An analytical equation to predict accurately Vroom's H-factor during c
hemical pulping has been developed from first principles. The equation
takes into account the variation in entering liquor temperature. The
heating rate from the entering temperature to the cooking temperature
is assumed to be linear This assumption results in a nonlinear relativ
e reaction rate. The use of the entering liquor temperature as an inpu
t variable in conjunction with the nonlinear relative reaction rate al
lows this equation to be used in conjunction with modern cooking schem
es like MCC and RDH.