DE102006009105B3 - Honeycomb structure for smoke gas sulfur washing tower has a base layer with drain holes resting on base slats - Google Patents

Abstract

A smoke gas sulfur washing tower has a stack of honeycomb panels (1) whose lowest section rests on slats (5). The honeycomb side panel in contact with the base slat has drain holes (2). The uppermost honeycomb section has right angled lip covers (4) over the gaps to the adjacent honeycomb sections. The adjacent zone has a recess (6) for a right-angled lip from the adjacent honeycomb stack. The lip (4) has the same width and thickness as the recess (6) and covers the vertical gap (3) under all operating conditions. The wet film contact structure is formed by a stack of honeycomb panels with levels discharging to the drain holes (2). The number of drain holes is such that the stability of the stack is adequate, that the vertical gap (3) has good drainage properties, and that the drain holes within adjacent honeycomb layers are transposed with respect to each other.

Description

The Invention relates to a washing tower, in particular for a flue gas desulphurisation plant, with a wet film contact structure formed in one or more layers made of honeycomb.

to Achieving a pronounced Interaction between gases, vapors or gas-steam mixtures and liquids are wash towers, Reaction towers scrubbers, Absorber towers, Mass transfer columns and the like. In various embodiments, both in the chemical industry as well as in power plant engineering. For example flue gases from steam generator plants are used to remove it contained sulfur dioxide subjected to a wet flue gas scrubbing. It is known that the flue gas in the lower part of an absorber flows and when ascending within the absorber with one of an absorbent (e.g., limestone, lime, chalk) is sprayed. In the contact zone, the sulfur components by chemical Reaction bound with the calcium carbonate. A reaction product the chemical reaction is gypsum, which as a product further use, z. B. in the construction industry, finds.

to Improvement of the degree of separation of the sulfur dioxide is still known, below spray nozzles, which in several levels of the absorber z. B. a limestone suspension introduce an effective wet film contact.

This happens often by means of multi-layer grid layers (wet film contact structure). In order to will be a big one contact surface generated an improved response of the limestone suspension and of sulfur dioxide. Also at reactor towers in the chemical industry are used to increase reaction areas and Equalization of gas flows single or multi-layer grid layers used.

One serious problem with such grid situations is their relative fast pollution between grid packages in the vertical Columns. These contaminants lead often by growing up to volume expansions and as a result for deformation of the grid packages.

From the DE 100 25 061 C1 An absorber for flue gas desulphurisation systems has become known. A wet film contact structure of two grid layers is arranged between a lower flue gas inlet and an upper flue gas outlet. Substantial costs arise when operating such a flue gas desulfurization plant due to the rapid holistic pollution of the grid layers. However, their costly replacement is absolutely necessary after a certain period of operation due to the pollution.

to solution This problem is proposed, the grid-like absorber structure form thicker in the region of the center axis of the absorber than in their outer area adjacent to the wall of the absorber, wherein the thickness of the absorber structure from the central axis of the absorber to her outdoor area gradually or gradually decreases.

Thereby intended to improve the velocity distribution of the flue gas flow, which mainly centered, and consequently a reduction pollution.

Now, however, the operation of such flue gas desulfurization systems has revealed a further disadvantage of the grid positions, which is not achieved with the aid of the invention DE 100 25 061 C1 can be solved.

Grid positions be z. B. of several adjacent rectangular honeycomb, consisting of a plastic (eg polypropylene), formed. there grips the surrounding outer wall the rectangular honeycomb flat arranged cavities a, the z. B. hexagonal, cylindrical or cuboid, wherein the outer wall the honeycomb and the walls the cavities in the flow direction aligned the flue gas. The grid layer fills the entire cross section from the wash tower. It can also several layers arranged one above the other be. Between the honeycomb vertical gaps are formed. To the Honeycomb-to-honeycomb seams, which rest on carriers, penetrate absorber suspension one, which can not run down. This particle-enriched Absorber suspension vaporizes and builds expansively from the suspension residue Caking on. These hard and firmly adhering coverings grow as the operating time continues to increase and come to the Exterior walls of the Honeycombs, which are thereby exposed to strong deformation forces. Below are the bearing surfaces the honeycomb on the carriers successively minimized, as a result, the honeycomb in the wash tower fall. These partially broken honeycombs affect the management and Availability the absorber particularly sustainable, z. B. by numerous blockages on screens and in piping of the washing circuit. This can until necessary decommissioning the absorber and upstream power plant processes lead.

