Wort recovery from trub with a decanter centrifuge.

Ruggles, R.E. and Hertrich, J.D.

Abstract
The original wort recovery system at the Pabst Brewery (Newark) suffered from filtration problems, insufficient hot wort tank capacity and operator error on the cut-off level. It used water to wash the trub-cake which generated effluent. In the new system 92% of the hot wort is transferred to the cooler. The remaining wort (32 barrels) is used to slurry the trub-cake (rousing nozzles for 4 minutes). The slurry is transferred to the trub-holding tank at 32 barrels/h. The trub tank contents are then passed through a decanter centrifuge at 32 barrels/h. Recovered wort (92% with a solid content of 1.0-1.5%) is pumped to the cooler and trub (2.6 barrels/h with a solid content of 95%) pumped to the wet grain tank using a progressive cavity pump. A programmable controller is used to control hot wort processing. No adverse effects on wort or beer quality or fermentation performance have been noticed. The increase in wort recovery is 1.4% v/v at the decanter centrifuge and the annual saving in effluent charges $50,000.
Keywords: brewing centrifuge effluent recovery trub wort