SK5462001A3 - System for vertically aerating and/or mixing liquids - Google Patents

Abstract

The system is designed for vertically aerating and/or mixing liquids in their treatment installations and, in particular, in sewage treatment plants. To this end, the inventive system has a float (8), which supports itself on the surface of the aerated and/or mixed fluid and which is connected to a bell-shaped body (7) that is open at the bottom. The supporting body (9) and the submersible electric motor (1) that comprises the shaft are placed inside the bell-shaped body (7). The impeller equipped with axial blades (2) is located on said shaft. Inside the supporting body (9) of the system are the outer casing, which is vertically flown through and which comprises the guide blades (3), and at least one air induction pipe (6), which comprises at least one mixing chamber for liquid and air (5). The outer casing and the air induction pipe are mounted inside the supporting body (9) in such a manner that the supporting body (9) of the system connects the space behind the guide blades (3) via the nozzle (4) to the opening of the air induction pipe (6) and to the opening of the mixing chamber for liquid and air (5).

Description

Technical field

The invention relates to a device for vertically aerating and / or mixing liquids, i. j. water purification and treatment facilities for environmental protection, stagnant water oxygenation in reservoirs, ponds and dams, as well as gas dissolution in liquids.

BACKGROUND OF THE INVENTION

Current devices use a method resulting from their mechanical or pneumatic principle for aerating liquids.

Mechanical devices ensure the aeration of liquids by the flow of liquid through the diagonal or radial wheel. There are known devices for aerating liquids with a diagonal wheel which is partially submerged in a liquid and which, in rotation, transports the liquid through a closed diagonal channel above the liquid surface where it sprays it and mixes it with air.

A disadvantage of the operation of such devices is the presence of nebula and aerosols, which arise when the liquid is sprayed in the air, which in the case of chemicals or contaminated liquid causes hygienic defects in their surroundings. Also, such devices are characterized by frequent failure and low oxygen recovery from the air.

Other mechanical devices provide for the aeration of liquids by a radial wheel which is submerged at the bottom of the tank in the liquid and which in rotation rotates the liquid in the radial direction. The liquid to be conveyed thereby forms a suction effect in the stator of the device by means of which air is supplied through the air ducts above the liquid level, then the air is mixed with the liquid and then forced through the channels installed on the stator housing of the device into the liquid.

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A disadvantage of such devices is the need to install them at the bottom of the liquid tank in order to ensure efficient mixing of the liquid. This, however, results in high energy requirements for air intake and so-called air intake.

flow stacks formed by the discharge of a mixture of liquid and air through radial channels immovably mounted on their stator.

Other mechanical devices provide for aeration of liquids by means of an ejector to which a fluid is conveyed by a radial pump, generating a negative pressure in the ejector through the ejector, which ensures the suction of air through the air duct above the liquid level.

A disadvantage of the way of operation of such devices is the required higher speed of liquid flow in the ejector ensuring air intake and their low efficiency due to losses of the flowing liquid in the ejector and due to the formation of so-called. flow stacks formed by the discharge of a mixture of liquid and air from the ejector.

The mechanical device according to utility model CZ no. 10103 and CZ PV 1988-2787 where aeration is carried out by a propeller pump whose impeller is fixed to the bottom of the vertical hollow shaft. The hollow shaft has openings with a grille in the upper part for forced air or gas supply and in the lower part at the blades of the spiral-shaped impeller increasing in thickness tangentially towards the outlet edge, where it is scattered in the form of bubbles by rotating the blades equipped with another grating. then escape to her surface. In this case, the impeller is mounted in a coaxially vertically arranged tubular diffuser in a coaxial direction and, depending on the direction of rotation thereof, it is possible to change the direction of fluid flow in the tubular diffuser. In this case, when the air or gas supply is switched off, the device operates in the tubular diffuser as a conventional fluid flow mixer and, when the compressed air or gas is switched on, as its aerator.

The disadvantage of such a solution is the high cost of the source of compressed air as well as the distribution of compressed air, the necessity of using a powerful motor ensuring pumping of a large volume of liquid in the narrow tubular bore of the diffuser both during mixing and aerating the liquid.

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A solution according to WO 97/11772 is also known where the motor is mounted in a watertight chamber which functions as a float and at the same time as a mixed fluid flow baffle, the motor driving the impeller immersed perpendicularly or obliquely into the liquid. In this case, the device can be equipped with a supply of compressed gas leading to the impeller and at the same time the impeller can be placed between the obliquely expanding plates fixed to the waterproof chamber, possibly also in the guide plates opening above the surface. The waterproof chamber can be equipped with blades and serve as a large impeller. When the compressed gas supply is switched off, the device functions as a conventional liquid stirrer flowing towards the bottom thereof, and when the compressed air supply is switched on, it acts as an aerator for the liquid flowing in the same direction.

The disadvantage of such a solution is the high cost of the compressed air source, the high cost of the compressed air distribution, the overflow of the large liquid resistance arising during the rotation of the impeller blades in the liquid between the expanding waterproofing plate, the diffusion of air in the aerating liquid, high complexity, costly and costly during operation. Another variant of this solution sprays the mixed or aerated liquid by spraying above its surface, creating a nebula and aerosols, which in the case of chemicals or contaminated liquid causes hygienic harmfulness in their vicinity.

