Anjana Reghuraj | October 22, 2022

Full operations will continue at CPCL according to authorities

There are no solutions in sight to the pollution problem faced by the residents of Manali, an industrial town in North Chennai. The residents have been complaining of breathing problems and skin allergies due to the persisting LPG-like odour (the smell of sulphur-dioxide) in the air, allegedly from the emissions of Chennai Petroleum Corporation Ltd (CPCL).

The Tamil Nadu Pollution Control Board (TNPCB) allowed the CPCL to resume full operations 15-20 days after it ordered the company to cut its crude oil refining process to 75 % on July 15. The initial order to reduce capacity was in response to the complaints about foul smell from the Manali and Thiruvottiyur residents.

TNPCB appointed a team equipped with portable volatile organic compound (VOCs) monitors to check the air quality at seven different places around the industrial area. Continuous ambient air quality monitoring stations (CAAQMs) were installed in the upwind and downwind direction of the refinery.

The state government appointed technical committee suggested that reports of crude oil consumption be submitted daily, to ensure maximum sulphur recovery and quantity of sulphur recovered. TNPBC ordered the company to follow the same.

CPCL carries out the process of refining the crude, in the process, they reduce sulphur content in the crude oil using the sulphur recovery unit. When the threshold limit of the sulphur exceeds, automatically the safety valve opens and it will let out the acid fumes containing sulphur.

As CPCL is a major refinery in the area, the TNPCB assumed that it was the source of the odour. However, they were unable to confirm that the source of the odour was CPCL since it was persisting even after the production was brought down, said Vasudevan, Joint Chief Environmental Engineer at TNPCB.”We have issued the action to CPCL to adhere to the certain conditions and then after that, we have issued a direction to carry on the production to regularise,” he said.

The parameters mentioned above are monitored by both CPCL and TNPCB. The situation of the residents are unlikely to improve any time soon because there are no standards for odour pollution in India. “Residents have adapted to live in such conditions. Hence when there was an increase in the odour it was difficult for them to distinguish between whether to report or not” said Alibasha a tuition teacher at Thiruvottiyur.