Originally Posted by ScubaSteve
Major breweries have covered boil kettles. There's an awful lot of drip-down. They vent the steam through chimneys to the exterior of the building....some actually use the steam to heat the building. I know New Belgium has gotten several "eco-awards" for doing this very thing.....
In that case with what you posted about "Major breweies have covered boil kettles. There's an awful lot of drip-down".
This tells me that there must be no worries about nasties getting trapped and not boiled out.
Boiling too long also reduces the hops oils and flavors hence adding more later towards the end of the boil time again.
With less water boiled down per given amount of time be it a 60 or 90 minute boil time this will allow for more net product at the end for the frementer.
With a large grain bill like a big Stout requiring 48.5 pounds of grain (off memory here would require 19.04 gallons of MLT volume).
After two or three trub and yeast dumps there still will be over 15 plus gallons in the fermenter to fill three 5 gallon corny kegs full.
I'm talking a MLT and boil keggle capable of holding 22 gallons of liquid.
The extra material on the keggle top from a cut 10" hole to the side of the keggle would allow more material to add vertical fittings plus a stainless sleeve for adjustment of the sparge ring heigth above the different mash levels.