how big and in what geometry can you batch sparge?

Brewing Processes
1

I’m thinking about upgrading from doing 10-gal Denny-style batch-sparge brews in a big cooler chest, to doing 30-gal batches in a big 40+ gal stainless mash tun (maybe from Stout Tanks, or Psychobrew, or a Blichmann Boilermaker setup, etc).

Most of these seem to come with fancy things like “rotating sparge arms”, etc, which I don’t really even understand. So I’m wondering if I need to ditch my years of experience and comfort level with batch sparging and learn about fly sparging, which I’ve never done or even really thought about?

Or do you think with a system like that, you could still just drain off the first runnings, then add some sparge water, and drain again, just I’ve been doing. In other words, what does the increased mash volume and changed geometry (from a rectangular, relatively shallow grain bed to a more cylindrical and deeper bed)  do? Will efficiency be effected?  Any advice accepted.

-red

2

Based on my experience, it shouldn’t make any difference.  I sometimes use a 152 qt. cooler for large batches and it works just as easily and well as my 48 qt. cooler.

3

Does efficiency decrease as you scale up?

4

I can’t speak from experience but efficiency should be relatively constant assuming your qt/lb ratios are equal.  Since you are draining the whole bed, adding more water and draining again the size of the tun shouldn’t make a big difference.

IMHO, YMMV 8^)

Paul

5

In my case, it didn’t decrease.  Can’t see why it should aince you’re basically using the same ratios of grain and water to mash and sparge, just in larger amounts.  FWIW, Ihave a friend who runs a small commercial brewery.  He tried batch sparging with 500 lb. of grain and found that his efficiency actually went up!

6

The only thing I would be concerned with is losing heat in that size container. Otherwise I think as the others have said.

7

A larger volume should loose heat more slowly as the surface area to volume ratio is decreased.

8

True.  In a like to like comparison.  The OP is talking about going from a cooler to stainless steel so he will need to deal increased heat loss no matter what size he goes with.  Of course, he will likely go direct fired in that case so it should n’t be too hard, just a little more tedious, to maintain his temps.

Paul

9

I used to batch sparge 50 gallon batches and got 80%

10

To a certain extent.  In my 48 qt. cooler, I see an efficiency drop if a few points on beers over 1.080.  Although when I use the 152 qt. to make 10 gal. of something in the 1.100 area, my efficiency is pretty much normal.  I think that’s due to the larger amount of water I use.  Even in a smaller cooler, you can compensate by sparging oere (up to a point) and boiling longer.