School of Metallurgy, Northeastern University, Shenyang, 110004, China; Liaoning Key Laboratory of Metallurgical Resources Recycling Science, Shenyang 110004, China.
School of Metallurgy, Northeastern University, Shenyang, 110004, China; Liaoning Key Laboratory of Metallurgical Resources Recycling Science, Shenyang 110004, China.
J Hazard Mater. 2018 Jan 15;342:436-445. doi: 10.1016/j.jhazmat.2017.08.060. Epub 2017 Aug 26.
A novel resource utilization of the calcium-based semi-dry flue gas desulfurization ash is investigated. In the present study, the semi-dry desulfurization ash is used as a reductant for chromium and vanadium removal by chemical reduction precipitation, the byproduct gypsum and chromium-contained sludge are obtained. Besides, the effects of main operational parameters (reaction pH, desulfurization ash dosage and reaction time) on the heavy metal removal are investigated, and the main reaction mechanism for this treatment technology is also proposed. Under the optimal conditions, the residual concentrations of Cr(VI), total Cr and V are 0.163mg/L, 0.395mg/L and 0.155mg/L, respectively. Additionally, byproduct gypsum and chromium-contained sludge are characterized using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscope-energy dispersive spectrometer (SEM-EDS) and thermogravimetry differential scanning calorimetry (TG-DSC), respectively. Finally, the resource utilization methods of the byproduct gypsum and chromium-contained sludge from this technology are also submitted. The byproduct gypsum can be utilized to produce hemihydrate calcium sulfate whisker, and the roasted heavy metal precipitation can be used as a primary chromium raw material (CrO content is about 83%).
研究了一种钙基半干法脱硫灰的新型资源利用方法。本研究采用半干法脱硫灰作为化学还原沉淀法去除铬和钒的还原剂，得到副产石膏和含铬污泥。此外，还考察了主要操作参数（反应 pH 值、脱硫灰用量和反应时间）对重金属去除的影响，并提出了该处理技术的主要反应机制。在最佳条件下，Cr(VI)、总 Cr 和 V 的残留浓度分别为 0.163mg/L、0.395mg/L 和 0.155mg/L。此外，还分别采用 X 射线衍射（XRD）、傅里叶变换红外光谱（FT-IR）、扫描电子显微镜-能谱仪（SEM-EDS）和热重差示扫描量热法（TG-DSC）对副产石膏和含铬污泥进行了表征。最后，还提交了该技术副产石膏和含铬污泥的资源化利用方法。副产石膏可用于生产半水硫酸钙晶须，而煅烧后的重金属沉淀可作为初级铬原料（CrO 含量约为 83%）。
