pumps for loading and unloading inside the tankfarm 3

[europipe]

Dear collegues, someone proposed to locate pumps for loading and unloading inside the tankfarm,
Personally I'm not enthusiastic, because of hazard and maintenance issues.
Like to know what my respected collegues here think about this idea,
NPSH becomes better, but one can select pumps that are sufficient.

 

[EmmanuelTop]

With proper ATEX classification, you can place the pump anywhere you want.

http://antwrp.gsfc.nasa.gov/apod/astropix.html

 

[pennpiper]

It depends on your definition of "inside the tank farm,"

Does this mean:
(a). inside the Dike (Berm) with the Tank?
or
(b). outside the Dike but in the same are general area as the Tank?

Issue number 2 is the commodity. What is the commodity?

prognosis: Lead or Lag

 

[europipe]

Mr Penn,
Proposal is (a/b)inside the concrete walls near the tanks (~10m dia 12m high)
Products are mostly flammable.

 

[pennpiper]

Euro,
Pumps inside the concrete wall with flammable product is a very bad idea.
Reason:
- Flammable products (aka Hydrocarbon) tend to give off vapors. The vapors of many hydrocarbon products are heavier than air so they will pool inside the walls. If there is a spark it can explode. If the walls are 2 meters high (higher than a man), you have a swimming pool filled with a lethal mixture that can overcome and kill any worker who enters the area to perform operations or maintenance.

- What can cause a spark? You have a piece of mechanical equipment (a pump) no doubt driven by and electric motor. Ask your Safety department how many ways this pump can cause a spark.

- What do the local Codes say about this arrangement? In the USA we use the NFPA (National Fire Prevention Association) Codes. I do not currently have access to a copy but if I remember correctly the one governing this issue ruled the pumps shall be located outside the secondary containment.
(Ref: NFPA 30 Flammable and Combustible Liquids Code)

prognosis: Lead or Lag

 

[europipe]

Mr. Pennock, the idea came from our USA collegues, I agree with all your arguments.
(Thought it was a Anglosaxon idea), with your input I'll try to convince them.
Thank You.

 

[LittleInch]

Whilst it is not normal, the risks by pennpiper, IMHO, are a little exaggerated. Yes, vapour can gather, but to get to an explosive amount you actually need a lot of vapour. If that much is escaping from your tank, you've got big problems as the bund won't keep it in. It would probably be a zone 1 area and maintenance is more difficult as you need gas tests and access for equipment limited.

However so long as the equipment is suitably rated for use in explosive atmospheres you can put it there. There are many electric actuators on tank shells and other similar equipment.

NFPA30,I can't say, but could be your key point.

It is usual to place them outside the bund alright, but if you have something that needs a pump there then it can be done safely.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[BigInch]

I must say that I have NEVER seen NONsubmersible pumps inside the diked area of a tank. Not that I haven't seen some guys try to do it. They just don't often succeed. What happens when a tank fails and floods the pump? If you were going to do that, why not get some submersible pumps and put them inside the tank itself. If your tank is leaking, wouldn't you want to run the pumps to move the product out of there? Not convenient if the pump is flooded with gasoline, or even water. Especially inconvenient if it was lightning that struck the tank and happened to cause the leak and set the inflamable product on fire.


I hate Windows 8!!!!

 

[chicopee]

I would place the pump house outside the dike as it would be easier to repair and replace pumps and valves. Bear in mind the integrity of the dike if the piping is to go through it.