What are components of Inert gas or IG system in detail?

Working of inert gas blower:

Blowers are used to deliver the scrubbed gas to the cargo tanks. Ships require at least two blowers which together shall be capable of delivering inert gas to the cargo tanks at a rate of at least of 125% of the maximum rate of discharge capacity of the expressed as a volume.

In some ships there is an additional small capacity blower which is used during topping up of cargo tanks.

5. Control valve

This valve adjusts the pressure in the inert gas line in accordance with the pre set pressures.

6. Deck seal unit

The inert gas coming from the IG blowers is sent to the individual tanks trough the deck seal unit .The main purpose of the deck seal is to prevent the back flow of  HC gas into the IG system and then into the boiler. The deck seal is an additional precaution in case of failure of the non return valve situated after the deck seal and before the IG isolating valve.