Standard Operating Procedure - Ultrafiltration - Department of ...

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Cleaning TheoryTHE CHEMISTRY OF MEMBRANE CLEANINGThe use of membranes in many fields (food industry, water treatment, pharmaceuticals,biotechnology, and industrial waste treatment) is on the increase. As more and more applicationsare found, more and more membrane systems are devised, thus, the difficulties in cleaning theseplants increase and become more complex. We know that regulatory agencies such as FDA,USDA etc. are getting more involved by the day in inspection of new technologies andprocesses, and membrane filtration is one of them.What is so different about membrane cleaning as compared to tank cleaning or evaporator ortankers? In most processing or engineering fields, the material we encounter is metal, stainlesssteel or maybe sophisticated, complex blends of alloys and the like. Membranes for the mostpart are made of different material and because of the manufacturing process, the particularcharacteristics, membranes are simply much more expensive per unit area than normal material.When damaged, they cannot be repaired, they have to be replaced at great cost. They are muchmore fragile and more sensitive to all sorts of influences.Ecolab, having been involved in the cleaning of membranes from the beginning of theirintroduction into the food processing field, thought that in view of the many inquiries comingfrom the membrane manufacturers and users alike, a session on theoretical and practical aspectsof membrane cleaning would allow us to clear up some important points. While membranecleaning is different, it is not necessarily difficult or scary.There are many membrane filtration systems in use today. It is not our purpose to list them all,to explain their differences, advantages or disadvantages. The literature available by most of themanufacturers will provide some idea of new developments. We must define a few basic termsas a starting point of our discussion.Filtration techniques can be classified according to the molecular or particle size that isseparated.Microfiltration, also called cross flow filtration is in the range of 1/100 to 1/10,000 of amillimeter. Small particles, living cells, i.e. bacteria and large colloids fall into this category.Ultrafiltration goes beyond the particle size. Here we filter molecules, which are dissolved insolution (it may be a perfectly clear solution with no visible cloudiness). Those molecules arecalled MACROMOLECULES; they are usually long chains composed of smaller links (protein,starch, and oily substances). Smaller molecules such as sugar, salts, etc., go through a UFmembrane. UF membranes are pore-membranes with transition paths of varying size, therebyeffectively selecting different molecular sizes.56
Reverse Osmosis is the technique (also called hyperfiltration) where practically nothing but thesolvent, i.e. water, goes through the membrane. All dissolved substances remain on theconcentrate side.A somewhat different process designed to remove ions, (charged molecules or atoms from asolution) is called Electrodialysis. There the combined effects of electrical field and membraneselectivity are used in the separation.Membrane separations, independent of the size of the entities to be separated, can also beclassified according to the design of the modules holding the membranes. Again, please alwaysrefer to the manufacturer’s literature for details. There are many different types, each withadvantages and disadvantages. Plate and spacer modules assembled like a plate heat exchanger,spiral wound modules, hollow fiber modules and tubular modules reminiscent of tubular heatexchangers, are the most common ones.Still another way of categorizing membranes is by the composition material. It all started withcellulose acetate and derivatives, and then synthetic polymeric membranes appeared, made ofpolysulfone, polyamide, polycarbonate, polyacrylate and many more. Then there are the nonpolymeric,inorganic membranes made of carbon with an active layer of zirconium oxide andlately the aluminum oxide membranes.One of the most important items to consider when talking about cleaning is the particularapplication of the membranes. The fouling (soiling of the membrane during process) plays amajor role in the success of the cleaning procedure. Membranes are used to filter:• cells in biotechnology• valuable drugs in pharmaceutical industry• alcohol in making alcohol free beer• orange and other fruit juices• blood• kraft fluids• oil emulsions• waste water• liquid egg preparations• salt water and many othersThe term sanitation is somewhat unclear and vague. Sometimes it is used to mean cleaning andsanitizing together, as a sort of general expression. Sometimes it means the specific step of usinga sanitizer to kill bacteria and other microorganisms. We will concentrate on cleaning, theremoval of oil in this section. Sanitizing will be discussed separately later.57
Page 1 and 2: GEA Filtration Model L Pilot PlantS
Page 3 and 4: Purpose and ScopeThis SOP covers th
Page 5 and 6: Personnel ProtectionSafety glasses
Page 7 and 8: High Pressure ClampsATTENTIONSAFETY
Page 9 and 10: Waste and Hazardous MaterialsStorag
Page 11 and 12: The typical work flow for operating
Page 14: Design BasisThe GEA Filtration Mode
Page 18 and 19: 1 Lab-Module M 20The Lab-Module has
Page 20 and 21: Defoamer IntoleranceUse of anti-foa
Page 22 and 23: CONDUCTIVITYUsed as an approximate
Page 24: PROCESSGenerally, the process of se
Page 27: The amount of salt, which passes th
Page 30 and 31: Pre Start-Up Procedure1. Use the wh
Page 32 and 33: 10. (For use with the Scepter housi
Page 34 and 35: Note: there may be residual fluid i
Page 36 and 37: 12. Install correct pressure gauges
Page 38 and 39: ShutdownOnce the desired amount of
Page 40 and 41: FlushThis step is used after Produc
Page 42 and 43: Membrane PreservationIf the system
Page 47 and 48: Lab Stack Membrane Assembly -Shiny
Page 49: The GEA Pilot plant utilized differ
Page 59 and 60: the endurance of the membrane, flux
Page 61 and 62: are more difficult to degrease, to
Page 63 and 64: Metal ions, such as high amounts of
Page 65 and 66: Among other things the blend is eas
Page 67: Oxidizer IntoleranceIf you have a r

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