RO135535A2 - Automatic siphoning installation - Google Patents

Abstract

The invention relates to an automatic siphoning installation to be used in the transfer of a liquid between two basins, a storage basin and a consumers' supply basin, located at different levels, where the influent conduit must pass, for natural reasons, over the level of the water in the storage basin from which the liquid is transferred. According to the invention, the installation comprises three basins (B1, B2 and B3), a storage basin, a consumers' supply basin and a filling and aeration basin, the latter having much lower capacity than the two other basins, the conduit path forming a siphon consisting of an upward conduit (1) and a downward conduit (2) which is longer than the upward conduit, the basins (B1 and B2) being at different levels, where the siphon principle is used for the transfer of liquids, which leads to significant reduction of electric power consumption, since the flow priming hydraulic pump (P) is only used for a short period of time, the other basin (B3) being placed at the top part of the siphon for aeration and filling of the upward and downward conduits (1 and 2), respectively, with liquid, the installation being provided with some lower level sensors (SNI1, SNI2 and SNI3) and some upper level sensors (SNS1, SNS2 and SNS3) for each of the said basins (B1, B2 and B3), a pressure sensor (SP), a flow meter (D) and four servo valves (SV1, SV2, SV3 and SV4) which make various connections between the conduits and the pump (P), the automatic operation of the claimed siphoning installation being thus enabled by a control system with a microcontroller or a programmable automaton.

Description

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The invention refers to a hydraulic installation that can be used to transfer a liquid (e.g. water) between two basins, the first one for accumulation and the second one for supplying consumers, located at different levels at which the route of the supply pipe must pass, due to natural causes, above the water level in the reservoir from which the liquid is transferred. Due to the fact that the storage and supply basins for consumers are at different levels, the siphon principle is used to transfer the liquid. The proposed installation has the role of transferring the liquid between two basins by achieving an important saving of electrical energy, since the hydraulic flow priming pump is used for a short period of time. The hydraulic system is connected between three basins: two base basins and one filling and venting basin of small capacity. The small capacity basin is mounted on the top of the hydraulic system and is used for filling with liquid and venting the pipes. The installation consists of two level sensors for each basin, a pressure sensor, a flow meter, four servo valves and a hydraulic pump. The control of the siphoning installation can be done with a microcontroller or programmable automaton.

The automatic siphoning installation can have various fields of use: at drinking water supply installations of localities; in mining operations;

other industrial branches;

in agriculture.

The principle of siphoning liquids has been applied for hundreds of years in all fields and is used to transfer liquid between two containers at different levels. Usually, hydraulic installations where the liquid is transported by siphoning are formed by a U-shaped tube, through which the liquid circulates without being pumped from one tank to another. Most siphons flow by gravity.

Over time, gravity traps have been built (US 149948, US 851688, US 892382, US 1499568, US 1610973, US 2124053, US 2560532, US 3090966, US 5133484, US 6359347 Bl, US 85244492 B , US 2009/0077902) or capillary (US 42238, US 4280658, US 6178984 Bl, US 2013/0192689 Al). Traps are known where priming can be done manually (US 149948, US 851688, US 892382, US 1610973, US 2124053, US 2560532, US 3090966, US 2013/0192689 Al, US 409071, US 659669) or automatically (US 149956 US 1083995, US 1524833, US 2184025, US 4124035), some siphons can operate at atmospheric pressure (US 149948, US 851688, US 892382, US 1610973, US 2124053, US 2560532, US 3090966, US 49246, US 49264, US 4906561 , US 2602463, US 2855860, US 4759857), under vacuum (US 8544492 B2, US 2010/0071780 Al, US 2012/0068367 Al) or under pressure (US 6359347 Bl, US 4280658, US 2602463). Siphons used in the chemical field are known, for the transfer between two containers of dangerous liquids (US 149948, US 1499568, US 2124053, US 1524833, US 6694889 B2) or for the separation of liquids (e.g. separating milk from cream) (US 851688 , US 1610973, US 2124053, US 1465207). Some construction solutions of siphons are composed of flexible pipes that can be strangled by special devices to preserve the water column of the siphon (US 2013/0192689 Al, US 659669, US 1465207), in others the siphon pipes can be rotated 180° ( US 851688), some have a special construction with additional tubes for priming the water column (US 892382, US 2184025), may have check valves (US 2560532, US 2009/0077902 Al, US 2602463), bellows in certain areas of pipes so that the siphon can be extended when a lever is actuated (US 3090966), some siphons can be made with several pipes connected in parallel on the ascending and descending branches (US 4124035), with coaxial pipes (US 5133484) or with z ' ' pipes of different diameters (US 2013/0192689 Al, US 903395), some siphons require priming pumps (US 5133484, US 1277772), others are used to collect water from the roofs of houses (US 2009/0077902 Al) and some siphons have included filters for liquids (ex. water) (US 4280658, US 6178984 Bl, US 4759857, US 5006264, US 6766817 B2, US 2004/0187919 Al).

