As disengager contains a large volumne space in which the oil vapor flows at lower velocity and resides for a longer time,the over-cracking of oil vapor occurs and the liquid droplets in oil vapor and catalyst particles tend to deposit on the internal wall of disengager to form coke.

To get clean hydrogen-rich gas from biomass,an innovational process of hydrogen production by pyrolysis and twice decomposition was introduced,which realized the deep conversion of hydrocarbons to decrease tar sharply and improve hydrogen yield.

The rush, recoil and secondary break of the chimney in the process of collapse, which is demolished using directional blasting technique, is analyzed in detail in this paper, and the calculation formula are developed.