Cool!
The only negative: if the inability to delete is really the main idea of the game (and not a consequence of the time limit), then confirmation before construction is very lacking. It's too easy to turn part of the factory into trash due to player misclick :(
But!
I like the setting of your factory. And I also liked some details of the gameplay: I want to pick up for my factory game the idea of turning a conveyor by moving the mouse within the border of one cell. This is really cool! I needed this feature!
Thanks for your work