DE102022117723A1 - Adding dosing agent to the bottom of a sewer - Google Patents

Abstract

There is a method for introducing dosing agent, which preferably acts bactericidal or as an oxygen donor, into the wastewater 3 flowing in a sewer 1 at the channel bottom 6. This means that the dosing agent, which is used to control the bacterial activities in the wastewater to avoid the formation of hydrogen sulfide, introduced directly into the flowing wastewater 3. The resulting increase in efficiency can be increased even further if the dosing agent is introduced via several dosing points 11, which are distributed over a transverse direction 4 of the sewer 1, since then the amount of dosing agent to be introduced depends on the flow velocity and thus on the spatially resolved volume flow Wastewater can occur. In addition, dosage can take place directly on the channel wall 12 in order to influence bacteria present in the drain skin 14. Preferred dosing agents are hydrogen peroxide and/or formic acid. The invention allows the dosing agent to be used more efficiently compared to known systems.

Description

The subject of the present invention is a method and a device for introducing dosing agent into a wastewater flowing in a sewer with a sewer floor. The dosing agents are used in particular to reduce hydrogen sulfide formed in the sewer.

Wastewater, especially dirty water, especially industrial and household wastewater, often contains feces, food residues and the like, which cause bacterial growth in the wastewater and the sewers in which the wastewater is carried. These bacteria are aerobic, facultative anaerobic or obligate anaerobic. This means that aerobic bacteria need oxygen to survive, while anaerobic bacteria do not need oxygen to survive. Facultative anaerobic bacteria tolerate oxygen and can therefore survive in the presence of oxygen, while obligate anaerobic bacteria are inhibited or even killed in the presence of oxygen.

It has been shown that anaerobic bacteria in particular produce hydrogen sulfide due to their metabolism, while aerobic bacteria do not produce hydrogen sulfide. It is therefore known to use dosing agents to shift the balance in the sewer towards aerobic bacteria and/or to kill bacteria in the sewer in order to reduce or avoid the formation of hydrogen sulphide. Well-known additives include calcium nitrate, which contains chemically bound oxygen that can be metabolized by bacteria when added to wastewater. Alternatively, it is known to use hydrogen peroxide for the direct conversion of hydrogen sulfide, for releasing oxygen and/or as a bactericide.

Until now, these dosing agents were added to the sump of the pumps through which the wastewater is pumped. This can result in an overdose of the dosing agent.

Proceeding from this, the present invention is based on the object of at least partially overcoming the disadvantages known from the prior art.

This task is solved with the features of the independent claims. Further advantageous embodiments of the invention are specified in the dependent claims. The features specified in the claims are specified and explained in more detail in the description, with further preferred embodiments of the invention being presented.

The method according to the invention for introducing dosing agent into a wastewater flowing in a sewer with a channel bottom is characterized in that the dosing agent is introduced into the wastewater flowing in the sewer at the bottom of the sewer.

Instead of dosing the dosing agent into the pump sump, it is dosed directly into the wastewater flowing in the sewer. Adding it at the bottom of the sewer means that the dosing agent is added under water and can mix directly with the wastewater. So it is added directly where the bacteria present there convert the dosing agent. In addition, the addition under water at the bottom of the channel enables the amount of dosing agent to be added per unit of time to be adjusted much more quickly than when added at another location, such as at the pump sump. In particular, overdosing based on the inertia of the methods known from the prior art, which is necessary to safely prevent hydrogen sulfide formation despite the inertia of the system, can be avoided and thus dosing agent can be saved.

By adding it to the channel floor, dosing agent is also made available to the channel floor. A high number of bacteria is to be expected on the canal floor due to the formation of a sewage membrane. The introduction at the channel bottom is preferred by at least one metering point formed in the channel bottom or by introducing metering points, for example on a metering arm that rests on the channel bottom.

