Gao Xingbao, Ji Bingjing, Yan Dahai, Huang Qifei, Zhu Xuemei
1 State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China.
2 School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing, China.
Waste Manag Res. 2017 Apr;35(4):437-443. doi: 10.1177/0734242X16677078. Epub 2016 Dec 5.
Degradation of polychlorinated dibenzo- p-dioxins and dibenzofurans in municipal solid waste incinerator fly ash is beneficial to its risk control. Fly ash was treated in a full-scale thermal degradation system (capacity 1 t d) to remove polychlorinated dibenzo- p-dioxins and dibenzofurans. Apart from the confirmation of the polychlorinated dibenzo- p-dioxin and dibenzofuran decomposition efficiency, we focused on two major issues that are the major obstacles for commercialising this decomposition technology in China, desorption and regeneration of dioxins and control of secondary air pollution. The toxic equivalent quantity values of polychlorinated dibenzo- p-dioxins and dibenzofurans decreased to <6 ng kg and the detoxification rate was ⩾97% after treatment for 1 h at 400 °C under oxygen-deficient conditions. About 8.49% of the polychlorinated dibenzo- p-dioxins and dibenzofurans in toxic equivalent quantity (TEQ) of the original fly ash were desorbed or regenerated. The extreme high polychlorinated dibenzo- p-dioxin and dibenzofuran levels and dibenzo- p-dioxin and dibenzofuran congener profiles in the dust of the flue gas showed that desorption was the main reason, rather than de novo synthesis of polychlorinated dibenzo- p-dioxins and dibenzofurans in the exhaust pipe. Degradation furnace flue gas was introduced to the municipal solid waste incinerator economiser, and then co-processed in the air pollution control system. The degradation furnace released relatively large amounts of cadmium, lead and polychlorinated dibenzo- p-dioxins and dibenzofurans compared with the municipal solid waste incinerator, but the amounts emitted to the atmosphere did not exceed the Chinese national emission limits. Thermal degradation can therefore be used as a polychlorinated dibenzo- p-dioxin and dibenzofuran abatement method for municipal solid waste incinerator source in China.
城市生活垃圾焚烧飞灰中多氯代二苯并 - 对 - 二噁英和二苯并呋喃的降解有利于其风险控制。飞灰在一个规模为1吨/天的全尺寸热降解系统中进行处理，以去除多氯代二苯并 - 对 - 二噁英和二苯并呋喃。除了确认多氯代二苯并 - 对 - 二噁英和二苯并呋喃的分解效率外，我们还关注了两个主要问题，这两个问题是该分解技术在中国商业化的主要障碍，即二噁英的解吸和再生以及二次空气污染的控制。在缺氧条件下于400℃处理1小时后，多氯代二苯并 - 对 - 二噁英和二苯并呋喃的毒性当量值降至<6纳克/千克，解毒率⩾97%。原始飞灰中约8.49%的多氯代二苯并 - 对 - 二噁英和二苯并呋喃的毒性当量（TEQ）被解吸或再生。烟气粉尘中极高的多氯代二苯并 - 对 - 二噁英和二苯并呋喃水平以及二苯并 - 对 - 二噁英和二苯并呋喃同系物谱表明，解吸是主要原因，而非排气管中多氯代二苯并 - 对 - 二噁英和二苯并呋喃的从头合成。降解炉烟气被引入城市生活垃圾焚烧炉省煤器，然后在空气污染控制系统中进行协同处理。与城市生活垃圾焚烧炉相比，降解炉释放出相对大量的镉、铅以及多氯代二苯并 - 对 - 二噁英和二苯并呋喃，但排放到大气中的量未超过中国国家排放标准。因此，热降解可作为中国城市生活垃圾焚烧源多氯代二苯并 - 对 - 二噁英和二苯并呋喃的减排方法。
