EP2408546A1

EP2408546A1 - Operationally reliable coating device for powdery material

Info

Publication number: EP2408546A1
Application number: EP10709230A
Authority: EP
Inventors: Heinz Meier; Christian Buerge; Beat Schnider
Original assignee: Sika Technology AG
Current assignee: Sika Technology AG
Priority date: 2009-03-19
Filing date: 2010-03-19
Publication date: 2012-01-25
Also published as: US20120070565A1; EP2230005A1; MX2011009367A; WO2010106153A1; BRPI1009414A2; CN102355944A

Abstract

The invention relates to a device (1 ) for coating powdery material (2) with at least one liquid additive (3). Said device (1) comprises a conveying device (4) which contains a conveyor line (5) which transports the powdery material (2), in addition to an introduction device (6) for introducing the liquid additive (3) onto the conveyor line (5) comprising the powdery material (2), also comprising a cleaning device (7) for cleaning the introduction device (6). Said introduction device (6) comprises a supply line (8) and at least two nozzles (9), said liquid additive (3) can be introduced onto the conveyor line (5) and added to the powdery material (2) by means of at least one nozzle. The invention also relates to a method for coating powdery material (2) with at least one liquid additive (3) and to the use of a device (1) for coating powdery material (2) with at least one liquid additive (3).

Description

OPERATIONAL COATING DEVICE FOR

POWDERFUL MATERIAL

TECHNICAL FIELD The invention relates to a device for treating, in particular coating, pulverulent material with at least one liquid additive. The device comprises a conveying device, which contains at least one conveying line, through which the powdered material is conveyed, and at least one introduction device for introducing the liquid additive into the at least one conveying line according to the preamble of the first claim.

Furthermore, the invention relates to a method for treating pulverulent material with at least one liquid additive and to a use of a device for treating pulverulent material with at least one liquid additive according to the preambles of the further independent claims.

State of the art

The material cement is usually obtained from cement clinker. Here, the cement clinker, the precursor of the cement rotary kiln, ground to cement powder, then mixed with gypsum, which acts as a setting regulator, resulting in the mixing process, the final product cement. The recovered cement is stored in silos after production. For further processing into concrete, the material cement is mixed with aggregates, chemical additives and water. The addition of the additives should improve the properties of the concrete in chemical and / or physical terms. For example, the additives can influence the flow properties, the viscosity, the compression behavior and the setting behavior of the concrete. The addition of liquid additive during the

Further processing, in particular the promotion, is difficult, since the required for the production of the concrete powdery materials, in particular their dust, can react with the liquid additive and by Contamination of the introduction device affect the introduction of the liquid additive. In particular, in the pneumatic conveying of the powdery materials required for the production of the concrete typically prevail high dust concentrations and / or high temperatures, which is the formation of the mentioned contamination particularly beneficial.

Further, by the liquid admixture itself, for example by precipitation thereof or by impurities contained therein, contamination of the introduction device and obstruction of the introduction of the liquid admixture may occur. A reliable and controllable introduction of the liquid additives is important for a consistent quality of the final product.

DESCRIPTION OF THE INVENTION The object of the present invention is therefore to ensure a controlled, reliable and constant treatment of the powdery material with liquid additive in a device of the type mentioned in the introduction.

According to the invention, this is due to the features of the first

Claim achieved.

It is therefore the essence of the invention that the device 1 has at least one cleaning device 7 for cleaning the introduction device 6, and that the introduction device 6 comprises a supply line 8 and at least two nozzles 9, wherein in each case at least one nozzle 9, the liquid additive 3 in the Delivery line 5 and the powdery material 2 can be inserted.

Among other things, the advantages of the invention can be seen in the fact that the often arising inner 21 and outer 31 contaminants can be eliminated by the cleaning device 7 and / or them is prevented and thus a constant treatment of the powdery material 2 can be ensured with liquid additive 3.

Characterized in that the device comprises at least two nozzles 9, the reduction of the delivery rate of the liquid additive 2 can be compensated by contamination and / or cleaning a nozzle by another nozzle and thereby reliable treatment of the powdery material 2 with liquid additive 3 can be ensured ,

The device should therefore prevent and / or eliminate and / or compensate for a decrease in the delivery rate of the liquid admixture 2 due to contamination of the delivery device.

It is particularly expedient if the cleaning device 7 permanently cleans the introduction device 6 at regular intervals or at regular intervals, whereby the formation of soiling can be prevented. Further expedient for the prevention of contamination is that the device further protective devices 13 for the nozzles 9 in the conveying line 5 has.

