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0:14
What's up guys, it's time to start our course in reactor engineering We are now in block number one, which is essentially chapter one on your book fogglers book of remember it's basic elements of chemical reaction engineering and Yeah, we're going to see Introduction and the molar balances We're going to explain of course what's a molar balance, how to do it, how to apply it to a reactor and essentially we're going to find out some equations or design equations for those reactors.
0:51
So this video it's essentially section number one, we're going to see the introduction to reactors, what type of reactor do we have, some reactor kinetics and the uses of those reactors. Then we're going to see a lot of pictures I'm going to try to explain you how to recognize or to know what's a reactor in the chemical industry and in the second video We're going to jump to molar balances, which are done essentially in batch reactor, continuous stirred tank reactor
1:23
Plug-flow reactor and packed-bed reactor. Right now we're going to see just the introduction introduction to reactors
1:34
So the first thing I want to let you know is what's a reactor? A reactor is I try to look out for many many definitions but I think the most common sense definition is this one, it's an equipment used to carry on a chemical reaction. So essentially if you have a mixing unit and you are not doing a chemical reaction that's not a reactor but if you are carrying on I you are doing a chemical reaction therefore that's a reactor and actually
2:07
there's also types of pipe if you're using this pipe just to transport material and you don't know you're transforming A to B technically speaking this is a reactor of course we don't want to do that we want this pipe to transport A into of course on the A we don't want transformations but technically speaking if you have something a device or equipment that transforms a chemical reaction then you have a reactor so yes chemical
2:39
engineers design reactors to maximize net present value for the given reaction so that's kind of fancy what does that mean is essentially you want to improve the reaction in order to get more profit so let's keep doing how do we do that? The designers which looks like a fashion design but now it's not fashion it's engineering design or reactor design ensure that they got the highest efficiency possible towards the desired product so you're turning A
3:14
into B of course you want to turn all A into B. Sometimes you're not going to be to be able to do that so you're going to find out or design a reactor or try to change temperature, pressures, flows, whatever you need to do to improve that conversion rate and actually you're going to base all these in money so of course if I tell you I'm going to increase 1% yield but you're going to need to invest 1 million dollars well you need to check out if it's actually
3:49
worth that 1% so yeah that's the highest yield of product and as I told you before you need to require the least amount of money to first of all purchase or to invest and to operate because one thing is having the reactor the other thing is actually operating you will need someone there taking care someone that cleans, someone that operates control temperature, heating cooling, piping, pumping, compression, all those stuff that are behind the
4:24
operation. So why do we need reactors? Well we want to convert material that's what I love chemical engineering it's about transforming converting producing materials which are not that useful or which maybe they are useful but you want to turn them into something else. So let's say you have this low-value material and I love it because you use your knowledge your brain and you transform it into more profitable material so that's why I love chemical
4:59
engineer let's do some magic with our knowledge and we get more money with that we do it because we want to have a specific unit for that operation so at least we know that this tank is where our chemical reaction is taking place so if you don't have in the let's imagine this plant or chemical plant you have a problem you're not getting the jilt or the conversion you want you go to the reactor you study the reactor here you don't need to check this out or this out
5:32
or this piping here maybe eventually if you find out that the reactor is fine you will need to do that but the first thing you want to do is to go directly to the reactor so that's why we are doing this in one reactor and not in many operation units so yes essentially you want a specific point or space where the reaction is being carried and not only that you also want the reactor to control the reaction in a safe manner so you don't even know where your reaction
6:05
is taking place well that's not that safe you know you're taking place in place in the plant or at least that it doesn't explode or leak or whatever stuff or thing may happen that may be hazardous for health or environment or workers whatever and the thing here is that it's easy to maximize efficiency why because then you're going to work fully on this reactor and not in the whole plant so you can I don't know change the volume change temperature of flows
6:45
pressure flows, concentration, all those process variables that affect the conversion rate or yield, you can change them. So that's kind of cool because you're going to change also levels, temperatures, inlet, all those things that you can change, you're going to do them in this specific unit. So the next thing we're going to see is the types of reactors there are many let's say types of reactor or how to order them or classify them so I brought you the most
