DE102021201876A1 - Textile treatment apparatus and method - Google Patents

Abstract

The invention relates to a device (100) for dosing a pourable substance into an aqueous treatment liquor for treating a textile substrate. The device comprises a storage container (102) for the substance, a mixing unit (104) which has an inlet (106) and an outlet (108) for the treatment liquor and a sprinkling opening (188) for the substance, the inlet (106) and the outlet (108) of the mixing unit (104) can be connected to a wet treatment tank of a textile treatment plant, a regulated conveyor system (114) connected to the storage tank (102) for transporting the substance from the storage tank (102) to the litter opening (188), and a control unit which is connected to the conveyor system (114) and is set up to output a control signal to the conveyor system (114). The invention also relates to a textile treatment plant with such a device (100), the use of the device (100) and a textile treatment method in which at least one pourable substance is metered in a controlled manner into an aqueous treatment liquor circulating in a circuit of a textile treatment plant for the treatment of a textile substrate .

Description

The invention relates to a device for metering a substance into an aqueous treatment liquor for the treatment, in particular dyeing, of a textile substrate.

It is known that various dye systems are used for dyeing cellulosic textiles, such as reactive dyes, direct dyes or vat dyes. Cellulose exists in textiles in different forms. Cotton, linen, jute, viscose, cupro or the like may be mentioned here as an example.

Salt, especially in the form of sodium chloride or sodium sulphate, is added to all conventional dyeing processes used to finish cellulosic textiles and mixtures thereof in order to shift the concentration ratio in the dye liquor in a targeted manner and thereby increase and control the extraction rate of the dye onto the textile to control. The most common class of dyes for cellulosic textiles today is reactive dyes.

After leaving the dyebath on the textile, dyes in this class of dyes need to be fixed on the textile or chemically react with the textile, which can be controlled by changing the temperature and pH value. The pH changing chemicals are typically sodium carbonate and sodium hydroxide. Often these chemicals are only used to adjust the appropriate pH. Some dyeing recipes contain pH buffers, which ensure that the desired pH value is maintained in a stable manner.

The liquid for treating the textile substrate that is present in the dyeing installation at the respective point in time is referred to here as the treatment liquor. The term therefore includes pure water at the beginning of the treatment and the finished dyeing solution after all components have been added and dissolved.

In particular, thread-like, tape-like or flat substrates of finite length and in the form of an "endless" strand of tape or a coil of tape come into consideration as a textile substrate. This includes loose fibres, textiles on spools, hanks and other textile products of any presentation in which cellulosic textiles may be present.

The dyeing process, which is known per se, is described below, beginning with the textile raw material. The entire dyeing process is essentially divided into three steps: pre-treatment, the actual dyeing and post-treatment. In particular, the pre-treatment can also be carried out completely separately from the actual coloring, for example in a different system.

pretreatment

The cellulosic textile raw material is coated with natural wax. These have to be removed in a first alkaline pre-treatment step in order to enable the goods to absorb water and thus dyes. In addition to the optimized wettability of the goods, the pre-treatment step swells the cellulose, which means that it can absorb even more water. The pre-treatment takes place at relatively high temperatures (85°C - 110°C). The alkaline pH is adjusted by adding caustic soda. The waxes and oils on the cotton raw material are saponified and used as surfactants. In the resulting soap bath, these have an emulsifying effect on the coarse contamination of the goods and enable an improved cleaning effect. With the help of the pre-treatment, the nuances in the inherent color and physical properties of the different batches of cotton are evened out as much as possible in order to enable reproducible dyeing results. In addition, the goods are bleached with the help of hydrogen peroxide, primarily to achieve light shades of colour. This destroys the natural dyes in the cotton and the goods then appear whiter. At the end of the pre-treatment, the pH value must be neutralized again with the help of an acid, usually highly concentrated, for example 66% acetic acid. In addition, the bleach must be removed. These extensive rinsing processes are necessary so that no chemicals are carried over into the subsequent dyeing process.

coloring

The coloring itself consists of two functional steps, the dye extraction or migration and the fixation. In conventional processes in so-called jet dyeing plants, the dyeing takes place at a liquor ratio of at least 1:4, rather 1:5 to 1:6 or more, the liquor ratio being the ratio of the mass of the textile substrate to be treated in kg and the volume of the treatment liquor required for this is denoted in L. As is conventional, a liquor ratio with a comparatively higher volume of treatment liquor, for example a liquor ratio of 1:6 compared to a liquor ratio of 1:5, is also referred to here, contrary to the numerical notation, as the "higher liquor ratio". Depending on the desired shade and its saturation, appropriate amounts of salts (sodium chloride or sodium sulfate) are kept in vessels at the plant, and from there into run the dyeing plant. The salt is added dry or dissolved to make it easier to transport. In newer plants with a dry supply of salt, the required amount of salt is kept in a funnel-shaped container which, driven by a shaking movement, is completely emptied into the circulation of the treatment liquor. The higher the saturation of the hue, the higher the salt concentration must be during dyeing in conventional dyeing processes. This is attributed to the fact that an increase in the concentration of the electrolytes in the form of sodium ions in the solution leads to an improvement in the dye extraction during the reactive dyeing of cellulosic textiles. After the desired salt concentration has been reached, the pre-dissolved dye is metered into the dye liquor over a certain extended period of time. As an alternative to the process described above, the treatment liquor with salt and dye can also be kept ready in a preparation vessel and fed into the dyeing plant. After the dye has been dosed or the treatment liquor has been fed in as a whole, the goods are rotated in the dyeing plant for a certain period of time, the so-called dye migration phase, so that the dye-salt mixture can be evenly distributed in the goods.

