城市生活垃圾焚烧飞灰对CO2的固定

Sequestration of CO_2 using municipal solid waste incinerator fly ash

为无害化处理焚烧飞灰,并实现CO2减排,利用中国城市生活垃圾焚烧飞灰作为吸附剂,固定CO2,并稳定垃圾中重金属。考察水分添加量、CO2分压等因素并进行热重-差热实验、X射线衍射及连续浸取实验。结果表明:干燥飞灰可吸收其自身质量3%的CO2;水分添加量大于10%时,纯CO2吸收效果较好;CO2的吸收及其碳酸化过程使飞灰中C a(OH)2转化为C aCO3,同时飞灰中可交换态Pb质量的40%左右转化为碳酸盐结合态而得以稳定。

Municipal solid waste （MSW） incinerator fly ash works effectively as a calcium sorhent for sequestration of CO2 to reduce CO2 emissions as well as stabilization of heavy metals in the fly ash. The effect of the water content and CO2 pressure on the capture mechanism was evaluated using thermogravimetry analysis-differential thermal analysis （TGA-DTA）, X-ray diffraction （XRD） and sequential extraction procedure. The results show that the MSW incinerator fly ash can capture CO2by 3% of the ash mass. Water contents of 10%0 （by mass） or more added to the fly ash remarkably accelerates the CO2 capture. The COz combines with Ca（OH）2 to form CaCO3 and COz also converts 40 % （by mass） of the exchangeable Pb into the carbonated form to also stabilize Pb.