DE202011050131U1 - Compact flotation - Google Patents

Abstract

Flotation tank (236), the flotation tank (236) being designed such that waste water (102) in the flotation tank (236) can be cleaned by means of flotation (114), so that a flotate (113) floats and clear water (104) is formed; a) wherein the flotation tank (236) has a first overflow (240), via which the clear water (104) can be guided out of the flotation tank (236); and b) wherein the flotation tank (236) has a second overflow (410), via which the flotate (113) can be passed out of the flotation tank (236); characterized in that c) that the first overflow (240) and / or the second overflow (410) is adjustable in height.

Description

Field of the invention

The invention relates to plants for the purification of wastewater by means of flotation.

Flotation plants are used to treat waste water from ingredients, d. H. of dispersed and / or emulsified substances, but also of suspended solids. There are different types of flotation. In addition to pressure-release flotation, induced-air flotation (AIF), electroflotation and microflotation are known.

Common to all flotation is the production of gas bubbles, which are introduced into the wastewater. By adherence of the bubbles to the dispersed materials, for example due to surface tension or due to electrostatic bonding of the bubbles to the dispersed materials and / or by trapping and incorporation of gas bubbles into the structure of flock dressings, d. H. Agglomerates of solids, float the dispersed substances and can be separated from the wastewater.

State of the art

The flotation processes and corresponding plants, called flotation plants, are familiar to the person skilled in the art. For example, the VDMA standard sheet " VDMA 24430 "Hints for the planning, design and execution of flotation systems for pressure-release flotation.

The publication EP 082 809 B1 describes the deposition of impurities by means of pressure release flotation. Wastewater mixed with air bubbles is introduced via an inner tube acting as a calming part into an outer tube designed as a flotation tank. In the outer tube, flotate rises. Clear water rises above an attached in the lower part of the outer pipe drain line. The end of the drain line is enveloped by a reservoir. Clear water, which flows from the drain pipe into the sump, is discharged via a spout attached to the bottom of the sump.

Such an arrangement has the consequence that the water level in the outer tube corresponds to the height of the drain line.

task

The object of the invention is to be able to flexibly adapt a flotation plant to wastewaters with various impurities, so that a flotation performance which meets the requirements is ensured throughout. The installation space required by the system should be reduced to a minimum.

solution

This object is achieved by the invention with the features of the independent claim. Advantageous developments of the invention are characterized in the subclaims. The wording of all claims is hereby incorporated by reference into the content of this specification. The invention also includes all reasonable and in particular all mentioned combinations of independent and / or dependent claims.

The invention relates to a flotation container, d. H. a container which is designed such that wastewater, in particular wastewater treated by chemicals, can be purified in the container by means of flotation, preferably by means of pressure-release flotation. As a result of the flotation, the substances to be separated from the wastewater float as a flotate. This produces clear water.

The flotation tank has a first and a second overflow. Overflow is generally understood to mean a partition wall with an overflow edge. It separates a first area in which a first fabric is located from a second area in which a second fabric is located. The first substance is flowable, such. As water or an air-flake-water mixture (flotate). The second substance is a gas, e.g. For example, air. As the level of the first fabric increases to the overflow edge, the first fabric flows over the overflow edge from the first region to the second region.

The first or lower overflow separates a part of the flotation tank in which the clear water is located from a part of the flotation tank in which air is located. Thus, the first overflow can direct a first part of the clear water from the flotation tank.

Analogously, the second overflow separates a first part of the flotation tank in which the flotate is located from a part of the flotation tank in which air and partly overflowed flotate is located. Thus, the second overflow can direct the flotate out of the flotation tank.

The overflow edge of the first overflow determines the level of the water level in the flotation tank. The floater, which floats in the flotation tank, is located partly between the water level and the overflow edge of the second overflow.

In the area of the water level, ie immediately below and above the water level, the flotate is particularly humid. Towards the top, the water content of the flotate decreases. In order to guide the most dehydrated flotate out of the flotation tank, therefore, a large distance between the water level and the overflow edge of the second overflow is favorable. Depending on the flotation tendency of the substances to be separated from the wastewater, however, this can mean that the buoyancy of the flotate is no longer guaranteed. As a result, the functionality of the flotation tank would no longer exist. Depending on the contamination of the waste water, there is therefore a preferred distance between the water level and the overflow edge of the second overflow.

To adapt to the contamination of the wastewater, therefore, the first and / or the second overflow are height adjustable. That is, the overflow edge of the first and / or the second overflow can be adjusted in the vertical direction. The height of the first overflow and / or the second overflow also varies the distance from the water level to the overflow edge of the second overflow. The distance from the water level to the overflow edge of the second overflow is thus adjustable.

In a preferred embodiment of the invention, the flotation tank is part of a plant for the purification of wastewater.

This system preferably has a turbidity sensor, which is mounted in such a way that it can determine the turbidity of the clear water. The turbidity sensor is therefore mounted inside the flotation tank, preferably in a final control tank, so as to come into contact with the clear water. Suitable measures for classifying the turbidity of the clear water, such as the turbidity units, which relate to the dilution of the liquid formazine (including NTU), are known in the art.

In a preferred embodiment of the invention, the system comprises means for injecting at least one precipitant and / or flocculant into the wastewater. Other means that are part of the system, regulate the amount of injected precipitant and / or flocculant depending on the turbidity of the clear water determined by the turbidity sensor. The higher the turbidity of the clear water, that is, the higher the turbidity value measured by the turbidity sensor, the greater the amount of precipitant and / or flocculant injected. As precipitants are preferably iron or aluminum salts, such as. As FeCl ₃ or AlCl ₃ , are used. As flocculants, polymers are used.

