WO2004105920A1

WO2004105920A1 - Method, system and device for gasflow cleaning

Info

Publication number: WO2004105920A1
Application number: PCT/DE2004/001067
Authority: WO
Inventors: Axel Kretzschmar
Original assignee: Axel Kretzschmar
Priority date: 2003-05-21
Filing date: 2004-05-19
Publication date: 2004-12-09
Also published as: EP1763394A1; DE10323355A1

Abstract

The invention relates to a method, system and device for a gasflow cleaning. The inventive method consists in leading a gas through flat spray fields (10) formed after each other perpendicularly to a gas flow direction. Said method does not require complicated plant equipment and can be used in a low-cost decentralised manner at any point of a channel of the gas flow. Said flat spray-type fields (10) are used in the form of barriers for gas. Finely sprayed liquid droplets bind, dissolve or adsorb pollutants contained in the gas. In order to produce a flat spray field, the inventive device comprises nozzles (2 to 5) arranged side by side in a tubular channel section perpendicularly to the gasflow.

Description

Method, arrangement and device for cleaning flowing gases

State of the art

The invention relates to a method, an arrangement and a device for cleaning flowing gases according to the preamble of the main claim.

In addition to process and environmental technology, the cleaning of gases also plays an important role in domestic technology in order to supply ventilated or air-conditioned rooms with breathable, clean, ie not only oxygen-rich, but also pollutant-free air. In those cases where only fresh air is drawn in from the outside atmosphere and brought into the rooms via ducts, no special cleaning technology is required except for the installation of filters. The filters retain dust and pollutant particles that may be found in the outside air. On the other hand, cleaning systems that generate fresh air from the extracted air and the rooms are more complex feed again. Here the cleaning and oxygenation takes place in central cleaning and

Treatment plants. The processes known per se from industry, such as air washing, filtration and separation, are used in the cleaning process. The cleaned air from the cleaning system returns to the rooms via ducts. These systems are either always in operation or have detectors that examine the extracted air for pollutants and put the system into operation when a limit value is reached. The installation of central cleaning and processing plants offers various advantages. In the process stages, which are usually connected in series, cleaning processes for pollutants of different types can be carried out in one system. Since such systems are relatively large, they are housed in separate rooms in which they do not affect the day-to-day operation in the business premises or rooms with public traffic. The system is connected to these rooms via ducts, which are usually installed in the ceiling or wall area without significantly affecting the room design. In facilities that are subject to absolute control, for example rooms without a direct natural one

Ventilation options, such as concert and theater halls, underground rooms, security facilities, etc., are of such vital importance. If the central cleaning and processing systems fail, the entire operation of such facilities is virtually shut down. In addition, there is now a not inconsiderable risk of deliberate contamination of air intended for ventilation with toxic substances with the aim of damaging or killing the people staying in these rooms. In such exceptional cases are central Cleaning and processing plants are ineffective, since the location and type of contamination are always undetermined. Even installed pollutant detectors can only alarm, but not decontaminate the air. It is technically possible to install cleaning and processing systems at different locations, especially in the vicinity of the rooms to be ventilated, but it is very complex and therefore uneconomical and would significantly impair the operation in the rooms. In addition, due to their high level of technical equipment, these systems are themselves very endangered and can therefore easily be rendered inoperable.

The invention and its advantages

The method according to the invention with the characterizing features of the first claim has the advantage over the prior art that it does not require any complex system technology and can also be carried out at any location of a channel through which the gas flows, without great installation effort. The gas is decentrally cleaned independently of complex cleaning and treatment systems and can therefore be carried out immediately before the air enters the room. The flat spray fields act as barriers to the gas. The finely sprayed liquid droplets bind, dissolve or adsorb the pollutants contained in the gas. The required contact time of the atomized liquid with the pollutant and the subsequent separation of the now contaminated liquid from the gas can be varied by the choice of the droplet size. The spray fields are most effective if they have almost the same droplet density over their entire area and the size the liquid droplets are approximately the same at all points in the spray field. It is cheapest to use water as the spray liquid. For special pollutants, especially when contaminated with toxins, it is necessary to add additives to the water. This means that pollutants can be removed selectively, but also entire groups of pollutants can be removed effectively. In the simplest case, a pipe system is required in which outlet openings for the spray liquid are provided at certain intervals.

