Description
The petrochemical generator allows you to generate power from "light oil", "petroleum", "ethanol" and "natural gas". Because of the fluid system in Factorio you can normally only allow one type of fuel in a system. This allows for all 4 fuels to be pumped into the system based on capacity.
The rightmost tank is the sensor. For natural gas (blue), petroleum (purple), ethanol (green), or light oil (yellow). The pumps to the left of the sensor tank are set to a greater than 2495 - the tanks hold 2500 so only if the system is maxed out will they pump into the second tank, the buffer tank.
The second pump reads from each tank above it - blue reads only pumps if "everything" "equals" "0" and is connected to the buffer tanks of purple, green and yellow with red wire. Purple does the same but connects to green and yellow buffer tanks with green wire.
Green buffer pump connects with red wire to yellows tank (which also means its connected to purple, and green also because of the blue wire connection) so it uses a specific "light oil" "equals" "0" condition so it only looks at the one specific fuel. Yellow pump is always enabled.
On the left hand size it goes from a connection to the right side that consists alternately of connections and one way valves so there is no back flow. The final tank at the bottom is for monitoring fuel status in the system. The decider combinator checks if "everything" "equals" "0" (meaning that there is no fuel in the system at all) it sends a signal to my a belt outside my coal power plant to "enable".
