State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
Waste Manag. 2012 Jul;32(7):1453-8. doi: 10.1016/j.wasman.2012.03.007. Epub 2012 Apr 3.
Nitrogen containing compounds such as ammonia, urea and amines can effectively inhibit the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Sewage sludge accumulates both sulfur and nitrogen during wastewater treatment so it could be used to reduce PCDD/Fs formation. Indeed, it is observed in this study that the gas evolving from the sludge drying process can significantly suppress chlorobenzene (CBz) and PCDD/Fs formation from fly ash collected from a hospital waste incinerator. For instance, the reduction of hexachlorobenzene (HxCBz) and PCDD/Fs amount was 92.1% and 78.7%, respectively, when the drying gas evolving from 2g sludge flew through 2g fly ash. These tests were conducted in the frame of projects devoted to hospital waste incineration. The disposal technology for hospital waste (HW), developed in this institute, features rotary kiln pyrolysis combined with post-combustion followed by flue gas cleaning. Hence, some preliminary tests were devoted to investigate dioxins suppression by co-pyrolysis and co-combustion of polyvinyl chloride (PVC) and sludge in lab scale. More experimental research will be conducted to appropriately assess these effects of sludge on PCDD/Fs emissions during co-pyrolysis/combustion of HW and sludge.
含氮化合物，如氨、尿素和胺，可有效抑制多氯二苯并对二恶英和多氯二苯并呋喃（PCDD/Fs）的形成。污水污泥在处理废水的过程中会积累硫和氮，因此可以用于减少 PCDD/Fs 的形成。事实上，本研究观察到，从医院废物焚烧炉收集的飞灰中，从污泥干燥过程中释放出的气体可以显著抑制氯苯（CBz）和 PCDD/Fs 的形成。例如，当 2g 污泥释放的干燥气体通过 2g 飞灰时，六氯苯（HxCBz）和 PCDD/Fs 的减少量分别为 92.1%和 78.7%。这些测试是在专门针对医院废物焚烧的项目框架内进行的。本研究所开发的医院废物（HW）处理技术采用回转窑热解与后燃烧相结合，然后进行烟气净化。因此，进行了一些初步测试，以研究聚氯乙烯（PVC）和污泥在实验室规模的共热解和共燃烧过程中对二恶英的抑制作用。将进行更多的实验研究，以适当评估污泥在 HW 和污泥共热解/燃烧过程中对 PCDD/Fs 排放的影响。
