Driving efficient life support systems at Lodz Zoo

The main challenge facing the investment project was to provide the animals with a close-to-natural environment adequate for breeding. To achieve this, the Orientarium required life support systems (LSS) to control water parameters such as purity and salinity. The LSS also needed to stabilize gas balance, and control lime and phosphate concentration for coral reef environments.

Vital processes included mechanical filtration using separators to remove mechanical impurities from the water. Another example was 2-step biological filtration using nitrification and denitrification to remove ammonia and nitrogen from the water, with the aid of aerobic and anaerobic bacteria. Other processes included disinfection via ozone and UV light, and fresh and saltwater recovery systems. Saltwater requires dilution several times before being discharged to the sewage system.

An expert team comprising architects, specialists in the field of sanitary installations and biologists prepared a requirement specification for elements of the facilities, procedures, and technologies. Based on prior experience, they estimated the number of water filtering devices required. They also designed tanks able to control gas balance by maintaining adequate levels of oxygen and carbon dioxide.

Life support systems operate thanks to pumps transporting water between installations. Each pump is equipped with a VLT® AQUA Drive FC 202 unit, to control its operation. AC drives reduce energy consumption by adjusting the power at which the pumps operate to the exact load, based on filter contamination. The lower the contamination, the lower the pressure and resistance, and hence the pump power. VLT® drives operating at the Orientarium are protected by enclosures with ingress protection rating IP55, and an anti-corrosion coating on the electronic boards.

The systems installed by Danfoss partner Transcom meet customer expectations for water purification and quality by controlling the required parameters. The pumping station systems enable reuse of fresh and saltwater from filter rinsing, to reduce water consumption. Otherwise, the daily water consumption would reach 200 m3. Residual saltwater, which cannot be recovered, is diluted with rainwater collected in underground storage reservoirs.

VLT® AQUA Drive FC 202 reduces pump load to 60-80% of maximum, generating at least 50% reduction in energy consumption compared to systems not equipped with drives.

The contractor, Transcom, prioritized reliable operation and the longest possible warranty. Midway through the 9-year period, the AC drives will be inspected by Danfoss partners.