if I have sometimes people copy, okay? Sometimes people copy so when people copy and come I usually tell them look if this question actually came up in a group Discussion during an interview. Are you ready for it? No, I'm not good then go redo it Because this is the only time you'll get to actually give thought to it and engage in this question No time else if you can mechanical engineer or if you're civil engineer, there may not be another opportunity for you to engage in this question So it's time to do it now. You need another day or two days. No, sir. I'll give it to you by lunchtime I said you cannot do it by lunchtime So give it to me in two days and then they make a promise and do it, right? So the idea always is to actually have them engage Not necessarily getting the right answer But for them to start thinking and actually expand as a human being because they've just been obedient students till now Hello Obedient students till now, right? You do you want to have them expand into the adulthood You want to have them expand them into questions that they were dealing with which till now only their parents were dealing with Alright, and then I announce three days after part B is done I make the announcement of the assignment and the assignment is this I actually give these details and I'll just share that with you now Okay, so basically I give them a critique What they have to do is write a minimum thousand word critique on what is their stand in the domain of global warming Okay, so they have to study the two films and then come up with a critique. All right, okay Next part so what did we do till now the metriology dispersion those kinds of things right now? We've also touched upon global warming Right, they will have studied on their own. They'll have more questions now than we have answers for and that's fine We leave it at that this part now. You'll be able to qualify a pollutants So we just say pollution pollution, but we need to know what they are what are those pollutants? And we say there are two kinds of pollutants in the air one is gaseous and the other is Particulate okay, so there are different ways of measuring it So for example, are you looking at so when we did that exercise on sulfur dioxide? We looked at concentration and we said micrograms to meter cube a lot of times it is PPM which is volume by volume many ways of doing dealing with it and you know They could also be when it comes to particulate matter. It could be number of particles rather than mass of particles Oh, by the way, this one is one of my favorite. How many of you seen that advertisement of Fair and lovely in which they have a strip of different skin colors Right, and then what you're supposed to do is take that thing and match it against your face And then for two week Oh buh buh buh buh buh buh buh buh you do that for two weeks and then two weeks later you come and look to see aha I've shifted to you know I'm saying So that seems to be like a new thing in all no no no people in the air quality have been using it for the longest time They used to have a grayscale so they would take this grayscale and put it against the sky against the smoke coming out and Based on which level of grade they'd be able to say how polluted it was it's been a it's been you know very fairly well used well documented all right Again from the perspective of exposure You need to deal with hours to days So for example for three hour exposure for sulfur dioxide There's one standard for eight hours is a different standard for 24 hours is a different standard Okay, so the amount of time for which you'll get exposed is a part of the standard These are the criteria pollutants. What is criteria pollutants criteria pollutants are? Pollutants that are used to indicate the health of air So if I go to the hospital and the doctor looks at my blood My heart heart rate right my body temperature That usually is a good indication of what's going on mostly okay However, it's my age now You know the beginning to actually look at blood pressure and other things also sometimes They even send me for routine blood tests etc etc But otherwise if you just look at normal human health if you're you know if your head is cool and you're you know Pulse rate is okay. Typically, you know you're doing fine So in some sense if you didn't want like a very detailed chemistry of what is going on There are just few criteria pollutants These are the pollutants that are used as criteria to estimate the health of air Okay, and all of these in some way or form are associated associated with human activity Okay, all of them are associated with human activity and we get into some of the details ozone by the way These are primary and this is secondary secondary means it is not directly emitted from somewhere Oxides of sulfur are coming from any Any combustion source which has which is using fuel which has sulfur in it oxides of nitrogen anytime you're using air as Anytime you're using air oxygen is being used, but nitrogen is also, you know, high temperatures will get oxidized, etc PM 10 is what we're going to talk about particulate lead lead used to be used in Once upon a time in petrol For what anti-knocking? Tetraethyl lead. Yeah, so tetraethyl lead. So what happened suddenly? They're not using lead anymore How come the engines have started behaving themselves and they don't knock anymore? Okay, so they've changed the fuel They've changed the composition of the fuel and there are issues around that but right now it's not being regulated However, the particular pollutant that was coming in the form of lead is now, you know reduced That's it. So that's that's all I'm going to say and this is again coming from day-to-day human activities Okay, whereas industrial emissions are different. What is coming from a chimney? This is not what I'm talking about right now. Okay, when you're talking about standards We're talking about ambient air quality standards, which are for these Industrial sand emission standards are there, but then it's just specific to a particular industry Specific to a particular size of the industry and all that kind of stuff. All right, so we need not get into that right now Okay, so we'll focus on PM 10, which is particulate matter less than 10 micrometers in size Particulate matter which is less than 10 micrometer in size Okay, and it's actually has the units of concentration which is mass per unit volume micrograms for meter cube Let's talk about that. Okay, so How would you measure particulate pollutants you basically take a polluted space over here take a tube Put a filter over here, which has been pre-wade You have a flow meter So you know you're taking a 10 liter per minute or 20 liter per minute You have a vacuum pump and then what you do is you do some measurements So the filter paper that was weighed before and the filter paper that was weighed after So you basically have now the amount of particulate matter that got collected on that filter paper in How much time well q was the flow rate you had a stopwatch also So you found the time for which that flow rate was maintained. So it is So delta m by qt is the concentration of particulate matter in this space. Yes straight forward Not complicated at all. Right. Okay Now particulate matter if you were to do that if you were to do this in a desert village in Say Rajasthan somewhere Okay, versus if you did it in a busy urban junction, let's say outside main gate at IIT. Okay, would they be similar? No, no, in fact, there's a likelihood that the particulate matter in the desert is much higher Right So how do we deal with this because all we did over here was take the total amount of particulate matter We didn't make any distinctions between size or anything else Okay, so we need to now qualify this because you can't call you can't use this standard to go to Rajasthan and say hey, you guys are very polluted that's that's what they won't apply. Okay, so the appreciation of size begins to now come in and Not all particles are created equal human beings are human beings are Not all particles Okay particles are not created equal. Let's talk a little bit about that So this is when I do a little bit of board work in the class Okay, the board work I do in the class and I say how many of you know what is the size of an ant? Size of an ant and moongi moongi Chinti Chinti everybody know Chinti. Yeah, okay So I actually go on the board and make a dot and I ask somebody at the back of the seat You can see this. This is yeah, I said then it's not an ant Because you can't see an ant from that far right, okay So ant has a certain size and people don't go around measuring ants. Do you I? Don't think even as a kid. I did that take a scale and say let me measure what this and size I don't do that But typically what is the size of an ant somebody please? One mm. Okay. Okay. All right one mm two mm somewhere there Yeah, not the big black ones and the small red ones the small ones the one