RU2470871C1 - Water flotation-filtration treatment apparatus - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to treatment of effluents and is intended for cleaning water of oil and oil products by surfactants and finely dispersed light suspensions. Proposed flotation-filtration plant consists of reinforced concrete bath 1 divided by transverse inclined bulkhead 2 into chamber 3 for mixing water with water-air mix and flotation-filtration chamber 4, compressor 8, flotation slime discharge trough 7, rinsing pump 10, circulation pump 11, air blower 12 and filter 6 made up of filtration element composed by detachable sections resting on frame consisting of bearing elements. Note here that said detachable sections represents stiffness ribs secured on frame and provided with V-like cross-section wire welded thereto.

EFFECT: efficient water treatment, lower assembly costs.

5 cl, 7 dwg

Description

The invention relates to a device for the treatment of industrial wastewater and is intended for the purification of these waters contaminated with oil waste, products of its processing, fats, oils, products of organic synthesis, surface-active substances, finely dispersed light suspensions.

A known installation for wastewater treatment, including located above each other, a filter chamber with a granular charge and a flotation chamber with devices for introducing air and removing foam (ed. St. USSR No. 485075, CL 02F 1/40, 1973).

A disadvantage of the known installation is the bulkiness and complexity, as well as the significant residence time of the wastewater in the flotation unit, which does not provide a high treatment effect for oily wastewater.

A known installation for flotation water treatment, containing the main flotation chamber, a centrifugal pump, a contact flocculation chamber is installed, connected in series with the flotation chamber by means of perforated pipes configured to supply purified water to the foam layer of the chamber, and the flotation chamber is equipped with microporous filter tubes for passing through air, also the flotation chamber is connected in series with the purified water collection chamber, the centrifugal pump is connected n with a purified water chamber, the hydraulic elevator is connected by a pressure pipe to a centrifugal pump and a sewage pipe. RF patent No. 2272786, IPC C02F 1/24, B03D 1/14, publ. 03/27/2006.

A known installation for flotation-filtration water purification, containing in the upper part a technological unit including a flotation chamber and a filter placed in a single unit casing, in the lower part there is a tank for accumulating purified water, as well as separately installed pumping unit, ejector with a atmospheric supply pipe air, a saturator and a piping system, according to the invention, the flotation and filtration chambers of the technological unit are located in a horizontal plane, represent sensible capacity, structurally formed by sequentially placing a single axis of symmetry in the direction from the housing wall toward the center of the last few structural elements: a baffle shaped as a ring with a cut out along the entire height of the ring element (segment) allowing the formation of the band structure of the flotation cell; a limiting cylinder, which forms, together with sectional walls installed between the outer surface of the latter and the surface of the housing, a cavity of flotation zones and a cavity for collecting foam product made with the possibility of overflow of swotted water from the second zone of the flotation chamber into the transitional technological zone due to the presence of holes in the bottom parts of the restriction cylinder; a separation and overflow partition separating the flotation chamber from the filtration chamber and made in the form of a cylindrical pipe with half-openings at the upper end and having a vertically mounted plate inside, the height of which is less than the height of the cylindrical pipe, dividing the pipe cavity into small and large zones; a container for the accumulation of purified water is placed in a single unit casing and is connected to the process unit via an inlet pipe.

RF patent No. 2254297, IPC 7 C02F 1/24, B01D 36/00, publ. 06/20/2005.

The device in question provides a high degree of purification of the liquid from dispersed impurities. However, it is complex in design.

The technical task of the invention is to create a technological, universal device for effective water purification with the regeneration of filter elements during operation, uniform distribution of hydraulic load in the deposition zone, and reducing installation costs, increasing the working surface of the drainage-washing system.

This problem is solved due to the fact that in a flotation-filtration unit, consisting of a reinforced concrete bath, divided by a transverse inclined partition into two parts - a chamber for mixing purified water with an air-air mixture and a flotation-filtration chamber, including a compressor, a chute for flotation sludge, a washing pump , a recirculation pump, a blower and a filter, the filter consists of filter elements in the form of removable sections resting on a frame made of support elements, while the removable sections represent fight mounted on the frame ribs, on which by means of spot welding wire secured, which has V-shaped.

In addition, the sections create a rigid screen with slits ranging in size from 20 to 2000 μm and with a tolerance of a gap width of up to ± 15 μm.

In addition, the wire profile is straight.

In addition, the wire profile is located at an angle of inclination α.

In addition, the angle of inclination of the wire α can be from 0 to 10 degrees.

The invention is illustrated by drawings.

Figure 1 is a schematic diagram of a flotation filtration plant.

Figure 2 - General view of the installation for flotation-filtration water treatment.

Figure 3 - easily removable structural element of the type "false bottom" based on welded slotted products.

Figure 4 - pipe perforated to supply flushing and selection of purified water.

Figure 5 - collector - a system of perforated pipelines for supplying air during backwashing.

6 is a cross section of the filter element is a variant with a direct arrangement of the wire.

