The destructive distillation of bituminous coal,done in the absence of air in order to obtain coke and other fractions having a greater percentage of carbon than the original material.

• 碳化作用烟煤的分解蒸馏，在没有空气的条件下进行，为得到比最初的原料所含碳的百分比大得多的焦煤以及其它馏分