兰州石化泥油薄层干化特性及干化模型建构

Drying Models and Characteristics of Thin Layer Sludge in Oily Sludge from Lanzhou Petrochemical Company

为实现炼化三泥的减量化和资源化利用,搭建薄层干化实验台;以兰州石化某炼厂炼化三泥为研究对象,实验研究干化过程的物料厚度、干化风速和干化温度三个主要因素对于干化效果的影响。在参数研究基础上,通过对实验数据进行模型拟合,得到模型参数与三个因素的关系。结果表明:当干化温度提高、干化风速增大、薄层厚度减小时,被干化的物料会在较短时间内达到干化平衡状态。干化温度和风速主要作用于干化的升速阶段和恒速阶段,薄层厚度主要作用于降速阶段。得到实验的最佳条件为干化温度120℃,干化风速2. 75 m/s,干化厚度3 mm。经过薄层干化后的样品含水率小于2%,体积明显减小;研磨后呈粉末状,基本无黏性,实现了减量化;也为资源化奠定基础。此外,利用Karathanos干化模型建立了扩散系数的对数与温度倒数的线性关系,计算出各工况下的活化能和扩散因子,为三泥的薄层干燥处置方案提供了技术指导。

In order to achieve the reduction and resource utilization of oily sludge,a thin-layer drying experiment platform was set up. Taking the refinery sludge of Lanzhou Petrochemical Company as the research object,the effects of material thickness,drying air velocity and drying temperature were studied experimentally. On the basis of parameter study,the relationship between model parameters and three factors is obtained by fitting the experimental data. The results show that when the drying temperature and drying wind speed increases,and the thickness of the thin layer is decreases,the dried material will reach the dry equilibrium state in a short time. The drying temperature and wind speed mainly act on the acceleration and constant speed stages of the drying,and the thickness of the thin layer mainly acts on the deceleration stage. The optimum conditions for the experiment were drying temperature of 120 ℃,drying wind speed of 2. 75 m/s,and drying thickness of 3 mm. After the thin layer is dried,the moisture content of the sample is less than 2%,the volume is obviously reduced,and it is powdery after grinding. It is basically non-sticky,and the reduction is realized,which also lays a foundation for resource utilization. In addition,the Karathanos drying model was used to establish the linear relationship between the logarithm of the diffusion coefficient and the reciprocal of the temperature,and the activation energy and diffusion factor under various working conditions were calculated,which provided technical guidance for the thin mud drying treatment scheme of the oily sludge.