According to an advantageous embodiment of the invention, pollutant detectors for solid particles, for example smoke, and also for harmful gases are arranged along the channels. When a certain concentration of the pollutants or pollutant gases is reached, they trigger a signal which also activates the spray system which generates the flat spray fields.

The arrangement according to the invention for cleaning flowing gases according to claim six provides to arrange the outlet devices for the spray liquid directly in the air supply and / or exhaust air channels of the rooms into which they lead. This decentralized arrangement of the outlet devices has the essential advantage that the gas can be cleaned virtually at any point in the channels. Similar to the detectors, the outlet devices are arranged one behind the other at certain intervals in the channels. This is possible without great effort, since in the simplest case outlet devices for the spray liquid can only be pipes provided with openings. In the case of smaller channels, a nozzle may already be sufficient to produce a flat spray field which fills the cross section of the channel, in which case at least two arranged one behind the other Spray fields are appropriate. In order to be able to fill its entire cross section with spray liquid in the case of larger channel widths, a further advantageous embodiment of the invention consists in arranging a plurality of outlet devices next to one another transversely to the direction of flow of the gas.

In the device for cleaning flowing gases according to the invention with the characterizing features of claim 8, the outlet devices for the spray liquid consist of nozzles arranged transversely to the direction of flow of the gas and producing a flat spray field. This nozzle arrangement has the advantage that the entire effective spray field, regardless of whether it is located in a horizontal or vertical plane, has the homogeneity with regard to concentration and uniform distribution of the water mist droplets necessary for effective binding of pollutants. This means that there is always the same amount of water droplets of approximately the same size per unit area of the spray field level. It is therefore now sufficient to install the piping system only in selected areas of the ducts or rooms, as a result of which the expenditure on materials and installation is significantly reduced. The use of nozzles with lower throughput also saves spray liquid. The installation effort on site is also reduced by the fact that the arrangement of the nozzles can be prefabricated in nebulization modules, which then only have to be strung together on site to form the pipe system corresponding to the requirements of the channels or the rooms. Connection systems known per se can be used to connect the individual nebulization modules. The technical implementation of the device according to the invention, ie the dimensioning and the determination of the radial and axial deflection of the nozzles, is carried out in accordance with the requirements of the flow channel or space in which the planar spray field is to be generated. The principle of the device is to arrange several nozzles next to one another in a nebulization module, which, however, due to their different spray angle and their different radial and axial deflection, do not spray in a line-like manner, but spatially and thus from the nebulization module to the desired spray field at different distances. The axial deflection causes a slight displacement of the spray surfaces, quasi a toothing of the spray surfaces applied to a gap.

The individual spray cones begin to touch one another at a certain distance from their outlet openings. The spray angle, throughput and radial and axial deflection are chosen so that this contact lies in one plane, the so-called spray field plane. At this level the above-mentioned favorable conditions prevail with regard to the homogeneity of the spray droplets necessary for an effective binding of pollutants. The different sizes of the spray angles of nozzles arranged next to one another is necessary so that the spray cones do not interfere with one another before this level is reached. The different lengths of travel due to the different radial and axial deflection of the nozzles from the spray droplets to this level are compensated for by correspondingly different spray angles. The smallest spray angle must be those nozzles that supply the spray field in the areas furthest away from the pipe system. When generating a uniform horizontal spray field, all the nozzles spray with the same intensity, ie the same quantities are sprayed on per unit area sprayed in a time unit and thus almost the same droplet size and droplet density prevail at all points of the spray field.

For the generation of vertical spray fields, gravity must be taken into account as a further disturbance variable. In addition to the different radial and axial deflection of the nozzles and their alternating large and small discharge angles, the throughput is also an additional component. The nozzles supplying the upper area of the vertical spray field must have a far greater throughput than the nozzles supplying the lower areas of the spray field. The latter only have to supplement the small drop spectrum, which has been lost due to the accumulation of droplets that have collided on the way down.

If larger areas have to be provided with spray mist, for example when decontaminating people in escape routes, several nebulization modules with one and the same nozzle arrangement must be arranged next to one another or also one above the other. Their distance should then be selected so that the outer spray cones in the spray plane at least touch each other. In this case, the spray surfaces which are slightly offset from one another in the spray plane of the one atomization module seamlessly join to the spray surfaces of the adjacent atomization module which arise in the same way, offset. According to an advantageous embodiment of the invention, the angle difference of the radial deflection of adjacent nozzles is 15 ° to 45 °. This range for the radial angular difference between adjacent nozzles has proven to be practical, whereby these angular differences from nozzle to nozzle can also be of different sizes.

