Beet processing process and unit

A process, comprising at least the following sequence of steps consisting of:

• washing of beets;
• optional chopping and/or heating of the washed beets;
• partial pressing of the washed and optionally chopped and/or heated beets for the production, on the one hand, of a press cake of partially pressed beets containing more than 20% sugars relative to the dry matter content and, on the other hand, of a sugar juice at a concentration greater than 15% dry matter content;
• separating the press cake of partially pressed beets and the sugar juice;
• the partial pressing of the beets being the sole pressing step;
• and further comprising:
• 1) either the sequence of steps consisting of:
• filtering the sugar juice by centrifugation for the production, on the one hand, of a centrifuge cake and, on the other hand, of a centrifuged sugar juice;
• mixing the centrifuge cake with the press cake of partially pressed beets containing more than 20% sugar relative to the dry matter content, so as to obtain a mixture of a press cake of partially pressed beets with a centrifuge cake, said mixture containing more than 20% sugar relative to the dry matter content,
• 2) or the sequence of steps consisting of:
• mixing of a small percentage of flocculent, of the order of 1%, with the sugar juice so as to obtain a mixture of flocculent and sugar juice;
• membrane filtration of said mixture of flocculent and sugar juice for the production of a retentate and a permeate, said permeate providing a filtered sugar juice having a purity of at least 93%;
• and mixing the retentate with the press cake of partially pressed beets containing more than 20% sugar relative to the dry matter content, so as to obtain a mixture of a press cake of partially pressed beets with a retentate, said mixture containing more than 20% sugar relative to the dry matter content;
• 3) or the sequence of steps consisting of:
• filtering the sugar juice by centrifugation for the production, on the one hand, of a centrifuge cake and, on the other hand, of a centrifuged sugar juice;
• mixing of a small percentage of flocculent, of the order of 1%, with the centrifuged sugar juice, so as to obtain a mixture of flocculent and sugar juice;
• membrane filtration of said mixture of flocculent and sugar juice for the production of a retentate and a permeate, said permeate providing a filtered sugar juice having a purity of at least 93%;
• and
• mixing the retentate with the press cake of partially pressed beets and with the centrifuge cake containing more than 20% sugar relative to the dry matter content so as to obtain a mixture of press cake of partially pressed beets with a centrifuge cake and a retentate, said mixture containing more than 20% sugar relative to the dry matter content,
• the thus obtained mixture of a press cake of partially pressed beets with a centrifuge cake and/or a retentate, which contains more than 20% sugar relative to the dry matter content, being an easily fermentable product.