RU2736050C1 - Installation for treatment of waste water, drainage and over-slime waters of industrial facilities and facilities for arrangement of production and consumption wastes - Google Patents

Abstract

FIELD: water treatment.SUBSTANCE: invention describes a plant for cleaning contaminated industrial water, which comprises in series installed receiving reservoir, device for cleaning water from mechanical impurities, an electric flotator, an ultrafiltration unit, a desalination unit comprising a first-stage reverse-osmosis module and a second-stage permeate reverse osmosis module, and a filter for cleaning from ammonium ions, as well as a device for feeding chemical reagents, wherein between device for cleaning from mechanical impurities and electric flotator tubular coagulator is installed, and between the electric flotator and ultrafiltration unit there is an ozonisation unit, which includes two serially installed labyrinth columns and an ozone generator.EFFECT: technical result consists in increase of overall hydraulic efficiency, increase of degree of contaminated water purification and decrease of total amount of utilized concentrate.6 cl, 2 dwg

Description

Installation for purification of waste, drainage and oversludge waters of industrial facilities and disposal facilities for production and consumption waste

The invention relates to the field of environmental protection and can be used for purification of waste, drainage and oversludge waters with increased salt content, containing complex difficult-to-oxidize organic impurities up to the water quality standards of water bodies of fishery significance, including water bodies of specially protected natural areas (SPNA). The invention relates to multistage physicochemical methods for reagent treatment of contaminated industrial wastewater. The unit can be used at industrial facilities and facilities for the disposal of production and consumption waste for the treatment of wastewater, including technological, drainage and over-sludge wastewater to the required standards before being discharged into water bodies of fishery significance, including water bodies of protected natural areas or in recycling systems. water supply enterprises.

Known installation for purification and disinfection of water from natural highly contaminated sources (RU 2 652 705 C1, publ. 04/28/2018), containing a preliminary coarse mechanical cleaning filter with subsequent supply to the contact tank of ozonation. The volume of the contact container is designed in such a way that the time of contact between water and ozone is at least 20 minutes. The water treated with ozone is then fed to the ultrafiltration module, after which either all of the water to be treated or only a part of the water to be purified goes to the reverse osmosis membranes, depending on the required degree of desalination. The hydraulic efficiency of the installation, taking into account the reverse osmosis module, is about 60%. Permeate (purified water) enters the storage tank and then for the needs of the consumer, and the concentrate, after the reverse osmosis membranes, enters the storage tank, from which partial circulation is provided through the reverse osmosis module, or the resulting concentrate is discharged. In general, the installation is quite simple and economical in operation, it allows you to obtain drinking water, but at the same time it has a number of disadvantages:

1) there is no water treatment in the installation with chemical reagents, which in general reduces the depth and degree of purification;

2) the installation uses a single-stage contact reactor, which is insufficient for waters with a complex chemical composition of contaminants due to the difference in the rate of oxidation of the components;

3) the unit uses a single-stage reverse osmosis desalination of water both in terms of permeate and concentrate, which generally reduces the overall hydraulic efficiency;

4) the unit is designed for the purification of highly polluted, but natural waters and is not applicable for industrial effluents of complex chemical composition;

Known installation for the implementation of the method of wastewater treatment with the receipt of purified water and disinfected waste (RU 2 701 827 C1, publ. 01.10.2019), which allows you to purify wastewater to the standards of water quality of water bodies of fishery significance. Wastewater treatment to obtain purified water and disinfected waste includes wastewater treatment by means of a block-modular complex, in which preliminary mechanical wastewater treatment from large solid inclusions is carried out, followed by biological treatment and water saturation with atmospheric oxygen and additional treatment. Additional purification of water takes place in the module of adsorption and chemical oxidation or decarbonization, in which organic substances dissolved and suspended in water are oxidized with ozone, and the final additional purification of water to the standards for water quality of water bodies of fishery value is carried out on a reverse osmosis unit. The sludge and sediments formed in the treatment process are sent to the biological treatment module for re-processing, and then the precipitated waste is pumped into the mechanical treatment module, where they are dehydrated, disinfected and briquetted. In general, the installation provides a stable quality of cleaning in continuous mode, but at the same time has a number of disadvantages:

1) the presence of a biological treatment module significantly reduces the range of BOD values to the permissible load on activated sludge, as a rule, no more than 240 mg BOD / (g sludge-day);

2) the total salt content up to 2000 mg / dm ³ is also subject to limitation in the treated water;

3) the water to be treated must not contain mineral or organic toxic compounds;

4) the unit is designed for the treatment of only domestic or industrial waste water of equal quality.