thing bite really bite Black ones are going like majestically. They're much bigger. I'm not talking about those. Okay, everybody in the world of ants now ants you love ants Love and so this hand right hand you love ants. Okay, very good. Now ants are gas molecules in the air Ants are gas molecules in the air. Let's just say let's just say ants are gas molecules in the air So, oh, what is that an ant? Did you see an ant? This year did you see that? Really really you saw an ant you pretty good eyes. Yeah, you can actually see ants over there Oh, there's another that there. Oh, there's another one. Yeah, right there anymore. Oh What is that Excellent well said well said because It's actually an elephant It's actually an elephant, but you can't see all of it on this scale You know, I can't put an ant and Elephant on the same scale on this. Sorry. I need a much bigger screen. I can't do it. So sorry That's all and this is the best I could draw What a lovely elephant, isn't it? Yeah, never mind the ants ants look like stars over here But you know you get the point, right? So the point is that I actually I'm dealing with Elephants that are suspended in an ocean of ants when I'm looking at particulate matter When I'm looking at particulate pollutants and in the class what I do is I take a duster two dusters I take and I say, okay, everybody ready. I put seeds against the light and I do put put put in this He all this dust going around Okay, that is all elephants Ants you can't see yeah, can you see the ants right now? You can't but ants are the ones which are causing the sky to be blue The molecules in the air are scattering light So therefore you see the blue sky. So you because it's you know 10 kilometers etc. So you can actually see it, but Everybody with me. Okay. Good. All right. So we got Elephants suspended in ants our perception our understanding has to come from that place Otherwise, we'll not be able to appreciate what it takes to deal with particulate matter gases We understand very well particulate matter only in the last 30 40 years. We've started to develop an understanding Okay, so okay, by the way sometimes even dinosaurs Okay, so if I take if I go to the ground outside and I pick up some mud from here and I throw it in the air What will happen? Some of the particles will settle out some of the larger particles will settle out some of them will Begin to float away diffuse out. Okay, so those are but they're still visible compared to the ants They're still visible right so these are the elephants and dinosaurs and dinosaurs went but quickly right? But they're still in the air. They're still out there, but they don't stay in the air long enough So therefore it's not too much of a concern from a perspective of air pollution if it goes into the air It settles out very quickly so you and I are not breathing it But there are particles which remain the elephants remain floating the ants keep them up Baby elephants. Okay, let's say baby elephants. All right, okay, okay So just to get scales and two millimeters spherical baby, baby you already knew it, huh? All right, so spherical baby elephant is about to spherical spherical watch what spherical, okay? So to so this is a three orders of magnitude, right? Similarly nitrogen molecule and respirable particle is also three orders of magnitude convinced or should I keep talking? About this I mean I keep talking but about this Okay, good. Let's move on All the well-established physics of ants ideal gases everybody know ideal gases Okay, all the principles all the physics of ants is not applicable to the elephants Okay, all the magic of nano heard of nano nano nano. Yeah, no everywhere all the magic of nano is in this new world of elephants Ability to understand this range of sizes has become possible due to develop of instrumentation in the last 30 40 years Therefore before that even the handbooks ended at two micrometers Below two micrometers. Oh particles didn't exist. They almost considered it gaseous And you know the places where it's making a difference is you know, that's all science and engineering powder production nano products atmosphere medical sciences Medical science is it people seen we'll come to that. Okay later. Okay. This is a slide. It's I want to acknowledge I got it from this company a sponics. I think it's a beautiful slide. It covers a lot of details In a way in which students can appreciate it. Okay, this is what is visible to the naked eye This is an optical microscope and then scanning micros etc. So different, you know levels of Resolution that you can get this over here is 10 micrometers 10 micrometers. This is 100 micrometers Okay, this is the visible band of light Visible band of light. Okay, and that's about human hair Human hair is about 100 micrometers. So which means if I put 10 hair one next to another They'll fill one millimeter space on a scale 10 what 10 hair put together next to each other will make one millimeter 100 micrometers is naked visible to the naked eye. You can see a hundred mile. You can see hair You can see people's hair, right? Okay, good red blood cells About 8 to 10. That's the range. You don't see them with naked eye You can only see them with a microscope very good Paint pigment why I talk about paint pigment is because there is also an interest in these particular matter from the perspective of quality of powders so paint pigment for example if you went in picked up a White paint from a company and you picked up a super white paint from the company The only difference is that the super white actually has paid attention to the size of the particles and Selected the size in such a way that it scatters maximum amount of light and Therefore you require lesser of it. So it is five times more expensive because it is ten times more effective Okay, so some people, you know students might be might suddenly get interested from the physics perspective or materials perspective And the physics is the same. It's not very different at all. Okay. All right now This is where we begin to deal with the health effects 10 micrometer anything which is greater than 10 micrometers will get stopped in your nose The design of an human normal human adult nose is such that 10 micrometers and above will get stopped in the nose Above 10 micrometers will get stopped in the nose human nose Human nose I then give an exercise on what would be respirable for an elephant That should be fun, right? I Haven't got an answer to that one yet, but anyway, we still got three months to go. We will find an answer to that one Okay. All right Anything less than 10 micrometers is respirable So therefore the definition of PM 10 PM 10 means Respirable particulate matter by human beings adults not children Okay, 10 micrometer for human beings, okay. Oh This is when I actually bring in a little bit of fun. You should see whether it's It's culture sensitive culturally sensitive So you just want to be careful about whether you want to use it or you don't want to use it I actually use this to say hey tobacco smoke to Mac to tobacco smoke. Hey tobacco smoke. Hey tobacco It's all respirable Thank God. Otherwise you'd have wasted your money Okay. All right, and then the next part of it is that this same The same physics is applicable to delivery of medication through the respiratory route the same principles By the way, you know you are delivering a drug using a cigarette, right? Now if that was done for medical purposes, it's a good thing How many of you seen sometimes, you know, you have colleagues or students who dealing with asthma They carry a little dispenser with them and they were like that, right? A large part of the problem of design of that is that the droplet size of the medication is not the right size For it to get all the way to your lungs it actually, you know, 90% 80% of it gets just stuck over here Okay, so the physics is the same. So if somebody's interested in developing, you know going into the research around how to deliver medication through the physics is the same I rest my case Go on. Okay. Good So, you know, those are some of the relative sizes very important figure Extremely extremely extremely important figure. In fact the entire Air quality for pollutants particular pollutants can be oriented around this one graph Okay, and what it is is this it's got three plots on it and it's got three axes on it. Okay, so the first plot First thing is that this is the size of the particle the diameter of the particle when I we say diameter We usually mean aerodynamic diameter because the physical diameter is very difficult if you take a particle from the atmosphere and put it under the Microscope, it's not spherical the moment you say diameter it assumes already in the saying of it that it is fair Okay, so we only talking about aerodynamic diameter, which is we can get into the details of that later So this is the aerodynamic diameter this over here This axis is some representation of the frequency