I had originally written up a ''Full Disclosure'' OP, but took most of it away thinking it wasn't needed. Well, here goes:
We live in a wetlands area, and it's not unusual for our sump pump to pump even throughout the long Minnesota winters. We've had times when the sump pump pumped over 2,400 gallons per 24-hour period for months on end!! 20 years ago, I started with 1 1/2'' PVC pipe with heat tape. That worked OK, but the run wasn't long enough (only 40') and the water would drain through the ground back into the basement! Due to the low nature of the basement, that drain pipe comes out just 14'' above ground level. The longer the run, the more level the pipe. AND, the pipe has to be at least several inches off the ground to prevent ice buildup and eventual blockage of the pipe.
Later I switched to 3'' PVC. A sump pump can pump quite a bit of water, but not enough to fill a 3'' pipe. That pipe runs about 70' to the outside, but still creates problems in winter. Water will collect in between the pipes and, when it freezes, the pipe 'pops'. I've come to learn that the pipe is spreading apart. I have to use rubber connectors. Tried gluing the pipe, but when things go wrong at -40F, it's no fun trying to find the frozen spot(s), cut them out, clean, then re-glue them. So I use rubber connectors, which spread apart over time.
This next adventure will be using a small oil-free air compressor (
https://www.amazon.com/gp/product/B07CKRLKM9/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1) that will fill its own tank (4.7 gal), plus the 11 gal tank. Both tanks will be situated so that all outgoing air exits the bottom of the tanks. All of this will be located in the basement, but that is a very wet area when the system will be needed.
I will be pumping the water through a 300' length of 1" PEX rated at 250 PSI. Come Spring, that pipe will get buried a few inches below the surface. The far end will angle up about 20'' above ground so that ice will never build up to where the water cannot exit.
There will be a 300 gallon tank for holding sump pit water. One small pump will necessarily cycle frequently, pumping its contents into the larger tank. Then a slightly larger pump will pump the water out.
When the tank nears empty, a float in the tank will shut off the pump and also trigger the release of air. That air will dump both tanks. When the air pressure drains to a low enough PSI, the valve will close so that the small compressor can refill both tanks. That should take less than 5 minutes, so that's easily enough time for recovery. MFGer's website says it fills the 4.7 gal. tank (0 to 125 PSI) in 106 seconds. Larger tank will only fill to 100 PSI. Should actually take just under 4 minutes.
This system will not be portable. It will be rigidly mounted so that outlets face downward. Everything [u:a4ff0947e2]must[/u:a4ff0947e2] be secure. Therefore, I want to treat the tanks one time, and one time only. I think this will work, but wanted to get the thoughts of the rest of you.
The compressor tank will fill to its max 125 PSI. Air to the 11-gal tank will be regulated to 100 PSI. As 11-gal tank is depleting, the air in the small tank will also be draining into the larger tank, effectively giving me appx. 15 gallons of 100 PSI air -- more than enough to evacuate the water from the 300' pipe.
I've read where straight boiled linseed oil has been used to coat the insides of motorcycle frames. Once dry, it protects against the frames rusting from the inside out. However, with the amount of moisture that will definitely be going through this system, I think it's more practical to add about 20% by weight paraffin or beeswax. Once dry, it would provide a fully waxed and fully waterproof coating. No sunlight means it should last indefinitely, right?
Every part of the system will be mechanical. When X happens, that triggers Y & Z, so to speak. It will be a hands-off system. Also, these two tanks will be located inside the basement of an old farmhouse. If anything ever did malfunction and go BOOM, then there's a good chance it could collapse a portion of the main floor! Yes, most leaks in air tanks are pinhole leaks, but again, this will be pumping very humid air into the tanks. I've also read how tanks will rust out faster if not FULLY coated and protected, so I will likely do the coating treatment twice, spending several hours to ensure complete coverage. ...Guess I could buy an endoscope though. Then I could look inside and check the progress.
Your thoughts????