EP2555858A1

EP2555858A1 - Spray system and method for spraying a secondary fluid into a primary fluid

Info

Publication number: EP2555858A1
Application number: EP11713276A
Authority: EP
Inventors: Stefan Hartig
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-04-09
Filing date: 2011-04-08
Publication date: 2013-02-13
Also published as: US20130068852A1; DE202011110485U1; CN102834168A; DE102010014580A1; WO2011124686A1

Abstract

The invention relates to a spray system for spraying a secondary fluid (5) into a primary fluid (1), wherein the secondary fluid (5) is gaseous or liquid or contains fine particulate solids which are to be dispersed in the primary fluid (1). The spray system comprises at least one central nozzle (6) for the primary fluid and at least one nozzle for spraying the secondary fluid(6), wherein a housing (3) of the nozzle has a tubular design and the central nozzle (6) is provided with a central passage for the primary fluid (1), wherein the passage, as seen looking in the flow direction, comprises a convergent inlet region (7), a constriction (8) and a divergent outlet part (9), wherein at least one outlet opening for the secondary fluid (5) is arranged on the downstream end (4) of the nozzle housing (3) and wherein at least one outlet opening is designed and arranged to generate a spray jet (12) of the secondary fluid (5) that surrounds the primary fluid (1) exiting the central passage in a substantially ring-shaped manner.

Description

description

Spray system and method of spraying a secondary fluid into a primary fluid

The invention relates to a spray system for spraying a secondary fluid into a primary fluid, wherein the secondary fluid is gaseous or liquid or contains fine particulate solids to be dispersed in the primary fluid, with at least one central nozzle for the primary fluid and at least one nozzle for Spraying the secondary fluid, wherein a nozzle housing of the nozzle is constructed tubular and the central nozzle has a central passageway for the primary fluid.

In many process plants, which are traversed by a primary fluid, the task is to mix a secondary, liquid or gaseous fluid or fine particulate solids as homogeneously as possible in the primary fluid. For this purpose, nozzles are used. Since the interference of the secondary fluid, to which we also want to count the particles suspended in fine particle form in a carrier fluid, is to take place within a very short running distance, a large number of nozzles is required, which cross the cross section of the - -

Primary fluid flowed through the process plant are distributed. This is associated with high costs, in particular for the spray lances required here, via which the secondary fluid is transported to the spray nozzles.

In many cases, the secondary fluid is introduced into the primary fluid with the aid of a sputtering aid. This sputtering assist medium may be, for example, compressed air or steam.

In the case of a so-called evaporative cooler for hot flue gases, water is usually sprayed as a secondary fluid in the form of fine droplets into the primary fluid, namely flue gas. As a rule, there is great interest in that the time required for the evaporation of the droplets is as short as possible, otherwise the dimensions of the process plant are very large, which is associated with high investment costs. However, it is not only about the droplet size distribution in the spray of the secondary fluid near the exit of the spray nozzles, but also about the intensity of the mixing of the primary gas to be cooled in the spray. The more intense this interference, the shorter the evaporation distance. In conventional nozzles, the mixing of the primary gas into the spray jet takes place over the conical surface of the spray jet. The primary gas flows through the edge zones of the spray jet toward the axis of the spray jet and, as a result of the flow resistance, also entrains drops toward the jet axis. Accordingly, there are unfavorable boundary conditions for the evaporation of the drops on the beam axis. Because the flue gas has already cooled down on the way to the axis of the spray and enriched with water vapor. Furthermore, very close to the beam axis usually high drop current densities, which is also very unfavorable for obvious reasons for rapid evaporation. - -

There is an analogous problem for dispersing solids in a primary gas flow. A high particle density is present on the axis of the spray jet of the introduced solid suspension, since the primary gas mixed in toward the axis of the spray jet entrains fine solid particles from the jet edge to the jet axis.

From the facts described in the introduction, the task for the present invention is derived. The spray system and the method should be such that the interference of the primary gas in the jet of secondary fluid is as intense as possible.

From German patent application DE 2634494 an injector is known to fumigate wastewater. A central propulsion jet nozzle for a liquid jet opens within a mixing chamber to which a gas is supplied. Downstream of the mixing chamber, a divergent outlet part is provided.

