脱硫石膏粒径分布与脱水性能实验研究

Experimental study on particle size distribution and dewatering performance of FGD gypsum

脱硫石膏粒径分布是影响脱硫石膏浆液脱水性能的重要因素之一,以干法、湿法筛分和研磨破碎获得不同粒径分布的脱硫石膏,在相同的过滤条件下,对不同粒径分布脱硫石膏浆液脱水性能进行了研究,实验结果表明,当脱硫石膏粒径d50大于50μm且(d90-d10)小于100μm,真空过滤最大真空度不低于0.098 MPa,过滤时间不少于2.5 min,滤饼厚度不超过20 mm时,石膏滤饼含水率可以降低到12%以下(最低可达10%);d50在17μm为脱硫石膏在相同的过滤条件下能够实现真空脱水干燥的转折点;d50和(d90-d10)共同影响石膏脱水性能,d50小于20μm时,仅表现为d50的影响。

The particle size distribution is an important factor of affecting gypsum slurry dewatering perform- ance. Through using the dry, wet screening or grinding-broken method, different particle size distribution FGD gypsum could be gotten. Its dewatering performance under the same filter condition was studied. Experimental results show that when dso is more than 50 μm and （d90 -d10 ） is less than 100 μm of FGD gypsum, the largest vacuum degree is equal or higher than 0. 098 MPa, the filter time is equal or more than 2.5 min and the thick- ness of filter cake is equal or less than 2 cm, the water ratio of gypsum will be less than 12% （and even to 10% ）. When dso is 17 μm, the FGD gypsum can reach the the turning point of gypsum slurry vacuum dewate- ring and drying under the same filter condition; both d50 and （d90 -d10 ） affect the gypsum dewatering perform- ance, but when d50 is less than 20 μm, only d50 plays a part in gypsum dewatering performance.