The invention discloses an external-heated and
solid heat carrier combined rotary dry-
distillation method and device. The method comprises the steps of mixing a
heat carrier and dried / preheated raw
coal, and enabling a mixture of the
heat carrier and the dried / preheated raw
coal to be subjected to
dry distillation in a
dry distillation furnace, so as to generate hot semicoke and
coal gas, wherein one part of the hot semicoke is a semicoke product, one part of the hot semicoke is hot
coke granules, and the hot
coke granules serve as the heat carrier and are applied to
coal gas dedusting after the hot
coke granules are heated;
smoke generated during semicoke heating is used for
drying and preheating raw coal. The device comprises a raw coal preheating and
drying oven, a semicoke
heating furnace and the
dry distillation furnace, wherein the raw coal preheating and
drying oven and the semicoke
heating furnace are located above the dry
distillation furnace, and a material outlet of the raw coal preheating and drying oven and a material outlet of the semicoke
heating furnace are communicated with a material inlet of the dry
distillation furnace; the dry distillation furnace and the semicoke heating furnace are communicated by a hot coke granule circulating and conveying
system; the dry distillation furnace preferably is an external-heated dry distillation furnace. The method and the device, disclosed by the invention, have the advantages that the
thermal efficiency is high, the calorific value of the
coal gas is high, the dust content is low, and the yield is large; the device is compact in structure and small in floor area.