Chemical-energetic exhaust air scrubber

Abstract

The invention relates to an arrangement for the environmentally friendly purification of ammonia-containing exhaust air, particularly from livestock farms or food processing plants. A liquid with a pH value greater than 8 is introduced into the exhaust air in the form of droplets, wherein the liquid comprises a proportion of electroactivated water (10) of more than 60 wt.%. The electroactivated water (10) is generated by applying an electrical voltage using a membrane separation process, wherein the liquid contains sodium hypochlorite, with the proportion of sodium hypochlorite being less than 5 wt.% and more than 0.05 wt.%. The liquid contains magnesium chloride, with the proportion of magnesium chloride being less than 5 wt.% and more than 0.05 wt.%.

Description

[0001] The invention relates to an arrangement for the environmentally friendly purification of ammonia-containing exhaust air, in particular from animal fattening or food processing plants.

[0002] Ammonia (NH3) is a gaseous nitrogen compound and a precursor to air pollutants such as particulate matter. Ammonia emissions occur in all phases of manure management, with ammonia nitrogen from animal excrement being the main source. In barns, the ammonia evaporates from the manure, spreads throughout the building, and is eventually discharged through the ventilation system.

[0003] The exhaust air volume flows from forced-ventilation animal housing are characterized by daily and seasonal changes in the outdoor climate, animal density, animal size, and animal activity. The composition of the housing exhaust air depends on the housing, ventilation, and feeding methods, as well as general housing management. Accordingly, the required air flow rates in fattening systems range between approximately 8 and 100 m³ under winter and summer conditions. 3 / (TP h). Exhaust air temperatures are typically between 15 °C and 30 °C, and relative humidity fluctuates between 20 and 80%. Due to the relatively high air flow rates, the exhaust air contains only comparatively low concentrations of air pollutants. The odor concentration varies between 100 and 2,500 odor units per m², depending on the husbandry method. 3 . For total dust, the values ​​are in the range of 0.5 - 10 mg / m 3According to the Animal Welfare and Livestock Keeping Ordinance, ammonia concentration of 20 ppm must not be exceeded in the animal habitat, thus determining the raw gas concentration in the exhaust air to be filtered. In addition, the exhaust air contains other trace gases such as carbon dioxide, hydrogen sulfide, methane, and others. Trace gas concentrations in the raw gas can rise significantly with underfloor ventilation, heavily contaminated slatted floors, and the use of certain by-products as animal feed.

[0004] For efficient exhaust air purification, it is fundamentally important to ensure a homogeneous flow across the exchange surfaces through the structural design. Therefore, unnecessary air deflections, insufficient distances between fans and the first exchange surface (in forced air operation), excessively small pressure chambers in front of the first exchange surface, or the very uneven operation of the installed fans should be avoided. In suction operation, the fans are installed downstream of the exhaust air purification system. In this case, in addition to ensuring sufficient distance from the last exchange surface, particular attention must be paid to the use of corrosion-resistant fans. Incorrect operation can result in the release of corrosive gases and aerosols from the exhaust air purification system and damage to the fans.

[0005] Biofilters, single-stage biological trickle-bed filters, and multi-stage filters are predominantly used in fattening systems to remove odorous substances, dust, and ammonia, while chemical scrubbers are used to remove dust and ammonia. In all of these processes, the exhaust air constituents pass from the gas phase to the water phase on the moistened exchange surfaces.

[0006] In biofilters, the biofilter material, which must be kept moist throughout, represents the exchange surface. In trickling-bed filters, this function is performed by the sprinkled packing material and the water droplets forming in the system. Insufficiently moistened exchange surfaces cause raw gas breakthroughs and lead to a deterioration in the separation efficiency. If the exchange surfaces dry out, mass transfer at these points in all systems comes to a complete standstill.

