It’s damn annoying that some of the “disposable” pepper grinders (the kind made by spice manufacturers and sold at grocery stores) can’t be easily opened so they can be refilled and re-used when they are empty. I recently found myself with an empty disposable pepper grinder at the same time that I couldn’t locate my salt grinder. I thought I could wash it and fill it with sea salt, but … it’s made so as to be very difficult to open.
Here’s the trick: Soak the plastic top in very hot water for several minutes. This makes the plastic just a bit more flexible, which should allow you to pull the plastic top off the glass jar. Just hold the glass jar in one hand and the plastic top in the other and pull them straight apart. Then you can dry it and re-fill it. Once it’s refilled, to put the top back on, just press the top firmly onto the jar.