(福州大學(xué) 環(huán)境與資源學(xué)院，福州 350116)
摘 要: 為揭示硫化礦石在經(jīng)歷機(jī)械力活化后的氧化自燃特性，運(yùn)用熱分析技術(shù)表征礦樣在不同功率(100~450 r/min)、不同料球比(1:3~1:12)條件下活化后的熱分解動力學(xué)參數(shù)；采用X射線衍射技術(shù)對活化礦樣進(jìn)行線形分析，比較礦樣活化前后的晶格畸變率和晶塊尺寸。結(jié)果表明：硫化礦石在530~640 ℃溫度區(qū)間的氧化熱解過程符合一維擴(kuò)散反應(yīng)動力學(xué)機(jī)制；其表觀活化能隨著球磨功率、料球比的增加而降低，呈現(xiàn)出較好的一致性；礦樣在未活化、200 r/min、350 r/min活化條件下的表觀活化能依次為258.93、181.34、150.97 kJ/mol，對應(yīng)的指前因子分別為2.35×1018、1.45×1013和1.60×1011；礦樣在料球比為1:3、1:8活化條件下的表觀活化能依次為240.57、150.97 kJ/mol，指前因子分別為1.58×1017、1.60×1011；硫化礦石的表觀活化能的降低與活化礦樣晶格畸變率的增大及晶塊尺寸減小存在一定的相關(guān)性，進(jìn)而容易引發(fā)自燃。
關(guān)鍵字: 硫化礦石；機(jī)械活化；自燃；熱分析動力學(xué)
（College of Environment and Resources, Fuzhou University, Fuzhou 350116, China）
Abstract:In order to uncover the intrinsic influence of mechanical activation on property of oxidation and spontaneous combustion of sulfide ores, the thermal analysis technique was used to characterize the kinetic parameters of samples under different mechanical powers (100-450 r/min) and different material-ball ratios (1:3-1:12) after mechanical activation. Meanwhile, the X-ray diffraction analysis was used to obtain the lattice distortion rate and block size after mechanical activation. The results show that the kinetics reaction process of the sample complies with the diffusion one way transport mechanism under the temperature between 530 to 640 ℃. By the increase of mechanical power and material-ball ratio, the apparent activation energy of samples reduces with good consistency. The corresponding activation energy values calculated under non-activated, 200 r/min, 350 r/min are 258.93, 181.34 and 150.97 kJ/mol. and the pre exponential factors are 2.35×1018, 1.45×1013 and 1.60×1011, respectively. Meanwhile, the corresponding activation energy values calculated under 1:3, 1:8 are 240.57, 150.97 kJ/mol, respectively, and the pre-exponential factors are 1.58×1017, 1.60×1011, respectively. The reduction of apparent activation energy of mechanically activated sulfide ores is related to the increasement of lattice distortion rate and reduction of the block size, so, it can lead to spontaneous combustion under proper environmental conditions.
Key words: sulfide ore; mechanical activation; spontaneous combustion; thermal analysis kinetics