The closest to the proposed one is an installation for the implementation of the method of purification of drainage waters of landfills of solid domestic waste (RU 2 589 139 C2, publ. 10.07.2016), which can be used to purify concentrated wastewater with difficult-to-oxidize organic impurities and toxic compounds. The installation includes a series-connected receiving tank, a pump, a self-cleaning filter for mechanical cleaning, electro-flotation destructors of the first and second stages, a tank, a pump, a sump, in front of which a coagulant alkali solution and a flocculant are fed into the water. The lower part of the settler is connected to a sediment compactor, which is connected to a vacuum dewatering unit. The upper part of the sump is connected to a tank with which a pump, a hollow fiber ultrafiltration module, a tank, a pump and a reverse osmosis membrane module of the first stage are connected in series, before which a dechlorinating agent, a solution for adjusting pH and an inhibitor of precipitation on the membrane are fed into the water, then a packed column, after which sulfate ions are added to the permeate, a second stage reverse osmosis module 32, after which an alkali solution is added to the water, two ion-exchange filters to remove sulfide ions and traces of ammonium, and an ultraviolet sterilizer. The method of purification of drainage waters of landfills at this installation includes the following stages: two-stage electrochemical treatment with the release of active chlorine and hydroxyl radicals at the anode, settling, ultrafiltration, two-stage reverse osmosis separation by permeate, water treatment with ion-exchange resins and ultraviolet sterilization. EFFECT: invention allows to purify drainage waters of solid waste landfills with a complex composition of organic inclusions up to MPC requirements for water of fishery reservoirs, however, it is not without its disadvantages:

1) high energy consumption at the stage of electrochemical cleaning;

2) increased formation of flushing water at the stage of ion exchange, and, as a result, low hydraulic efficiency;

3) there is no stage of reducing the volume of the resulting concentrate.

Nevertheless, due to its purpose and the presence of similar features, this installation was adopted as a prototype.

The technical problem solved by the proposed invention is to increase the degree of purification of waste, drainage and over-sludge waters of industrial facilities and objects of disposal of production and consumption waste, increase the overall hydraulic efficiency and reduce the total volume of utilized concentrate.

The technical problem is solved by an installation for the purification of polluted industrial water, containing a sequentially installed receiving tank-storage, a device for water purification from mechanical impurities, an electroflotator, an ultrafiltration unit, a desalination unit, including a first stage reverse osmosis module and a second stage reverse osmosis module for permeate, and a purification filter from ammonium ions, as well as a device for supplying chemical reagents, in which, according to the invention, a tubular coagulator is installed between the device for water purification from mechanical impurities and the electroflotator, and an ozonation unit is installed between the electroflotator and the ultrafiltration unit, including two serially installed labyrinth columns and an ozone generator ...

The technical result of the invention, which consists in increasing the degree of purification of contaminated water, is achieved through the implementation of two-stage ozonization of the purified water with an increased area of interaction with ozone in the labyrinth columns.

In addition, the degree of purification is increased due to the use of a zeolite filling filter as a filter for removing ammonium ions. The use of a zeolite backfill filter instead of an ion exchange filter can also reduce the formation of wash water and increase the overall hydraulic efficiency.

To reduce the volume of the resulting utilized concentrate, the desalting unit additionally includes a second stage reverse osmosis module for concentrate installed between the outlet of the first stage reverse osmosis module and its inlet.

In addition, to increase the degree of primary water purification from mechanical impurities, the device for water purification from mechanical impurities is a hydrocyclone.