Alternatively, the injection of the precipitant and / or flocculant can be proportionate to the amount of wastewater. If the volume flow of the wastewater changes, the amount of precipitant and / or flocculant injected per unit time is varied by the same factor. Prerequisite for this is a constant composition of the wastewater or a homogenization with a pre-separator and / or stacking container. The injection of the precipitant and / or flocculant depending on the turbidity of the clear water, however, allows for varying composition of the wastewater automatic adjustment of the system and thus a saving of chemicals.

In addition, the system preferably comprises means for injecting at least one neutralizing agent into the wastewater. Preferably, exactly one neutralizing agent is injected, optionally a second neutralizing agent can be added. As a neutralizing agent, depending on the pH of the wastewater to be purified, alkalis, z. As sodium hydroxide, and / or acids are used. In particular, it is possible to provide both a lye and an acid as a neutralizing agent. This allows adaptation to changing wastewater and various feed chemicals.

The at least one neutralizing agent reacts with the precipitant and the contents of the wastewater. It arise z. B. metal hydroxides. If iron or aluminum salts are used as precipitant, the at least one neutralizing agent reacts with the precipitating agent to aluminum hydroxide or iron hydroxide.

The metal hydroxides precipitate out as water-insoluble compounds - flakes. Such flakes consisting of metal hydroxides have the property of adsorbing or adsorbing particles which are dissolved or finely dispersed in the water. Disperse substances to be separated from the waste water are thus bound in the precipitating flakes. Due to the flotation occurring in the flotation continue to adhere to air bubbles on the flakes. As a result, the flocs float as a floater on the water surface.

At least one pH sensor is preferably arranged such that the pH sensor can determine the pH value of the wastewater after the injection of the at least one neutralizing agent. Further agents regulate the amount of the at least one injected neutralizing agent as a function of the pH value of the wastewater determined by the at least one pH sensor after the injection of the at least one neutralizing agent. In this case, a decreasing pH value leads to an increased injection of the at least one neutralizing agent. Analog becomes as the pH increases, the amount of injected at least one neutralizing agent is reduced.

It would also be possible to inject the at least one neutralizing agent as a function of the wastewater and to add the precipitant. However, to accommodate a varying composition of the effluent, injection of the at least one neutralizing agent is preferred depending on the pH of the effluent after injection of the at least one neutralizing agent.

Optionally, the pH of the clear water, such as in the final control tank, is controlled to control the means for injecting the at least one neutralizing agent into the wastewater as a function of this pH. For this purpose, the system may have at least one pH sensor, which is arranged such that it can determine and record the pH of the clear water.

The flakes which precipitate as a result of the reaction of the precipitating and / or flocculant and / or at least one neutralizing agent with the constituents of the wastewater are very fine. In a preferred embodiment of the invention, the system therefore comprises means for injecting a polymer, for. As polyacrylate, as flocculants in the wastewater. The polymer combines the fine flakes into flake agglomerates, i. H. to larger flakes.

Further agents control the amount of polymer injected as a function of turbidity of the clear water determined by the turbidity sensor. Excessive turbidity of the clear water suggests that the precipitated flakes are too small. This is countered by an increase in the amount of polymer injected. With less turbidity of the clear water, the amount of injected polymer can be reduced.

The plant preferably has a first container - a stack container - for temporarily storing the waste water and a first pump - a feed pump - for pumping out the waste water from the stack container. An activation of the feed pump takes place when the level of the waste water in the stacking container reaches a maximum. Before commissioning, the system is filled with fresh water or purified wastewater (clear water).

In order to eliminate solids when switching off the application after switching off the feed pump, the system has a purging function in a preferred embodiment. The purge function is realized by a liquid-conducting connection between an outlet of the feed pump and a Y-piece, by a second pump, by a liquid-conducting connection between the Y-piece and an inlet of the second pump, by a liquid-conducting connection between an outlet of the second pump and the flotation tank, through a check valve, through a liquid-conducting connection between the flotation tank and an inlet of the check valve, and through a fluid-conducting connection between the outlet of the check valve and the Y-piece. The liquid-conducting connection between the flotation tank and the inlet of the check valve is arranged on the flotation tank in such a way that it can guide a second part of the clear water out of the flotation tank.

Under a liquid-conducting compound is at least one plant component to understand, which is traversed by liquid - sewage or clear water. In particular, a plurality of such system components, which are connected in series, referred to as a liquid-conducting connection. A liquid-conducting connection may consist, for example, of pipelines, fittings, fittings, containers and pumps.

A pump generally has two connections. A first port through which fluid enters the pump is called an inlet. Similarly, a second port through which the fluid exits the pump is referred to as output. The pump thus delivers the liquid from its entrance to its exit.

Check valves are in a first flow direction - the passage direction - continuous and lock in a second flow direction - the reverse direction. Each of the ports of a check valve is referred to as an input and an outlet, wherein a liquid can flow in the passage direction through the inlet into the non-return valve and can flow out through the outlet from the non-return valve.

If the feed pump is active, the wastewater passes through the liquid-conducting connection between the outlet of the check valve and the Y-piece in the reverse direction in the check valve. Thus, the waste water does not pass through the liquid-conducting connection between the flotation tank and the inlet of the check valve into the flotation tank.

The second pump (process pump) is preferably self-priming. After emptying the stacker, the feed pump is deactivated. Now suck the second pump (process pump) through the liquid-conducting connection between the flotation tank and the input the check valve, by the liquid-conducting connection between the outlet of the check valve and the Y-piece, and by the liquid-conducting connection between the Y-piece and the input of the second pump, clear water from the flotation tank and promotes it through the liquid-conducting connection between the output of the second pump and the flotation tank back into the flotation tank.

Wastewater, which was previously in the liquid-conducting connection between the Y-piece and the inlet of the second pump, in the second pump, and in the liquid-conducting connection between the second pump and the flotation tank, is thus displaced from the clear water. That is, the liquid-conducting connection between the Y-piece and the inlet of the second pump, the second pump, and the liquid-conducting connection between the outlet of the second pump and the flotation tank are rinsed with clear water.