It is also advantageous that at least one of the nozzles 9 is arranged to be movable into and out of the delivery line 5. This is, inter alia, the prevention of external contaminants 31 conducive, since thereby nozzles, in particular the outlet opening 16, are protected from the dust 20 of powdery material 2. Furthermore, nozzles outside the delivery line can thereby be cleaned by a cleaning device 7, which improves the cleaning environment. Next can thereby

Need, for example, to maintain or change the delivery rate of the liquid additive 2, additional nozzles are fed into the delivery line 5 or nozzles are removed therefrom while unused

Nozzles outside the delivery line are protected from dust.

It is further advantageous that at least two nozzles 9 of the introduction device 6 are arranged on a movable mold part 15. If a nozzle 9 is clogged and / or cleaned, the movable mold part 15 can be indexed by one position to the next nozzle. As a result, the dead time without promotion can be greatly reduced and the promotion of the liquid additive 3 remains guaranteed because there is the possibility of resorting to further nozzles of the movable molding.

Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of the dependent claims.

Brief description of the drawings

In the following, embodiments of the invention will be explained in more detail with reference to the drawings. The same elements are provided in the various figures with the same reference numerals. The flow direction of the media is indicated by arrows.

Show it:

Fig. 1 is a schematic representation of a

Embodiment;

Fig. 2 a - b lateral views of possible movable moldings; 3 a - c are views of possible nozzles with protective device; 4 a - b are views of a possible nozzle with cleaning device and protective device;

Fig. 5 view of a possible nozzle with a possible

Cleaning device;

Fig. 6 is a further schematic representation of a

Embodiment.

Only the elements essential for the immediate understanding of the invention are shown. Ways to carry out the invention

In Fig. 1, the schematic structure of a device 1 for treating, in particular coating, of powdered material 2 with at least one liquid additive 3 is shown. The apparatus 1 comprises a conveying device 4 which contains at least one conveying line 5 through which the powdery material 2 is conveyed, and at least one introduction device 6 for introducing the liquid additive 3 into the at least one conveying line comprising the powdery material 2 at least one cleaning device 7 for cleaning the introduction device 6. The introduction device 6 comprises a supply line 8 and at least two nozzles 9, wherein in each case at least one nozzle 9, the liquid additive 3 in the delivery line 5 and the pul verförmigen material 2 can be inserted. By "powdered material" is meant in this document a material which is obtained by breaking up a dry solid, for example by crushing, grinding, crushing or milling in mills, or by spray-drying.

According to the grain size, a rough classification of the powdery materials is possible; a more accurate classification of powdered materials is carried out, for example, by their bulk density and sieve analysis. Advantageously, the powdery materials, especially in pneumatic transport, a flow behavior that is reminiscent of liquids. The pulverulent materials 2 typically have a particle size of essentially 1 to 200 μm, preferably 3 to 30 μm and / or a Blaine fineness of 2000 to 8000 cm ² / g, preferably 3000 to 6000 cm ² / g.

As a powdery material 2 are non-hydraulic, hydraulic and latent hydraulic powder material of all kinds, preferably such, which is needed for the construction industry in large quantities.

In addition, all materials which are used for the production of concrete, mortar or gypsum, in particular cement particles, are suitable in principle as powdery materials 2. It can also substances or additives, such as For example, silica, fly ash, light aggregate, slag, fiber materials, for example, organic such as polypropylene fibers, etc. or inorganic such as basalt, glass, etc. may be used.

It should be emphasized that it is possible in principle to treat all substances used for the production of concrete, mortar or gypsum with liquid additive 3, in particular to coat. The treatment of the powdery material may advantageously be carried out where the pulverulent materials are conveyed pneumatically. This means that the treatment process does not necessarily have to take place during the production of the concrete, mortar or gypsum. The raw materials can therefore already be treated at the place of their production. For example, the cement particles can be treated directly at the end of the cement production process.

The powdery material 2 preferably comprises at least one binder which is preferably selected from the group consisting of cement, mortar, gypsum, silica, fly ash, slag and blast furnace slag or a mixture thereof. Particularly preferably, the powdery material 2 is cement.

As liquid admixture 3 are typically suitable substances which are atomized (aerosol) and / or droplets (drops) and / or vaporized (steam) can be and have a viscosity of 1-500 mPa * s.

For example, here are not some final liquid additives, from whose name usually the effect is listed: Concrete plasticizers, flow agents, air entrainers, (reaction) retarders, accelerators, such as solidification and hardening accelerators, stabilizers, chromate reducers, Einpresshilfen, foaming agents, air entraining agents, sealants , Corrosion inhibitor and recycling aids.

The at least one liquid additive 3 is typically selected from the group consisting of dispersant, condenser, flow agent, retarder, accelerator, stabilizer, shrinkage reducer, air entraining agent and corrosion inhibitor or a mixture thereof. It is particularly advantageous as a liquid additive a

High performance concrete liquefier, preferably the product ViscoCrete®

Company Sika, to use. This high-performance concrete condenser reduces the water content of cement and improves the workability of the concrete.

