RU2375311C2 - Device for reagentless water purification - module for intense aeration and degassing (miad) - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: device for reagentless water purification - module for intense aeration and degassing contains a reactor-tank 7, two injectors 4, 5, injector section 3, hydrocyclone 2 and fan 6. Reactor-tank 7 is a rectangular container with a bottom, lying at an angle to its largest vertical wall, and if fitted with level sensors. The air space ä above the water level in the reactor-tank should not be less than 0.2 metres, and faces of mixing chambers of the injectors are at a height h of not less than 0.5 metres above the water level in the reactor-tank 7. ^ EFFECT: cheap reagentless water purification. ^ 2 cl, 2 dwg

Description

The invention relates to the field of non-reagent water purification and can be used in domestic water supply for the purification of natural waters from iron, manganese and their compounds when producing water of more than the required quality.

In water treatment technology, two main methods of water purification are distinguished: reagent - using oxidizing agents (chlorine, chlorine dioxide, hypochloride, ozone, etc.) and reagent-free. Reagent-free water treatment is widely known in various fields of technology.

Degassing involves the removal of dissolved gases from the water, imparting an unpleasant aftertaste and smell to the water, or making it corrosive.

There are installations, for example, a diagram of a constructive cooling tower (p. 230, Fig. 85, a book by L.A. Kulsky, M.I. Bulava and others, “Design and Calculation of Water Treatment Plants”, Kiev, 1972), a diagram of a film degasser (p. 233, ibid.), the scheme of the bubbling degasser (p. 236, ibid.).

For a more rapid process of water degassing, it is necessary to maximize the contact surface of the water-air phases by passing through cooling towers and using degassers (p. 229, ibid.). Water sprinkling is carried out using special devices. In the simplest case, they are wooden boxes with holes, they are placed above the receiving tanks. The height of the water fall in such structures is taken within 2-3 m.

Water gushing is carried out in open reinforced concrete or concrete pools, over which water is sprayed with special nozzles. By means of nozzles, separate streams of water are sprayed and form “torches”, between which air flows. The rate of flow of water from the nozzles should be such as to ensure the longest time spent in the air and the best spraying effect. The amount of water sprayed per 1 m ^{2 of} the pool area is taken to be 1 m ³ / h. Design of spraying pools for gushing of water includes:

- selection of nozzle type depending on the pressure of the degassed water and the degree of its contamination with suspended solids;

- definition of the pool and its design;

- drawing up a layout of nozzles and distribution pipelines over the basin area;

- hydraulic calculation of pipelines.

Cooling towers, used in some cases for degassing, are divided into drip, film, and spray by the method of creating the air-water interface, and by the method of air movement - into tower and fan. The main parts of the tower are: an exhaust tower, a water distributor, an irrigation system and a collection tank. In drip cooling towers, water is distributed over the entire section using trays and gutters. In the bottoms of the latter there are a number of holes in which the tubes are inserted. Water flows through them onto the spray plates and then flows in the form of drops to a wooden irrigation device consisting of racks. In the film cooling towers, the irrigation system is formed of vertical solid wooden shields close to each other. Water flows down them in the form of a film towards the air stream. In spray towers, water is sprayed over the irrigation system using nozzles.

Fan cooling towers have forced blasting or air exhaustion. They are cylindrical tanks with a pallet and a holey false bottom, on which a nozzle of ceramic Rashig rings or wooden laths, the so-called chord nozzle, is placed. Water is supplied from above through a switchgear, air is blown from below by a fan: water is discharged through a hydraulic shutter. The dimensions of the fan cooling towers are much smaller compared to other types of cooling towers, and the performance is higher. Degassing apparatuses used in water treatment plants to remove dissolved gases from water can be of the following types: film, loaded with Rashig rings, lump nozzle or wooden chord, working in conditions of counterflow of water and air supplied by a fan;

- bubbling with a nozzle from Rashig rings or lump and air blower;

- vacuum with suction of vapors and gases by a vacuum pump, steam or water jet ejector.