In addition to the means for injecting the at least one precipitant and / or flocculant and / or the at least one neutralizing agent into the wastewater, the plant preferably comprises means for generating fine gas or air bubbles in the wastewater.

After injection of the at least one precipitant and / or flocculant and / or at least one neutralizing agent into the wastewater, flakes pass for about one to two minutes as a result of the reaction of the at least one neutralizing agent with the precipitant and / or flocculant and the contents of the effluent fail. Therefore, it is necessary that the effluent after injection of the precipitant and / or flocculant and / or the at least one neutralizing agent remains in the plant for about one to two minutes before it enters the flotation tank.

This purpose is served by a reaction vessel. This is generally to be understood as a thickening in a pipeline. Preferably, the reaction vessel is in the form of a cylinder having a diameter that is significantly larger than the diameter of the pipeline. The disadvantage of such a solution is an increased space requirement.

In order to make the plant compact, therefore, in a preferred embodiment, it has a pipeline which is bent, so that the distance between the ends of the pipelines is less than the length of the pipeline. The length of the pipeline is to be understood here as the length of the curve formed by the centers of the line cross sections.

For example, the pipeline can be serpentine, meandering or spiral. It is also possible to adapt the bend of the pipeline to the available space. Preferably, at least two changes in the flow direction by 180 ° in each case or a change in the flow direction by at least 360 ° take place in the pipeline.

The pipeline is part of a liquid-conducting connection for introducing the waste water into the flotation tank. In this case, the pipeline is arranged such that the gas or air bubbles and the precipitant and / or flocculant and / or the at least one neutralizing agent can be passed through the pipeline. The pipeline thus serves to ensure an adequate residence time of the wastewater after the injection of the precipitant and / or flocculant and / or the at least one neutralizing agent before the wastewater enters the reaction vessel. Preferably, the residence time is 1-10 minutes or 3-5 minutes. The pipeline can replace the reaction vessel, but it can also be used in combination with it.

The small dimensions of the system allow the realization of a preferred embodiment with a frame, wherein all components of the system including the controller are fixed to the frame.

In a further preferred embodiment, the plant comprises means for injecting an antiplexing agent into the wastewater and / or means for injecting an organic splitter into the wastewater and / or means for injecting an oxidizing agent into the wastewater. Organosulfides, e.g. B. Trimercapto-s-triazine are suitable as anti-blocking agent. As an organic splitter, polyamides can be used. The oxidizing agent is, for example, hydrogen peroxide (H ₂ O ₂ ).

In addition to heavy metals complexing agents such as. As EDTA or NTA may be included. Since complexed heavy metals are water-soluble, they can not be precipitated as hydroxides. By means of the anti-plexing agent, the heavy metal complexes react to water-insoluble complexes or sulfides and can be precipitated.

Preferably, the injection of the antiplex agent is proportional to the amount depending on the flow rate of the wastewater. Depending on the amount and nature of the pollution load contained in the wastewater, an injection of 0.1 to 0.5 liters of the antiperspirant per cubic meter of wastewater.

The organic breaker serves to break up stable emulsions, such as coolants or drilling fluid emulsions.

The oxidizing agent causes oxidation of organic and inorganic compounds. Purpose of the injection of the oxidizing agent is it, possibly occurring odor nuisance, z. B. by hydrogen sulfide (H ₂ S) to eliminate.

• – Einleiten des Abwassers in den Flotationsbehälter;
• – Reinigen des Abwassers in dem Flotationsbehälter mittels Flotation, sodass ein Flotat aufschwimmt und Klarwasser entsteht;
• – Leiten eines ersten Teils des Klarwassers und/oder des Flotats über mindestens einen Überlauf aus dem Flotationsbehälter heraus; und
• – Variieren der Höhe des mindestens einen Überlaufs.

The process which can be carried out by means of a flotation container according to the invention or a system for purifying wastewater which has such a flotation container comprises all or parts of the following steps:

• - introducing the waste water into the flotation tank;
• - Flotation of the waste water in the flotation tank so that a flotate floats and clear water is produced;
• - Passing a first part of the clear water and / or the flotate via at least one overflow from the flotation tank out; and
• - varying the height of the at least one overflow.

• – Ermittlung der Trübung des Klarwassers;
• – Injektion mindestens eines Fällungs- und/oder Flockungsmittels in das Abwasser und Regeln der Menge des injizierten Fällungs- und/oder Flockungsmittels in Abhängigkeit von der Trübung des Klarwassers;
• – Injektion eines Polymers in das Abwasser und Regeln der Menge des injizierten Polymers in Abhängigkeit von der Trübung des Klarwassers;
• – Injektion mindestens eines Neutralisationsmittels in das Abwasser, Ermitteln des pH-Werts des Abwassers nach der Injektion des mindestens einen Neutralisationsmittels und Regeln der Menge des injizierten mindestens einen Neutralisationsmittels in Abhängigkeit vom pH-Wert des Abwassers nach der Injektion des mindestens einen Neutralisationsmittels;
• – vor Außerbetriebnahme der Anlege: Leiten eines zweiten Teils des Klarwassers aus dem Flotationsbehälter heraus, Spülen der Anlage mit dem zweiten Teil des Klarwassers (Spülbetrieb), wobei der zweite Teil des Klarwassers anstelle des Abwassers in den Flotationsbehälter eingeleitet wird (interne Kreislaufführung);
• – Injektion eines Antiplexmittels in das Abwasser; Injektion eines organischen Spalters in das Abwasser; und/oder Injektion eines Oxidationsmittels in das Abwasser.