The conveying device 4, which contains at least one conveying line 5, through which the powdery material 2 is conveyed, is typically a conveying device in the construction industry. Such a conveyor device 4 is used, for example, for transporting the production of the powdery material 2 to an intermediate storage, such as an intermediate silo, to a mobile means of transport, such as a truck or railway wagon, or a repository. The conveying of the pulverulent material 2 in a conveying line 5 is generally carried out by means of bucket elevators, conveyor belts, pneumatic or in so-called air conveyor troughs, also called "air slides." Such air troughs are commercially available, for example, from Mahr GmbH, Germany typically of rectangular steel tubes having a width of 10-100 cm and a height of 10-100 cm, the powdery material 2 has, during conveyance, therein a filling level of typically% by% of the area provided for the powdered material Material 2 in an air conveyor trough is based on the fluidization of the powdered material by air, as well as the inclination of the trough of 5 to 10 °, which together with the kinetic energy which brings the powdery material in entering the air conveyor trough, allows movement of the powdery material t.

The fluidization is done by flowing with air from below through the located on a perforated substrate powdery material, whereby the particles of the powdery material remain within the resulting fluidized bed in a continuous up and down movement and so to speak remain in limbo. The separation of Fluidisierluft and the powdery material is carried out by a release fabric made of plastic or glass fibers, wherein the fluidizing air can pass through the tissue, the powdered material 2 to be delivered but not. In the delivery line 5 often prevail temperatures of up to 120 ⁰ C, further forms above the powdery material 2 dust 20 of powdery material.

The term "dust" in the present document is understood to mean the unwanted disperse distributions of solids, in particular of pulverulent material 2, in gases produced by mechanical processes or by fluidization, in particular by transport in the conveying line 5, the solid substance being in the ambient air is dispersed within the conveying line 5

Preferably, the delivery line 5 is an air conveyor trough. Typically, the powdery material 2 becomes a constant

Speed of about 0.5 - 10 m / s transported by the conveyor line 5.

The introduction device 6 for introducing the liquid admixture 3 into the at least one delivery line 5 comprises a supply line 8 and at least two nozzles 9. Via at least one nozzle, the liquid admixture 3 can be introduced into the delivery line 5 and to the powdery material 2.

The liquid additive may, for example, be atomized and / or dropped and / or vaporized. Due to the different consistency, the coating thickness of the powdery material can be adjusted with the liquid additive.

The liquid additive 3 is typically conducted to the at least two nozzles 9 via the supply line 8 at a pressure of 1-15 bar, preferably 3-7 bar. Typically, the pressure of the supply line is greater than or equal to, in particular greater than the nominal pressure of the nozzles. Advantageously, the introduction device 6 to a pump 10 for conveying the liquid additive 3, and at least one valve 27 in front of at least one nozzle 9. Typically, the supply line 8 consists of a main supply line 81 and Sub-lines 82, which connect the main feed line 81 with the nozzles 9.

Suitable nozzles 9 allow, inter alia, the spraying of liquid additive 3 at pressures of 1 to 30 bar, preferably 3 to 7 bar. Typically, these are flat jet nozzles, mist nozzles or two-component nozzles, in particular flat-jet nozzles.

Fog nozzles are advantageous in that they can atomize pressurized liquids into very fine droplets with a large specific surface area.

Two-substance nozzles are characterized by a very fine atomization by the mixing of liquids with air or gas. Further, they can produce various spray patterns, such as flat jet, hollow cone or full cone spray patterns. Flat jet nozzles are characterized by a uniform liquid and pressure distribution. Furthermore, they allow a great variability in the choice of the spray angle. Particularly suitable nozzles have a spray angle of 30 ° - 120 °. Depending on the design of the outlet opening 16 of the nozzle, an elliptical or rectangular impact surface is possible. Flat jet nozzles are inexpensive and allow by a defined and easily adjustable impact surface the targeted treatment of the powdery material 2 with the liquid additive 3. This is to the effect of advantage that thereby the contact of the liquid additive 3 with the delivery line 5, in particular the walls and, if it is an air conveyor trough, the separating fabric, can be avoided. This reduces the risk of blocking the delivery of the powdery material 2 in that either the fluidization of the powdery material 2 is restricted or the powdery material settles on the walls and clumps. Typically, the at least two nozzles have one

Nozzle bore 161 of 0.1 - 1 mm. The nozzles 9 are typically arranged on the conveying line 5 in such a way that the liquid additive 3 can be brought into contact as evenly as possible with the largest possible part of the powdery material 2. Typically, the nozzles are arranged on the powder material 2 opposite wall of the delivery line. It is also advantageous if the nozzles, in particular the outlet opening 16, in the conveying line 5 have the largest possible distance to the powdery material 2. On the one hand, this allows a greater flexibility in the treatment with the liquid additive 3, on the other hand, the nozzles are less exposed to the dust 20 of the powdery material 2, whereby the possibility of external contamination 31 of the nozzles is reduced.

