Millions of tons of bottom ash (BA) is generated from incineration of industrial and municipal solid waste each year within EU. The magnitude of leaching of metals like Cu and Zn is critical for hazard and risk assessment of these ashes. Although speciation of metals is a key factor to understand and predict metal leaching, speciation of Cu and Zn in BA is not well known. In this study six metal separated and carbonized BA were investigated by a combination of X-ray absorption spectroscopy, X-ray diffraction, leaching/extraction tests, and geochemical modelling. Five of the BA were from grate boilers and one from a fluidized bed incinerator. The aims were to identify similarities in Cu and Zn speciation and to identify main species. The combination of several techniques was necessary to draw conclusions about speciation and displayed coherent results. A similar speciation of Cu and Zn was indicated in the five studied grate boiler ashes although the proportions between species may vary. Copper(II) oxide and Cu metal were the main Cu species in all BA. Zinc(II) oxide and willemite (Zn₂SiO₄) were identified in grate boiler ashes. The fluidized bed ash contained Zn-Si-minerals and possibly franklinite or gahnite, while the Zn(II) oxide content was low, if any. The results have implications for classification and risk assessment of MIBA.

欧盟内部每年焚化工业和城市固体废物产生数百万吨底灰（BA）。铜和锌等金属的浸出量对于这些灰烬的危害和风险评估至关重要。尽管金属的形成是了解和预测金属浸出的关键因素，但BA中Cu和Zn的形成尚不为人所知。在这项研究中，通过X射线吸收光谱，X射线衍射，浸出/萃取测试和地球化学模型的组合研究了六种金属分离并碳化的BA。BA中有五台来自炉排锅炉，另一台来自流化床焚化炉。目的是鉴定铜和锌形态的相似性并鉴定主要物种。必须结合多种技术才能得出有关物种形成的结论并显示出连贯的结果。尽管研究对象之间的比例可能有所不同，但在所研究的五种炉排锅炉灰中都表明了类似的铜和锌形态。在所有BA中，氧化铜（II）和铜金属是主要的Cu种类。氧化锌和硅锌矿（Zn在炉boiler锅炉灰中鉴定出₂ SiO ₄）。流化床灰包含Zn-Si矿物，可能还包含富兰克石或钠长石，而Zn（II）氧化物的含量低（如果有）。结果对MIBA的分类和风险评估具有启示意义。