EP1262720A2 - Degassing device for liquids in a closed or open circuit - Google Patents

Abstract

The bleed for a heating fluid circuit includes a bleed gas container (1) with a feed pipe (11) and a bleed (4) having a rotary suction pump (3) to aspire the fluid over suction stub (28) and with return flow into the circuit. The single feed pipe (11) of the circuit (13) extends into the bleed container from the pipe (11) which opens into the upper half of the container via an injector nozzle (2). The gas pipe (10) opens in a float (14) in the water tank (6).

Description

The invention relates to a device for degassing heating or cooling systems, in which water, oil or water with additives to freeze it prevent being used for heat transfer. In the fluid circuits These systems have dissolved gases, especially ambient air, and these promotes corrosion inside the pipes. To this harmful influence To prevent this, the gases are regularly removed from the circulatory fluid. This is achieved using a pressure level degasser, such as in Heating systems are used. The pressure stage degassing is based on the Principle that - the higher the pressure in a liquid - the more gas in it can be solved. Therefore, by lowering the pressure in the liquid medium degassing can be achieved.

EP 0'856'135 B1 describes a method and a device for degassing a liquid in an essentially closed system of a plant known. According to this patent, a circulation pump is used liquid to be degassed from the essentially closed system, by using a shut-off valve in the form of a solenoid valve in a degassing container is sucked in, on the underside of which flows into it and also flows out through a spout in the bottom and afterwards through the circulation pump to the closed system via a check valve is fed again. In the degassing tank, a cylindrical, standing one and degassing takes place at the top of the dome-shaped container due to the negative pressure built up by the circulation pump. To a vacuum to generate, the liquid supply is in with the circulation pump running the degassing tank is interrupted by closing a shut-off valve. The Circulation pump is switched off for a short time at certain time intervals to vent them. When the solenoid valve is opened again, the pressure in the Degassing container slightly above atmospheric pressure and this will the gas excreted above the liquid level at reduced pressure upwards via a valve unit at the upper end of the degassing container in the environment pushed out. It is called the rinsing process. After a maximum of 30 The solenoid valve closes again in seconds. To prevent fluid too quickly into the venting unit at the upper end of the degassing container arrives, there is a chicane below the corresponding valve unit in the Degassing tank installed, which has to flow around the gas. The Degassing is carried out continuously by running cycle after cycle. The Circulation pump itself is arranged on it by means of a separate one Degassing vessel degassed. This proves to be important, and every 4 until 10 minutes the circulation pump is switched off for a few seconds, which causes the Pressure in the degassing vessel increases and the collected gases are expelled become. Safe operation would not be possible without this degassing of the circulation pump guaranteed because it would run dry. From the regenerative pipe behind the Circulation pump leads from a line in the upper area of the Degassing container, in which the line opens via a spray nozzle. Through this Injection of already degassed liquid into the degassing tank achieved a very large additional degassing due to the spray effect. That too degassing water is whirled up and the spray effect is generated from the nozzle additionally an enlarged water surface. Thus, through these two Effects released the gases bound in the medium. This degassing process in vacuum is always the same length as the rinsing process. If the rinsing process medium, very quickly flows from the system back into the system Degassing tank and the gases released before are released via the breather pushed out.

This degassing device causes due to its large degassing vessel volume from 8 to 12 liters content not inconsiderable pressure fluctuations in the otherwise closed circuit system of a system, for example a heating system, which are very undesirable. The minimum size of the degassing tank such a system when using an integrated pressure maintenance station is about 4 liters. Because the liquid supply into the degassing vessel is intermittent valves are also required, which sometimes cause pressure surges and cause flow noises in the liquid circuit. If there is a leak Check valve on the breather gas is sucked in again, which leads to wrong Leads gas measurements. In addition, the operation of this device must be ongoing be regulated and controlled, which means that the circulation pump must be switched on and off be switched off and valves must be opened and closed, what all with a corresponding effort in control and Control devices must be accomplished.