The distance between the outlet opening 16 of the nozzle 9 and the powdery material 2 is typically dependent on the filling level of the powdery material 2, the shape of the cross section of the conveying line and the spraying angle of the nozzle.

It is also advantageous if at least one of the nozzles 9 is arranged to be movable into and out of the delivery line 5. As a result, nozzles, in particular the outlet opening 16, can be protected from the dust 20 of the powdery material 2. Furthermore, nozzles outside of the delivery line 5 can be cleaned by a cleaning device 7, which improves the cleaning environment. Further, if required, for example, to maintain or change the delivery rate of the liquid additive 3, additional nozzles may be introduced into the delivery line 5 or nozzles removed therefrom. Unused nozzles can be protected so outside of the delivery line from the dust 20 of powdery material 2.

Preferably, the movement of the at least one nozzle into the delivery line 5 in or out is regulated by a control system 11. It may also be advantageous that the introduction device 6 comprises at least three nozzles. It is also advantageous if at least two nozzles 9 of the introduction device 6 are arranged on a movable mold part 15, wherein the movable mold part 15 is preferably round, oval or angular.

The movable mold part 15 is typically a flat profile or a disk on which a plurality of nozzles 9 are mounted, as shown in Figures 2a and 2b. The movable mold part 15 is typically at the delivery line

5 arranged that nozzles, which promote no liquid additive 3, are protected from the dust 20 of powdery material. This can for example be achieved in that the movable mold part is attached to the outside of the delivery line and those nozzles, which liquid

Promote additive 3, via an opening 19 in the delivery line in the

Delivery line to be moved and liquid additive 3 spray on the powdery material 2, while the nozzles, which promote no liquid additive, outside of the conveying line 5 are. It is also possible that the movable molding on the inside of the

Delivery line is attached and a protective device 13, typically a cover, those nozzles, which promote no liquid additive protects.

If a nozzle 9 is clogged by soiling and / or cleaned, the movable molding 15 can be indexed by one position to the next nozzle. This allows the dead time without

Promotion of the liquid additive 3 are greatly reduced. Preferably, the indexing by a control system 11 is adjustable.

By means of suitable seals it can be ensured that during the change from one to the next nozzle no liquid additive 3 emerge from the nozzles and no dust 20 of powdered material comes into contact with nozzles which are not in use.

Another advantage of the movable mold part 15 is that in the case of a blockage of a nozzle, the promotion of the liquid additive 3 is ensured, since there is the possibility of recourse to other nozzles of the movable molding.

However, the nozzles 9 can also be worked directly into the movable molding 15. This construction method would bring significant cost savings bring and would have advantages in sealing the nozzles to prevent the escape of liquid additive 3 from the nozzles during the change from one to the next nozzle.

It may also be advantageous if the device 1 has several, in particular three or more, movable mold parts 15.

Preferably, the feed line 8 before each movable mold part a valve 27 and / or a means 25 for determining the flow rate FI üse _D of the liquid additive 3 from the conveying nozzle of the movable mold 15. Through the valve 27 a movable mold part 15 can be activated or deactivated and the means 25 for determining the flow rate FI _D üse allows for example the detection of a contamination of the conveying nozzle, after, for example, an indexing and / or cleaning the soiled nozzle, for example, if necessary can be initiated.

At least one of the nozzles 9 of the device 1 mentioned above may have a protective device 13, wherein the protective device 13 is arranged in the conveying line 5. This protective device serves, in particular, to protect the nozzle, in particular the outlet opening 16, from the powder 20 of powdery material 2. The protection device 13 is typically a cover or air curtain 14, in particular an air curtain.

It is also advantageous if the protective device 13 can be regulated by a control system 11. A cover shields a nozzle, in particular the outlet opening

16, typically substantially entirely from the dust 20, and is particularly used for nozzles that are not in use. This solution is simple, effective and cost effective.

An air curtain 14 may partially surround or completely surround a nozzle 9, in particular the outlet opening 16, as shown for example in FIG. 4b. Further, the air curtain 14 may be substantially parallel, such as in Figure 3c, concentric, such as in Figure 3a, conical, such as in Figure 3b, or orthogonal, as for example in Figure 4b, be arranged to the axis of the discharge direction of the liquid additive 3 from the nozzle.

