Fluid distributor unit

1. A fluid distributor for a column, defining a distribution channel of generally conical shape defined by a circular solid back plate with a staircase pattern of at least two internal concentric annular recesses and a packed bed in the column, wherein each annular recess decreases in diameter as the staircase pattern converges towards a tube for inlet and outlet of fluid and wherein the fluid distributor comprises at least two annular fluid-permeable porous disks mounted in said annular recesses.

2. The fluid distributor of claim 1 , wherein said annular porous disks fill at least 90% of said annular recesses.

3. The fluid distributor of claim 1 , wherein the fluid distributor comprises a porous retainer disk directly facing the packed bed and at least one porous distributor disk filling the part of the distribution channel volume between the porous retainer disk and the solid back plate.

4. The fluid distributor of claim 3 , wherein each porous distributor disk has a three-dimensionally connected pore structure.

5. The fluid distributor of claim 1 , wherein a first circular or annular porous disk is concentrically fitted inside a second annular porous disk.

6. The fluid distributor of claim 5 , wherein said first and second porous disks are planar.

7. The fluid distributor of claim 5 , wherein said second porous disk has a lower thickness than said first porous disk.

8. The fluid distributor of claim 5 , wherein said second annular porous disk is concentrically fitted inside a third annular porous disk.

9. The fluid distributor of claim 1 , wherein a first circular or annular porous disk is mounted in an inner annular recess and a second annular porous disk is mounted in an outer annular recess and concentrically fitted outside said first circular or annular porous disk.

10. The fluid distributor of claim 9 , wherein said second annular porous disk has a lower thickness than said first circular or annular porous disk.

11. The fluid distributor of claim 1 , wherein a first circular or annular porous disk is mounted in an inner annular recess and a second circular or annular porous disk is mounted in an outer annular recess in planar abutment with said first circular or annular porous disk.

12. The fluid distributor of claim 1 , wherein at least one of the porous disks is welded to said solid back plate.

13. The fluid distributor of claim 1 , wherein at least one of the porous disks comprises a plastic.

14. The fluid distributor of claim 1 , wherein at least one of the porous disks comprises a porous sintered plastic material.

15. The fluid distributor of claim 1 , wherein the solid back plate comprises a plastic.

16. The fluid distributor of claim 1 , wherein the at least two circular or annular fluid-permeable porous disks are planar.

17. The fluid distributor of claim 1 , wherein a first circular or annular porous disk is mounted in an inner annular recess and a second annular porous disk is mounted in an outer annular recess and concentrically fitted outside said first circular or annular porous disk.

18. The fluid distributor of claim 17 , wherein said second annular porous disk has a lower thickness than said first circular or annular porous disk.

19. The fluid distributor of claim 1 , wherein a first circular or annular fluid-permeable disk is mounted in an inner annular recess and a second circular or annular fluid-permeable porous disk is mounted in an outer annular recess in planar abutment with said first circular or annular porous disk.

20. The fluid distributor of claim 19 , wherein a third circular or annular fluid-permeable disk can be mounted in a further outer annular recess in planar abutment with said second circular or annular porous disk.