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