How does the refinery module compare to the MISC Expanse's ability to run six separate refining jobs simultaneously, and does the module have any storage for refined ore on its own?

The Galaxy refinery module has both storage for raw and refined materials (outside of just saddlebag storage like the Expanse) as well as two reactors that are much larger than the Expanse's. So, while it can run fewer simultaneous jobs, it can process much larger quantities per job and store them after.