SU1738760A1 - Plant for deironing of underground waters - Google Patents

Abstract

Use: for purification of natural groundwater, namely for deironing. SUMMARY OF THE INVENTION: The installation includes an aeration device, a contact tank, and slow filters mounted on each other. Water from the contact tank is fed to the filter loading through a trough along the perimeter of the filter; a perforated diaphragm is fixed at the edge of the trough; its perforation is made in the form of nozzles equipped with floats. The operation of the installation is provided with free access to valves and fittings, the regeneration of the filtering load is simplified by hydro-removal with reverse flow of water, and the upper layer of the loading is not clogged. 2 Il.

Description

The invention relates to installations for the purification of natural groundwater, namely, low-performance iron removal plants.

The aim of the invention is to simplify operation.

This goal is achieved by the fact that in an installation for deironing groundwater, including an aeration device, a contact tank and a two-level slow filter with a granular load, equipped with an initial water supply system and a drainage system to drain the filtrate, the slow filters are pressure and are installed on each other, and the water supply system is designed as a gutter around the perimeter of the filter with a flexible perforated diaphragm fixed to

the edge of the gutter with the separation of the gap when discharging industrial water.

The proposed installation can perform the role of a bioreactor with the function of providing the viability of iron bacteria in the biofilm on the surface of the charge, releasing dissolved iron compounds from water; sedimentation tank of sediment with the function of retaining a part of the formed iron hydroxide on the surface of the diaphragm, to prevent the entire amount of suspended matter from falling onto the filtering surface of the charge; an incliner with the function to provide the sludge washout from the diaphragm surface into the collecting chute when the filter is rinsed with a reverse flow of water; the closure member with the function of opening the gap for access of the washing water and sediment removed from the loading surface into

vi with

00

Vi o o o

the collecting trench when washing it by the return current of water.

FIG. 1 shows the installation, section; in fig. 2 — node I in FIG. one.

The installation includes an aeration device 1 placed above the contact reductor 2 connected by a pressure pipe 3 with slow filters 4 mounted on each other. The upper part of the slow filters 4 is divided by a flexible perforated diaphragm 5 into the upper 6 and lower 7 Russa, the perforation of the diaphragm 5 is fitted with fittings 8 and floats 9, the diaphragm 5 is fixed with the help of stops 16 on the edge of the collecting channel 10 with the formation of a gap 15 when flushing with reverse flow of water. Slow filters have a filtering load 11c of a catalytic film previously formed on the surface of its grains, laid on supporting layers of a drainage system 12, communicated with a collecting pipeline 13 for draining clean water and with a nozzle 14 for supplying wash water. The collecting chute 10 is connected to the pipeline 17 for draining the wash water and the sludge.

The installation works as follows.

Water containing dissolved iron compounds from an underground water source using, for example, submersible artesian pumps installed in water wells, is fed into an aeration device 1 located above the contact tank 2. A sprinkler, such as a perforation pipe, can be used as an aeration device 1 and with a high concentration of dissolved gases, in particular carbon dioxide, it is possible to use vacuum-ejection devices, which can reduce the tion of dissolved gases and to ensure the absorption of oxygen in the treated water. It is advisable to place the contact tank 2 at the points providing the necessary free pressure at the points of water extraction of the distribution network. In this case, it performs the function of a pressure regulating tank.

From the contact tank 2, the treated water through the pressure pipeline 3 flows into the upper part of the slow filters 4 installed on each other. The upper part of the slow filters 4 is divided by a flexible perforated diaphragm 5 made, for example, from a polyethylene film, into the upper b and lower 7 Russ. In the upper rusa 6 of the filters 4, some of the iron compounds in the form of hydroxide flakes settle (up to 30-50% of the initial concentration of iron) and precipitate on the surface of the flexible diaphragm 5. From

In order to form a zone of sediment accumulation, the perforation of the diaphragm 5 is provided with fittings 8 protruding 30-40 mm above the surface of the diaphragm 5. To increase the length of the settling zone

perforations with fittings 8 are made only in the middle part of the diaphragm. To reduce the deformation of the diaphragm 5 that occurs when sediment accumulates on its surface, the nozzles 8 are fixed

floats 9, partially compensating for the mass of sediment due to its buoyancy.

