The transition from limestone to lime-based flue gas desulphurisation system (FGD) was tested in a power station fired with high sulphur (S)-petroleum coke to better control the emissions of key pollutants. To this end, as a request of the power station owner to IDÆA-CSIC, we surveyed the power station fired with 70% S-petroleum coke and equipped with a slaked lime-based FGD, and compared the results with data from our previous works conducted at the same power station but operated with lower co-firing rates and a limestone FGD, the purpose being to improve the understanding on the impact that different FGD technologies may have on the fate, speciation and, ultimately, the emissions of key pollutants from the power station. Our observations suggest that the reaction pathways and speciation of key trace pollutants in the gypsum slurry including Cl, Mo, Hg and Se remained largely unchanged with the transition from limestone to lime-based FGD. By contrast, As, Cr, B, U and V speciation in the gypsum slurry was sensitive not only to the FGD sorbent, likely in response to differences in the pH, but also to the absence of ligands such as F⁻.The highly alkaline lime slurry neutralised the H⁺ released by the formation of metal-complexes. This favoured the stability of trace elements in their oxy-anionic forms or forming hydroxyl complexes, as opposed to the acidic conditions in limestone-FGD gypsum from previous works. Enrichment in Mo, V and Ni in the fly ash was primarily associated with the combustion of a petroleum coke. Other elements such as Pb, As, Zn, Cu and Se were also enriched in the fly ash relative to the boiler slag.

从石灰石向石灰基烟气脱硫系统（FGD）的过渡过程在以高硫（S）-石油焦炭燃烧的发电厂中进行了测试，以更好地控制关键污染物的排放。为此，根据电站所有者对IDÆA-CSIC的要求，我们对使用70％的S-石油焦和装有熟石灰基烟气脱硫装置的电站进行了调查，并将结果与​​以前工作中的数据进行了比较在同一发电厂进行，但以较低的联合点火速率和石灰石烟气脱硫装置运行，目的是增进对不同烟气脱硫技术可能对命运，形态以及最终关键污染物排放产生的影响的了解发电站。我们的观察表明，石膏浆液中主要的痕量污染物（包括Cl，从石灰石向石灰基烟气脱硫过渡，钼，汞和硒基本保持不变。相比之下，石膏浆料中的As，Cr，B，U和V形态不仅对FGD吸附剂敏感（可能响应于pH值的差异），而且对不存在配体（例如F）敏感⁻。高碱性石灰浆中和了由于形成金属络合物而释放的H ⁺。与先前工作中石灰石-FGD石膏中的酸性条件相反，这有利于痕量元素以其氧-阴离子形式或形成羟基络合物的稳定性。飞灰中Mo，V和Ni的富集主要与石油焦炭的燃烧有关。相对于锅炉炉渣，粉煤灰中还富含其他元素，例如Pb，As，Zn，Cu和Se。