Preferably, the wastewater flows through the sewer in one flow direction and the sewer has a transverse direction perpendicular to the flow direction, the dosing agent being introduced into the sewer at at least two dosing points on the bottom of the sewer, which are formed at different positions in the transverse direction. By introducing several dosing points on the channel floor, which have different positions in the transverse direction, different amounts of dosing agents can be added in the transverse direction. The amount of dosing agent can thus preferably be adapted to the volume flow of wastewater at the respective position. This enables a further reduction in the amount of dosing agent to be added, since it is thus possible to add amounts of dosing agent that are adjusted to the correct position. This also makes it possible, in particular, for large sewers, for example with a width or a diameter of min at least 800 mm [millimeters (DN800)], a uniform dosage across the width of the sewer that cannot be achieved with other methods.

The wastewater preferably flows in a flow direction through the sewer and the sewer has a transverse direction perpendicular to the flow direction, the wastewater having a velocity profile in the transverse direction, with metering agent being introduced into the sewer in the transverse direction in the region of a maximum of the velocity profile. The velocity profile can also be referred to as the flow profile and describes the location-dependent distribution of the flow velocity in the sewer depending on the transverse direction. At a particular position in the transverse direction, the wastewater still has a velocity distribution depending on the distance from the channel bottom at that particular position in the transverse direction, but this is of less importance for the further consideration of this invention. Here, to form the speed profile at a specific position, a representative speed for this position can be assumed, for example from the speed on the surface of the wastewater at this position or from an average speed at this position.

Depending on the flow conditions (e.g. laminar or turbulent), the velocity profiles have a maximum or a region of a maximum, for example a kind of plateau region in which the velocity is constant or changes only slightly, for example a region in which the velocity is at most 10% smaller is than the maximum, preferably at most 15% smaller than the maximum. Due to the high velocity of the wastewater in this area, there is also a correspondingly large volume flow, so that introducing dosing agent in this area is advantageous. In particular, if dosing agent is introduced at different dosing points in the transverse direction, a higher amount of dosing agent can be introduced in the area of the maximum in order to correspond to the higher consumption there due to the large volume flow. At the same time, less dosing agent can be added in other areas, so that a reduced amount of dosing agent can be added overall.

The amount of dosing agent introduced per unit of time is preferably determined depending on the velocity of the wastewater at the position where the dosing agent is added. The volume flow of wastewater is directly dependent on the speed of the wastewater. Consequently, the amount of bacteria to be treated - with the exception of the sewage membrane that forms on the canal walls and bottom - also depends on the velocity of the wastewater. Dosing depending on the velocity of the wastewater, preferably spatially resolved in the transverse direction, therefore enables dosing agent to be added to exactly the necessary extent, so that the amount of dosing agent to be added can be reduced.

The speed of the wastewater can be determined comparatively easily, for example indirectly by measuring the height or level of the wastewater in the sewer, which results in both an average flow speed of the wastewater and the speed profile under certain assumptions. The height measurement is carried out, for example, using ultrasonic sensors. Alternatively, direct measurement of the flow and thus the speed is possible, preferably with an ultrasonic sensor.

The wastewater preferably flows in a flow direction through the sewer and the sewer has a transverse direction perpendicular to the flow direction, with dosing agent being added in the transverse direction to at least one edge of the channel bottom. This enables the addition of dosing agent at the edge of the sewer floor and thus the sewer. Here the flow speed is regularly low due to the adhesion conditions on the canal wall, so that the bacteria in the wastewater flow only need a small dosage of dosing agent. However, there is a membrane on the canal wall that contains both dead and live bacteria, which can be influenced accordingly by adding the dosing agent to the canal wall.

The amount of dosing agent per unit of time that is added to the wastewater is preferably variable over time. This enables the dosage quantity to be adjusted very quickly to the conditions in the wastewater. By adding directly at the bottom of the channel, the process is practically inertia-free and allows the quantity supplied (actual quantity) to be immediately adjusted to the necessary quantity (target quantity).

The dosing agent is preferably introduced into the wastewater under pressure. In particular, in this case at least one nozzle can be used to introduce the dosing agent into the wastewater. The exit of the dosing agent under pressure advantageously reduces the risk that the dosing point will grow larger, i.e. that bacteria will accumulate at the dosing point and form a deposit there. It also allows you to admit under pressure In a simple way, by monitoring the pressure, the condition of the equipment used for adding the dosing agent can be monitored, since, for example, if one of the dosing hoses leaks or breaks, a pressure drop occurs that can be detected immediately. This means troubleshooting can be initiated immediately. Introducing dosing agent under pressure also reduces the risk of bacteria penetrating the dosing site. Furthermore, it is advantageous to rinse individual or all dosing points with a bactericidal agent such as hydrogen peroxide at predetermined times in order to kill and flush out any bacteria that may have penetrated.

