Air Pollution Part II

Aug 9, 2021 07:20 · 3612 words · 17 minute read

today we are going to discuss about how we can control the air pollution so there are various methods and there are various ways how can we control the pollution depending upon the individual approach or collective approach first and important is use of mode of transportation you know in this contemporary world in this modern times we mostly use the vehicles which are driven by petrol or diesel or some uh are also driven by the other kinds of fuels like uh gasoline like gas lpg and also electricity so we have to encourage more and more people for using the public transport public transport in the sense we should avoid using our private vehicles using uh the public transportation like sharing taxis cars carpooling if if we are going to the college uh if we are going to the office we can use car pooling so by that we can reduce the exhaust emissions from the vehicles which mainly comprise of particulate matter nitrous oxide so second one is the conserve of the electricity so in this modern times the electricity is mainly generated by the coal and fossil fuels like in thermal power plants the electricity is generated from the burning of the coals and producing the steam so if we conserve the energy so there is a less need of energy generation and that can uh reduce the use of for the fossil fuels so how can we conserve the energy first of we should use in li uh energy efficient equipments nowadays most of the equipments like the bulbs they are very efficient in comparison with the kind of lighting equipments which were used a decade ago so we can switch off the fans uh we should reduce the use of uh air conditioners that can reduce the use of electricity and that also can in longer term reduce the use of fossil fuels and we should also understand the concept of reduce reuse and recycle basically this concept is when an equipment is seven uh material is purchased from any store that equipment has been produced from some industry and that industry uses various kinds of energy and that energy can be driven by from the or drawn from the fossil fuels so if we reuse and uh if we reduce for if at first instance we reduce the use of certain things and if we cannot reduce at least we can reuse and we can recycle like we are recycling the papers same in the same manner we can recycle the various equipment so there is less need of production and there will be the less generation of need of less generation of energy for producing those equipments and in turn that can reduce the use of fossil fuels and next one is we should give emphasis on the cleaner energy resources in the second unit of this uh module course we have discussed various kinds of energies first we discussed about the renewable energies like solar rain geothermal energy what are the how can we use those kind of energy so we have discussed that already so this kind of clean energy resources could be used only when there are policy interventions from the government there is the provider means government can make the availability of the equipments in the market at subsidized rates so that the various kinds of industries or even the commercial and domestic level uh the people can purchase the equipments so that they can get energy from those resources like solar we because uh solar we can use at home for our small needs but uh when we say about the wind and geothermal energy this needs a large setup large of capital investment so government interventions are very important in here and uh as i said earlier use of efficient devices like cl bulbs were used like rods for use they were more efficient than intended lamps that were used before having the tanks inflammant but uh in recent times we are using led light emitting diode lamps so they are very conservative in terms of energy they can reduce the electricity bills so beside that uh there should be a proper environmental impact assessment that is not mentioned in this slide uh basically when any industry is set up there is a survey that kind of baseline survey if the industry industry is uh installed at a certain place what are the environmental impacts particularly the air water and other soil pollution so in respect with respect to the air pollution if for the environmental impact assessment is done properly and what are the mitigation measures that industry can take if the air pollution is very high so that is very important we can go for the environmental impact assessment and uh they we can uh for uh various kinds of industry which have the stakes like chimneys where from the gases are emitting we can increase the height so that there is a dilution uh of the pollution but that also have a problem if the stake height or a chimney height is increased that uh causes the interstate kind of pollution that creates a dispute between various states if the height of the germany is increased then the spread of that pollutant or gas is very large so the pollutants get spread out to other states also that creates problem so these are the primary some important points how can we reduce the air pollution there are also n number of for the ways how can we do it is like we can go for a forest ration we can use biological filters like plants they act as a biological filters we uh shifting to the cleaned i have discussed here the solar wind and geothermal but also there are some other fuels like hydrogen gas which can be used uh as an alternative for the energy resources for the vehicles so these are the some important uh ways how can we reduce or control the air pollution but at industrial setup uh there are various equipments that are have uh are installed uh for reducing the pollutants so air pollutants in a year when any pollutant is released it is in the form of gas like sulphur dioxide nitrous oxide carbon monoxide carbon dioxide these are the gaseous pollutants besides that there are also particulate pollutants like particulate matter 2.

