The rate of nitrogen release during high pressure coal pyrolysis

The particle porosity, mass of volatiles and nitrogen release has been described in form of multireaction kinetic equations for the pyrolysis at 0.1 MPa and 1 MPa pressure. It has been found that for higher pressure the final char porosity decreases, however the char porous structure is almost independent of pressure. Both at 0.1 MPa and 1 MPa the release of volatile precedes the coal particle porosity evolution. The variation of nitrogen content in char does not depend on pressure for the first devolatilization stage (short time), while for the final stage of devolatilization higher nitrogen content in char was observed for enhanced pressure.