Zinc recovery from MSWI fly ash using acidic leaching and chemical precipitation was studied at pilot scale. The leached fly ash was re-incinerated in order to destroy toxic dioxins. 75–150 kg/h of fly ash from a Swedish Waste-to-Energy plant was mixed with scrubber liquids from the same flue gas treatment system in a continuously stirred vessel. The resulting slurry was dewatered in a vacuum belt filter. Hydroxide precipitation of the produced leachate, at a pH of around 9, followed by filtration of the formed crystals in a membrane filter press produced a filter cake with up to 80 wt% Zn(OH)₂ in dry solids, calculated from Zn(tot). Up to 70% of the zinc content in the fly ash could be recovered. Two 4-hour full scale ash re-incineration tests were performed: leached fly ash was mixed with the waste at a ratio corresponding to a situation where all the fly ash was continuously re-incinerated. The tests showed only an 8% mass increase of produced fly ash, which means that most of it ended up in the bottom ash, although some elements could potentially accumulate in the system if all the fly ash was to be continuously re-incinerated. No negative effects were observed on the bottom ash quality, which suggests that a large portion of the toxic fly ash could be transformed into the bottom ash fraction.

以中试规模研究了使用酸性浸出和化学沉淀法从MSWI粉煤灰中回收锌的方法。重新焚烧沥出的粉煤灰以破坏有毒的二恶英。在连续搅拌的容器中，将瑞典废物转能源工厂的75–150 kg / h的粉煤灰与同一烟气处理系统中的洗涤器液体混合。将所得浆液在真空带式过滤器中脱水。在大约9的pH值下，生成的渗滤液的氢氧化物沉淀，然后在膜压滤机中过滤所形成的晶体，生成的滤饼含Zn（OH）₂最高为80％由Zn（tot）计算得出的干燥固体中的含量。可以回收粉煤灰中高达70％的锌含量。进行了两个4小时的全尺寸灰烬再焚化试验：将沥滤过的粉煤灰与废物混合，其比例与所有粉煤灰不断被焚化的情况相对应。测试表明，生产的粉煤灰的质量仅增加了8％，这意味着大部分粉煤灰最终残留在了底灰中，尽管如果要对所有粉煤灰进行连续焚烧，某些元素可能会在系统中积累。没有观察到对底灰质量的负面影响，这表明大部分有毒粉煤灰可以转化为底灰部分。