By OGJ editors
HOUSTON, Feb. 15 -- ConocoPhillips announced two senior leadership changes.

Robert Herman, currently president, Europe refining, marketing, and transportation, will become vice-president, health, safety, and environment. He succeeds Bob Ridge, who will retire after more than 31 years of service.

Larry Ziemba, currently president, US refining, will become president, global refining. In this expanded role, Ziemba will assume responsibility for all of ConocoPhillips’s worldwide refining operations.