The practical applications of siphons can be in various fields: chemical (US 149948, US 1499568, US 1610973, US 2124053, US 5133484, US 1524833, US 1465207, US 5006264), domestic water (e.g. toilets) (US 2560532, US 3090966), in the production of electricity (US 6359347 Bl, US 8544492 B2, US 2010/0071780 Al, US 2012/0068367 Al), in irrigation in agriculture (US 4223837, US 6178984 Bl, US 903395), in water supply installations drinking water of localities (US 1083995, US 2602463, US 2855860) and to automatic water collection (US 2009/0077902 Al).

The automatic siphoning installation, which is the object of the present invention, has the following advantages:

it is simple from a constructive point of view;

achieves an important electricity saving (95-99%) compared to the continuous use of the hydraulic pump when transferring the liquid between the two reservoirs;

uses the siphon principle;

it is reliable in operation.

The automatic siphoning installation shown in figure 1, according to the invention, ensures the transfer of the liquid (it is further considered that the liquid is water) between the accumulation basin Bl and the basin B2 for supplying consumers. in fig.l, the source of water supply of the accumulation basin Bl from where the water is to be transferred, nor the way of consuming the water from the reservoir B2, is not specified. in the reservoir Bl, from where the water is transferred, the level at a given moment is hl, and the minimum and maximum water levels are detected by the sensors SNI1 and SNS1. in the B2 consumer supply basin, where the water is transferred, the level at a given moment is h2, and the minimum and maximum water levels are detected by sensors SNI2 and SNS2. Filling the hydraulic system with water, to create the siphoning effect, is done from the B3 basin, with a much smaller capacity than the other two, which also has the role of venting the hydraulic system. in the filling and venting basin B3, the water level at a given time is h3, and the minimum and maximum levels are detected by sensors SNI3 and SNS3. When implementing the siphon principle, the upward pipe 1 of the siphon is shorter than the downward pipe 2 of the siphon. To detect the water column on the downpipe 2 of the hydraulic installation, a pressure sensor SP mounted at a height hp from the siphon elbow is used, and a flowmeter D is used to detect the water flow. When making the various connections in the hydraulic installation, four servos are used valves (SV1...SV4). Servovalves are made of ball valves with rotation between 0° and 90° actuated by SM electric servomotors which can be DC, AC electric motors. with reducer or stepper motors, where the rotor can be precisely positioned. To ensure the siphoning principle of the installation, especially when there is not a large difference in level between the Bl and B2 basins, it is important to use servo valves that have an extremely low pressure drop (theoretically zero). The servo valve SV1 introduces the hydraulic pump P into the system, the servo valve SV2 short-circuits the hydraulic pump P, the servo valve SV3 connects the filling and venting basin B3 to the hydraulic system, and the servo valve SV4 connects the downpipe 2 of the hydraulic system to the consumer water supply basin B2.

The configuration of the automatic siphoning plant is given in figure 1, and the logic diagram corresponding to the control plant made with a microcontroller or programmable automaton is shown in figure 2.

/ '

Initially, the four servo valves SV1...SV4 are closed. When starting the installation, it is checked if the water level in the B2 basin is below the minimum level, detected by the SNI2 sensor, and the presence of water in the storage tank Bl, detected by the maximum level sensor SNS1. If the maximum water level in the filling and venting basin B3, sensed by the maximum level sensor SNS3, is not reached, the servo valves SV1 and SV3 are opened, and the hydraulic pump P is started. Water is transferred from basin Bl to basin B3. Hydraulic pump P operates until the maximum level is reached in basin B3, level sensed by SNS3, after which servo valve SV1 is closed and hydraulic pump P is stopped. Servovalve SV3 being open allows water to enter the pipes of the hydraulic system to fill and vent them. After a period of time tl and when the pressure sensor SP detects constant pressure on the water column in the down pipe 2 of the hydraulic installation, the servo valve SV3 closes.

A repeatable procedure follows. Servo valves SV1 and SV4 are opened and hydraulic pump P is started. After a period of time t2 and after the flowmeter D mounted on the downpipe 2 senses a stable water flow, the servo valve SV1 closes and at the same time the servo valve SV2 opens and the hydraulic pump P is stopped. at this moment, the water flows by gravity, without pumping (saving electricity), from the storage basin Bl to the consumer supply basin B2 due to the siphoning effect through the servo valve SV2, the ascending pipe 1, the descending pipe 2, the flow meter D and servo valve SV4. If during the passage of water from basin Bl to basin B2 the flow meter D senses an intermittent flow (a rapidly varying water flow), the servo valve SV2 closes, and at the same time the servo valve SV1 opens and the hydraulic pump P is started. After a period of time and after the flow meter D detects a stable water flow, the servo valve SV1 closes and at the same time the servo valve SV2 opens and the hydraulic pump P is stopped. The siphoning process is carried out again. This procedure is repeated whenever the flowmeter D detects an intermittent flow of water.

