过滤器原理及优化.pdf

默默克密理克密理博博 高智高智群群 18616576991 leo.gao@ Introduction to Filtration 过滤知识及基本原理过滤知识及基本原理 0.22 µm 1 2 3 4 5 3 主要内容主要内容 Important differences in the types of filters used in Bioprocesses. 生物制药中使用的不同类型过滤器及其特性 Why we use membrane filters for critical application 关键应用中为什么使用膜过滤器 How to recognize filtration problems and perform basic troubleshooting 怎样理解过滤中的问题和解决简单故障 4 什么是过滤什么是过滤？？ 5 How do Filters Work? 过滤机理过滤机理 Size Exclusion大小排除  Particles are too large to pass through the “pore” 基于大小来分离 Examples are termed entrapment, sieving, surface capture 例如拦截,筛分,表面捕获 Adsorption吸附  Particles stick to the filter by chemical / electrical attraction 颗粒由于化学/电荷作用粘附在滤器上 6 Retention Mechanisms影响过滤的因素影响过滤的因素 Mechanisms can be affected by: 截流机制可以被以下因素影响 Fluid characteristics 流体特性 Operating conditions 操作条件 Particle type 颗粒类型 Filter type 过滤膜类型 7 影响过滤的因素影响过滤的因素( (流体特性流体特性) ) Viscosity粘度 Chemical / Ionic content 化学/离子成分 Comments  Slow flow allows more contact较慢流速有 较多接触  Mixing/Contact time can be critical混合/接 触时间有较大影响 Only affect adsorptive retention 只影响吸附截留 NOT size exclusion 不影响大小排除 8 影响过滤的因素影响过滤的因素( (操作条件操作条件) ) Particle speed / velocity 颗粒速度 Applied pressure过滤压力 Comments建议建议  Slow flow is good 选择低流  Better retention at slower flow 越低的流速,越好的截留  Matrix movement is bad 结构移动是不利的  particles and fibers can be released from depth filters 颗粒和纤维能从深层过滤器析出 Velocity/Differential Pressure can have a major effect on adsorptive retention - Little to no effect on size exclusion 速度/压差对吸附截留有重要影 响,对大小排除影响相当小 9 影响过滤的因素影响过滤的因素( (颗粒类型颗粒类型) ) Deformable (soft)可变形颗粒 Non-deformable (hard) 不可变形颗粒 Comments建议建议 Under pressure soft particles can intrude into the filter structure causing more effective filter blinding 在压力下软性颗粒会进入过滤膜并导致 更多的过滤堵塞 例如:凝胶  Hard particles form open cakes 硬颗粒形成一层饼 例如:沙子 10 影响过滤的因素影响过滤的因素( (滤膜的影响滤膜的影响) ) Pore rating孔径 Structure结构 Rigid or movable刚性或可移动 Comments  Sterilizing filter - common rating (legal definition) 除菌过滤-公共孔径(法规定义)  Prefilters have nominal ratings - each manufacturer has their own standards and methods 预过滤---额定孔径,每一个制造商有自己 的定义和方法 0.22 um Durapore Surface (3,000x) 0.22 um Durapore Cross-section (600x) 11 Filter Materials – Hydrophilic 过滤材质过滤材质—亲水性亲水性 “Water Loving”亲水 Wet spontaneously (or with little effort) with water水可浸润的 Cellulosic materials (i.e. Regenerated cellulose, mixed cellulose ester, etc.) 纤维素材料(再生纤维素,混合纤维素酯 Polycarbonate with additives (i.e. PVPP),聚碳 酸酯,Modified polysulfone改良聚乙烯, Nylon尼 龙, Modified polyvinylidene fluoride (PVDF)改良聚 偏二氟乙烯 Applications应用 Filtration and sterile filtration of aqueous or aqueous / organic solutions 水或水/有机溶液 混合的过滤和除菌过滤 12 Filter Materials – Hydrophobic 过滤材质过滤材质——疏水性疏水性 “Water hating”疏水  Not spontaneously wet with water.水不浸润  Water can remain or be “tricked” to enter filter 水被截 流或”引导”进入膜  PTFE - Polytetrafluoroethylene, 聚四氟, PVDF - Polyvinylidene fluoride聚偏二氟乙烯 Polypropylene聚丙烯, Polysulfone聚砜, Polycarbonate聚碳酸酯 Applications应用  Solvent, acid, base, and chemical filtration 溶剂,酸,碱和化学品过滤  Tank/Equipment vents, process gas, fermentation inlet/exhaust filters 罐/设备呼吸器,工艺用气,发酵进气/排气过滤 Filter Structure 过滤器结构过滤器结构 14 What do Depth Filters look like? 深层过滤器深层过滤器 Fibrous (can shed fibers) 纤维(有纤维脱落) Difficult to give an accurate pore size rating 不能给出一个确切的孔径 Thick (3 - 30 mm) & often adsorptive 厚度(3-30毫米),通常有吸附 Give a percentage (i.e. 30 - 70%) particle reduction 只能给出颗粒减少的比例 Have the greatest capacity 较大的承污能力 Examples - Microfiberglass, String-wound, pad filters 例如-玻璃纤维,线绕式,压板式 15 What do Surface Filters look like?表面过滤器表面过滤器 Fibers locked together by heat or membrane coating 纤维用热粘合或膜涂布 Given a nominal rating or rated by the filter it protects 可以给出额定孔径 Thin (1 mm or less) & Slightly Adsorptive 较薄(小于1毫米),较小吸附 Give a percentage (90 - 99.9%) particle reduction 给出颗粒减少的比例(90-99.9%) Examples - Cellulose ester coated cellulose or polyester web 例如-纤维素酯涂纤维或聚酯片 16 Key Membrane Filter Characteristics 膜过滤器的特性膜过滤器的特性 Strong, Rigid NOT brittle 坚强，硬不易碎 Tortuous pathway 曲折的通道 Not all the retention on top 不是都截流在膜表面 Very high internal area 非常高的内表面积 65-75% porosity 65%-75%开孔率 Size exclusion – particleb retention does not change with flow or pressure 大小排除－颗粒截流与流速和压力无关 Sterilizing filters must have 99.99999% removal and sterile filtrate 无菌过滤器必须具有大于99.99999%截流 Integrity testable (diffusion &/or bubble point) 能做完整性测试 17 How are Membrane Filters Made? 膜过滤是怎样制造的？膜过滤是怎样制造的？ Produced by Casting 铸造膜 Nylon, Cellulose (mixed ester, regenerated), PVDF, Polysulfone 尼龙,纤维素(混合酯,改良),聚偏二氟 乙烯,聚砜 Produced by Stretching拉伸膜 PTFE 聚四氟乙烯 MIXING THICKNESS CONTROL MEMBRANE CASTING HYDROPHILISATION DRYING ENVIRONMENTALY CONTROLLED CHAMBER 3:11 18 What do Cast Filters look like? 铸造方式制造的膜过滤器铸造方式制造的膜过滤器 Mainly made by casting membrane 主要由铸造方式制造 Can be either hydrophilic or hydrophobic 可以是亲水和疏水 Rated on the size of the smallest particle it retains 孔径是对最小的颗粒的截留 Very thin (100 - 260 um) 非常薄（100-260微米） Adsorption depends on materials 吸附与材料相关 Examples例如 Cellulose ester纤维。