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The methane released from the coal combines with the air to form a very dangerous explosive mixture, which will be aggravated by the combustible gases of CO and H2 produced from the coal smoldering in coal mine. In this work, the effect of binary CO-H2 mixtures on methane explosion limits is investigated, and the inhibitory effect of N2 dilution on mixed combustible gases is analyzed via experiments and simulations subsequently. The methane explosion limits under different operating conditions are studied using a standard 20-L spherical chamber. The addition of the binary gas of CO-H2 mixtures exhibit a reduction for LEL and UEL of methane explosions, and remarkably enhance methane explosion risk. Moreover, the addition of binary gas mixture leads to a larger expansion range of the explosion triangle, compared to single CO conditions. In the simulations, the sensitivity of dominant elementary reactions on the H, O, and OH free radicals are analyzed based on the GRI mech 3.0 mechanisms. The inerting effect of N2 in CH4/CO/H2 component system is manifested in the combustion reaction kinetics of R53, R98, and R158, showing a significant inhibitory effect on the generation of these radicals during explosive process. The research results are helpful to understand the hazards of methane explosion in the coal fire area, and have certain guidance for the treatment of methane explosion in coal mine.

With the recent announcement of a joint goal among federal agencies to deploy 30 GW of offshore wind capacity by 2030 and the target for the Bureau of Ocean Energy Management (BOEM) to approve the Construction and Operations Plans of at least 16 offshore wind farms by 2025, the US offshore wind industry appears to be on the cusp of a major expansion. However, a literature review of the history and current state of the US offshore wind industry indicates that resource constraints within the BOEM and obstacles posed by the complex regulatory process could prevent the industry from reaching its full potential. A critical analysis was conducted on information and data collected from primary and secondary sources to propose strategies for mitigating and avoiding this regulatory turbulence. This paper concludes that BOEM must increase its bandwidth and accelerate the rate of offshore wind project review and approval by pursuing resource augmentation measures and opportunities to introduce efficiencies into its regulatory approach.