(東北大學(xué) 資源與土木工程學(xué)院，沈陽 110819)
摘 要: 為深入了解高磷鐵礦煤基還原過程中氟磷灰石還原行為的影響因素和等溫動力學(xué)參數(shù)，試驗采用純礦物配比的方式研究了二氧化硅含量、氧化鐵含量、碳用量、還原時間和還原溫度對磷灰石還原度的影響，并在此基礎(chǔ)上，探明Ca10(PO4)6F2-SiO2-Fe2O3-C體系下氟磷灰石還原的等溫動力學(xué)機理函數(shù)和動力學(xué)方程。結(jié)果表明：在一定的條件下，增加二氧化硅、氧化鐵、碳用量、還原時間或還原溫度均能夠促進氟磷灰石的還原反應(yīng)。在Ca10(PO4)6F2-SiO2-Fe2O3-C體系中，二氧化硅和氧化鐵與氟磷灰石的最佳含量比分別為1.8和2.2，最佳C/O摩爾比為2.0。在最佳反應(yīng)物用量條件下，氟磷灰石深度還原的最佳動力學(xué)機理函數(shù)為A1/3：1/3(1-α)[-ln(1-α)]-2；最佳動力學(xué)方程為：k(T)=3.89033×107exp(-282.748×103/RT)，其中，指前因子為3.89033×107 min-1，活化能為282.748 kJ/mol。還原反應(yīng)的限制環(huán)節(jié)為固態(tài)擴散。
關(guān)鍵字: 氟磷灰石；Ca10(PO4)6F2-SiO2-Fe2O3-C體系；影響因素；動力學(xué)方程
（College of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China）
Abstract:To study the influencing factors and isothermal kinetic parameters of fluoropatite reduction in the process of coal-based reduction of high-phosphorus iron ore, the effects of reduction time, reduction temperature, and content of silica, iron oxide or carbon on reduction degree of fluorapatite were studied by mixing pure minerals in the experiment. On this basis, the reduction kinetic mechanism function and isothermal kinetic equation of fluoroapatite in Ca10(PO4)6F2-SiO2-Fe2O3-C system were investigated. The results show that increasing the amounts of silica, iron oxide and carbon, and decreasing time and temperature, can accelerate the reduction reactions of fluoroapatite under experiment conditions. In Ca10(PO4)6F2-SiO2-Fe2O3-C system, the optimum ratios of silica, iron oxide comparing to fluorapatite are 1.8 and 2.2, respectively, and the optimal C/O molar ratio is 2.0. Based on the optimum amount of reactants, the best mechanism function for the reduction of fluoroapatite is the A1/3: 1/3(1-α)[-ln(1-α)]-2; the best kinetic equation is K(T)=3.89033×107exp(-282.748×103/RT), where the pre-exponential factor is 3.89033×107 min-1, and the activation energy is 282.748 kJ/mol. The limiting factor of the reduction reaction is solid-state diffusion.
Key words: fluoropatite; Ca10(PO4)6F2-SiO2-Fe2O3-C system; influencing factors; kinetic equation