German Patent DE 2134100 C2 discloses a combustion chamber feed device in which a convergent / divergent Venturi nozzle is arranged within a cylindrical chamber. An air jet nozzle opens into the inlet of the Venturi nozzle. Fuel gas is to be sucked in via the Venturi nozzle and then fed to a combustion chamber downstream of the chamber.

From the German patent application DE 1957344 a spray nozzle is known with which a paste-like mass to be generated. An exit region of the nozzle is surrounded by an annular and compressed air-loaded annular gap.

From the US-Patent Publication US 2009/0031923 A1 a two-fluid nozzle is known, which has a plurality of outlet openings, which are arranged within an annular gap. - -

US Pat. No. 5,091,118 discloses a spray system for mixing oxygen into water. For this purpose, the liquid is passed through a convergent / divergent passageway. Within the passage channel, a central outlet opening for the gas is arranged.

The invention seeks to improve a spray system and method for injecting a secondary fluid into a primary fluid.

According to the invention, there is provided a spray system for injecting a secondary fluid into a primary fluid, the secondary fluid being gaseous or liquid or containing fine particulate solids to be dispersed in the primary fluid, having at least one central nozzle for the primary fluid and at least one nozzle for spraying the secondary fluid, wherein a nozzle housing of the nozzle constructed tubular and the central nozzle has a central passageway for the primary fluid, wherein the passageway seen in the flow direction has a convergent inlet area, a constriction and a divergent outlet part, wherein at least one outlet opening for the secondary fluid is disposed at the downstream end of the nozzle housing and wherein the at least one outlet port is formed and arranged to produce a spray of secondary fluid which is from the central one n passage channel exiting primary fluid substantially annular surrounds.

By means of the spray system according to the invention, the primary fluid is not mixed exclusively into the secondary fluid via an outer circumference of the spray jet. Rather, the primary fluid is additionally fed via the central nozzle to the central region of the spray jet. - -

In this way it is achieved that close to the axis of the jet of secondary fluid good evaporation conditions for drops exist or prevail favorable edge operations for the interference of the secondary fluid in the primary fluid. With such a configuration, it is possible to mix a substantially larger mass flow of the secondary fluid with a single nozzle into the primary fluid, because the sprayed secondary fluid not only from an outside of the spray but also from the inside of the spray toward the jet axis is mixed in the primary fluid. As a primary fluid, for example, flue gas to be cooled is used, into which a liquid, for example water, is to be sprayed for the purpose of evaporative cooling of the flue gas. As a sputtering aid, for example, compressed air or steam can be used.

In a further development of the invention, the at least one outlet opening is formed by means of a plurality of outlet openings for the secondary fluid, which are arranged annularly at the end of the nozzle housing.

By means of a plurality of annularly arranged outlet openings, a substantially annular spray of secondary fluid and atomizing aids can be produced.

In a further development of the invention, each of the plurality of outlet openings for the secondary fluid is surrounded by an annular gap for a gaseous atomization auxiliary medium.

In this way, many small individual nozzles, each formed as a two-fluid nozzle with an annular gap, arranged in a ring, so that they together produce an annular spray jet, which exerts a driving jet effect on the primary fluid. The provision of a plurality of annularly arranged individual nozzles, for example 12 individual nozzles, the - Are arranged in an annular manner, offers particular advantages if it is to be expected significant temperature differences. Such differences in temperature can occur, for example, between a condition with spraying off and spraying operation or between colder liquid to be atomized and hot gaseous atomizing aid. Small individual nozzles are less susceptible to disturbances due to thermal expansion in the region of the spray openings or spray gaps than a large annular nozzle. In both cases, the gap widths can be selected approximately the same size.

In a development of the invention, the at least one outlet opening is formed by means of a single annular gap arranged at the end of the nozzle housing.

In this way, a continuous, annular spray can be generated.

In a development of the invention, the annular gap for the secondary fluid is arranged within an annular gap for a gaseous atomization auxiliary medium.

In this way, a circulating spray of secondary fluid and atomizing auxiliary medium can be generated, which completely surrounds the primary fluid emerging from the passageway of the central nozzle.

In a further development of the invention, a swirl generator is arranged in the passage channel of the central nozzle.

By providing a swirl generator, the mixing of primary and secondary fluid can be further improved. - -

In a further development of the invention, at least one cleaning nozzle for keeping the inlet of deposits is provided at the upstream inlet of the passage channel of the central nozzle.

