Safety Matters for Demonstration of VAM-RAB Technology at Mandalong Gary Bowman Manager of Electrical Engineering May 2014 www.centennialcoal.com.au
Outline Ø Background to Project Ø Project Safety Integration Ø Safety Process and Features Ø Outcomes and Learnings Ø Where to from here 2
Background Ø Centennial sought a means of reducing dilute methane in ventilation air (VAM) Ø Worked with Corky s Sustainable Energy to demonstrate their Ventilation Air Methane Regenerative Afterburner VAM-RAB Ø Funding was granted from the NSW Government Clean Coal Fund to demonstrate a 10m3/sec unit Ø Corky s had a technical design, focus turned to making it a safe design, acceptable to the Mine and its Regulators 3
Acknowledgement and Disclaimer Funded by Coal Innovation NSW through the Clean Coal Fund, which is administered by the Minister for Mineral Resources Any views expressed herein do not necessarily reflect the views of Coal Innovation NSW or the NSW Government 4
Safety Integration Ø Designed using CHAIR (Construction Project) Ø Onsite move from CHAIR to MDG1010 for acceptability for mine site perspective Ø Independent HAZOP review 5
Complex Design and Safety Requirements Safety sits above V model process manage safety in the design Concept of Verification Operation and AS 61508 Operations and Maintenance AS IEC 61511 Validation Safety Requirements Project definition Requirements and Architecture Detailed Design Implementation System Verification and Validation Integration Test, and Verification Project Test & Integration Risk Assessments 6
Safety Design Ø 196 Hazards Identified (Chair 1) Ø 2 only managed by SIL (safety critical) deflagration caused by uncontrolled machine operation or uncontrolled fuel source Ø 192 managed by Australia Standards/MDG s and risk assessment controls Ø R&D project/first-of-type Centennial had specific safety and environmental requirements; Ø Engagement of mine regulators who had specific views and thoughts. 7
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Key Design Aspects Key design aspects added during the risk/design process: Ø Considered return air to the inlet reversal valves as part of the mines return airway (We considered the machine to be directly coupled to the mine) Ø Deflagration internal pressure detection, over temperature detection Ø Inlet fuel limits exceeded Ø Response time to methane event How quickly can the plant isolate from the Mine; Underground monitoring, multiple independent layers of protection. 9
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Outcomes Ø Both the Safety Requirement Specification and the Verification and Validation plan were peer reviewed to confirm achieved SIL Ø Hazardous area assessment Audited to confirm installation was compliant to the hazardous area zoning Ø Electrical installation standards audited- AS3000, AS3007, IS audits and Arc flash Ø Mechanical installation standards audited some MDGs required tailoring Ø Class 3 Gas Appliance Approval for burners 11
Learnings Commissioning of this type of plant very difficult onsite Ø First of type so the predicted operational parameters agreed upon in the commissioning risk assessment were not practical Ø The redefining of operational limits managed under the Mine Change Management System which required review of the risk assessment and effect of safety functionality. MUST HAVE Robust Change Management Process. Ø Key hold points established in the commissioning process this included review of all relevant risk assessment actions and completion of audits before progressing to each stage eg, Pre Power, Powered, Cold Commissioning, Hot commissioning (Heating with Burners, Simulated VAM and Mine VAM) Ø Comfortable with design team 12
Where to From Here Ø Complete VAM Simulation trial Ø Connect to Mine ventilation system for 12 months and final evaluation 13
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