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Pump Efficiency 3
- Thread starter youssouf
- Start date
LittleInch
Petroleum
Exploitable??
Waste water pumps are often open impellors to avoid clogging and can be pretty inefficient.
Not much to go here....
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Waste water pumps are often open impellors to avoid clogging and can be pretty inefficient.
Not much to go here....
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Ummmmm.... word usage issue here ?
"Exploitable" can mean "easily fooled" as well as many other things ...
Can you tell us what you are trying to do ??
MJCronin
Sr. Process Engineer
"Exploitable" can mean "easily fooled" as well as many other things ...
Can you tell us what you are trying to do ??
MJCronin
Sr. Process Engineer
- Thread starter
- #7
Hi
It's 40 HP with open impeller to transfer wastewater from a sewage lift station to another (2500 meters).
My question was: Using a pump with 32% efficiency for this operation (Is it the optimum choice ?) if NO, What should I do (Changing pump type ?.....)
Mr. MJCronin : I'm sorry for my broken English.
It's 40 HP with open impeller to transfer wastewater from a sewage lift station to another (2500 meters).
My question was: Using a pump with 32% efficiency for this operation (Is it the optimum choice ?) if NO, What should I do (Changing pump type ?.....)
Mr. MJCronin : I'm sorry for my broken English.
LittleInch
Petroleum
First you need to create a pump data sheet with required duty point with head and flow and then send it to different pump suppliers.
Then if this duty is continuous or operates a lot then start to look at the efficiency of the pump and calculate the OPEX costs and not look just at the price.
Is your pump operating at its best efficiency point? Is it too big or too small?
Have you got the pump curve? And the process conditions?(flow, head)
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Then if this duty is continuous or operates a lot then start to look at the efficiency of the pump and calculate the OPEX costs and not look just at the price.
Is your pump operating at its best efficiency point? Is it too big or too small?
Have you got the pump curve? And the process conditions?(flow, head)
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
- Thread starter
- #9
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1
- #10
LittleInch
Petroleum
yousseff,
You need to put out all the information you have and not just drip feed information. How was I supposed to know that?
Then it's part of your evaluation. Look at power consumed over say a 5 year period and then include the CAPEX cost for different options.
Often a vendor will give you the best choice he has available. Which may not be the best available in the market.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
You need to put out all the information you have and not just drip feed information. How was I supposed to know that?
Then it's part of your evaluation. Look at power consumed over say a 5 year period and then include the CAPEX cost for different options.
Often a vendor will give you the best choice he has available. Which may not be the best available in the market.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
- Thread starter
- #11
Hi Youssouf,
I agree with all the comments above. I just want to remind you that you may need a much bigger Capex if you need a spare pump installed to guarantee the operation 24/7.
Make it clear with the operation and maintenance teams.
Normal practice is to get several quotes from different suppliers (at least 2) to make a comparison.
My 2 cents
Pierre
I agree with all the comments above. I just want to remind you that you may need a much bigger Capex if you need a spare pump installed to guarantee the operation 24/7.
Make it clear with the operation and maintenance teams.
Normal practice is to get several quotes from different suppliers (at least 2) to make a comparison.
My 2 cents
Pierre
georgeverghese
Chemical
Since this is a wet pit type pump, guess you'll need to take a good look at the shaft seals. What alarms are provided for seal failure?
Also check and compare materials of construction, % excess power available.
Also check and compare materials of construction, % excess power available.
As usual too much info way-off from the original question of why low efficiency. Without a lot more detail from the OP it's all wheel spin.
To youssouf, how about posting the data you you sent to the pump supplier so that those of use who know how to select pumps can make some sense of your question.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
To youssouf, how about posting the data you you sent to the pump supplier so that those of use who know how to select pumps can make some sense of your question.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
- Thread starter
- #16
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1
- #17
- Thread starter
- #18
youssouf
Without a good search of the internet and not having any pump curves available, I think finding a pump rated at 18m3h @ 79 metre head pumping waste water with a decent efficiency will probably be impossible. As it is pumping waste water it should be running at maximum 4 pole speed - this will mean a large pump running well to the left of the curve at very low efficiency.
Can you post the pump selection you have showing the 32% .
PS. Changed possible to impossible (typo error)
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
Without a good search of the internet and not having any pump curves available, I think finding a pump rated at 18m3h @ 79 metre head pumping waste water with a decent efficiency will probably be impossible. As it is pumping waste water it should be running at maximum 4 pole speed - this will mean a large pump running well to the left of the curve at very low efficiency.
Can you post the pump selection you have showing the 32% .
PS. Changed possible to impossible (typo error)
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
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- #20
georgeverghese
Chemical
At the OpCo I used to work at, there were problems with swelling and chemical degradation of the rubber sheath for the water wetted section of the electrical power supply cable - caused by incompatibility of this rubber with traces of petroleum in the caisson. If your waste water is acidic, check this sheath and cable gland materials also.
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