Abstrait

Leaching Behavior Of Oil In Cement-Based Solidified Oily Sludge

QU Cheng-tun, CHEN Jie-rong, Wang Xin-qiang, Yan Yong-li

Solidification of hazardous waste using Portland cement has been and is currently being used in solidification technology, but knowledge of the exact leaching behavior of contaminants is limited. In this study, the effects of parameters including time, temperature and the cement/sludge ratio on the diffusion behavior of oil after the solidification of oily sludge were investigated by using extraction and UV spectrophotometer. These experimental results indicated that the quantity of oil diffusion varies from 1.18 at 24 hours to 3.48 mg/L at 72 hours. The amplitude of oil diffusion within 72 hours is the most distinct and thereafter, the variation becomes slower. The diffusion quantity enhances from 2.01 to 2.77 mg/L with the increment of temperature under the range of 298~308K. The trend displays flat when the temperature is beyond 308K. The amount of oil diffusion reduces from 3.82 to 2.80 mg/L with the increasing of the cement/sludge ratio under the range of 1.0 ~1.8. The diffusion quantity reaches 2.69mg/L at 120 hours after adding reinforcing agent of melamine resin, which is lower than without reinforcing agent. The diffusion quantity could arrive at 5mg/L through 120 hours, which meets the demands requested by national first order dispatching in China.