PURPOSE: To improve the efficiency of oil recovery, by forming a rapidly heating zone at the upper part of a dry distillation zone and simultaneously introducing a low-temperature gas into the upper part of the rapidly heating zone to properly keep the temperature of a preheating zone.
CONSTITUTION: In the dry distillation of oil shale comprising blowing a dry distilled gas into a layer of oil shale particles which are preheated in a preheating zone and descend within a vertical furnace while keeping the temperature of the dry distillation zone at 400W500°C, a gas for dry distillation, which is kept at a temp. that is 300W500°C higher than the dry distillation temperature, is introduced into the upper part of the dry distillation zone to form a rapidly heating zone, whereby pores within oil shale are enlarged to make holes through which distilled oil is passed. Simultaneously, a low-temperature gas is introduced into the upper part of the rapidly heating zone to properly keep the temperature of the preheating zone and to lower the temperature of waste gas.
MORI TAKASHI
KATAYAMA TSUTOMU
MITSUIDA KAZUTAKA
