Submersible pump

Zman

I am looking at a project that would require a pump that would require a pump that will fit in a 4" well casing approximately 180 feet deep. It would need to operate with 160 degree water that likely has high mineral content.Does anyone have a suggestion?
I will post the details of the project in the future, just looking to give him a ballpark budget on the costs at the moment.
Thanks,
Carl

Jamie Hall

All I can say right off hand -- I've not been spec'ing pumps for a couple of decades -- is that those conditions are downright nasty for a submersible. They depend on the water they are submerged in for cooling the motor. Any chance you can go with a deep well turbine instead (with the motor on top, and a line shaft driving the actual pump)?

Also, with the high mineral content I would make sure that everything that can possibly touch the water is rated plastic or bronze -- or for the seals (which will take a beating) possibly carbon.

RobG

you might want to contact @Radiator Ranger, I think she lives on a property with a really hot hot spring. I believe ME has been out there to help with the place (my memory isn't what it used to be)

Zman

Rob,
That is a good lead http://contractormag.com/columns/eatherton/largest-heat-source-part3-1210
At this point the client is trying to figure out how to navigate the oddball water laws in the west to see what he can really do.
I love the idea of the down well heat exchanger, I'm not sure it is allowed. I am sure at some point I will be reaching out to Mark and Gwen (Radiator Ranger)
Thanks,
Carl

hot_rod

Sometimes if you dig deep enough at pump manufacturers websites you fined a "build" list. It asks you to answer all those questions then suggest models that fit.

Yeah, I think that 160F, and small diameter may be a deal breaker.

I looked for a high temperature submersible for an underground solar drainback tank once.
I found a manufacturer that built pumps for molten solder, maybe for printed circuit boards? The were crazy expensive, thousands of dollars, and nowhere near the capacity I needed.

I visited a mikvah job in NY a few years back that Kal and Moses worked on. The were not allowed to use pumps to get the water from the wells they drilled, so they had these huge compresser in the basement that pushed air down the hole to lift the water out.
I had pictures from Moses of that venturi rig that went down the well hole, I'll look around.

A venturi would solve the temperature and mineral issues possibly. Some emergency sump pumps work that way also so no power is required, just city water pressure.

Zman

Hot Rod, I really like the idea of any kind of indirect drive pump.
The other item I came across in looking at ME's project is an down hole exchanger.
I hope the 4" does not become a huge limiting factor.

hot_rod

Here are some pics from that job. Actually the water was "burped" from the ground with compressed air, or collected from the rooftop. I thought it was a venturi, sorry.

Also the tube that went down the hole to force water up.

Probable more than a 1 hp contractor compressor needed to fill that tube with air.

It was amazing how the did all this work in the tight confines of the city.

Looks like the drillers had plenty of advice.

For your project, maybe a ceramic heat exchanger, sounds like that water would be very aggressive and scale forming, and need frequent maintenance?

Dwight from Rhomar tells me with hot water every 20° of temperature increase, the corrosion rate doubles.

Jamie Hall

I've used that type of compressed air system (only in my settings it was compressed ozonated air). It works really well -- provided the required lift isn't too great. It is not, however, particularly efficient!

How deep is it to static water on this job?

Zman

I believe the well is 180' with a waterline at 140'.
15 gpm is what the driller rated the output.
They don't anticipate needed more than 5 GPM

JUGHNE

Would a 2 pipe jet pump work down at that depth? The inducer goes down to the bottom of the drop line. Economical if it would do the job. Just change the pump as needed.

Jamie Hall

JUGHNE said:

Would a 2 pipe jet pump work down at that depth? The inducer goes down to the bottom of the drop line. Economical if it would do the job. Just change the pump as needed.

I'd have to check the specs -- 140 feet lift is quite a lift for a jet pump. Yes, I imagine that an inducer could be found with a diligent search that would manage it. The operating efficiency is going to be pretty low, though. At least you wouldn't have to deal with motor cooling -- but you would still have that aggressive water... I still prefer a deep well turbine, if you can find one that fits that casing. Gets around all the problems.

JUGHNE

A casual search talked about 80' depth, that was the residential type websites. It seems there would be a 2 stage with the first inducer pulling up on the lower stage.

Jamie Hall

JUGHNE said:

A casual search talked about 80' depth, that was the residential type websites. It seems there would be a 2 stage with the first inducer pulling up on the lower stage.

I'd found 125 feet in a three stage commercial pump. So they are out there... somewhere. I didn't look that hard!

Zman

I wanted to revive this post.

The original property purchase fell through but the client has found another similar deal.

This one has a 6" well with a reported 105 degree water temp. Someone had made a recommendation for a down hole (bore hole) heat exchanger that was resistant to corrosion and fouling. I can't find the name...

Has anyone done a hot tub that is heated indirectly with tubing embedded in the concrete? If so what king of temps would be needed to maintain an outdoor tub?

Hope this one happens, fun stuff.

hot_rod

An outdoor tub in a winter climate?

