SU1430353A1 - Apparatus for treating waste water - Google Patents

Abstract

The invention relates to wastewater treatment plants for suspended particulate matter and petroleum products. The purpose of the invention is to reduce the water content of petroleum products and increase the efficiency of wastewater treatment. This goal is achieved by the fact that the float trays with an inclined foam collector screen are equipped with a mechanism for the vertical movement of a periodic action.

Description

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in the flotation cells, vertical partitions-electrodes of various lengths are spaced apart from each other, decreasing from the center to the periphery in proportion to the pressure drop in the flotation section, while the slotted pipes of the drainage distribution system are equipped with external end quick-release plugs, and on the vertical partitions Electrodes are supplied by pulses of alternating current of industrial frequency with voltage of 30-40 V. The device includes in series flotation chambers 1 and 2 arranged in one housing with ikaln1mi electrodes 3-septate, float penosbornye trays 4 with naprayl yuschim screen 5, the vertical mechanism premeschenie batch

6, filter chamber with coalescing load 7, fast filter filter with granular load 8, pipes for removing oil spam 9 and collecting wash water 10, systems of perforated pipes 11 for distributing water-air mixture, grid 12, drainage distribution system of slotted pipes 13, pumps 14, 15, 16 for supplying source liquid, washing and recirculation water, ejectors 17, pressure tanks 18 and 19, pressure gauges 20, safety valves 21 with vent valves 22, reduction valves 23, suction lines 24 and 25 of pumps, pressure pipes 26- 30 with back kami ,, collector 31, .truboprovod 32 for withdrawing filtrate tank 33. The pure water zp 2, f ly-8-yl.

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The invention relates to devices for the treatment of waste water from petroleum products, fats, suspended and surfactants by pressure flotation, electroneutralization of the surface layer of petroleum droplets and filtration through dense granular materials and can be used in many folk industries, for example, for purification of rain sewage from the territories of machine-building enterprises and oil depots, production drains of motor and car repair enterprises, oil refineries petrochemical plants, thermal power plants, ports, etc.

The aim of the invention is to reduce the water content of petroleum products and increase the cleaning efficiency.

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Figure 1 shows schematically

device, longitudinal section; FIG. 2 is a section A-A in FIG. 1; FIG. 3 is an axonometric diagram of floating float trays with an inclined foam panel; Fig. 4 shows piping systems for distributing the air / water mixture in the flotation cells; on

Fig. 5 shows a slit pipe system for supplying wash water; Fig. 6 is a drainage distribution system.

from the punched pipes; figure 7 - scheme of drainage of the filtrate; on Fig diagram of the supply of wash water.

The device includes successively located in the same housing (Figures 1 and 2) flotation chambers 1 and 2 with vertical partitions-electrodes 3, float foam collecting trays 4 with an inclined screen 5 directing the flow of foam, a periodic movement mechanism 6 of periodic action, a filter chamber with a coalescing loading 7, a fast filter chamber with a granular loading 8, pipes for removing oil sludge 9 and

flushing water discharge 10, a system of perforated pipes 11 for distributing the water-air mixture, a grid 12 for maintaining a floating coalescing load, a drainage

a distribution system of slotted pipes 13 for draining the filtrate and supplying the washing water, pumps for supplying the initial liquid 14, washing 15 and recycling water 16,

ejectors 17 on the bypass lines of pumps, pressure tanks 18 and 19 for saturating the initial fluid and radial water with air, pressure gauges 20, safety valves 21 with Vantu-22, pressure reducing valves 23, suction lines, 24 and 25 pumps, pressure pipes 26 -30 with valves, collector 31, pipeline 32 for removal of filtrate, clean water tank 33.

In this case, the structure for collecting the frothy product (FIG. 3) includes. corner pieces for connecting with 10

Sewage water containing heavy and light phases by pump 14 through pipelines 26 and 27 is supplied after saturating it with air through ejector 17 on the bypass line of pump 14, dissolving the air in pressure tank 18, releasing pressure i by pressure reducing valve 23 in pipe 27 and equals . dimensional distribution over the chamber area by means of a system of perforated pipes 11 into the flow chambers 1 of flotation. When the waste liquid moves upwards in chambers 1 of a float-floating tray with screen 34, foam 15 DI contamination particles contact collecting trays 4, floats 35, directing the flow of foam, inclined screen 5, pipes 9 for removing oil spam, guide racks 36, movement brackets for float trays 37, 20; flexible connections of the plates with the control rod 38.

