Degradation Characteristics of Paper Sludge and Changes of Heavy Metals in Soil

Chemical characteristics of paper sludge, degradation of the sludge in soil and generation, and changes of nitrogen and heavy metals in soil treated with the sludge were investigated. The results obtained was summarized as follows: 1. Degradation rate of paper sludge in soil was 19% at room temperature, and 28% at temperature after 12-weeks treatment. 2. T-C, T-N and the C/N ratio of the sludge in soil at room temperature were 15.5%, 0.22% and 71 respectively, and 14.5%, 0.24% and 60, respectively, at temperature after 12-week treatment. 3. genaration in soil treated with 1%, 3% and 5% of the sludge was 247mg/100g, 334mg/100g and 458mg/100g, respectively, at room temperature, and 385mg/100g, 550mg/100g and 618mg/100g, respectively, at incubation temperature after 12 weeks treatment. 4. Mineralization ratio of organic nitrogen in soil treated with 1%, 3% and 5% of the sludge was 8.7%, 13.4% and 16.2%, respectively, at temperature after 12-weeks treatment. 5. The amounts of DTPA-extractable Cu, Cd, Zn, Pb, and Cr in Soil treated with paper sludge were , , , , and , respectively. Mean while, those of extractable Cu, Cd, Zn, Pb, and Cr were , , , , and , respectively.