At least one of the following compounds is preferably introduced into the wastewater as a dosing agent: calcium nitrate (Ca(NO ₃ ) ₂ ), hydrogen peroxide (H ₂ O ₂ ), acetic acid (C ₂ H ₄ O ₂ ), formic acid (CH ₂ O ₂ ), Ozone (O ₃ ), chlorine dioxide (ClO ₂ ), iron (II) chloride (FeCl ₂ ) and iron (III) chloride (FeCl ₃ ). Calcium nitrate is preferably added in an aqueous solution; it serves as an oxygen donor, so that the addition shifts the balance towards the aerobic bacteria. On the one hand, hydrogen peroxide has a bactericidal effect, i.e. reduces the overall bacterial load, and on the other hand, it serves as an oxygen donor. Hydrogen peroxide can advantageously be easily synthesized on site, so that the logistics for monitoring and refilling the dosing agent are significantly simplified here.

Acetic acid, like formic acid, has a bactericidal effect. Formic acid in particular can be produced locally using carbon dioxide. Ozone can be easily produced from atmospheric oxygen, for example using a corona discharge, and has both a bactericidal and oxygen donor effect. Chlorine dioxide has both a bactericidal and oxygen donor effect. Iron(II) chloride (FeCl ₂ ) and iron(III) chloride (FeCl ₃ ) have a different mechanism of action and do not directly affect the bacteria present. Rather, they cause the hydrogen sulfide to precipitate.

The use of hydrogen peroxide, ozonated water and/or formic acid as dosing agents is particularly preferred, since both substances are present as liquids or in aqueous solution and can therefore be easily dosed into the wastewater, especially under pressure. In addition, both dosing agents can be synthesized on site from regularly available substances (e.g. water, carbon dioxide) using, for example, electrical energy generated via photovoltaics, so that storage and logistics for the dosing agent can be eliminated. This significantly reduces both the personnel and financial costs for providing the dosing agent.

According to a further aspect of the invention, a device for introducing dosing agent into a wastewater flowing in a sewer with a channel floor is proposed, comprising at least one dosing arm, which includes at least one dosing opening for introducing dosing agent into the wastewater and can be positioned on the channel floor, a dosing agent source , which is in fluid communication with the at least one dosing opening, and a control device for controlling the amount of dosing agent dispensed through the dosing opening per unit of time, the control device, the dosing source and the at least one dosing opening being suitable and intended for carrying out the method according to one of the preceding claims are.

At least one metering opening preferably comprises a nozzle.

The details and advantages disclosed for the method, in particular with regard to determining the amount of dosing agent to be added and the type of addition, can be transferred to the device and vice versa.

• 1 ein erstes Beispiel eines Abwasserkanals im Querschnitt;
• 2 ein zweites Beispiel eines Abwasserkanals im Querschnitt;
• 3 ein erstes Beispiel einer Vorrichtung zum Einbringen eines Dosiermittels im Längsschnitt;
• 4 ein zweites Beispiel einer Vorrichtung zum Einbringen eines Dosiermittels im Querschnitt;
• 5 schematisch ein Beispiel einer Vorrichtung zum Einbringen eines Dosiermittels;
• 6 ein erstes Beispiel einer Dosiermittelquelle;
• 7 ein zweites Beispiel einer Dosiermittelquelle; und
• 8 eine bevorzugte Ausgestaltung einer Dosiermittelquelle.

The invention and the technical environment are explained in more detail below using the attached figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and findings from the present description and/or figures. The attached figures and in particular the proportions shown are only schematic. The same reference numbers designate the same objects, so that explanations from other figures can be used in addition if necessary. It shows schematically:

• 1 a first example of a sewer in cross section;
• 2 a second example of a sewer in cross section;
• 3 a first example of a device for introducing a dosing agent in a longitudinal section;
• 4 a second example of a device for introducing a dosing agent in cross section;
• 5 schematically an example of a device for introducing a dosing agent;
• 6 a first example of a dosing agent source;
• 7 a second example of a dosing agent source; and
• 8th a preferred embodiment of a dosing agent source.

