00:01My friends welcome to our channel. Today we are going to understand how to design a vessel or a drum.
00:08So let's start.
00:10What is a vessel or a surge drum?
00:13Basically vessel is a piece of equipment which stored the liquid or a fluid for a particular time or for
00:20a particular time which is called residence time.
00:23And which will give you a sufficient time to take a corrective action in case of upset.
00:28So vessel basically understood by what application it is.
00:32It used to absorb the variation incoming fluid provide the uniform feed.
00:37Suppose you have receiving feeds from the three different units like this and you are pumping it to the other
00:44unit.
00:44So if this pump gets stripped this upstream unit will get affected if this you do not have this drum
00:51or a vessel.
00:53Because it is directly connected to pump or some header and you do not have any residence time.
00:59And suppose this upstream unit gets stopped because of some reason your pump will get problem.
01:05It will not get a sufficient suction because you do not have any drum.
01:10So drum or a surge vessel is used for that purpose.
01:13That is the basic use of the vessel.
01:17Vessel also used for a separation.
01:21So that two phase three phase separation vessels are used.
01:24But that also needs some residence time.
01:27From fluid in to fluid go out.
01:30And we understood the terminal velocity and that part.
01:33So that will be also done in the vessel.
01:38So vessel sizing is the first step in separator sizing as well.
01:44So before starting the separator sizing we should understand the vessel sizing.
01:49So this vessel also have the application of allowing the time to problem correction and absorb the temporary increase.
01:57So basically vessel should be designed for the residence time.
02:02That is to correct the upset condition and maintain level.
02:06So residence time shall be calculated based on the maintain level of the vessel.
02:13Whatever the timing you are calculating residence time.
02:16If you are saying I have 15 minutes of residence time in this vessel.
02:19Which will be based on the what level you want to maintain.
02:22It is not on the complete diameter of the vessel.
02:25Or you can say complete die of the vessel.
02:27It should be based on some level.
02:30That you have to fix.
02:32And based on that you have to calculate the diameter.
02:37So these are some typical residence time guidelines for the vessel.
02:42So vessel if it is a feed drum which is feeding to some unit.
02:45That is residence time will be 10 to 20 minutes.
02:48Reflex drum of any distillation column or any column.
02:52Which will be around 5 to 10 minutes.
02:54Surge drum is to the furnace.
02:56It will be 10 to 15 minutes.
02:58Intermediate storage between the two units.
03:00It may be also between 15 to 30 minutes.
03:03And the product drums going to the storage.
03:06It may be 5 to 10 minutes.
03:07These are for the vessels not for the separator.
03:10Separators have their different residence time.
03:14Based on the viscosities and other of the lighter on the heavier particles.
03:20So how to size a vessel.
03:23So vessel has to size based on its application.
03:26You have to select the residence time.
03:27So that is the first key.
03:28We have to find out what is the residence time based on the application.
03:32Then what level you want to maintain.
03:34Normal liquid level.
03:36High high liquid level.
03:36Or low low liquid level in your vessel.
03:39Based on that you can size your vessel.
03:41We will see with some example.
03:43And the vessel sizing is the first step in separator sizing.
03:46So before going on to the separator sizing.
03:49We should understand the vessel sizing.
03:51So we will understand with one problem.
03:54Suppose we have a flow rate requirement of 50 meter cube.
03:57With a residence time of 30 minute.
04:00And 70 percent liquid full.
04:02So these two points we already received.
04:04In this problem statement.
04:06And the flow rate.
04:07So we will see.
04:08So suppose this is a vessel.
04:10Which will have a flow rate of 50 meter cube inlet flow rate.
04:13And it is going somewhere in the downstream.
04:16With a half an hour of residence time.
04:20With level is always filled.
04:22And this volume of this vessel.
04:26Or residence time is between this 70 percent level.
04:29To the bottom of the tank.
04:32And this is the alleged space available.
04:34For the additional fluctuation to take care.
04:37So for the solution.
04:39We will select first the L by D.
04:40L by D ratio generally is.
04:423 for the vessels.
04:45So based on L.
04:46Then first step.
04:47We have to calculate the holdup volume.
04:49Which is flow into time.
04:51So it is Q into 0.5.
04:54That is a half an hour.
04:56Which comes the.