[0007] The mass transfer of water-soluble exhaust air constituents (e.g., ammonia) can be increased by increasing the exchange surface and by achieving the largest possible concentration difference between the gas and liquid phases. Since an increase in the ammonia concentration in the stable air is not legally permissible, high mass transfer can only be achieved by keeping the ammonia concentration in the wash water as low as possible. In trickling bed filters or wash stages operated solely with water, the ammonia concentration in the wash water rises rapidly, and the concentration gradient decreases until the concentration equilibrium is reached. However, the concentration gradient can be maintained if the dissolved ammonia is chemically bound (chemical scrubbers) or biologically converted by microorganisms (biofilters, biologically operating trickling bed filters, and wash stages). The dissolution of ammonia increases the pH value in the wash water.During nitrification, which occurs in biological systems, the ammonium is oxidized to nitrite and then to nitrate, which leads to a decreasing pH value.

[0008] With optimal nitrification, the resulting acidification of the wash water exceeds the alkaline effect of the ammonia dissolving into the solution, significantly lowering the pH and impairing microbial activity. As a result, nitrogen oxides are released from the wash water, which leave the system unfiltered on the clean gas side and pollute the environment. Therefore, the pH must be raised by the controlled addition of alkali.

[0009] Since the dust contained in barn exhaust air often contributes to deposits and blockages in water distribution systems and filler material, a good pre-separation system is advisable. This should begin in the collection duct through which the exhaust air is fed into the exhaust air purification system. The flow velocity should therefore be low (maximum 3.5 m / s) so that the coarse dust settles in the collection duct. Insulating the collection duct is essential to prevent condensation of the moist barn air.

[0010] To prevent blockages on the exchange surfaces of the packings, modern exhaust air purification systems use devices to pre-spray the exhaust air before it enters the packing. The packings used should generally be dimensioned to be as blockage-resistant as possible and have a pore volume of more than 95%. If necessary, different packings can be combined. The separated dust, which initially has a low water content and is therefore not water-soluble, undergoes swelling. As it absorbs water, its mass and solubility increase. This swelling allows the dust to be at least partially biodegraded.

[0011] Bioaerosols, i.e. airborne particles of biological origin (bacteria, fungi, spores, cell components) are often bound to dust particles, so that effective dust separation is also expected to result in the separation of bioaerosols.

[0012] When planning exhaust air purification systems, the water law requirements for handling potentially water-polluting substances must generally be observed. This applies to the design of the exhaust air purification system itself, as well as the necessary storage of operating materials such as acids, alkalis, nitrification inhibitors, or additives, as well as the storage of the wash water.

[0013] DE 102 49 053 A1 describes a chemical device for reducing emissions through a scrubbing system to minimize environmental pollution. The chemical exhaust air scrubber described consists of a scrubbing section with swirling and a mixing system.

[0014] DE 41 12 982 C 2 describes a variant of a biological exhaust air scrubber for an animal stable, comprising several scrubber sections arranged in a cascade, in which fillers made of loose material or profiled plates are arranged. Above these fillers are water outlet nozzles and at least one exhaust air connection, and below these fillers are a water collection basin and, in turn, at least one exhaust air connection. These fillers can be wetted by the downwardly flowing water and through which the exhaust air flows, generating a pressure drop. In the scrubber section(s) through which the exhaust air flows first, the fillers are designed differently than in the section(s) through which the exhaust air flows later, to generate a lower pressure drop.

[0015] DE 692 29 246 T2 describes a method for treating exhaust air from a stable and for treating washing liquid, at least a part of which takes place in a manure collection space which is arranged below a parking space in a living area for the animals and communicates with this via a grid in the floor of the parking space, wherein the exhaust air from the living area is passed through a spray area for washing liquid which is located outside the parking space for the animals in order to clean the exhaust air with the washing liquid and to ventilate the washing liquid and to enrich it with oxygen, after which at least a part of the cleaned air is discharged to the outside and at least a part of the oxygen-enriched washing liquid is transported through the manure collection space.

[0016] The contribution of livestock farms to total ammonia emissions is significant due to the large number of animals.