A solution according to U.S. Pat. No. 5,454,986, which consists of a mixing tank with a semi-annular bottom positioned deeper than the bottom of the center of the tank. Above the raised center of the tank bottom there is an impeller connected to the shaft and the engine. The engine is located above the surface. Compressed air is supplied to the impeller, which is entrained by the flow of liquid towards the semicircular bottom. The liquid stream forms the impeller of the liquid to be aerated.

The disadvantage of the solution is that it requires a tank with a demanding and expensive construction and the fact that this solution is designed for small tank volumes.

Pneumatic devices for the aeration of liquids mainly consist of a source of compressed air, most often a blower, aeration membranes ensuring the distribution of compressed air into small bubbles and compressed air transport lines from the compressed air source to the aeration membranes.

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A disadvantage of the way pneumatic fluid aeration devices operate is that they require the use of noisy compressed air sources with an expensive building object, the construction of complicated compressed air ducts and the emptying of the tank when installing the aeration membranes. The technical complexity of such devices causes frequent failure of the aeration membranes due to the clogging of small openings separating the conveyed air into small bubbles or air bubbles. ensuring that the air flow is constantly ruptured during operation. For these reasons, these devices require high investment costs.

A common disadvantage of the aforementioned devices operating on their principle is that they are not usable for mixing liquid without mixing with air and therefore, in the need of alternating mixing of the liquid without air and air, it is necessary to use two dedicated devices with separate liquid chambers interconnected piping with suitable fittings making them technically complex and economically expensive.

A device for aerating and / or mixing liquids according to utility model SK no. from. 2841 (DE 0143-2000), wherein the method of aerating and / or mixing liquids directly results from its operation. The device has an electric motor installed above the surface of the liquid, which rotates the impeller with axial vanes and which transports the liquid vertically from the bottom of the tank through the suction nozzle, guide vanes and transport channel to the mixing wheel in which the liquid creates a vacuum in the suction slot. whereby the intake air is sucked through the intake manifold and mixed with the liquid. The resulting mixture of liquid and air bubbles is then conveyed through the guide vanes in a horizontal direction to the tank, whereby the curvature of the guide vanes gives the mixing wheel rotation. The device is installed on a carrier float that floats at the liquid surface and keeps the device at a constant depth below the liquid surface range from 0.1 m to 5.0 m.

The disadvantage of the method of operation of this device is that the electric motor is installed above the surface, which increases the design dimensions of the whole device, its weight and the requirements for fitting its rotating parts. Another major disadvantage is the use of a combination of vertical fluid flow and its redirection to the horizontal direction, which increases hydraulic losses in such a method of aerating and / or mixing liquids, as the horizontal direction of the mixture outlet. i 1 · :::: :·· · ·: · · ..... ........

liquid and air bubbles significantly reduces the use of dynamic energy of the liquid-air mixture.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are largely eliminated by the vertical aeration and / or mixing apparatus of the present invention comprising a float, a submersible electric motor, an impeller with axial blades, an outer casing with guide vanes, air intake manifolds, liquid-air mixing chambers and a bell-shaped body. The body of which is based on the fact that on the surface of the aerated and / or mixed liquid there is a support float connected to a bottom-open bell-shaped body in which the support body is mounted, a submersible electric motor with a shaft on which the impeller with axial blades. In addition, a vertically flowing outer casing with guide vanes and at least one air intake manifold with at least one liquid-air mixing chamber are arranged in the apparatus support body so that the apparatus carrier interconnects the space behind the guide vanes, via a nozzle, with an air intake opening and through the liquid-air mixing chamber.

Preferably, the axis of the liquid-air mixing chamber is 0 to 60 degrees from the vertical axis of the submersible electric motor and / or the nozzle of the device is located below the surface of the aerated and / or mixed liquid at a depth of 0.1 to 5 m.

The greatest advantage of the vertical aeration and / or mixing of liquids according to the invention is that the low speed and large flow rate of the liquid ensures better utilization of the electric motor energy which is transmitted to the liquid by the impeller with axial blades, thereby ensuring suction of the required amount of air.

A further advantage of the present invention is that increasing the performance of such devices is directly dependent, in particular, on the mass flow rate of the liquid, for which the impeller with axial blades requires minimal energy. It is also an advantage of the vertical aeration and / or mixing of liquids according to the invention that the air-liquid mixture flowing out of its mixing chambers is directed in the liquid from the vertical liquid flow, in the liquid tank, by the mixing chambers in the liquid.

- 6 ········· · 0 · 60 degrees, allowing greater utilization of the dynamic energy of the liquid-air mixture as well as gradual destruction of the liquid-air mixture while minimizing formation called. thus achieving up to three times the oxygen utilization from the air, or up to three times its transfer into the aerated liquid compared to the prior art.