04:57Holdup volume comes the 25 meter cube.
04:59And the volume of the vessel.
05:01We can calculate based on the.
05:04The holdup volume.
05:06By how much level you require.
05:08If it is 50 percent.
05:09You have to divide by 50.
05:10If it is 100 percent level.
05:12You design for the 100 percent level.
05:14Then just.
05:14It will be 25.
05:16But 25 by 0.7.
05:17Because of the 70 percent level.
05:18It comes.
05:2035.715 meter cube.
05:22So this is the.
05:23Your.
05:23Volume of the vessel.
05:26So we got the volume of the vessel.
05:28Based on the.
05:30Residence time.
05:31And the.
05:32So based on that.
05:34And we have the.
05:35L by D as.
05:353.
05:36So from.
05:37For that.
05:38Then we will solve for the.
05:39Calculate the diameter.
05:40Or the D.
05:41So volume of the vessel is.
05:43Pi D square by 4.
05:44Into L.
05:45If you substitute.
05:47That is.
05:47L is equal to.
05:483D.
05:49In this equation.
05:51Then.
05:51You will get.
05:533 pi D cube.
05:54By 4.
05:56V total.
05:57And V total.
05:58Is the holdup volume.
05:59So holdup volume is.
06:0035.715 meter cube.
06:04And when you solve it for the D.
06:07You have to put your.
06:09Volume of the vessel here.
06:11Then you will get.
06:11The D as.
06:122.
06:13475 meter.
06:15And based on.
06:16L by D.
06:16You can get.
06:17Length of.
06:177.43 meter.
06:19So you can.
06:19Round up it to the.
06:21Next.
06:22One that is.
06:232.
06:23You have to.
06:24Round up it.
06:24200 mm.
06:26Every time.
06:26You should not be.
06:27Between 57 mm.
06:29Or something.
06:29It should be.
06:30Round up it.
06:30200 mm.
06:31Or the 6 inches.
06:32If you are doing.
06:33In the inches.
06:35So this way.
06:36We can calculate.
06:37The.
06:40Based on.
06:41On this.
06:42Vessel sizing.
06:43While doing.
06:45Three phase separation.
06:46We can get.
06:47Based on this.
06:48Diameter and.
06:49The.
06:49High liquid level.
06:51We can.
06:52Calculate the.
06:53Continuous phase velocity.
06:55And as you know.
06:56For the separation.
06:57Your continuous phase velocity.
06:59Should be.
06:59Lower than your.
07:00Terminal velocity.
07:01So this.
07:02Section is used.
07:03When we have to.
07:04Calculate the.
07:05Liquid level.
07:06And the diameter.
07:06Comes in.
07:07Picture.
07:07When we have to.
07:08Calculate the.
07:09Continuous phase velocity.
07:12Also.
07:12To.
07:13Get the.
07:13Final volume.
07:14You should.
07:14Have to.
07:15Add.
07:15The.
07:15Two heads.
07:17For the.
07:18Vessel.
07:18That will be.
07:19The.
07:19Your.
07:19Total volume.
07:20Will be.
07:21Additional little bit.
07:22But that is.
07:23Not.
07:23Required to.
07:24Calculate.
07:24During this.
07:25Calculation.
07:25It is.
07:26The.
07:26Final volume.
07:27When you want.
07:27To calculate.
07:28Take this.
07:29Two heads also.
07:36Very much.
07:36If you have.
07:37Any question.
07:38You can.
07:39Write to us.
07:39Or comment.
07:40On.
07:40The comment.
07:41Box.
07:41Or you can.
07:42Also.
07:42Reach on.
07:43To us.
07:43Concept.
07:442025.
07:45Gmail.
07:45Com.
07:47Link of.
07:48The sessions.
07:49All the.
07:49Sessions.
07:50We.
07:50Completed.
07:51It is.
07:51Model 1.
07:52Pressure.
07:52Relief.
07:53Model 2.
07:53Heat.
07:54Exchangers.
07:54And Model 3.
07:55Separators.
07:55Are going.
07:56On.
07:56So.
07:56For.
07:57All.
07:57This.
07:58Available.
07:59In.
07:59Description.
07:59Most.
08:00You.
08:00Go.
08:01Through.
08:01It.
08:02You.
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