The company is located in a water-stressed region of southern Europe.
Figure 1: Fruit washing at Zuvamesa’s juice factory (Source: Zuvamesa)
One of the major water-using processes is cleaning the plant’s tanks, valves and pipes. In order to minimise water use (as well as cleaning agent use), the CIP process has been optimised through the re-use of water (and cleaning agent) in a three-step procedure:
- An initial rinse of tanks, valves and pipes with water at ambient temperature. The water used for this rinse is re-used from Step 3 (below); the wash water from this step is then sent to the wastewater treatment plant.
- A hot caustic soda treatment for 20 minutes (80 ± 5°C) – the soda solution is not discharged to the drain but instead collected and re-used in the next CIP set. Small amounts of dry caustic soda are added to the reservoir as needed, when it gets too dilute.
- A final rinse through with potable water to remove any chemical residues. This wash water is collected in a tank and re-used in Step 1.
Zuvamesa has also managed to halve the amount of chlorine used to disinfect the potable water used in Step 3 from 1 ppm to 0.5 ppm.
Other practices to reduce water used in cleaning include:
- Fruit Washer: there are three fruit washers in site and all have water recovery systems. All the fruit washers have 5 shower lines, and the water that comes out of the last shower lines is collected and reused in the first line of showers.
- Manual Cleaning process for machinery and surfaces. High pressure satellite devices are installed along the plant for cleaning with pressured water the surface of the machines. This system is more efficient and therefore important water savings are achieved.