Enthalpy

A few days ago, in the midst of the recent cold, I went up to give the pigs their afternoon whey. I pulled open the valve on one of the tanks and heard the swoosh of moving liquid. It continued for a few seconds and then it just stopped. Nothing was coming out of the filling pipe, even though I was certain I had drained it that morning. In my experience moving liquid usually thaws out anything it’s touching, so what could have made it freeze so fast that it could clog a pipe?

Over the past week the battle has continued, with the whey going from liquid to solid impossibly fast. Slush starts forming the moment it hits a tank or bucket, and it is becoming a struggle to keep valves from freezing shut. The grimest prospect, which the warm forecast for later this week will hopefully prevent, is of whole tanks completely siezed up, leaving me with no easy method to keep the pigs watered (or wheyed, as the case may be).

So why is the whey behaving differently than ever before? My best guess is the degradation of bales around the tanks - hay is a good insulator so long as it remains intact, but it’s not so effective once it’s composted to dirt, as has most of the stuff that previously held off the worst of the cold. This has led to the whey cooling faster than in past winters, which brings me to an experiment you can do at home.

Put a container of room temperature water in your freezer with a good thermometer placed inside it. Take temperature readings every few minutes and plot them on a graph. It should look something like this:

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