After the dye has settled evenly on the goods, i.e. the migration phase is over, it must be fixed there. With reactive dyes, this occurs through a chemical reaction of the dye with the functional groups of the cellulosic textile. The intensity and speed of this chemical reaction depends on the reactive dye, the functional groups (hydroxyl groups) of the cellulosic textile, the temperature and the alkaline pH value (pH value > 7). For most reactive dyeing systems, an isothermal temperature profile is chosen during the migration and fixation phase. The alkalinity of the dye liquor is slowly adjusted from neutral to a pH value of around 11 by metering in pre-dissolved sodium carbonate. Liquid (33%) sodium hydroxide is then added to the dyeing liquor, usually over an extended dosing phase. This slowly raises the pH to around 12.5 to 13. The reaction optimum of most reactive dyes lies in this pH range. The careful raising of the pH regulates the chemical reaction between the dye and the functional group of the cellulosic textile in order to ensure an evenly distributed chemical reaction on the textile substrate and thus an even dyeing pattern. Another reason for regulating the reactivity of the dye is that under optimal conditions (temperature & pH value) for the fixation, the reactive dye also reacts with the solubility products of water (water → hydronium ions + hydroxyl ions). This process is called hydrolyzation of the dye. The hydrolyzed dye molecules are no longer available for a reaction with the functional groups of the cellulosic textile and thus for the dyeing process of the textile. The hydrolysis reaction can be largely minimized by slowly increasing the pH value and controlling the temperature.

post-treatment

After the reactive dye has been fixed, excess and hydrolyzed dye residues and the dissolved salt must be removed. The salt concentration in the textile is reduced by repeatedly rinsing the dyed textile in warm water. The amount of salt used determines the number of these baths and the volumes of water used. Water consumption can be reduced with the salt-free dyeing mentioned below. As soon as the salt has been removed, the textile goods, which are alkaline from the treatment with caustic soda from the dyeing process, are neutralized again with the help of an acid, usually highly concentrated, e.g. 66% acetic acid. Otherwise, the subsequent hot soapy baths would partially remove the previously fixed dye and change the color tone. Due to the hot soaping in a pH-neutral medium, only unfixed dye residues are emulsified on the goods and can be drained off. This process is mainly necessary to achieve demanding fastnesses (fastness to washing, perspiration, rubbing) and takes place in multiple applications, especially with dark shades. This is followed by several, typically 2 to 3, warm rinsing baths to remove any emulsified dye residue. The last rinsing bath of the post-treatment can contain a low concentration of acetic acid and optionally softeners for a pleasant hand of the dyed textile.

More recent development work has set itself the goal of completely dispensing with the addition of salt in the case of a particularly low liquor ratio, i.e. more textile substrate in relation to the treatment liquor than before. As an example, reference is made to the international disclosure document WO 2014/155101 A1 referred. One advantage of this development is that as little water as possible is used directly in the dyeing process, i.e. when the dye is extracted from the dye liquor onto the textile and when the dye is fixed on the textile, on the one hand and when the textile is subsequently rinsed out to remove salt on the other.

The object of the invention is against this background, a basis for an environmentally friendly and at the same time to create economic coloring on an industrial scale.

The object is achieved, among other things, by a device for metering a pourable substance into an aqueous treatment liquor for the treatment, in particular dyeing, of a textile substrate, which device has a storage container for the pourable substance, a mixing unit that has an inlet and an outlet for the aqueous treatment liquor and a sprinkling opening for the pourable substance, wherein the inlet and outlet of the mixing unit can be connected directly or indirectly to a wet treatment tank of a textile treatment plant, a regulated conveyor system connected to the storage tank for transporting the pourable substance from the storage tank to the sprinkling opening, and a the control unit which is connected to the regulated conveying system and which is set up to output a control signal to the regulatable conveying system.

In the broadest sense, the “wet treatment tank” is the part of a textile treatment plant in which the treatment liquor and the textile substrate to be treated are brought together for the purpose of treatment. In a dyeing treatment, the wet treatment tank is also referred to as a "dyeing kettle". Such containers are known. Their mechanical details are therefore not explained here.

