By the skillful use of pressure control valves, which regulate the inert gas pressure in a tank within a precisely defined scope (up to 5 mbar), many tank plants follow a very simple principle. Small set pressure -> low nitrogen flow -> reduced loss of the expensive gas whilst the protective function is maintained!
From the new to the old world. Fermentation of direct juice poses an unanticipated problem to tank inertisation
There is rather no other drink than the juice of oranges that refreshes and delights people all over the world. However, only a few know something about the troublesome journey of the round fruit from the plantation to our local supermarket.
Brazil in South America is one of the world’s largest producer and supplier of the citrus fruit. By sea routes the oranges reach their destination Europe where they are further processed, predominantly in Italy. It is a widespread problem of this industry that these deeply dyed-in-the-wool landlubbers get seasick, a fact which makes their sweet taste bitter overnight.
Unexpected sudden fermentation of the concentrated juice makes tank walls corrode and eats away prospects of profit
Oranges are often not transported as whole fruits but in liquid form as direct juice or concentrated juice. Particularly direct juices are exposed to detrimental influences during their long journey to Europe which may lead to fermentation, perishing and also to production downtime in the end. A major reason for the sudden perishing of the goods is unwanted oxygen in the storage tank. If the citric acid reacts with the oxygen, not only the tank content may spoil completely but the transport tanks themselves may be damaged because sudden oxidation accelerates their corrosion significantly.
Caution goes before deterioration. Control accuracy and reduction ratio are essential!
There are indeed solution approaches to avoid corrosion and perishing. One option would be the use of nitrogen which is filled as inert gas into the tank and drives out the oxygen thus preventing oxidation. However, nitrogen remains an expensive gas, therefore the pressure range as well as the constant regulation of the gas are important parameters. Consequently, overpressure in the tank means that the gas must be discharged and is wasted in the atmosphere. Small quantities of the expensive gas also evaporate in regulators with manometer connections, the invested money is literally squandered away. With an average price of 35-45 Euro for 50 litres of industrial nitrogen, even small quantities of wasted gas make themselves felt. Therefore, a small pressure range to regulate the inert gas is recommended.
Long last is finally good. Of reduced risks, constant regulators and rising profits
By means of a clever combination of nitrogen and self-acting control valves the juice can be protected from perishing over the long term. In addition, the transport tank has a significantly longer service life thanks to the reduced risk of corrosion. Production costs can be reduced whilst earnings are boosted sustainably. Lastly, such accents in the production ensure a sweet outcome for all parties involved in the business with the round fruit.
Image source: Daniel Ernst/stock.adobe.com