CHENNAI: A five-member technical committee, which examined episodes of LPG odour in Manali and Tiruvottiyur that triggered panic among residents, hinted at Chennai Petroleum Corporation Limited (CPCL) being the source of the smell and recommended several measures including reducing use of high sulphur crude oil in the refinery.
The CPCL was also told to give details of crude feed with sulphur content on a daily basis to the Tamil Nadu Pollution Control Board (TNPCB).
The committee, comprising of scientists and representatives from the Central Pollution Control Board, IIT-Madras and Anna University, inspected CPCL and areas where complaints were reported and submitted its report with recommendations to the government on July 27.
Environment Minister Siva V Meyyanathan told TNIE, "The technical committee found CPCL to be the source of the odour and government is taking all steps to address the issue."
Additional Chief Secretary of Environment Department Supriya Sahu also said the committee has recommended CPCL to carry out several capacity building measures.
Some of the other key recommendations of the panel include reducing sour gas feed to sulphur recovery units (SRUs) to curtail feed of excess gas to the flaring system which is suspected to be the main source of the odour, steps to ensure enough incinerators are attached to SRUs to achieve sulphur recovery efficiency of 98.7% as per Hydrogen Sulfide (H2S) emission standards prescribed for the refinery by the Ministry of Environment as per a notification issued on March 18, 2008, and to furnish details of sulphur recovery efficiency with supporting documents to the TNPCB on a daily basis.
The refinery was also asked to ensure 0% opening of enriched acid gas valves to flare the acid gas by sending through SRU by providing adequate measures, burn excess hydrocarbons and acid gas in their furnaces/boilers without discharging them into the atmosphere, and utilise the regasified liquefied natural gas to the maximum extent possible.
TNPCB chairperson M Jayanthi and member secretary R Kannan had visited several localities in Tiruvottiyur and Manali areas where complaints of LPG odour were reported.
Jayanthi told TNIE, "The board is awaiting instructions from the State government after which necessary action will be initiated. The jurisdictional district environmental engineer also confirmed that the odour was being felt and we are planning to beef up our monitoring mechanism."
Environmental activist Nityanand Jayaraman said the culprit gases behind the odours are likely to be hydrogen sulphide and mercaptans which are present in high concentration in substandard crude oil. "H2S and mercaptans are potent neurotoxins that can damage children’s brain. If the committee has submitted its findings on July 27, why is TNPCB and State government not acting on it? Instead of returning this batch and using good quality crude, CPCL is being allowed to get away with it. This is criminal."
In an official response, CPCL told TNIE: "Subsequent to the pungent smell at Manali neighbourhood areas, CPCL has been following additional recommendations of TNPCB from July 21. CPCL is continuously working in close coordination with TNPCB to identify the root cause of these emissions."
Even two days back, several localities in Manali reported experiencing a strong LPG-like odour.
Technical committee report on Manali gas leak hints at Chennai Petroleum Corporation Limited (CPCL) being source of smell, recommends reducing use of high sulphur crude oil, among other steps