Preferably, the method may also comprise the following steps:

• - determination of the turbidity of the clear water;
• - Injecting at least one precipitant and / or flocculant into the wastewater and controlling the amount of the injected precipitant and / or flocculant depending on the turbidity of the clear water;
• Injection of a polymer into the wastewater and control of the amount of injected polymer as a function of the turbidity of the clear water;
• Injecting at least one neutralizing agent into the effluent, determining the pH of the effluent after the injection of the at least one neutralizing agent and controlling the amount of the injected at least one neutralizing agent as a function of the pH of the effluent after the injection of the at least one neutralizing agent;
• - before putting the unit out of operation: passing a second part of the clear water out of the flotation tank, flushing the unit with the second part of the clear water (flushing operation), the second part of the clear water being introduced instead of the waste water into the flotation tank (internal circulation);
• - Injection of an antiperspirant into the wastewater; Injecting an organic splitter into the waste water; and / or injecting an oxidizing agent into the wastewater.

The steps do not have to be performed all and not necessarily in the order given, and the method to be described may also have other steps, not mentioned.

Further details and features will become apparent from the following description of preferred embodiments in conjunction with the subclaims. In this case, the respective features can be implemented on their own or in combination with one another. The possibilities to solve the problem are not limited to the embodiments. For example, area information always includes all - not mentioned - intermediate values and all imaginable subintervals.

The embodiments are shown schematically in the figures. The same reference numerals in the individual figures designate the same or functionally identical or with respect to their functions corresponding elements. In detail shows:

1 a functional structure of a system according to the invention with rinsing function;

2a a flow diagram of a system according to the invention (full flow method);

2 B a flow chart of a system according to the invention (partial flow method);

3 a section of the flowchart;

4 a flotation tank in the supervision (full flow) and

5 a sectional view of the flotation tank (full flow method).

In the 1 illustrated functional structure illustrates the principle of a flotation plant with integrated flushing function. By mixing 100a of sewage 102 with a second part 104b a clear water 104 A mixture is created 106a , The proportion of wastewater 102 and the second part 104b of clear water 104 on the mixture 106a is variable. In regular operation of the plant, the mixture exists 106a exclusively from the wastewater 102 , By mixing 100b of the mixture 106a from the sewage 102 and the second part 104b of clear water 104 and air 110 , a mixture is formed 106b in which the air 110 contained in the form of fine bubbles. There is a separation 112 into a flotation 113 and the clear water 104 , The mixing 100b and the disconnect 112 be considered flotation 114 designated. By sharing 116 becomes the clear water 104 in a first part 104a and the second part 104b divided. The proportion of the first part 104a and the second part 104b on the clear water 104 is variable. In regular operation of the plant is all clear water 104 when first part 104a dissipated. To flush the system, the proportion of the second part 104b on the clear water 104 elevated. At the same time, the proportion of wastewater decreases 102 on the mixture 106a to zero. The mixture 106a now consists exclusively of the second part 104b of clear water 104 ,

In an embodiment of the invention according to 2a becomes the sewage 102 first in a pre-separator 202 initiated. In the pre-separator 202 Float light liquids such as oil and grease and can be separated. Sedimentable particles in the wastewater 102 are contained, settle at the bottom of the pre-separator 202 from. The execution of the pre-separator 202 can according to the standards DIN 1999-100 . DIN 1999-101 . DIN EN 858-1 and DIN EN 858-2 or DIN EN 1825 respectively.

From the pre-separator 202 flows pre-clarified wastewater 102 in a stack container 204 , The stack container 204 serves the intermediate storage and equalization of pre-treated wastewater 102 , In the stack container 204 there is a feed pump 206 , This promotes the wastewater from the stack container 204 , A check valve 208a prevents the sewage when switching off the feed pump 206 back into the stack container 204 flows.

A first level switch 210a and a second level switch 210b control the water level of the wastewater 102 in the stack container 204 , The first level switch 210a signals a minimum level. Once in the stack container 204 contained wastewater 102 falls below the minimum level, the first level switch switches 210a the feed pump 206 out. Exceeds the analog in the stack container 204 contained wastewater 102 a higher level, the second level switch switches 210b the feed pump 206 one. A third level switch 210c serves to trigger an alarm when the level of the in the stack container 204 contained wastewater 102 has exceeded a maximum value.

The feed pump 206 conveys the wastewater via a first metering point 212a to a second pump - the process pump 214 , By means of a cock 216a can before the first dosing 212a Samples of the wastewater 102 be removed.

At the first metering point 212a There are either one, two or three containers with an oxidizing agent 218 , an organic splitter 220 , or an antiperspirant 222 , dosing 224a . 224b and 224c inject the oxidant 218 , the organic splitter 220 and the antiplex agent 222 at the first metering point 212a into the sewage 102 , In this case, the amount of injected oxidant 218 , the injected organic splitter 220 and the injected antiplex agent 222 depending on the type of wastewater 102 be varied. In particular, it is possible to use only one or two of the three substances mentioned 218 . 220 and 222 to inject.

The attachment 224 works on the principle of pressure-release flotation. This is air 110 in the form of compressed air in the wastewater 102 initiated. Alternatively, a Venturi tube is suitable for injecting ambient air into the wastewater 102 , That with the air 110 staggered wastewater 102 enters the process pump 214 , The moving parts inside the process pump 214 swirl the sewage 102 with the air 110 and thus ensure a finer mixing.

Between the process pump 214 and the nozzle 226 it will be with the air 110 mixed wastewater 102 subjected to a pressure of 2 to 10 bar. As a result, the law of Henry Dalton releases the air 110 in the sewage 102 ,

Behind the relaxation nozzle 226 , which may be designed as a diaphragm, causes a reduction in the wastewater 102 prevailing pressure outgassing in the sewage 102 dissolved air 110 in the form of fine micro air bubbles.