Due to the suction effect of the propulsion jet nozzle configuration in the spray system according to the invention is not assumed that the inlet of the central nozzle for the suction of the primary fluid is displaced by dust, since higher flow velocities are induced by the suction of Treibstrahldüsenkonfiguration at the inlet of the central nozzle. When loading the primary fluid, such as flue gas, with abrasive dusts is even more likely to erosion damage at the inlet of the central nozzle, so that an appropriate choice of materials must be made. In special cases, however, problems may arise with a formation of deposits in the inlet of the central nozzle. In this case, a small cleaning nozzle of the central nozzle can be preceded so that it keeps the inlet of dust deposits. Advantageously, this cleaning nozzle or even a plurality of cleaning nozzles can be connected to the supply line of the gaseous atomization aid.

In a development of the invention, the nozzle housing of the at least one nozzle is arranged in a channel carrying the primary fluid. Advantageously, the nozzle housing of the at least one nozzle spaced from a wall of the primary fluid-conducting channel is arranged.

In this way, the nozzle housing can be substantially completely flowed around by the primary fluid and at the same time, the primary fluid can pass through the passageway of the central nozzle. The essentially annular spray steel of secondary fluid and atomization aid emerging at the end of the nozzle housing can - Are surrounded by both on its inside and its outside of primary fluid.

In a further development of the invention, a channel leading parallel to the flow direction into the primary fluid is arranged with the longitudinal axis of the central nozzle.

In a further development of the invention, the at least one nozzle and the central nozzle in the form of a propulsion jet pump are designed such that the primary fluid at the entrance of the passage channel of the central nozzle is sucked by the propellant effect of emerging from the at least one outlet opening for the secondary fluid, substantially annular spray in that, downstream of the passage, the primary fluid is admixed both to a central region of the essentially annular spray emerging from the outlet and to an outer periphery of the substantially annular spray.

The problem underlying the invention is also solved by a method for injecting a secondary fluid into a primary fluid, wherein the secondary fluid is gaseous or liquid or contains fine particulate solids to be dispersed in the primary fluid, wherein generating a in the Substantially annular secondary jet fluid jet surrounding the downstream end of the passageway, priming the primary fluid at the upstream end of the passageway by a propulsion jet of the annular jet and mixing primary fluid with secondary fluid both in a region between a jet axis of the jet annular spray jet and the spray jet as well as in a region adjacent to an outer periphery of the spray jet area. - -

In this way, a very intensive mixing of the gaseous, primary fluid can be achieved in the spray of the secondary fluid.

Further features and advantages of the invention will become apparent from the claims and the following description of preferred embodiments of the invention in conjunction with the drawings. Individual features of the different embodiments shown can be combined with one another in any desired manner without going beyond the scope of the invention.

In the drawings show:

Fig. 1: a schematic sectional view of an inventive

Spray system according to a first embodiment,

Fig. 2 is a schematic sectional view of an inventive

Spray system according to a second embodiment,

Fig. 3: a schematic view of an inventive

Spray system according to a third embodiment against a flow direction and

Fig. 4: a schematic representation of an inventive

Spray system according to a fourth embodiment against a flow direction.

The illustration of Fig. 1 shows a basic configuration of a spray system according to the invention. In a primary gas 1 leading flue gas channel 2, an annular nozzle housing 3 is arranged with a nozzle main axis or with a longitudinal axis 16. From this nozzle housing 3, a secondary fluid 5 at the downstream end 4 enters into - - talt an annular spray 12 from. In this case, the total annular spray jet 12 may be formed by a plurality of individual jets, which are arranged on a ring, see. Fig. 3, Fig. 4 or as shown in Fig. 1, by a single annular gap beam.

The annular nozzle housing 3 encloses a central nozzle 6, which is formed by means of a passage channel with a convergent inlet region 7, a constriction 8 and a divergent outlet part 9, which follow one another in the flow direction. The secondary fluid 5 is supplied via the pipe 10 to an annular cavity 1 1 of the annular nozzle housing 3. The secondary fluid 5 fills this cavity 1 1 in operation of the nozzle and then exits at the end 4 of the nozzle housing 3 in the form of the annular spray jet 12. Due to the jet effect of the spray jet 12, which consists of the sprayed secondary fluid 5 and exiting the annular nozzle housing 3 at the end 4, primary fluid 1 is sucked in via the inlet region 7 of the central nozzle 6 and admixed downstream of the end 4 of the nozzle housing 3 to the spray jet 12 , The admixture takes place in a central region 13 of the spray jet 12, which extends from the central longitudinal axis 16 to the annular spray jet 12. Furthermore, primary fluid 1, which flows past the annular nozzle housing 3 on the outside, is mixed into the latter via the outer circumference, that is to say the lateral surface 14 of the spray jet 12. In this way, a very intensive mixing of the primary fluid 1, in particular flue gas, into the spray jet 12 of the secondary fluid 12, in particular water, can be achieved. Thus, according to the invention, an annular spray 12 of secondary fluid is created surrounding a core jet of primary gaseous fluid.

