针对中国石化催化剂长岭分公司拟薄水铝石工业装置改造过程中使用带式过滤机替代板框-浆化罐过滤洗涤后闪蒸干燥得到的产品孔体积明显低于相应的板框-浆化罐过滤洗涤产品孔体积的情况,在实验室模拟工业拟薄水铝石制备过程,研究老化及干燥条件对拟薄水铝石性质的影响,采用XRD、低温N2吸附、DTA、IR、TEM等方法对所得拟薄水铝石样品进行分析表征.结果表明,老化和干燥方式都对产品孔结构有重要影响.在快速洗涤、老化时间不足、物料结晶度低的情况下,采用烘箱慢速干燥可以得到具有较高结晶度的大孔拟薄水铝石,而采用快速干燥方式如喷雾干燥等得到的产品结晶度低、孔体积小.采取延长老化时间提高干燥前物料的结晶度后再喷雾干燥的方式,可获得大孔拟薄水铝石产品.根据研究结果,在工业装置上采用将带式过滤机洗涤过滤后的滤饼重新加水浆化、继续延长老化时间的措施,解决了工业装置改造过程中大孔拟薄水铝石的生产问题.%In the capacity expansion of pseudo-boehmite production unit, a belt filter is introduced to substitute the conventional plate-frame filter plus tank wash. It is found that the pore volume of product from this new production line is much lower than that from the conventional one. The effect of aging and drying conditions on the properties of pseudo-boehmite samples is studied in laboratory simulating the industrial production process and the obtained samples are characterized by XRD, N2 adsorption, DTA, FT IR and TEM techniques. Test results show that both aging and drying conditions have great impact on the pore structure of samples obtained. In the case of fast washing, due to lack of aging time, the crystallinity of material is low, if slow-drying (in oven) is followed, large pore volume pseudo-boehmite product with high crystallinity can be obtained)on the contrary, if fast drying (spray drying) is adopted, only poor quality product is obtained. However, prolonging aging time to increase the crystallinity of slurry prior to fast drying is also helpful for obtaining pseudo-boehmite product with large pore volume. Based on the above research results, measure of slurrying the filter cake from belt filter to prolong material aging time is proposed and put into practice on the industrial unit, since then large pore pseudo-boehmite is produced from the belt filter production line successfully.
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