RU2662529C2 - Method of municipal sewage treatment and technological complex for its implementation - Google Patents

Abstract

FIELD: municipal engineering.

SUBSTANCE: group of inventions refers to the treatment and disposal of municipal sewage and can be used in housing and communal services, as well as for cleaning industrial and agro-industrial waste water. Communal effluent is purified from nonspecific inclusions in the device in the form of screens, homogenized and alkalized with calcareous milk at a rate of 0.1–1.0 g/dm³ until a suspension with a pH of 10.5–11.5 is obtained. Suspension is further subjected to treatment with a complex of energy effects – cavitation, magnetostriction and ultrasound. Resulting suspension is treated with ozone for additional oxidation and the formation of water-insoluble salts, followed by their precipitation. Suspension is saturated with carbon dioxide until a pH corresponding to the MRL is obtained. Separation of the fractions is carried out gravitationally in a thin film filter to produce a thick precipitate and water. Water is further purified in fine post-treatment filters (10). Technological complex contains device for separating nonspecific inclusions (1), made in the form of screens, homogenizer for municipal wastewater (2), fecal pumps (3), faucet (4), device for preparing and dispensing a reagent (5), device for creating a cavitation process in a rotating magnetic field with ferromagnetic elements (6), ozone production and dosing unit (7), carbon dioxide storage and dosing unit (8), thin film filter (9), fine water aftertreatment filter (10).

EFFECT: group of inventions makes it possible to simplify the cleaning technology, increase the profitability of treatment facilities and significantly reduce the required areas without reducing the quality of cleaning, and also to provide flexible regulation of the complex's productivity and create environmentally safe working conditions, reducing the sanitary zone around the complex.

5 cl, 1 dwg, 1 tbl

Description

The group of inventions relates to methods for cleaning and disposal of municipal wastewater and can be used in housing and communal services, as well as for the treatment of industrial and agricultural wastewater, to obtain clean water that meets the MPC requirements and is acceptable for discharge into reservoirs of fishery or used as recycled water, as well as organic fertilizers for use in agriculture and landscaping services of settlements.

The prior art there are many options for methods and complexes for chemical treatment of water, mainly chlorine or chlorine-containing reagents, which leads to the formation of new compounds, often more dangerous than the original pollution. In addition, the chlorine industry itself is difficult and dangerous to maintain and maintain.

Known methods for cleaning municipal wastewater (for example, patents RU No. 2240984, 11/27/2004; RU No. 2258045, 08/10/2005; RU No. 35730, 02/10/2004), by filtering them through various filters that require constant washing and precipitation is formed, requiring utilization, which does not ensure water purification from impurities dissolved in it and disinfection of the source water.

The disadvantages of these methods are the need for large bodies of water, as well as the secondary pollution of treated effluents with microorganisms, the formation of large volumes of sludge, which requires disposal and is not suitable for direct use as organic fertilizers.

Known methods and devices for water purification by jet hydro-cavitation (RU No. 54662, 07/10/2006) and hydrodynamic treatment in a rotating magnetic field (RU No. 22328450, 07/10/2008).

The disadvantages of these technical solutions is the inability to provide a stable quality of cleaning and high performance.

A known installation for water purification by ozonation (RU No. 2228916, C02F 9/04, 05/20/2004), which contains an oxidation chamber (ozonation), and in the oxidation chamber there is a cavitator that provides a high degree of dispersion of water and its impurities, as a result what is the intensification of the oxidation of pollutants. Moreover, to ensure a high degree of purification, the gas-water mixture must be repeatedly circulated through the ejector and cavitator.

The disadvantage of this installation is the low productivity and complexity of maintenance, requiring appropriate staff qualifications.

The closest in technical essence and the achieved effect is the method of disinfection and purification of liquid media and the production line for its implementation (RU No. 2585635, C02F 9/12, 05.27.2016), which can be used for water treatment in drinking and industrial systems destination.

