Ya know, before newb's start rehashing old ideas again in another thread for the umpteenth time you might want to first read
Why so few immersion cooled custom builds/Mods? to save a lot of brain power...
Pretty much covers most of the in's, out's, and gotcha's. Also a better place to continue the discussion vs making another thread on the same subject.
Thanks for the link to the other thread, I read through that and it was informative. Mostly about immersion cooling though. I was actually thinking of making a heat exchanger that you could direct mount the hashing boards onto, and replace air cooling. If it already exists, cool. The thing with this approach is that it can be pretty cheap and potentially open for DIY using off-the-shelf parts. Immersion cooling and the like all look to be quite expensive.
In most ways, immersion is cheaper and a lot easier as the same pumps/fluid/air exchanger setup is used but:
No time spend tearing apart miners and installing cold plates.
No plumbing manifolds with hoses using dripless tubing connectors feeding each miner/hash board
Just drop in the miner and trick the fan speed monitor into being happy
Using cooling blocks are a different story. Yes they can be used on S1 through the s5's. There are already folks here that made them long ago. Do a search for 'Antminer cooling block' and it should turn up folks that might still sell them. On the commercial product side, search Wakefield Cold Plate for their offerings and a ton of information regarding sizing everything.
As for S5+, S7 and S9/T9, forget it. The chips are in strings and there is a serious likelihood of causing a short-circuit. Then there is the issue of removing the original heatsinks used in them - very difficult to do without causing damage.
As for the heat exchanger you mentioned... Physical size tells next to nothing. You need to find out what its thermal specifications are! Being very familiar with various cooling systems including industrial chiller systems and outdoor cooling towers I can say that 24"x48" is NOT going to be able to dissipate 300kw... depending on fluid flow rate, airflow and delta-T between the air and fluid - 10kw maybe.
Lastly, the S9 and T9 CANNOT be overclocked. They are already pushed to their limits (which is 1 reason the s9 has such bad reliability) and their freq/core voltage cannot be changed.