EPJ Web of Conferences, open-access proceedings in physics and related sciences

The process of anthracite and its semi-coke combustion in the presence of 5 wt.% (in terms of dry salt) additives of copper salts Cu(NO₃)₂ and Cu(CH₃COO)₂ was studied. The activating additives were introduced by an incipient wetness procedure. The ignition and combustion parameters for coal samples were examined in the combustion chamber at the heating medium temperatures (T_g) of 600–800 °C. The composition of the gaseous combustion products was controlled using an on-line gas analyzer. The fuel modification with copper salts was found to reduce the ignition delay time on average, along with a drop in the minimum ignition temperature T_min by 138–277 °C. With an increase in T_g temperature, a significant reduction in the ignition delay time for the anthracite and semi-coke samples (by a factor of 6.7) was observed. The maximum difference in the ignition delay time between the original and modified samples of anthracite (ΔT_i = 5.5 s) and semi-coke (ΔT_i = 5.4 s) was recorded at a T_g temperature of 600 °C in the case of Cu(CH₃COO)₂. The emergence of micro-explosions was detected at an early stage of combustion via high-speed video imaging for samples modified by copper acetate. According to the on-line gas analysis data, the addition of copper salts permits one to reduce the volume of CO formed by 40% on average, providing complete oxidation of the fuel to CO₂. It was shown that the introduction of additives promoted the reduction in the NO_x emissions during the combustion of the anthracite and semi-coke samples.

MATEC Web of Conferences, open access proceedings in Materials science, Engineering and Chemistry