For gas measurement and the control of the device based on it a system is often used, which comes after the vent Check valve is installed to suck air in the vacuum phase too prevent. An orifice is installed after the check valve. Between the Aperture and the check valve branches off an outlet on which an adjustable Pressure switch is mounted in the mbar range. This entire unit is on highest point of the degassing tank attached. Now there is gas from the degassing tank ejected, there is a minimal back pressure in front of the cover, until gas escapes into the atmosphere. This pressure is from the pressure switch registered and processed in electronics. Is the after a certain time If the gas emissions are too low, the device is switched off for 24 hours and then it starts measuring again. The check valve will leak, which can easily happen can, as soon as condensate is expelled with the gas, becomes too much Gas measured and the device no longer switches off. According to this system can otherwise only worked with a minimum degassing tank of 2 liters become. Because the quantities in an even smaller degassing container are too small If the gas is excreted, the pressure switch could no longer register this. However, the larger the degassing tank, the larger they are System pressure fluctuations that arise in the vacuum phase. This Fluctuations have to be compensated with additional devices.

It is therefore the object of the present invention to provide a device for degassing liquids in a closed or open circuit to create, which have the same degassing performance as that described above Device with a much smaller degassing that yields without Regulators in the intake and pressure lines, i.e. no solenoid valves, no pressure control valves, no throttle valves or orifices or baffles requires and with which a certain maximum gas content very easily and can be kept safely. Last but not least, it is also an object of the invention, one to create such a device for degassing liquids, which is constructive is simpler and therefore cheaper to manufacture, and the one increased Operational safety and service life guaranteed.

This object is achieved by a device for degassing liquids in a closed or open cycle consisting of one Degassing tank with a supply line and a breather and subsequent Gas line and a circulating pump for extracting medium via a suction port from the lower area of the degassing tank and Feed back into the cycle, and which is characterized by being the only one Supply line from the circuit to the degassing tank consists of one line, that in the upper half of the degassing tank via an injector nozzle in the Interior opens, and the gas pipe in an associated water tank adjacent to the top of a float vertically movably mounted therein empties.

Two preferred implementations of this device are as follows described in detail with reference to the drawings and their function is explained.

Figur 1:

Die schematische Darstellung der Vorrichtung in einer Variante ohne automatische Nachspeisung in den Wasserbehälter;

Figur 2:

Die schematische Darstellung der Vorrichtung in einer Variante mit automatischer Nachspeisung in den Wasserbehälter;

Figur 3:

Eine Planzeichnung der Vorrichtung gemäss dem Schema nach Figur 1 in einer Ansicht von der Seite her gesehen;

Figur 4:

Eine Ansicht des Entgasungsbehälters der Vorrichtung nach Figur 3 in besagter Figur 3 von links her gesehen;

Figur 5:

Den Schwimmer im Wasserbehälter und der mit ihm gebildete Kontaktschalter.

It shows:

Figure 1:

The schematic representation of the device in a variant without automatic make-up in the water tank;

Figure 2:

The schematic representation of the device in a variant with automatic make-up in the water tank;

Figure 3:

A plan drawing of the device according to the diagram of Figure 1 seen in a view from the side;

Figure 4:

A view of the degassing container of the device of Figure 3 in said Figure 3 seen from the left;

Figure 5:

The float in the water tank and the contact switch formed with it.

Figure 1 shows the essential elements of the device for its operation. The degassing container 1 has the shape of a lying cylinder, which here seen schematically from the side. A circulation pump 3 is in its drain line 12 installed. The feed line 11 leads from the circuit 13 through a dirt filter 5 and then via an injector 2 into the interior of the Degassing container 1, in its upper half. At the top of the degassing tank 1, the gas line 10 is connected to discharge the separated gases. It leads via the vent valve 4 into a water tank 6. In this Water tank 6, a float 14 is arranged with a contact switch 9. The water tank 6 is also equipped with an overflow pipe 15. As a result of evaporation, there is a loss of liquid in the water tank 6, so that water has to be refilled from time to time, which is done manually here has taken place.

Figure 2 shows the practically the same device, but also with an automatic make-up to compensate for water loss in the Water tank 6 due to evaporation. For this purpose there is a refill valve in the water tank 6 7 with float 36 attached to it. About this is at Required cold water from the mains line 8 in the water tank 6. In addition, this version with automatic water make-up is the water tank 6 via an additional connecting line 17 with integrated magnet 15 and check valve 16 connected to the degassing tank 1 to which also a manometer 18 is connected.

