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Mineralogical Characterization of Original and Activated Ash Samples

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Video 1: Original and Activated Ash Samples
So just to give you some example of what type of R and D has been done until now, we startedworking on activation of slides and flashes.I think I cited this example sometime back that when contaminant geomaterial interactionoccurs at elevated temperature in the presence of some chemicals, the geomaterials get altered,alright.So, what we did is whatever happens in nature, we try to simulate in the laboratory.So, I took sodium hydroxide and I boiled it in a pressure cooker to start with my research,because I am sure you can realize why because it is a autoclaving, which is going on ata very high pressure due to the stream, and achieving very high temperatures.So, what I have done is I have ripped off the external surface of the quartz by applyingvery high temperatures and very high pressures with sodium hydroxide, sodium hydroxide isa chelating agent.You will learn about this once you are into this industry.It basically scrubs the surface of the quartz.This type of activity is also going on in the reservoirs and the ponds where the flyash is being dumped.So this was my Ph D students thesis in 2001 2002.Everybody was talking about utilizing fly ash for making embankments.And we were thinking in a different direction and I said, Look, wait a minute, Let us tryto analyze the samples of the flyers from the pond and the published interesting papersshowing that this material should not be utilized for making the amendments and the reason isfor this about to follow.So, if you take the original ash, you will find that we have quartz, mullite and theseare what known as zeolites.Activated state of the minerals were sodium alumina ratio is in some order, alright.So, this original material gets, you need not to write these is all R and D ideas, youcan read the publications on this, we have written a book by the way on this.I will talk about that.And so, once you boiled with sodium hydroxide this is what happens this is what is knownas activated flash activated fly ash that is a catalyst.So, this is what the after effect of activation is sodium hydroxide is of the fly ash.This processes keep on happening in nature.So, most of the rocks.To my surprise, which I was dealing with a consultant for creating the buildings andthe bridges, particularly one in Bombay huge bridge.There was a bug in the mind and let us see microscopically what type of minerals theserocks have and what would be their bedding capacity, because bearing capacity is a macroterm.Now when you look into the mineralogy.You realize that these type of minerals are not fit as a load bearing mineral becausethey are hyperactive.They will be sucking a lot of moisture either from the atmosphere or when they come in contactwith the water bodies.This is how it looks like.So, from this point onwards, I always tell my students that I am venturing into sukshm,you understand?What is sukshm micro Nano so this is R and D is because until now the conventional theorieshave been talking about the macro systems never went into the microscopic scales andthe Nano scales to understand what causes turned to the matrix of the side.And that is where these tools you know, SEM and that XRD become very, powerful tools.So, the original ash samples would look like perfect quartz balls and depending upon theopaque or the transparency of the balls you can make or what type of mineralogical compositionthis system would exhibit.This is a very different world, you will realize the more you focus on the particles the moreknowledge you get about it.Remember, this material is getting created because of firing in furnaces at the powerplant.So, the coal which you bring to the power plants you pulverize it and as a pulverizedcoal it is injected into the furnace.It is not the coal which is used, because you want to enhance the surface area by pulverization.And once the surface area of the each particle of the coal increases calorific value increasesthese are techniques whenever you get time please go and visit a power plant try to understandhow the power is produced.So, all these fly ash particles which remain in the boiler units or they could be the bottomedge also they tell different stories so, you have turbines from the color you can makeout beautiful thing which I wanted to show you is a sort of a cup inside a cup.You take a football and cut it.So, you have the inner surface and you have the outer surface.Something of that sort you keep two cups one over each other.So, what happens?A cup is sitting inside in the cup one ball is sitting inside the another ball.We call them as Clearosphere they have very special utility in todays’ chemical engineeringprocesses.I mean, if you check on that, you will find that these type of entities are used for makingbulletproof vehicles, bulletproof you know clothes and so on.Because their tensile strength is extremely high.These are perfect quartz balls.In sports, most of the gadgets they use cenosphees and Clearosphere.You know, if you go into the chemistry of these type of particles, you will realizethat during very high temperature when the fighting was done, these particles, the silicagot melted.And then in the stack from where the emissions take place.These particles could not go outside and they have to drop down.We were talking about hydrometer test today morning.It is something like hydrometer test which you are doing in a stack of a power plantwith all fumes at very high temperatures, and particle is dropping down.what