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Truck offload pump 4
- Thread starter dru8923
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DesignerMike
Mechanical
Are you looking for a gas powered pump then?
Many tanker trailers have offload pumps build in (but apparently not this one?)
How fast do you want it off loaded?
How large is the storage tank (height to determine head requirements)
What type of pump are you looking for? (there are probably 10 different type of pumps available)
I would GUESS your cheapest option would be a small gas powered centrifugal (if the viscosity is low)...but I'm not very experienced with NAOH.
Many tanker trailers have offload pumps build in (but apparently not this one?)
How fast do you want it off loaded?
How large is the storage tank (height to determine head requirements)
What type of pump are you looking for? (there are probably 10 different type of pumps available)
I would GUESS your cheapest option would be a small gas powered centrifugal (if the viscosity is low)...but I'm not very experienced with NAOH.
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dru8923,
Can you order the NaOH in a truck that comes with it's own off-loading pump?
Can you order the NaOH in a truck that can be pressure off-loaded?
Your purchasing folks should be able to look into these options for you.
Good luck,
Latexman
Can you order the NaOH in a truck that comes with it's own off-loading pump?
Can you order the NaOH in a truck that can be pressure off-loaded?
Your purchasing folks should be able to look into these options for you.
Good luck,
Latexman
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We currently bring in a truck 1-2 times each day, to keep our tank level between 17-20 times per day. I have called several suppliers and they tell me they only store caustic, they do not provide trucks. I did contact one caustic trucking company and he told me they have a 5000gal truck with an offload pump which offloads in approx. 2 hours.
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Montemayor
Chemical
dru8923:
Offloading 8,000 gallons into a storage tank should be a piece of cake for a normal, nominal 150 gpm truck-mounted pump. The operation should take less than an hour - which is the time period I would design around if I were pumping caustic. As no coincidence, I believe you'll find that an offloading rate of 150 gpm is just about what most chemical process plants and transporters operate on.
Do not rely or specify on the time quoted to offload the caustic. The measuring stick normally used is the maximum pumping flow rate allowed to you by your company's guidelines or the transporter's operational standards. When handling or transferring hazardous substances such as caustic it is considered smart and safety-wise to not decrease the transfer any shorter than a pre-determined, empirical figure in order to ensure that sufficient time is allowed to react or prepare for an eventuality or process upset during the actual transfer. I've normally used an hour as the minimum time to transfer a fluid such as caustic; other engineers may opt to use less time.
I hope this experience is of some help.
Offloading 8,000 gallons into a storage tank should be a piece of cake for a normal, nominal 150 gpm truck-mounted pump. The operation should take less than an hour - which is the time period I would design around if I were pumping caustic. As no coincidence, I believe you'll find that an offloading rate of 150 gpm is just about what most chemical process plants and transporters operate on.
Do not rely or specify on the time quoted to offload the caustic. The measuring stick normally used is the maximum pumping flow rate allowed to you by your company's guidelines or the transporter's operational standards. When handling or transferring hazardous substances such as caustic it is considered smart and safety-wise to not decrease the transfer any shorter than a pre-determined, empirical figure in order to ensure that sufficient time is allowed to react or prepare for an eventuality or process upset during the actual transfer. I've normally used an hour as the minimum time to transfer a fluid such as caustic; other engineers may opt to use less time.
I hope this experience is of some help.
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Most of our truck unloading pump are traditional motor driven centrifugal pumps. Some are sealed but many are mag-drive. In a few cases, we use air powered diaphragm pumps. The largest pump made by Wilden (I think it was an M-15) worked well in one waste water application. I prefer a motor driven pump with a low amp shutdown in case the driver doses off and runs the pump dry. But an air powered diaphragm pump can run dry without a problem, also.
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No can do. I don't know if pressurized tankers have enough pressure to overcome the 20' level of the tank, since the connection is at the bottom of the tank. I was thinking of running pipe along the side of the tank so the tanker can fill from the top (above the liquid level). What are your thoughts?
It would take more pressure to fill the tank from the top than from the bottom. Filling from the bottom, you only have to overcome the pressure of the level in the tank. If you fill from the top, you have to overcome the full 20' to reach the top connection no matter how full the tank is.
Montemayor
Chemical
Let's not forget the basic input: the fluid is NaOH - a.k.a. Caustic Soda. This is stuff is hazardous and can easily blind/burn you.
Bottom filling is definitely not recommended - regardless of how much extra head you have to achieve on the loading pump in order to fill at the top of the tanker truck. The loading should be done at the top, not the bottom. The obvious reason is that ultimately someone has to disconnect the fill hose and deal with the resultant residual caustic in the fill line. I don't believe anyone wants to volunteer for that job. It's too dangerous and not necessary.
Bottom filling is definitely not recommended - regardless of how much extra head you have to achieve on the loading pump in order to fill at the top of the tanker truck. The loading should be done at the top, not the bottom. The obvious reason is that ultimately someone has to disconnect the fill hose and deal with the resultant residual caustic in the fill line. I don't believe anyone wants to volunteer for that job. It's too dangerous and not necessary.
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