基于温度效应的半水磷石膏水化反应热动力学模型  

Thermodynamic model of the hydration reaction of hemihydrate phosphogypsum based on the temperature effect

作　　者：王贻明[1] 王志凯 吴爱祥[1] 彭青松 李剑秋 WANG Yi-ming;WANG Zhi-kai;WU Ai-xiang;PENG Qing-song;LI Jian-qiu(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]贵州大学化学与化工学院,贵阳550025

出　　处：《工程科学学报》2022年第11期1811-1820,共10页Chinese Journal of Engineering

基　　金：国家自然科学基金重点资助项目(51834001)。

摘　　要：为扩大半水磷石膏(HPG)作为充填胶凝材料的工业应用半径,实现HPG资源化利用技术新突破.本文寻求一种在堆存过程中HPG水化反应放热量变化的模型,以了解其胶凝性能的变化情况.通过对初始温度为35、40、60和80℃的HPG堆体进行自由水质量分数和温度监测,发现HPG自由水质量分数变化规律符合一级反应动力学模型,之后基于热力学和化学反应动力学基本理论,提出了一种关于堆存温度与时间关系的HPG水化反应热动力学模型.最后,采用COMSOL Multiphysics数值模拟软件,将HPG水化反应热动力学方程嵌入传热和ODE模块,对HPG堆体温度进行数值模拟,模拟堆体温度变化曲线与试验结果较为吻合,验证了所提出模型的可靠性.Hemihydrate phosphogypsum(HPG),as a cementing material for mine filling,will spontaneously transform into phosphogypsum(PG) in the stockpiling state.The gelling activity decreases,and meeting the requirements of mechanical properties required for long-distance mine filling becomes difficult.The key measure in expanding the industrial application radius of HPG as a filling cementitious material is the prevention of the spontaneous conversion of HPG to PG.In-depth research on the conversion process of HPG in the storage state is required to achieve a breakthrough in the HPG resource utilization technology.In the storage process,the HPG chemical reaction will release the heat of hydration,causing the temperature and chemical fields in the system to interact with each other and promote the conversion of HPG to PG.Therefore,the HPG hydration heat release process is accurately calculated,analyzed,and simulated.This is a prerequisite to effectively inhibit the conversion of HPG.This article seeks a model of the heat release of the HPG hydration reaction during the storage process to understand the change of its gelation performance and guide on-site industrial applications.The monitoring of the free water mass fraction and the temperature of HPG stacks with initial temperatures of 35 °C,40 °C,60 °C,and 80 °C reveals that the HPG free water mass fraction change law conforms to the first-order reaction kinetic model.Based on thermodynamics and chemical reaction kinetics,a thermal kinetic model of the HPG hydration reaction on the relationship between the storage temperature and time is proposed.Using the COMSOL Multiphysics numerical simulation software,the HPG hydration reaction thermokinetic equation was then embedded in the heat transfer and ODE modules,and the HPG reactor temperature was numerically simulated.The simulated reactor temperature curve was more consistent with experimental results,and the reliability of the proposed model was verified.This model can provide guidance for the later design of the delayin

关 键 词：半水磷石膏 初始堆存温度 自由水质量分数 一级反应动力学 热动力学 数值模拟 

分 类 号：TD853[矿业工程—金属矿开采]