or the number mass size distribution function Okay, so and this one here. I'll talk about a little later. So there are three plots here one the black one here Can you see this one the black one here this one? Right this one. This is the mass size distribution So based on mass This is the distribution you would get and there are three modes in it The first mode is the nuclei mode The second mode is the accumulation mode and third is the course mode course mode by the way all of these are respirable All of these are respirable, right? Okay, so this one over here. This is the course mode It usually will come from dust it'll come from a desert or it'll come from just entrainment of dust Which is coming from the ground some agricultural land or even road dust which is sitting over there So this is the course mode, which is the large particles By and large benign because they're large they're coming from geological sources So they don't have much of a toxic effect this part over here this part of the nuclei mode is the one which is emerging from chemical reactions Okay, it's emerging from chemical reactions somebody mentioned over here. It's a collection of ants very well said because At some point in time How many of you from from a cold city from a place like There are doing Darjeeling Missouri some place which gets cold in Delhi also it gets cold in winter time We used to do as kids now used to pretend Remember we should do that Basically pretending we are smoking actually we used to get smoke out of our mouth, right? so the The air in the mouth is what fully saturated at 37 degrees Celsius Outside temperature 4 degree 5 degrees the moment it comes out the temperature drops it gets saturated and suddenly you see a visible droplet In the mouth if you look other than Krishna you see the entire Brahman But otherwise, you know, you don't see anything other than my bad teeth, right? You don't see any vapor. You don't see the ants in there You don't see the ants the water vapor is in the form of ants in the mouth You don't see it okay, but the moment it comes out The temperature drops the saturation is exceeded and these water molecules actually become droplets Okay, that is a collection then of that elephant that is formed is truly a collection of those ants who had said that Somebody said yeah, so that's okay. So it's basically a collection of ants, but it is the birth of an elephant It wasn't there before It wasn't there before it came to be because of the saturation conditions Earlier than that in its previous avatar. It was just an ant Okay, we can get into the physics of it and all that stuff you won't get into that right now But then you know when you look at say Let's say a candle burning candle burning on top of it There's this black particles that are coming and those black particles are not in the wax, right? They're not in the wax the wax gets melted goes up the capillary Begins to get oxidized and it's not full combustion if it was full combustion then there wouldn't be the romantic light around it By the way by the end of this lecture usually people don't look at candles at romantically at all You know all they see is oh, where is the aerosol? I'm so bad. I'm telling you So you know you we used to do this as kids, right? We should take a piece of paper and put it just above the candle so we would get a black spot, right? Where is that coming from? Those are elephants by the way But they're not coming from that same pathway you do that and that actually no it is actually coming through chemical reaction So there are two pathways to these small particles one It could be nucleation which is the first one and second one is chemical reaction, right? Okay, good So this mode is coming from nucleation on the nucleation, which means You know chemical reactions or formation or birth of particles coming from vapor phase. This is coming from dust Right, and then you have somewhere in the middle the accumulation mode and that accumulation mode is actually a result of The particles are not big enough that they will deposit out The particles are not big enough that they will deposit out by sedimentation They're not small enough that they will diffuse out like gases So the removal efficiency of these particles from the atmosphere is lowest So if I take this slide and I invert it just flip it over Horizontally you get the accumulation mode So notice, okay, if I take this and I flip it vertically it actually will become this mode Okay, about the same size somewhere near one micrometer So these particles are not big enough to deposit out neither small enough to diffuse out So and you and I expose maximally to this because it remains in the air for the longest time Okay. All right. So talk to each other about the three modes. Go ahead talk to each other about the three modes. Please go ahead Okay All right, very good Now this was mass concentration. Okay mass concentration now when I look at the number concentration Number concentration is not the same as mass concentration. This blue plot over here. This blue plot over here represents the number So particles that are getting generated by chemical reactions or by nucleation are huge in numbers But they don't contribute much to mass Why they don't contribute much to mass is because one one micrometer particle is equal to how many point one micrometer particles One one micrometer particle in mass is equal to how many point one micrometer particles thousand Thousand because DP cube pi by six DP cube so their cubic relationship is there therefore while the numbers are huge One particle over here somewhere will contribute to about thousand times the particles over there. Okay, so that little game continues All right. So that's basically the other mode the other plot third plot, which is an important plot is this plot Okay, this plot over here and Again, it is saying that not everything that is Respired not everything that you breathe Actually stays in the lungs. Most of it is exhaled out Okay, so then what other particles what sizes should I be worried about? Okay? Let's take a look what sizes we should be worried about if you look at this over here this size Which is less than point one less than point one Less than point one. There's a good 70 to 80 percent chance that it will deposit in the alveolus Everybody know what alveolus is? Alveolus is that last little balloon in your lung and that's the only place I remember from my class 10th biology That's the only place where the color of the blood in the veins and arteries is different You remember Okay, the artery over there is carrying the blue blood The vein is carrying the red blood because it got oxygenated in the lung, correct Each of these alveolus have a rich capillaries around it which are doing that with the exchange is happening here If that got covered with particulate matter, I Have lesser surface available plus it can actually do toxic stuff. It can actually damage those linings Okay, so our concern therefore is particles which are less than point one micrometer have a good chance that there are other Parts of the respiratory tract where other things will deposit Okay, but in the alveoli you can expect most of the particles 70 to 80 percent of the particles which are going into your alveolus We'll actually deposit. Okay, which is a little alarming now Which is a little alarming because we just said that most of the chemical reactions that lead to particles are in this mode So anything which is smaller than this this part is benign Even if you breathe it in not a problem It's benign geological material, but this part over here is toxic stuff that is emerged from combustion Etc. Reactions etc. And therefore you have a concern. So we therefore now say oh, okay We're not just going to talk about total mass of particles We're going to actually have a size distribution or have a size specific Qualification for particulate pollutants enough. Okay, good. Okay, this one here Like we said, you know how in a place like Deradon you can pretend that happens same thing happens in coal combustion In coal combustion the coal itself will have several heavy metals When it goes through the hot flame zone hot zone these heavy metals evaporate When it reaches the cooler zones, they actually begin to either nucleate out or react or condense on smaller particles Thereby enriching these small particles with heavy metals Okay, so smaller particles by weight to weight. They have a lot more deposition lot more condensation of what of heavy heavy metals vapor, okay? We can get into details of this later. Okay Let's some measurements in Mumbai always good to see, you know It's okay to go to Google and find out all the stuff that's been going on in Pittsburgh in New York But always good to always find out what's going on in India What's going on in Mumbai? So there were two measurements that were made in some parts of Mumbai This is almost like now eight nine years ago and the The size