Help me in pump sizing for cooling tower water circulation 2

[Asisraja D]

Hello professionals
I am working as a project engineer in a chemical company. We are starting a new project with small pilot plant construction and I will list out the equipments & condensers here. The question is as a project engineer I have got less details from our process engineering group so i want your help to design a pump based on the details I have in my hands so please bear me in this.

Overall reactors :
Reactor MS/SS316 : 1.0 KL - 1 No's (Jacket volume 200 Liters)
Reactor GLR : 1.0 KL - 1 No's (Jacket volume 200 Liters)
Reactor MS/GLR/GMP : 630 L - 1 No's (Jacket volume 160 Liters)
Reactor MS/GLR/GMP : 630 L - 1 No's (Jacket volume 160 Liters)
Reactor SS304/SS316/GMP: 600 L - 1 No's (Jacket volume unknown)
Reactor MS/GLR/GMP : 250 L - 1 No's (Jacket volume unknown)


Overall condensers :
1. SS316 - 4 Sq.Mtr - 2 No's (Box type)(Overall Tube volume for both 24.64 Liters)
2. SS316 - 8 Sq.Mtr - 2 No's (Box type) (Overall tube volume for both 47.52 Liters)
3. Graphite condenser - 6 Sq.Mtr - 3 No's (Block type & utility volume unknown)
4. Graphite condenser - 8 Sq.Mtr - 1 No's (Block type & utility volume unknown)

Cooling towers (150 TR) - 2 No's
Cooling tower-1 for only reactors & condensers
Cooling tower-2 for 20 TR (-10 Deg.C) Brine chiller's condenser cooling purposes.

Header routing is like "L" Shape so consider
length 1 - 21 Meters & Length 2 - 12 meters.

So i have to design two pumps for two cooling towers based on the above details.

sorry for editing the question because it took hard to collect the data from our process team. i will update my planned PFD (Process flow diagram) Soon.

Thanks in advance.

 

[Rputvin]

Each of those pieces of equipment should have a manufacturer rating for required heat removal, including flowrate and temperature requirements.

You need to build up a system diagram, decide on a nominal flowrate based on the equipment requirements, and then match the pump head to the expected system head at the desired flowrate.

And if your cooling tower is an open-evaporative style, I would very much recommend against pumping that water directly into your equipment. Open towers generate a large amount of dirt, biological growth, and scale, and will need filtration, and may need aggressive chemical treatment to stay in check. If your tower is a closed-circuit evaporative style where there is a water coil inside of the evaporative tower then you've isolated the open water from the closed-loop equipment water already.

 

[Asisraja D]

Rptuvin sir
This is evaporative cooling induced draft tower & there is open loop model.

 

[LittleInch]

You won't get anywhere without heat rejection load and a design for your cooling system.

You could be a factor of 10 out either way if you guess this.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Asisraja D]

LittleInch sir
You are talking about heat load of each individual equipment.

 

[LittleInch]

Yes.


Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Asisraja D]

LittleInch sir
Can i get any calculation part with any example heat load from your side? It would be helpful for me when I get those details.

 

[1503-44]

You seem to be a long way from selecting a pump for this.
Start this exercise only after your process engineer gives you a flow rate.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Asisraja D]

1503-44 Sir
Sorry for poor details, kindly review my question again that i have modified with more details.

 

[1503-44]

Unfortunately you are collecting the wrong data to solve this pump problem.

Pump selection requires flow rate, or a range of flow rates showing the minimum and maximum water flow (m3/hr)

And head loss (m) or its equivalent pressure loss in bars.
You may be able to determine that, if you know the flow rate and geometric details of the pipe system.

If you do not know the flow rate, you really have nothing.
Please see your process engineer again. This time ask for flow rates.



--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Asisraja D]

15033-44 sir
So i will have to collect the flow rate details from process engineers for each equipment.

 

[1503-44]

Yes. And how they all should connect to the cooling water. Parallel, series, etc.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Asisraja D]

1503-44 sir
yes.And how they all should connect to the cooling water. Parallel, series, etc.

I have attached the conceptual layout for the piping with the pump.

"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[1503-44]

You can paste directly if you use jpg image format. Do not use pdf for images.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Asisraja D]

1503-44 sir
Please see your process engineer again. This time ask for flow rates.

process engineers are our Managing director & My reporting manager they both have experience in this industry around 15 to 20 years so they simply select the pump based on their experience using Q=AXV formula and head loss for each 10 Meters = 1 Bar. That's it and they judge their decisions because of marketing and investment strategies. for example if i design my plant for a particular process for a particular product if suppose if that product consumption decreases in the market then again we will have to go for a next one so to avoid this they think like to provide common headers & flow rate based on the thumb rules. that's it sir.

"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[shvet]

10 Meters = 1 Bar

1000 meters = 1 bar?

 

[Asisraja D]

shvet sir
10 Meters = 1 Bar = 14.7 PSI. This is for loss of head due to height of the building. If we have 15 meter building height and so then we simply decide with 25 meter head for that pump because it 25 meters = 2.5 bar so 2.5-1.5= 1 bar line pressure we can get.

"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[LittleInch]

Then you need to ask them what their ROT is.

Maybe it's jacket volume turned over every minute?

But as I said you could be out by a factor of 10.

It seems a very loose way to design and build a plant....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Asisraja D]

LittleInch sir
Then you need to ask them what their ROT is. means (Reactor outlet temperature) ?


"Strive for perfection in everything you do. Take the best that exists and make it better. When it does not exist, design it." - Sir Henry Royce

 

[LittleInch]

That as well but its also an abbreviation for Rule OF Thumb, i.e. an educated guess.

Your inlet to outlet temp of your cooling tower is probably no more than 10 C and possibly less.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.