Figure 4a shows, inter alia, the inner part of a nozzle 9 with the

Nozzle bore 161 and the inner part of the outlet opening 16. To the nozzle bore 161 are bores of the blower 141 of the

Air curtain 14 and holes for the compressed air supply line 22 arranged to clean the nozzle. In Figure 4b, the outlet opening 16 is visible. By the

Blower 141 becomes substantially orthogonal to the axis of

Exit direction of the liquid additive 3, an air curtain 14 is formed. FIG. 3a shows a blow-out device 141 which has an air curtain

14 forms with its axis substantially parallel to the axis of the discharge direction of the liquid additive 3.

FIG. 3b shows a blow-out device 141 which has an air curtain

14 is substantially conical to the axis of the exit direction of the liquid additive 3 forms. Such an orientation of the air curtain is advantageous in that the outlet opening 16 of the nozzle of all

Pages from the dust 20 is protected.

FIG. 3c shows a blow-out device 141, which forms an air curtain with its axis substantially parallel to the axis of the outlet direction of the liquid additive 3 and is arranged in the transport direction of the powdery material 2 in front of the nozzle.

An air curtain 14 exits the blower 141 at a pressure of typically 0.1-1 bar.

The device 1 has at least one cleaning device 7 for

Cleaning the insertion device 6. The cleaning device 7 may comprise a means 12 for cleaning the introduction device 6, which is selected from the group consisting of sieve, solvent, compressed air, mechanical tool and ultrasound, in particular compressed air. Further, the cleaning device 7 parts or the whole

Carrying device 6 as needed and / or time permanently or at regular intervals clean and it may be advantageous if the cleaning device 7 is regulated by a control system 11. The cleaning device 7 can be arranged further inside or outside the delivery line 5

Such means 12 can be used for cleaning the supply line 8 and / or the nozzles 9.

Typical contaminants are internal contaminants 21 and external contaminants 31. In the present document, internal contamination 21 means contaminants which are located in the supply line 8 or within the nozzle 9, typically in the nozzle bore 161. Internal contaminants 21 are mainly due to contamination in the liquid additive 3 or by unusual liquid additive. Such internal contaminants can clog the main supply line 81 and thus interfere with the inflow to all the nozzles that clog the secondary supply lines 82 or the nozzles 9 themselves inside. Under external pollution 31 are in the present document

Pollutions understood, which are at the outer part of the nozzle, in particular at the outlet opening 16, which comes into contact with the dust 20 of powdery material 2. Such external contaminants 31 are typically caused by dust deposits and in particular by accumulations, typically drops, of liquid additive at the nozzle, which cause the dust 20 within a short time to clumps that can clog the nozzle externally.

With the aid of a sieve or filter, typically made of metal or plastic, blockages could be prevented by internal contaminants 21. Of course, in the selection of the mesh size, the viscosity of the liquid additive 3 and the size of the outlet opening 16 of the nozzle must be taken into account.

Another means 12 for cleaning the introduction device 6 is compressed air 17, which is pumped through the introduction device 6. This can be done periodically, for example to prevent blockages, or in case of current blockages. Thus, for example, could be funded by the supply line 8 recurrently 10 seconds of liquid additive 3 and then for 1 second compressed air 17. Switching the necessary Valves 27 can be easily accomplished, for example, by means of a normally open and a closed valve. The compressed air typically leaves the supply line 8 through the nozzles 9. Further, compressed air can be passed through the entire supply line 8 or only through certain areas, such as the area in front of a nozzle 9. In the latter case could be clogged from the inside by an internal pollution 21 Nozzle are blown specifically with compressed air 17. The nozzle can be located inside or outside the delivery line 5. By blowing out the nozzle outside the feed line, the transport of the powdery material 2 would not be disturbed.

FIG. 2 b shows a cleaning device 7 for the nozzles 9 of a movable mold part 15, which cleans with compressed air 17 nozzles 9, which are located outside the conveying line 5. The cleaning device shown, both inner 21 and outer 31 soiling can be eliminated. The cleaning device 7 shown could also be used to check by means of compressed air 17 whether the nozzle is free of contaminants, in particular whether the cleaning was successful, whereby compressed air 17 can pass unhindered through the nozzle.

FIGS. 4a and 4b show, inter alia, a nozzle 9, next to which a cleaning device 7 is arranged. By the compressed air supply line 22, the compressed air 17 is supplied and exits through the compressed air outlet opening 23, wherein the compressed air 17 is passed to the outlet opening 16 in order to clean them from external contaminants 31. This cleaning by means of compressed air 17 can take place both inside and outside the delivery line 5.