After the relaxation nozzle 226 becomes the sewage 102 at a second metering point 212b passing in a reaction vessel 228 directed. Before the second metering point 212b there is a container with a precipitant and / or flocculant 230 , a container with an acid 231 as a neutralizing agent and / or a container with a base or alkali 232 as a neutralizing agent. dosing 224d . 224e and 224f serve to the precipitant and / or flocculant 230 , the acid 231 and / or the base or alkali 232 into the sewage 102 to inject.

In the reaction vessel 228 the precipitant and / or flocculant react 230 , the acid 231 and / or the base or alkali 232 , The resulting metal hydroxides precipitate as flakes. This is where the resulting gas bubbles adhere. In the reaction tank 228 To be able to better observe processes that take place is the reaction vessel 228 preferably made of a transparent material.

The wastewater 102 with the flakes and the air bubbles adhering to it is connected to a first pH sensor 234a and at a third metering point 212c over into the flotation tank 236 directed. Depending on the means of the first pH sensor 234a measured pH will be the injection of the acid 231 through the dosing pump 224e or the base or alkali 232 through the dosing pump 224f into the sewage 102 regulated.

Before the third metering point 212c there is a container with a polymer 238 , A dosing pump 224g serves to the polymer 238 into the sewage 102 to inject.

Due to the adherent and trapped air bubbles, the flocs float in the flotation tank 236 as a flotate 113 on. In the lower part of the flotation tank 236 As a result, clear water is formed 104 , The first part 104a of clear water 104 flows over a first overflow 240 from the flotation tank 236 , The first part 104a of clear water 104 can be used for further use or derived in a channel. A cock 216b allows sampling of the first part 104a of clear water 104 ,

By means of a sewer valve 242 may be the outflow of the first part 104a of clear water 104 be prevented. As a result, the water level 104 in the flotation tank 236 increases. An emergency overflow 244 in this case, it serves excess clear water 104 back into the stack container 204 to lead.

The flotation tank 236 has a first outlet 246a for clear water 104 on. From the first outlet 246a can clear water through a check valve 208b to a Y-piece 248 flow. The Y-piece 248 connects the feed pump 206 , the process pump 214 and the flotation tank 236 together. As a result, a rinsing function is realized. When the stack container 204 empties, so that a minimum level is exceeded, disabled the level switch 210a the feed pump 206 , As a result, the process pump sucks 214 over the first outlet 246a clear water 104 from the flotation tank 236 and flushes the pipes with it 258c . 258d and 258f , the reaction vessel 228 , the first pH sensor 243a and the riser 408 , In the further course, the metering pumps 224a . 224b . 224c . 224d . 224e and 224g off. To avoid sludge formation, the dosing pump remains 224g but initially active for a while.

During operation, on the other hand, the feed pump acts 206 in the reverse direction on the check valve 208b , By the from the feed pump 206 generated pressure, the check valve remains 208b closed. This prevents the sewage 102 through the first outlet 246a in the flotation tank 236 can penetrate.

A turbidity sensor 250 is like that on the final control container 251 attached that the turbidity sensor 250 the turbidity of the final control container 251 located clear water 104 can measure. Depending on this, the dosing pump 224d containing the precipitant and / or flocculant 230 into the sewage 102 injected, and the dosing pump 224g containing the polymer 238 into the sewage 102 injected, controlled.

Furthermore, a second pH sensor is optional 234b so at the final control container 251 attached that second pH sensor 234b the pH of the within the flotation tank 236 located clear water 104 can measure. The second pH sensor 234b the pH serves as final check of the clear water 104 ,

To prevent the system from restarting 224 polluted clear water 104 can escape, first remains the channel valve 242 for a certain time, about 3-5 minutes, closed (start-up operation). The clear water 104 will then be over the emergency overflow 244 back into the stack container 204 guided. Once the by means of the first pH sensor 234a , the second pH sensor 234b , and / or the turbidity sensor 250 measured values meet the requirements, the channel valve 242 open, leaving the clear water 104 over the first overflow 240 from the plant 226 can drain away.

For emptying the flotation tank 236 and thus also the final inspection container 251 for cleaning work in the stacking container 204 points the flotation tank 236 a second outlet 246b on. The second outlet 246b is about a cock 216c with the stack container 204 connected. After opening the tap 216c this flows into the flotation tank 236 contained clear water 104 and flotate 113 back into the stack container 204 ,

Similarly, the reaction vessel 228 be emptied. Such is the reaction vessel 228 about a cock 216d with the stack container 204 connected.

Optional is the flotation tank 236 with a muddy cleaner 252 fitted. The muddy cleaner 252 has moving parts, the flotate 113 can remove mechanically.

About a process 254 the flotate arrives 113 from the flotation tank 236 and gets into an optional existing sludge dewatering tank 256 directed. The sludge dewatering tank 256 separates the flotate 113 by filtration of clear water contained therein. By opening a tap 216e This filtrate can be returned to the pre-separator 202 be directed. If there is too much flotate 113 in the sludge dewatering tank 256 , triggers a fourth level switch 210d , of the over the sludge dewatering tank 256 is appropriate, an alarm off. In this case, the system turns off 224 out. Optionally, the flotate 113 also directly into the pre-separator 202 be routed and separated there.