While in conventional methods sodium carbonate in liquid form, i.e. pre-dissolved, was metered in for the purpose of fixing the dye on the textile, the invention enables the sodium carbonate to be added by means of the device according to the invention which can be connected to the wet treatment tank of a textile treatment plant, i.e. is integrated into the circuit of the treatment liquor within the dyeing machine sprinkle directly into the treatment or dyeing liquor for dosing in pourable, for example granular or powder form. With this procedure, also referred to herein as “dry dosing”, pre-dissolving outside of the dye liquor is no longer necessary, which means that water consumption can be reduced while the exact dosing at least remains the same.

It is well known that sodium carbonate is hygroscopic. Sodium carbonate and hygroscopic substances in general therefore tend to form lumps when in contact with moisture. Since they already contain water in this state, it is also possible that a small part of the substance is dissolved on the surface. However, for the most part, the substance is still in the solid state of aggregation. In this state, too, the substance is “pourable” within the meaning of the invention. “Pourable” is generally understood to mean both non-cohesive and cohesive bulk materials. In addition to largely undissolved substances, the term “pourable” also includes, in particular, powdery or granular substances. Terms used synonymously herein are "solid", "dry" and "in the solid state of aggregation". In this form, the substance can also be referred to as bulk material.

Especially with new or future dyeing processes of purely cellulosic textiles or textile fiber mixtures with a cellulosic content, which help to reduce the addition of salt, the device according to the invention can be used in the manner described for dry dosing of the sodium carbonate in order to additionally reduce the water requirement in a practicable manner to reduce and to arrive at a lower liquor ratio. With decreasing water content, i. H. As the concentration of dye increases, care must generally be taken to ensure precise dosing, which is precisely ensured by the dry dosing.

This is just one possible application example in which water can be saved by the dosing device according to the invention. The device can also be used in particular for retrofitting conventional or existing dyeing machines, ie also for those in which the dye extract takes place with the addition of salt, in order to save water. In particular, the dosing device according to the invention can also be used for adding the salt itself to the treatment liquor, as a result of which pre-dissolving can then be dispensed with in this process step and the water consumption can thus be reduced. Furthermore, the device also enables mixtures of salt and sodium carbonate to be dosed dry.

Even if coloring represents a main application of the present invention above and in the following description of preferred embodiments, its application is not limited thereto. The invention can be used in many other areas of textile finishing. For example, the device can be used for the controlled metering in of caustic soda in the form of flakes as a pourable substance during the pretreatment.

In general, the device according to the invention is therefore not limited to dyeing, but can be used to supply any free-flowing chemicals for the treatment or finishing of a textile substrate in order to save water. The dry dosing according to the invention is reproducible due to the controlled transport of chemicals that can be poured dosing curves safely and enables high-quality, uniform and reproducible staining results.

Various mechanical or pneumatic feed elements, such as vacuum conveying systems such as venturi tubes, can be considered as the controllable conveying system. In the latter, the liquid treatment liquor is guided through a nozzle arrangement to generate a negative pressure, with the volume flow of the treatment liquor being controlled via a control valve. The volume flow of the treatment liquor influences the pressure in a volume surrounding the nozzle arrangement. Depending on the setting of the control valve, the substance that is added dry is drawn off to a greater or lesser extent from a storage container that is connected to the volume, ie it is added in a controlled manner.

The conveying system preferably comprises a conveying screw which is set up to transport the pourable substance from the storage container to the litter opening. The screw conveyor is part of a mechanical conveyor system, which is particularly easy and precisely controllable.

The conveying system advantageously has an adjustable drive (for example for the conveying screw) which is connected to the control unit.

The storage container or the conveying system preferably comprises a measuring unit for determining the quantity of the pourable substance contained in the storage container or removed from it. In both cases, the metered quantity of the pourable substance can be determined directly or indirectly. In particular, this can be a gravimetric measuring unit for detecting the mass or a volumetric measuring unit for detecting the volume of the substance removed or contained in the storage container. A volumetric measuring unit can be provided, for example, by an ultrasonic or laser measuring device for determining the fill level of the substance in the reservoir or the flow of the substance through the conveyor system or an associated connector at a suitable measuring point.

The measuring unit is preferably a weighing unit which is set up to determine the mass of the pourable substance contained in the storage container. This is a gravimetric unit of measurement. The weighing unit can be implemented by weighing cells arranged on the storage container, which monitor the total mass of the storage container in real time and, derived from this, the mass of the pourable substance conveyed to the mixing unit in a specific unit of time.

Particularly preferably, the measuring unit is connected to the control unit and set up to output a measured variable, i.e. the detected quantity (mass or volume) of the removed or pourable substance contained, as a control variable to the control unit, and the control unit is set up to transmit the control signal to the conveyor system , in particular to the controllable drive, to vary depending on the measured variable, for example to increase or throttle the flow rate if necessary.