Film degassers with a nozzle from Rashig rings are a type of fan cooling towers, they are used for deep removal of carbon dioxide and hydrogen sulfide from water, as well as for partial removal of carbon dioxide for deferrization of water. The same degassers with a wooden chord attachment are used in cases where the installation capacity does not exceed 150 m ³ / h.

Bubble degassers are used for deep removal of carbon dioxide in installations with a capacity of not more than 20 m ³ / h. Vacuum degassers with a nozzle from Rashig rings are used for deep (0.01-0.05 mg / L) or partial (0.3-0.5 mg / L) deoxygenation of water, as well as for the joint removal of carbon dioxide and oxygen.

Film degassers are cylindrical tanks, into the lower part of which air enters. Degassed water flows down to meet him. The nozzle is located on an intermediate bottom made of a hole sheet in the form of a welded frame made of corner steel. The diameter of the holes or the size of the slots in the bottom is 20 mm. The distance from the bottom of the degasser to the intermediate bottom should be 600 mm. A hydraulic shutter is arranged at the outlet of the degasser water, the height of which is 20% higher than the maximum pressure created by the fan. The water entering the degassing is distributed over the cross section of the apparatus using a distribution plate placed above the nozzle at a height of 150 mm. 48 nozzles for water drainage, rising 100 mm above the plate surface, and 8 nozzles for air outlet 400 mm high are strengthened in the stove. The nozzles for air outlet are equipped with reflective caps. The distance from the distribution plate to the degasser cover is taken to be 500 mm. The water supply is in the center of the cover. The diameter of the pipe for air exhaust is determined based on the air velocity in it 5-6 m / s.

As nozzles in degassers, Rashig rings of 25 × 25 × 3 mm (GOST 748-67), gravel and coke are used. Bubble-type degassers, depending on the residual concentration of the removed gas, can be single-section or two-section. In the latter case, water passes sequentially through both sections located one above the other. The necessary volume of the working part of the degasser in this case is divided equally between sections. The air entering the degasser is also divided into two equal flows and enters in parallel into each section. The height of the air space above the water layer in the sections should be at least 0.5 m.

The disadvantages of these devices:

- have significant overall dimensions and construction heights, which leads to additional costs for the construction of water treatment plants.

Currently, intensive aeration and degassing modules are used for water treatment, in which traditional water-air ejectors are used, in which a stream of liquid flowing out at a high speed from the nozzle nozzle ejects the surrounding gas and creates a vacuum in the receiving chamber (PC), which certainly contributes to desorption CO ₂ . In the mixing chamber (KS), an air mixture forms (air bubbles are distributed in a stream of water), in connection with which the latter loses its transparency and acquires a milky color.

As an oxidizing agent, atmospheric oxygen or an ozone-air mixture is used. Water treatment occurs as a result of the use of processes of throttling, cavitation, turbulent diffusion, evacuation and increasing the contact area of two media, air and water, which can significantly increase the rate of degassing and aeration in the module compared to traditional methods.

The above processes occur in the ejectors located in the ejector sections, and in the tank - reactor module intensive aeration and degassing.

The exhaust gas is removed by an exhaust fan. Treated water through the pumping station can be supplied to the filtration module for subsequent processing. The sediment accumulated in the reactor tank is periodically dumped into a septic tank or sump during operation.

The closest prototype in terms of features is a bubble column with a chord nozzle (p. 236, Fig. 89; authors L. A. Kulsky. M. N. Bulava and others “Design and calculation of water treatment plants, Kiev, 1972) .

The disadvantages of the device:

- has significant overall dimensions and construction heights, which leads to additional costs for the construction of wastewater treatment plants.

The task of the invention is the creation of an economical, non-reagent device for water treatment.

The problem is solved by creating a new device-design module of intensive aeration and degassing (hereinafter, MIAD), which uses the processes of throttling, cavitation, turbulent diffusion, evacuation and increasing the contact area of two media, air and water, which can significantly increase the rate of degassing and aeration compared to other traditional devices.