FIG. 3 shows a plan drawing of the device according to the diagram according to Figure 1 seen in a view from the side. The device is on a mounting plate 26 constructed. The circulation pump 3 is via rubber bearing 27 screwed to this mounting plate 26. Your suction port 28 is with the bottom of the cylindrical degassing container 1 connected. You can see the figure here 1 on the right side of the picture, end face 29 of the cylindrical degassing container 1, where the supply line 11 or suction line 11 in the degassing tank 1 is introduced. Is on top of fitting 21 in supply line 11 a manometer 19 is attached. This fitting 21 includes on the underside replaceable dirt filter 5 a. The pressure line 12 of the circulation pump 3 leads from the pump head 24 back into the circuit 13 of the system. The Pump head 24 is equipped with a pressure adjustment screw 25, so that the delivery pressure of pump 3 is adjustable. At the top of the degassing tank 1 a vent 4 is placed, at the upper end of which the gas line 10 is connected Check valve 22 is connected. This gas line 10 leads into the adjacent water tank 6 and there the gas pressure acts from above a float 14. This closes one with a float switch 9 Contact or interrupt depending on the. In the water tank 6 you can see also the overflow pipe 15. The level in this water tank 6 fluctuates in operation between the minimum and maximum shown. at Water should be refilled below the minimum, which is done manually here has to be done. The device is equipped with a control unit 23, which processes the signals of the contact switch 9 and accordingly the Pump 3 controls. In a particularly advantageous embodiment as shown in FIG. 2 water has been added, water is added automatically. This too Functions are then monitored and controlled by the control unit 23. On the other hand, if the level exceeds the maximum, then flows excess water through the overflow pipe 15 to the outside.

FIG. 4 shows a view of the degassing container 1 of the device 3, but in the position of the device shown in this figure 3 seen from the left. You can see the cylindrical degassing tank 1 from the side in a longitudinal section, so that the view inside is released. The peculiarity of the whole degassing device is that the Degassing can be carried out with such a compact degassing container 1, which as shown here is only 72mm in inner diameter and 190mm in length measures and has a content of only about 0.5 to 0.7 liters. To be efficient Degassing can be achieved with such a very small degassing tank 1 the shape and arrangement of the injector 2, and the placement of the Vent 4 of great importance. It is supposed to have a relatively large water surface should be present and when the liquid to be degassed is injected good swirling of the same can be achieved. To achieve this is in one horizontally arranged tubular container with end faces 29,30 on both sides one end face 29 above the central axis is an injection nozzle 2 built-in. It is important that the jet is injected from the injector nozzle Water is a concentrated, sharp, that is, a conical jet. The beam thereby bounces on the opposite wall 30 of the degassing container 1 on and does not capture the water in the degassing vessel 1 and spray it on a page. This would expose the suction nozzle of water and the The pump would even suck in air. The injection effect by bouncing the thin one Beam on the counter wall 30 causes the whole to whirl up Water surface 20 in the degassing tank 1. This impact on the Back wall 30 of the degassing container 1, the water parts are atomized, what leads to increased outgassing. It is very important to arrange the Outflow nozzle 37 to the breather 4. This must lightly over the injector 2 be offset to the rear so that its central axis is slightly behind the Nozzle orifice. As a result, the breather 4 becomes immediate due to the injector effect emptied if there is any water in it. This is also the one Area where, when filling the degassing container 1, an empty space until the end remains in which the gases collect and unhindered in the vent 4 reach. Only when the water flows in will the free gases pass over the Vent 4 eliminated.

This efficient degassing only creates a negative pressure in the tank of - 0.2 to -0.5 bar is required and nevertheless excellent outgassing reached. The pressure values for operation are on the pressure adjusting screw 25 adjustable. That the operation of this device with very little Vacuum comes additionally has the advantage that the pump 3 is not in comes a gravitational area and thereby remains spared. To the vacuum not to drop below -0.5 bar, this is done electronically by the Control unit 23 controlled. The vacuum is in the version with automatic water make-up by means of a pressure sensor and at Version without automatic make-up by means of a pressure switch 39 measured. When used with the pressure switch 39, the Pump generated vacuum is monitored by the pump after falling below - 0.5 bar is switched off with a time delay. There is a normal degassing cycle from a pump running time of 3.5 min. and a downtime of 1.5 min If the value falls below -0.5 bar, the pump switches off after 1.5 minutes. This time delay can be set in a menu of the control unit 23. at the version with the pressure sensor is switched off in stages. The trigger point is again a negative pressure. At a value of -0.5 bar one occurs first time-controlled period of max. 3.0 min runtime in effect until reached from -0.65 bar vacuum. However, if the pressure drops below -0.65 bar, one becomes second time control activated, which only has a maximum runtime of 1.5 Min. If the vacuum reaches a value of -0.8 bar, the pump 3 switched off immediately. These times are also in the menu of the control unit 23 adjustable. The control described has the advantage that with a poor basic setting of the vacuum, or if the set value changed, the device still runs optimally controlled.

