Abstract: The subject matter of this specification can be embodied in, among other things, a mixing system that includes a heating assembly configured to heat liquid, and a mixing assembly including a tank defining a cavity and configured to retain liquid, an inlet in fluidic communication with the cavity and configured to receive liquid from the heating assembly, a mixing impeller assembly configured to mix contents of the cavity, an actuator configured to actuate the mixing impeller assembly to mix contents of the cavity, and an outlet in fluidic communication with the cavity and having a valve configured to selectively prevent and permit egress of contents of the cavity.

Abstract: Compositions for forming protective coatings can include a first group of compounds, where each compound of the first group is a fatty acid, fatty acid ester, or fatty acid salt having a carbon chain length of at least 14 carbons. The compositions can optionally include a second group of compounds selected from fatty acids, fatty acid esters, fatty acid salts, and combinations thereof, wherein each compound of the second group has a carbon chain length from 7 to 13 carbons. At least some of the compounds of the first group can function as emulsifiers, allowing the composition to be dissolved, suspended, or dispersed in a solvent. At least some of the compounds of the second group can function as welling agents in order to improve the surface wetting of items to be coated when solutions, suspensions, or colloids that include the compositions are applied to the items.