A combustion system capable of self-sustaining, unpiloted coal burning at thermal outputs as low as 500 W and as high as 50 kW has been designed and constructed at Washington University in St. Louis
https://www.powershow.com/view4/5626b7-YzNhM/A_combustion_system_capable_of_self-sustaining_unpiloted_coal_burning_at_thermal_outputs_as_low_as_500_W_and_as_high_as_50_kW_has_been_designed_and_constructed_at_Washington_University_in_St_Louis_powerpoint_ppt_presentation
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