Power membrane

T. Shimohira, Y. Saito, K. Saito and H. Miyake, Design and future of Fx-50 membrane A membrane for production of 50% caustic soda, Rep. Res. Lab. Asahi Glass Co., Ltd, 1993, 43, 119-128 J.D. Powers, Membrane electrolysis process for producing concentrated caustic. USPat. 4,900,408, 1990 T. Hiyoshi and A. Kashiwada, Fluorinated cation exchange membrane, Jpn. Pat. JP 5-222220 (unexamined application). 

J. Blanco Galvez, L. Garcfa-Rodrfguez, I. Martm-Mateos, Seawater desalination by an innovative solar-powered membrane distihation system The MEDESOL project. Desalination 2009, 246, 567-576. 

Schafer AI, Hughes G, Richards BS. Renewable energy powered membrane technology a leapfrog approach to rural water treatment in developing countries Renew Sustain Energy Rev... 

Reverse osmosis Liquid solution Pressure gradient (pumping power) + membrane Two liquid solutions Different combined solubilities and diffusivities of species in membrane Sea water desalination 18, 44-46... 

Rossiter, H.M.A., Graham, M.C. Schafer, A.I. (2010) Impact of speciation on behaviour of uranium in a solar powered membrane system for treatment of brackish groundwater. Separation and Purification Technology, 71 (1), 89-96. 

Richards, L.A., Richards, B.S. Schafer, A.I. (2011) Renewable energy powered membrane technology salt and inorganic contaminant removal by nanofiltration/reverse osmosis. Journal of Membrane Science, 369, 188-195. 

Figure 4.8. Solar powered membrane filtration system for uranium removal (adapted from Rossiter et al, 2010) where P = pressure gauges Pl-3 = pressure transducers Fl-2 = flow sensors VI = pressure relief valve V2 = pressure control valve GPS = solar tracker guided by global positioning system and MPPT = maximum power point tracker.

Table 4.8 provides the complete operation and maintenance cost of RO system, which includes power, membrane module and micron filter cartridge re-plaeement costs, chemical consumption for cleaning and storage, etc. Feed capacity and recovery were assumed to be 2 m /h and 60%, respectively. The operational time for system was assumed to be 10 h per day in view of the fact that electric power supply in remote villages is restricted to a few hours per day. Depreciation costs were taken as 10% of the total capital investment while life of hardware is expected to be 10 years. Membrane life was foimd to be 3 years as per data collected at village sites where plants have been operated. 

Saffarini, R.B., E.K. Summers, H.A. Arafat, and J.H. Lienhard. 2012a. Economic Evaluation of Stand-alone Solar Powered Membrane Distillation Systems." Desalination 299 55-62. doi 10.1016/j.desal.2012.05.017. 

The method has severe limitations for systems where gradients on near-atomic scale are important (as in the protein folding process or in bilayer membranes that contain only two molecules in a separated phase), but is extremely powerful for (co)polymer mixtures and solutions [147, 148, 149]. As an example Fig. 6 gives a snapshot in the process of self-organisation of a polypropylene oxide-ethylene oxide copolymer PL64 in aqueous solution on its way from a completely homogeneous initial distribution to a hexagonal structure. 

Lithium peroxide is a strong oxidizer and can promote combustion when in contact with combustible materials. It is a powerful irritant to skin, eyes, and mucous membranes (2) protective clothing should be worn when handling lithium peroxide. The LD q has not been deterrnined, and there is no designated threshold limit value (TLV). However, 5 g of many lithium compounds can be fatal. 

CSM is extensively used in constmction and electrical appHcations. This includes roofing membranes, automotive ignition boots and wire, toU compounds, and in some automotive hoses requiring good heat and oil resistance, eg, air conditioning and power steering. It is also used in nuclear power plants because of its exceUent resistance to radiation degradation. 

Electrodialysis. Electro dialytic membrane process technology is used extensively in Japan to produce granulated—evaporated salt. Filtered seawater is concentrated by membrane electro dialysis and evaporated in multiple-effect evaporators. Seawater can be concentrated to a product brine concentration of 200 g/L at a power consumption of 150 kWh/1 of NaCl (8). Improvements in membrane technology have reduced the power consumption and energy costs so that a high value-added product such as table salt can be produced economically by electro dialysis. However, industrial-grade salt produced in this manner caimot compete economically with the large quantities of low cost solar salt imported into Japan from Austraha and Mexico. 

Constmction of new power plants in the coal region of the western United States presents serious problems in states whose laws dictate zero effluent. In these plants, cooling-tower water withdrawn from rivers cannot be returned to them. In these situations, cooling-tower effluent is purified by distillation (vapor-compression plants have predominated) and by a combination of distillation and membrane technology. The converted water then is used as boiler feedwater the plant blowdown (effluent) is evaporated from open-air lined pools, and pool sediment is periodically buried back in the coal mine with the flue ashes. 

The voltage used for electro dialysis is about 1 V per membrane pair, and the current flux is of the order of 100 A/m of membrane surface. The total power requirement increases with the feedwater salt concentration, amounting to about 10 MW per m product water per 1000 ppm reduction in salinity. About half this power is required for separation and half for pumping. Many plant flow arrangements exist, and their description can be found, along with other details about the process, in References 68 and 69. Many ED plants, as large as 15,000 vsf jd, are in operation, reducing brackish water concentration typically by a factor of 3—4. 

Powerful solvents such as dimethyl sulfoxide (common laser dye solvent) and solubilizing substituents (K" and R " = sulfoalkyl in stmcture 32) may enhance the transport of dyes in solution through skin and other membranes. Reference 88 (on laser dye solutions and toxicity) is recommended to researchers working with dye solutions. Other dyes, such as Indocyanine Green, attain useful properties (blood tracer dye) as a result of having solubilizing substituents in their stmcture. 

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