[0017] According to various studies, the dust emitted from animal fattening facilities consists primarily of particles composed of skin flakes, feces, and feed residues. These are therefore bioaerosols of environmental relevance and can pose a health hazard if released in large quantities. Odor emissions are also an important issue in animal fattening. Furthermore, large amounts of ammonia emissions pose a problem for sensitive ecosystems such as moors, bodies of water, and forests. The associated high input of nitrogen fertilizers leads to eutrophication, which can negatively impact biodiversity. To limit the negative environmental impacts of animal husbandry facilities, the total expected ammonia emissions are considered when permitting construction projects. The more ammonia a facility releases, the greater the minimum distance to sensitive ecosystems that must be maintained.

[0018] For this reason, many countries have strict environmental regulations and laws limiting ammonia emissions from livestock farms. Farms that exceed these limits may face fines or operating restrictions. Compliance with these regulations is therefore crucial to avoid legal problems.

[0019] The object of the invention is to provide a system for purifying ammonia-containing exhaust air that achieves guideline-compliant exhaust air with minimal processing effort. The system is intended to break down the pollutants contained in the system into their elementary molecules and / or combine them into environmentally friendly groups of substances. When purifying the exhaust air using this system, the risk to employees, animals, and the environment is minimized. Furthermore, odor nuisance caused by high ammonia concentrations is eliminated. Existing exhaust air treatment systems should be able to be converted to the system for purifying ammonia-containing exhaust air with minimal processing effort.

[0020] In addition, the arrangement should comply with the new EU Directive 2016 / 2284 and the TA Luft.

[0021] This object is achieved according to the invention by an arrangement for purifying ammonia-containing exhaust air according to claim 1, a method, and a use according to the independent main claims. Preferred variants can be found in the subclaims, the description, the exemplary embodiments, and the drawings.

[0022] Exhaust air ducting in animal fattening facilities is a crucial aspect of operation, as it contributes to improving air quality, controlling odors, and protecting the health of animals and employees. The specific exhaust air ducting can vary depending on the animal species and the size of the facility. The inventive system for purifying ammonia-containing exhaust air can be advantageously adapted to the wide variety of different exhaust air ducts in order to comply with the specified limits.

[0023] Livestock facilities are equipped with ventilation systems that circulate the air within the barn to reduce moisture, gases, and odors. These systems often include fans, vents, and ducts. Exhaust ducts carry polluted air out of the animal barns and can be used to discharge it into the atmosphere or treat it in special odor control systems. Some livestock facilities use odor control systems to remove or reduce odors from the exhaust air. This can be achieved through chemical or biological processes.

[0024] In a particularly advantageous variant of the invention, the contaminated exhaust air stream is treated with a liquid containing more than 60% by weight of electroactivated water. The electroactivated water is generated by applying an electrical voltage using a membrane separation process.

[0025] Electroactivated water is a solution created by applying electrical energy to water to induce chemical changes in its composition. This process leads to the formation of various charged ions and radicals that can exhibit antimicrobial and disinfectant properties. A number of chemical reactions can occur during the electrolysis of water.

[0026] At the anode, the oxidation of water to oxygen (O2) and the formation of protons (H3O + ) takes place. This can lead to the formation of hypochlorite ions (OCl - ) in the presence of chloride ions (Cl - ) from the water. At the cathode, the reduction of water to hydrogen gas (H2) takes place with the formation of hydroxide ions (OH - ) in the solution.

[0027] The resulting electroactivated water contains a variety of active components, including hypochlorite ions, hydroxide ions, and hydrogen peroxide (H2O2). These components exhibit antimicrobial and disinfectant properties and can be used for cleaning and disinfection.

[0028] The composition and thus also the properties of the electroactivated water can be controlled by the choice of electrolysis cells, electrode materials, current, voltage and electrolysis conditions.

[0029] Electroactivated water, produced by applying an electrical voltage through a membrane separation process, is a special type of electroactivated water. This method uses a special electrolysis cell separated by a membrane to produce electroactivated solutions with specific properties.

