Food waste treatment
Food waste is defined as edible raw or cooked substances that are no longer destined for consumption. Food waste can be thrown away but can also be used to feed animals or be disposed of via biodegradation, through the compost or anaerobic digestion methods, to then be reused as fertilisers. The anaerobic digestion method involves the degradation of organic matter using micro-organisms. This process starts with the removal of undegradable material and subsequent grinding of the pieces that must be treated. After being placed in special reactors, the materials are mixed with bacteria and brought to set temperatures. Biogas, which can be used as an alternative energy source, is produced through this process. On the other hand, the material coming out of the reactor is a liquid sludge that must be dehydrated using a screw press.
Screw press for food waste
The screw press for food waste is a slow-moving mechanical device in which a conical screw rotates inside a perforated cylindrical filter or one made of wedge wire screen. During the pressing phase, the liquid sludge is pressed with increasing force against the metal filter. The holes or openings in the filter allow the water to drain out. The water removed is collected and undergoes purification treatment. The remaining sludge is stabilized, refined and used as fertiliser.
In food waste treatment, the Costacurta drilled plate or VICO-screen (which forms the filter of the screw press) is a fundamental element of the machine. The filter element must have high mechanical strength and small open areas to make the filtration of the water possible and to separate it from the solid part.
Distinctive characteristics of the Costacurta filter elements for screw presses for food waste are:
- High quality of the materials
- Precision of the production process