7 is a cross section of the filter element is an option with an oblique arrangement of the wire.

The flotation-filtration installation consists of a reinforced concrete bath 1, divided by a transverse inclined partition 2 into two parts - a chamber 3 for mixing purified water with an air-air mixture and a flotation-filtration chamber 4, in the upper part 5 of which flotation is carried out, and in the lower part 6 - filtration. In the upper part 5 there is a gutter 7 for the withdrawal of sludge and wash water. The flotation-filtration unit includes a compressor 8, which serves to supply pressure air to the saturation chamber 9, a washing pump 10, a recirculation pump 11, a blower 12. A throttling system 13 is installed in the mixing chamber 3 in the form of a reducing valve to form

water-air mixture. The drainage bottom 14 of the flotation-filtration chamber 4 is a filter, which consists of filter elements in the form of removable sections 15, supported by a frame 16 made of supporting elements in the form of an I-beam, under the drainage bottom 14 there are a collector 17 for washing and withdrawing purified water and a collector 18 air supply when flushing. In the side wall of the flotation-filtration chamber 4, there is a fitting for supplying air 19 and a fitting 20 for discharging purified water and supplying washing water. Sections 15 are stiffeners 22 fixed to the frame 21, on which a wire 23 is fixed by spot welding, the profile of which has a V-shape. Sections 15 create a rigid screen with slits from 20 to 2000 μm in size and with a tolerance of up to ± 15 μm in slot width, with a straight or inclined arrangement of the wire profile. The angle of the wire α can be from 0 to 10 degrees.

A clamping bar 24 and an eye for mounting 25 are mounted on the frame 21.

The collector 17 for washing and sampling the purified water consists of steel perforated pipes 26 forming a closed loop with a welded flange 27.

The collector 18 of the air supply during washing consists of steel perforated pipes 28 forming a closed loop with a welded flange 29.

Those parts of the unit that come in contact with water are made of stainless steel.

The technological process of flotation-filtration is as follows.

Water and compressed air are supplied to the saturation chamber 9 by the circulation pump 11 from the compressor 8. The purified water is supplied to the mixing chamber 3 and mixed with water saturated with air in the chamber 9. At the outlet of the saturation chamber 9, a throttling system 13 is installed in the form of a pressure reducing valve discharged and a huge amount of small bubbles or water-air dispersion forms in the water. After mixing the purified water with the air-air dispersion, the smallest bubbles sorbed on the surface of the particles of contaminants raise them to the surface and transfer them to the flotation-filtration chamber 4, in the upper part 5 of which flotation is carried out, and in the lower part 6 - filtration.

Contaminants accumulate on the surface of the water in the form of a slurry, and when flushing, they enter the trough 7 to remove the flurry sludge and wash water. The water purified by pressure flotation, under the action of gravity, passes through the filtration part 6 of the installation. Gradually, the drainage bottom 14 of the flotation-filtration chamber 4 becomes clogged, which leads to an increase in hydraulic resistance and, as a consequence, a decrease in the filtration rate.

The washing of the drainage bottom 14 is carried out by a counterflow of water from the washing pump 10 in two stages. In the first stage, before washing from below, air is supplied from the blower 12 to the filter, significant flow turbulence occurs inside the filter slots, which loosens the filter load and prepares it for washing. Then the flushing liquid is supplied and the filter is flushed. The air supply and the supply of washing liquid alternate, which allows for more uniform cleaning of the entire filter surface. Also, air can be supplied with periodic shocks along with the washing liquid. The filter consists of filter elements in the form of removable sections 15, based on the frame 16, in case of failure, allowing their quick replacement.

Advantages of filter elements based on welded slotted products:

- high coefficient of open surface (clearance);

- uniform distribution of the flow of raw materials;

- quick and easy installation of large areas (the weight of one element does not exceed permissible norms);

- low ability to clog;

- the ability to operate under significant loads;

- high accuracy of slots (slot width from 0.02 to 20 mm);

- perfectly smooth smooth surface.

The use of V-shaped wire provides special hydraulic properties of the filter element.

Claims (5)

1. Flotation-filtration installation, consisting of a reinforced concrete bath, divided by a transverse inclined partition into two parts - a mixing chamber for purified water with a water-air mixture and a flotation-filtration chamber including a compressor, a chute for flotation discharge, a washing pump, a recirculation pump, a blower and a filter characterized in that the filter consists of filter elements in the form of removable sections supported by a frame made of support elements, while the removable sections are fixed a frame stiffener, on which by means of spot welding wire secured, which has V-shaped. 2. The flotation-filtration installation according to claim 1, characterized in that the sections create a hard screen with slots of size from 20 to 2000 microns and with a tolerance of a slit width of up to ± 15 microns. 3. Flotation-filtration plant according to claim 1, characterized in that the wire profile is located directly. 4. Flotation-filtration installation according to claim 1, characterized in that the wire profile is located at an angle of inclination α. 5. Flotation-filtration plant according to claim 1, characterized in that the angle of inclination of the wire α can be from 0 ° to 10 °.

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