The design of distribution systems for water-air mixtures includes

with air puffs and carried to the surface as a frothy product. The partially clarified liquid enters the counter flow chamber 2 of the flotation and moves from top to bottom. At the same time, the bottom of the flotation chamber 2 is pumped 16 (with the valve closed on the suction line of the pump 15) and clarified liquid from reservoir 33 (with a volume of 20-50% of the initial fluid volume) is fed through pipelines 29 and 30 after saturation with air through the ejector 17 on the bypass line of the pump 16, dissolving the air in the pressure tank 19, relieving the pressure by reducing valve 23 on the pipeline 30 and evenly distributing the chamber area using a system of perforated pipes 42.

supplying an air-saturated source water pressure supply pipe 27, a pressure reducing valve 23 for relieving pressure j a main ring pipe 39, branches from perforated pipes 40 for pores (air flow-fed recirculation water - pressure supply pipe 30, pressure reducing valve 23 for relieving pressure, the main ring pipe 41, the branches of the perforated pipes 42.

The design of the slotted pipe system for supplying wash water includes a main ring pipe

43, offshore conduit branch

44, branches of perforated pipes 45.

The design of the drainage distribution system includes a pipeline 32 for draining the filtrate with a valve, a pipeline 28 for supplying wash water, with a valve, a collector 31, branches 46, end plugs 47, revision 47.

The design of the slotted pipes for draining the filtrate and supplying the washing water includes a tube-case 48 for supplying the washing water with a longitudinal slot in the lower part, perforated

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with air puffs and blown out to the surface as a frothy product. The partially clarified liquid enters the counterflow chamber 2 of the flotation and moves from top to bottom. At the same time, from below, into the flotation chamber 2, pump 16 (with the valve closed on the suction line of pump 15), suction line 25 and pipelines 29 and 30 supply clarified liquid from reservoir 33 (with a volume of 20-50% of the initial fluid volume) after saturating it air through the ejector 17 on the bypass line of the pump 16, dissolving the air in the pore tank 19, relieving the pressure with a pressure reducing valve 23 in the pipe 30, and evenly distributing it over the chamber area using a system of perforated pipes 42.

The flotation aggregates of the particle contamination — air puffed out from the flotation chamber 2 to the surface and together with the flotation sludge from the flotation cells 1 form the surface layer of the oil spam. The mechanism 6 for moving the batch vertically according to a predetermined program enters into operation a structure for collecting non-teslama. In this case, the lowering of the structures occurs evenly, which is provided by the control rod 38.

Surface oil spikes moving along the inclined plane of the screen 5 from the center to the periphery are collected in chaps 4 and, as they accumulate, are discharged into collecting tanks through pipes 9..

Connection float trays 4 with an inclined screen 5 detachable

The pipe 49 for removal of the filtrate with straps allows for measuring slits in the upper part.

The device works as follows.

Sewage water containing heavy and light phases by pump 14 through pipelines 26 and 27 is supplied after saturating it with air through ejector 17 on the bypass line of pump 14, dissolving the air in pressure tank 18, releasing pressure i by pressure reducing valve 23 in pipe 27 and equals . dimensional distribution over the chamber area by means of a system of perforated pipes 11 into the flow chambers 1 of flotation. When moving the waste fluid from the bottom up in the chambers 1 of the flotation unit, the contamination particles contact

with air puffs and carried to the surface as a frothy product. The partially clarified liquid enters the counter flow chamber 2 of the flotation and moves from top to bottom. At the same time, the bottom of the flotation chamber 2 is pumped 16 (with the valve closed on the suction line of the pump 15) and clarified liquid from reservoir 33 (with a volume of 20-50% of the initial fluid volume) is fed through pipelines 29 and 30 after saturation with air through the ejector 17 on the bypass line of the pump 16, dissolving the air in the pore tank 19, relieving the pressure with the pressure reducing valve 23 on the pipeline 30 and evenly distributing the camera area by means of a system of perforated pipes 42.

The flotation aggregates of the particle contamination — the air puffed out from the flotation chamber 2 to the surface and together with the flotation sludge from the flotation cells 1 form the surface layer of the oil spam. The mechanism 6 for moving the batch vertically according to a predetermined program puts into operation a structure for collecting oil sludge. In this case, the lowering of the structures occurs uniformly, which is ensured by the control rod 38.

Surface oil spikes, moving along the inclined plane of the screen 5 from the center to the periphery, are collected in trays 4 and, as they accumulate, are discharged into collecting tanks through pipes 9..

Connection float trays 4 with an inclined screen 5 detachable

the fasteners make it possible to vary the distance between the tray and the screen and adjust the dimensions of the foam channel. Change buoyancy

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floats, you can adjust the degree of immersion of the tray under the level of a layer of sludge when you turn off the mechanism 6 of the vertical movement.

Dividing the volume of chambers 1 and 2 of flotation into thin-layer channels with vertical partitions-electrodes allows reducing the turbulence of flows, eliminating the formation of circulation zones, and organizing along the flotation process the copelling process,

The intensity of the process of enlargement and the emergence of oil droplets is multiplied by the electric field of the electrodes when the alternating current pulses are supplied to the industrial frequency with a voltage of 30-40 V. With destruction of the stability of the emulsion particles in an alternating field of electrodes by neutralization or destruction of the surface charge formed by adsorption or by chemisorption of ions or polar molecules of water, a tenfold purification effect is achieved at an oil concentration up to 10 mg / l and a hundredfold - at concentrations of petroleum products up to 100 mg / l and above.