If the water level in basin B2 has reached the maximum level, sensed by the sensor SNS2, the servo valves SV2 and SV4 are closed and the water supply to basin B2 is stopped. Upon a new emptying of the B2 storage tank, level sensed by the SNI2 sensor, the entire filling process is resumed.

The control system, in addition to the control itself, warns optically or on the display of the minimum or maximum level of the three basins, the status of the pressure sensor, the flowmeter, the status of the four servo valves and the hydraulic pump.

in figure 1 the meaning of the terms used is as follows:

- for lower level sensors SNI = 0: the water has dropped below the lower level;

- for lower level sensors SNI = 1: the water level is equal to or higher than the lower level;

- for higher level sensors SNS = 1: the water has reached the upper level;

- for upper level sensors SNS = 0: the water is below the upper level;

- for servovalves SV = 0: they are closed and water does not pass;

- for servovalves SV = 1: they are open and water passes;

- for the hydraulic pump P = 0: the hydraulic pump is off;

- for the hydraulic pump P = 1: the hydraulic pump is switched on;

- for the pressure sensor SP = 1: the pressure corresponding to the water column with the height hp in pipe 2 of the installation was determined;

- for the flow meter D = 1: the water has the normal flow, without rapid variations.

The stable flow of water through the pipes and the siphon height hb depends on the atmospheric pressure, the level difference hc between the basins Bl and B2, the diameter of the pipe, the porosity of the pipe, the viscosity of the liquid and the hydraulic losses (in bends, tees, servo valves, flow meter) . under certain conditions, it is possible that after venting and filling ^{3 c} correctly with water of the ascending 1 and descending pipes 2 of the siphon, the servo valves SV2 and SV4 can be opened directly, without using the hydraulic pump P.

......

Claims (2)

demand 1. Hydraulic control unit characterized in that it uses siphoning to transfer a liquid between two storage tanks B1 and supply B2. Initially, the four SV1 ... SV4 servo valves are closed. At the start of the installation, it is checked whether the liquid level in the B2 supply tank for consumers is the minimum, detected by the SNI2 sensor and the presence of the liquid in the storage tank Bl, notified by the maximum level sensor SNS1. If the maximum level in the filling and venting tank B3, detected by the maximum level sensor SNS3, is not reached, the servo valves SV1 and SV3 are opened and the hydraulic pump P is switched on. The liquid is transferred from basin B1 to basin B3. The hydraulic pump P operates until the maximum level in basin B3 is reached, a level detected by SNS3, after which the servoventils SV1 and SV3 are closed and the hydraulic pump P is switched off. The SV3 fan valve is open for venting and filling pipes 1 and 2 of the hydraulic system. After a period of time in which the pressure sensor SP detects constant pressure on the downspout 2 of the hydraulic system, the SV3 valve closes. A repeatable procedure follows. After a time tl, the servo valves SV1 and SV4 open and the hydraulic pump P is switched on. After a period of time t2 and after the flow meter D mounted on the downstream pipe 2 detects a stable flow of liquid, the servoventil SV1 closes and, at the same time, the servoventil SV2 opens and the hydraulic pump P is stopped. At this point, the liquid flows gravitationally, without pumping, from the storage tank B1 into the supply tank of consumers B2 due to the siphoning effect, through the servoventil SV2, the ascending pipe 1, the descending pipe 2, the flow meter D and the servoventil SV4. If during the passage of the liquid from the basin Bl to the basin B2 the flow meter D detects an intermittent flow (a rapidly variable liquid flow), the servo valve SV2 closes, and at the same time the servo valve SV1 opens and the hydraulic pump P is started. After a period of time and after the flow meter D detects a stable flow of liquid, the servo valve SV1 closes and at the same time the servo valve SV2 opens and the hydraulic pump P is stopped. The creasing process is performed again. This procedure is repeated whenever flow meter D detects an intermittent flow of liquid. If the level of the liquid in basin B2 has reached the maximum value, detected by the sensor SNS2, the servo valves SV1 and SV4 are closed and the liquid is no longer transferred to the basin B2. Upon re-emptying the B2 tank, the level detected by the SNI2 level sensor, the entire filling process is resumed. 2. The B3 filling and venting tank, characterized in that it is mounted at the highest level of the hydraulic system, being used both for filling and venting the riser 1 and sink 2 of the siphon. In this way, after the operation of the hydraulic pump P, the siphoning effect is effectively achieved.