Sludge dewatering device
Sludge dewatering device that makes it possible to achieve a high degree of dryness while retaining a limited energy consumption and limited industrial risks, comprising at least one first plate ( 21 a ) equipped with a first electrode ( 23 a ), and at least one second plate ( 21 b ) equipped with a second electrode ( 23 b ), wherein the first and second plates ( 21 a, 21 b ) define a chamber ( 22 ) configured for receiving a sludge to be dewatered ( 10 a ), wherein the first and second electrodes ( 23 a, 23 b ) are configured for establishing an electric field within the chamber ( 22 ), wherein the chamber ( 22 ) is equipped with at least one discharge port ( 32, 34 ), provided in the bottom third of the chamber ( 22 ), configured for discharging a filtrate ( 15 a, 16 a ), and wherein the chamber ( 22 ) is equipped with at least one injection port ( 33 ), provided in the top third of the chamber ( 22 ), configured for injecting the pressurized purge fluid ( 11 a ) into the chamber ( 22 ).
1. A sludge dewatering device, comprising
a first plate equipped with a first electrode;
a second plate equipped with a second electrode, at least one of the first plate and the second plate equipped with a filter; and
a supply of a pressurized purge fluid, the pressurized purge fluid comprising a gas,
wherein the first and second plates define a chamber configured for receiving a sludge to be dewatered,
wherein the first and second electrodes are configured for establishing an electric field within the chamber,
wherein the chamber is equipped with:
at least one discharge port, provided in the bottom third of the chamber, configured for discharging a filtrate from the filter, and
at least one pressurized purge fluid injection port, provided in the top third of the chamber, connected to the supply of pressurized purge fluid for injecting the pressurized purge fluid into the chamber, the at least one pressurized purge fluid injection port being connected to the at least one discharge port via the chamber.
2. The device as claimed in claim 1 , wherein each of the first plate and the second plate is equipped with at least one of the discharge ports, and
wherein each of the first plate and second plate is equipped with at least one of the pressurized purge fluid injection ports.
3. The device as claimed in claim 2 , wherein said at least one discharge port of the first plate and said at least one discharge port of the second plate are connected to different discharge channels, and
wherein said at least one pressurized purge fluid injection port of the first plate and said at least one pressurized purge fluid injection port of the second plate are connected to different injection channels.
4. The device as claimed in claim 1 , further comprising:
a supply of a second purge fluid, the second purge fluid being different from the pressurized purge fluid,
wherein the first plate is equipped with the at least one pressurized purge fluid injection port, and
wherein at least one of the first plate and the second plate is equipped with at least one second purge fluid injection port, provided in the top third of the chamber, connected to the supply of second purge fluid for injecting the second purge fluid into the chamber.
5. The device as claimed in claim 1 , wherein the pressurized purge fluid supplied from the supply comprises the gas or a mixture of gases that is/are inert, nontoxic, nonflammable and unable to create an explosive zone in the presence of H 2 or O 2 .
6. The device as claimed in claim 1 , wherein the pressurized purge fluid supplied from the supply is moistened.
7. The device as claimed in claim 1 , wherein the pressurized purge fluid supplied from the supply comprises at least one electrolyte.
8. The device as claimed in claim 7 , wherein the at least one electrolyte supplied from the supply comprises a compound containing the element chlorine.
9. The device as claimed in claim 1 , wherein the pressurized purge fluid supplied from the supply is sulfate-free.
10. The device as claimed in claim 1 , wherein the pressurized purge fluid supplied from the supply comprises at least one acid.
11. The device as claimed in claim 1 , wherein the pressurized purge fluid supplied from the supply comprises at least one base.
12. The device as claimed in claim 1 , comprising at least one liquid/gas separator provided downstream of said at least one discharge port.
13. The device as claimed in claim 5 , wherein the pressurized purge fluid supplied from the supply is selected from the following gases: N 2 , He, Ar, CO 2 , air or a mixture thereof.
14. The device as claimed in claim 7 , wherein the pressurized purge fluid supplied from the supply comprises at least one electrolyte selected from the following species: NaCl, KCl, Na 2 SO 4 or K 2 SO 4 .
15. The device as claimed in claim 10 , wherein the pressurized purge fluid supplied from the supply comprises HCl.
16. The device as claimed in claim 11 , wherein the pressurized purge fluid supplied from the supply comprises NaOH.