distributions are pretty similar So in India, it's not very different from anywhere else in the world Most urban places would have size distribution that look like this In fact PM 2.5. I'll talk about that a little bit. So this is PM 10 everybody understand PM 10 now So the area under this curve Area under this curve is PM 10 the total mass concentration less than 10 micrometer in size However, we just said the listen not all particles are created equal Some of these particles are toxic and coming from chemical reactions and they usually tend to be less than 1 micrometer in size So should I be looking at within this PM 10? Should I be looking at a further qualification and that further qualification is called PM 2.5 PM 2.5 is what PM 2.5 is particles that are less than 2.5 micrometers PM 2.5 is always a subset of PM 10 PM 2.5 is always a subset of PM 10 Okay. Now if I were to take a ratio of PM 2.5 to PM 10 Everybody understand that anthropogenic and combustion are same Which is reflecting in PM 2.5 if I'm going to talk about the benign part then the PM 10 Accumulation mode or large part of the course mode would be contributing to PM 10 So I'm really comparing between the contribution which is coming from combustion sources and anthropogenic in PM 10 So PM 2.5 is considered to be the anthropogenic component of PM 10 okay, so If the ratio is small Which means PM 10 is much larger PM 2.5 is smaller. Then I don't have to worry. I don't have a health concern so in Rajasthan in A village in Rajasthan in a desert PM 10 will be high But PM 2.5 very low because there are no any chem in there's no industry Maybe no chemical reactions going unless you go into a chula and actually measure it No, but if you were just look at the ambient, there's no combustion. So the baby is coming from dust So PM 2.5 is not there so the ratio is small. So most of it therefore is benign however, if PM 2.5 is large Then I have a concern because then what I'm saying is that the large component of what I'm breathing is now Going to be toxic and you know, it's going to deposit in my lungs fair enough Okay, good now some results here for Mumbai. This is PM 10. This is PM 2.5 The ratio is the slope Correct ratio is the slope. So this is the ratio given over here in Develop countries it's as much as 0.7 0.8. So we initially felt very happy that ours was lower But the total amount that we have in the atmosphere in India is 5 to 10 times what they have Okay, so this this ratio doesn't make sense if you have and I'll come to that a little bit later So can you see this? This is two stations the same stations where it looks like over here. This is in Pune So we thought, you know Mumbai could be different from Pune because Mumbai being a coastal city versus Pune being in land a little bit It might be different not really Okay, quite similar. In fact, these are together Mumbai and Pune all together. Okay, notice that there's a little box here The CPCB norms require that always 24 hours a day seven days a week 365 days in a year you should be inside that box Ladies and gentlemen, I present to you India That's where we are right now and things haven't improved very much in the last seven eight years We were also expecting that around Diwali We should have a lot more PM 2.5 Wouldn't you expect it lot of smoke lot of cup, you know Patakas going around people celebrating etc. This is Diwali time Okay, that's Diwali time and notice that this ratio is not you know, it's pretty much same line So what we said what is going on? We were really expecting it to be much higher It seems to be in track apparently people are traveling a lot also during that time So the transport the enraignment of dust all of that resuspended dust is going on But if I were to just isolate these points over here and take a ratio it is higher than the rest of the annual average Okay, so it also gives you that indication that there is smoke at that time. Okay so one more time Just to reinforce why we were doing all of this we ultimately want to qualify the particulate pollutants And the way we've qualified first is by size and then further we went one step further and say look There's difference in the chemical composition even based on size size was based on respiration And then after that What is the part which is toxic versus what is the part which benign that has us defined PM 2.5 and PM 10? Ladies and gentlemen, let's see end of this one Talk to each other get this sorted out. I'm not taking any questions just now We'll deal with it during lunchtime because a lot to cover. Okay, go ahead. Please talk to each other about this talk at this time You supposed to talk at this time Okay All right enough questions in the room, right? Okay, module three All right sizing of particles, it's okay to say okay this size and all that stuff. How the how on earth do you actually size them? This is our normal perception of sizing Yes The first time yeah seaving the first time, you know, my mother was trying to make something in the kitchen and She needed Mehta everybody know Mehta So I used to think as a kid that Suji Rava, right Suji Rava Atta and Mehta I used to think they come from three different grains Don't look at me like I'm the you know, ma'am. You know stupid mistake. I was silly. I was silly. I'm even silly now Okay, I keep having these assumptions around life. Okay, so my mother she took atta in a Chunni Yeah, and you touch it touch it touch it and out came Mehta I said wow my magic my mother's a magic woman How many of you know your mother's are magic women they are I'm telling you yeah, all right good. So This is our perception right This is our perception before what size? We're talking about now particles which are less than 10 micrometers anything larger than 10 micrometers is gonna get stuck in the nose You know how to size them? Okay, everybody ready. I'm gonna do a very disgusting thing Ready I'm gonna do a very Interesting name disgusting thing interesting thing. So sometimes, you know once in a while when nobody's looking When nobody's looking, huh? Nobody looking nobody looking finger It goes straight into your nose Right, you do a little bit of tickling over there, right and something comes out And then of course you don't look at it right because first it could be dark and second you don't want to be so obvious Etc. But you know you some point in time now disposal problem You understand and I'm telling you you guys don't get your handkerchiefs out you want to bet on this Okay, so you you know you see you don't see that but next time I request you to see it I'm not kidding. I'm serious. See typically on a clean day when you have been in clean environment It'll have some kind of a marble green. I've done the observations, okay? Marble green kind of a color you understand what I'm saying it has a certain it has quite quite a pleasant color actually But on a day when you've gone out into the traffic and you come back that whole thing is black It's very dark color. Okay, so you should just know that you know You should thank your nose every time because it's doing his job. Okay now anything which is less than 10 micrometer Everybody okay with that disgusting thing. Yeah, now you really want to get that to your students as well It's not just for you I'm sharing this because I actually do this in the class and you know shared this with the students So they actually get an appreciation of the work of the nose and you know what size actually stopped and what actually gets through so What about less than 10 micrometers less than time 10 micrometer means you can't see with your naked eye now Less than 10 micrometer. You can't see so my mad my mother cannot be a magic woman if I give her 10 micrometer particle size Let's her and say okay now do the sieving. Where is it? I have no idea by the way the sieving requires a certain sedimentation velocity If you take 10 micrometer particles and you put it in the air you'll have to wait a long Time before it settles out You know this you can do them calculations you do a calculation of how long it takes for a one micrometer particle To actually settle out It's a few millimeters in an hour Okay, so you cannot depend on sieving So how are you going to measure particulate matter? That's a class exercise now Okay, so the exercise we do is how would you size and count aerosol particles in the nanometer size range? Okay So we just quickly go over it. So there are different ways in which you do it There are inertial impactors where you use the inertia of an elephant Where you use the inertia of an elephant which is suspended in an ocean of ants So it's very simple. What you do is you got particles of all sizes here, which are coming in and As they come in through the nozzle you actually put an obstacle in the way So these particles are coming all three different sizes. They're coming the gas is coming and you put an obstacle in the way When you put the obstacle in the way the small size particle and the