The pulsed electric field, ensuring the removal of surface charge from particles of petroleum products, makes it possible to reduce the power consumption by more than a hundred times. The duration of the period between pulses depends on the rate of emergence of oil sludge particles, i.e. their residence time in the flotation protection chamber 2, and may vary within 10–20 minutes. The pulse duration is 15–20 s.

A uniform distribution of the flows of the initial fluid and the recirculating water-air mixture is achieved by using plates of different lengths and different distances between them, varying linearly from the periphery to the center.

The liquid clarified in the flotation chambers then passes through a layer of floating coalescing load (for example, from particles of granular or lump polyethylene, foam plastic, polyurethane foam, etc.) held by the grate 12. At the same time, particles of petroleum products are retained on the surface of the loading particles, coalesce and float to the surface. When filtering waste fluid che1430353 6

cut coalescing load layer pro-. the final degassing of the filter takes place before it enters the layer of loading of the FAST filter, which prevents its blockage under the air of the air. The presence of a large-pore coalescing load prevents the quick filter from loading the filter from forming a large flake film on it, while washing the loading of the fast filter fills the pores of the coalescing load and due to the large abrasive effect both loads are liberated intensively from soiling.

The final purification of waste liquid from suspended solids and oil products takes place in the loading of the fast filter 8. The clarified water is discharged through slotted pipes 13 of the drainage distribution system connected to the pipe-cases to supply the washing water, flows into the pipeline 32 and then pipeline 28 through pipeline 32 enters the clean water tank 33.

The flushing of the load 8 of the fast filter and the coalescing load 7 is carried out by supplying water from the clean water tank 33 with a pump 15 at. closed valves on the suction pipe of the pump 16 and pipe 32 and open valves on the suction pipe of the pump 15 and pipe 28. Wash water flows into the filtering feed from the annular space between the slotted pipe to collect the filtrate AND the slotted wash water pipe. The flushing is carried out by upward flow at dynamic equilibrium of the expanded layer of loading 8 of the fast filter and in the pores of the coalescing load 7. The flushing water is discharged through pipes 10 from the bottom of the flotation chambers 1.

At the same time, floatation and removal of coarse dispersed particles of air by air bubbles in the flow chamber of flotation, and thinner cleaning of the initial fluid by flotation of fine particles from the flow chamber of flotation and additional mass of air bubbles formed during depressurization in the counterflow chamber. from recirculated water. Creation of thin-layer flows in the flotation cells using vertical re-35

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The camp allows to significantly reduce the level of flow turbulence, eliminate the possibility of forming circulation zones and thereby improve the conditions for the formation and removal of flotation reagents. The supply of pulses of alternating current at the frequency to the vertical partitions - electrodes in the flotation chambers destroys and neutralizes the surface charge of the droplets of oil products, thereby improving the conditions for their contact, flotation, and coalescence.

The device of external quick-detachable plugs at the ends of the perforated pipes of another drainage distribution system makes it easy to clean and replace them.

The device controlled floatable trays with an inclined foam collector screen allows you to simplify the foam product system and ensure minimum water sludge flow, which, on the one hand, allows for more rational use of water resources, and on the other - more rational and less costly to utilize oil products .

The proposed device in comparison with the known institute provides an increase in the efficiency of wastewater cleaning from suspended solids and oil products by a factor of 2-3 due to an increase in: the degree of gasification (in clarified liquid and in improving the hydraulic conditions of flotation of soils in thin-layer channels of pressure flotation cells, intensification the process of coalescence and floating of oil products

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electrically neutralizing the surface charge of the droplets, improving the foam product collection system and the distribution system from the slotted pipes to drain the filtrate and supplying wash water, and also reduce the water content of oil products by more than ten times.

Claims (2)

1. A device for wastewater treatment, including a housing with successively arranged countercurrent and continuous flotation chambers, equipped with vertical partitions-electrodes, float chutes with an inclined suction screen, a filtration chamber with a coalescing load, a filtration chamber with a granular charge, supply nodes for the original liquids, washing and recirculation water, drainage distribution pipe, differing in the fact that, in order to reduce the water content of oil products and to reduce it. Neither the wastewater treatment efficiency, the device is equipped with a periodic movement mechanism intermittently interacting with the foam collection screen, the vertical partitions-electrodes are of a different length, and the distance between them decreases from the center to the periphery. 2. The device according to claim 1, is different because the ends of the slotted pipes of the drainage and distribution system are provided with stoppers. 77 (f fisj.b 4Г7 FI.2 (f3U9.Z ъ ff4 46 fr "Wf- 2 ff (fjus.6 ZG rig 7 tffuS.e