The invention is based on the object, the penetration of leading to the clogging of the vertical column particles and the formation of Suspension residues between the honeycomb, their evaporation and the associated forces on the outer walls of the honeycomb and prevent their subsequent deformation.

These The object becomes in connection with the preamble of the patent claim 1 according to the invention thereby solved, that on straps resting honeycomb of the lowest layer of the wet film contact structure at their on the straps Overlying edges are provided with drainage recess and that the Honeycomb of the uppermost layer arranged at two at right angles to each other Pages at the upper edges, on the one hand, with vertical gaps between them Honeycomb covering Cover lips and on the other with the cover lips receiving Recess on the opposite sides of the cover lips of the honeycomb are provided.

The lowest layer of the wet film contact forming honeycomb of plastic, which are arranged side by side and the entire cross section fill in the absorber, lies on two sides with their lower edge on carriers. Due to the tight seal between the lower edge of this Honeycomb and the carrier can not penetrate into the vertical column absorber suspension run down and collects with the o. g. effects with progressive operating time in the vertical columns.

The Drain recesses now provide a simple and uncomplicated way and way, that an accumulation of the absorber suspension does not take place.

By the drain recesses can easily adjust the absorber suspension run down into the absorber. The honeycomb with such a drainage recess to be provided without any effort either before their first use or also possible afterwards.

simultaneously acts in this regard, the roofing the vertical gap between the honeycombs by means of the covering lips. The impinging often particle-loaded absorber suspension is simply to the side derived and flows unhindered by the cavities the honeycomb. Thus, a clearing of the vertical column of Absorber suspension and clogging particles effectively supported.

The Cover covering lips each the vertical column of the honeycomb, d. H. the honeycombs lie in several layers on top of each other, Only the top layer in the manner mentioned with the covering lips and provided with the recesses and at least the honeycombs of the lowest In this case, the drainage recesses are received on the supports resting on the supports Edge. If only one layer of honeycomb is provided, she receives the Cover lips on two sides arranged at right angles to each other at the upper edges, the recesses at the opposite of the cover lips Sides of the honeycombs and the drainage recesses on the supports resting on the edges.

The Cover lips and the receiving them recesses of each adjacent Honeycomb are to be dimensioned so that during operational movements the grid layers always ensure the coverage of the vertical column remains. For this it is advantageous that the cover lip the same Has width as the width of the recess. The covering lips and recesses should be arranged so that the surface of the top grid location a trouble-free Level forms.

A expedient embodiment the article of the invention provides, in more than one layer of honeycomb, which the wet film contact structure form each of the honeycombs with the drainage recess at the lower edge to provide. The honeycombs that do not rest on the carriers, so all those which do not form the lowest position, then have no direct Function for the flow of the suspension from the vertical columns, total However, this configuration has the advantage that in the production the honeycomb all honeycombs from the same original form (eg by deep drawing or by injection molding) can and not different prototypes are necessary, which is an enormous Cost savings brings with it.

The respective number of drain recesses on the resting on the carriers The edges of the honeycomb are to be chosen that on the one hand the stability of the Honeycomb is retained, on the other hand, but also the vertical gap can be sufficiently emptied of absorber suspension.

The stability can according to another embodiment thereby ensured be that in the opposite sidewalls a honeycomb drain recesses each offset are arranged. This allows the weight of the overlying layers of honeycomb be worn safely. The staggered arrangement of the drain recesses elevated additionally also the efficiency of the expiration of the absorber suspension from the vertical Gap.

Based an embodiment the invention will be described in more detail below to be discribed. Here the corresponding figure shows a detail a honeycomb arrangement of a three-layered wet film contact structure.

A flue gas desulfurization be stands, among other things, from an absorber in a cylindrical or rectangular tower-like construction. This is supplied via a flue gas duct in the lower area of the flue gas.

in the Absorber is z. B. after the wet scrubbing by means of a limestone suspension in countercurrent principle, the sulfur dioxide washed out. For this purpose, the flue gas flows from the lower part of the absorber through an absorption zone up and leaves the absorber over a clean gas line. The feeder the absorber suspension takes place via arranged in the upper part of the absorber nozzle systems, which in several Layers executed could be. About these nozzle systems The absorber suspension rests finely distributed over the cross section of the absorber downwards, falls down while the absorption zone and collects in the deeper area of the absorber. In the absorption zone, a wet film contact structure is used to increase the efficiency seconded. The wet film contact structure is increased by its special construction the contact surface. The thus wide-spread training wet film favors the absorption process. About that In addition, the flue gas flow rectified by the wet film contact structure.