According to a further advantageous embodiment of the invention, the angle difference of the axial deflection of adjacent nozzles between 5 ° and 20 ° has proven to be sufficiently suitable.

According to a further advantageous embodiment of the invention, hollow cone nozzles are used.

According to a further advantageous embodiment of the invention, a cylindrical filter is arranged in the nebulization module or modules. This prevents dirt particles from entering the nozzles and thereby blocking them. The cylindrical design of the filter also prevents the nebulizing module or the entire pipe system from becoming blocked, since it does not hinder their axial direction of passage.

Further advantages and advantageous embodiments of the invention can be found in the following description of the example, the drawing and the claims.

drawing

An embodiment of the device according to the invention is shown in the drawings and described in more detail below. Show here 1 is a nebulization module with four nozzles; and FIG. 2 is a schematic illustration of the flat spray field generated by the nebulization module shown in FIG. 1.

1 shows a water mist module 1 installed on the ceiling of a ventilation duct in a horizontal installation position for generating a vertical spray field. For orientation, a spatial coordinate system x y z is drawn on its right end face, which is intended to identify the position of the water mist module 1 in relation to the ventilation duct (not shown). With x the width of the traffic tunnel, to which the longitudinal axis of the water mist module 1 runs parallel, with y its extent in height and with z its length, i.e. the direction of flow of the air. The water mist module 1, with its outlet openings, has water mist nozzles 2 to 5 directed essentially opposite to the z direction, which are arranged on the water mist module 1 with the radial spray angles γ and axial spray angles ß mentioned in Table 1, the values for the spray angles γ and ß refer to a horizontal arrangement of the water mist module 1. The radial spray angle γ in the y-z plane and the axial spray angle ß in the x-z plane are each measured from the positive z-axis.

Table 1: Spray angles γ and ß of the water mist nozzles In addition to the special alignment of the water mist nozzles 2 to 5, the realization of a vertical, flat spray pattern also includes a special spray angle δ and an adapted volume flow. Both are listed in Table 2 for the present example. This table also lists the characteristics of a vertical planar spray pattern generated with these parameters, here actually only the values of an imaginary plane of the throwing parabola 1.5 m away from the water mist module 1 of the water mist emerging from the water mist nozzles 2 to 5 are given ,

This situation is also shown schematically in FIG. 2. The water mist nozzle 2 generates a water mist cone 6, the water mist nozzle 3 a water mist cone 7, the water mist nozzle 4, a water mist cone 8 and the water mist nozzle 5 a water mist cone 9. If the water mist module 1 is placed under water pressure, the cross-sectional areas of the water mist cones 6 to 9 form an approx. 1.5 m from their exit points from the water mist nozzles 2 to 5 level, measured in the negative z direction, a vertical, flat spray field 10, as can be seen from FIG. 2. The spray diameter of all water mist cones 6 to 9 is the same at this point and is approx. 0.87 m, which corresponds to a spray area of 0.59 m ² each. This is achieved by the different parameters of the water mist nozzles 2 to 5 mentioned in Table 2. The spray distance, i.e. the actual length of the spray cone from its exit point to this level, is shown in column 3 of table 2. So that there are no gaps in the spray field, slight overlaps of the water mist cones 6 to 9 have to be accepted. In order to generate a constant drop spectrum and a constant droplet density in the spray field 10, the volume flow of the water mist nozzles 2 to 5 becomes smaller with a falling spray angle δ. In this example, the volume flow is reduced by half. To create a vertical, level spray field with ventilation duct heights of 2.75 m, approx. 21 1 / min of water are required per water mist module 1 in order to achieve a range of 1.50 m with an effective width of 1.50 m.

For the generation of a horizontal spray field, the water module 1 is rotated downward by 90 ° about the x axis. The radial or axial position of the water mist nozzles 2 to 5 with respect to one another is retained, but the radial spray angle γ assumes a value greater by 90 ° due to the rotation in the abovementioned measurement rule. The water mist nozzles 2 to 5 used have the same spray angle δ as in the arrangement for the vertical planar spray field, only the volume flow is the same for all water mist nozzles 2 to 5 and is 5.25 1 / min in the present example. If the water mist module 1 thus arranged is placed under water pressure, a horizontal, flat spray field is created which also has spray surfaces of the same size per water mist nozzle 2 to 5 and a constant droplet spectrum and a constant droplet density. Of course, the water mist modules 1 can also be used in the vertical guidance of spray arches. However, they do not necessarily have to generate even spray fields in this area. Their main function here is to seal the area between the vertical water mist curtain and the side walls of the ventilation duct so that no pollutants can get through here.