After upholding a part of the iron compounds in the upper russia 6, the purified water through nozzles 8 enters the lower rus 7,

moreover, the cleaned water does not flow into the lower rus 7 through the collecting chute, since the diaphragm 5 with its lower surface is adjacent to the drain edge of the collecting chute 10. From the lower tusk 7, water is filtered through a granular load 11 having a capacity of 0.75 m (with a speed of 0, 1-0.2 m / h. Due to the fact that the period of formation of a catalytic film on the loading grains at low filtration rates is very long (up to 20 days or more), during this period the iron content in the filtrate can significantly exceed the maximum allowable its concentration; loading d laying it in a pre-filter 4 is charged due to the passage therethrough of water containing iron, at a rate of filtration 5-7 m / h for several hours to form on the surface of catalyst grains of the film. Such charging

can be made on a special filtering column or directly in the filters 4, alternately passing the source water through them with the specified filtration rate. When filtering cleaned

water through charging 11 with a catalytic film previously formed on its grains, the water is completely cleared of iron and drained system 12 is discharged into the collecting pipeline 13 connected to

divorcing network. The pressure in the network at the same time corresponds to the water level in the contact tank 2 and the loss of pressure in the slow filters 4, valves and pipelines 3 and 13.

As they filter, iron compounds accumulate in the upper layer of the filtering charge 11 and form a precipitate on its surface. Ferrous sediment accumulating on the surface of the diaphragm 5 and

load 11, has a loose structure and a relatively high permeability, and iron bacteria are included in the sediment, contributing to an increase in the intensity of the iron oxidation process and its release from solution. After the formation of a biofilm on the surface of the load 11, the main part of the iron compounds in the water being treated is retained in the biofilm layer, does not penetrate deep into the filter load 11 and reduce the intensity of growth of pressure loss (filtration resistance).

Due to the low growth rate of head loss in load 11, not exceeding 0.2-0.5 cm / day on average, the duration of the filter cycle is 250-350 days. After reaching the limiting values of the pressure loss as a result of the closure of the upper layer of the load 11 and accumulation of sediment on its surface, the flow of the source water through the pipeline 3 to the filter 4 and the discharge of the filtrate by the drainage 12 stops. In the pipe 14 provide the flow of wash water, for example, a mobile pump installation from a tank truck or from the drain 12 parallel operating filters 4. When washing the load 11 reverse flow of water diaphragm 5 (Fig. 2) takes the upper position (dotted line), opening the gap 15 between it the bottom surface and the edge of the collecting chute 10, to which the diaphragm 5 is fixed with the help of the stops 16. The washing water with suspended sediment enters the collecting chute 10 (arrows), and through the fittings 8 - into the upper rus 6, the sediment accumulated on the diaphragm surface GMs 5, and a collecting gutter 10 by which is withdrawn in line 17 and is discharged into the sewers. Flushing of the filter loading 11 of the slow filters 4 is carried out alternately

and

in each of them, after which the filters 4 are again brought to the operating mode by appropriately switching the shut-off organs (gate valves).

Compared to the known, the proposed plant for deferrization of groundwater has significantly smaller overall dimensions in terms of, can be interlocked with a water tower and can be used for water purification in standalone mode, without requiring significant operating costs. In addition, the installation is used in operation remote from centralized water supply systems.

systems of objects, such as pioneer lagers, livestock farms with water consumption in the range of 20-75 m3 / day. With a high sanitary reliability, the operation of the installation as compared to the known one is simplified due to the possibility of hydraulic regeneration of the load, the absence of the need to periodically dismantle and restore the flexible shells of the lower rus, the need to constantly monitor the operation of the filters due to the absence of difficulties in their operation in the winter.

thirty

35

40

Claims (1)

Invention Formula An installation for deironing groundwater, which includes an aeration device, a contact tank and slow filters with a water supply system and a drainage system for filtrate drainage, characterized in that, in order to simplify operation, the filters are mounted on each other, and the water supply system is designed as a gutter along the perimeter of the filter with a perforated diaphragm attached to the edge of the gutter. s Oh. x “) S 4i " I about 4D Isoo p Is “NI / mpzhodhz sho 3 0000 at / // “.. - .....; . /.  . ,,, I, FIG. I