1 shows a first example of a sewer 1 in cross section. The sewer 1 is flowed through by wastewater 3 in a flow direction 2, which points vertically into the image plane in the illustration. A transverse direction 4 runs perpendicular to the flow direction 2 and spans the width of the sewer 1. The wastewater 3 flows at a height 5 above a channel floor 6. The channel floor 6 is horizontal in the present example, the sewer 1 has a rectangular channel profile. Other channel profiles are possible, for example round or egg-shaped channel profiles, as well as channel profiles with a recess in the middle. Basically, the height 5 is defined in comparison to the lowest point of the channel profile at the measuring point.

1 also shows a speed profile 7 of the wastewater 3, which indicates the speed of the wastewater 3 in the direction of flow 2 depending on the position in the transverse direction 4 of the sewer 1. The speed profile 7 is shown as an example and in a highly stylized manner. It goes back to zero in the edge areas 10 and has a plateau area 8 centrally in the sewer 1. Depending on the flow conditions, this is also significantly narrower than here 1 shown as an example. The maximum 9 of the flow velocity is in the plateau area 8.

The wastewater 3 flows through the sewer 1, for example to a sewage treatment plant. The wastewater 3 includes, for example, domestic wastewater and in particular dirty water, which can also contain urine and/or feces in addition to water. The wastewater 3 and also the sewer 1 contain bacteria that can sometimes produce odorous substances such as hydrogen sulfide (H ₂ S). These are predominantly anaerobic bacteria that occur in balance with aerobic bacteria that convert oxygen. The addition of oxygen causes the balance to shift toward aerobic bacteria, reducing the formation of hydrogen sulfide. At the same time, hydrogen sulfide also has an indirect corrosive effect, since hydrogen sulfide can be converted bacterially into sulfuric acid, so that in addition to odor nuisance, significant corrosion of components of the sewage system such as the sewer itself but also pumps, valves or similar can occur if the hydrogen sulfide content in the system is too high Wastewater 3 is present. In addition, hydrogen sulfide is harmful to health.

In order to reduce the formation of hydrogen sulfide or to prevent it completely, dosing agents are added to the wastewater, which introduce oxygen into the wastewater 3 and/or which have a bacteriostatic or even bactericidal effect. Examples of such dosing agents are hydrogen peroxide, formic acid, acetic acid, chlorine dioxide, ozone and/or calcium nitrate. If hydrogen sulfide is already present in the wastewater, dosing agents can be added that cause the hydrogen sulfide to precipitate.

Until now, dosing agent was added in pump sumps or from above into the sewer. In contrast to this, it is proposed in the present case to meter in the dosing agent at the channel bottom 6. In the example below 1 This is done, for example, at four dosing points 11, which are distributed in the transverse direction 4 over the channel floor 6.

It is also possible to only provide one dosing point 11. However, all dosing points 11 are designed in such a way that the dosing agent is dosed at the channel bottom 6 into the wastewater 3 flowing in the sewer 1. The dosing points 11 can be integrated into the channel base 6, as shown here, or can also be formed on a dosing arm, as is the case 3 until 5 show.

The dosing points 11 in the present example are distributed in the transverse direction 4 over the sewer 1 so that two dosing points 11 are formed in the plateau area 8 of the velocity profile 7 and can thus add dosing agent into the area of the wastewater 3 in which it flows fastest. A dosing point 11 is formed in each edge region 10 of the speed profile 7, so that dosing agent can also be introduced into the slow edge region of the flow of wastewater 3.

A nozzle is preferably formed at the dosing points 11, which releases the dosing agent in the flow direction 2 of the wastewater 3. There is more information about this below with reference to 4 executed. The dosing agent is added under pressure. Alternatively, it is also possible to add the dosing agent without pressure. It is then preferred to provide only one dosing opening connected to a dosing agent source at the dosing points 11.