[0030] The electrolysis cell used to produce the electroactivated water according to the invention is divided into two chambers separated by a membrane. This membrane is a semipermeable barrier that allows the flow of ions between the chambers. The two chambers of the electrolysis cell are filled with water. This can be distilled water or a low-conductivity aqueous solution. Electrodes are placed in each chamber, one in the cathode chamber and one in the anode chamber. These electrodes are connected to an external direct current voltage source. When the voltage is applied, the electrolysis process begins. Electric current flows through the electrodes, causing chemical reactions at the electrode surfaces and at the membrane. The membrane allows the transport of ions between the chambers.

[0031] Depending on the membrane and the substance concentration, ions such as hydroxide ions (OH - ) in the cathode chamber and hypochlorite ions (OCl - ) are formed in the anode chamber. During the electrolysis process, electroactivated solutions with different properties are created in the two chambers. For example, the electroactivated water produced in the anode chamber has antimicrobial properties, while the water produced in the cathode chamber can be alkaline.

[0032] The use of the membrane separation process allows for targeted control of the composition and properties of the electroactive solutions. The exact composition and effect of the resulting electroactive solutions depend on the electrolysis conditions and the choice of membrane.

[0033] The liquid contains sodium hypochlorite as a reactant for the ammonia in the exhaust air, with concentrations of less than 5% by weight and more than 0.05% by weight. Sodium hypochlorite (NaClO) is a chemical compound often used as an oxidizing agent.

[0034] Furthermore, the liquid contains a magnesium chloride content of less than 5% by weight and more than 0.05% by weight. Magnesium chloride has the ability to accelerate cellular activity. Magnesium, a key element in the generation of many enzymatic reactions at the cellular level, becomes very effective in fighting infections when combined with chloride.

[0035] Preferably, the loading of the exhaust air with the liquid in the arrangement is more than 0.1 mg / m 3 , preferably more than 0.25 mg / m 3 , especially more than 0.5 mg / m 3 and / or less than 2.5 mg / m 3 , preferably less than 5 mg / m 3, in particular less than 10 mg / m 3 .

[0036] The air loading refers to the amount or concentration of liquid used to adequately remove air pollutants.

[0037] Air pollution can be measured and monitored in a variety of ways to assess and ensure air quality compliance with legal limits and guidelines. Air quality indices and monitoring systems often collect data on various pollutants and particles, such as ammonia concentration, to provide information about air pollution.

[0038] The limit values ​​for ammonia in animal fattening facilities vary depending on the country, region, and animal species. The setting of limit values ​​serves to protect the air quality in the vicinity of animal fattening facilities and ensure the health of animals and humans. The European Union has issued directives to limit ammonia emissions from animal husbandry operations. These directives establish emission limits for ammonia and must be implemented in the EU member states. In Germany, there are no nationwide limit values ​​for ammonia in animal fattening facilities. The regulations vary depending on the federal state and animal species. As a rule, the limit values ​​are set to comply with the requirements of the Federal Immission Control Act (BImSchG), which regulates the protection of the environment from air pollution.

[0039] In order to comply with the specified limit values ​​even with increased levels of dust and ammonia, the selected loading of the washing liquid according to the invention can be significantly below the specified limit values ​​in order to be able to comply with the more ambitious limit values.

[0040] Another factor influencing compliance with the specified ammonia emission limits is, for example, the droplet size adjustment during exhaust air spraying. In one variant of the invention, the average droplet size (droplet size distribution) is more than 0.1 µm and less than 10 µm.

[0041] Droplets are small, liquid or liquid-like particles, typically spherical or droplet-shaped. They consist of tiny amounts of a liquid surrounded by a surrounding phase, often a gas or another liquid.

[0042] The droplet size distribution refers to the distribution of the sizes of liquid droplets in a liquid or aerosol. This distribution indicates how droplet sizes are distributed in a sample by indicating the number of droplets in different size ranges.