medium size particles They will go ahead and follow this path of the gas, which is the ants So the ants are able to take the small particle and the medium size particles along with them But the elephant the large elephant was too huge for them to be able to kind Move out so that poor Large elephant actually has to go pot it goes impacts against that obstruction Okay, so what did you just do? You took three different kinds of particles Passed them through a nozzle provided an impaction plate in which the largest particle actually went and impacted because of inertia Okay, now the next part of the trick is you go ahead. This is some volume coming in Let's say 30 liters per minute. Okay, so what you do now is you reduce this next nozzle size So if you reduce the next nozzle size the same 30 liters per minute has to go through But this time the velocity will become higher. So that particular particle which could escape here will impact this one Okay, so on and on and on you ten stages you can separate out all the particles suspended in the air in different class different size classes Yeah, so first top most so what you do over here is you put a filter paper Or you put a metal foil and on that metal foil these part This has been pre-weight you waited before and then you run it for say one hour or something like that And you bring it back to the lab and you wait again So the difference in the two will tell you that between this size and this size this much mass was there The next one this between this size and this size there's much master between this size and this size is so on for 10 So you actually get a histogram so on the x-axis you will have The diameter of the particle and on the y-axis you'll have the mass collected. So you have the entire size distribution Yes, okay good next. This is what it looks like it costs about eight nine lakh rupees this instrument It's called booty micro orifice uniform by the way Why it's called micro orifice because these orifices in the first stages are visible By the time you get to the last stages, even if you put it against the light you can't see the hole in it Okay, the principle is not seaving The principle is not seaving the principle is Impaction of a particle because of the inertia Okay, very good. We do some fun stuff. Oh, by the way, this is important You should just know that the chemistry so state 0 is the largest particle stage 10 is the smallest particle state 0 is the Largest particle stage 10 is the smallest particle most of the larger particles have silica Most of the smaller particles have carbon Chemistry for different size particles is very very different That's why this component tends to be toxic Okay, heavy metals tend to be in the smaller sizes. Okay. All right Different sizes etc etc. Oh, by the way, we made one in our lab So if students are interested in making one, let me know we have a paper in which we actually give instructions as to how to get it made This one cost 6,000 rupees 6,000 rupees in a local workshop. You can even do it in your workshop Okay, and it compares pretty well with the 8 lakh instrument. This is ours. This is the 8 lakh instrument But just to be fair. Okay, just to be fair 8 lakh instrument gives you 10 sizes 10 different sizes whereas ours the one we use only differentiated between PM 10 and PM 2.5 Which is fine for us, right? Which we needed because we need to do some measurements. Okay. All right, then optical particle counters You know why you can see a cloud? Because it's cat is light Right if you take water everybody know turbidity Okay So you take one glass of water which is turbid and one glass of water Which is clear and I give both of you for you to drink unless you see bubbles coming out and you think it is you know Limca or something like that. You'll probably have the clear one Right because you suspect that if it is turbid much there's some contamination over there, right? Same thing over here except that we don't deal with it as a cloud We deal with it as particle by particle Single particle single particle single particle. Okay, so each particle will scatter a certain amount of light and That amount that gets scattered is equivalent to the size in some way and each time it scatters It's a beep so you count it and you look at the size of the scatter and say the size Okay, so this is basically what it looks like these are particles which are coming through a little later So this is the detector over here. This is the detector here So every time a particle passes by this laser it actually scatters light and then depending on the particle size You'll have a certain intensity of the light scattered So the size of the scatter will tell you the size of the particle and every time particle passes by that be a beep Beep beep beep the number of beeps is basically the number of particles Okay, this instrument about 8 lakhs 10 lakhs depending on which one you want to buy Last one electrical mobility You charge the particles. How many of you still remember 1 upon 4 pi epsilon permissivity Q q divided by r squared come on Long time ago the force experienced by a particular particle which is charged in an electrical field remember Same thing so the principle is exactly the same What you do is because these particles are so small that they do not have sufficient mobility under gravity Or they do not have sufficient you cannot produce the kind of inertia that is required in the previous Impaction etc so what you do is you charge these and you introduce them into an electric field and then you sort them out Based on that. Okay. We'll talk about details later. So you charge the particles you size them Particle counter we get details later. I'll give you these details later. There are other instruments high volume samplers is something which everybody's very familiar with Doesn't cost too much about one and a half lakhs now Many volume sampler p.m. 10 p.m. 2.5 again based both So this one is based on inertia, but in a cyclone this one is based based on Impaction which we just is impactors what he said and then this last one over here is based on optical properties So you actually this is a particle counter optical particle counter. This one is impaction. This one is cyclone Okay, so this is homework at this point in time. I give to the students Familiar you've seen most of you've seen this cartoon before right So are the assignment is this evaluate the scientific feasibility of the proposed solution by the cartoonist So then they have to go they have to go figure out from Google You know, what is the rate at which we breathe out carbon dioxide? What is the weight ratio? What is the amount of tree required? How much per surface area of the leaf will be oxygen given to me? And then of course the first question comes up at what will do at night Photosynthesis is only at night. Yeah, yeah taken it So this only can work during daytime, but at least for daytime will it work or will I have to carry my own little truck of trees? Carbon dioxide will wait you and I will respire So RS what we exhale it's simple. It's very simplistic, right? But it's interesting that the students can actually get engaged in it, right? So I breathe out because of respiration carbon dioxide that carbon dioxide is taken up a photosynthesis gives me oxygen back But I have to do the matchmaking now because the rate at which I'm throwing out carbon dioxide I should be getting the oxygen at the rate at which I can live right like that Okay, so everybody got this and the second part of the question is what key steps would you need to take to develop an air quality Managing program for your home city You are the collector of your city ladies and gentlemen Okay, so this is when they begin to get engaged in how are they going to figure it out? What is the needed some of it which you covered some which we will cover in the near future But you set up the question accordingly, okay done Okay four of four I think this is an important aspect that most students would have a concern about how do you control these right? Now when we talking about control we now talking about two levels at a personal level and at the industrial level Right, okay, but let's just look at it scientifically. We won't bring in the distinction over here Let's just take a look at what is it that by the way, this is much of chemical engineering chemical engineers here? chemical engineers one that's it So then oh few so you guys are my friends, okay, so if I say something wrong don't raise your hand Now I can just about say anything right, okay, I'm a chemical engineer too, so okay So this is just a brief summary of the principles that are used for control of pollutants Which are in the gas stream if it is Large particles and we can use settling chambers and I'll get to the details of this. This is the principle This is the equipment and this is the principle. This is for particulate matter and this is for gases. Okay, we'll go over it now So particulate