The Effect of Grain Bed Depth and Cross-Sectional Area on Filtration Flow Rate Flashcards
(19 cards)
What does Darcy’s Law state regarding grain bed depth and filtration flow rate?
Decreasing grain bed depth will increase filtration flow rate, and vice versa.
How can grain bed depth be reduced while maintaining a given malt charge?
By increasing the bed cross-sectional area.
What is the minimum bed depth required for the lauter tun to achieve acceptable wort clarity?
Around 500 mm.
What is the minimum bed depth required for the mash tun with a coarser grind?
1,000 mm.
What is the grain bed depth used in a mash filter?
50 mm.
What is the relationship between grain bed depth (L) and grain bed cross-sectional area (A)?
For each mash separation device, Darcy’s Law provides relative filtration flow rates.
What is the grain bed loading for a lauter tun with 11 t?
200 kg/m2.
What is the grain bed loading for a mash tun with 11 t?
500 kg/m2.
What is the grain bed loading for a mash filter with 11 t?
30 kg/m2.
What is the tun diameter for a lauter tun?
8 m.
What is the tun diameter for a mash tun?
5 m.
What is the tun diameter for a mash filter?
20 m (58 filter chambers).
What is the relative flow rate for a lauter tun?
5.
What is the relative flow rate for a mash tun?
1.
What is the relative flow rate for a mash filter?
330.
True or False: The mash filter is predicted to run 330 times faster than a mash tun according to Darcy’s Law.
True.
Why do we not get the same mash filter flow rates as predicted by Darcy’s Law?
We must consider grain bed permeability.
Fill in the blank: The mash filter requires a very high surface area, which is accommodated in _______.
[multiple chambers]
What is the effect of reduced grain bed depth on filtration?
Results in faster filtration.
