Nov. 7 (Bloomberg) -- BP Plc plans to resume operations today at a cracking unit at its Texas City, Texas, refinery, the third-largest in the continental U.S.

Emissions associated with the startup of the so-called ultracracking unit will begin today and last through Nov. 19, according to a BP filing with the Texas Commission on Environmental Quality. The unit takes heavier oil products and uses heat and hydrogen to convert them into more valuable fuels such as diesel.

The startup has been delayed. The refinery has a capacity of 470,000 barrels a day, according to data compiled by Bloomberg.

Last Updated: November 7, 2009 07:05 EST