matter There are many ways of dealing with it. You can use Mechanical means or you can use electrical means Mechanical means anything which is larger than 20 micrometers. You can use a gravitational settling You just allow the dust to settle Gravity you don't have to do too much. You just have to allow it enough space enough time for it to settle out Okay, cyclones you provide some inertia. You pay for it in the pumping cost You actually have to I'll go over it. Okay So this is typically what a gravitational settler would look like in a cement industry This stuff over here is actually their product So they have an interest in Recovering their product. Okay, so this is dollars over here sitting over here So depending on the size they can separate it out or there could be another way of dealing with it that you do Not allow this huge space This huger space you provide plates which are closely spaced so that's what you do So introduce the dirty gas from here and these are plates So they just have to move this much distance for it to settle out on a plate Okay They just have to move small distance for it to settle out on a plate and then you shake it up and you know clean it up Okay, this is a cyclone Okay, what you do in a cyclone is you introduce the gas stream tangentially So you take a cylinder Okay, and you introduce it tangentially so when it gets introduced it tangentially now it's going to whoo It's gonna go right in a spiral direction and when it is going in that spiral direction the particulate matter Which have higher inertia will get thrown against the wall Okay, so that's what you use you use again the particle inertia, but in a circular motion Okay, all right So then basically the gas the this is typical dimensions by the way look at the efficiency Particle size is given different efficiency. So larger particles Definitely very efficient, but anything smaller than 20 micrometers cyclones are not very good Okay, you can use them up to by the it's a good step though before you use any other kind of high-end filters expensive filters It's a good idea to use cyclones or gravitational settlers to be able to remove the large bulk of the mass Again these larger particles contribute much to the mass smaller particles don't contribute much to the mass So you can remove the bulk of the mass, but the finer fine polishing can be done using other instruments like other Equipment like bag filters and electrostatic precipitators. Okay, so this is this is the size it could look like this size They're pretty huge. Okay. They're pretty huge Mechanic ah mechanical filtration. Okay. This is where my handkerchief comes into play. I'll come to that I think maybe I should show some pictures you familiar right Seen these you've seen these right in some way or form you've seen this if you haven't you've used your handkerchief Left a lot of times right to say it's too dusty a lot of times you don't do it because it's just you do it because it's smelling bad Usually, you know, yeah, okay, and hopefully your Hunker chip would you would have put a little bit of perfume in the morning or something like that So you neutralize that bad order or something like that But you know, but this is more for oh, this is another one very typical This is a some kind of a metal clip that you put on the nose and you just tighten it over there This is my favorite It actually has a little Glue strip over here. So you just have to remove it and then stick it on your forehead It's pretty good. It's good when it also says just peel and seal Nice jingle to it. Nice peel is in nirma washing power to nirma like that, right? So peel and seal and it's one child mask and it tells you easy to apply a multi-purpose pocket side No straps. It protects eyes. It allows you to be clearly clearly see eyeglasses compatible Antifoxy all that stuff fancy stuff Okay, all from Google by the way. Oh, I don't know what this guy is doing He seems to be standing in an in a stadium an indoor stadium Why would he be wearing a mask instead an indoor stadium? I don't know So I that I found a little funny as to why he was using that but these masks over here Okay, these masks are used in industry They use their industry to protect the workers Okay, so for example if somebody is working in an ammonia based fertilizer plant then people are going to get exposed especially if there's a leak or something's going on then they need to actually go and You know take care of it, but they have to protect themselves. So these cartridges then are not just fabric They actually have some kind of a chemical in it some kind of a gel in it Which will tend to neutralize that particular gas which is expected So for sulphur dioxide, it would be a different cartridge for ammonia. It would be a different cartridge Okay. All right You've seen these filters In taking to the car right and these are serrated like this large surface area is required. Otherwise the Delta P would be very high. Oh By the way, this recently there's somebody who approached me with the new product It's like earplugs You know earplugs are soft earplugs, right? This guy actually had nose plugs Which I thought was pretty fancy The only thing is I refused to try it because I said it'll make me feel like I have a cold So I'll start breathing from my mouth Okay, and we I've been trying to give this project as a student project for the longest time as an m-tech project for The longest time but nobody seems to want to take it I wanted to design a crash helmet which is used for motorcyclists People on two wheelers to actually have a filtration device because I think people on two wheelers are most exposed People in a car. They don't get exposed to the traffic, you know Pollution but people on two wheelers get exposed But the problem comes in that the moment you put a filter over there They actually have to provide the lung has to do extra work to suck through the filter paper. You understand, right? Everybody at some point in time. You've had a cold drink with a straw Okay, now next time you go to have a cold drink. Just put a knot in the straw and then turn Okay, so the same thing would happen here if I put a nose plug over here. I'll have to breathe through that It's a lot of work on the lungs So I'm not too sure but we do we are still looking for some effect. These are not very effective The moment there's a little bit of a leak around the face over here The air will find the easiest path. Why will it go from you know a more difficult path? So there's still a little bit of work to be done around that So therefore the surface area needs to be higher if the surface area is higher in the pressure drop is lesser Okay, that's the reason for it These are different industry scale. They actually have bags. It's like a Lexox but instead of having a bend like that it is straight So you actually can introduce the air either from the inside or from the outside and then from time to time You have to shake these bags. They're actually bag houses big bag houses So if it is from outside so that it doesn't collapse They have to have a like a support shell in from the inside There are different ways of dealing with it People are even interested in the computational fluid dynamics around it to look to see what are the flow velocities and temperatures Etc etc so that you can have an efficient bag house. This is like a typical bag house many many socks hanging over there in a box in a shell This is what it looks like in real Ah, this is typical the size of an air pollution control device in an industry Look at the size. I think students need to get a sense of it if you can take them for an industrial visit. It'll be fabulous Because I took you know my students we do it as a part of a course always We took them to Tata power plant and they actually got a sense of how big the electrostatic precipitate is the size of this hall I mean a good 30 to 40 percent of the capital investment actually goes into Electrostatic precipitate is they're very high-end equipment. Okay Okay, this is now whenever I want to talk about fibrous material fibrous material is not seething Okay, everybody understand this my handkerchief a lovely handkerchief, right? Everybody handkerchief handkerchief. Yes Okay, typically what I'll do is I'll do this and tie it up, right? If I'm going to a Burudwara I do it the other way around, right? Okay, so like that you do now does it help? This air coming from here air coming from here. It doesn't help very much. I went to IPL At some point in time there was Naguthane They were having a course so we were talking about and I said lies you deal with powder a lot So I told these guys if you deal with a lot of particulate matter, right? He says, huh, I said, what do you do? How do you protect it? No, no, sir. I was mask. I think I should be clear. I'm not like you. How do you do? How do you use? So it says, you know, sir. Actually, no, it's not very good But what we do is we make it wet and