LM still, positive vapour flow from top of still column
Posted: Fri Jan 29, 2021 11:21 pm
I recently did a beer stripping run on a new 60L LM still build and was checking amongst others a variety of things. ...
Cooling water take off temperature at RC top ..... outlet
Temperature of distilled product take off after PC
Top temperature at column top (where I have a DN25 CIP connection)
I was using ambient tap water for the supply cooling water ... +- 20 deg C estimated and atmospheric temp was approx. 29 deg C.
Cooling water temp during stripping at outlet of top RC not accurately measured but I estimated about 36 - 40 deg C
Distilled product temp was generally < 30 deg C (measured Edrometer)
Top temp at column top (above RC where CIP connection is) was not hot (hand measurement) and I estimated <40 deg C
But this is when I discovered that I had a positive cool vapour flow from top of column (CIP connection)
Beer being stripped was approx. 5% ABV and had been open to atmosphere for a few days so a lot of saturated CO2 gas had been removed
Power to the boiler was approx. 2.5KW
I was at a loss to explain why I had this positive cool vapour flow and possible alcohol loss and ultimately fitted a safety pressure relief valve to this end connection.
Any suggestions regarding this cool vapour flow ???
Thoughts coming to mind;
Flooded column from beer ?? I have no sight glass fitted so can not confirm. I don't think so
Take off needle valve too small so restricted flow (1/4" standard off the shelf needle valve) ..... I was stripping with valve 100% open
I did increase cooling water flow but no difference realised
Cooling water take off temperature at RC top ..... outlet
Temperature of distilled product take off after PC
Top temperature at column top (where I have a DN25 CIP connection)
I was using ambient tap water for the supply cooling water ... +- 20 deg C estimated and atmospheric temp was approx. 29 deg C.
Cooling water temp during stripping at outlet of top RC not accurately measured but I estimated about 36 - 40 deg C
Distilled product temp was generally < 30 deg C (measured Edrometer)
Top temp at column top (above RC where CIP connection is) was not hot (hand measurement) and I estimated <40 deg C
But this is when I discovered that I had a positive cool vapour flow from top of column (CIP connection)
Beer being stripped was approx. 5% ABV and had been open to atmosphere for a few days so a lot of saturated CO2 gas had been removed
Power to the boiler was approx. 2.5KW
I was at a loss to explain why I had this positive cool vapour flow and possible alcohol loss and ultimately fitted a safety pressure relief valve to this end connection.
Any suggestions regarding this cool vapour flow ???
Thoughts coming to mind;
Flooded column from beer ?? I have no sight glass fitted so can not confirm. I don't think so
Take off needle valve too small so restricted flow (1/4" standard off the shelf needle valve) ..... I was stripping with valve 100% open
I did increase cooling water flow but no difference realised