In addition, a first mechanical cleaning filter is installed between the ozonation unit and the ultrafiltration unit, and a carbon filter and a second mechanical cleaning filter are sequentially installed in front of the desalination unit.

To reduce the water content in the sludge, the outlets of the device for water purification from mechanical impurities and the electroflotator for sludge and the outlet of the ultrafiltration unit for wash water are connected to a sump, the outlet of which for water is connected to a receiving storage tank.

The invention is illustrated by drawings.

FIG. 1 shows the technological scheme of the proposed installation for the purification of polluted waters.

FIG. 2 is a diagram of the labyrinth columns of the ozonation unit.

An installation for purification of waste, drainage and oversludge waters of objects and objects of disposal of production and consumption wastes (Fig. 1) contains a series-connected receiving tank-storage 1, a centrifugal pump 2, a device for primary water purification from mechanical impurities, which is a hydrocyclone 3, tubular coagulator 8. Tank 5 with coagulant solution and tank 7 of sodium hydroxide solution are connected to the pipeline in front of the tubular coalescer by means of metering pumps 4 and 6 to equalize pH, respectively. The tubular coagulator 8 is connected to the electroflotator 14 through a pipeline, to which a container 10 with a flocculant solution is connected by means of a metering pump 9. The electroflotator 14 is connected to a direct current source (DCS) 16. The outlet of the electroflotator 14 by means of a centrifugal pump 16 is connected to the inlet of the ozonation unit, which includes two successively installed labyrinth columns 17, 18 of ozonation (Figs. 1, 2). A circulation loop is connected to each column 17 (18), which includes a circulation pump 19 (21) and an ejector 20 (22). The ozone generator 46 is connected to the suction pipe of the ejector 22 of the second downstream column 18, which is connected with its upper part to the suction pipe of the ejector 20 of the first column 17.

Labyrinth columns 17, 18 ozonation can be direct-flow or counter-flow. In this diagram (Fig. 1, 2), the first column 17 along the flow of water is counter-current, and the second column 18 is direct-flow. Each labyrinth column 17, 18 (Fig. 2) includes a vertical body 46, inside of which there are horizontal labyrinth partitions 47 and a bubbler 48, the outlet openings of which for the outlet of the ozone-oxygen mixture are located in the lower part of the body 46. An overflow collection pocket is formed in the body 46 49 for treated water, which goes further to ultrafiltration. In the first downstream column 17, water is withdrawn from the bottom of the body 46 and is introduced into the bottom of the body 46 of the second column 18.

The outlet of the second column 18 ozonation by means of a centrifugal pump 23 (Fig. 1) through the first control cartridge filter 24 for mechanical treatment is connected to an ultrafiltration unit 25, which includes one or more ultrafiltration membrane water purification modules. An intermediate tank 26, a centrifugal pump 27, a carbon filter 28, a second control cartridge filter 35 for mechanical cleaning, a high-pressure pump 36, a desalination unit, an intermediate tank 42, a centrifugal pump 3 and a filter for cleaning ammonium ions are connected in series with the outlet of the ultrafiltration unit 25. is a zeolite fill filter 44.

The outlets of the hydrocyclone 3 and the electroflotator 14 for sludge and the outlet of the ultrafiltration unit 25 for wash water are connected through an intermediate tank 11 and a sludge pump 12 to a thin-layer lamellar flow-through clarifier 13, the outlet of which for water is connected to a receiving storage tank 1.

Tanks 30, 32 and 34 with antiscalant, sulfuric acid solution and sodium bisulfite are connected to the pipeline between the carbon filter 28 and the mechanical cleaning filter 35 by means of metering pumps 29, 31 and 33, respectively.

The desalination unit includes in series a reverse osmosis module 37 of the first stage and a reverse osmosis module 39 of the second stage for permeate, as well as a reverse osmosis module 41 of the second stage for concentrate, connected in series by means of a high pressure pump 38. In this case, the outlet of the reverse osmosis module 37 of the first stage for the concentrate is connected by means of a high pressure pump 40 to the inlet of the reverse osmosis module 41 of the second stage for the concentrate, the outlet of which is connected to the inlet of the high pressure pump 36.

