Emerson chiller?

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Probably. Haven't ever heard of doing it this way. Personally I'd be worried about cleaning the inside of the coil and being able to inspect it . . . and that would be regardless of the chiller's name. BTW, the trub doesn't form a cone until after all whirlpooling has ended and been allowed to settle for a while.

 

You will need a ton of ice if you pump cooled wort back into hot wort.

 

I feel like you would need more than a 5 gallon bucket. I have not tried this, but believe it has been talked about before. I think cleaning would be easy, at least it would be like other pump set ups that I have seen people use. the hard part would be getting what you need to cool the beer down. You might be able to get to a whirlpool temp well, but feel you would struggle to get lower then 110 degrees F with out a bigger reservoir. also you would probably need to move the chiller or circulate the water around it.

I have never used a counter flow chiller before, but could you make one work for this purpose? I feel it would be better suited for this kind of thing but am not sure. I am also assuming that you have a immersion chiller and don't want to buy a counter flow.

 

Why would a ton be needed for that, as opposed to a half-ton for another method? (not that I think recirculating wort through copper coils in a bucket of ice is the best option).

 

I tried something like it except i had a 5 gal bucket of water/ice with a submersion pump inside of a chest freezer that fed a immersion chiller then returned and the bucket of water took a long time to cool the wort even though the freezer was set for 20 degs. If he froze a lot of ice and had a bigger container it would work. I use a 100 gal tank that usually has 4" of ice in the winter.