Reliability Analysis of a Fluidized-Bed Boiler for a Coal-Fueled Power Plant

This is a reliability study of an experimental fluidized-bed boiler for a coal-fueled plant. The study determined the major contributors to plant outage in terms of equipment failure and plant management. The major problems associated with fluidized-bed development and operation are related to a plant startup and research environment rather than to equipment reliability. Consequently, operations of this experimental facility were continued on the optimistic note that future plant performance could be appreciably improved by modifying operating practices to minimize plant outage attributed to: 1. Prolonged equipment maintenance due to the lack of readily available spare parts. 2. Delayed startup due to performing non-critical preventive maintenance. 3. Minimal repair activity performed on the second and third work shifts or for an entire weekend. 4. Delayed startups after the completion of repairs until a subsequent shift or until the end of a weekend. A clearer understanding of existing system and equipment problems enabled engineering to improve plant availability by: 1. Minimizing coal fines plugging of feed needles by increasing needle diameters from 1.5 to 2.0 inches. 2. Relieving excessive strain on the fuel handling system by eliminating stop and start operation of the coal bucket elevators under full load. 3. Eliminating dependence on outside plant services and facilities sharing host-plant feedwater.