High pressure pump recommendation for hot water

[acewolf187]

Hi all,

Does anyone have some experience with a reliable pump type (and possibly reputable manufacturers) for high pressure/relatively low flow applications. I require one to pump 2 m3/hr (9.2 US gpm) of 90°C (194°F) water and generate a head of 750 m (2460 ft) ~70 barg. It will run 24/7, be inverter-driven and I need it to reliably produce the expected flow for any given frequency for extended periods.

Thanks in advance.

 

[LittleInch]

At that flow and pressure you're probably best off with some sort of piston PD pump. Vendors? Most of the good ones are all now owned by one or two companies regardless of the name on the tin.

Pressure control needs to be considered and either matched to pump speed or have a flow return system to control the pressure.

Why invertor driven? You only state one flow rate and one pressure.

your requirements are a little on the small side, but really nothing too special.

"High" pressure or temperature means different things to different people....

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

 

[Artisi]

Can't see anything too special about the duty, an internet search should give you plenty of leads.

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.)

 

[1503-44]

Or multistage axial.

 

[goutam_freelance]

There are various suppliers so that is not a problem. With such a low specific speed only piston pumps may be suitable. The following could be important in design of system.
1. There will be pulsation at suction and discharge. So some type of pulsation dampeners may be required at least for suction.
2. Since you are pumping hot water, the NPSH may be an issue. Try to have a pressurized of flooded suction. For these pumps you need to add 'acceleration head' in NPSHA calculation. The suction lines must be very short.
3. Max piston speed should not be exceeded at max motor speed. The piston speed should be as low as possible to prevent boiling of hot water in the low pressure region of piston/cylinder.

Reputed manufacturers will be able to provide more information.

Engineers, think what we have done to the environment !

https://www.linkedin.com/in/goutam-das-59743b30/

 

[1503-44]

Oh right. I read m3/s, or better, not at all.

 

[acewolf187]

Thanks for your responses.

Reliability is an issue for this duty and I am determined to choose an excellent replacement pump, hence me seeking as much wisdom and experience as I can get.

@LittleInch, you're quite right, "high" is indeed a relative term. My shortlist consisted of piston, screw & diaphragm pumps, I am now tending towards a piston pump. It needs to be inverter driven because it feeds a heater whose rate is based on the pump's inverter frequency (rather than the flowrate directly; this doesn't appear to be the best control strategy but it's on the list of future improvements).

@1503-44, I did look into multistage centrifugal pumps and yeah, they would be great if it were 2 m3/s rather 2 m3/hr.

@goutam_freelance, many thanks for your post. Points 1 & 2 have already been considered and adopted, although the suction lines couldn't be kept short enough so a booster pump was provided and the pipe diameter oversized to reduce the acceleration head. Point 3 is very useful to know and will be taken on board too.

Thanks again all.

 

[LittleInch]

At that sort of flow you're into metering pump territory. Very controllable.

Try

https://www.lewa.com/en/applications

and chose metering pumps

https://www.kinder-janes.co.uk/prod...s/metering-pumps/ecoflow-high-pressure-range/

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

 

[EdStainless]

Hot pressure washer pumps are common. Usually with ceramic plungers. Lots of options.

https://www.catpumps.com/search?sea...essure_min_bar=1200&field_pressure_metric=psi

https://www.powerwash.com/comet-tw-8030-s-solid-shaft-hot-water-pressure-washer-pump.html

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[acewolf187]

Thanks Little Inch and EdStainless, those are very good options.

What are your thoughts on piston vs plunger pumps. I was tending towards piston pumps but a little research suggests the seals on plunger pumps last longer due to being stationary.

 

[goutam_freelance]

Plungers are normally used for more than 2000 psi pressure with max plunger dia about 5 in. With pistons you can make it double acting reducing the cost. Manufacturers may be able to give you the optimum solution.

Engineers, think what we have done to the environment !

https://www.linkedin.com/in/goutam-das-59743b30/

 

[acewolf187]

Thanks Goutam_freelance.

 

[georgeverghese]

Piston pumps are a messy way of getting a liquid from A to B - they may be cheap, but pulse a lot, and are not reliable at all. In this application, pulsations from the cheapo piston pump could ruin your HX/ heater coils in no time.

Plunger pumps are relatively more reliable, still pulse and present NPSHa problems in this application. Metering / screw pumps may be possible, but viscosity issues (low lubricity with hot water) may get in the way.

Fig 10-26 in Perry, 7th edn tells me a multistage centrifugal at say 30gpm, 2500ft is possible. You could run this centrifugal on-off to feed a surge drum that is gas pressured at say 72barg. This pump runs on on-off level control from this surge drum. An exit stream from this drum feeds the heater on flow control at 2m3/hr as required. No pulsations, higher reliability, no NPSH issues.

 

[acewolf187]

Thanks for the suggestion georgeverghese.

 

[hydtools]

Look into waterjet pumps.


Ted

 

[TiCl4]

You could also install a recirculation loop with a draw-off. Set up the centrifugal pump to recirc to a suction tank. Tee off of the recirc header with a control valve (Badger RCV valves are low-flow valves that are rated up to 5,000 psi, for example) and flowmeter. That eliminates any pulsations and gets exactly the flow you need based on incoming frequency.

Depending on how large the recirculation pump power draw is, you may need to cool the recirc flow to maintain your 194 F temp. It'll depend on your draw rate vs pump power input.