I very much enjoyed the concept, the gameplay loop of planet destruction and having the materials drop through the refinery area was very satisfying. I didn't encounter any issues during gameplay, though a couple times I missed an explanation for a mechanic (mostly an issue on my part and figured things out pretty quickly, just noting for future reference if you decide to expand on the concept).
I can definitely see this concept working as a fleshed out game and the refinery system has a lot of room for added mechanics and complexity. Currently once I understood the gameplay I created one refinery set up and stayed with that the entire run, I feel adding new features through unlocking that require you to rethink the setup or tinker with it could really add to the gameplay. Having ore mixes for more value is very neat, maybe a system around that mechanic that requires different alloys simultaneously might incentivise players to create more complex workflows (maybe some sort of basic logic system like sorters or gates that only open when a condition is met).
Just a few things that came to mind while playing, hope you expand on this, it has potential and look forward to seeing what you do with it.