白云石矿在燃煤脱硫中应用研究

Study on Application of Dolomite Ore in Coal Desulfurization

以白云石矿为脱硫剂,研究了不同脱硫温度、不同Ca/S值(CaO与SO_2摩尔比),以及添加CaCl_2·2H_2O脱硫助剂对燃煤脱硫性能的影响。结果表明,白云石矿具有较好的脱硫性能,在空气流量200 mL/min,Ca/S=2,随着脱硫温度升高脱硫效率逐渐增加,900℃时,白云石脱硫效率可达75.23%。随着Ca/S值增加脱硫效率快速增加,Ca/S值超过2后脱硫效率缓慢增加。白云石中添加CaCl_2·2H_2O改性剂可以明显提高白云石脱硫效率,添加3%CaCl_2·2H_2O时脱硫效率可以从75.23%提高到84.58%。采用XRD和FESEM对脱硫产物进行物相和显微形貌表征,探索了白云石脱硫过程及机理。

Dolomite was used as desulfurizer during coal combustion in this study. The effects of different desulfurization temperature, different Ca/S ratio （molar ratio of CaO to SO2） and adding CaCl2·2H2O as assistant on desulfurization performance were studied. The study found that the dolomite has good desulfurization performance. The desulfurization efficiency of dolomite is 75.23% under the condition of 900 ℃, Ca/S=2 and air flow rate is 200 mL/min. With the increase of Ca/S, the desulfurization efficiency increased rapidly while Ca/S increased from 1 to 2. When Ca/S exceeded 2, the desulfurization efficiency increases slowly. The study found that adding CaC12-2H,O in dolomite can obviously increase the desulfurization efficiency. The desulfurization efficiency can be increased from 75.23% to 84.58% when adding 3% CaCl2·2H2O in dolomite. The dolomite desulfurization process and its mechanism were explored through the study of the phase and microscopic morphology analysis of desullhrization products by XRD and FESEM.