The wet film contact structure consists of many rectangular honeycombs 1 made of plastic (eg polypropylene), which are arranged side by side as well as three layers above the other and fill the entire cross section of the absorber. The honeycomb 1 are formed by flat juxtaposed cavities, the cavities a z. B. have rectangular shape, are separated from each other by walls and enclosed by an outer circumferential side wall (Fig.). By way of illustration, the figure shows a section of the wet film contact structure, consisting of three layers of honeycomb, wherein the respective neighboring honeycomb is indicated on one side. The other all-round neighboring honeycombs are not shown. The representation of the three layers of honeycombs takes place in the form of an exploded view. When used in the absorber, the honeycombs of the upper layer lie on the honeycomb of the middle layer and these on the honeycomb of the lower layer.

Two side walls of each honeycomb 1 the lowest layer is burdened with carriers 5 on. In addition to a rectangular structure of the honeycomb 1 Here are also other structures already mentioned above possible.

Because the side walls of each adjacent honeycomb 1 between themselves vertical columns 3 train, become this column 3 pass through absorber suspension containing particles.

In the vertical columns 3 The bottom of the straps 5 are limited, accumulates the absorber suspension and the particles they contain, evaporates the liquid content and the remaining suspension residues form expanding caking, which blockages of the vertical column 3 cause.

So that it does not accumulate the absorber suspension in these vertical columns 3 comes, according to the invention, the honeycomb 1 the bottommost layer of the wet film contact structure at its on the supports 5 resting edges with drain recesses 2 Mistake. These ensure that the absorber suspension runs down freely. The drain recesses 2 have a height of approx. 25 mm and a width of approx. 50 mm and are present twice on each side wall. In order to continue to ensure the stability of the wet film contact structure, which are located in the opposite side walls drain recesses 2 staggered to each other. The staggered arrangement of the drain recesses 2 also ensures a good flow of the suspension over the entire length of the vertical columns 3 ,

Due to the double-sided arranged at right angles covering lips 4 and the precisely arranged recesses arranged opposite 6 a honeycomb 1 are when arranging all honeycombs 1 the top layer of the wet film contact structure all vertical column 3 covered. This can be done in the vertical column 3 no particle-laden absorber suspension penetrate and the vertical column 3 clog. The distance of the adjacent honeycomb from each other is about 5-10 mm. The covering lips 4 and the opposite arranged, the Abdecklippe 4 the neighboring honeycomb 1 receiving recess 6 are about 25 mm wide. This ensures a safe covering of the vertical gap even with thermal expansion of the entire wet film contact structure 3 , The thickness of the cover lips 4 and the depth of the recesses 6 is about 3 mm in size, so that a flat surface of a layer of honeycomb 1 given is.

Not shown in the figure is the expedient embodiment according to dependent claim 4 so that the possible recesses 2 in the middle and uppermost position of the honeycomb 1 not to be seen.

1

honeycomb

2

drain recess

3

vertical gap

4

cover lip

5

carrier

6

recess

Claims (5)

Washing tower, in particular for a flue gas desulphurisation plant, with a honeycomb contact film structure formed in one or more layers, characterized in that 5 ) resting honeycombs ( 1 ) the bottom layer of the wet film contact structure to its on the supports ( 5 ) resting edges with drain recesses ( 2 ) and that the honeycombs ( 1 ) of the uppermost layer at two sides arranged at right angles to one another at the upper edges on the one hand with vertical gaps ( 3 ) between the honeycombs ( 1 ) covering covering lips ( 4 ) and on the other hand with the covering lips ( 4 ) receiving recess ( 6 ) on the covering lips ( 4 ) opposite sides of the honeycomb ( 1 ) are provided. Washing tower according to claim 1, characterized in that the cover lip ( 4 ) has the same width as the width of the recess ( 6 ) and under all operating conditions the vertical gap ( 3 ) between the honeycombs ( 1 ) covers. Washing tower according to claim 1, characterized in that the thickness of the cover lip ( 4 ) equal to the depth of the recess ( 6 ), wherein the surface of the cover lip ( 4 ) with the upper edge of the honeycomb ( 1 ) is plan. Washing tower according to claim 1, characterized in that in the wet film contact structure, which consists of more than one layer honeycomb ( 1 ), each of the honeycombs ( 1 ) with the drainage recess ( 2 ) is provided. Washing tower according to one or more of claims 1 to 4, characterized in that the number of drain recesses ( 2 ) is to be chosen so that the stability of the honeycomb ( 1 ), the vertical gap ( 3 ) emptied sufficiently and each in the honeycomb ( 1 ) opposite drain recesses ( 2 ) are offset from one another.