The essence of the proposed device for reagent-free water treatment - MIAD - is illustrated by the description of the invention and the drawings, where in Fig.1 the device contains:

- borehole pump, N1 (item 1);

- a hydrocyclone (item 2), which contains a drain pipe;

- ejector section (item 3);

- ejectors, E1 and E2 (pos. 4) and (pos. 5), which contain receiving chambers (PC);

- fan (pos. 6);

- tank reactor (item 7);

- emergency overflow (pos. 8);

- pressure switch, RD (item 9);

- H2 pump (working and spare, pos. 10);

- control panel (figure 2, 11);

- shut-off and control valves: BH1 (pos. 12, BH2 (pos. 13) - control valve, BH3 (pos. 14), BH4 (pos. 15), BH5 (pos. 16), BH6 (pos. 17), BH7 (pos. 18), BH8 (pos. 19) - stop valves and K01 (pos. 20) check valve.

The reactor tank is a rectangular tank, in the upper part of which there is an ejector section in which ejectors E1 to E2 are installed, an exhaust fan, in addition, the bottom of the reactor tank is located at an angle α to the largest vertical wall of the reactor tank, which helps to remove sediment accumulated in the reactor tank during operation, periodically in a septic tank or sump.

To create an air space with a height of at least t = 0.2 meters above the water level, the reactor tank has level sensors (not shown conventionally in the drawing), in addition, the location of the exit of the cut-out of the mixing chamber (KS), pos.21, ejectors E1 and E2 above the water level in the reactor tank should be at least h = 0.5 meters.

To expand the scope of the device for cleaning and disinfecting water (or other liquids), it can be equipped with an ozonizer and supply the ozone-air mixture through ejectors E1 and E2 into the airspace of the reactor tank.

MIAD device operates as follows.

Water for cleaning is supplied, for example, from the well with a H1 pump to a hydrocyclone, in which slag is removed (sand, solid particles). Solid particles in the hydrocyclone are released as a result of the centrifugal force arising from the tangential introduction of clarified water. During the operation of the hydrocyclone, the released solid particles are discharged through the drain pipe into the drainage. Next, water enters the ejectors E1 and E2, in which a stream of liquid flowing out at a high speed (about 25 m / s) from the nozzle nozzle ejects the surrounding gas and creates a vacuum in the receiving chamber (PC) of the ejectors E1 and E2, which, of course, promotes desorption of CO ₂ . The formation of a water-air mixture occurs in the mixing chamber (air bubbles are distributed in the water structure, in connection with which the latter loses its transparency and acquires a milky color).

The oxidizer in the module uses atmospheric oxygen or an ozone-air mixture.

Water treatment occurs as a result of the use of processes of throttling, cavitation, turbulent diffusion, evacuation and an increase in the contact area of two media, air and water, which can significantly increase the rate of degassing and aeration in MIAD compared to other devices.

Thus, the above processes occur in the ejectors located in the ejector sections and in the reactor tank of the intensive aeration and degassing module (MIAD), in addition, the process of microbubbles formation occurs in the MIAD, which occurs during the cavitation process by the collision of ejector water jets with the reactor water. The process of collapse of microbubbles proceeds simultaneously with the disinfection of water, since during the collapse (collapse) of microbubbles inside them an extreme temperature of about 1000 ° C occurs, and the spores of fungi and bacteria that are in the center of collapse of the bubble are destroyed.

The sediment accumulated in the reactor tank during operation is periodically discharged into a septic tank or sump.

The exhaust gas is removed by an exhaust fan (Fig. 1). The treated water through the pump H2 can be supplied to the filtration module for subsequent processing and then to the RCW for the consumer.

Claims (2)

1. The device is a non-reagent water purification by intensive aeration and degassing, containing a tank reactor, two ejectors and an ejector section, characterized in that it is additionally equipped with a hydrocyclone and a fan, and the ejector section is located in the upper part of the reactor tank, equipped with level sensors, representing a rectangular tank, and the bottom of the reactor tank is located at an angle α to its largest vertical wall, and the air space above the water level in the reactor tank should be at least 0.2 m, with a cut The mixing chambers of the ejectors are located at a height of at least 0.5 m above the water level in the reactor tank. 2. The device according to claim 1, characterized in that it can be equipped with an ozonizer.

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