Institute of Environmental Assessment and Water Research (IDÆA-CSIC), Spanish National Research Council, C/Jordi Girona 18-26, 08034 Barcelona, Spain.
Institute of Environmental Assessment and Water Research (IDÆA-CSIC), Spanish National Research Council, C/Jordi Girona 18-26, 08034 Barcelona, Spain.
Ecotoxicol Environ Saf. 2021 Jan 15;208:111488. doi: 10.1016/j.ecoenv.2020.111488. Epub 2020 Oct 26.
Reducing the potential leaching of Mo and Ni from the fly ash (FA) of petroleum coke is an increasingly important issue as Asia and Europe's demand is expected to drastically intensify as continuing urbanisation and technological innovation demands ever more electricity. In the present study, we investigated coal combustion products (CCP) from a large coal-fired power station fed with a 56:44 coal/petroleum coke blend. Results revealed that leachable concentrations of Mo and Ni from FA were in the upper non-hazardous limit and in the inert limit, respectively (2003/33/EC). Whilst common prevention measures for Mo and Ni based on the adsorption capacity of boiler slag (BS), a mixture of BS: goethite, and jarosite, were considered insufficient to reduce the potential leaching of Mo into FA leachates, a novel chemical stabilisation method based on an aggregate product of portlandite and FA immobilised both Mo and Ni such that the resulting concentrations were below the limits established in the abovementioned 2003 EC Decision. Precipitation may be responsible for the fixation of Mo and Ni in the FA: portlandite aggregates as Ca(MoO) and NiMoO, respectively. The findings of this novel study support the use of this aggregate to reduce FA pollutants, which will be of particular interest to nations that remain largely coal/petroleum coke-dependant.
随着亚洲和欧洲城市化进程的推进以及技术创新对电力的需求不断增加，对石油焦粉煤灰（FA）中钼和镍潜在浸出的控制变得日益重要。本研究调查了大型燃煤电厂燃烧的混有 56:44 比例的煤和石油焦的煤燃烧产物（CCP）。结果表明，FA 中钼和镍的可浸出浓度分别在上限非危险限值和惰性限值内（2003/33/EC）。虽然基于锅炉炉渣（BS）吸附能力的常见预防钼和镍的措施，BS：针铁矿和铁矾的混合物，被认为不足以减少 Mo 向 FA 浸出液中的潜在浸出，但一种基于 FA 固定化的氢氧化钙和 FA 的聚合产物的新型化学稳定化方法，同时固定了 Mo 和 Ni，使得所得浓度低于上述 2003 年欧盟指令规定的限值。沉淀可能是 Mo 和 Ni 在 FA 中的固定化的原因：分别为 Ca（MoO）和 NiMoO。这项新研究的结果支持使用这种聚合产物来减少 FA 污染物，这对于那些仍然主要依赖煤/石油焦的国家将具有特别的意义。