For this purpose, the control unit can be connected to an internal or external memory device and/or to an input terminal on site or remotely, or it can be connected and set up to request parameters from the memory unit and/or the input terminal, which can, for example, be in the form of a preprogrammed dosing profile (quantity Time diagram) are stored. These parameters serve as setpoints and can be processed together with the measured or controlled variable output by the measuring unit to form control signals for the controllable drive.

If, in the example described above, the measurement or monitoring by the weighing cells shows that the feed rates deviate from a target value, the control unit can adjust the frequency of the feed screw during dosing until the dosing is back to target.

The desired small amount of water leads to a higher concentration of additives (dyes, salts, sodium carbonate, sodium hydroxide) in the treatment liquor. The invention takes account of the finding that even slight fluctuations in the concentration of the additives are more noticeable in the dyeing result than with a higher liquor ratio. It is therefore necessary, especially with dry dosing, to keep the dosed quantities within narrow limits, for which the measuring unit in connection with the control and the conveyor system creates the basis.

Alternative or additional parameters or control variables in addition to the amount of powdered or granular substance removed and a metering profile can be, for example, fill levels of the treatment liquor or the conductivity of the treatment liquor, which is determined inside the device or elsewhere in the textile treatment system, i.e. outside the device, and by there to be fed to the control unit. For example, the level of the treatment liquor directly in the wet treatment tank Textile treatment plant are measured or the conductivity of the treatment liquor in the main circuit of the wet treatment tank. The dosing duration, the total dosing quantity, physical or chemical properties of the treatment liquor (e.g. conductivity) and the respective target values and the like also come into consideration.

Another advantageous contribution to controlled dosing is if the storage container comprises a stirring element which is set up to keep the pourable substance contained in the storage container in motion. Such a stirring element ensures that no cavities form in the storage container, especially with substances that tend to clump together, and that the fill level in the storage container is equalized and the filling material completely covers the bottom of the storage container. In addition, the stirring element preferably has a geometry that promotes transport of the substance within the storage container to an outlet opening connected to the conveyor system. As a result of these measures, the stirring element ensures a continuous discharge from the reservoir overall, even when the filling material is not very free-flowing.

According to an advantageous development of the invention, the mixing unit comprises a pre-dissolving tank with an inlet for the treatment liquor, the inlet being fluidically connectable to the inlet and opening into the pre-dissolving tank in such a way that the treatment liquor introduced via the inlet circulates in the pre-dissolving tank. This can be achieved, for example, by a pre-dissolving tank with a round inner contour, with the inlet opening out as tangentially as possible to the inner contour. As an alternative to a pre-dissolving tank with a tangential inlet, a pre-dissolving tank with a magnetic stirrer can also be provided in order to circulate the treatment liquor.

The sprinkling opening is preferably arranged above a section of the treatment liquor circulating in the pre-dissolving tank. The pourable substance to be dosed is transported with the help of the conveyor system from the storage container to the sprinkling opening and, driven by gravity, falls from there into the dye liquor circulating in the pre-dissolving container. Due to the movement of the dye liquor, shearing forces act, which quickly ensure a homogeneous distribution of the solid substance. There are preferably one or more sieves in the sprinkling opening, which, particularly in the case of powdered substances, counteract the formation of agglomerates or clumping that is favored by the conveyance.

Furthermore, the pre-dissolving container preferably has a bottom outlet and the mixing unit below the pre-dissolving container has an injection unit which is fluidically connected to the outlet of the pre-dissolving container. Particularly preferably, the bottom of the pre-dissolving tank is designed to taper in a funnel shape towards the outlet. This ensures that the treatment liquor with the dosed solid substance drains from the pre-dissolving tank into the injection unit largely without residue. Since the solid substances in question usually do not dissolve completely in the treatment liquor during the comparatively short residence time in the pre-dissolving tank, a mixture of substances with a solid and liquid phase emerges through the outlet.

Advantageously, the injection unit has a draw-off volume that is fluidically connected to the outlet of the pre-dissolving tank, and in the draw-off volume is arranged an injector nozzle that can be fluidly connected to the inlet of the mixing unit and is set up to generate a directed flow of the treatment liquor within the draw-off volume. As a result, based on the principle of the Venturi tube, a hydrostatic pressure that is reduced compared to the ambient pressure is generated at the outlet opening of the injector nozzle. Shear forces occur again here, which further homogenize the mixture. It is therefore a two-stage mixing process.

The outlet volume is connected to the outlet of the mixing unit. In this way, the treatment liquor can be fed back into the cycle of the textile treatment plant after dosing.

To generate the directed flow of the treatment liquor, the device preferably has a pressure pump between the inlet of the mixing unit and the injector nozzle. The pressure pump is in turn preferably connected to the control unit.