• – eine Rohrleitung 258a zwischen dem Vorabscheider 202 und dem Stapelbehälter 204,
• – eine Rohrleitung 258b zwischen dem Stapelbehälter 204 und dem Y-Stück 248,
• – eine Rohrleitung 258c zwischen dem Y-Stück 248 und der Prozesspumpe 214,
• – eine Rohrleitung 258d zwischen der Entspannungsdüse 226 und dem Reaktionsbehälter 228,
• – eine Rohrleitung 258e zwischen dem Reaktionsbehälter 228 und dem Stapelbehälter 204,
• – eine Rohrleitung 258f zwischen dem Reaktionsbehälter 228 und dem Flotationsbehälter 236,
• – eine Rohrleitung 258g zwischen dem ersten Überlauf 240 und einem Kanal oder einem Brauchwassertank,
• – eine Rohrleitung 258h zwischen dem Notüberlauf 244 und dem Stapelbehälter 204,
• – eine Rohrleitung 258i zwischen dem zweiten Auslass 246b für Klarwasser 104 und dem Stapelbehälter 204,
• – eine Rohrleitung 258j zwischen dem ersten Auslass 246a für Klarwasser 104 und dem Y-Stück 248,
• – eine Rohrleitung 258k zwischen dem Ablauf 254 und dem Schlammentwässerungsbehälter 256, und
• – eine Rohrleitung 258l zwischen dem Schlammentwässerungsbehälter 256 und dem Vorabscheider 202.

The attachment 224 includes the following pipelines:

• - a pipeline 258a between the pre-separator 202 and the stack container 204 .
• - a pipeline 258b between the stack container 204 and the Y-piece 248 .
• - a pipeline 258c between the Y-piece 248 and the process pump 214 .
• - a pipeline 258d between the relaxation nozzle 226 and the reaction vessel 228 .
• - a pipeline 258E between the reaction vessel 228 and the stack container 204 .
• - a pipeline 258f between the reaction vessel 228 and the flotation tank 236 .
• - a pipeline 258g between the first overflow 240 and a canal or a hot water tank,
• - a pipeline 258h between the emergency overflow 244 and the stack container 204 .
• - a pipeline 258i between the second outlet 246b for clear water 104 and the stack container 204 .
• - a pipeline 258j between the first outlet 246a for clear water 104 and the Y-piece 248 .
• - a pipeline 258K between the expiration 254 and the sludge dewatering tank 256 , and
• - a pipeline 258l between the sludge dewatering tank 256 and the pre-separator 202 ,

The rooster 216a is at the pipeline 258E appropriate. Furthermore, the first metering point 212a Part of the pipeline 258E , The second metering point 212b is part of the pipeline 258d , The rooster 216d opens and closes the pipeline 258E , Part of the pipeline 258j is the check valve 208b , The pipeline 258i gets from the tap 216c closed and opened. The channel valve 242 opens and closes the pipeline 258g , Furthermore, the cock 216b on the pipeline 258g appropriate. The rooster 216e opens and closes the pipeline 258l ,

The check valve 208a forms together with the pipeline 258b a liquid-conducting connection between the feed pump 206 and the Y-piece 248 , A fluid-conducting connection between the Y-piece 248 and the input of the process pump 214 exists in the form of the pipeline 258E , The pressure increase stage 260 , the relaxation nozzle 226 , the pipeline 258d , the reaction vessel 228 and the pipeline 258f form a fluid-conducting connection between the output of the process pump 214 and the flotation tank 236 , Part of the pipe connection 258j forms a liquid-conducting connection between the flotation tank 236 and the entrance of the check valve 208b , Another part of the pipe connection 258j forms a liquid-conducting connection between the outlet of the check valve 208b and the Y-piece 248 , The pipeline 258b , the Y-piece 248 , the pipeline 258E , the process pump 214 , the pressure increase stage 260 , the relaxation nozzle 226 , the pipeline 258d , the reaction vessel 228 and the pipeline 258f form a liquid-conducting connection for introducing the wastewater 102 in the flotation tank 236 ,

In the 2a illustrated attachment 224 works according to the so-called full-flow method. The full-flow process is the entire wastewater 102 pressurized. This requires that wastewater 102 the process pump 214 happen. In the sewage 102 Contaminations can therefore lead to increased wear in the process pump 214 to lead.

This is avoided in the so-called partial flow method. 2 B represents a plant 224 which works by the partial flow method. It is constantly a third part of the clear water 104 from the flotation tank 236 returned, compressed, relaxed and with the from the stacking container 204 pumped wastewater 102 mixed. The air 110 will not be in the sewage 102 but in the returned, third part of the clear water 104 , Analog applied to the process pump 214 not the wastewater with the pressure, but the third part of the clear water 104 , The pressurized third part of the clear water 104 happens before mixing with the wastewater 102 the relaxation nozzle 226 ,

At the in 3 illustrated embodiment, the reaction vessel is missing 228 , Instead, the pipeline is 258d Meander-shaped, designed as a so-called loop reactor. This allows a particularly compact design of the system 224 , At the same time, the meandering design of the pipeline 258d a sufficient residence time of the wastewater before entering the flotation tank 236 guaranteed.

• – eine Flotationskammer 402 mit einem Steigrohr 408,
• – einen daran anschließenden Endkontrollbehälter 251 und
• – eine Flotatrinne 406, die konzentrisch um die Flotationskammer 402 herum verläuft und über eine Schräge zum Flotatablauf 254 führt.

The flotation tank 236 is in detail in 4 and 5 shown. As in 4 can be seen, is the flotation tank 236 divided into three sections

• - a flotation chamber 402 with a riser 408 .
• - An adjoining final control container 251 and
• - a flotatrinne 406 concentric around the flotation chamber 402 runs around and over a slope to Flotatablauf 254 leads.

Inside the flotation chamber 402 there is a riser 408 , Inside the final inspection container 251 are the height-adjustable first overflow 240 as well as the emergency overflow 244 arranged.

The operation of the flotation tank in the full flow process is in 5 seen. The treated wastewater 102 , with the flakes contained in it is over the riser 408 in the flotation tank 236 initiated. Due to the adhering air bubbles, the flocs float on the water surface and condense to form flotate 113 , The sidewalls of the flotation chamber 402 make up the second overflow 410 of the flotate. Flotat 113 that exceeds these sidewalls flows into the Flotatrinne 406 , The bottom of the Flotatrinne 406 owns a slope. This causes the flotate to flow 113 in the direction of the process 254 through which the flotate 113 from the flotation tank 236 in the sludge dewatering tank 256 arrives.