In the sewer 1 and there in particular on the sewer floor 6, as well as on the sewer walls 12, a sewage membrane, i.e. a biofilm, is created, which consists of dead and living biomass that contains bacteria and possibly still consists of inorganic components. By feeding directly to the channel bottom, the dosing agent is fed directly into the area of the sewer skin, so that the dosing agent is metered in directly where a large part of it is converted. The previously known dosing methods have the disadvantage that the dosing agent only insufficiently reaches the sewer membrane. Although this can achieve a reduction in hydrogen sulfide production in the water, the locally suboptimal supply of the dosing agent results in a significantly increased amount of dosing agent being supplied. The dosing process described here directly at the channel bottom can achieve an increase in the efficiency of hydrogen sulfide reduction, which enables a reduction in the consumption of dosing agent compared to conventional processes.

By distributing the dosing points 11 across the width of the sewer 1, it is possible to introduce different dosing agents locally in the transverse direction 4. Due to the significantly higher flow velocity in the plateau area 8 than in the edge area 10, the volume flow of wastewater 3 in the plateau area 8 is significantly larger than in the edge area 10. This enables a significantly higher addition of dosing agent in the plateau area 8 than in the edge area 10. The amount of dosing agent is advantageous , which is metered in, is determined depending on the speed of the wastewater 2 at the metering point 11. In the edge area 10, a larger amount of dosing agent is preferably added than results from the speed of the wastewater 3 in order to be able to specifically treat the drain skin on the respective sewer wall 12.

2 shows a second example of a sewer 1. Unless differences are explicitly pointed out, to avoid repetition, reference is made to the description of the first example in 1 referred. 2 shows schematically a second example with a different speed profile 7 with a smaller plateau area 10 and a corresponding dosage distribution 13 over the transverse direction 4 of the sewer 1. In 2 In the example shown, there are a large number of dosing points 11, which are provided with reference numbers only as an example. Each of these dosing points 11 releases a dosing amount 15 of dosing agent, which is in 2 marked by arrows. Continues to show 2 the drain skin 14 and the dosing quantities 15 per dosing point 11. The dosing distribution 13 is adapted to the speed profile 7, particularly in the plateau area 10, the amount of dosing agent 15 being increased at the edges of the sewer 1 in the transverse direction 4, in particular to the drain skin 14 and to be able to treat the bacteria present on the channel wall 12.

3 shows a first example of a device 16 for introducing dosing agent in cross section. In order to avoid repetitions, please refer to the comments 1 and 2 Referenced. In this example, the device 1 includes a retrofit solution in which, in contrast to the in 1 In the example shown, the dosing points 11 are not formed directly in the channel bottom 6, but rather in a dosing arm 17 as a dosing opening 18, which can be pivoted about a pivot axis 18 between a dosing position located on the channel bottom 6 (as shown) and a locking position in which the dosing arm 17 is parallel to is aligned with a fixing arm 19 fixed to the channel wall 12. In the dosing position, the dosing arm 17 rests on the channel floor 6. 3 shows only one half of the sewer 1, which is delimited by the sewer wall 12 on the one hand and a center line 20 on the other. The metering arm 17 is aligned obliquely in the flow direction 2, as is also the case in the second example of the device 16 in 4 is shown. In the second half of the sewer 1 lying on the other side of the center line 20, a further, in particular foldable, corresponding dosing arm 17 is formed.

4 shows a second example of a device 16 in a top view, with the dosing arm 17 also shown pivoted here in the dosing position. Only the differences to the first example will be highlighted here 3 otherwise, in order to avoid repetition, the above statements will be referred to 1 until 3 referred. In contrast to the first example, here the dosing arm 17 has three dosing points 11, while a fourth dosing point 11 is formed in the fixing arm 19 in order to be able to introduce dosing agent directly onto the channel wall 12. In contrast to the first example, the dosing points 11 are not designed as dosing openings, but rather as dosing nozzles 21. In this exemplary embodiment, the metering nozzles 21 are designed as flat nozzles which have a flattened jet cone 24. In this exemplary embodiment, the dosing nozzles 21 are each screwed into a stainless steel tube 22 which has a connection 23 through which the dosing nozzle 21 is connected to a dosing source (see 5 until 8th ) can be connected.

