Fault tree analysis report for Combustion Engineering, Inc. coal-gasification process-development unit in support of the Combustion Engineering/Gulf States Utilities Coal-Gasification Demonstration Plant

While work on the PDU safety tree was in progress, C-E's contract with the DOE was curtailed. Under the reduced work scope, safety and reliability fault trees for the PDU were constructed; however, the verification and analysis of these trees could not be completed. In addition, no work was done on the risk and reliability assessment of the demonstration plant design. Detailed fault trees with probability and failure rate calculations were generated for the events: (1) Fatality due to Explosion, Fire, Toxic Release or Asphyxiation at the PDU Coal Gasification Process; and (2) Loss of Availability of the PDU. The fault trees for the PDU were synthesized by Design Sciences, Inc. The trees were then subjected to multiple reviews by Combustion Engineering. The steps involved in hazard identification and evaluation, fault tree generation, probability assessment, and design alteration are presented in the main body of this report. The fault trees, cut sets, failure rate data and unavailability calculations are included as attachments to this report. Although both safety and reliability trees have been constructed for the PDU, the verification and analysis of these trees were not completed as a result of the curtailment of the demonstration plant project. Certain itemsmore » not completed for the PDU risk and reliability assessment are listed.« less