Membrane treatment

U.S. EPA, Membrane Treatment ofWood Preserving Site Groundwater by SBP Technologies, Inc., Applications Analysis Report, EPA/540/AR-92/014, Washington, D.C., 1993. 

Nakhla, G., Lugowski, A., Patel, J., and Rivest, V., Combined biological and membrane treatment of food-processing wastewater to achieve dry-ditch criteria Pilot and full-scale performance, Bioresource Technology, 97,1-14, 2006. 

Membrane treatment is a very effective technology used in a broad range of applications. It has been used for desalinization, specific ion removal, nutrients and suspended solids removal, and nowadays plays an important role in removal of trace-level organic contaminants dissolved in water. It is a very advantageous... 

A continuing major objective in the search for alternative commercial membranes is stability against active chlorine. Control of biological growth upstream of the membrane appears desirable in most practical water systems. Removal of chlorine prior to membrane treatment is expensive and potentially hazardous should the removal system fail. The polymer chosen for the... 

Postcolumn UV irradiation to destroy the structure of organic compounds leaving the chromatographic column Oxidizing organic matter contained in the sample Hybrid photocatalysis/membrane treatment of water UV digestion of the sample... 

Le-Clech, P., E.-K. Lee, and V. Chen. 2006. Hybrid photocatalysis/membrane treatment for surface waters containing low concentrations of natural organic matters. Water Res. 40 323-330. 

N. Flilal, H. Al-Zoubi, A. Mohammad, A. Abu-Arabi, A comprehensive review of nanofiltration membranes treatment, pretreatment, modelling and atomic force microscopy, Desalination 170 (2004) 281-308. 

Membrane treatment Gas Permeability x 10 (cm (STP)-cm/s-cm2-cm Hg) Measured selectivity Knudsen selectivity... 

Alumina membranes with a pore diameter of 0.2 pm have been tested successfully for removing emulsified EDC [Lahiere and Goodboy, 1993]. The soluble EDC, however, is not affected by the membrane treatment and remains at the same level before and after the operation. Pilot test results show that the water recovery is about 94%. The steady stale permeate flux from the pilot test at 30-45 C is 1290 Lfhr-m which is about 4 to 6... 

Effect of membrane treatment conditions on the permeate flux and separation factor of a 5% ethanol/water mbcture at 60 C by silicalite membranes... 

Soybean oil does not have as much of a color problem as do cottonseed and peanut oils. Reductions of yellow color were insignificant, but 50% reductions in red color values were achieved. Beta-carotene content was not influenced by the membrane treatment, although chlorophyll contents of the permeates were reduced. The best results were obtained with cottonseed oil, where color readings were reduced from 2.5 R-16 Y in the crude oil to 0.4 R-3 Y. Beta-carotene content was significantly reduced by polyvinylfloride membrane (Table 12). 

Only a few recent studies have dealt with the use of photoactive membranes prepared by immobilization of titania particles in polymeric membranes or deposition of porous titania coatings. " They were concerned with photooxidation applications like antifouhng or elimination of small organic molecules that cannot be stopped by conventional membrane treatments, but which are very harmful to the environment, like VOCs. 

In particular, membrane bioreactors (MBRs) are today robust, simple to operate, and ever more affordable. They take up little space, need modest technical support, and can remove many contaminants in one step. These advantages make it practical, for the first time, to protect public health and safely reuse water for non-potable uses. Membranes can also be a component of a multi-barrier approach to supplement potable water resources. Finally, decentralization, which overcomes some of the sustainability limits of centralized systems, becomes more feasible with membrane treatment. Because membrane processes make sanitation, reuse, and decentralization possible, water sustainability can become an achievable goal for the developed and developing worlds. 

The use of an integrated membrane process for the clarification and the concentration of citms and carrot juices was proposed as an alternative to the traditional techniques of the agro-food industry [151]. The ultrafiltration process was studied on a pilot plant unit to clarify the raw juice. A clear phase was produced in this step and it was used for concentration by successive membrane treatments. The RO process, performed on a laboratory plant unit, was used to preconcentrate the permeate from UF up to 15-20 g TSS/lOO g. A final OMD step yielded a concentration of the retentate from the RO up to 60-63 g TSS/lOO g. 

