Waste ultrafiltration treatment

Figure Ten (10) illustrates the application of ultrafiltration to oily waste effluent treatment.

Ion exchange, reverse osmosis, ultrafiltration, and air stripping can also be used for separating waste components, especially for waste-water treatment. 

Bamier, R., Caminade, S., Foudenot, F., Maurel, M., and Courtois, F., Ultrafiltration treatment of manual laundry washes from a nuclear research centre. In Conference on Waste Management, Kyoto, Japan, 1989. 

Chaufer, B. and Deratini, A., Removal of metal ions by complexation ultrafiltration using water soluble macromolecules Perspective of application to waste water treatment, Nucl. Chem. Waste Manag. 8, 175, 1988. 

Submerged membrane bioreactors are revolutionizing waste water treatment [108]. These units dramatically increase the capacity of waste water treatment ponds while simultaneously producing a higher quality water by using an ultrafiltration membrane to remove treated water from the mixed liquor suspended solids (MLSS) produced by biological treatment. Such process intensification is one of the hallmarks of applications where membrane processes have achieved commercial success (in addition to energy reduction and purification of labile compounds). 

Figure 19.13 Waste water treatment plant in Singapore (currently ultrafiltration and ultraviolet radiation, but microbial fuel cells are under investigation at the National University of Singapore)... 

Ultrafiltration P rfport 0.01-0.1 pm Ap (<10bar) 1/1 Drinking water purification waste water treatment... 

Ultrafiltration Liquid solution containing Pressure gradient (pumping power) Two liquid phases Different permeabilities Waste water treatment protein 18, 25, 26, 51, 52... 

E. Yuliwati, A.F. Ismail, T. Matsuura, M.A. Kassim, and M.S. Abdullah. (2011). Effect of modified PVDF hollow fiber submerged ultrafiltration membrane for refinery waste-water treatment, Desalination 283 214-220. 

The chemistry of waste treatment processes and the development of new processes are fertile areas of research work. The speciation of plutonium in basic and laundry wastes is needed. For example, if soluble plutonium complexes in basic wastes can be destroyed, perhaps ultrafiltration could replace the flocculent-carrier precipitation process. The chemistry of plutonium(VII) and of ferrites—a candidate waste treatment process—needs to be explored.(23)... 

Installation of an ultrafiltration system that recovers 30 kg/d (65 lb/d) of waste oil and purifies 1135 kg/d (2500 lb/d) of alkaline cleaning solution for reuse, which resulted in a reduction of 5-day biochemical oxygen demand (BOD5) loadings to the treatment system of 200 kg/ month (370 lb/month). This avoided the need for installation of additional treatment. 

Generally, a distinction can be made between membrane bioreactors based on cells performing a desired conversion and processes based on enzymes. In ceU-based processes, bacteria, plant and mammalian cells are used for the production of (fine) chemicals, pharmaceuticals and food additives or for the treatment of waste streams. Enzyme-based membrane bioreactors are typically used for the degradation of natural polymeric materials Hke starch, cellulose or proteins or for the resolution of optically active components in the pharmaceutical, agrochemical, food and chemical industry [50, 51]. In general, only ultrafiltration (UF) or microfiltration (MF)-based processes have been reported and little is known on the application of reverse osmosis (RO) or nanofiltration (NF) in membrane bioreactors. Additionally, membrane contactor systems have been developed, based on micro-porous polyolefin or teflon membranes [52-55]. 

Another example of using ultrafiltration for wastewater treatment and resource recovery is the separation of oil-water emulsions generated from metal machining, oil field wastes, and enhanced oil recovery effluents. Hydrophilic membranes such as cellulose acetate are preferred because they are effective barriers to oil droplets and are less prone to fouling. The UF permeate readily meets direct discharge standards. The oil-rich stream can be processed to reclaim the oil, or disposed at reduced transportation cost because of its reduced volume. 

Mobile units for photocatalytic treatment have been constructed (126,127). The European Joint Research Center laboratory pilot plant, placed on a truck, includes Ti02 loaded on membranes in UV-irradiated tubular reactors behind microfiltration and ultrafiltration modules. The waste water flow rate for this unit was typically 40 L hr-1, and hydrogen peroxide was added to the photocatalytic process (134). 

Reverse osmosis enables complete retention of aU dissolved compounds, even small monovalent ions. To avoid the membrane blocking and scaling before reverse osmosis, microfiltration, or ultrafiltration pretreatment can be applied. Apart from preliminary treatment, ultrafiltration can be used for separation of suspensions or colloids, which are often formed by actinides or ions such as " Mg, Fe, °Co, and Sb. Microfiltration found the application for waste dewatering after precipitation. Nanofiltration (NF) that uses lower pressures than reverse osmosis is applied for separation of bivalent from monovalent ions. The most common application of NF process in nuclear industry is boric acid separation from the reactor coolant. 

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