The oxygen production had to be stopped temporarily following a technical snag in the cold box at the oxygen plant on May 14.
In a statement shared on the micro-blogging site on Sunday, Sterlite Copper said, "efforts to resume production at our oxygen plant are progressing".
The company's environmental violations very quickly proved impossible to ignore and drew sharp censure not just from local activists but also international investors and institutions.
Sterlite protests Day 3 UPDATES: Vedanta founder Anil Agarwal says he is 'in pain' over Thoothukudi deaths
On Wednesday late night, a youngster who was under treatment succumbed to injuries taking the toll to 13.
Tamil Nadu: Madras High Court stays construction of new copper smelter by Sterlite industries in Thoothukudi
The stay comes a day after 11 people were killed and 20 others grievously injured after police reportedly opened fire multiple times against anti-Sterlite protesters in Thoothukudi on Tuesday.
Demonstrations against the copper plant, one of India's biggest, have been going on for more than three months, with protesters alleging that it is a major source of pollution and risk to fisheries.
Sterlite protests: Tamil Nadu Government says Tuticorin police were forced to open fire on protestors
About 20,000 people took out a procession towards the district collectorate and the copper plant with the intention of picketing them, demanding for its permanent closure, and resorted to violence.
Death toll in Sterlite protest rises to 11; Retired judge to inquire into Thoothukudi police shoot-out
With the situation still tense, Tamil Nadu CM Palaniswami has defended the police saying the cops resorted to firing only because the protestors started torching vehicles and pelting stones.
Tamil Nadu Pollution Control Board refuses to renew consent for Thoothukudi Sterlite plant, smelting operations shut down indefinitely
The scheduled maintenance activities were supposed to be for a period of approximately 15 days, it is now likely to be extended.
'Ban Sterlite': Thousands of protesters hit the streets demanding closure of copper plant in Thoothukudi
Local residents argue that the existing smelter has been polluting their water and air since it was established in 1996.
British Tamils protest outside Vedanta chief Anil Agarwal's London home against Tuticorin Sterlite Copper Plant
Carrying traditional Tamil parai drums, dozens of protesters gathered outside the Mayfair home of the Vedanta chief to coincide with major demonstrations in Thoothukudi in Tamil Nadu yesterday.