According to an advantageous development, the device has a liquid container for a liquid to be added to the dye liquor and a supply line fluidically connecting the liquid container with the mixing unit, in the embodiment described above with the pre-dissolving container, in which a liquid dosing device is switched on. This precaution can be used, for example, to add pre-dissolved sodium hydroxide. The liquid is fed into the predissolving tank and fed into the circulating treatment liquor by gravity. The supply line advantageously opens out over a section of the treatment liquor circulating in the pre-dissolving tank. The liquid will in this way also distributed homogeneously in the treatment liquor by the two-stage mixing process. In this way, the device can be combined with liquid metering systems without additional pressure pumps to form a cost-conscious metering system. Here, too, the dosing must be exact, with suitable dosing devices for liquids being known in dyeing technology. The liquid metering device is formed by a metering valve. The metering valve can itself be regulated and connected or can be connected to the control unit.

The object is also achieved by a textile treatment plant for the treatment, in particular dyeing, of textile substrates, which textile treatment plant comprises a device of the type described above and a wet treatment tank for receiving and treating the textile substrate, the wet treatment tank being directly or indirectly connected to the inlet and outlet of the dissolving tank can be connected in order to transfer the treatment liquor, based on the direction of flow, into the wet treatment tank before dosing.

In this way, the device is integrated into the circuit of the treatment liquor. In this context, directly or indirectly connectable means that there is a pipeline connection, possibly with the interposition of other elements of the textile treatment system such as feed pumps, heating devices or the like, between the wet treatment tank and the device, which can be opened or closed by means of valves.

The control unit is preferably part of a programmable controller, in particular a programmable logic controller, of the textile treatment plant. This simplifies the technical control connection of the device to the textile treatment plant. In this way, in particular, other parameters within the textile treatment system, such as measured filling level values or measured conductivity values, can be used to control or regulate the device. For example, the fill level of the treatment liquor in the wet treatment tank can serve as a control or regulation variable for switching the pressure pump on and/or off to generate the directed flow of the treatment liquor in order to avert damage to the system.

The object is also achieved through the use of a device of the type described above in a textile treatment plant for metering in one or more pourable substances into an aqueous treatment liquor for the treatment of a textile substrate.

The pourable substance is preferably selected from the group of organic and inorganic salts. Organic sodium salts, such as sodium chloride, sodium sulfate, and inorganic salts, such as sodium carbonate, are particularly suitable. In principle, any conveyable solids for the production of liquid solutions or dispersions in water can be metered in the manner according to the invention.

The object is finally achieved by a textile treatment process in which at least one pourable substance is metered in a controlled manner into an aqueous treatment liquor circulating in a circuit of a textile treatment plant for the treatment, in particular dyeing, of a textile substrate. The pourable substance to be added is preferably a substance from the selection mentioned above. The regulated dosing is preferably carried out by means of a regulated conveyor system connected to the storage container for transporting the pourable substance from a storage container to the litter opening of a mixing unit and by means of a control unit connected to the regulated conveyor system, which outputs a control signal to the controllable conveyor system depending on a measured variable. The measured variable is preferably the quantity of the pourable substance contained in the storage container or removed from it.

Depending on the substance to be dosed, the transport speed of the treatment liquor in the cycle of the textile treatment plant is preferably adjusted by means of a programmable controller of the textile treatment plant. For example, solid sodium carbonate can be dosed in this way over 20 - 30 minutes.

In particular, the textile treatment process according to the invention comprises the dyeing of cellulose with reactive dye using salt (sodium chloride or sodium sulphate) to improve dye exhaustion and also without the use of salt, as described above in each case. Furthermore, the textile treatment method according to the invention preferably comprises a pre-treatment and/or an after-treatment as described above.

The method preferably includes dosing solid sodium carbonate in powder form into the treatment liquor, as a result of which the concentration of sodium ions (electrolyte) and the pH value are increased slowly and uniformly, preferably to a pH value of approximately 11.

• 1 eine Seitenansicht einer Ausführungsform der erfindungsgemäßen Vorrichtung zur Trockendosierung;
• 2 eine Unteransicht der Ausführungsform;
• 3 eine zweite, gegenüber der ersten gedrehte perspektivische Ansicht der Ausführungsform;
• 4 eine dritte weiter gedrehte perspektivische Ansicht der Ausführungsform;
• 5 eine perspektivische und teiltransparente Ansicht des Vorratsbehälters der Ausführungsform;
• 6 eine perspektivische und teiltransparente Ansicht des Fördersystems der Ausführungsform;
• 7 eine perspektivische und teiltransparente Ansicht der Mischeinheit der Ausführungsform und
• 8 eine schematische Darstellung einer Ausführungsform der erfindungsgemäßen Vorrichtung zur Trockendosierung.

Further advantageous configurations and advantages of the invention are explained below with reference to figure drawings. Show in it:

• 1 a side view of an embodiment of the device according to the invention for dry dosing;
• 2 a bottom view of the embodiment;
• 3 a second perspective view of the embodiment rotated with respect to the first;
• 4 a third further rotated perspective view of the embodiment;
• 5 a perspective and partially transparent view of the storage container of the embodiment;
• 6 a perspective and partially transparent view of the conveyor system of the embodiment;
• 7 a perspective and partially transparent view of the mixing unit of the embodiment and
• 8th a schematic representation of an embodiment of the device according to the invention for dry dosing.

