The article is a bit light on. It appears to be playing with the miscibility of the oil under heat: Get a "sheet" of oil (obviously mixed with water) which holds together at ambient seawater temps onto the roller, pass it under heat and it stops holding together and drips through to the collector tank. So the hole sizes in the rollers, the rate of roll, the rate of forward motion must all be quite carefully tuned to just above drop through and then just below it.
It's not uncommon to process fat/liquid mixtures close to critical temperatures, butter handling in factories has to be within a very few degrees of specific ranges or risk over heating it (thats clarified butter) or burning it or it setting and clogging the pipes.
It's not uncommon to process fat/liquid mixtures close to critical temperatures, butter handling in factories has to be within a very few degrees of specific ranges or risk over heating it (thats clarified butter) or burning it or it setting and clogging the pipes.