type of alterations the system undergoes.So, in the process what happens is a lot of air gets trapped in these particles.So, when the air gets trapped in the particles and they recrystallize they become Clearospheresor cenospheres.And as I said they have a lot of applications,Then I started growing different types of minerals on the particles of quartz or thefly ash particles.So, what you are observing here is the, the, you know, culturing different types of mineralson the surface of the quartz to make it more hyperactive.So, this was the work which was done by my students, Dr. Kolay, Dr. Nevin and Dr. Jhathese are the guys were published at least 50,60 papers on zeolitization potential offly ashes and their applications in environmental clearance.So, remember, when you are dealing with the quartz ball it is inert.But I have used quartz ball to create different type of protrusions on the surface, whichact as a sort of a filter, sieve molecular sieve we call them.Which will have a very high affinity towards cations so any cation when it comes in contactwith these materials to extract over there, because of very high cationic exchange capacityand surface area.So, these type of systems are quite required in modern industry particularly, when youvalorize the fly ash, fly ash which how lying as an unused unattended material has beenconverted into a catalyst.And I can use this as a bio fertilizer also.Because tomorrow micronutrients and the bacteria and microbes will you know come in contactin these protrusions and they will live over there.So, imagine a soil which was earlier barren have rejuvenated.So, these are the concepts that people are trying to work on the industry.This is where the, you know, interesting ideas are in r and d and applications, read thepapers by Bhagwanji Jha and there is a book also on zeolites and their industrial applications.And if you go to these papers, you will realize how the whole process is done.The bug in our mind was that interaction of contaminants with soils is not inert.And many times this interaction might alter the fundamental characteristics of the soilsalso, so this is what actually we wanted to show.Particularly in case of nuclear industry, this type of consents are very useful whereyou are dealing with atomic waste of high toxicity and you know it is a big challengeto dispose of the waste and isolate it from the geoenvironment.So, check the thesises which have been done by Dr. Ravi Linden Rakesh and Dr. Gurumoorthithese are the guys who are sponsored by atomic energy regulatory board of India and BARC.And they have done wonderful work on nuclear waste disposal of you know, from differentatomic power plants and how to isolate them from the environment.Hope you are getting me I do not expect you to remember and learn everything.I am just trying to give the exposure of what is being done and what has been done already.And we are we are heading to that is more important.Is this correct.It is not that you should mug up and remember all this thing this is just maybe a differentdomain of activities of a geotechnical engineering profession.So, in which way the activated ash sample is different property wise first thing inthe minerology, remember this itself is different here you do not have any zeolites in the originalfly ash and once you have activated is you can create the zeolites of your liking.Only thing is you have to just regular the process.So, if agriculture industries have contacting you know what type of zeolites you shouldproduce.Engineering properties, Ya so, engineering properties if you read the paper which iswritten by Dr Kolay in Canadian geotechnical journal 2001.ASTM there we have talked about these type of systems have a tendency to retain waterand they become very fluffy specific gravity decreases because what you are doing is youare digesting silica by using sodium hydroxide all right.So, they become different material which cannot be utilized for load bearing, but it becomesan interesting material or application in environmental issues and leaving a solutionto the environmental problems, cleanup programs.When you have mercury vapors, dioxins, very high concentration of cations.Their take up capacity while more if you put them in the soil, they will not allow anythingto go out of them even if flooding takes place.So, when you construct a dam, the biggest problem is soil become barren.I think we discussed this.The biggest issue is why people are against this construction of dams.It is not only the dislocation of the people the seepage lines What do they do?They take out all the minerals from the soil as an exit gradient.So and water logging downstream.So when water logging occurs efflorescence takes place and all the minerals get washedout from the side sensors become lighter.So, if you want to rejuvenate all these type of things, you should have a metal which ishyperactive old, let things go out easy.There are several applications of this metal in the modern day medicine.I was dealing with some of the business all over the country where they are trying tocreate control drug delivery systems, where these things become the basic component.Most of the diarrheal you know medicines, anti-diarrheal medicines.You use these type of systems where you inject a mineral in your spine which has a very highcapacity soft water.So there are two ways of interpreting the how one is to read and get how it has beendone.Second is answer yourself if you have a question that if tomorrow somebody comes to you tocreate a technology, you take this question as a challenge and give them a solution soin an industry right now want the solution are you realizing this it.