I tried a to heat a small concrete pool here in Missouri with tube in the concrete. The numbers showed it would not work, the Dr had me do it as a trial anyways. I was shooting for low 80 operating temperatures.

I used 2" foam with ThermoFins and pex 9" on center.. no go.

I ended up using a pool HX on the TT boiler that was installed to the tube, so still a nice system.

Zman

It must be the evaporative heat loss. From a surface area point of view it sketches out as doable. I did not look too hard at it...

hot_rod

Zman said:

It must be the evaporative heat loss. From a surface area point of view it sketches out as doable. I did not look too hard at it...

This pool had a well insulated automatic cover, and it was used at any time the pool was not. It was a fairly small swim spa type of pool. The type with the big jet flow that you swim against. As I recall it was a therapy pool for one of their kids.

It's been 12 years or more, Siggy ran some FEA and calcs for me, I'll see if I kept any of that data. I did keep pics taken with the old Sony Mavica His analysis predicted it would not work. It didn't, but I don't know how much if fell short. The tube was in the floor only, the type of construction didn't allow for all the walls to be tube. Maybe the walls were fiberglass panels.

In this area you get maybe 3 months without any heat source. Mainly heated pool here are trying to extend the season a few months, not a year around outdoor pool season. For residential customers anyways.

Zman

Hot Rod,
Thanks for the reality check on the radiant heat. Sometimes I want something to work so badly I ignore the math.
I sent the owner out to the property to get some water samples and do some data logging.

hot_rod

A group of us got a tour of the GEO well and system at the Peppermill in Reno recently. The submersible in their well at about 400' pumps 165° water. The pumps and heat exchanger appeared to be standard components. I asked the maintenance engineer if the pumps, including the reinfection one pictured here, or HX were built specifically for the water conditions.







He did mention that the water quality was much better than expected and the had prepared for a bi yearly disassembly of the HX. They opened it the first year,added additional plates and have not serviced it since. Plenty of data point indicate performance and when maintenance is required.

Depending on the water quality in your well, I think having the HX up in the mechanical room would be preferred for service.

I'm not sure what type of HX you would get into a 4, 6, or 10 well casing?

Zman

I am trying to remember where I found the info about a 6" down hole HX. I think it was a company Max knew of.
If you put the HE aboveground, how would you put the water back in the well? I guess you could have a second pitless adapter for the return. Would you return the water just below the water level in the well?

Mark Eatherton

I'd suggest a venturi foot valve like https://www.zoro.com/dayton-deep-well-double-pipe-4-in-4hfa9/i/G2189451/?gclid=COPm5KmY1tACFQ5Efgod2SMKrQ&gclsrc=aw.ds

You don't want a pump submerged in nasty conditions in a deep well. I'd draw from the upper part of the system and return to the lower part of the well. This should enhance the natural water buoyancy tendencies. As others have also noted, after you get the test results back, select components accordingly.

The project in Washington state had a 2" schedule 80 pipe as its heat exchanger. When we flushed it with the fire truck, we got a LOT of rust/scale out of it. I didn't see any water quality tests, but told them they needed to budget for a new heat exchanger. I'm not sure if Gwen is still with them or not. I occasionally speak with a few of the folks up there, but haven't heard from her in years.

Zman, is this project in N.W. Colorado (Craig) per chance? I consulted on a project that sounds real similar, except this guys well had artesian tendencies. His well was an abandoned natural gas well. I'd speced WarmBoard throughout, then he told me he wanted to roll a wrestling mat out on his basement floor. Seriously. I told him it wouldn't work, and he said he was going to go with a GSHP. I wonder how many heads he's blown off his compressor...

ME

hot_rod

Zman said:

I am trying to remember where I found the info about a 6" down hole HX. I think it was a company Max knew of.
If you put the HE aboveground, how would you put the water back in the well? I guess you could have a second pitless adapter for the return. Would you return the water just below the water level in the well?

There were about 8 GEO wells on the Peppermill property, most abandoned for the newest high flow one. The all re-injected into separate wells.
One of the fellows on the tour taught the GEO operators course at the local CC. He claims you cannot, or should not re-inject into the same well. Into the same aquifer level, but some separation.

The well and re-inject well were about as far apart as their property allowed at the Peppermill, maybe 1/4 mile or more.

The pump pictured above is the reinject pump, mounted near the re well.

Zman

Mark,
This one is in the Collegiates. Thanks for the recommendation. I am interested to see what the water temp and chemistry looks like.

Hot Rod,
I don't know if a second well is an option. They did use perforated pipe for casing for the ~40 feet the well is in the aquifer.

Thank you both...

Jack

I would suggest that you contact the Geo-Heat Center at the Oregon Institue or Technology in Klamath Falls. If it is direct geothermal in the West, they have tested the resource. That can likely tell you the history and make material recommendations. They are an excellent outfIit. If there is a "flow gradient" to the resource, as they have in Klamath Falls, you can use a DHHX. I worked with them and the Ca Energy Commission in Calistoga, CA in 1980 to analyze the direct Geo possibilities. There is a pool of hot water there with no flow gradient, so no DHHX.