5 2. 5 means 2. 5 micrometer is a diameter of that pollutant and 10 micrometer so these i will discuss what are the limits what are the standards that can be uh that have to be implemented in industries so that there is a reduction in the air pollution so first equipment that can be installed in any industry that is the gravity settling chambers this is kind of equipment where the gas is given a time to pass uh any uh space like this is a column so when the raw gas raw gas means the gas containing various kinds of pollutants like particulate matter is the mainly main equipment which is used which is reduced in this uh equipment so this uh is a raw gas containing high particulate matter load and when it is passed through this length it takes it it has much time so that the particle gets settled down in this hoppers through the action of the gravity here the particles size more than 50 micrometer micrometer is uh if we make uh 10 lakh parts of one gram uh one meter ten lakh parts of one meter so that is one micrometer so that is 50 micrometer uh or the larger than that 50 micrometer the particulate matter can get settled down and after the exit gases have less amount of particulate matter so we can collect here and we can dispose of that safely to the places where it can be stored or where it can be used for other purposes and next is the bag filters back filters are basically uh the bag contains a large amount of filter bags made of fabric they are hung upside see they hang upside down and in several compartments of a backfiller because this uh these compartments are made up of fabric this one this lining they are made of fabric when the draw or dirty gas passes through this containing the particulate matter so in this course the air gets faster but the sparkly metal gets settled down you cannot pass that fabric pores so after a while when this particulate metal gets separate on this fabric we can shake this uh by a certain equipments or a shaker then this particulate matter gets down by the gravity and we can collect this dust here so the fabric used is a polyester polyamide or teflon kind of uh material which can be used for the bags the next one is the cyclone collectors cyclone collectors are basically the equipments which make a vertex like i when you ask if you have seen in the pictures the cyclone which makes the worlds around the low pressure in the same pattern when we pass the dirty gas and it makes a cyclones so that through the centrifugal force this uh india particles get settled down or they get sticked to the to the walls of the cyclone uh chambers and the clean gas gets uh exhaust from the top so this uh this particulate matter gets uh collected in this hopper so we can collect it from the basically this is a air which is making a circular round around and this uh circular arm creates a centrifugal force and this centrifugal force makes heavier particles to settle down and make clean air to pass from the top of the chamber as an outlet then is electrostatic precipitators it this concept is basically uh based on the principle that particulate matter has a charged property they can be negate you or positively charged so in a chamber we use a plates they are positively and negatively charged and when we pass the gas having the particulate matter so these particles gets attracted to uh towards opposite charges and they get a stick to these plates having the charges like if the particulate matter have negative charge it will get it will get stick to the positive plate and it leads to the uh ear clean uh from the particulate metal and later on we make these charged particles to neutralize and we can collect the particulate metal from the bottom of the plates so these are some basic equipment and one and most important is the wet scrubber scrubber is basically removing something from the gases it can be particulate method or it can be any gas also so here dirty gas is passed from the blow and when it rises up so we spray the water assembly we spray the water and with water particulate matter get dissolved not dissolved but it get it gets wet and it increases the weight of the particulate matter and it gets down by the gravity and also some gases also get dissolved in this water like carbon dioxide sulfur dioxide nitrous oxide they also can be collected from this water and there is a one membrane kind of where the mist is removed because when we uh mix this gas with the water it has some water vapor content so we have to remove that so uh this clean gas having the less harmful gases or particulate metal can be uh directly emitted into the atmosphere so by this we can remove the ammonia sulphur dioxide nitrous oxide or also the particulate matter so these are the some equipments which are used mainly in the industries for controlling the air pollutants but there are some criteria pollutants also so criteria pollutants are those pollutants which have been notified by central pollution control board in 2019 earlier there were six criteria pollutants but they have notified more parameters as in criteria pollutants they are now 12.

so there is particulate matter 10 percent matter 2. 5 nitrous oxide sulphur dioxide carbon monoxide ozone ammonia lead nickel arsenic benzoprene and benzene so these are the these are the criteria pollutants if you are asked what are the criteria pollutants basically they are the pollutants that that have been notified by the uh central pollution control board and the standards of national amber air quality standards so for these pollutants the national air quality standards have been notified by the central pollution control board so these pollutants also uh make a crop base for calculating the equality index so we will be discussing air quality what is air quality index in next slides so basically air quality index is calculated on percolate method uh 10 and 2.

5 sulphur dioxide nitrous oxide carbon monoxide and ozone and uh it had been said that more parameters will be added same like uh they have been added as a criteria putters so if we uh talk about the criteria pollutants uh particulate matter to 0. 510 they are major sources are from the motor engines like vehicles industrial activities like thermal power plants smokes they are can be released by any kind of source like burning of biomass or brick lanes or any other source so we calculate these two on the average basis for the 24 hours means week ah major uh one we take one trading for 24 hours so for particular to 2.

5 the standard level is 35 microgram per cubic meter means one in one cubic meter the concentration of particulate matter 2. 5 should be less than 35 micrograms means and 35 microgram is the limit with the standard it should not be more than 35 micrograms per cubic meter if it is more than 35 that the year is polluted so for 2. 5 it is 35 and for particulate meter 10 it is 150 micrograms per cubic meter so the health impacts for these two are different because particular 2.

5 have less diameter it can enter in the respiratory tract and can cause cardiovascular diseases and it can cause central nervous system disease that reproductive dysfunctions and also can lead cancer like diseases and next one is the ground level ozone which we also got a bad ozone which mainly is produced at signals at roots in presence of sunlight if you really can recall it’s a secondary pollutant it is basically caused from the vehicular exhaust and industrial activities and we calculate it on average basis per hour and its concentration should be 0.