According to FIG. 1, the primary fluid 1 is not mixed into the secondary fluid 5 exclusively via the conical surface of the spray jet 12. Rather, the spray nozzle for the secondary fluid 5 is designed such - - That it acts as an annular propulsion jet nozzle on the primary fluid 1. Thus, the primary fluid 1 is additionally sucked via the central nozzle 6, which is similar to the inlet of a turbine air jet engine, and fed to the rich Zentralbe the spray jet 12. In this way, it is achieved that close to the axis 16 of the spray jet 12 good evaporation conditions for droplets exist or advantageous boundary conditions for the interference of the secondary fluid 5 in the primary fluid 1 are present. In such a configuration, it is possible to mix a much larger mass flow of the secondary fluid with a single nozzle in the primary fluid 1, because the sprayed secondary fluid 5 mixed not only from the conical surface but also from the jet axis 16 ago in the primary fluid 1 becomes.

2 shows a longitudinal section through an embodiment of the nozzle according to the invention. The nozzle for the secondary fluid is designed here as a two-fluid nozzle, in which a liquid is atomized as a secondary fluid with a gaseous Zerstäubungshilfsmedium and sprayed into the primary fluid, here in flue gas to be cooled, for the purpose of evaporative cooling of the primary fluid 1. The hot primary gas 1 is sucked axially by the Treibstahlpumpenwirkung the two-fluid nozzle and thus creates on the beam axis 16 from the beginning good boundary conditions for the evaporation of the drops. This two-fluid nozzle is further characterized in that the secondary fluid 5, the cooling fluid, exits via a narrow annular gap which runs coaxially to the main axis 16 of the spray nozzle. Furthermore, close to this annular gap for liquid radially inwardly and outwardly more annular gaps, over which the atomization auxiliary medium is blown. The annular gaps for the cooling liquid and for the atomization auxiliary medium are supplied via a supply line from outside with the appropriate fluids. - -

Instead of a single large annular gap nozzle, as shown in Fig. 2, which encloses a central nozzle for the suction of the primary fluid, of course, many small individual nozzles can be arranged in such a ring that they collectively exert an annular driving jet effect on the primary fluid 1 and this thus suction axially, see the embodiments of FIG. 3 and FIG. 4.

It is to be assumed that the inlet of the central nozzle 6 for the suction of the primary fluid 1 is not displaced by dust deposits, since higher suction velocities are induced by the suction effect of the jet jet nozzle configuration. When loading the primary gas 1 with abrasive dusts is in the inlet of the propulsion jet nozzle, the central nozzle 6, even more likely to erosion damage, so that an appropriate choice of material must be made. If, in special cases, problems with deposit formation in the inlet of the central nozzle 6 should occur, a small cleaning nozzle of the central nozzle 6 can be connected in such a way that it keeps the inlet of dust deposits. Such a cleaning nozzle 22 is also shown schematically in FIG. 2. This cleaning nozzle 22 could, for example, be connected to the supply line of the gaseous atomizing auxiliary medium.

A significant advantage of such an annular gap nozzle is that the distribution of the secondary fluid 5 and the sputtering auxiliary medium to the spray nozzle can be made much simpler than with a bundle head nozzle (cluster nozzle), which consists of a plurality of individual nozzles.

This applies in particular to emergency spraying, which only needs to be started in rare exceptional cases. These bundle nozzles can be supplied with fluids of very different temperature, for example water at 20 ° C. and steam at 300 ° C., which is used as decomposition gas. - - Dusting aid medium is used. The distribution of water and steam to the individual nozzles of the bundle nozzles is associated with a high cost and with the risk of considerable thermal stresses.