The means 12 can furthermore be a means for mechanical cleaning, for example ultrasound or a brush, as shown in FIG. 5, which can be arranged inside or outside the conveying line 5. The agent 12 may also be water, detergents,

Solvent or mixtures act. For example, the nozzle, in particular the outlet opening 16 and / or the nozzle bore 161, outside the delivery line by water, detergents, solvents or Mixtures thereof are cleaned, which eliminate internal 21 and external 31 soils.

Of course, a combination of the mentioned means 12 can be used and be advantageous.

It is particularly useful when the device 1 means 24 for

Determining the flow rate FI _{FZ of} the liquid additive 3, for example a flow meter, and means 26 for determining the

Delivery pressure P _{FZ of} the liquid additive 3, for example, a pressure gauge having.

Further, it is advantageous if the device 1 means 25 for determining the flow rate FI üse _D of the liquid additive 3, typically a flow meter, of at least one nozzle, in particular each nozzle has. Further, it is advantageous if the device 1 means 32 for

Determining the flow rate FI _{PM of} the powdery material 2, for example, a flow meter for powdered media having.

The apparatus 1 can furthermore have at least one control system 11 which has the flow rate FI _F z of the liquid additive 3 and / or the delivery pressure P _F z of the liquid admixture and / or the flow rate FI _{PM of} the powdery material 2 as the measured variable.

Advantageously, the at least one control system 11 as the measured variable to the delivery pressure P _F z of the liquid additive. It is particularly useful if the at least one

Control system 11 as a controlled variable at least one nozzle 9 switch on or off and / or can turn on or off as a controlled variable at least one cleaning device.

An increase in the delivery pressure P _F z indicates either a blockage in the introduction device 6 or an increase in the flow rate FI _FZ due to an increase in the flow rate FI _{PM of} the powdery material 2. Preferably, the control system 11 as a measured variable to the delivery pressure P _F z of the liquid additive. By using the delivery pressure P _{FZ of} the liquid additive 3 as a measured variable, a further nozzle 9 can be switched on when reaching a defined upper delivery pressure P _{FZ O} compared to normal or optimum operation as a control variable (cascade), whereupon the delivery pressure P _F z thanks to larger outlet area falls back into the normal value range P _F zo _P t and the spray pattern remains in a safe area. This means, among other things, that, for example, a desired flat jet does not emerge as a bundled jet or an uncontrolled spray pattern. Conversely, it works in case of drop in the delivery pressure PFZ analog.

Further, upon reaching a defined upper delivery pressure P _{FZ O} compared to normal or optimal operation as a controlled variable, a cleaning device 7 are switched on, whereupon the delivery pressure P _F z thanks to the removal of contamination in the event of internal or external pollution back to the normal value range P. _F zo _P t falls behind. The conveying of liquid additive within a normal value range P _{FZ o} p _t is advantageous in that the nozzles, in particular if they are flat jet nozzles, have a pressure range or flow range in which an optimum spray pattern is ensured. Outside the areas mentioned, contamination of the delivery device or the nozzles may occur, for example, or local supersaturation with liquid additive 3 in the delivery line 5. This would not be beneficial for a controllable introduction of liquid additive and a homogeneous distribution of the liquid additive onto the powdery material ,

An addition of the liquid additive 3 alone based on a determination of the flow rate FI _F z of the liquid additive as a measured variable would also be conceivable (more flow requires more open nozzles), but this would in the case of a blockage of a nozzle 9 no additional nozzle or a cleaning device switch on, which would promote the nozzles outside the normal value range P _F zo _P t. In addition, the delivery pressure P _F z could rise so far that the Insertion device would be damaged and the treatment of the pul deformed material with liquid additive would come to a standstill.

The determination of the flow rate FI _{PM of} the pulverulent material 2 can be carried out empirically or technically, for example by means of a flow meter for pulverulent media.

The mass ratio of added liquid additive 3 to powdery material 2 is typically 1:10 - 1: 1000, in particular from 1: 100 - 1: 500. By determining a maximum delivery pressure P _F z _{max of} the liquid

Additive 3 and switching off the promotion of the liquid additive upon reaching the maximum delivery pressure PFZ max, for example due to a blockage in the main supply line 81, damage to the introduction device 6 can be prevented. The determination of the flow rate _D FI üse of the liquid additive

3, typically just in front of a nozzle 9, can be done by means of simple flow sensors which only have to recognize large changes in the flow rate FI _nozzle and are therefore inexpensive. The flow rate FI üse _D can therefore be used for to detect internal or external contamination of the nozzles.

The control system 11 can therefore, as previously mentioned, also use the cleaning devices 7 and / or the use of the protective devices 13 as control variables. It is particularly advantageous if the control system 11 uses as control variables the mentioned devices as well as the supply, respectively the switching off of nozzles 9.