In the flotation chamber 402 is located below the floating flotate 113 clear water 104 , This is done by means of a passage 412 in the lower part of the flotation chamber 402 in the final control container 251 directed.

As soon as the level 414 of clear water 104 the first overflow 240 exceeds minimal, clear water flows 104 in the first overflow 240 and thus gets out of the flotation tank 236 out. In normal operation thus defines the height 416a the first overflow 240 the level 414 of clear water 104 ,

Only when the capacity of the first overflow 240 not enough, that the flotation tank 236 supplied clear water 104 dissipate, or if the channel valve 242 closed, the level exceeds 414 of clear water 104 the first overflow 240 , The height of the emergency overflow 244 exceeds the height 416a the first overflow 240 , Therefore, initially no clear water occurs 104 in the emergency overflow 244 , Only when the level 414 of clear water 104 the emergency overflow 244 slightly exceeds, the clear water flows 104 through the emergency overflow 244 from. To prevent the clear water 104 in the sludge dewatering tank 256 is the overflow edge of the second overflow 410 above the overflow edge of the emergency overflow 240 arranged, ie the height of the emergency overflow 240 is less than the height 416b the second (flotation) overflow 410 ,

Not shown in 5 the muddy-clearer 252 , the first outlet 246a for the clear water 104 , and the second outlet 246b for the clear water 104 ,

An essential parameter for the performance of the plant 224 is the difference 418 between the height 416b the second (flotation) overflow 410 and the height 416a the first (clear water) overflow 240 , This difference 418 correlates with the height of the floating flotate 113 , To regulate the difference 418 is therefore the first (clear water) overflow 240 height-adjustable.

This is the first overflow 240 from an upper pipe section 240a and a lower tube section 240b , The inner diameter of the upper pipe section 240a is equal to or minimally larger than the outer diameter of the lower pipe section 240b , This allows the upper tube section 240a to push or screw over the lower tube section.

It is intended that the clear water 104 over the upper edge of the upper pipe section 240a in the first overflow 240 flows. If necessary, the upper pipe section 240a by means of a seal against the lower pipe section 240b be sealed.

The upper pipe section 240a and the lower tube section 240b can be designed as threaded pipes, which are screwed together for the purpose of height adjustment. Alternatively, the upper pipe section 240a executed as a sliding sleeve. A rubber seal between the lower pipe section 240b and the upper pipe section 240a Prevents the upper pipe section 240a slip.

An alternative solution for regulating the difference 418 , is a height adjustable second overflow 410 , As a variation of the height of the sidewalls of the flotation chamber 402 difficult to realize, could be the second overflow 410 analogous to the first overflow 240 be designed as a tube located inside the flotation chamber 402 located. The Flotatrinne 406 would then be omitted.

LIST OF REFERENCE NUMBERS

100a

Mix

100b

Mix

102

sewage

104

clear water

104a

first part of the clear water

104b

second part of the clear water

106a

mixture

106b

mixture

110

air

112

Separate

113

Flotat

114

flotation

116

share

202

pre-separator

204

stacking containers

206

feed pump

208a

check valve

208b

check valve

210a

first level switch

210b

second level switch

210c

third level switch

210d

fourth level switch

212a

first metering point

212b

second metering point

212c

third metering point

214

process pump

216a

Sampling tap inlet

216b

Sampling tap drain

216c

Drain cock flotation tank 236

216d

Drain tap reaction tank 228

216e

Filtrate drainage sludge tank (optional)

218

Oxidizing agent (optional)

220

organic splitter (optional)

222

Antiperspirant (optional)

224

investment

224a

Dosing pump for the oxidizing agent 218

224b

Dosing pump for the organic splitter 220

224c

Dosing pump for the antiplex agent 222

224d

Dosing pump for the precipitant and flocculant 230

224e

Dosing pump for the acid neutralizing agent 231

224f

Dosing pump for the alkaline neutralizing agent 232

224g

Dosing pump for the flocculation aid (polymer) 238

226

expansion nozzle

228

reaction vessel

230

Precipitant and / or flocculant

231

acid

232

Base or alkali

234a

first pH sensor for pH control

234b

second pH sensor for final pH control

236

flotation

238

polymer

240

first (clear water) overflow

240a

Upper pipe section of the first overflow 240

240b

lower pipe section of the first overflow 240

242

channel valve

244

emergency overflow

246a

first outlet

246b

second outlet

248

Y-piece

250

turbidity sensor

251

Endkontrollbehälter

252

sludger

254

Flotate sequence

256

Sludge dewatering tank (optional)

258a

pipeline

258b

pipeline

258c

pipeline

258d

pipeline

258E

pipeline

258E

pipeline

258f

pipeline

258g

pipeline

258h

pipeline

258i

pipeline

258j

pipeline

258K

pipeline

258l

pipeline

260

Boost stage

402

flotation

406

Flotatrinne

408

riser

410

second (flotation) overflow

412

passage

414

Level of clear water or water level

416a

Height of the first (clear water) overflow

416b

Height of the second (flotation) overflow

418

Height difference

quoted literature

cited patent literature

• EP 082 809 B1

quoted non-patent literature

• VDMA 24430
• DIN 1999-100
• DIN 1999-101
• DIN EN 858-1
• DIN EN 858-2
• DIN EN 1825

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• EP 082809 B1 [0005]

Cited non-patent literature

• VDMA 24430 [0004]
• DIN 1999-100 [0060]
• DIN 1999-101 [0060]
• DIN EN 858-1 [0060]
• DIN EN 858-2 [0060]
• DIN EN 1825 [0060]

