惰性气氛下准东煤Na/Ca释放特性的研究

基于准东煤中Na/Ca的赋存形态,采用管式加热炉研究了准东煤中Na/Ca在惰性气氛下的释放特性和形态转变。结果表明,水溶态Na_w在加热温度t ≤ 600℃时先转变成不可溶态Na_re,随着温度升高,不可溶态Na_re又重新转变成水溶态Na_w,当加热温度t > 800℃时,Na大量释放。酸溶态Ca_ac在加热温度t ≤ 700℃时先分解生成CaO并且与其他矿物组分反应转变成不可溶态Ca_re,随着温度升高,不可溶态Ca_re逐渐转变成酸溶态Ca_ac和水溶态Ca_w。相同温度条件下,Ca的释放率低于Na的释放率,少量酸溶态有机Ca随挥发分释放而以气相形式释放。

Release characteristics of Na/Ca in Zhundong coal under inert atmosphere

The release and transformation characteristics of Na/Ca in Zhundong coal under inert atmosphere were studied by using tubular heating furnace based on occurrence modes of Na/Ca containing species. It is found that water soluble Na_w firstly transfers to insoluble Na_re when the heating temperature is lower than 600℃. As the temperature increases, insoluble Na_re transfers back to water soluble Na_w. Large amount of Na releases when the temperature is higher than 800℃. Acid soluble Ca_ac firstly decomposes to CaO when the heating temperature is lower than 700℃, and CaO reacts with other minerals to form insoluble Ca_re. As the temperature increases, insoluble Ca_re transfers to acid soluble Ca_ac and water soluble Ca_w. At the same temperature, the release rate of Ca is lower than that of Na. Moreover, a little amount of acid soluble organic Ca will release when the volatile matter releases.