ANS:A - Rourkela (under SAIL)

The fertilizer plant getting its hydrogen requirement partly from coke oven gas is situated at Barauni (under HFC). Explanation:

1. Coke Oven Gas (COG): Coke oven gas is a by-product generated during the production of coke from coal in coke ovens. It consists primarily of hydrogen (H2), methane (CH4), carbon monoxide (CO), and other gases.
2. Hydrogen Requirement: In fertilizer production, hydrogen is a crucial raw material used in the synthesis of ammonia (NH3), which is a key component in nitrogen-based fertilizers.
3. Usage of Coke Oven Gas: Some fertilizer plants utilize coke oven gas as a source of hydrogen to partially fulfill their hydrogen requirements for ammonia synthesis. Coke oven gas contains a significant amount of hydrogen, making it suitable for this purpose.
4. Location - Barauni (under HFC): The fertilizer plant situated at Barauni, under Hindustan Fertilizer Corporation (HFC), is known to utilize coke oven gas as one of its sources of hydrogen for ammonia synthesis.
5. HFC - Hindustan Fertilizer Corporation: Hindustan Fertilizer Corporation is a major fertilizer manufacturing company in India, and the Barauni plant is one of its facilities known for its utilization of coke oven gas for fertilizer production.
6. Other Locations: While Barauni is specifically mentioned in the provided options, it's worth noting that other fertilizer plants in India may also use coke oven gas, depending on their setup and availability of feedstock.