12 micro milligrams per cubic meter and it can cause respiratory and cardiovascular dysfunction and eye irritation for on humans but it also have impacts on other infrastructure and plants also then carbon monoxide it’s mainly produced by motor engines burning of coal oil or wood industrial activity smokes basically it is produced by the incomplete combustion of fossil fuels or biomass it is also calculated on hourly basis and its concentration should not be more than 35 milligrams per cubic meter here is micrograms means it is very less uh means a small amount have very large impact but carbon monoxide still as compared to this one it is uh concentration if it is higher it’s still manageable 35 milligrams per cubic meter and it also causes impact central nervous system and called you vascular damages then sulphur dioxide is one and only important uh source is the fossil fuel burning basically the coal burning so it’s also calculated in our hourly basis and 75 micrograms per cubic meter is the standard level and it also causes a respiratory central nervous system involvement and eye irritation it also causes acid rain same nitrous oxide also cause acid rain fossil fuel burning and vehicular exhaust is a main source and also the standard level is 100 micrograms per cubic meter but it can besides producing the acid rain it have the impacts on liver lung spleen and blood lead it’s basically leads melting basically the smelting industries and industrial activities that roll added petrol uh tetra 8 high lead we use in the two-stroke engines for improving the efficiency of petrol burning so it’s calculated on three months average so its concentration should not be 0.

15 micrograms per cubic meter so we calculate on three months average but when we calculate per cubic meter we calculate per cubic meter for three months so it also have hemoglobin for dysfunctions eye irritations and an exogenous system mostly uh all these criteria pollutants have direct impact on central nervous system then polycyclic aromatic hydrocarbons it’s also caused by the fuel combustion wood uh vehicles it’s calculated on the yearly basis and its concentration is uh standard level is one nanogram nano is 10 raised power minus nine and micro is 10 is power minus six and uh per cubic meter it causes respiratory central nervous system involvement and cancer so all these criteria pollutants when we meet and uh on the chart the concentration so in air quality index is basically calculated from the scale of zero to five 500 000 to 500 in between there are various categories six categories first category is good when the concentration of air quality and the air quality index is 0 to 50.

if it is 51 to 100 then it’s satisfactory and 101 to 200 it’s moderate and 201 to 300 it is poor and in poor very poor category it is 301 to 400 and in severe it’s around 401 to 500 so mostly if you can search on the google air quality index you can get global overview what is the air quality index in most of the asian or european north african cities we can also get the air quality index of the srinagar uh from the german kashmir state pollution control board which is located in raj park so they also provide a real-time air quality index so in green uh for every criteria pollutant there is uh the range if range increase the color also changes so for particulate matter is up 0 to 50 like uh in particular matter 10 and 2.

5 it is 0 to 30 so all these criteria pollutants when we calculate them as an average on hourly basis so here it is important we use micrograms per cubic meter except carbon monoxide we use milligrams per cubic meter otherwise for all these uh except carbon monoxide the standard will be the microgram per cubic meter so after when we calculate the air quality index so this is like this uh make the average of all the standards uh standard here for example at particular location part plate method uh 10 maybe is from 0 to 50 but it can be the particulate meter 2.

5 maybe 60 to 90. uh same uh nitrous oxide can be more uh one for example 180 to 280 uh lead maybe zero to 0. 5 ammonia may be zero to two so we make an average of every uh criteria and then we arrive at a particular figure and after we consider that the air quality index is good or bad if it is 0 to 50 uh air quality is considered satisfactory and air pollution poses little or no risk to the health of the humans animals or plants if it is moderate from 50 to 100 air quality is acceptable however some pollutants there may be moderate health concern because it is an average there might be some pollutants which may cross the threshold level which may be very severe but other pollutants are from in the good range or maybe one or two pollutants may be in the severe or very poor range but it makes some pollutants may cause the health impacts same from 100 to 100 151 it can cause some members of sensitive which are substituted certain pollutants make experience some health effect like the asthma patients so unhealthy uh 151 to 200 every uh me every person maybe it is an old age and uh or a healthy one may experience and health effects like they can cause headache eye irritation or any other the symptoms and in very unhealthy warning condition the entire population is affected so there is no uh if a person is having disease or not every person is impacted so in hazardous the population is advised to stay indoors till the air quality index is improved so most of the air quality index is increased i mean it gets worse particularly in winters because there is a temperature inversion the pollution gets trapped in the lower atmospheric levels and it produces more a concoction of various pollutants it can create create and serious health impacts particularly in cities like new delhi where uh the impact of the vehicle pollution as well as burning of the crop residues from the neighboring states like haryana and punjab it creates more uh i mean it increases aggravates the pollution level of various pollutants but particularly the particulate matter 2.

5 and 10 2. 5 is very dangerous and because of that they implement the operating scheme for the vehicles that is less uh impactful because the more the pollutants which travel from interstate are physically the burdening of the crop risk there should be a proper disposal of crop residues of the after the harvesting of the crop.