Petrol Condensation adds two new recipes to Factorio for turning lighter oil fractions to heavier ones.

1. 80 Petroleum Gas + 1 Coal -> 60 Light Oil
2. 120 Light Oil + 1 Coal -> 100 Heavy Oil

Both are unlocked when you research Advanced Oil Processing.

Known flaws

There's a bit of a halo around the new icons. Blame it on my lack of experience with working on alpha-channel images in Paint Shop Pro 7.