Claims (13)

Flotation tank ( 236 ), the flotation tank ( 236 ) is designed such that wastewater ( 102 ) in the flotation tank ( 236 ) by means of flotation ( 114 ), so that a flotate ( 113 ) floats and clear water ( 104 ) arises; a) the flotation tank ( 236 ) a first overflow ( 240 ) over which the clear water ( 104 ) from the flotation tank ( 236 ) can be directed; and b) the flotation tank ( 236 ) a second overflow ( 410 ), via which the flotate ( 113 ) from the flotation tank ( 236 ) can be directed; characterized in that c) that the first overflow ( 240 ) and / or the second overflow ( 410 ) is height adjustable. Investment ( 224 ) for cleaning wastewater ( 102 ), characterized by a flotation container ( 236 ) according to claim 1. Investment ( 224 ) according to the preceding claim, characterized in that a turbidity sensor ( 250 ) is mounted such that the turbidity sensor ( 250 ) the turbidity of the clear water ( 104 ) can determine. Investment ( 224 ) according to the preceding claim, characterized by a) means for injecting at least one precipitant and / or flocculant ( 230 ) into the wastewater ( 102 ); and b) means for controlling the amount of injected precipitant and / or flocculant ( 230 ) as a function of the turbidity sensor ( 250 ) determined turbidity of the clear water ( 104 ). Investment ( 224 ) according to the preceding claim, characterized by a) at least one agent for injecting at least one neutralizing agent ( 231 . 232 ) into the wastewater ( 102 ); b) at least one pH sensor ( 234b ), wherein the at least one pH sensor is arranged such that the pH sensor ( 234b ) the pH of the wastewater ( 102 ) after the injection of the at least one neutralizing agent ( 231 . 232 ) can determine; and by c) at least one means for controlling the amount of the injected at least one neutralizing agent ( 231 . 232 ) as a function of the pH of the wastewater determined by the at least one pH sensor ( 102 ) after the injection of the at least one neutralizing agent ( 231 . 232 ). Investment ( 224 ) according to claim 4, characterized by a) means for injecting at least one neutralizing agent ( 231 . 232 ) into the wastewater ( 102 ); and b) at least one pH sensor ( 234b ), wherein the at least one pH sensor is arranged such that the pH sensor ( 234b ) the pH of the clear water ( 104 ) can determine. Investment ( 224 ) according to claim 6, characterized by means for controlling the amount of the injected at least one neutralizing agent ( 231 . 232 ) depending on the pH of the clear water ( 104 ). Investment ( 224 ) according to one of claims 3 to 7, characterized by a) means for injecting a polymer ( 238 ) into the wastewater ( 102 ); and b) means for controlling the amount of injected polymer ( 238 ) as a function of the turbidity sensor ( 250 ) determined turbidity of the clear water ( 104 ). Investment ( 224 ) according to one of claims 2 to 8, characterized by a flushing device with: a) a first outlet 246a ; b) a check valve 208b ; and with c) a self-priming process pump 214 , Investment ( 224 ) according to one of claims 2 to 9, characterized by a) a first pump ( 206 ) for pumping out the waste water from the first container ( 102 ) for temporarily storing the wastewater ( 102 ); b) a liquid-conducting compound ( 208a . 258b ) between an output of the first pump ( 206 ) and a Y-piece ( 248 ); c) a second pump ( 214 ); d) a liquid-conducting compound ( 258c ) between the Y-piece and an input of the second pump ( 214 ); e) a liquid-conducting compound ( 226 . 260 . 258d . 228 . 258f ) between an output of the second pump ( 214 ) and the flotation tank ( 236 ); f) a check valve ( 208b ); g) a liquid-conducting connection between the flotation tank ( 236 ) and an input of the check valve ( 208b ), wherein the liquid-conducting connection between the flotation tank ( 236 ) and the inlet of the check valve ( 208b ) so on the flotation tank ( 236 ) that it is the clear water ( 104 ) from the flotation tank ( 236 ); and h) a liquid-conducting compound ( 258j ) between the outlet of the check valve ( 208b ) and the Y-piece ( 248 ). Investment ( 224 ) according to one of claims 2 to 10, characterized by a) means ( 226 . 260 . 214 ) for generating gas or air bubbles in the wastewater ( 102 ); b) means for injecting at least one precipitant and / or flocculant ( 230 ) and / or at least one neutralizing agent ( 231 . 232 ) into the wastewater ( 102 ); c) a liquid-conducting compound ( 258b . 248 . 258E . 214 . 260 . 226 . 258d . 228 . 258f ) for introducing the wastewater ( 102 ) into the flotation tank ( 236 ); d) a pipeline ( 258d ), whereby the pipeline ( 258d ) Part of the liquid-conducting compound ( 258b . 248 . 258E . 214 . 260 . 226 . 258d . 228 . 258f ) for introducing the wastewater ( 102 ) into the flotation tank ( 236 ) 214 e) where the pipeline ( 258d ) is arranged such that the gas or air bubbles and the at least one precipitant and / or flocculant ( 230 ) and / or the at least one neutralizing agent ( 231 . 232 ) through the pipeline ( 258d ), and f) where the pipeline ( 258d ) is bent so that the distance between the ends of the pipeline ( 258d ) is less than the length of the pipeline ( 258d ). Investment ( 224 ) according to one of claims 2 to 11, characterized by a frame, wherein all components of the plant ( 224 ) are fixed to the frame. Investment ( 224 ) according to any one of claims 2 to 12, characterized by a) means for injecting an antiperspirant agent ( 222 ) into the wastewater ( 102 ); and / or b) means for injecting an organic splitter ( 220 ) into the wastewater ( 102 ); and / or c) means for injecting an oxidizing agent ( 218 ) into the wastewater ( 102 ).

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