FIG. 6 shows an introduction device 6 and a cleaning device 7, which uses compressed air 17 as means 12. The introduction device 6 comprises a supply line 8 consisting of a main supply line 81 and secondary supply lines 82 and nozzles 9.

Furthermore, FIG. 6 shows means for determining the flow rate FI _F z 24 of the liquid additive 3, the delivery pressure P _FZ 26 of the liquid additive, the flow rate FI _PM 32 of the powdery material 2, and the flow rates FI _nozzle 25. The means 25 is typically a simple flow sensor as previously mentioned. The bypasses 82 further include a valve 27, typically a manually operable valve, and a 1 way valve 28. The cleaning device 7 has compressed air lines 30, which have 1-way valves 29 and can bring in the region of the secondary feed line 82 between the nozzle and 1-way valves 28 compressed air.

By the means 25 for determining the flow rate FI _DÜSΘ an internal or external pollution can be detected by the consequent drop in the flow rate FI _DÜSΘ . The control system can on the one hand connect an additional nozzle to the desired delivery pressure

P _FZ and / or to ensure the desired flow rate FI _F z, on the other hand, the affected secondary supply line 82 can be closed by closing the 1-way valve 28 and by opening the corresponding 1-way valves 29 compressed air 17 in the clogged secondary supply line

82 are left to clean the bypass and / or the nozzle.

Furthermore, the invention comprises a method for treating, in particular coating, powdery material 2 with at least one liquid additive 3, wherein the liquid additive 3 is brought into contact with the powdery material 2 via a previously described device 1.

In particular, the method comprises the steps: a. Conveying a powdery material 2 through a

Delivery line 5; b. Spraying the powdery material 2 with at least one liquid additive 3 in an amount which is proportional to the flow rate FI _{PM of} the powdery material.

Furthermore, it may be advantageous if the method additionally comprises the following step: c. Determining the flow rate FI _{PM of} the powdery material 2 and / or determining at least one delivery parameter FP _{FZ of} the liquid additive 3, wherein FP _FZ the two parameters flow rate FI _F z of the liquid additive 3 and delivery pressure P _F z of the liquid additive 3 comprises.

Preferably, the step comprises determining the flow rate FI _{PM of} the powdery material 2, determining the flow rate FI _F z of the liquid additive 3 and determining the delivery pressure P _F z of the liquid additive 3.

It is advantageous if the method additionally comprises at least one of the following steps: d. Cleaning of parts or the entire introduction device 6 by the cleaning device 7, if at least one delivery parameter FP _{FZ of} the liquid additive 3 a

Limit value FP _FZ min falls below or exceeds a limit FP _{FZ ma} χ, in particular if the delivery pressure P _{FZ of} the liquid additive 3 exceeds a limit P _{FZ ma} χ and / or e. Cleaning of parts or the entire introduction device 6 by the cleaning device 7 at regular intervals.

It is also advantageous if the method additionally comprises at least one of the following steps: f. Arranging a further nozzle 9 in the delivery line 5, if at least one delivery parameter FP _{FZ of} the liquid additive 3 falls below a limit FP _FZ min or exceeds a limit FP _{FZ ma} χ, especially if the delivery pressure P _{FZ of} the liquid additive 3 a limit P _{FZ max} exceeds and / or g. Replacing a nozzle 9 in the delivery line 5 by another nozzle in the delivery line 5, if at least one delivery parameter FP _{FZ of} the liquid additive 3 a Limit value FP _F z min falls below or exceeds a limit value FP _F z max, in particular if the delivery pressure P _F z of the liquid additive 3 exceeds a threshold value PFZmax.

It is further advantageous if the method additionally comprises at least one of the following steps: h. Measuring the flow rate FI _D üse the at least one nozzle 9, via which the liquid additive 3 is sprayed onto the powdery material 2; and i. Arranging the nozzle 9 outside the delivery line 5 and / or

Cleaning the said nozzle by the cleaning device 7, if the nozzle in step h) below a limit FI _D nozzle min.

Furthermore, it may be advantageous if the method additionally comprises the following steps: j. Measuring the delivery pressure P _{FZ of} the liquid additive 3; and k. Disable the promotion of the liquid additive 3 at

Reaching a maximum delivery pressure PFZ max

The advantages of the additional steps have been described previously.

Furthermore, the invention comprises the use of a device 1, as described above, for treating, in particular coating, powdery material 2 with at least one liquid additive 3.

