The invention relates to a gas purification process and a
system, which solve the problem that the existing gas purification process is complex in process, large in waste water amount, high in production cost, poor in dedusting effect and low in
coal tar quality. The technical scheme is that
raw material coal is predried in a dryer and then sent to a high temperature
pyrolysis furnace for
pyrolysis, untreated gas containing ash and
coal tar and produced through
pyrolysis is sent to a high temperature
cyclone separator to remove ash in large particles, dedusting of the untreated gas after removing the ash in large particles is further carried out through a high temperature filter, gas is carried out
waste heat recovery through a
waste heat boiler after dedusting, the gas which exchanges heat to the temperature of 300-350 DEG C enters a chilling
tower and is contacted with
coal tar oil at the temperature of 40-80 DEG C in an adverse
current mode so as to conduct washing and cooling, the
coal tar contained in the gas enters the
coal tar oil and is discharged from a
tower bottom, the gas is washed and cooled to 40-100 DEG C at the
tower top to obtain clean gas, and the clean gas is sent to a
gas cabinet. The gas purification process and the device are simple, free of waste
discharge, good in gas dedusting effect, high in byproduct coal
tar quality and low in production cost.