[0043] For example, by adjusting the droplet size, a very large and advantageous phase interface is realized, whereby the active substances come into contact quickly and almost completely with the immissions in order to convert them into their elemental components.

[0044] The invention comprises a sensor for detecting the ammonia concentration of the exhaust air.

[0045] A sensor is a technical device or apparatus used to detect physical, chemical, or biological properties or changes in its environment and convert them into electrical signals or other quantifiable information. For example, the dosage of fluid in the exhaust air stream can be regulated depending on air pollutants such as ammonia.

[0046] Chemical gas detectors, for example, are used for this purpose. These sensors use chemical reactions to detect ammonia molecules in the air. These sensors operate on the principle of ammonia oxidation at an electrode and generate an electrical signal proportional to the ammonia concentration. These sensors are sensitive and accurate.

[0047] Alternatively, detection can be achieved using non-dispersive infrared sensors. These sensors detect ammonia by measuring infrared absorption at a characteristic wavelength. The concentration is calculated based on the change in absorption. NDIR sensors are stable and require little maintenance.

[0048] Another alternative is semiconductor sensors. Semiconductor sensors change their electrical conductivity in the presence of ammonia.

[0049] In a particularly advantageous variant, the arrangement has a chamber in which the liquid is metered using a device.

[0050] A chamber is part of the exhaust air treatment system, into which the upflow from the exhaust air duct is directed. In this chamber, also called a reaction chamber, the chemical reaction of, for example, ammonia with the added liquid takes place, forming the reaction products water and nitrogen. The raw gas from the barn is directed horizontally into the chamber via an inlet side and leaves the barn as clean gas via an outlet side.

[0051] Preferably, the chamber has a volume of more than 0.1 m 3 and less than 500 m 3 and a cross-sectional area of ​​more than 0.1 m 2 and less than 6 m 2 has on.

[0052] In a particularly advantageous variant, the chamber has a volume of more than 0.1 m 3 and less than 60 m 3 and a cross-sectional area of ​​more than 0.1 m 2 and less than 1 m 2This variant generally allows for a more compact system design and thus saves space. For systems that require rapid responses to changes in exhaust air quality, a smaller chamber volume helps shorten response times. This is important to ensure compliance with emissions regulations and minimize environmental impact.

[0053] The change in cross-sectional area from duct to chamber reduces the flow velocity of the exhaust air toward the chamber. The exhaust air expands into the chamber and is first directed into the trickling elements. These are then sprayed with circulating water. Depending on the pollutant levels detected in the exhaust air stream, electroactivated water is added via a nozzle assembly. A germicide can be added optionally.

[0054] In exhaust air purification, trickle bed filters refer to a special type of filter material or carrier material used in exhaust air purification systems to remove contaminants from the exhaust air. This process is often referred to as trickle bed or trickle filter technology. In a trickle bed filter, the contaminated exhaust air is passed through a layer of trickle beds. These trickle beds are often small, solid materials such as spheres, shells, hollow bodies, or structured packings. As the exhaust air flows through the trickle bed, contaminants are removed by adsorption, absorption, or chemical reactions on the surface of the trickle beds.

[0055] The choice of trickle bed materials is tailored to the specific pollutants that need to be removed. These materials include activated carbon, zeolites, ceramics, or plastics. The inventive design of the trickle bed filters achieves high purification efficiency.

[0056] Optionally, the exhaust air stream can be sprayed, also known as fogging, with electrically activated water in the exhaust air duct. Fogging occurs in the direction of the exhaust air flow. The spray angle of the fog nozzles is 85°.

[0057] For example, the nozzle assembly may have more than four nozzles and fewer than 200. The number can be adjusted to the exhaust air flow rate and the cross-section of the exhaust air duct. The spacing of the nozzles in the duct depends on the pressure and the beam angle. At a beam angle of 85°C, a distance of 50 cm should not be exceeded.

