Reverse osmosis desalination plants

Evangelista, F. (1986). Improved graphical analytical method for the design of reverse osmosis desalination plants. Ind. Eng. Chem. Process Des. Dev., 25(2), 366-375. 

Co-location of a power plant and a seawater reverse osmosis desalination plant allows for the cooling water from a neighbouring power plant to be blended with the waste from a desalination plant before discharge (Voutchkov 2004). In such a process, seawater is used as the cooling water for the condensers in a power plant. This water is then used as both the feed for the desahnation process, and for blending to dilute the concentrate from the desalination plant. 

Reverse osmosis desalination plants consisting of 8 long tubular membranes prepared from commercial CA of D.S. 2.5 were set up for supply of drinking water and boiler feed water at two different locations. 

Electrical power is the energy source for RO desalination. A reverse-osmosis desalination plant is presented schematically in Figure 10.3. Electricity is used to... 

Figure 10.3 Schematic presentation of a reverse-osmosis desalination plant.

Although the integration of RO with other pressure-driven membrane processes has led to significant improvements in membrane-based desalination process economics, another fundamental problem is the environmental aspects of brine discharge from reverse-osmosis desalination plants. 

Alawadhi, A. A. (1997). Pretreatment plant design—Key to a successful reverse osmosis desalination plant, Desalination Int. Symp. Pretreatment of Eeedwater for Reverse Osmosis Desalination Plants, March 31-April 2, 110, 1-2, 1-10. Elsevier Science B.V., Amsterdam, Netherlands. 

Kiranoudis, C. T., N. G. Voros, and Z. B. Maroulis (1997). Wind energy exploitation for reverse osmosis desalination plants. Desalination. 109, 2, 195-209. 

The progress made in membrane-based desalination has lead to the substitution of evaporation plants with RO systems in different part of the world. For example, the United States holds the second position in worldwide desalination capacity (15.2% of the world production) and the 78% of their production come from RO treatments. Mediterranean countries, including Spain, Malta, Cyprus, and Israel, have also reverted from traditional multistage flash (MSF) to RO during the past two decades. The water production by reverse osmosis desalination plants passed from 36% of the global desalting capacity in 1996 to 42%... 

A further application of electrodialysis is the concentration of reverse osmosis brines. Because of limiting membrane selectivity and the osmotic pressure of concentrated salt solutions, the concentration of brine in reverse osmosis desalination plants can not exceed... 

A Figure 18.14 (a) A room inside a reverse-osmosis desalination plant, (b) Each cylinder shown in (a) is called a permeator and contains several million tiny hollow fibers, (c) When seawater is introduced under pressure into a permeator, water passes through the fiber wall into the fibers and is thereby separated from the ions of the salt. 

Catalina Island s plant may be just the beginning. The city of Santa Barbara opened a 40 million desalination plant in 1992 that can produce 8 million gallons of drinking water per day. The southern California city of Carlsbad opened a reverse osmosis desalination plant in 2012 that can produce 50 million gallons of drinking water daily from seawater. Desalination plants are also in the woiks for Huntington Beach, California, and Camp Pendleton, a military base just north of Carlsbad. 

Applications - Electricity - Seawater desalination (CAREM could supply heat or electric eneigy for a reverse osmosis desalination plant) - Electricity plus potable water or - Electricity plus district heating or - 80 - 100 MW(e) of electricity and water or steam at — 100°C for food industry (conservation industry)... 

FIG. VII-15. Principal flow diagram of the power-desalination complex with a condensing turbine and a reverse osmosis desalination plant... 

Mass transfer in the entry region is far from a rare event Transport in the larger blood vessels lies entirely in the entry region, and so does mass transfer in commercial reverse osmosis desalination plants and other membrane processes (see Chapter 8). Entry lengths of many meters are not uncommon, particularly for low-solute dilfusivities. The only requirement is that flow must be in the laminar regime (Re < 2(XX)). 

Ahmed, M., Shayya, W. H., Hoey, D., and Al-Handaly, J. (2001). Brine disposal fiom reverse osmosis desalination plants in Oman and the United Arab Emirates. Desalination 133, 135-147. Alborzfar, M., Escande, K., and Allen, S. J. (1998). Removal of namral organic matter from two types of humic ground waters by nanofiltralion. Water Res. 32(10), 2983-2970. 

The membrane processes are characterized by quite small flow channels in and through the modules. This means that adequate prefiltration must be employed, in order to ensure as long a life as possible for the final separation stage. It is not uncommon now to find, for example, an ultrafiltration plant (with its own inlet microfilters) being used as a prefilter for a reverse osmosis desalination plant, as illustrated in Figure 2.25. 

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