The intake port 28 to the pump 3 is located exactly under the injection nozzle 2. This is so large that there is always plenty of water for it Pump 3 arrives, whereby dry-running protection is implemented. In the shown For example, the suction line 11 opens into the upper one via the injector nozzle 2 Half of the interior of the degassing tank 1. The liquid medium injected as shown and its jet hits the opposite end 30 of the degassing container 1. The deaerator is above the degassing container 1 4 arranged, from which the gas line 10 via a non-return valve in Form of a check valve 22 leads into the water tank 1.

In Figure 5 is the detailed structure of the float 14 in the water tank 6 shown. This part of the degassing unit takes over the function of Monitoring and registration of the gases expelled under pressure. Furthermore he monitors the water level in the water or make-up tank 6. The For this purpose, float 14 is on an inflow tube 31 for the gas to be inflated can be moved vertically with an anti-rotation pin 32 arranged parallel to it guided. The inflow pipe 31 and the anti-rotation bolt 32 are in one Holding plate 33 attached, which is mounted inside the water tank 6. On Reed switch 34 is also attached to the holding plate 33 and acts with one Permanent magnet 35 together on the top of the float 14th is mounted.

The gas-carrying inflow pipe 31 of the gas line 10 from the breather to Float switch is dimensioned so small, in the order of approx. 2.0mm diameter that the gases into the at a high speed Bottom bore 38 of the float 14 and this even with very small Push the gas quantities down. The float 14 will flow out approx. 1mm or more moved downwards, the reed switch registers this 34 and forwards its signal to a control unit 23, which it further processed. The second function of the float 14 is as follows: if the Float 14 no longer so far due to lack of water in the water tank 6 can rise to close the contact in the reed switch 34, is a Alarm condition caused. The one that is open when a make-up is due Solenoid valve is closed. This will suck air into the Degassing container 1 prevented. The alarm is also triggered if in the An error has occurred in the power supply. So with this system it is essential that there is always a certain water level in the vessel 6, namely, first to register the gas content precisely and second by one Sucking in air in the event of a defective backstop 22 in the breather 4 avoid.

The operation of this device is now explained in detail below and explains. The pump 3 with integrated pressure control promotes water from the Degassing container 1, which creates a negative pressure in this. Once a Pressure difference between the inside of the degassing container 1 and the System system has arisen, the water in the suction line 11 begins to flow the injection nozzle 2 into the degassing container 1. That through the Water flowing in after nozzle 2 reaches a high level as a result of nozzle 2 Speed and a beam effect is created. After Bernoulli's Flow law thus arises in the jet and also above the nozzle 2 stronger negative pressure that very quickly the vent 4 of any therein emptied existing water. Because more water comes out due to the pump performance the degassing container 1 is drawn off as water through the injection nozzle 2 flows in, creates a negative pressure in the degassing container 1 anyway Regulation on the pressure adjusting screw 25 on the pump head 24 becomes a uniform flow in the negative pressure of the water to be degassed achieved. The short overall length of the degassing container 1 causes the water jet collides with the inside of the end face 30, causing a strong swirl which creates water particles. In addition, when the water level drops Degassing container 1 the effect of the nozzle 2 to wear, about which not yet degassed water is injected. Due to the impact on the end face 30 the water particles are atomized, taking the gases out of the water be eliminated. This entire package of measures and effects increases the performance of the degassing and enables operation with a very small degassing tank 1 with a content of less than one as shown Liter. Even with this small degassing container 1 can be up to 5 minutes without Interrupt be degassed. Then the circulation pump 3 for 1½ minutes turned off to expel the released gas through the vent 4. The The nature of the circulation pump 3 leaves only a minimal backflow of Water too. This reflux is sufficient to remove any gases that are present have collected in the pump head 24, climb back into the degassing container 1 allow. However, the majority of the liquid flows after the Circulation pump 3 via the injection nozzle 2 into the degassing container 1 after what again causes an increase in pressure inside. As soon as a pressure increase of +0.01 bar in degassing tank 1 is exceeded, all free gases via the vent 4, the check valve 22 and the gas line 10 passed into the water tank 6. The over this gas line 10 in the Water container 6 flowing gases now act with the float 14 in Water tank 6 together. That under pressure and at increased speed escaping gas namely presses the float 14 in the container 6 below, provided the amount of gas is large enough. This movement of the float 14 is registered by means of the contact switch 9. The contact switch 9 remains closed for a long time, there is no degassing and the gas content in the Circuit 13 is therefore harmless. At the same time, the water supply prevents the float 14 and the mouth of the gas line 10 sucking air in the degassing tank 1, which would otherwise cause an incorrect gas measurement, if the check valve 22 leaks. The buoyancy of the float 14 is dependent on the height of the water level in the container 6, and this Buoyancy is used to determine the switch-off of the device. Sinks the level is far below, the buoyancy is reduced and even a small gas flow is off the gas line 10 is able to push the float 14 down and the Interrupt contact switch 9. The float 14 always remains complete submerged in water.