[0058] In one embodiment of the invention, the device has a rectangular, polygonal, hexagonal, trapezoidal, or triangular cross-sectional shape. In a particularly advantageous variant, the fogging device is circular.

[0059] In a variant of the invention, the device comprises a container in which the liquid is collected.

[0060] According to the invention, the container material reflects electromagnetic radiation in the range from 380 to 1700 nm. Reflection refers to the rebounding of waves at an interface where the wave impedance or refractive index of the propagation medium changes.

[0061] The angle of reflection corresponds exactly to the angle of incidence and both angles lie in the same plane as the normal.

[0062] Furthermore, the container has an insulation thickness of more than 10 cm, preferably more than 15 cm, in particular more than 20 cm with a U-value of less than 0.35. The U-value indicates the heat flow through a component depending on the temperature gradient between the warm and cold sides in the unit W / (m 2·K). The unit describes the energy flowing through per square meter in Kelvin.

[0063] Heat-resistant materials can withstand high temperatures for extended periods without losing their structural integrity, mechanical properties, or other essential characteristics. This allows the container used to maintain a constant temperature over a 24-hour period.

[0064] Thanks to its UV stability and thermal insulation, the container can withstand even the most extreme outdoor weather conditions. The container ensures that high temperatures can be maintained even on frosty nights.

[0065] For example, the recirculating water is collected in a storage tank. In addition to the recirculating water, the electroactivated water that has come into contact with the exhaust air stream is also collected in the storage tank. It is withdrawn from this storage tank in phases as wastewater to the external slurry tank in order to keep the concentration of exhaust gas constituents in the recirculating water at a specified maximum value. Fresh water is also added to ensure a constant water level in the storage tank.

[0066] In a further chamber design, the storage tank for the circulating water and trickle body is followed by another storage tank containing fresh water and a trickle body for sanitization using a germ remover. Water is drawn from this storage tank in phases as wastewater to the slurry tank to keep the germ concentration at a specified maximum. Fresh water is also added to ensure a constant water level in the storage tank.

[0067] The purified exhaust air, also called clean gas, leaves the chamber horizontally after treatment with the electroactivated water and optionally sanitization.

[0068] Preferably, the device comprises a high-pressure pump for metering the liquid in droplet form. The pressure range is from a minimum of 10 bar to a maximum of 50 bar.

[0069] For example, at a pressure of 15 bar, 49 ml of electroactivated water per minute is injected into the exhaust air stream.

[0070] Preferably, the exhaust air has a volume flow of more than 1 m 3 / h and less than 500,000 m 3 / h through the chamber.

[0071] In a particularly advantageous variant, an exhaust air volume flow of 10 m 3 / h up to 100 m 3 / h. Within these limits, the described device achieves a particularly high level of efficiency.

[0072] Establishing flow rates within specific limits contributes to process stability. Fluctuations in flow rates lead to undesirable process changes and quality problems. Adhering to minimum and maximum flow rates is crucial for plant safety, efficiency, and performance. Establishing a maximum flow rate helps ensure that the required reaction or processing times are met to achieve the desired product quality / removal rate of air pollutants. Furthermore, adhering to the minimum and maximum flow rates helps optimize the consumption of raw materials and operating resources such as water, chemicals, and energy, and contributes to the sustainability and economic efficiency of the process.

[0073] In addition, maintaining minimum and maximum flow rates will optimize the load on system components such as pumps, valves, and piping. This helps extend the service life of the equipment and reduce maintenance costs.

[0074] In a particularly advantageous variant of the invention, the exhaust air has a residence time in the chamber of more than 5 seconds and less than 20 seconds.

[0075] The minimum residence time ensures that the exhaust air has sufficient time to come into contact with the electroactivated water. A residence time that is too short results in not all pollutants being removed, which impairs the efficiency of the exhaust air treatment.

[0076] The maximum residence time ensures that the cleaned air leaves the exhaust air treatment system within a reasonable, predetermined time.

