新标准下垃圾焚烧飞灰化学稳定技术的比选和研究

研究了新的生活垃圾填埋场污染控制标准(GB168892008)实施后，飞灰要进入生活垃圾卫生填埋场时传统的重金属稳定方法可行性，并在此基础上提出了新的复合药剂稳定法.研究结果表明，已经报道的化学药剂稳定法均有必要重新检验其对重金属的稳定效果是否满足新的填埋标准的要求.绿矾与TMT-18配合使用、绿矾用量为25%（质量分数）以下、TMT-18的用量为8‰左右时完全可以使飞灰中所有重金属浸出浓度满足新的填埋标准要求，是处理二噁英含量不高于3 ng·g-1(以TEQ计)飞灰的一种经济处理技术.对二噁英含量高于3 ng·g-1 (TEQ)的飞灰，采用绿矾辅助水热处理的方法可以稳定包括Pb、Cd在内的所有重金属和降解二噁英使之符合新填埋标准对飞灰填埋的要求.

Selection of chemical stabilization technologies for treatment of fly ash from municipal solid waste incineration (MSWI) to meet the new landfill standard

Several traditional chemical stabilization methods for fly ash from municipal solid waste incineration ( MSWI) were tested to check their applicability for the new landfill standard ( GB16889-2008). Based on the results, new combined chemical treatment methods are put forward in this paper. Our experimental results show that the previously reported treatments, especially chemical stabilization methods, need to be tested to confirm that they meet the requirements in the new standard. When copperas (FeSO_4·7H_2O) is matched with a commercial heavy metal precipitator, TMT-18, with the amount of the former less than or around 25% wt and the latter about 8‰ wt of fly ash to be used as stabilizing agent, leaching of all of the heavy metals from the treated MSWI fly ash was below the limits required in the new landfill standard. This method can be recommended for treatment of fly ashes with initial dioxin contents lower than 3 ng · g~(-1) (ITEQ) . For fly ashes with higher dioxin contents, a hydrothermol treatment method with copperas as an auxiliary stabilizer is proposed to stabilize all heavy metals including Pb, Cd as well as to decompose dioxins before the fly ashes are fit for sanitary landfills.