Granted Patent B2

US 12,722,994 · App. 18/549,066 · Granted Sep 1, 2026

Inventors: Mathieu Haddad (Sevres, FR); Valéry Geaugey (Paris la Defense Cedex, FR); Cynthia Berlou (Paris la Defense Cedex, FR); Manuel Lipp (Ellwangen, DE); Pedro Benard Guedes Lopes Da Fonseca (São Domingos de Rana, PT)

Assignees: SUEZ INTERNATIONAL; XL BETEILIGUNGEN GMBH & CO. KG

C02F11/04C02F3/08C02F3/2866C12M1/107C12M21/04C12M29/18C12M41/02C12M41/44C12M47/18C02F2301/046Y02E50/30

Abstract

Claims (34)

1 . A digester adapted to perform a sludge methanization treatment for generating biogas and a digestate, the digester comprising:

an enclosure adapted to contain a volume of material, the volume of material comprising the digestate, the digestate comprising, at a surface, at least foaming or floating matter coming from sludge or generated during the methanization treatment, the enclosure defining a first volume equal to the volume of material and a second volume arranged above the first volume;

a roof adapted to close the enclosure;

a reservoir near the enclosure and adapted to collect the digestate;

a dome arranged on a portion of the roof and adapted to collect the biogas;

a device for discharging the at least foaming or floating matter comprising:

a first tank arranged in the enclosure, the first tank being submerged in the volume of material and delimited by a first wall, the first tank being adapted to be fed with the digestate and with the at least foaming or floating matter from the volume of material by overflow over the first wall;

a second tank connected to the atmosphere and sited outside the enclosure, comprising:

a first zone delimited by a second wall; and

a second zone in communication with the reservoir;

a conduit that connects the first tank via a first orifice to the first zone of the second tank via a second orifice, wherein

the first zone is adapted to be fed with the digestate and with the at least foaming or floating matter from the first tank through the conduit,

the second zone of the second tank is adapted to be fed with digestate from the first zone of the second tank by overflow over the second wall,

the second orifice is positioned higher than or level with the first orifice,

an upper end of the first wall is located at a first height above a reference point of the first orifice and an upper end of the second wall is located at a second height above the reference point of the first orifice and the upper end of the second wall is positioned lower than the upper end of the first wall,

the first height and the second height are predefined based on a ratio between a first average density of a first mixture, containing variable proportions of the digestate and the at least foaming and/or floating matter in the first tank that is transferred by gravity into the first zone and a second average density of a second mixture containing variable proportions of the digestate and the at least foaming or floating matter in the first zone.

2 . The digester according to claim 1 , further comprising a device for mixing the volume of material disposed in the first volume, the mixing device being configured to move the volume of material.

3 . The digester according to claim 2 , wherein the mixing device comprises:

one or more chimneys extending into the enclosure along a first axis, each chimney having an upper end and a lower end;

one or more first mixers, the one or more first mixers(s) being configured to move the volume of material in rotation around a vertical central axis, substantially parallel to the first axis, and in translation along the first axis from the upper end toward the lower end of said one or more chimneys.

4 . The digester according to claim 2 , wherein the mixing device comprises one or more second mixers, each being arranged in the enclosure, the second mixers being configured to move the volume of material in rotation around a vertical central axis, substantially parallel to the first axis.

5 . The digester according to claim 1 , further comprising a device arranged in the volume of material for injecting the digestate into the second volume.

6 . The digester according to claim 5 , wherein the digestate injection device comprises:

a first injector attached to the roof and in fluid connection with the second volume and configured to inject digestate into the second volume;

a first recirculation loop between the first volume and the first injector;

a first recirculation pump configured to recirculate the digestate in the first recirculation loop from the first volume to the first injector.

7 . The digester according to claim 5 , wherein the digestate injection device further comprises:

a second injector attached to a side wall of the enclosure at a first height and in fluid connection with the enclosure and configured to inject digestate into the enclosure at the first height;

a second recirculation loop between a second height of the enclosure, which is less than the first height, and the second injector;

a second recirculation pump configured to recirculate the digestate in the second recirculation loop from the second height of the enclosure and to the second injector.

8 . The digester according to claim 7 , wherein the first recirculation loop ( 30 ) and the second recirculation loop are grouped into one and the same recirculation loop, the first recirculation pump and the second recirculation pump forming a single recirculation pump configured to recirculate digestate to the first injector and/or to the second injector.

9 . The digester according to claim 1 , wherein the roof is made of metal.

10 . The digester according to claim 1 , where a first product of the first average density times the first height is greater than a second product of the second average density times the second height.

11 . The digester according to claim 1 , wherein the second average density is greater than the first average density.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (17)