Max. size of a Direct Fire System

[nani]

Does anyone have any idea (or experience) on the max. size recommended for a direct fired brewhouse?? I am concerned about caramelization and enzymes inactivation.
Thanx in advance for any input on this issue.
Cheers!!!

[brauerdave]

There are very large brew kettles(Pilsner Urquell for example) that have direct fire. Just depends ,to a certain extent ,on wether or not it's designed for direct fire.

[oppigards]

I have installed a lanemark tube direct fired burner which give me a heat transfer area of 3.2 sqm, compared with the bottom area of the kettle which is 1.5 sqm.

Very low caramellisation. Cleaning is not hard but I have to go down in the kettle to wash off the stuff.

http://www.lanemark.co.uk/

Cheers
Bjorn Falkestrom

[nani]

Thanks for the info Bjorn. How big was the system though?? Currently I am working with a 7 HL system and would like to consider bigger options (direct fire systems). Thanks in advance for your reply.
Cheers!!

[skagitbrew]

Bridgeport Brewery in Portland Oregon had, may still, a 40 BBL immersion tube kettle.

[beauxman]

I have worked on a 23bbl direct fire and made dark to light beers. other than scrubbing the coils to remove trub between batches, I would say it was a positive experience. I would think that the larger batch size vs the smaller batch size would lend even less caramel reaction impact based on surface contact ratio.

[Moonlight]

I am currently using a 21 bbl direct-fired (atmospheric) kettle. It needs to be designed, built, and adjusted to get everything right. Gas is expensive and a lame boil will likely frustrate you and your beer. Do not assume one could do this by just sticking a burner under any tank. I believe the de Clerck book has a good section on firebox design.

[oppigards]

The gas burner includes a gas train which has one max and one low effect step. The kettle gross cap. is 2300 litres. The efficiency is approx 92 % and max heat gives 150 kW. 150000 w/1,16 * 92%/2300 = 2300 litres rises 56 deg. celsius during one hour. The low effect step gives about 60 % of max effect. I have a 12 meter long immersion tube which is welded as a spiral. A bad thing is that I can not boil less than 1600 litres. But I have heared about other installations which have made the tube shorter and not that high.