In the nozzle according to FIG. 2, the secondary fluid 5 is sprayed into the primary fluid 1 by means of an atomization auxiliary medium 15. The secondary fluid 5 exits from a concentric to the main axis 16 of the nozzle housing 3 annular gap 17 at the end 4 of the nozzle housing 3. The result is an annular spray jet 12 of secondary fluid. This annular spray jet 12 is affected on both sides by ring beams 15.1 and 15.2, which consist of sputtering auxiliary medium and which lead to a rapid disintegration of the spray jet 12 of secondary fluid. These ring beams 15.1 and 15.2 are generated by the sputtering auxiliary medium 15 emerging from the annular gaps 18.1 and 18.2 which are likewise concentric with the main axis 16. The effect of the spray jet 12 of secondary fluid 5 and the annular steel 15.1 and 15.2 of sputtering auxiliary medium 15 to the primary fluid 1 is substantially identical to the nozzle described with reference to FIG. Accordingly, here too primary fluid 1 is sucked in via the central nozzle 6 and mixed into the spray jet 12 of secondary fluid 5 from the nozzle axis 16. The supply of the secondary fluid 5 via at least one pipe 10. The supply of the sputtering aid 15 via at least one pipe 19. The secondary fluid 5 is fed through the nozzle housing 3, which has a symmetrical to the main axis of rotation hollow body 20, the annular gap 17. The atomization aid 15 is also supplied via the nozzle housing 3, which has a further symmetrical to the main axis 16 rotational hollow body 21, the annular gaps 18.1 and 18.2. - -

The nozzle housing 3 forms the toroidal rotational hollow body 21, which is supplied via the supply line 19 with atomization auxiliary medium 15. Within the rotary hollow body 21 of the further, also toroidal rotary hollow body 20 is arranged, which is smaller than the rotary hollow body 21 and which is supplied via the supply line 10 with the secondary fluid 5. The rotational hollow body 20 has an approximately semicircular upstream end viewed in the cross section of FIG. 2 and tapers as far as the annular gap 17 in the flow direction. The wall sections of the rotary hollow body 20 bounding the annular gap 17 are arranged at an angle to the main axis 16, so that Each of the outer walls of the annular gap 17 forms a truncated cone that widens in the direction of flow. The annular sections delimiting wall portions of the rotary hollow body 20 are not arranged parallel to each other but slightly tapering in the direction of flow. The rotary hollow body 20 thus forms a streamlined body-like shape in the cross-section of FIG. 2.

The rotary hollow body 20 is arranged in the larger rotary hollow body 21, which, viewed in the cross section of FIG. 2, also forms a streamlined body-like shape. At the upstream end of the rotary hollow body 21 is formed approximately circular section-shaped. This section forms with its inner side the inlet of the central nozzle 6. Subsequent to the inlet 7, the rotary hollow body 21 has walls arranged concentrically to the main axis 16, which thereby form the constriction 8 of the passage channel of the central nozzle 6. Subsequent to these walls arranged concentrically to the main axis 16, the rotary hollow body 21 tapers in the manner of a streamline body. The inner wall of the rotary hollow body 21, which faces the main axis 16, thereby forms the outlet part 9 of the passage channel of the central nozzle 6. - -

In the region of its downstream end of the rotary hollow body 21 forms the two annular gaps 18.1 and 18.2. For this purpose, the outer walls of the rotary hollow body 21 are guided in the region of the annular gap 17 of the rotary hollow body 20 substantially parallel to the outer walls of the rotary hollow body 20. Seen in the direction of the main axis 16, the annular gap 18.1 thus arises between the hollow rotary body 20 and the inner wall of the rotary hollow body 21. Seen from the main axis 16 outwardly between the outer wall of the rotary hollow body 20 and the outer wall of the rotary hollow body 21 of the annular gap 18.2 is formed. The annular gaps 18.1 and 18.2 are, as shown in FIG. 2 can be seen, approximately the same width. The annular gap 17 is also the same width as the annular gaps 18.1 and 18.2 in the illustrated embodiment. It is possible within the scope of the invention to make the gap widths different. The annular gaps 17 and 18.1 and 18.2 are arranged so that they each form a truncated cone widening in the direction of flow. The issued, annular spray jets 12 and 15.1 and 15.2 extend in the flow direction, therefore, also frusto-conical.