The method includes cavitation treatment of an aqueous medium with jet cavitation with ejection of air or an oxygen-air mixture into a cavitator, subsequent processing of the medium in a hydrodynamic reactor with a rotating magnetic field and ferromagnetic elements in the form of needles, sedimentation of the treated aqueous medium and separation of sludge. Cavitation treatment by jet cavitation in a hydrodynamic reactor is carried out with the formation of active oxidizing agents OH, H ₂ O ₂ and HO ₃ . Processing in a hydrodynamic reactor is carried out with the dispersion of particles to submicron sizes and increasing the gas-liquid-solid phase interface. Before cavitation treatment, the composition of the aqueous medium is averaged; during processing of the medium in a hydrodynamic reactor, at least one reagent selected from the group consisting of: milk of lime, aluminum sulfate, and ferric chloride is added to it. In addition, pulse processing of the obtained medium in a rotary-pulse apparatus and filtering of the medium using bulk filters are carried out, and the medium is ozonized and treated with ultraviolet light.

The production line contains a jet cavitator equipped with means for ejecting air or an oxygen-air mixture into it, a hydrodynamic reactor with a rotating magnetic field and ferromagnetic elements in the form of needles, and a sedimentation unit combined with a sludge removal system. The line additionally contains an averaging mixer installed in front of the jet cavitator, a reagent dispenser in a hydrodynamic reactor, and a medium sedimentation unit contains sedimentation hydrocyclones. The line additionally contains a rotary-pulse apparatus, bulk filters, a medium ozonation unit, and a medium ultraviolet treatment unit installed after the settling unit, as well as an automatic process control unit.

The disadvantages of the prototype presented are the rather high saturation of the line with expensive and sophisticated equipment that requires highly qualified service, the lack of modularity of construction, which ensures smooth smoothing of the instability of the flow of sewage during the day, and also does not allow for a smooth increase in the capacity of treatment plants without major overhauls.

The technical result achieved by this group of inventions:

- simplification of cleaning technology;

- increase the profitability of treatment facilities and a significant reduction in the required area without compromising the quality of treatment;

- providing flexible regulation of the performance of the complex, determined by the current flow;

- creating environmentally friendly working conditions and reducing the sanitary zone around the complex;

- the exclusion of large sedimentation tanks and silt fields.

The specified technical result for implementing the method of cleaning municipal wastewater is achieved by averaging the composition of the medium to be cleaned, alkalizing, treating with cavitation, a rotating magnetic field and ferromagnetic elements until a suspension is obtained, followed by its ozonation, filtration and separation of fractions; inclusions in the device in the form of sieves, homogenize and alkalize with milk of lime at the rate of 0.1-1.0 g / dm ³ to obtain a suspension with a pH of 10.5-11.5, then m this suspension is additionally subjected to a complex of energy influences - magnetostriction and ultrasound created in the energy-saturated field of the device, the resulting suspension is treated with ozone for additional oxidation and the formation of water-insoluble salts with their subsequent precipitation, then, to normalize the pH, the emulsion is saturated with carbon dioxide to obtain pH, corresponding to the MPC, and the separation of fractions is carried out gravitationally in a thin film filter to obtain a thick precipitate and water, which additionally purified in the filters of thin post-treatment.

The specified technical result for the technological complex of municipal wastewater treatment is achieved by the fact that, during the technological process, a mixer, a device for preparing and dosing a reagent in the form of lime milk, a device for creating a cavitation process in a rotating magnetic field with ferromagnetic elements and filters are installed, moreover, the complex is additionally equipped with a device for separating non-specific inclusions in the form of sieves, a homogenizer, with containing the functions of accumulation and homogenization, which is made in the form of an intermediate tank equipped with fecal pumps with cutting blades, a carbon dioxide suspension saturation unit, as well as a thin-film fraction separation filter and a fine filter, the mixer is made flow-through and a device for creating a cavitation process in a rotating a magnetic field with ferromagnetic elements is a process activation unit, made in the form of an electromagnetic device, also containing t sequentially located installation for the production and dosing of ozone, a storage device and a metered supply of carbon dioxide, while the outputs of the thick sludge from the thin film filter and one of the outputs of the fine filter are connected to a conveyor to separate the thick sludge into the accumulator, and the other output of the fine filter is connected to clean water discharge pipe. The mixer is made flowing and is a pipe with swirling flow blades. The thin-film filter is made in the form of a filter of gravitational separation of fractions and is a trough, with at least 20 parallel planes located at least 20 inclined at an angle of about 47 ° and made of a corrosion-resistant material, such as a polymer one with a slippery surface, alternating along the junction with the bottom of the trough . The fine filter is made in the form of a cartridge, for example, non-woven material.