5 shows schematically an example of a device 16 for introducing dosing agent into wastewater 3 flowing in a sewer 1. The device 16 has eight dosing points 11, four of which are assigned to a dosing arm. The device 16 further comprises a dosing agent source 25, which is described in detail with reference to 6 and 7 is described in more detail. Two distributors 27 are fed with dosing agent via the dosing source 25 and the line system 26. Each distributor 27 has four dosing points 11 connected via adjusting means 28. The adjusting means 28 and the dosing source 25 are connected to a control device 30 via control lines 29, so that the control device 30 can control both the dosing source 25 and the dosing points 11 via the adjusting means 28 in order to introduce dosing agent through the dosing points 11 into the sewer Individual dosing points can be controlled in a time-variable manner.

Furthermore, the control device 30 can optionally be connected to a hydrogen sulfide sensor 31 and/or a height sensor 32 and/or a temperature sensor 33 via control lines 29. The hydrogen sulfide sensor 31 can be used to monitor the hydrogen sulfide concentration in the atmosphere in the sewer 1 or in the wastewater 3 and this hydrogen sulfide concentration can be taken into account when calculating the amount of dosing agent through the dosing points 11. The dosage quantity can be increased as the hydrogen sulphide concentration increases. The height 5 of the wastewater 3 in the sewer 1 is measured via the height sensor 32 (see above 1 and 2 ). The height sensor 32 preferably measures the height 5 using ultrasound measurements. Preferably, several height sensors 32 are formed, the signal of which is averaged. The flow velocity of the wastewater 2 results from the height 5. In addition, the velocity profile can also be deduced from the height 5. The temperature of the wastewater 3 and/or the atmosphere above the wastewater 3 is determined via the temperature sensor 33. The temperature has a strong influence on the proliferation of bacteria, so the dosage can be increased as the temperature increases.

6 shows a first example of a dosing agent source 25 for the pressureless addition of dosing agent, in particular via dosing openings 18. For this purpose, the dosing agent source 25 has a reservoir 34 in which the dosing agent is stored. The amount of dosing agent that flows from the reservoir 34 into the line system 26 can be controlled via an adjusting means 35, for example a valve. For this purpose, the adjusting means 35 is connected to the control device 30 via a control line 29.

7 shows a second example of a dosing agent source 25 for the addition of dosing agent under pressure, in particular via dosing nozzles 21. Here the reservoir 34 is connected to the line system 26 via a pump 36. The output power and/or the output pressure of the pump 36 can be controlled. For this purpose, the pump 36 is connected to the control device 30 via a control line 29.

8th shows a preferred embodiment of a dosing agent source 25, in which the reservoir 34 is supplied with dosing agent by a synthesizing unit 37. The dosing agent is produced in the synthesis unit 37. If the dosing agent is hydrogen peroxide, for example, hydrogen and oxygen can be produced from water in the synthesis unit 37 via electrolysis. The hydrogen peroxide can then be stored in the reservoir 34 as a dosing agent. The same applies to formic acid and acetic acid as dosing agents.

If ozone is used as the dosing agent, the synthesis unit 37 is designed as an ozone generator, for example via a non-thermal plasma. The ozone can then either - unlike shown in this figure - be added directly to the wastewater via the metering points 11, or introduced into water in the reservoir 34, which is then added to the wastewater 2 as ozonated water via the metering points 11.

The synthesizing unit 37 is in particular designed on site and generates the dosing agent from local resources, which includes, for example, water, for example collected rainwater or stored water, ambient air, waste heat from the wastewater and, for example, electrical energy generated via photovoltaic modules. This reduces operating costs because there is no need to stockpile the dosing agent and correspondingly monitor and fill the reservoirs 34 on site. The ones in the 5 until 8th The disclosed details of the dosing source 25 and the device 16 can also be combined in combination with dosing points 11 embedded in the channel bottom 6.

