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Hydrogen Safety and Loss Prevention in Industries Sergey Dorofeev. Introduction of FM Global. FM Global. Commercial and Industrial Property Insurance - A Specialty Company “Majority of Loss is Preventable” - Through Research/Engineering Mutual Ownership. FM Global - Numbers.
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Hydrogen Safety and Loss Prevention in IndustriesSergey Dorofeev
FM Global Commercial and Industrial Property Insurance - A Specialty Company “Majority of Loss is Preventable” - Through Research/Engineering Mutual Ownership
FM Global - Numbers • Fortune 541 • > 5,000 employees • 1,800 engineers • 39 offices worldwide • Research: > 110 scientists and engineers (>50 Ph.D.)
FM Global Losses FM Global: Loss prevention engineering in fire, equipment, explosions and natural hazards
Hydrogen: old and new characters • Safety of hydrogen as an energy carrier • Hydrogen fueled vehicles • Refueling infrastructure • Distributed / renewable energy • … • New character
Hydrogen: old and new characters • Hydrogen safety & loss prevention in industries • Nuclear • H2 cooled generators • H2as a process chemical • Aerospace • … • Old character
Hydrogen: old and new characters • Hydrogen safety & loss prevention in industries • Nuclear • H2 cooled generators • H2as a process chemical • Aerospace • … • Old character
Nuclear • Accidents at NPP • Core-melt down accidents • Radiolysis gas explosions • Extensive studies since 1970that BNL, SNL, McGill, KI, FZK (KIT), … • Physical phenomena well understood • Three Mile Island NPP
Nuclear • Severe core melt down accidents • Three Mile Island • Fukushima Dai Ichi • H2 generation from melted core – steam reaction • Hydrogen mixing and explosion in a containment / reactor building
P, bar Slow subsonic flames Fast supersonic flames Detonations Hydrogen explosions • Variety of explosions regimes • Flame acceleration • DDT • Pressure loads depend on explosion regime • Confined • Unconfined
Explosion limits H2-air-steam mixtures at 450K, 2bar Room size L = 2 m Room size L = 0.5 m
Pressure loads • H2 deflagration in VVER-1000 containment B0X code, KI • BWR Mark I reactor building not designed for deflagration loads
Radiolysis gas explosions • Two accidents at BWR NPPs with DN15 piping (2001) • Hamaoka-1 NPP • Brunsbuettel KKB H2-O2-steam at T=560K and P=70 bar M. Kuznetsov
Radiolysis gas explosions • Pipe fracture Brunsbuettel KKB At BWR operating conditions PCJ= 806 bar M. Kuznetsov Hamaoka-1 NPP
Safety & loss prevention – nuclear • Hydrogen explosions in PWRs • Containment design • Hydrogen recombination • Local detonations difficult to avoid at high H2 release rates • Risk understood and accepted… Is problem solved? • Radiolysis gas • Temperature control
Hydrogen: old and new characters • Hydrogen safety & loss prevention in industries • Nuclear • H2 cooled generators • H2as a process chemical • Aerospace • … • Old character
Hydrogen cooled generators • Electric power generators produce large amounts of heat • Hydrogen is nearly perfect cooling gas • Generator is filled with H2 • H2 is sealed • System to purge H2 at shutdowns • Not all generators are H2 - cooled
Hydrogen oil seal system • Hazard combination • H2 explosion • Lube oil fire • Oil pressure to be maintained • Hydrogen to be replenished • Systems are complicated
Things happen • American Electric Power • Tank relief valve failure • Damage to building and generator
Things happen • American Electric Power • Detonation?
Things happen • Georgia Power • Improper purge procedures
Things happen • Georgia Power • Huge damage to building and generator
Things happen • Tampa Electric power • Improper purge procedures
Generators: Explosion hazards • Failure of seal oil system – H2 leak out into turbine hall • Component failure could lead to a release • A leak of the oil reservoir could lead to a fire and system failure • Ignition and explosion – damage to building, generator, nearby equipment
Generators: Loss prevention • Redundant pumps: AC and DC (with properly sized battery bank). • A routine hydrogen purge and fill procedure • timed tested and documented • Appropriate system alarms (H2 pressure and purity, etc.)
Generators: Explosion protection • Vents for vacuum tanks, extractors and relief devices routed outside • Welded hydrogen piping routed out of way of potential impact damage • Properly rated electrical equipment near generator. Class 1 Division 2 • At least 15 m clearance between hydrogen system and any electrical areas, air intakes, etc.
Hydrogen: old and new characters • Hydrogen safety & loss prevention in industries • Nuclear • H2 cooled generators • H2as a process chemical • Aerospace • … • Old character
Hydrogen as a process chemical • Experienced handling of hydrogen • Hydrogen production • Chemical plants, refineries,… • Specialty industries, safety culture, trained personal, procedures… VS • Inexperienced, new to hydrogen, or lack of safety culture…
Hydrogen as a process chemical • Experienced handling of hydrogen • Hydrogen production • Chemical plants, refineries,… • Specialty industries, safety culture, trained personal, procedures… VS • Inexperienced, new to hydrogen, or lack of safety culture…
Hydrogen atmosphere furnaces • Hoeganaes Corporation: Gallatin, TN CSB report No. 2011-4-I-TN
Process • Hoeganaesis worldwide producer of atomized steel and iron powders • Coarse iron powder is processed in annealing hydrogen atmosphere furnaces to make the iron more ductile • Hydrogen piping is located in a trench under the floor and covered by metal plates
Hydrogen Explosion • MAY 27, 2011 (THREE FATALITIES, TWO INJURIES) • A hissing noise near band furnace #1 identified as a gas leak • Presumed that the leak was nitrogen (same trench as H2) • Needed machinery to lift trench covers CSB report No. 2011-4-I-TN
Hydrogen Explosion • Forklift used • Friction created sparks, powerful explosion • Iron dust fires CSB report No. 2011-4-I-TN
The cause • Trench: N2, H2, vent pipes, and a drain for the cooling water • Pipe corrosion • Standards notfollowed • ASME B31.3 • CGA G-5.4 • NFPA 2, 55 CSB report No. 2011-4-I-TN
Loss prevention – hydrogen atmosphere furnace • Ambient conditions around process pipes as per ASTM • focus on environments that can create physical stresses in piping • Controlling and mitigating unauthorized discharges • Procedure to inspect piping • Protocol to mitigate gas leaks • Investigating a leak by testing the atmosphere for concentrations of explosive gas
Safety & loss prevention summary • Common accident prevention measures • Controlling H2 mixture composition • Controlling unintended discharge • Monitoring and inspecting (piping, connections, vessels, detectors,…) • Redundant safety systems • Operation procedures • Rated electrical equipment • Safety / separation distances
Safety & loss prevention summary • Common explosion protection measures • Venting high pressure vessels • Mitigating unintended discharge (recombination, ventilation…) • Explosion venting • Damage limiting construction • Safety / separation distances • Old traditional approaches…
Safety & loss prevention summary • Most accidents are preventable through research and engineering • Identify hazards and risk • Develop loss prevention and safety solutions • Accidents still occur • Improvement of engineering solutions • Awareness • Information • Education • Training
New hydrogen • We need advanced safety culture and new engineering solutions • Extreme operating conditions • New technologies • High system complexity • Inexperienced operators • …
Issues • Further refinement needed • Standardization • Education and training • Emergency response • New engineering solutions • Mitigating unintended hydrogen discharge • Gaseous, Cryogenic, Liquid H2 • Explosion venting • Explosion suppression / isolation? • …