The invention is illustrated in the structural diagram, where in FIG. 1 shows a production line of a municipal wastewater treatment complex, which contains sequentially installed device for separating nonspecific inclusions 1, made in the form of sieves, a drive-homogenizer of municipal wastewater 2, fecal pumps for bubbling communal wastewater 3 and feeding them to a flow mixer 4, a reagent preparation and metering device 5, installation of activation of processes 6, installation of production and dosing of ozone 7, device 8 for storage and dosed supply of CO ₂ , thin-film filter 9, filter p fine water purification 10, pits separation and transfer to the discharge of thick sediment 11.

In practice, the treatment of municipal wastewater is as follows.

Municipal wastewater purified from nonspecific contaminants is averaged in the device for separating nonspecific inclusions 1, then they are homogenized in a municipal wastewater homogenizer 2 by means of fecal sparging pumps 3. Then, the suspension obtained as a result of homogenization is sent to a flow mixer 4, where it is mixed with the reagent prepared in the preparation and dosing device of reagent 5, as a result, the suspension is alkalized, for example, with milk of lime.

Alkalization is carried out to a pH of 10.5-11.5 to obtain a large number of weak ions formed during the destruction in the energy-saturated field of the elements of lime milk CaO, Ca (OH) ₂ , which easily enter into metal hydroxide formation reactions requiring pH not lower than 8.5 , and inorganic water-insoluble salts formed from those destroyed during processing in an energy-saturated field of an installation for activation of processes of organic compounds, this process effectively occurs at pH 10.5-12.

The main executor of municipal wastewater treatment technology is a process activation unit 6, where, as a result of the action of shock waves generated in the energy-saturated field by the collapse of cavitation bubbles and ultrasound created by compressing cavitation bubbles and magnetostrictive phenomena of magnetic domains under the influence of a rotating electromagnetic field, this destroys all components of chemical and biological structures to the molecular level. As a result of the exposure, part of the water molecules is destroyed with the formation of atomic hydrogen H ⁺ and OH ^- ions, creating a redox environment that accordingly affects the cloud of free atoms and partially destroyed molecules. At the same time, the destruction of the entire microflora occurs, thereby completely sterilizing the communal runoff. As a result of the complex effect of the energy-saturated field, atoms and some partially destroyed molecules with open covalent bonds arise, striving to create new compounds according to the natural law of compounds with minimal electrical resistance, which are already environmentally friendly and easily absorbed by the soil-forming microflora and plant roots.

The energy saturation of the working area in the process activation unit and its qualitative characteristics, strength and the number of impacts on the medium being treated, are set not only by the electromagnetic field strength acting in the installation, but also by force effects from magnetic domains. The larger and stronger the particles of pollutants entering the sewage being cleaned, the larger the domains are required, since the magnetostrictive effects from them are more powerful, but the qualitative characteristics of the formation of water-insoluble compounds are lower than when exposed to the environment of smaller domains with sufficient quantity. The above also applies to the treatment of runoff containing metal compounds, the destruction of the molecules of which requires a more powerful energy effect. No less influence on the choice of domain parameters is exerted by the percentage of pollutants in the treated effluent. For a more complete process of formation of new environmentally friendly molecular compounds, high-quality mixing of the formed cloud of free radicals, which appeared in the working area of the plant, as a result of the destruction of the molecular compounds of pollutants, which requires a more “soft” but frequent exposure to the elements of the cloud, is required. Thus, the selection and installation of magnetic domains is carried out based on the average characteristics of the communal runoff at a particular facility.

As a result of the formation of new molecular compounds, a suspension is created with the properties of emergency separation due to the temporary absence of an electrostatic layer in newly formed molecules.

For a better completion of the oxidation processes in the compounds of the resulting suspension with the formation of water-insoluble salts, it is additionally treated with ozone from the unit for production and dosing of ozone 7, at a rate of 0.1-0.3 mg / l.

To normalize the pH and transfer a number of metals to carbonates, which also precipitate, the suspension is additionally treated with carbon dioxide from the device 8 for storage and dosed supply of CO ₂ .

The resulting suspension is rapidly stratified due to the temporary absence of an electrostatic layer in newly formed molecules.

Next, the suspension is sent to a thin-film filter 9, which consists of 20 slippery surfaces inclined at an angle of about 47 °, alternating along the contact to the bottom of the filter. The calculation of the performance of a thin-film filter is made from the conditions for ensuring the speed of flowing through it of the emulsion to be cleaned not higher than 0.07 m / h. As the suspension flows along the surfaces of the thin-film filter, gravitational separation of the fractions into thick sediment and water occurs.

