Removal of recalcitrant organic matter from bleached kraft pulp effluents by ozonization

被引：0

作者：

Mounteer, Ann H. ^{[1
]}

Mokfienski, Jéssica Joy ^{[1
]}

Amorim, Fausto Rodrigues ^{[1
]}

机构：

[1] Universidade Federal de Viçosa, Viçosa, Brazil

来源：

O Papel (Brazil) | 2005年 / 66卷 / 03期

关键词：

Bleached pulp - Carbohydrates - Cellulose - Composition - Kraft pulp - Lignin - Ozone - Paper and pulp mills;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

The presence of recalcitrant dissolved organic matter in kraft pulp mill effluent treatment systems has lead to a search for alternative treatments to meet increasingly strict environmental permit limits. Ozone treatment is a promising technology for removal of recalcitrant organics and has been used mainly in tertiary treatment for mill effluent color and COD removal, but its recognized efficiency in increasing effluent biodegradability through increasing BOD, suggests its use in pretreatment before biological treatment. The object of this study was to characterize the chemical nature of the recalcitrant organic matter in eucalypt bleached kraft pulp effluents and to determine the potential for pre and post ozone application in removing this organic matter. Industrial bleached kraft pulp effluents were treated in a laboratory ozone reactor. Ozone dose (50-250 mg/L) and flowrate (3-20 mg/min) were varied to determine the pretreatment conditions resulting in the greatest increase in biodegradability (BOD/COD ratio) and these same conditions were also used in the post treatment for comparison. The original and treated effluents were separated into high and low molecular mass fractions and characterized by measuring their COD, BOD, TOC, AOX, color, carbohydrate and lignin contents to evaluate the effect of the chemical composition on ozone treatment efficiency. Pretreatment with 100 mgO3/L resulted in an increase in all parameters, especially their low molecular mass fractions. Biodegradability increased from 0,54 to 0,64, resulting from a combination of an increase in BOD and decrease in COD. Post treatment with ozone resulted in reduction all parameters, with greater removal of the high molecular mass fraction of COD, TOC and BOD. Degree of chlorination (AOC/TOC ratio) of the dissolved organic matter was unaffected by either pre or post treatment. Ozone pretreatment showed great potential for transforming recalcitrant organic matter into biodegradable matter. We are currently investigating how this potential can be translated into increased biological treatment efficient.

引用

页码：64 / 70