1 and 2 are schematic and it is specifically noted that in Fig. 1, the nozzle housing 3 is shown far too large compared to the diameter of the flue gas duct 2 and a container penetrated by flue gas, as a full-scale drawing is not meaningful would have been. In fact, the diameter D of the nozzle housing 3, as shown in Fig. 2, be on the order of 30 mm to 150 mm, while the diameter of the flue gas ducts 2 and container on the order of about 2000 mm to about 15,000 mm. The order of magnitude of the water flow to be atomized into small droplets with such a nozzle according to the invention is 100 l / min for an annular diameter of 100 mm, provided that the admission pressure of the atomizer - - Auxiliary air for spraying air at approx. 6 bar. The width of the annular gap 17 for the secondary fluid 5, see Fig. 2, and the width of the annular gaps 18.1 and 18.2 for the sputtering auxiliary medium 15 is of the order of 0, 1 mm to 1, 5 mm.

If steam is used as sputtering auxiliary medium 15, it may be advantageous to thermally isolate the water-carrying components, that is, the components which carry the secondary fluid 5, against the steam-carrying components.

The invention thus provides a spraying system comprising at least one nozzle for injecting a liquid or gaseous secondary fluid into a primary fluid or for dispersing fine particulate solids in said primary fluid, characterized in that the spraying system is in the form of a propulsion jet pump. which sucks primary fluid and supplies it to the central area of the spray jet. The spray system can be composed of many individual nozzles, which enclose a central nozzle in an annular manner, via which primary fluid is sucked. Alternatively, the spray system may consist of a single annular die via which the secondary fluid is sprayed with or without atomization aid and this annular die surrounds a central nozzle annularly via which primary fluid is drawn. In the central nozzle, a swirl generator can be arranged.

The invention thus relates to devices and methods for spraying fluids and for dispersing solids in channels or containers through which a primary gas flows. According to the invention, at least one nozzle is used for spraying a fluid or for dispersing fine particulate solids in said channels or containers. According to the invention, a multi-component nozzle with a primary gas jet is provided. Use finds the invention - - For example, in flue gas ducts or in flue gas cleaning plants in power plants or in the cement industry.

The illustration of Fig. 3 shows a spray system according to the invention according to a third embodiment of the invention. An annular nozzle housing 30 is toroidal in shape and has a shape similar to the nozzle housing 3 of FIG. 1. The nozzle housing 30 forms a rotational hollow body, to which secondary fluid is supplied via a feed line 32. The feed line 32 also serves to attach the nozzle housing 30 to the wall of a flue gas channel, cf. Fig. 2. The annular nozzle housing 30 encloses a passageway of a central nozzle 6 for primary fluid. The passageway of the central nozzle 6 has seen in the flow direction a convergent inlet, a constriction and a divergent outlet region and is similar to the passageway of the central nozzle 6 in Figs. 1 and 2 formed. The nozzle housing 30 is shown in the illustration of FIG. 3 counter to the flow direction. An outlet opening for the secondary fluid is formed by twelve circular outlet openings 34, which are annularly arranged surrounding the end of the passage channel of the central nozzle. By means of the outlet openings 34, a substantially annular spray of secondary fluid is generated as a whole, which, as explained with reference to the embodiments of FIGS. 1 and 2, exerts a propelling jet effect on the primary fluid within the passage channel of the central nozzle 6. The operation of the spray system shown schematically in Fig. 3 is characterized by the same as the operation of the spray systems according to the invention described with reference to FIGS. 1 and 2.

4 shows a further spray system according to the invention with an annular nozzle housing 40 which has a toroidal shape, as already described with reference to FIGS. 1 and 2 and the nozzle - - housing 3 has been described. The nozzle housing 40 is connected via a pipe 42 to an inner wall of a flue gas duct, see FIG. 1. In the tube 42 not shown supply lines for secondary fluid and gaseous sputtering auxiliary medium are arranged, for example, water or compressed air or steam. At a downstream end of the nozzle housing 40, as in the spray system of Fig. 3, a total of twelve outlet openings 34 for secondary fluid are arranged in a ring shape. Each of the secondary fluid outlet openings 34 is surrounded by an annular gap 44 for the gaseous atomization aid. The outlet openings 34 and the respective surrounding annular gaps 44 form a total of an annular spray of secondary fluid and Zerstäubungshilfsmedium. As in the above-described embodiments of FIGS. 1 to 3, this annular spray exerts a suction effect on the primary fluid at the inlet of the passage channel of the central nozzle 6. The operation of the spray system shown in Fig. 4 is therefore the same as already described with reference to the spray systems of FIGS. 1 to 3.