In the 1 until 4 the same exemplary embodiment of the device 100 according to the invention for dry dosing is shown in full in each case. Reference is made to these figures together below.

The device 100 comprises a storage container 102 for the pourable substance in the upper area and a connected mixing unit 104 in the lower area. The mixing unit 104 has an inlet 106 and an outlet 108 for the aqueous treatment liquor. The inlet 106 and the outlet 108 of the mixing unit 104 can be connected to a wet treatment tank of a textile treatment plant (not shown). The flow direction of the treatment liquor is indicated by the arrows 110 and 112.

Below the storage container 102, the device 100 also comprises a regulated conveyor system 114, which is connected to the storage container 102, for the controlled transport of the pourable substance from the storage container 102 to the mixing unit 104.

To illustrate the internal elements, the peripheral wall of the reservoir is 102 in 5 displayed transparently. The reservoir 102 is generally cylindrical in shape with a cylindrical peripheral wall 120, a planar bottom wall 122, and a partially openable lid 124. As shown in FIG. An outlet opening 126 is provided in the bottom wall 122 and is covered with a grid. Immediately above the bottom wall 122 there is a stirring element 128 which can be rotated about the cylinder axis and which is moved by a drive motor 130 arranged below the vessel. The stirring element 128 keeps the filling material, ie the dry substrate, in the storage container 102 in motion and thus ensures that no cavities form in the storage container 102 and that the fill level in the storage container 102 is evened out. This ensures that the filling material completely covers the bottom wall 122 . The agitator 128 has two arcuate blades and is rotated toward the concave front thereof. This geometry also favors a radial transport of the filling material towards the inner apex of the arc, which is radially at a distance from the axis of rotation, in which it sweeps over the outlet opening 126 . The cover grid in the outlet opening 126 interacts with the stirring element 128 in that it increases the shearing in the plane of the outlet opening 126 and thus counteracts the formation of agglomerates and lumps. As a result of these measures, the stirring element 128 as a whole ensures continuous transport even when the filling material is not free-flowing. In this way, a continuous discharge of filling material through the outlet opening 126 from the storage container 102 into the conveyor system 114 located underneath is ensured.

The reservoir 102 is supported on three stands 140 . On each post 140, as well as on the outside of the cylinder wall 120, are paired opposed flanges 142 and 144. More specifically, the paired opposed flanges 142 and 144 are slightly circumferentially offset from one another. A weighing cell 146 is located between each pair of flanges 142 , 144 . In this exemplary embodiment, the totality of the three weighing cells 146 therefore forms the measuring unit in the form of a weighing unit. The weighing unit is thus set up to determine the mass of the substance contained in the storage container 102 and thus indirectly the mass of the powdered or granular substance removed from the storage container 102 .

In 6 1, the conveyor system 114 is shown in detail and partially semi-transparent to illustrate internal elements. The delivery system comprises a housing 150 which has a filler neck 152 on its upper side which is connected to the outlet opening 126 of the storage container 102 by means of a flange 154 . In the housing 150 there is a screw conveyor 156 whose conveying direction is indicated by an arrow 158 is. The screw conveyor 156 is driven by an adjustable drive 160 consisting of a drive motor 162 and a gear 164 for the purpose of adjusting the motor speed. The drive 160 is connected to a control unit (not shown), which outputs a control signal to the controllable drive 160 as a function of certain process parameters, ie open-loop or closed-loop control variables, in order to control the speed and thus the flow rate. In the present case, the specific mass of the pourable substance removed from the storage container 102 comes into consideration as the controlled variable. The screw conveyor 156 accordingly transports the pourable substance falling out of the reservoir 102 with a regulated flow rate in the horizontal direction 158 to the end of the housing 150 to which a housing 166 of a discharge chute is flanged. At the end of the housing 150 there is an outlet opening 168 which communicates fluidly with the discharge chute. Optionally, one or more additional screens can be provided in the outlet opening 168 in order to counteract any agglomeration or clumping of the pourable substance. Located in the ejection chute opposite the outlet opening 168 is a closing element 172 that can be moved by means of an actuator 170 and with which the outlet opening 168 can be closed after the dosing process in order to protect the substance stored in the reservoir 102 and the conveyor system 114, in particular from the ingress of moisture. After the substance has exited the outlet opening 168, the substance falls through the discharge chute into the mixing unit 104 located below.

The mixing unit 104 is in 7 also partially semi-transparent to illustrate internal elements. The mixing unit 104 includes a pre-dissolving container 180 with a cylindrical peripheral wall 182, a funnel-shaped bottom wall 184 and a cover 186. In the cover 186 there is a sprinkling opening 188 into which the lower end of the housing 166 opens. Driven by gravity, the solid substance falls through the litter opening 188 into the pre-dissolving container 180 . One or more sieves can also be located in the sprinkling opening 188, which counteract the formation of agglomerates or clumping of the solid substances favored by the conveyance.

