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5. PRETREATMENT BY SCREENING
3,000
Construc􏰀on Cost (in US$1,000 )
1,000
0
2,000
FIGURE 5.8
Construction costs for wedge-wire screens.
FIGURE 5.9
Self-cleaning microstrainer.
0
40,000 80,000 1,20,000 1,60,000 2,00,000 2,40,000 2,80,000 3,20,000 3,60,000 4,00,000
Desalina􏰀on Plant Intake Flow Rate (m3/day)
groove below, creating a filtration element with series of valleys and traps for source water debris. The stack is enclosed in corrosion- and pressure-resistant housing.
Desalination plants with disk filter microscreens are usually also equipped with conven- tional coarse screens or a combination of coarse and fine screens, which retain debris larger than 10 mm (0.4 in.). During the filtration process, the filtration discs are tightly compressed together by the spring’s power and the differential pressure, thus providing high filtration efficiency. Filtration occurs while water is percolating from the peripheral end to the core