Video 2: Agglomeration of the Ash Particles
This is another example of how is scanning electron microscopy can be utilized to understandthe surface features of the soils.Alright.You have these pictures taken up at different magnifications it is written over here 5000times 10,000 times 15,000 times and what we are trying to show you that the sand whichis supposed to be very passive contains a lot of bacteria on this and as one of theapplications could be in designing the water filters.So if you look at another industrial process, which is known as is a dual flue gas conditioning,DFGC is known as dual fuel gas conditioning.This is normally done to trap the fine particles which are going out of the stacks at the thermalpower plants, you know earlier days these bag filters are not designed or they werenot available in the market.So, bad filters are the ones which are installed at the exit of the chimneys.So, that they will collect dust particles and the dust particles will not get emittedinto the environment.When you say the size of the particle which goes into the environment less than 1 PPM2 PPM then there is a index also which most of the time people talk about when case ofDelhi is discussed, you must be aware of that particulate matter PM index.So at power plants because a lot of fine particles might go into the environment they nowadaysinstalled dust collectors these are bag filters now bag filters material again come back intothe stacks and we will get deposited the chimneys.Now, if you want to sell your fly ashes to different let us say agricultural units.So, what we shown we have shown is that the flash particles which have been collectedby giving a treatment with the flue gas can be utilized as a good fertilizer.And this was a project which was sponsored by one of the consulting groups and one ofmy Ph D scholars Dr. Shantha Kumar worked on this.So, what you are observing here this also answers your questions Shrikanth that.You are trying to grow different types of the deposits on the particles.And what you observe is something which is very deco rational and it has a lot of valuein the ornaments.If you create this type of structure, they shine in night because of their efflorescencethis is all calcium deposits or it could be sodium sulfate which is coming out of thesoils.So, what I am trying to show you here is that depending upon the requirement you can createa solution.So, here the objective was how to create a situation where the fine dust particles whichare going out of the stacks of the thermal power plants can be collected, number 1 withoutbag filters, number 2, whatever gets collected, what to do with that, can this we used asa resource material so the answer was yes this material can be utilized as a good manure.So, we created a sellability for this material sellability in the market.These slides also show the importance of scanning probe microscopy in advance geotechnical andenvironmental geomechanics.Some more examples of how agglomeration of the ash particles can be done in conventionalgeomechanics you use deflocculating agent as sodium hex metaphosphate to deflocculatethe system here I want to create flocs, so that the emissions in the environment reduce.So, now, you can see by injecting ammonia gas, I can create deposition of ammonium sulfateon the particles and this is how the agglomeration looks like.So, they inject ammonia, sometimes they inject sulfur dioxide sometimes they inject carbondioxide sometimes they inject water flumes sometimes in there they describe the particleswith water, a lot of techniques which are being used, I mean, you should realize theyou know, boundary less approach in geotechnical engineering.That is what I always say.All of you have studied this stokes law and suspension you know, depositing in the watercolumn.And my mind is to say that why cannot we do this in a column of flue gas in which theparticles are settling down so this started.Abstract thinking makes your research more interesting.And then you create a requirement in the market by doing R and D and showing to the rest ofthe world that what you are thinking is correct.So most of our projects are like this.Where we create a value out of a material.And then we create a situation where industries get attracted towards research, and they fundthem funders and then this is how the whole system price.You mentioned that you use those fine particles as many of farming does that affect the populationof groundwater.so imagine them the surface area and increased cation exchange capacity has increased incase of extreme desert conditions also you can grow the plants because as I said thesematerial have high affinity towards moisture will not let moisture go out so that meansthrough out the year you can have welting point maintained.Which plants can use to survive themselves?So, this was a very revolutionary thinking otherwise sands alone cannot sustain the plantsin extreme climatic conditions in deserts.And then comes Of course, first thing is creating a material and then mechanics of this materialsuppose if I have to create a filter bed out of this.As she was asking, we wanted to do some experiments to show how plants growth can be controlledby using this type of concepts.I mean, you will be surprised to know that all these type of systems that are very muchuseful for poultries, where you have a lot of foul smell in poultry and aquaculture andfish culture, these things are becoming a pool because they have a tendency to solvefoul gases H2S particularly as the you know, animals and birds do not fall sick so thereare a lot of applications.