In a manner not shown, each of the secondary fluid outlet openings 34 may themselves be designed as an annular gap opening.

Claims

claims

A spray system for injecting a secondary fluid (5) into a primary fluid (1), the secondary fluid (5) being gaseous or liquid or containing fine particulate solids to be dispersed in the primary fluid, having at least one center nozzle (6 ) for the primary fluid (1) and at least one nozzle for spraying the secondary fluid (5), wherein a nozzle housing (3; 30; 40) of the nozzle is tubular and the central nozzle (6) has a central passageway for the primary fluid , characterized in that the passageway seen in the flow direction, a convergent inlet region (7), a constriction (8) and a divergent outlet part (9) that at least one outlet opening (17; 34) for the secondary fluid (5) at the downstream The nozzle housing (3; 30; 40) is arranged at the end (4) and that the at least one outlet opening (17; 34) is formed and arranged to form a sp Rührstrahl (12) of secondary fluid (5) to produce, which surrounds the emerging from the central passageway primary fluid (1) is substantially annular.

2. Spray system according to claim 1, characterized in that the at least one outlet opening by means of a plurality of outlet openings (34) is formed for the secondary fluid, which are arranged annularly at the end of the nozzle housing.

A spraying system according to claim 2, characterized in that each of the plurality of outlet openings (34) for the secondary fluid (5) is surrounded by an annular gap (44) for a gaseous atomization aid medium.

4. Spray system according to claim 1, characterized in that the at least one outlet opening by means of a single, arranged at the end of the nozzle housing annular gap (17) is formed.

5. Spray system according to claim 4, characterized in that the annular gap (17) for the secondary fluid (5) within an annular gap (18.1, 18.2) for a gaseous Zerstäubungshilfsmedium (15) is arranged.

6. Spray system according to one of the preceding claims, characterized in that the at least one outlet opening is formed and arranged to produce a starting from the end of the nozzle housing (3) conically widening annular spray jet (12).

7. Spray system according to at least one of the preceding claims, characterized in that in the passage channel of the central nozzle (6) a swirl generator is arranged.

8. Spray system according to one of the preceding claims, characterized in that at the upstream inlet (7) of the passage channel of the central nozzle (6) at least one cleaning nozzle (22) for keeping the inlet (7) of deposits is provided.

9. Spray system according to claim 8, characterized in that the at least one cleaning nozzle is connected to a supply line of a gaseous atomizing auxiliary medium (15).

10. Spray system according to one of the preceding claims, characterized in that the nozzle housing (3; 30; 40) of the less at least one nozzle in a primary fluid (1) leading channel (2) is arranged.

11. A spraying system according to claim 10, characterized in that the nozzle housing (3; 30; 40) is arranged at least one nozzle at a distance from a wall of the channel (2) carrying the primary fluid (1).

12. Spray system according to claim 10 or 1 1, characterized in that a central longitudinal axis (16) of the central nozzle (6) parallel to the flow direction in the primary fluid (1) leading channel (2) is arranged.

13. Spray system according to one of the preceding claims, characterized in that the at least one nozzle and the central nozzle (6) in the form of a propulsion jet pump are designed such that by the propelling jet of emerging from the at least one outlet opening for the secondary fluid, substantially annular Spray jet (12) the primary fluid at the entrance of the passageway of the central nozzle (6) is sucked, so that downstream of the passage channel, the primary fluid both a central region of the outlet from the exiting, substantially annular spray jet (12) and an outer periphery of the substantially annular spray (12) is mixed.

14. A method of injecting a secondary fluid into a primary fluid, wherein the secondary fluid is gaseous or liquid or contains fine particulate solids to be dispersed in the primary fluid, with a spray system according to any one of the preceding claims, characterized by producing a substantially annular and the downstream Secondary fluid spray jet (12) surrounding the passageway, priming the primary fluid at the upstream end of the passageway by a propulsion jet of the annular spray (12) and mixing secondary fluid secondary fluid both in a region between a jet axis (16) of the annular spray jet (12) and the spray jet (12) as well as in an area adjacent to an outer periphery of the spray jet (12).