7:22
common and the ones you're going to be using for example batch or you can say also is that semi batch process or a continuous process this is in general you have a plant operating all the day all the year long you transform A to B let's say in this reactor and you have a flow of 10 kilograms per hour here and you take out 10 kilograms per hour of B this is A it's an example a batch is essentially just you got this tank you fill it up you let time pass it reacts
7:57
and you take it out a semi batch is a mixture between a batch and a continuous that's one one another type of reactor classification is either is it catalytic or not catalytic when it's catalytic of course the name implies you have a catalytic, catalytic Sater or catalyst and when you do not have it well it's a non-catalytic reaction then homogeneous reactor which means they are the same phases let's say liquid-liquid or solid with solids and then you have the heterogeneous phase
8:33
for example when you have this say you have a gas here and this is like a packaging you need this solid so they react or they do a process here and they interact between solid and gas which is a heterogeneous reaction and yeah you take out these here out so that's also important and the most I think the most important thing to know is these categories which is the reactors we're going to be starting in this course this introduction to chemical engineering reactors so the
9:16
batch reactor is the most classic and obvious one then comes the semi-continued reactor which I told you is a part batch and part continuous then we go to a continuous stirred tank reactor which is the most I think basic and easy to model one you have a tank and as the name says it's continuous so you have this flow and this flow and you mix mix mix and react and take out the product so as you can see is a tank which is stirred continuously and it makes
9:50
reactions. Then comes the plug flow reactor which is essentially some pipelines here you are reacting the material in the pipes so you got A and it start reacting all over here and you get out B and then the packed bed reactor which I told you this little example you have this reactor you got this packed bed here and you are reacting I don't know gas with the solid and you take out the product. So those are the type of reactors, please. This is
10:20
kind of theoretical. I know it because I've done too much of that. I actually didn't like memorize it. You don't need to memorize it. You're going to be working with them and you're going to see the characteristic of each of them. For example, continuous or in steady state, heterogeneous normally implies a packed bed here batch reactor it means that they're time-dependent and with the time you're going to recognize each of these concepts and now I brought you
10:51
some pictures I want you to realize what's a reactor look this tank you can see this is like the over part and this will be the whole tank this is an inlet maybe and this outlet here or maybe this is the inlet and this is a level then you got this part here which is the where the agitation unit goes so you have this unit here it goes all the way down of course this this should be 90 degrees this is let's say laying down so you need to stand
11:28
this tank up and you will have this your agitation unit here and you're going to mix it
11:35
And this as you can see is a tank and you have this the steering system here So as you can see is a continuous stirred tank reactor reactor because you have the inlet here and maybe outlet I Don't see the outlet, but you should be there and this is the manhole What's a manhole is essentially a place in which a man can go in and you clean it or you can check if there's something Stuck or something like that
12:01
Then we have still I see
12:05
SDR or a continuous stirred tank reactor you can see here is the thing we were talking about and this is the steering unit but we got this now a jacket system what's a jacket system we're going to see that later but essentially is just a lot of tubes that are heating this reactor you can see you have many inlets here made for levels temperature sensors and the mouth now we are in a plug flow reactor as I told you before is essentially just pipelines they go
12:36
here go higher and as they move they are reacting the materials so eventually if you were having A plus B here and your reaction is something like this well you're taking out C out here the same here now we have a different arrangement and you actually cover this so maybe it's more like aesthetic maybe you're selling the reactors you want to do it as aesthetic as possible but actually in the chemical industry you're not looking that into aesthetics you are more into
13:14
usefulness efficiency and that and makes sense because if I were an engineer I wouldn't care it is not fashion at all but if it works it turns my material A into B and I can sell B way much expensive I will not care about the fashion elements and then we have a packed bed reactor it's essentially the same tank this is the diagram because if I give you the photo you will not be able to see the packaging of course because this will be cover of all
13:47
metal walls you have the reactants you take them here maybe this is gas and And this is a catalyst, you have the catalyst on this bed or this solid part, so they react, they make their reactions and you take out the products. It's not that difficult or complex as it seems, it's so easy.
14:11
Then yeah, still we are talking about packed bed reactors, as I told you before, you can see there's nothing, it's only metal, you can see the packed bed.