Overview of the figures in the drawing

FIG. 1 is a schematic illustration of an example of a device for vertically aerating and / or mixing liquids in a cross-section located in a liquid tank according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The device for vertical aeration and / or mixing of liquids according to the invention shown in Fig. 1 consists of a float of submersible electric motor 1, impeller with axial blades 2, outer casing with guide vanes 3 * a pair of air intake ducts 6, a pair of air mixing chambers 5 with the liquid and the bell-shaped body 7 as well as the support body 9, wherein the illustrated device is located in the tank 10.

On the surface of the aerated and / or mixed liquid, in the tank 10 is placed a carrier float 8 connected from below by an open bell-shaped body 8 in which the carrier body 9 of the device is mounted. In this case, a submersible electric motor 1 is mounted on the rotating shaft of which the impeller with axial blades 2 is mounted in the machine support body 9. At the same time, the outer casing with the distributing vanes 3, the air intake manifolds 6 and the of the liquid-air mixing chambers 5 such that the device support body 9 interconnects the space behind the guide vanes 3, through the nozzle 4, with the air intake duct 6 and the liquid-air mixing chamber 5. The axis of the liquid-air mixing chamber 5 clamps from the vertical axis of the submersible electric motor 10 to 60 degrees.

The apparatus for aerating and / or mixing liquids according to the invention shown in Fig. 1 is located at the liquid level in the tank 10 on the carrier.

- float 8 so as to have a nozzle 4 disposed in the device support body 9 below the level of aerated and / or mixed liquid at a depth of 0.1 to 5 m. After actuation of the submersible electric motor 1, the impeller with axial vanes 2 is rotated by the drive shaft, which immediately transports liquid inside the bottom open bell-shaped body 7 in a vertical direction with respect to the axis of the submersible motor 1 through the vertically flowing outer casing with guide vanes 3. After the nozzle 4, the dynamic effect of the liquid jet generates a vacuum which, under certain commonly known hydraulic conditions, spontaneously sucks air through the air suction line 6, which is subsequently mixed with the liquid in the liquid-air mixing chambers 5. Furthermore, such a mixture of air and liquid flows below 0 to 60 degrees of angle through the opening in the mixing chambers 5 into the liquid in the tank 10, where it is gradually dispersed in the liquid and the air continuously escapes therefrom into the atmosphere. After the rotational speed of the submersible motor 1 has dropped so that the negative pressure behind the nozzle 4, generated by the dynamic effect of the liquid stream, does not create sufficient conditions for the air to be sucked in by the air intake manifold 6 of the air device. by reducing the rotation speed from 99 to 15% of the operating mode for aerating liquids or at opposite speeds of the submersible electric motor 1 as suitable for aerating liquids, the vertical device according to the invention fulfills only the function of mixing the liquid in the absence of air. By such a speed control of the submersible motor 1, the vertical device according to the invention fulfills the function of aeration and / or, if necessary, mixing of the liquid without the access of air, in one tank 10.

The apparatus described and illustrated is not the only possible embodiment of the method for vertical aeration and / or mixing of liquids according to the invention, since another embodiment of the apparatus may have one or more than two air intake ducts or one or more than two air-mixing chambers of which the axis may be at any angle within the range of 0 to 60 degrees from the vertical axis of the submersible motor, wherein the number of air intake ducts may be different from the number of mixing chambers and the individual mixing chambers may have different angles to the vertical axis of the submersible electric motor. Further, the mixing chambers may rotate around the axis of the submersible motor during operation of the apparatus. Also, mixing of air with liquid can be forced through control valves (not shown). The float can be connected to the bottom-open bell-shaped body via the air intake duct, and the support body can be mounted in the bell-shaped body of the device in another alternative known manner. The devices according to the invention can also operate in large tanks such as e.g. in ponds, dams, etc., or on river flows.

Industrial usability

Vertical aeration and / or mixing of liquids can be used where the liquid needs to be aerated and thereby enriched with oxygen and / or mixed, for example in surface, ground and waste water treatment, water treatment and the like, especially in agriculture, food, chemical and other industries.

Claims (3)

PATENT CLAIMS • · · · · · · · · · · · 1. Apparatus for vertically aerating and / or mixing liquids, comprising a float, a submersible motor, an impeller with axial blades, an outer casing with guide vanes, air intake ducts, liquid air mixing chambers, a bell-shaped body and a supporting body, characterized by that on the surface of the aerated and / or mixed liquid there is a supporting float (8) connected to a bottom-open bell-shaped body (7), in which is mounted the supporting body (9) of the device and submersible electric motor (1) with shaft an impeller with axial vanes (2), wherein a vertically flowing outer casing with guide vanes (3) and at least one air intake manifold (6) with at least one liquid-air mixing chamber (5) are also disposed in the support body (9) of the device so that the device support body (9) interconnects the space behind the guide vanes (3) through the nozzles u (4), with an air intake duct (6) opening and a liquid-air mixing chamber (5) opening. Apparatus according to claim 1, characterized in that the axis of the liquid-air mixing chamber (5) clamps from 0 to 60 degrees from the vertical axis of the submersible electric motor (1). Device according to claim 1 or 2, characterized in that the nozzle (4) of the device is located below the surface of the aerated and / or mixed liquid at a depth of 0.1 to 5 m.