There is a method for introducing dosing agent, which preferably acts bactericidal or as an oxygen donor, into the wastewater 3 flowing in a sewer 1 at the channel bottom 6. This means that the dosing agent, which is used to control the bacterial activities in the wastewater to avoid the formation of hydrogen sulfide, introduced directly into the flowing wastewater 3. The resulting increase in efficiency can be increased even further if the dosing agent is introduced via several dosing points 11, which are distributed over a transverse direction 4 of the sewer 1, since the amount of dosing agent to be introduced then depends on the flow velocity and thus on the spatially resolved volume flow Wastewater can occur. In addition, dosage can take place directly on the channel wall 12 in order to influence bacteria present in the drain skin 14. Preferred dosing agents are hydrogen peroxide and/or formic acid. Through the Invention, the dosing agent can be used more efficiently compared to known systems.

Reference symbols

1

sewer

2

Direction of flow

3

sewage

4

Transverse direction

5

Height

6

Canal floor

7

Speed profile

8th

Plateau area

9

maximum

10

Edge area

11

Dosing point

12

Canal wall

13

Dosage quantity distribution

14

Sielhaut

15

dosage quantity

16

Device for introducing dosing agent

17

Dosing arm

18

Dosing opening

19

Fixing arm

20

Centerline

21

Dosing nozzle

22

Stainless steel tube

23

Connection

24

Beam cone

25

Dosage source

26

Piping system

27

Distributor

28

adjusting means

29

Control line

30

Control device

31

Hydrogen sulfide sensor

32

Altitude sensor

33

Temperature sensor

34

reservoir

35

adjusting means

36

pump

37

Synthesizing unit

Claims (10)

Method for introducing dosing agent into a wastewater (3) flowing in a sewer (1) with a channel bottom (6), characterized in that the dosing agent is introduced at the canal bottom (6) into the wastewater (3) flowing in the sewer (1). becomes. Procedure according to Claim 1 , in which the wastewater (3) flows through the sewer (1) in a flow direction (2) and the sewer (1) has a transverse direction (4) perpendicular to the flow direction (2), the dosing agent being used at at least two dosing points (11). is introduced into the sewer (1) on the channel bottom (6), which are formed at different positions in the transverse direction (4). Procedure according to Claim 1 or 2 , in which the wastewater (3) flows through the sewer (1) in a flow direction (2) and the sewer (1) has a transverse direction (4) perpendicular to the flow direction (2), the wastewater (3) flowing in the transverse direction (4 ) has a speed profile (7), with dosing agent being introduced into the sewer (1) in the transverse direction (4) in the region of a maximum of the speed profile (7). Method according to one of the preceding claims, in which the amount of dosing agent introduced per unit of time is determined depending on the velocity of the wastewater (3) at the position of addition of the dosing agent. Method according to one of the preceding claims, in which the wastewater (3) flows through the sewer (1) in a flow direction (2) and the sewer (1) has a transverse direction (4) perpendicular to the flow direction (2), in the transverse direction ( 4) dosing agent is added to at least one edge of the channel base (6). Method according to one of the preceding claims, in which the amount of dosing agent per unit of time added to the wastewater (3) is time-variable. Method according to one of the preceding claims, in which the dosing agent is introduced into the wastewater (3) under pressure. Method according to one of the preceding claims, in which at least one of the following compounds is added to the wastewater as the dosing agent is introduced: calcium nitrate (Ca(NO ₃ ) ₂ ), hydrogen peroxide (H ₂ O ₂ ), acetic acid (C ₂ H ₄ O ₂ ), formic acid (CH ₂ O ₂ ), ozone (O ₃ ), chlorine dioxide (ClO ₂ ) , iron(II) chloride (FeCl ₂ ) and iron(III) chloride (FeCl ₃ ). Device (16) for introducing dosing agent into a wastewater (3) flowing in a sewer (1) with a channel bottom (6), comprising at least one dosing arm (17) which has at least one dosing opening (18, 21) for introducing dosing agent into which comprises waste water (2) and can be positioned on the channel floor (6), a dosing agent source (25) which is in fluid communication with the at least one dosing opening (18, 21), and a control device (30) for controlling the flow through the dosing opening (18 , 21) dispensed amount of dosing agent per unit of time, the control device (30), the dosing source (25) and the at least one dosing opening (18, 21) being suitable and intended for carrying out the method according to one of the preceding claims. Device (16) after Claim 9 , in which at least one metering opening (18, 21) comprises a nozzle (21).

Images