Abstract:With the conditions closely imitating the practice production of the mill, the parameters of sulfate bagasse pulp acid pretreatment-ozone-hydrogen peroxide (AZP) short sequence total chlorine free (TCF) bleaching process were studied. The experimental results showed that the optimum process conditions were: pulp consistency 36%, pH value 2.0, ozone dosage 1.2%,ozone concentration 120 g/m3, reaction time 30 min, at room temperature for Z-stage; for P-stage pulp consistency 10%, the peroxidation dosage 3%, reaction time 120 min, reaction temperature 90℃, NaOH dosage 0.8%. The whiteness, viscosity and Kappa number of the bleached kraft bagasse pulp were 85.6%, 559 mL/g and 3.57, respectively.At the same time, compared with the traditional bleaching processes (OQP1P2, OP1ZP2), the pollution load was the lowest when AZP short sequence bleaching was applied, CODCr value was 760 mg/L, BOD5 was 90 mg/L, and chroma value was 680 C.U. |