The purification cartridge packs in the Cascada BIO- and AN-water Systems are designed to provide the maximum output of water before they need to be changed. Due to the unique multi-stage monitoring system, the purification cartridge pack in the primary position can be used until its product water quality has dropped to 1 Mohm-cm while still maintaining a quality of 18.2 Mohm-cm in the product water. This is due to the polishing purification cartridge pack connected in series after it.

Table 1
Purification Cartridge Pack Capacity on Different Feed Waters

Examples of capacity test data are shown with different types of feed water and typical results are listed. The calculated capacity in liters of water of each purification cartridge pack with a conductivity of 1 µS/cm at pH 7 based on this data is listed above.

The purification cartridge pack capacity in liters of water produced will depend on the total ionic loading of the feed water and the ratio of anion to cation load. In a deionized feed, these will be approximately equal. In a feed of reverse osmosis (RO) permeate, there is often a high level of dissolved carbon dioxide that is not rejected by RO membranes. Carbon dioxide is removed on anion resin as bicarbonate or carbonate ions and so increases the anion load on the cartridge pack relative to the cation. The proportion of resins in the PAL-LC147 Cascada BIO- and AN-water Systems purification cartridge pack are adjusted to provide increased anion capacity. The packs have been tested on RO permeates of different qualities and with a sodium chloride feed, prepared by dissolving sodium chloride in ultrapure water.

Figure 1
Product Resistivity Profile of Cascada BIO- and AN-water Systems Pack, Feed: NaCI, 37 µS/cm, 1.8 L/min

Figure 2
Product Resistivity Profile of Cascada BIO- and AN-water Systems Pack, Feed: 32.5 µS/cm, 4 ppm CO₂

Figure 3
Product Resistivity Profile of Cascada BIO- and AN-water Systems Pack, Feed: 14.7 µS/cm, 19 ppm CO₂