The stock slipped 5.04 per cent to settle at Rs 191.30 on BSE. During the day, it lost 5.6 per cent to Rs 190.15.
At NSE, shares of the company went down by 5.14 per cent to Rs 191.75.
The company's market valuation fell by Rs 150.32 crore to Rs 2,848.68 crore.
In terms of volume, 1.53 lakh shares of the company changed hands at BSE and over 8 lakh shares were traded at NSE during the day.
CPCL, a subsidiary of Indian Oil Corp (IOC), is however operating smaller 1 million tonnes a year Nagapattniam unit normally.