Of course, the invention is not limited to the embodiments shown and described. LIST OF REFERENCE NUMBERS

1 device

2 Powdery material

3 Liquid additive

4 conveyor

5 delivery line 6 introduction device

7 cleaning device

8 supply line

81 Main supply line

82 Secondary supply 9 nozzles

10 pump

11 control system

12 means for cleaning the introduction device

13 Protective device 14 Air curtain

141 Blower of the air curtain

15 movable molding

16 Outlet nozzle 161 Nozzle hole 17 Compressed air

18 compressor

19 Opening in the delivery line

20 Dust of powdered material

21 Internal contamination 22 Compressed air supply line

23 compressed air outlet opening

24 means for determining the flow rate FI _F z of the liquid additive 25 means for determining the flow rate of the liquid additive FI _nozzle of the nozzle.

26 means for determining the delivery pressure P _{FZ of} the liquid additive 27 valve

28 1-way valve supply line

29 1-way valve compressed air

30 compressed air line

31 Outer pollution 32 Fluid flow rate determiner FI _PM of powdered material

Claims

claims

1. Device (1) for treating, in particular coating, of pulverulent material (2) with at least one liquid additive (3) comprising a conveying device (4) which contains at least one delivery line (5) through which the powdery material (2 ), at least one introduction device (6) for introducing the liquid additive (3) into the at least one delivery line comprising the powdery material, characterized in that the device (1) at least one cleaning device (7) for cleaning the introduction device (6) and in that the introduction device (6) comprises a feed line (8) and at least two nozzles (9), in each case via at least one nozzle (9) the liquid additive (3) in the feed line (5) and the powdered material inserted is.

2. Device according to claim 1, characterized in that the device (1) at least one control system (11), which as a measured variable, the flow rate FI _F z of the liquid additive (3) and / or the delivery pressure P _F z of the liquid additive ( 3) and / or the flow rate FI _{PM of} the powdery material (2).

3. Device according to one of the preceding claims, characterized in that the device (1) comprises means (24) for determining the flow rate FI _F z of the liquid additive (3) and means (26) for determining the delivery pressure P _{FZ of} the liquid additive ( 3) and optionally means (32) for determining the flow rate FI _{PM of} the powdery material (2).

4. Device according to one of the preceding claims, characterized in that the cleaning device (7) comprises means (12) for cleaning the introduction device (6), which is selected from the group consisting of sieve, solvent, compressed air, mechanical tool and ultrasound , in particular compressed air.

5. Device according to one of the preceding claims, characterized in that the cleaning device (7) cleans parts or the entire introduction device (6) when needed and / or temporally permanently or at regular intervals.

6. Device according to one of the preceding claims, characterized in that at least one of the nozzles (9) has a protective device (13), wherein the protective device (13) in the conveying line (5) is arranged.

7. The device according to claim 6, characterized in that it is in the protective device (13) to a cover or an air curtain (14), in particular an air curtain is.

8. Device according to one of the preceding claims, characterized in that at least one of the nozzles (9) in the conveying line (5) in and out is arranged to be movable.

9. Device according to one of the preceding claims, characterized in that at least two nozzles (9) of the introduction device (6) on a movable mold part (15) are arranged, wherein the movable mold part (15) is preferably round, oval or angular.

10. Device according to one of the preceding claims, characterized in that the conveying line (5) is an air conveyor trough.

11.Vorrichtung according to one of the preceding claims, characterized in that the powdery material (2) comprises at least one binder, preferably selected from

Group consisting of cement, mortar, gypsum, silica fume, fly ash,

Slag and blastfurnace slag or a mixture thereof.

12. Device according to one of the preceding claims, characterized in that the at least one liquid additive (3) is selected from the group consisting of dispersant, condenser, flow agent, retarder, accelerator,

Stabilizer, shrinkage reducer, air entraining agent and

Corrosion inhibitor or a mixture thereof.

13. A method for treating, in particular coating, of powdery material (2) with at least one liquid

Additive (3), characterized in that the liquid additive (3) via a device (1) according to one of the preceding claims with the powdery material (2) is brought into contact.

14. The method according to claim 13, comprising the steps: a. Conveying a powdery material (2) through a delivery line (5); b. Spraying the powdery material (2) with at least one liquid additive (3) in an amount which is proportional to the flow rate FI _{PM of} the powdery material; and optionally c. Determining the flow rate FI _{PM of} the powdery material (2) and / or determining at least one delivery parameter

FP _{FZ of} the liquid additive (3), wherein FP _F z comprises the two parameters flow rate FI _F z of the liquid additive (3) and delivery pressure P _F z of the liquid additive (3).

15. The method according to claim 14, comprising the steps: d. Cleaning of parts or the entire introduction device (6) by the cleaning device (7), if at least one delivery parameter FP _F z of the liquid additive (3) a Limit value FP _{FZ m} i _n below or exceeds a limit value FP _{FZ max} , in particular if the delivery pressure P _{FZ of} the liquid additive (3) exceeds a limit P _F z max and / or cleaning parts or the entire introduction device (6) by the cleaning device (7) at regular intervals.