Investigation on high yield chemimechanical pulping of bagasse (CMP-CTMP-APMP)

Abstract

In order to investigate the possibility of utilizing bagasse in high yield pulping, CMP and CTMP pulp from bagasse was compared.APMP pulping process was also investigated. Bagasse fiber length, diameter, lumen diameter and cell wall thickness was measured at 1166mm, 19.63 mLm,7.47 mLm, and 6.09 mLm respectively. Chemical composition was as follow: cellulose 553 %, lignin 20.5 %, ash 1.98% and extractive 2.9 %.The results and comparison of CMP and CTMP pulp are as follow: CTMP pulp yield was 3-4% higher than CMP pulp and the highest CTMP pulp at 80.7% was obtained at 15% NaOH application and 15 minutes chemical treatment time.Breaking length of both pulp was almost equal, but the burst index of CMP pulp was higher and the tear index was lower than CTMP. The highest breaking length of 3.85Kmwas obtained at 15% NaOH and 10 minutes, highest burst index of 4.81 KPa.m2/grat 20% NaOH and 20 minutes and highest tear index at 6.87 mN.m2/grat 15% NaOH and 15 minutes treatment time. Various treatments in APMP pulping reveald the following results: - Two stage pulping yield was almost 6% higher than one stage pulping and addition of H2O2 did not significant improve the yield.- The highest breaking length was related and two stage pulping. But addition of H2O2 in last stage and the lowest breaking length was related and two stage pulping with split application both NaOH and H202.- Even though two stage pulping with the addition of H2O2 in one stage produced highest burst index, but lowest burst index was with the CMP pulps.- Addition of DTPA produced highest brightness and opacity.

Keywords

• chemimechanical pulping
• Bagasse
• CMP
• CTMP
• APMP