As a result, at the exit from the thin-film filter 9, the water is practically free of suspensions and enters the fine filter 10, for example, consisting of 25 layers of non-woven material, while metal salts remaining or newly formed in the treated water are removed.

The thick sediment separated in the thin-film filter 9 and partially in the fine filter 10, through collection pits and transfer to the discharge of thick sediment 11 enters the conveyor to discharge it to the drive.

In order to increase the energy efficiency of the proposed method for treating municipal wastewater, all components of the complex are located in descending levels to organize its gravity flow. The performance of the equipment is regulated by turning on or off the individual modules of the process activation units, in accordance with the really required performance of the complex.

The line can be equipped with an automatic control and process control system for all nodes of the technological complex.

The devices for the preparation of lime milk, ozone and carbon dioxide that are part of the technological complex are widely known and supplied by manufacturers.

As an example, the result of using a technological complex for wastewater treatment in the city of Neftegorsk in the Samara Region with a capacity of 6000 m ³ / day according to the technology described above is presented.

Table 1 presents the results of laboratory monitoring of indicators on the composition of water before and after the treatment of municipal wastewater, which shows that the proposed cleaning method provides complete neutralization and removal of polluting components.

Thus, the proposed method and technological complex allows to ensure the treatment of municipal wastewater with the necessary performance and energy efficiency by activating the processes in the process activation unit and thin-film filter with minimal use of reagents, the absence of microbiological treatment and the maximum possible use of the Earth's gravitational field. This increases the efficiency of treatment facilities, increases their profitability and environmental safety with the absence of large sedimentation tanks and silt fields. The speed of cleaning communal runoff is reduced to 10-15 minutes.

Thick sediment can be treated with soil-forming microorganisms, as a result, an environmentally friendly, highly effective organic fertilizer can be obtained.

Claims (5)

1. A method of cleaning municipal wastewater, which consists in averaging the composition of the medium to be cleaned, alkalizing, treating with cavitation, a rotating magnetic field with ferromagnetic elements to obtain a suspension, followed by its ozonation, filtering and separation of fractions, characterized in that the municipal wastewater is cleaned of non-specific inclusions in device as a sieve, homogenized and basified with milk of lime at the rate of 0.1-1.0 g / dm ³ to obtain a slurry having a pH of 10.5-11.5, and then this suspension was further podver They can be treated with a complex of energy influences - cavitation, magnetostriction and ultrasound created in the energy-saturated field of the process activation device, the resulting suspension is treated with ozone for additional oxidation and the formation of water-insoluble salts, followed by their precipitation, then the suspension is saturated with carbon dioxide to obtain a pH corresponding to MPC, and fraction separation is carried out gravitationally in a thin-film filter to obtain a thick precipitate and water, which is further purified in fine filters. 2. A technological complex for treating municipal wastewater, in which a mixer, a device for preparing and dosing a reagent in the form of milk of lime, a device for creating a cavitation process in a rotating magnetic field with ferromagnetic elements and filters are installed, connected with each other by means of transportation, characterized in that the complex is additionally equipped with a device for separating nonspecific inclusions in the form of sieves, a homogenizer, combining the functions of accumulation and homogenization, which is made in the form of an intermediate tank equipped with fecal pumps with cutting blades, a carbon dioxide suspension saturation unit, as well as a thin film fraction separation filter and a fine filter, the mixer is made flow-through, and a device for creating a cavitation process in a rotating magnetic field with ferromagnetic elements is an installation of the activation of processes, made in the form of an electromagnetic device, also contains sequentially located a production unit for the production and dosing of ozone, a device for storing and dosing carbon dioxide, the outputs of the thick sludge from the thin film filter and one of the outlets of the fine filter are connected to the conveyor to separate the thick sludge into the accumulator, and the other output of the fine filter is connected to the exhaust pipe pure water. 3. The technological complex according to claim 2, characterized in that the mixer is made flowing and is a pipe with blades swirling the flow. 4. The technological complex according to claim 2, characterized in that the thin-film filter is made in the form of a filter of gravitational separation of fractions and is a trough with at least 20 parallel planes arranged at an angle of about 47 ° and made of a corrosion-resistant material, for example polymer, with a slippery surface, alternating in contact with the bottom of the gutter. 5. The technological complex according to claim 2, characterized in that the fine filter is made in the form of a cartridge, for example, non-woven material.

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