MF spiral
The microfiltration spiral membranes from Alfa Laval are based on a unique construction of polypropylene support material in a sanitary full-fit design that provides optimum cleaning conditions. The spiral membranes are available with different microfiltration membrane types and in different combinations of length, diameter and feed spacer size
Alfa Laval microfiltration (MF) spiral membranes are extremely cost-effective to operate, largely as the result of the low energy consumption involved. They also have the advantage of eliminating the frequent replacement and disposal of the cartridges and other consumables used in traditional dead-end filtration.
Alfa Laval microfiltration spiral membranes are extremely durable, with service lives that can extend over more than five years.
Microfiltration is used on feed streams where the aim is to remove small-diameter dispersed solids such as bacteria, fat and oil globules without affecting the balance of the components dissolved within the stream.
Alfa Laval offers two series of microfiltration spiral membranes with different pore sizes and flux properties. The membrane materials are either polysulphone polymer or fluoro polymer based on polypropylene support material.
MFG series
The MFG microfiltration spiral membrane is made of polysulphone polymer. The spiral membrane is avaiable in the types MFG1 and MFG2 with pore sizes of 0.1 µm and 0.2 µm respectively.
MFP series
The MFP microfiltration spiral membrane is made of fluoro polymer. This spiral membrane is available in type MFP2 having a pore size of 0.2 µm and MFP5 and MFP8 with pore sizes of 0.5 µm and 0.8 µm respectively.
Benefits
- cost-effective operation due to low energy consumption
- long life time compared to traditional dead-end filtration
- cover a broad spectrum of flux properties and pore sizes
- available in different combinations of length, diameter and spacer size
- sanitary design with all materials in compliance with EU Regulation (EC) 1935/2004, EU Regulation 10/2011 and FDA regulations (CFR) Title 21
- same membrane types available as both flat sheet membranes and spiral membranes
- suitable for extensive range of processes
- manufactured by Alfa Laval's own membrane centre
Fonctionnement
La technologie de base de la filtration membranaire consiste à utiliser une membrane semi-perméable pour séparer un liquide en deux flux distincts.
Le pompage de ce liquide à la surface de la membrane crée une pression transmembranaire positive qui permet le passage de tout composant plus petit que la porosité de la membrane, formant ainsi le perméat.
Tous les composants plus grands que la taille des pores ne peuvent tout simplement pas passer, et restent derrière dans ce que l'on appelle le rétentat. La surface de la membrane est maintenue exempte de blocages par la force du débit du liquide qui s'écoule parallèlement à la surface de la membrane.
Une membrane à spirale se compose d'un certain nombre d'enveloppes de membrane avec 2 feuilles de membrane séparées par une maille d'espacement pour perméat, chacune collée à un tube collecteur central de perméat.
Entre chaque paire d'enveloppes se trouve un espaceur qui crée le canal d'alimentation, permettant à l'alimentation de s'écouler sur toute la longueur de la membrane à spirale, tandis que le perméat passant à travers la membrane, dans son enveloppe, s'écoule à spirale vers le tube collecteur de perméat.
Rouge = Alimentation/rétentat.
Jaune = Perméat.