本文选取三个煤样,在滴管炉(DTF)上制取了五种焦样,应用差示扫描量热(DSC)法对其在70~500℃的比热容进行了测定,并与根据经典煤焦比热模型计算得到的数值进行了比较。实验煤焦比热容的实验值与计算值都随温度升高单调增加,从70℃的0.9 kJ/(kg·K)左右增大到500℃时的1.4~1.7 kJ/(kg·K)左右,一般实验值要略大于理论值。1100℃下的焦样,比热容均比1300℃下的焦样要大,且原煤中挥发分含量V(daf)越高,对应的两个热解温度水平下的焦样的比热值相差越大。
Three kinds of raw coals are selected,and five kinds of coal-char samples are obtained in a Drop Tube Furnace(DTF).The values of their specific heat in the range of 70~500℃are determined by applying DSC,and are compared with the values calculated by the classic theoretical models. Below 500℃,the values of specific heat of char samples monotonically increase from around 0.9 kJ/(kg·K) to 1.4~1.7 kJ/(kg·K) with the same trend of the theoretical data that is slightly smaller. The values of specific heat of chars prepared at 1100℃are all higher than that of chars prepared at 1300℃.The volatile content V_(daf) of raw coals influences the difference in the values of specific heat between chars prepared at different temperature levels.