In this example, the pre-dissolving tank 180 is provided with three inlets 190 for the treatment liquor. Each inlet 190 is connected to an annular channel 192 for evenly distributing the flow of liquid to the inlets 190 . The annular channel 192 is in turn fluidically connected to the inlet 106 via a connecting pipe 194 . The flow can be controlled by a valve 196 built into the connecting tube 194 . The three inlets 190 each open into the pre-dissolving tank 180 in such a way that the treatment liquor introduced via them circulates in the pre-dissolving tank 180, in the present case approximately tangentially. Depending on the geometry and arrangement of the preliminary dissolving tank 180 and the inlets 190, one inlet 190 can also be sufficient to generate circulation. However, two, four or more inlets 190 can also prove to be suitable. The sprinkling opening 188 is consequently arranged above a section of the treatment liquor circulating in the pre-dissolving tank 180 . At the base of the funnel-shaped bottom wall 184, the pre-dissolving tank 180 has a bottom outlet 198 through which the circulating, pre-dissolved treatment liquor, i. H. the treatment liquor with the not yet completely dissolved, homogeneously distributed solid substance, flows off turbulently in a whirlpool-like manner.

The mixing unit 104 has an injection unit 200 below the pre-dissolving container 180 . This is fluidically connected to the outlet 198 of the pre-dissolving tank 180 . The injection unit 200 comprises an extraction volume 202 into which a pipe socket 203 connected to the outlet 198 of the pre-dissolving container 180 opens. An injector nozzle 206 fluidically connected to the inlet 106 of the mixing unit 104 via a connecting pipe 204 is arranged in the removal volume 202 . This has an outlet opening at its narrowest point. The inflow of the treatment liquor can also be controlled here by a valve 208 built into the connecting pipe 204 . Furthermore, a pressure pump 210 is built into the connecting pipe 204, as in FIG 8th shown schematically in order to provide a defined pressure for generating a directed flow of the treatment liquor within the removal volume 202.

Downstream of the outlet opening there is a diffuser 212 into which the stream flows. An annular gap is formed between the outlet opening of the nozzle 206 and the mouth of the diffuser 212, in which the stream has a narrowed cross section corresponding to the outlet opening. Due to the constricted flow, a hydrostatic pressure that is reduced compared to the ambient pressure is generated according to the principle of the Venturi tube, through which the mixture of substances running out of the pre-dissolving tank 180 is sucked in and entrained with the flow. Shear forces occur again here, which further homogenize the mixture.

A connecting pipe 214 , which is connected to the outlet 108 of the mixing unit 104 , is connected to the diffuser 212 on the outlet side, that is to say downstream. In this way, the treatment liquor is returned to the cycle of the textile treatment plant after dosing.

Furthermore, the device 100 in this exemplary embodiment of the invention has a liquid container 220 for a liquid to be added to the dye liquor. For this purpose, the liquid container 220 is connected to the pre-dissolving container 180 via a connecting line 222 . A flushing line 224 follows the connecting line 222 as a continuation thereof. A first branch 226 , a second branch 228 and a third branch 230 also branch off from the connecting line 222 . The third branch 230 also serves as a flushing line. Both flushing lines 224, 230 can be separated by means of a shut-off valve 232 each during operation of the system.

The liquid container 220 can be fluidically connected to the pre-dissolving container 180 via the first branch 226 and the second branch 228 . A liquid metering device in the form of a first metering valve 234 and a second metering valve 236 is located downstream of the branch points in the first and second branch 226, 228 in the direction of flow. These are used specifically for the controlled supply of liquid to the pre-dissolving tank 180 at different speeds and quantities. In the direction of flow behind the liquid metering devices, the branches 226, 228 and 230 are brought together again in a feed pipe 240, which opens out from above through the cover 186 into the pre-dissolving container 180. The connecting line 222 together with the two branches 226 and 228 and the feed pipe 240 thus form, in the sense of the claims, a feed line fluidically connecting the liquid container 220 to the pre-dissolving container 180, in which a liquid dosing device is switched on.

8th shows a schematic representation of the device according to the invention for dry dosing. The above explanations also refer to this illustration with reference to the same reference symbols.