The polluted water treatment plant operates as follows.

Waste, drainage or over-sludge waters of industrial facilities and production and consumption waste disposal facilities are supplied to the receiving storage tank 1, then by pump 2 for primary treatment to hydrocyclone 3. Hydrocyclone 3 allows water to be purified from mechanical impurities up to 10 microns in size. From the processed water flow, under the action of centrifugal forces, heavier mechanical impurities move to the lower part of the cone of the apparatus and in the form of sludge in a volume of not more than 10% of the main flow are discharged into an intermediate tank 11 and then by a pump 12 into a thin-layer lamellar flow-through settler 13, water separation and the sediment is organized according to the countercurrent scheme. Clarified water goes back to the receiving storage tank 1, and the compacted sludge for disposal. After primary cleaning on a hydrocyclone 3, a coagulant solution is introduced into the stream of purified water by a dosing pump 4 from a tank 5, and to equalize the pH, a sodium hydroxide solution by a dosing pump 6 from a tank 7. To increase the contact time, the treated water passes through a tubular coagulator 8, after which, for to intensify the cleaning process, the flocculant is dosed into the water flow by the dosing pump 9 from the tank 10.

Further, the stream of purified water is directed to the electroflotator 14 to extract heavy metals, reduce COD (chemical oxygen demand), BOD (biochemical oxygen demand) and the amount of suspended particles. The water to be cleaned enters the lower part of the electroflotator 14, after filling the installation with liquid, a constant current source 15 is turned on and voltage is applied to the electrodes. As a result of water electrolysis on the surface of the electrodes, there is a release of gas bubbles, which, rising upward, interact with dispersed particles of pollution with the formation of flotation complexes "particle-gas bubbles". The density of the resulting flotation complexes is less than the density of water, which causes them to rise to the surface of the water and form a foam layer - flotation sludge. The flotation sludge is periodically removed from the water surface with a scraper conveyor. Removal of flotation sludge takes place in a volume of 2% of the flow entering the electroflotator 14 into the intermediate tank 11 and then by the pump 12 into the thin-layer lamellar flow-through settler 13, the separation of water and sediment is organized according to a counterflow scheme. Clarified water goes back to the receiving storage tank 1, and the compacted sludge for disposal.

Further, the water to be purified is subjected to double ozonation in two labyrinth columns 17, 18 installed in series. Ozone-oxygen mixture is synthesized from concentrated oxygen and supplied from the ozone generator 45 to the ejector 22 of the second column 18, where it is mixed with the stream of purified water. Unreacted in the second column 18 ozone is fed to the ejector 20 of the first column 17, where it is mixed with a "fresh" portion of the purified water. To achieve the necessary mixing of the flow with the ozone-oxygen mixture, the purified water in the circulation mode is supplied to the ejector 20 by means of the pump 19 to the ejector 22 by means of the pump 21. The spent ozone-oxygen mixture (air mixture) enters the destructor (conventionally not shown) and then into the atmosphere ... From the labyrinth columns 17, 18, the purified water by the pump 23 is discharged to a control cartridge filter 24 for mechanical cleaning, which is used to clean the liquid flow from insoluble mechanical impurities before the ultrafiltration unit 25. The drainage is removed in the amount of 0.5% of the incoming flow to the filter 24 to the sump 13 through the intermediate tank 11.

