UPDATE 1-LyondellBasell says Houston refinery FCC shut

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HOUSTON, March 21 (Reuters) - LyondelBasell Industries Inc said on Friday the gasoline-producing fluidic catalytic cracking unit at its 270,000 barrel per day (bpd) Houston refinery would be shut for unplanned work through mid-April.

Refinery output will be reduced by an undisclosed amount while work is being done on the 100,000 bpd FCC, the company said in a statement.

The FCC's first-stage compressor shut down early on Wednesday morning and it could not be restarted, according to a notice the refinery filed with Texas pollution regulators.

Basell AF purchased Lyondell Chemical Co for $20 billion Dec. 20 to for LyondellBasell Industries. The company is owned by privately held Access Industries. (Reporting by Erwin Seba, Editing by Chizu Nomiyama)