It has been demonstrated that membrane separation processes can be successfully used in the removal of radioactive substances, with some distinct advantages over conventional processes. Following the development of suitable membrane materials and their long-term verification in conventional water purification, membrane processes have been adopted by the nuclear industry as a viable alternative for the treatment of radioactive liquid wastes [1]. In most applications, membrane processes are used as one or more of the treatment steps in complex waste treatment systems, which combine both conventional and membrane treatment technologies. These combined systems have proved more efficient and effective for similar tasks than conventional methods alone. 

One of the current researches devoted to membrane treatment of radioactive waste is directed toward seeded ultrafiltration and all methods, which combined with ultrafiltration, give considerable enhancement of separation (Table 30.6). 

Rainey, R.H. et al., Separation of radioactive xenon and krypton from other gases by use of permselective membranes. Treatment of Airborne radioactive Wastes, Proceedings of a Symposium, New York, 26-30 August 1968. 

In relation to future trends of the membrane treatments described in this chapter, they are expected to be applied for medical and research wastes of low-medium activity contaminated with Cs, or other radioisotopes with similar characteristics. Furthermore, membrane treatment has been proved as an efficient and quick treatment in an incident that generates low-medium radioactive wastes. 

Another pilot study on UF-RO membrane treatment of industrial effluent (pulp and paper mill effluent) showed that UF permeate flux increased with temperature of feed water. The fluxes were 1.44 and 1.84 times higher at 30°C and 40°C, respectively compared... 

A. Cassano, J. Adzet, R. Mofinari, M. G. Buonomenna, J. Roig, and E. Drioli, Membrane treatment by nanofiltration of exhausted vegetable tanning liquors from the leather industry. Water Research 37, 2426-2434 (2003). 

Modular design of membrane treatment systems allows easier future expansion. 

Inorganic salts Carbonate Phosphate Silicate Subcarbonate Subnitrate Reacts slowly with HCl of stomach and inhibits secretion by lining the mucous membrane. Treatment for gastric and duodenal ulcers, gastritis, dyspepsia, and functional disorders of colon and peptic ulcers. In ointment used as a protective or sedative agent on inflamed skin... 

Membrane Treatment of Wood Preserving Site Groundwater by SBP Technologies, Inc. Applications Analysis Report... 

Separation of Hazardous Organics by Low Pressure Membranes Treatment of Soil-Wash Rinse-Water Leachates... 

In variant 1.2, which is the subject of patent claims by Exxon in particular [12, 15, 17, 18], the entire stream flows through the membrane stage, giving rise to considerably higher loadings of the membrane material. The membrane treatment of the mainstream of the organic phase may be advisable, if the preseparation by decantation is still convenient and only traces of the aqueous phase have to be separated. 

Ultrafiltration treatment of enzymatic hydrolysates can further reduce the immunoreactivity of whey protein in vitro [179]. Nakamura and coworkers [176,177] stated that combinations of hydrolysis and membrane treatment (microfiltration or ultrafiltration) result in a desirable hypoallergenic peptide. The antigenicity of the fractions decreased with the decreasing of the pore size of the ultrafiltration membrane. 

A summary of key characteristics of natural organics and the possible implications of these characteristics on treatment is shown in Table 2.4. The effect of some of these characteristics on membrane treatment is investigated in more detail in Chapter 3. 

The optimum coagulation conditions (i.e. pH) were found to be the same as in conventional treatment for removal, but optimal flux in membrane treatment requires further optimisation. Vickers et al (1995)... 

Jacangelo J.G., Watson M., Herndon V. (1999), Basis concepts for the use of membrane technology in dtinidng water treatment, ICOM 99, Workshop of Membrane Treatment for Drinking Water, Toronto, Canada. 

Lozier J., Jones G. (1997), Meeting the challenges of the new drinking water regulations with dual-membrane treatment, Proc. AWVC A Membrane Technolog) Conference, New Orleans, Feb. 97. 

Having interests in the application of membranes and in physico-chemical aspects of water treatment we have been fortunate to work with and support Andrea Schafer in her journey into the complex world of NOM and membrane treatment. The literature on both topics is very large and growing. This book is comprehensive in its coverage of other work. However few texts have tackled the combined topics in such detail as this. Importantly this text provides a detailed and meaningful comparison between the membrane options. 

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