Reference List

100

Device for dosing

102

reservoir

104

mixing unit

106

Intake

108

process

110

Flow direction arrow, upstream

112

Flow direction arrow, downstream

114

conveyor system

120

cylindrical peripheral wall

122

flat bottom wall

124

lid

126

exhaust port

128

agitator

130

drive motor

140

stand

142

flange

144

flange

146

load cell

150

Housing

152

filler neck

154

flange

156

Auger

158

flow direction arrow

160

drive

162

drive motor

164

transmission

166

enclosure

168

exit port

170

actuator

172

closure element

180

pre-dissolving tank

182

cylindrical peripheral wall

184

funnel-shaped bottom wall

186

lid

188

litter opening

190

inlet

192

ring canal

194

connecting tube

196

Valve

198

process

200

injection unit

202

purchase volume

204

connecting pipe

206

injector nozzle

208

Valve

210

pressure pump

212

diffuser

214

connecting pipe

220

liquid container

222

connection line

224

purge line

226

first turn

228

second turn

230

third turn

232

shut-off valve

234

first dosing valve

236

second dosing valve

240

feed tube

QUOTES INCLUDED IN DESCRIPTION

This list of the documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• WO 2014/155101 A1 [0012]

Claims (18)

Device (100) for metering a pourable substance into an aqueous treatment liquor for the treatment, in particular dyeing, of a textile substrate, which device has: a storage container (102) for the pourable substance, a mixing unit (104) which has an inlet (106) and an outlet (108) for the aqueous treatment liquor and a sprinkling opening (188) for the pourable substance, the inlet (106) and the outlet (108) of the mixing unit (104 ) can be connected to a wet treatment tank of a textile treatment plant, a controlled conveyor system (114) connected to the storage container (102) for transporting the pourable substance from the storage container (102) to the litter opening (188), and a control unit which is connected to the regulated conveying system (114) and is set up to output a control signal to the regulatable conveying system (114). Device (100) according to claim 1 , characterized in that the conveyor system (114) comprises a conveyor screw (156) which is set up to transport the pourable substance from the storage container (102) to the litter opening (188). Device (100) according to one of the preceding claims, characterized in that the conveyor system (114) has an adjustable drive (160) connected to the control unit. Device (100) according to one of the preceding claims, characterized in that the storage container (102) or the conveyor system (114) comprises a measuring unit which is set up to measure the quantity of the substances contained in the storage container (102) or from the storage container (102 ) taken pourable substance to determine. Device (100) according to claim 4 , characterized in that the measuring unit is a weighing unit which is set up to determine the mass of the pourable substance contained in the storage container (102). Device (100) according to one of Claims 4 or 5 , characterized in that the measuring unit is connected to the control unit and set up to output a measured variable to the control unit and that the control unit is set up to vary the control signal to the conveyor system (114) depending on the measured variable. Device (100) according to one of the preceding claims, characterized in that the storage container (102) comprises a stirring element (128) which is set up to keep the pourable substance contained in the storage container (102) in motion. Device (100) according to one of the preceding claims, characterized in that the mixing unit (104) comprises a pre-dissolution tank (180) with an inlet (190) for the treatment liquor, the inlet (190) being fluidically connectable to the inlet (106). and opens into the pre-dissolving tank (180) in such a way that the treatment liquor introduced into the pre-dissolving tank (180) via the inlet (190) circulates in the pre-dissolving tank (180). Device (100) according to claim 8 , characterized in that the sprinkling opening (188) is arranged over a section of the treatment liquor circulating in the pre-dissolving tank (180). Device (100) according to claim 8 or 9 , characterized in that the pre-dissolving tank (180) has a bottom outlet (198) and that the mixing unit (104) below the pre-dissolving tank (180) has an injection unit (200) which is fluidically connected to the outlet (198) of the pre-dissolving tank (180). connected is. Device (100) according to claim 10 , characterized in that the injection unit (200) has a removal volume (202) which is fluidically connected to the outlet (198) of the pre-dissolving container (180) and that in the removal volume (202) there is a volume connected to the inlet (106) of the mixing unit ( 104) fluidically connectable injector nozzle (206) is arranged, which is set up to generate a directed flow of the treatment liquor within the removal volume (202). Device (100) according to claim 11 , characterized in that the removal volume (202) is connected on the outlet side to the outlet (108) of the mixing unit (104). Device (100) according to one of the preceding claims, characterized in that the device (100) has a liquid container (220) for a liquid to be added to the dye liquor and a supply line fluidically connecting the liquid container (220) to the mixing unit (104) into which a liquid dosing device is switched on. Textile treatment plant for the treatment, in particular dyeing, of textile substrates with a device (100) according to one of Claims 1 until 13 and with a wet treatment tank for receiving and treating the textile substrate, wherein the wet treatment tank can be connected to the inlet (106) and the outlet (108) of the mixing unit (104) in order to transfer the treatment liquor into the wet treatment tank. textile treatment plant Claim 14 , characterized in that the control unit is part of a programmable control of the textile treatment plant. Use of a device (100) according to one of Claims 1 until 13 in a textile treatment plant for adding one or more pourable substances to an aqueous treatment liquor for the treatment of a textile substrate. use after Claim 16 , characterized in that the pourable substance is selected from the group of organic and inorganic salts. Textile treatment process in which at least one pourable substance is metered in a controlled manner into an aqueous treatment liquor circulating in a circuit of a textile treatment plant for the treatment, in particular dyeing, of a textile substrate.

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