after making it wet is very effective I should really says yeah, I said, okay, bring me to next time. So he brought to next time and we actually took one and I The dry one and we put it against the light and we couldn't see much of the light through it You understand right if you take a handkerchief, right? And I looked look at light like that through it I'll see a little bit of light diffuse light kind of a thing the moment we wet that mask and then looked at it It the light could be seen clearly So which one was more effective? the dry one Dry one. Okay. Now the the understanding is where the issue is You are not when the particle is going through this fiber through this fabric, okay, it is not going as a seam It is actually following getting into an Amazon jungle Where there are these lot of these fibers fibrous material around it, etc. It has to go this way. It has to go that way at some point in time It will diffuse to a surface or get attached to a surface It is not going through like it's okay. Let's go walk through the no. It's not like that, right? So the moment I wet it The moment I wet it a lot of these threads which have the fibrous material all over the place Okay So everybody understand that the moment a particular thread in that particular thread when these fibrous material because it's wet Because it's wet they can to tend to get stick that then to stick to the main body of the thread So there is that Amazon jungle has suddenly become like a clear chaika mesh Okay. Now I want to qualify that if the pollutant out there is gaseous and If it has affinity for water, which means that it is soluble in water It's a good idea to have a wet handkerchief or have a wet mask Everybody with me? Please don't mix up the two things. Okay, ants different from elephants If ammonia molecule is there and it has affinity for water by all means wet your handkerchief But if you are using it for dust Not a good idea because the wet Lint will tend to collapse on the main thread and it'll clear passages So it takes away the tortuosity of the particular mechanism so the mechanism of Mechanical filtration is the tortuous path that a particle has to go through the Amazon jungle everybody with me Okay, very good. We can be coming to a close very soon. All right, so that's just a repeat electrical again You use charge a particle and you put it in an electrical field. Okay, you use that and these are huge again The size of this room I said That's the principle for it. This is the size Gases absorption which is I just said ammonia for example has affinity for water. So during monsoons During monsoons the water which is falling from the sky the rain actually does a good job in scrubbing the gasses It actually takes away the pollutants both the particulate matter as well as the gaseous matter. Okay adsorption Activated carbon everybody knows yeah, okay a lot of times activated carbon in you is used in these cartridges also Because it tends to absorb the hydrocarbon that has an affinity for hydrocarbon. It's a surface phenomena. It's not a dissolution It's not a solubility phenomena. It's a surface phenomena incineration Lot of times at night if you're going in a train somewhere you see oh there like you can see a flame over there And you know there is some industry over there and why are they wasting this gas? They could easily have gone, you know taken it and used it somewhere. No, they can't Thermodynamically and from a process perspective. They cannot use it beyond a certain point So they have to so instead of letting it out as hydrocarbons They're doing a responsible thing by burning it and if you burn it nicely it'll get converted to carbon dioxide and water Otherwise as a hydrocarbon it can cause more damage. Okay So you can use me DJ so this is absorption that the absorption towers could look that tall Okay, students need to get a sense of the scale Really need to get a sense of the scale. This is the kind of scale, okay? In a barge It's huge It's a part a very small part of a larger more complicated process So the challenge is to be able to interface it in a way in which they work well together Okay, this is adsorption by the way, there are these local. I think I've seen more applications of adsorption in water Have me have you come across they use it as a polishing step also in the in the as the last step and before they put it In the distribution system, okay incineration See the flares at night Okay, now this one is pretty good, okay This one is pretty good you can hardly see the flame which is good if it's invisible flame very good That means oxidation is very nice But this friend over here This one not good It's not enough air being supplied for complete oxidation. Okay. All right This is what a typical top of a burner looks like it can be multi-port from different parts of the process industry It could have one inlet coming in which gets burnt So they have one common point where all of it is getting burnt. Okay, so it could be looked like this Okay, this is on a typical oil rig where they are trying to deal with bringing a new well into activity So they have to get rid of the oil which is mixed with mud never a clean operation They can't have a clean operation because a large part of it is mud so but you know, they need to Responsibly dispose off this particular oil and gas Okay, I'm going to take just a couple of minutes and complete at this point in time All the information that I could have given to you is given to students Okay, everything given now is the time when they'll actually have to deal with Playing a role and the role we said is that of a collector. All right So we say, okay, there's a science over here, which we understand But then the question is it's not going to come into play till you have a certain accountability around it All right, so let's say home. You're the collector of the city. You are the Please say you are the everybody say See it again Because some people are you know don't see all colors Okay, get the point. Okay next you you You okay, got it anyone more you know, that's it. Okay So, you know, you just want to do a little bit of fun so that students can actually Get the sense of that. Listen. This is I am being addressed as the collector and this is my accountability now So you have to kind of bring that game a little bit of you have to be playful, okay? You know this by now if you haven't got it by now. I'm taking the next one and a half a session also No, no, no, you want Harish. Where's Harish is you know, okay? All right. So as a collector you first collect historical data So for Chandrapur, this is the historical data for the last 10 years Okay, based on this you'll have some sense of what how's the air quality doing if it is already good Have a good time do other things as a collector But if the air quality is bad, then you need to take steps to be able to deal with it So then we'll have to look at location of the sources. There are point sources line sources area sources You need to get a sense of where are the sources in your geographic area? So this is a mines over here. This is the industry over here, etc. You get a sense of where it is, okay? predominant wind direction Then you develop an inventory How much sulfur dioxide from where how much oxides of nitrogen from where how much carbon monoxide from where? How much PM from where using emission factors? For every activity you have a sense of how much is being emitted by a particular activity So for every megawatt of coal-based power plant production of energy of electricity, how much carbon monoxide is allowed? Okay, so you'll get some sense of that using a and then this is typically been done at a 500 meter by 500 meter resolution Especially in six, you know six large cities. We had done this You understand half a kilometer by far half a kilometer You know exactly which source in that half a kilometer by half a kilometer and how much it is emitted Pretty good, right as a collector. You are the boss Collector's everybody Hello collectors We acquire the meteorological data. What is the meteorological data? Wind speed etc etc, right? So you get that then you use a dispersion model to estimate the pollution isoplets So you could do it on a daily basis. You can do it a seasonal basis You can do it an annual basis you won't do it But you will hire some engineers who are trained in air quality to do this for you But as a collector you want to know what we sure that this gets done. Otherwise, you can't make a decision Business as usual versus benefits from it. So if you were to take an intervention See as a person who's a decision maker I would say listen if I shut down this industry will it make a difference just have to go to the model and it'll be able to Tell you how much of a difference it'll make Because for example in Chandrapur, they shut down the industry. It still didn't make a difference with the air quality Then why shut down the industry? Kind of okay good Which