14:21
so you could have different arrangements of pellets, pellets are these balls or these catalyst, these contain the catalyst so you could either have a slick or slim here you can have a wider you have many small pellets or big pellets and obviously it depends on what are your requirements on pressure drop you want to increase conversion to increase the surface area there are many many things that you might want to consider it's not just about okay just
14:53
pull them out here. So we're now in these subcategories which are the lab reactors or reactors that are done on lab scale you can see they are simply you've been in a chemical or a chemistry lab you can recognize this is like a small beaker you have all the supports you've got this little condenser which has nothing to do with the industrial condenser and yeah all you have all this electric control device the you got this constant pressure funnel all these
15:29
discharge level of course you have an inlet and as you can see this is done to improve the reaction so if you can improve them in the lab you can improve them maybe at the larger scale so the same here normally you use chemistry
15:47
workers or chemists or even also chemical engineers to improve the reaction. The thing here is that you want to improve the yield or maybe you want to lower a temperature or heat requirements or viscosity so you get lower pumping cost. All these things that might interest you are here and normally you also want to model that so you can model the lab one or the lab experiment you can see how I don't know many transfer materials maybe this is
16:21
momentum transport this can be a heat and heat transfer or not this actually let me say this is a heat or temperature profiles these are momentum or velocity profiles you can see all the agitation here and maybe this is the mass profile how they're changing this let's say the blue one is A and the red one is B and A is turning into B so you can see how at the beginning you have a lot of A and D at the end you have a lot of B which makes sense because you're transforming
16:56
A into B so that's why you can also get some lab reactors you want to improve and model and eventually just get a better version of your real reactor in the in the chemical industry. Same thing here you can recognize them maybe this is a CSTR small scale and this is a PBR of course you have this packed bed as you can see you have a lot of spellets so I am guessing these are bed a packed bed in which you get here the gas and you take the outlet. So yeah same
17:38
thing here you have actually this is also a packed bed reactor but you cannot see the packaging only here but you need to be watching closely and yeah essentially that's lab reactors we're going to see a new trend which is micro-reactors. Essentially the name says micro then to minus 6 meters
18:01
So why do we use this because we get many at the micro scale we get many many good things you can control better essentially it's all about transport phenomena hopefully you've seen that before because you're going to get that you get laminar flow and you get more pressure control and heat controls and all that stuff and yeah you can see another here you have You got a better control of the reactants and the thing here is once you got this microreactor working as you wish
18:37
You can get I don't know maybe 10 to the 6 units, which is about 1 million or maybe you just want 1,000 and Depending on the flow of course and your requirements, but you can get this very scale up with the scale up abilities so the same thing here this instead of using piping you got these hoses small hoses here instead of getting huge pumps you got small pumps and yeah that's the micro reactor trend now just to let you know about thermal insulation you've
19:15
seen this in heat energy or mass balance maybe heat transport operations whatever but I'm going to explain you once again just to let you know so these spots right here this is a with the thermal camera all these as you can see if it's yellow it's hot or let's say it's a high temperature and if it's black it's low temperature so what you want to do is low temperatures because the ambient temperature will be around 25 Celsius or think 75 it's about like
19:54
that so you don't want high temperature because high temperatures implies there's a difference in temperature and difference in temperature means that you're going to lose heat with the ambient temperature or the ambient air so you don't want that you want to avoid all these little points here and how do you do that you do it by insulating or generally insulating the reactor so look get this instead of losing all the heat you just cover the reactor cover the
20:26
inlets or all the piping and you get this kind of arrangement so look for this you have all these pipes are covered this is not metal this is insulating material and you also cover the heating vessel what type of material used they use a lot but this is how they look it's like a foam leg or like as best like you also use you cover it with aluminum and yeah essentially that's the thermal insulation one thing I want to I want you to let you know is let me
21:03
go to the next picture I remember going to my first chemical industry and I thought these were pipes and I wasn't that bad because they're actually pipes inside of it but I thought these were the whole pipes and that's not true actually you got this isolation inside this metal so you see the pipe here it's actually covering the insulation material so maybe the actual size of this pipe will be I don't know this size so even though you see a huge pipe or a huge
21:38
tube here you got this small tube here because it's super hot and you got around it all these material so that's about thermal insulation just a overview so you can know like there's insulating problems in reactor so if you want to keep a temperature for example you want to be at the same temperature is a thermical you will need to take care about that or if simply you don't want to expend that much money in heat requirement you will need to buy some
22:12
insulation material and that's everything for this chapter this section section number one let me tell you what we've seen so far we saw a small introduction to reactors, type of reactors, reactor that takes you the uses of these reactors and well this is I just move it to here what's left is section two molar balances of batch reactor, continuous stirred tank reactors, plug flow reactors packed bed reactors we're going to see now the mathematics and we're
22:43
going to derive an equation that help us to model these four reactors so thank you for watching guys if you are interested in how we can model these tanks or these reactors, please just go to the next video.
23:00
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23:57
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24:16
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