MB/MBA mixed bed - Silhorko-Eurowater A/S - #2

AUTOMATIC MIXED BED PLANT

Applicable for polishing of demineralized water that is produced in an automatic two-column plant or in a reverse osmo­sis plant. Also applicable for production of moderate quantities of demineralized high-quality water direct from the wate­rworks.

The electronic 12 V control panel conta­ins a conductivity meter and control and program sections. The panel has battery back-up in case of interrupted power supply and output for remote alarms is available.

A mixed bed plant for polishing of demi-neralized water has a very large capaci­ty. The basic capacity is stated in valen­ce per regeneration. The actual capacity is calculated by dividing the basic capa­city by the total salt content of the feed-water in valences.

The conductivity meter continuously indicates the quality of the treated water in microSiemens (uS/cm.). The lower the conductivity - the purer the water. The water quality is supervised by an adju­stable alarm that also can transmit rege­neration impulse.

Treatment of demineralized water with low carbonic acid content results in con­ductivities as low as under 0.1 uS/cm. at 10°C. This demands regenerations with demineralized water. If the silica content is to be as low as possible, it is neces­sary to heat the regeneration water.

The plant contains a mixture of cation and anion exchangers that are regene­rated with hydrochloric acid and sodium hydroxide, respectively. When the water passes through the regenerated ion exchangers the cations and the anions are exchanged for hydrogen and hydroxyl ions, thus producing demineral-ized water with an extremely low condu­ctivity.

Choice between timer, meter, or quality control is available on the control secti­on. The program section has sixteen time adjusted regeneration cycles. All regeneration and operational conditions can be followed via the light-emitting diodes.

Admission of ordinary clean waterworks water with moderate salt content will result in demineralized water with con­ductivities that are lower than those in water from both two-column plants and reverse osmosis plants. Softened or demineralized water is used for the regeneration.

The regeneration starts with a separati­on of the two exchangers. Then follows a regeneration with hydrochloric acid and sodium hydroxide. After various rinses the two ion exchangers are again mixed by means of compressed air. The durati­on of a regeneration is 372-4 hours.

For continuous operation two mixed bed plants can be controlled so that one of the plants always is in service. When the capacity is exhausted the plant is rege­nerated and is then on stand-by while the other plant is in service.

Acid and caustic are drawn direct into the plant by ejectors. The chemicals can be drawn direct from the original chemi­cal containers or from special acid and caustic tanks. The acid and alkaline water from the regeneration are neutral­ized according to the regulations in force pertinent to waste water.

The resin tank is surface treated with high density polyethylene making it absolutely free of pinholes. The dielect­ric strength is approx. 21 kV/mm. Pipes and automatic valves are made of plasti­cs.

The marketing of the plants also compri­ses a version with manual regeneration.

(1) Dimensioned sketch with the exact installation dimensions is available.

Printed in Denmark . Industri-Trykkeriet Ärhus A/S