I use mineral spirits as a degreaser on metal, usually removing manufacturing or packing residue. Usually, I use paper towels, let them dry, throw them in a sealable can and then store it until I have a place to drop it off.
But yesterday, I used a couple of old cotton bath towel to dry off something that was soaking in mineral spirits. The towel definitely has some on it, but very little. They are nowhere near soaked. I'd like to be able to wash and re-use the towels. I'm assuming it is safe to wash them, but I'm concerned about putting these in the electric dryer.
Is it safe to put these in a wash and or dryer? What precautions should I take before washing or drying in a machine?
Best Answer
There are 2 separate prongs to this problem.
Allowing flammable solvents into machines and sewer systems.
We don't want to wash towels that are contaminated with flammable solvents, because the vapors will wind up all sorts of places we don't want flammable solvents. That includes:
Certain flammables will self-combust
That is because they have a "curing" behavior similar to epoxy or concrete - and like most cures, it is exothermic. If that heat is sufficiently bottled up, it can rise to its own flash point and FWOOF! About 1700 house fires a year are caused by this. That generally relates to paints and stains.
However, I generally recommend developing the habit of handling all "oily" rags on the assumption that they will behave exothermically. I spread them all over the shop for a week to dry out, or better, leave them out in the rain.