Experimental Study of the Pyrolysis of Pure and Fire Retarded Cellulose

摘要

The pyrolysis of pure and fire retarded bulk cellulose samples in a nitrogen atmosphere is studied. The study is directed toward determining the effects of the solid phase fire retardant (sodium hydroxide) on the burning of cellulose. The material property of pure and fire retarded cellulose which most directly affects its burning behavior, the heat of gasification, is measured by using a specially designed pyrolyzing chamber. Theoretical results are obtained for a one-dimensional pyrolysis wave propagating into cellulose by using a finite-difference calculation. The experimental data show that sodium hydroxide acts as a catalyst in the pyrolysis of cellulose. Its addition leads to decreases in the heat of gasification and the mass fraction of noncombustible volatiles in the total volatiles and to increases in stoichiometric ratio and the heat of combustion of combustible volatiles, and thereby has a dual effect on cellulose burning.