Village LW-160, Руководство пользователя и справочное руководство

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GENERAL THEORY
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VMT- v. JUNE 2008
pressure on the unit above the recommended range) results in greatly increased membrane fouling
rates and a significant decrease in the operational life of the membranes.
It should be noted that no system is capable of removing all 100% of the dissolved solids from
seawater. Designed to reject approximately 99% of the TDS, the system allows 1% of the 32,000 ppm
TDS in the seawater to pass into the product water. This yields product water of less than 500 ppm, the
recommended TDS for drinking water. A system such as this is said to have a
salt passage of 1%.
Figure 3.: Simplified Schematic of an RO System.
3.3 PRODUCT WATER QUALITY STANDARDS
This RO unit will produce permeate (product water) with a quality of less than 500 ppm TDS and in
accordance with World Health Organization (WHO) guidelines for drinking water. General WHO
specifications for acceptable drinking water quality are as follows:
Table 3.0 - WHO Drinking Water Guidelines.
Constituent Ion / Molecule Maximum Limits (ppm)
Nitrate 10
Fluorine 1
Chlorine 250 (per USPHS 1962)
Sulfate 100
Magnesium 30
Calcium 75
Calcium Carbonate 100
Iron 0.1
Manganese 0.05
Total Dissolved Solids 500
Turbidity 5
Oil 0.1
Detergents (Anionic) 0.2
Phenols 0.001
Bacteria – E. Coli (per 100 ml) 0