新型泡沫碳化硅塔板的流体力学及传质性能

利用碳化硅泡沫材料的孔隙率高、表面积大、强度大、耐腐蚀和不漏液等优点,将其应用到塔板上,开发出新型整体多孔碳化硅泡沫塔板.将一定孔径的碳化硅泡沫材料制作成厚度为12,mm的块状塔板,在φ600,mm的塔内进行流体力学实验,测定了干板和湿板压降、雾沫夹带及漏液量等参数;以环己烷-正庚烷为标准物系在φ300,mm的传质塔中进行了传质实验研究,在常压、全回流条件下测定了全塔效率来表征塔板传质效率;选择按工业设计标准制成的筛板与其性能进行比较.结果表明:泡沫孔径为2,mm的塔板压降过高;泡沫孔径为4,mm的塔板漏液较多,且出现不均匀漏液;而孔径为3,mm及3~4,mm组合的两种新型塔板具有压降低、雾沫夹带少、漏液少和全塔效率高等特点,是流体力学及传质性能优良的新型泡沫塔盘.

Hydrodynamics Behavior and Mass Transfer Performance of Novel SiC Foam Trays

With its advantages of high porosity,high surface area,high mechanical strength,good resistance to corrosion and no-leakage construction,SiC foams have been applied to tray columns to develop a series of novel trays. SiC foams with the thickness of 12,mm and various sizes of pores were used for making trays in the hydrody-namic experiments. Performance parameters including pressure drop for the dry and wet trays,entrainment and the quantity of leaking liquid were measured in a 600,mm external diameter column. The mass transfer efficiency in terms of the overall column efficiency was determined by total reflux experiments using a mixture of n-heptane and cyclo-hexane at atmospheric pressure in a column of 300,mm external diameter. Sieve trays designed according to the indus-trial standards were chosen for the performance comparison with the SiC foam trays. Results show that the pressure drop of the tray with 2,mm pore diameter is too high;there is a serious leaking of liquid for the tray of 4,mm pore diameter with the phenomenon of mal-distributed weeping;compared with sieve tray,the trays with the sizes of pores being 3,mm and 3-4,mm combination performed better with low pressure drop,small entrainment,little leaking of liquid and high overall column efficiency.