For guaranteed removal of organic impurities and small particles from the stream of purified water, ultrafiltration modules of the ultrafiltration unit 25 are used. Ultrafiltration membranes work on the “inside-out” principle, which means that the supplied water flow in filtration mode flows from the inside of the capillaries to the outside, and in the backwash mode, the water flows in the opposite direction, that is, from the outside to the inside of the capillaries. The modules operate in tangential mode to prevent excessive build-up of deposits on the membrane surface. High speeds of tangential flow create turbulence in the water supply channel, providing a high efficiency of cleaning the surface from accumulated contaminants, which is especially effective for water with a high content of insoluble suspended solids. To maintain a high flow rate, a part of the resulting concentrate is returned to the ultrafiltration modules (recirculation) and mixed with the main stream of treated water. The remaining concentrate in the amount of 20% of the incoming flow to the ultrafiltration modules is discharged into the settler 13 through the intermediate tank 11. To maintain productivity, the ultrafiltration modules are subjected to short pulse flushes during operation with alternating acid and alkaline phases. The wash water from the ultrafiltration unit 25 is directed to the settler 13. The water purified from the main contaminants is collected in the intermediate tank 26, from where it is pumped to the coal filter 28 to remove volatile phenols and possible residues of oil products. Further, the water to be purified through the control cartridge filter 35 of mechanical cleaning by the pump 36 is supplied to the desalination unit to the reverse osmosis module 37 of the first stage. Before entering the reverse osmosis membranes, an antiscalant, a solution of sulfuric acid and sodium bisulfite (antioxidant) are dosed into the flow of purified water by metering pumps 29, 31, 33. Solutions of chemical reagents are prepared in containers 30, 32, 34. On reverse osmosis membranes, the purified water is divided into two streams: permeate - demineralized pure water and concentrate - water containing dissolved salts. Separation into permeate and concentrate on the first stage reverse osmosis module 37 is carried out in a ratio of 75/25 as a percentage of the input stream. The permeate of the first stage is supplied by a pump 38 to the reverse osmosis module 39 of the second stage according to the permeate, where it is separated into the second stage permeate and the second stage concentrate in a ratio of 80/20 in percentage. The concentrate of the first stage, formed on the reverse osmosis module 37, in order to increase the degree of permeate recovery, is fed by the pump 40 to the reverse osmosis module 41, where it is re-divided into permeate and concentrate in a 60/40 ratio. The permeate from the reverse osmosis module 41 enters the inlet of the pump 36, and the concentrate is disposed of. The second stage concentrate formed on the membranes of the reverse osmosis module 39 is partially fed to the inlet of the pump 38 and partially to the inlet of the pump 36. The permeate after the second stage of reverse osmosis treatment enters the intermediate tank 42, from where the pump 43 is fed to the final cleaning stage - cleaning from ammonium ions. The removal of ammonium ions is carried out in the filling filter 44. The filter filler is a natural zeolite - clinoptilolite. The total hydraulic efficiency of treatment according to the proposed scheme is at least 85% of the contaminated water entering for treatment.

Further, the permeate that meets the water requirements of fishery facilities is supplied to open water bodies.

Claims (6)

1. Installation for the purification of polluted industrial water, containing a sequentially installed receiving tank-storage, a device for water purification from mechanical impurities, an electroflotator, an ultrafiltration unit, a desalination unit, including a first-stage reverse osmosis module and a second-stage reverse osmosis module for permeate, and a filter for cleaning ammonium ions, as well as a device for supplying chemical reagents, characterized in that a tubular coagulator is installed between the device for water purification from mechanical impurities and the electroflotator, and an ozonation unit is installed between the electroflotator and the ultrafiltration unit, including two successively installed labyrinth columns and an ozone generator. 2. Installation according to claim 1, characterized in that the filter for purification from ammonium ions is a zeolite-filled filter. 3. Installation according to claim 1, characterized in that the desalting unit additionally includes a second stage reverse osmosis module for concentrate installed between the outlet of the first stage reverse osmosis module and its inlet. 4. Installation according to claim 1, characterized in that the device for water purification from mechanical impurities is a hydrocyclone. 5. Installation according to claim 1, characterized in that a first mechanical filter is installed between the ozonation unit and the ultrafiltration unit, and a carbon filter and a second mechanical cleaning filter are sequentially installed in front of the desalination unit. 6. Installation according to claim 1, characterized in that the outlets of the device for water purification from mechanical impurities and the electroflotator for sludge and the outlet of the ultrafiltration unit for rinse water are connected to a sump, the outlet of which for water is connected to a receiving storage tank.

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