[0077] The actual volume flow and the residence time of the exhaust air in the chamber depend on the respective pollutant concentration detected in the raw gas / exhaust air stream. This varies depending on the occupancy density in the barn, the time of year, and other parameters.

[0078] According to the invention, the ammonia-containing exhaust air is purified by adding a liquid to the exhaust air in the form of droplets, wherein the liquid comprises a proportion of electroactivated water of more than 60 wt.%. The electroactivated water is generated by applying an electrical voltage using a membrane separation process. The liquid has a proportion of sodium hypochlorite of less than 5 wt.% and more than 0.05 wt.%. Furthermore, the liquid contains a proportion of magnesium chloride of less than 5 wt.% and more than 0.05 wt.%.

[0079] According to the invention, the system for the environmentally friendly purification of ammonia-containing exhaust air is used, in particular, to purify the exhaust air from animal husbandry or food processing plants. Efficient exhaust air purification from animal husbandry or food processing plants protects the health of employees and animals and prevents odor nuisance caused by ammonia. This is particularly relevant in plants located near residential areas. Furthermore, effective exhaust air purification ensures that plants meet their legal requirements.

[0080] In addition to the purification of ammonia-containing exhaust air in animal fattening or food processing plants, the arrangement can be used in slaughterhouses and slaughterhouses, oil processing, electroplating plants and in areas with high requirements for exhaust air purification, such as the aerospace industry (ultra-clean area).

[0081] Further features and advantages of the invention will become apparent from the description of embodiments with reference to drawings and from the drawings themselves.

[0082] It shows: Fig. 1 Cross section of the exhaust air duct with nozzles, Fig. 2 Longitudinal section through the exhaust air duct, Fig. 3 a cross-sectional view through the chamber. List of reference symbols 1 exhaust air duct 2 nozzle head 3 spray angles 4 Exhaust air inlet 5 Exhaust air outlet 6 nozzle unit 7th chamber 8 containers 9 High pressure pump 10 Electroactive water 11 Wastewater 12 Fresh water 13 trickling bodies 14 trickling particles using germ remover

[0083] In Fig. Figure 1 shows a cross-section through the exhaust air duct 1 with nozzle heads 2. In the illustrated design, four nozzle heads 2 are installed. The nozzle heads 2 spray washing fluid in the form of electroactive water with a spray angle 3 of 85°. The spraying occurs in the direction of the exhaust air flow. This angle can vary depending on the application. The nozzle head 2 has a 3 mm bore through which the washing fluid exits the nozzle head 2 into the exhaust air duct 1. For example, at a pressure of 15 bar, 49 ml of washing fluid per minute are injected into the exhaust air flow.

[0084] The Fig. The longitudinal section through an exhaust air duct 1 shown in Figure 2 has a plurality of nozzle heads 2 along the exhaust air duct. The exhaust air 4 enters the exhaust air duct 1 through extraction from the emission source and is guided horizontally to the outlet 5 into a chamber 7. In the example shown, an exhaust air duct has four nozzle units 6 at defined intervals, with each nozzle unit 6 consisting of four nozzle heads 2. The spacing and the number of nozzle heads 2 are adapted to the pollutant content in the exhaust air volume flow.

[0085] In Fig.Figure 3 shows a variant embodiment in a sectional view through the chamber 7. The device comprises a tank 8 with a high-pressure pump 9, in which the liquid is collected. For example, the circulating water is collected in a tank 8. In addition to the circulating water, the electroactivated water 10 that has come into contact with the exhaust air stream is also collected in the tank 8. It is withdrawn in phases from this tank as wastewater 11 to the external slurry tank in order to keep the concentration of exhaust gas constituents in the circulating water at a predetermined maximum value. Furthermore, fresh water 12 is added to ensure a constant water level in the tank 8. The exhaust air stream is directed over the trickling bodies 13, where it is sprinkled with electroactive water 10 and wash water from the tank 8 and then knocked off.

