Lesson 6 - Wort Separation Process Control
This lesson deals with wort separation process control. The different methodologies of measuring and calculating extract recovery are explained and demonstrated. A methodology is explored, as is how to investigate and resolve performance issues with extract efficiency, wort quality, and cycle time.
Sparging Inefficiency
Mash Tun/Lauter Tun
Correct formation of the grain bed is critical. It is also critical that we maintain its integrity during wort collection. If the grain bed is unevenly distributed, then sparge will flow preferentially through the thinner sections of the grain bed. We need to visually inspect and confirm that the grain bed is level.
As mash separation progresses, it is possible for the grain bed to crack. This will allow even more pronounced preferential sparge flow. Observation of the grain bed during late sparge should reveal an even bed with no cracks.
With multiple outlets in the true floor, it is possible that some of them have become blocked. This means that the other areas of the bed will receive preferential sparge flow. How do we know if this is happening or not? We will need to lift the false floor plates and inspect each outlet. Use of a hosepipe will confirm free flow, or not!
It is also possible that some of the underfloor cleaning nozzles have become blocked or faulty, resulting in blockage under some sections of the false floor. Flow under these sections of the grain bed will be restricted, resulting in preferential sparge flow in other areas of the grain bed. Again, we can only determine if this is the case by lifting the false floor plates. We need to inspect for silted up areas and/or blocked false floor slots. We also need to check for the faulty cleaning nozzles that have caused the problem.
Sparging Inefficiency – The Mash Filter
Uneven flow into and out of each mash filter chamber will cause variable grain bed loading. The grain in any lesser loaded chambers will be less compacted and will offer an easier flow path for the sparge water. This will cause variable sparge flow between the chambers. How do we know if this is happening? We need to inspect each mash filter plate and inspect for any blockages of the mash/sparge inlet ports.
Uneven chamber filling can also be caused by resistance to flow caused by blocked filter cloths or blocked wort outlet holes behind the filter cloths. So in addition to inspecting the mash/sparge inlet ports, we need to confirm that filter plate outlet holes are not blocked, and that none of the cloths look more heavily soiled than the others (indicating a cleaning issue).