Basic Chemical Plant Process Automation

Hi,
I'm new to the chemical field. I'm actually an electronic student. I'm doing a written report about how to implement PROFIBUS technology into a chemical plant.
I have the following queries,
a) what are the complete process sequence for a substance to undergo all the process until it becomes a product? Is that extraction, reaction, absoprtion...?

Could anyone tell me or show me a better idea on how a chemical plant operates?

Thanks for all your attention.
Regards
wcz