All features shown in the description, the following claims and the drawing can be essential to the invention both individually and in any combination with one another.

LIST OF REFERENCE NUMBERS

1 water mist module

2 to 5 water mist nozzles 6 to 9 water mist cones 10 spray field ß axial spray angle (deflection of the water mist nozzle) γ radial spray angle (deflection of the water mist nozzle) δ spray angle

Claims

Method, arrangement and device for cleaning flowing gas claims

1. A method for cleaning flowing gases by gas scrubbing by means of liquids, characterized in that the gas is arranged transversely to it by successively arranged

Flat spray fields (10) generated are directed.

2. The method according to claim 1, characterized in that the flat spray fields (10) have an almost identical droplet density and droplet size over the entire surface.

3. The method according to claim 1 and 2, characterized in that water is used as the spray liquid.

4. The method according to claim 3, characterized in that additives are added to the water, which neutralizes the toxins contained in the gas.

5. The method according to claim 1 to 4, characterized in that the spray fields (10) are only triggered when an adjustable threshold value for the contamination or contamination of the gas is reached.

6. Arrangement for cleaning flowing gases which have outlet devices for liquids, characterized in that the outlet devices are arranged one behind the other in air supply and / or exhaust air channels of rooms.

7. Arrangement according to claim 6, characterized in that a plurality of outlet devices are arranged side by side in a line running transversely to the direction of flow.

8. Device for cleaning flowing gases, which have outlet devices for liquids, characterized in that the outlet devices are arranged on a pipe section next to one another transversely to the direction of flow of the gas and produce a flat spray field (10) nozzles (2, 3, 4, 5).

9. The device according to claim 8, characterized in

- The nozzles (2, 3, 4, 5) which produce the flat spray field (10) or parts of such a nozzle are arranged next to one another in at least one nebulizing module (1) forming a pipe section,

- The nozzles (2, 3, 4, 5) have different spray angles (δ),

- The axes of the nozzles (2, 3, 4, 5) have different deflections (γ) both radially to the pipeline and also different axial deflections (ß) from one another, so that the resulting spray cones are at least in the desired, ie. H. from the pipeline at a certain distance from the spray field level do not hinder each other or only insignificantly, whereby

- The nozzle (4) with the smallest spray angle (δ) the largest radial

Deflection (γ) and the nozzle (3) with the largest spray angle (δ) has the smallest radial deflection (γ),

- The nozzles (2, 3, 4, 5) arranged side by side alternately have a large and a small spray angle (δ) and

- -The axial deflection (ß) juxtaposed nozzles

(2, 3, 4, 5) is selected so that its associated spray surfaces (6, 7, 8, 9) arise vertically or horizontally offset from one another in the spray field plane (10).

10. The device according to claim 9, characterized in that a plurality of nebulization modules (1) are arranged one behind the other in air supply and or exhaust air channels of rooms.

11. The device according to claim 9, characterized in that adjacent nozzles (2, 3, 4, 5) for generating a horizontal flat spray field (10) have the same throughput.

12. The apparatus according to claim 9, characterized in that adjacent nozzles (2, 3, 4, 5) for generating a vertical, flat spray field (10) have a different throughput.

13. The apparatus according to claim 12, characterized in that the nozzle (4) with the smallest spray angle (δ) has the smallest and the nozzle (3) with the largest spray angle (δ) has the largest volume flow.

14. The device according to claim 9 to 13, characterized in that a plurality of nebulization modules (1) are arranged side by side.

15. The apparatus according to claim 9 to 14, characterized in that the angular difference of the radial deflection (γ) of adjacent nozzles (2, 3, 4, 5) is 15 ° to 45 °.

16. The apparatus according to claim 9 to 15, characterized in that the angular difference of the axial deflection (β) of adjacent nozzles (2, 3, 4, 5) is 5 ° to 20 °.

17. The apparatus according to claim 9 to 16, characterized in that hollow cone nozzles are used as nozzles (2, 3, 4, 5).

18. The apparatus according to claim 9 to 17, characterized in that there is a cylindrical filter in the nebulization module (1).

Two pages of drawing