Royal Dutch Shell is closing an office near Pittsburgh next summer, but that won’t affect a pending decision on whether to build a major petrochemical plant in Beaver County. Shell spokeswoman Kimberly Windon tells the Pittsburgh Tribune-Review that most of the 180 workers at its Franklin Park office who are involved in gas and oil drilling will be moved to Houston, the company’s U.S. headquarters. She says the decision won’t affect ongoing efforts to redevelop a former zinc plant for possible use as a petrochemical cracker plant in Potter Township. Shell hasn’t formally committed to the project, but has spent millions on the site.