Starch recovery is interesting for manufacturing processes that lose starch to water by rinsing or cleaning. Reclaiming the starch from that wastewater is a cost effective way to recover a valuable product. On top of it, it reduces the BOD/COD content from the effluent, reducing trade waste.
Potatoes or other roots or tubers that are peeled, sliced or cut, are normally rinsed off with fresh water before the next process step. Significant starch concentrations in the plant’s wastewater flows accumulate and flow to the plant’s waste water treatment or discharged to sewer. Starch recovery is most beneficial close to the origin of the source as no to minimum contamination takes place.
A decanter centrifuge or a filter press are both suitable mechanical dewatering technologies to increase the starch concentration. As the (re)processing of the reclaimed starch cake takes place without addition of sulphur dioxide, micro organisms which abound in the water immediately attack the solids. For that reason the wet starch cake requires almost instant drying. Heating of the hot air can be for instance by natural gas, LPG, steam and most other heat carriers. Ingetecsa can re-use available waste energy to integrate in the drying plant for a further reduction of operational expenditures.
Starch recovery plants are gaining popularity. Often the manufacturing process can re-use the starch. Selling the starch as a high end product is a possibly lucrative alternative possibility. So long the starch finds its way back in a process, the payback time of a recovery plant is going to be short.
Read more about native starch drying here.