A packed tower for the absorption of water or SO 3 in sulfuric acid includes a jacket and a domed grid disposed within the jacket. The domed grid is held on an L-shaped ring such that a gap is formed between an outside diameter of the domed grid and the jacket. A bed of packings is held on the domed grid through which the sulfuric acid charged from above trickles. A gas supply tube is disposed in a lower region of the tower. A gas outlet is disposed above the bed. An acid outlet is disposed in the lower region of the tower.
1. A packed tower for the absorption of water or SO 3 in sulfuric acid, the packed tower comprising:
a jacket;
a domed grid held on an L-shaped ring such that a gap is formed between an outside diameter of the domed grid and the jacket;
a bed of packings held on the domed grid and configured to have sulfuric acid charged from above trickle therethrough;
a gas supply tube disposed in a lower region of the tower;
a gas outlet disposed above the bed; and
an acid outlet disposed in the lower region of the tower.
2. The packed tower according to claim 1 , wherein the L-shaped ring includes two legs of different materials.
3. The packed tower according to claim 2 , wherein one of the two legs is a substantially horizontally arranged leg substantially made of Si-free stainless steel.
4. The packed tower according to claim 2 , wherein one of the two legs is a substantially vertically arranged leg made of stainless steel with an Si content of 4.5 to 6.5 wt-%.
5. The packed tower according to claim 1 , wherein an outside diameter of the L-shaped ring is smaller than an inside diameter of the packed tower by about 20 to 200 mm.
6. The packed tower according claim 1 , wherein the L-shaped ring rests on vertical supporting plates.
7. The packed tower according to claim 6 , wherein the supporting plates are disposed a distance of 500 to 2500 mm from each other.
8. The packed tower according to claim 6 , wherein the supporting plates are made of stainless steel with an Si content of 4.5 to 6.5 wt-%.
9. The packed tower according to claim 1 , further comprising an apron disposed around a lower region of the gas supply tube, the apron having at least one of holes and a slot through which the acid can pass.
10. The packed tower according to claim 9 , wherein the apron is inclined upwards from the jacket of the packed tower towards an opening of the gas supply tube, and wherein the slot is disposed in a region of the apron facing the gas supply tube.
11. The packed tower according to claim 2 , wherein the two legs are connected to each other by a weld.
12. The packed tower according to claim 6 , wherein the supporting plates are uniformly distributed around a circumference of the tower.