纳米涤纶滤料需要的时间远大于涤纶滤料, 对于各个周期的时间, 纳米涤纶滤料30个周期呈稳定趋势, 而涤纶滤料30个周期呈现明显下降趋势.

图10 稳定过滤各周期需要的时间Fig.10 Cycling time required for stabilization stage

经过老化阶段脉冲喷吹, 纳米涤纶滤料残余阻力与完成30个过滤周期需要的时间基本恒定, 降低了喷吹清灰的能耗和对滤料的机械损伤, 延长了使用寿命, 与涤纶滤料相比, 表现出优异的过滤性能.
D过程纳米膜滤料过滤效率为100%, 普通涤纶滤料过滤效率为99.81%.纳米涤纶滤料效率明显高于涤纶滤料.
3 结论
1) 通过静电纺丝的方法, 将涤纶纳米纤维膜纺制于涤纶滤料上, 在涤纶滤料与纳米纤维膜之间加入无纺布胶, 经过热压处理, 成功制备了“三明治”结构的纳米涤纶滤料.
2) 洁净过滤阶段, 纳米膜虽然增加了滤料的初始阻力, 但由于纳米膜致密且带有静电, 对颗粒物具有吸附作用, 容易形成粉尘层, 使得前15个周期阻力增长较快, 且纳米涤纶滤料完成各个周期需要的时间少于涤纶滤料; 后15个周期纳米涤纶滤料过滤性能趋于稳定, 阻力增长逐渐平稳, 且完成各个周期需要的时间大于涤纶滤料.
3) 老化阶段纳米涤纶滤料的老化程度小于涤纶滤料, 此阶段纳米涤纶滤料和普通涤纶滤料阻力分别增长了81.9 Pa和112.3 Pa, 增长率分别为66.4%和172.0%.
4) 稳定过滤阶段, 涤纶滤料的阻力高于纳米涤纶滤料.纳米涤纶滤料的残余阻力以及完成30个周期需要的时间基本趋于稳定, 与涤纶滤料相比, 阻力增长缓慢, 残余阻力稳定, 降低了喷吹清灰的能耗以及对滤料的机械损伤, 具有良好的过滤性能.
5) 无论是洁净过滤阶段还是稳定过滤阶段, 纳米涤纶滤料的粉尘剥离率均高于涤纶滤料, 过滤性能良好.
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