[0086] In a further embodiment of the chamber, the tank 8 for the circulating water and trickle body 13 is followed by another tank 8 containing fresh water 12 and a trickle body 14 for sanitization using a germ remover on the trickle body 14. Wastewater 11 is continuously drawn from this tank 8 to the slurry tank to maintain the germ concentration at a predetermined maximum level. Furthermore, fresh water 12 is added to ensure a constant water level in the tank 8.

[0087] The purified exhaust air 5, also called clean gas, leaves the chamber 7 after treatment with the electroactivated water 10 and optionally the hygienization by the germ remover on a trickling body 14 in a horizontal direction. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This 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

[0000] DE 102 49 053 A1

[0013] DE 41 12 982

[0014] DE 692 29 246 T2

[0015] EP 2016 / 2284

[0020]

Claims

[1] Regulation on the environmentally friendly purification of ammonia-containing exhaust air, particularly in animal fattening or food establishments, characterized by that a liquid with a pH value of greater than 8 is supplied to the exhaust air in the form of droplets, wherein the liquid comprises a proportion of electroactivated water (10) of more than 60 wt.%, wherein the electroactivated water (10) was produced by applying an electrical voltage by means of a membrane separation process, wherein the liquid comprises sodium hypochlorite and the proportion of sodium hypochlorite is less than 5 wt.% and more than 0.05 wt.%, wherein the liquid comprises magnesium chloride and the proportion of magnesium chloride is less than 5 wt.% and more than 0.05 wt.%. [2] Arrangement according to claim 1, characterized by that the load of the exhaust air with the liquid is more than 0.5 mg / m 3 and less than 10 mg / m 3 amounts. [3] Arrangement according to claim 1 or 2, characterized by that the average droplet size is more than 0.1 µm and less than 10 µm. [4] Arrangement according to one of claims 1 to 3, characterized by that the device has a sensor for detecting the ammonia concentration of the exhaust air. [5] Arrangement according to one of claims 1 to 4, characterized by that the arrangement has a chamber (7) in which the liquid is metered by means of a device. [6] Arrangement according to claim 5, characterized by that the chamber (7) has a volume of more than 0.1 m 3 and less than 500 m 3 has. [7] Arrangement according to claim 5 or 6, characterized by that the chamber (7) has a cross-sectional area of ​​more than 0.1 m 2 and less than 6 m 2 has. [8] Arrangement according to one of claims 5 to 7, characterized by that the device has more than 3 nozzles (6) and less than 200 nozzles (6). [9] Arrangement according to one of claims 5 to 8, characterized by that the device is designed depending on the geometry of the cross-section. [10] Arrangement according to one of claims 5 to 9, characterized by that the device has a reflective and insulating container (8) for the liquid. [11] Arrangement according to one of claims 5 to 10, characterized by that the device has a high-pressure pump (9) for dosing the liquid in the form of droplets. [12] Arrangement according to one of claims 5 to 11, characterized by that the exhaust air with a volume flow of more than 1 m 3 / h and less than 500,000 m 3 / h through the chamber (7). [13] Arrangement according to one of claims 5 to 12, characterized by that the exhaust air has a residence time in the chamber (7) of more than 5 seconds and less than 20 seconds. [14] Method for cleaning ammonia-containing exhaust air, in particular with an arrangement according to one of claims 1 to 13, with the following steps: - Supply of a liquid to the exhaust air in the form of droplets, - wherein the liquid comprises a proportion of electroactivated water (10) of more than 60% by weight, - wherein the electroactivated water (10) is produced by applying an electrical voltage by means of a membrane separation process, - wherein the liquid contains sodium hypochlorite and the proportion of sodium hypochlorite is less than 5% by weight and more than 0.05% by weight, - wherein the liquid contains magnesium chloride and the proportion of magnesium chloride is less than 5% by weight and more than 0.05% by weight. [15] Use of an arrangement according to one of claims 1 to 13 for cleaning exhaust air in animal husbandry or the food industry.

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