Ultrapure water power industry

Gunnerson, Gary. Using Activated Carbon for Pretreatment in the Power Industry. Ultrapure Water, Tall Oaks Publishing, Inc., USA, October 1998. 

Approximately one-half of the reverse osmosis systems currently installed are desalinating brackish or seawater. Another 40 % are producing ultrapure water for the electronics, pharmaceutical, and power generation industries. The remainder are used in small niche applications such as pollution control and food processing. A review of reverse osmosis applications has been done by Williams et al. [52],... 

The pharmaceutical industry lead the way in adoption of CEDI for the production of ultrapure water. Since the early 1990 s, the power industry has been employing CEDI as a polisher for RO effluent for steam generation. Other industries currently using CEDI include general industry for boiler make-up or high-purity process applications, including semiconductor manufacture. Commercially-available industrial CEDI modules range in size from less than 1 gpm to 80 gpm. 

Ion chromatography is frequently used to determine anions and cations at very low concentration levels, often in the low xg/L (ppb) range. In the electric power industry the water used in steam generators must be almost free of Na", Cl" and other ions to avoid stress corrosion cracking. The ionic content of ultrapure water used in the electronics industry must be kept to extremely low levels. Semiconductor chip manufacturers require clean-rooms with utility impurities of no more than 1 ppb for 0.35 pm devices [1]. 

In the case of water treatment, it can be stated that cuirent technologies concerning photocatalyzed oxidative degradation processes can be considered as practical alternatives to existing wastewater treatments. Photocatalysis has already found applications in small to medium sized units in the treatment of contaminated ground waters and in the production of ultrapure water for pharmaceutical and micro electronic industries (Crittenden et al., 1997 Nogueira and Jardim, 1996 Parent et al., 1996). Relevant application examples to be cited are the solar-powered 300-liter/hour capacity solar unit in Almeria, Spain (Blanco et al., 1996a Minero et al., 1996) and the 60-6000 liter/hour units commercialized by Purifies (Butters and Powell, 1995). 

S. Judd, B. Jefferson, Industrial effluent recycling in the power indiastry, Ultrapure Water 21 (4) (2004) 37-42. 

Membrane-based technologies have become the industry standard for the ultrapure water systems in the semiconductor, pharmaceutical, and power industries. The seminal discovery that changed membrane separation from a laboratory to an industrial process was the development, in the early 1960s, of the Loeb-Sourtrajan process for making defect-free, high-flux, anisotropic reverse osmosis membranes (Loeb and Sourirajan, 1963). The most important development in the 1980s was the innovation of industrial membrane gas separation process. 

Figure 13.3 T3fpical ultrapure water system in the power industry.

---