REVERSE OSMOSIS

The reverse osmosis (RO) is not a new process, it is commonly used for water production or in household installations for its treatment. However, in fruit juice thickening plants it is a very rarely used process. That’s too bad As shown by the semi-technical tests conducted by us in one of the RO plants, it works well at the initial stage of water extraction.

In the entire thickening process we evaporate approx. 85% of the water from the juice. For example, apple juice from the press has 10Bx while concentrated apple juice 70BX. Generally, most plants use multi-division evaporation stations for this purpose, which are inefficient. The heating medium is steam and mainly fine coal or gas is used to produce it. The cost of evaporation of 1m³ of water in such technology is approx. EUR 9.

Using RO, you can successfully concentrate the juice from 10Bx (or of course below) to 18Bx. And this represents 50% of the total water we extract in the process. The cost of extraction of 1m³ of water per RO is approx. EUR 1,2.

Now, assuming that a medium-sized plant processing 1000 tons of apples per day must extract/evaporate 760 m³ of water, the cost is approx. EUR 6840. Using RO, the costs will be 380m³ * EUR 1,2 = EUR 456 + 380m³ * 9 = EUR 3,420 total EUR 456 + EUR 3,420 = EUR 3,876, i.e. EUR 2,964 less for each day of production. On average, the plant produces approx. 110 days a year, which gives EUR 326,040

Apart from all ecological aspects of such production, it seems that economics will be a decisive factor in changing the attitude of plants towards this technology.