source is affecting larger population etc. So those questions, okay? So if you've identified the culprits Okay, then you can shut down the industry and ask people to stop cooking Why stop cooking because a lot part of the Chandrapur problem is coming from cold cook stoves Which 50,000 people are using in the morning 50,000 people are using in the evening and that's there That's the only way there's a certain level of poverty. They can't afford anything else. They use this This is available for them and they use it right so you can't do that So simply said whatever I said as a large plan collector's plan correct simply said It's gonna lead to unemployment. It's going to ask people to start grazing, you know, I mean you oh next elections will be lost There are implications you and I are pretty aware of it It's just that you and I probably don't have the wherewithal or you know, we don't have you know The the training or the thinking to be able to but these are the implications which a collector will have to deal with Right, okay, so that's just review. I'm just saying historical data. Can you get this data right away? Will they give it to you? They'll not give it to you. It'll take six months to get this data. Oh by that time the collector will get transferred Okay, okay, then you know location of the sources There are places where people won't let you come into the 500 meter by 500 meter because they don't want you to know What they're doing there some of the recycle reuse industry for lead batteries for example No lead no lead being thrown out from there But you they don't let you go in there will ask river especially in water will ask river Valduni there are places where some dying is happening some genes dying Okay, it's very highly polluting in industry water industry. They won't let you win That's a huge mafia in place which will not let you even go in students also can't go in Okay, so it's not that straightforward to say let me find the location of the sources whatever is reported Whatever is in the organized sector. I can deal with probably probably probably However, which is not in the organized sector is very difficult. So you know this one Yeah, there are always what numbers do you get? Do you know do you know the exact number of cars probably from the RTO office? You can get it, but you know, there's always a lag between what's going on and what's actually the case so 500 mile 500 meter is a very ambitious Resolution okay, but we did it as a part of six city study. There's a lot of investment That's required for us for an exercise like that. So you as a collector of Chandrapur may not have that kind of a resource available to you Meteorological data. Oh, let's just quickly look at this. So but you know, there are these three IMD stations and When I compared the wind roses, they look pretty good wind roses similar these two places similar these two places similar So three places one two three on at almost a 200 kilometer triangle Pretty similar, but it when it comes down to all three being similar when it comes down to Chandrapur For some reason that particular wind rose is very different. Okay So you and I therefore become responsible to make sure that the data that is going into the model is Accurate because this over here clearly is going to define the entire future of development in Chandrapur and Clearly in this particular case this data being used is wrong So we looking doing some work and it's not their fault. They do the best that they can It's just that sometimes, you know, they don't realize what's going on. So we actually have done some work to Look to see that there are two other stations over here And we're comparing to see whether see if One here one here one here 200 kilometers apart. They are similar on an annual basis I don't see what's so peculiar about this particular one that has to be different is right in the middle of that angle Wind suddenly can't say oh Chandrapur. Let me go this way. They don't do that, right? So he compared with some of the other Stations over there these look similar But you know that particular place which is being used for all the modeling work in Chandrapur is different So we are inquiring into what's the correction to be made over there? Okay, so holistic viewpoint we need to take and you know We need to just do the diagnostics to see If this is what the industry is claiming that they're polluting and say even if they're lying Even if they're bad people, they're giving you all lies. They're under under reporting etc. Let's say even if I double it Even if I double the emissions that are coming from there, they're not reporting etc Still I cannot account for a good 40 to 60 percent. So Chandrapur, which was the fourth most polluted city 500 crores 400 500 crores spent on it. It went from fourth most polluted to the second most polluted What happened was the money, you know, did it go in the bad places? No, it actually got used But they were not working on the issues that were actually causing the problem So we need to actually look at what is really causing the problem and they also found it If the industry shut down that it didn't affect the pollution levels at all It was affecting but 40 kilometers away 30 kilometers away because the chimneys are tall. Okay. All right Some other things that you could do recent efforts be using satellite data to be able to compare Satellite data is really great fun. Okay at some point in time. We should probably just have a workshop on satellite data Okay, it should be fun Episodic event you actually use an episodic event where you say, okay This is the time when the plant was shut down for three months April May June three months. It was shut down. So we compared with the previous year and the following year for the same month Clearly there was a Contribution coming from the power plant But interestingly again locally what you and I were breathing in Chandrapur. It didn't affect at a regional level It affected but at a local level it didn't affect because there are more chulas and dust over there Which are affecting it rather than these industries Okay, you know I do a little bit of work on this solar But this pretty much gets covered in the movies and inconvenient truth pretty much covers this whole in concept of the Global warming etc Then you know not all gases are equal So you actually can compare different planets, etc. And this is co2 levels Global warming potential carbon monoxide carbon dioxide versus methane We can get to the details of that energy what I like the last thing I want to leave you with is Human beings are a hundred watt machines So there's a label which said hundred water machine So human beings are hundred watt machines So I also give an exercise to the students to look to see if you were a hundred watt machine What would it take to sustain you just from a perspective of overall energy consumption, etc. How every time you Get a milkshake People love milkshakes at the time I used to love milkshakes when you when your milkshake is being made for those 15 20 seconds You know how many servants are working for you Typically this 1200 watts machine 1200 watts So there are 12 servants working for you are the emperor or the Empress at that point in time because there are 12 people over there Waiting making milkshake for you You get the point It's a little you know So students actually enjoy doing that exercise of saying okay You know how many cars if you go in a car if you go in a scooter, right? How many people are actually carrying a little pal you know chariot or your little palki. So those kinds of things you can do Okay So this are some of the other activities and this is the last slide. I think Bhopal gas leak. There's a film. I'll give you the link for it. There's another short film smog incorporated There's a video she ran J. Ram Ramesh had come for a talk over here with students So it's a good at that time. He was a minister of environment and forest. It's a lovely video You know, I think you should share it with the students then in based on that I give question to the homework also notice my homework so all around videos and all stuff, right? So people have actually and says what are the key issues of environmental protection governance for India? That she J. Ramish highlighted in this entire session and there What is the call to the youth of the country there in because the point is that he was actually talking to? The young students at IIT at that time. This was in 2010 All right, happy seasons depending on the season. I also introduce a couple of slides So if it's just before holy, I wish them happy holy and then tell them look out for the Particulate matter in the air right and if it is And same thing for the valley so then they you know, it's conscious. Okay, ladies and gentlemen time for lunch I'm available if you have any questions, please. I'll be you know here to answer any questions Okay, thank you. Have a great lunch. See you soon