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--- projects:vacuum_drier:work_logs:2_first_try [2022/10/18 05:29] – [Attempt 3] tjhowse
+++ projects:vacuum_drier:work_logs:2_first_try [2022/10/18 06:43] (current) – [Attempt 3] tjhowse
@@ Line 62: / Line 62: @@
 Mark 2.
-After a few false starts I managed to get the leakage under control. I pre-chilled the second batch of ice cream by putting it in the esky with the dry ice, rather than in the cold bath, to reduce the chance of contamination by methylated spirits. I bought a fresh bag of water ice and packed it around the food chamber, and sprinkled some salt into the ice to lower the melting point. I left it in the ice bath an hour or so until the surface of the ice cream began to develop a kind of foamy, crusty appearance.
+After a few false starts I managed to get the leakage under control. I pre-chilled the second batch of ice cream by putting it in the esky with the dry ice, rather than in the cold bath, to reduce the chance of contamination by methylated spirits. I bought a fresh bag of water ice and packed it around the food chamber, and sprinkled some salt into the ice to lower the melting point. I left it under a vacuum in the ice bath an hour or so until the surface of the ice cream began to develop a kind of foamy, crusty appearance. I took this as a sign that things were progressing well. About an hour later I took it the food chamber out of the ice bath and left it running overnight.
-I left this setup running overnight. In the morning I found the ice cream entirely melted, and the pressure at about 0.4 atmospheres.
+In the morning I found the ice cream entirely melted, and the pressure at about 0.4 atmospheres.
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 This would be the last attempt, as I was nearly out of dry ice. I pre-chilled about four strawberries and a dozen raspberries, then put them into the system with the last of my dry ice in the cold trap. After a few hours there was a fair bit of berry juice on the bottom of the food chamber. I put the food chamber into a 40°C water bath and the juice began to boil spectacularly. I could hear the dry ice in the cold trap bubble vigourously as it tried to keep up with the heat flux.
-After a few hours the cold trap was at around -50°C. I assumed it would not be able to do its job anymore so I shut it down and disassembled the cold trap.
+After a few hours the dry ice was gone and the cold trap was at around -50°C. I assumed it would not be able to do its job anymore so I shut it down and disassembled the cold trap.
 {{:projects:vacuum_drier:work_logs:pasted:20221018-051739.png}}