I need a drain system that wont clog in VERY FINE, sandy soil that can handle 9-10 gallons a minute for hours. Ideally the system won't rely on fabrics to keep the fines out, since ALL fabrics used in my area seem to fail at keeping the fines out. The source is at 50psi, something that can handle pressure build up and not clog is ideal. If pressure builds up in the drain thats fine, just dont want it to result in fines infiltrating the chambers.

I was initially interested in a chamber system, but as I started to read they require geotextile fabrics to keep fines out of the chamber. Ideally the system wouldnt rely on fabrics, since all fabrics used so far in my area have failed. (Could I just buy a solid chamber with no slits in the sides? Maybe buy old culverts and cut them down the sides)

The other types of drains i've considered is a re-injection well, but i've heard the well heads can clog too if the water is high in rust. (Very high rust here). The re-injection well is interesting since the water is pressurized coming out and our water table is at 20ft. So a couple sand points hooked to the outlet might work perfectly, until they clog with rust.

And lastly maybe just trying the trench drain again, using lots of gravel and topping it and the sides with a thick plastic or some fancy geotextile that is better than the junk the drain tile socks come with.

Heck I'm even considering a combination of all 3 just to see which one will actually work. I plan to buy a backhoe attachment for my tractor, so digging lots isnt a concern.

Back story:
I have an open loop geothermal that pumps about 9-10 gallons of waste water per minute into drain tile with a sock. We have EXTREMELY sandy soil that is VERY FINE, the original drain tile (with sock) was clogged and replaced by the old home owner 2 years ago. When I purchased the place, the 2 year old drain tile was clogged with fine sand. I used a sewer jetter to clean it out and its maintaining currently. (Inspection pipes I put in show I need to clean it again)

Currently what happens is the drain tile builds up pressure (the pump is set to 50psi) and the water just gets forced out and often up onto my lawn. The full length of the drain tile is never used cause its clogged in lots of places. The places I had to dig and cut into in order to clean the pipe out from are prone to leaking up into the yard.

 

When I lived in a place that had fine beach sand, and sand would work itself into the small perforations, like between laid terracotta pipe, a "sock" was made around the pipe with gravel around the pipe.

So, here is what they did:
1. Dug a very wide (~45") and deep (deeper than 45") trench, 2. lay down fiberglass weed cloth, 3. lay down 18" of gravel, 4. lay 4" perforated (w/ bigger than "normal" perfs) PVC pipe, 5. pour gravel around the pipe so that it was 18" on each side and 18" over the top, 6. join cloth over the top and sew closed, 7. back fill.

Yes, eventually the sand will work itself into the perfs, but it's going to take a long time.