In the version with automatic water make-up there is a connecting line 17 with integrated solenoid valve 15 and a check valve 16 present between the water tank 6 and the degassing tank 1. Furthermore a refill valve 7 with float 36 is installed in the container 6, through which cold water flows in via line 8 from the mains line if required can. Thanks to the automatic water make-up, it is always the same Ensures water level in container 6, which ensures that the buoyancy the float 14 is always the same. The refill valve float 36 7 itself also has the additional function of monitoring the water level. If for any reason the water level drops below the minimum, will the make-up process and the degassing are interrupted. The same surveillance the device has no make-up when the water level falls below the minimum, for example due to evaporation.

With this gas routing system it is unimportant whether there is a leak Check valve 22 on the vent 4 about a small amount of water from the Water tank 6 is sucked in, or whether about condensed water through the breather 4 is eliminated with. Nevertheless, the gas measurement will always be correct. The most important feature of this degassing unit is that none Control elements such as solenoid valves, pressure control valves, throttle valves or Apertures are required for the function of degassing. The device is thus greatly simplified compared to the known solutions and also considerably compact. Its simple construction gives it a very high level of operational security, since none of the installed elements is susceptible to faults, and moreover the simple construction of course allows the device to be more cost effective than to manufacture existing solutions.

Claims (9)

Device for degassing liquids in a closed or open circuit (13), consisting of a degassing tank (1) with a feed line (11) and a vent (4) and adjoining gas line (10) and a circulating pump (3) for extracting Medium via a suction nozzle (28) from the lower region of the degassing container (3) and feeding it back into the circuit (13), characterized in that the only feed line (11) from the circuit (13) into the degassing container (1) from a line ( 11), which opens into the inside of the upper half of the degassing container (1) via an injector nozzle (2), and the gas line (10) in an associated water container (6) adjacent to the top of a float (14 ) flows out. Apparatus according to claim 1, characterized in that the degassing container (1) is formed by a horizontal cylinder with front sides (29,30), the volume of which is less than one liter, and that the injector nozzle (2) in the upper half of one front side (29) is installed and is directed towards the opposite front side (30), and that the suction nozzle (28) of the suction line (12) of the degassing container (1) from below the nozzle (2) through the cylinder wall from the degassing container (1) leads out and the gas line (10) from above the nozzle (2) through the cylinder wall out of this. Device according to one of the preceding claims, characterized in that the degassing container (1) forms a horizontal cylinder with an inner diameter of less than 100mm. Device according to one of the preceding claims, characterized in that the float (14) in the water tank (6) is mounted on a holding plate (33) by the gas-carrying inflow pipe (31) of the gas line (10) from the breather (4) to the float ( 14) leads into a vertical basic bore (38) of the float (14), and the holding plate (33) is equipped with a reed switch (34) with which the float (14) forms a contact switch (9), and that a programmable logic control unit (23) with menu and display is available, in which the signal of the contact switch (9) can be processed, so that a degassing cycle can be operated from an adjustable pump running time and pump downtime. Device according to one of the preceding claims, characterized in that the float (14) in the water tank (6) is mounted on a holding plate (33) which is equipped with a reed switch (34) with which the float (14) has a contact switch ( 9) forms in that there is a permanent magnet (35) on the top of the float (14) which interacts with the reed switch (34) which is arranged in the holding plate (33) of the float (14). Device according to one of the preceding claims, characterized in that in order to prevent the pressure in the degassing container (1) from rising or falling below the value of -0.5 bar, the programmable logic control unit (23) is connected to a pressure sensor in the degassing container (1), so that the pump (3) can be switched off after several time-controlled periods. Apparatus according to claim 6, characterized in that in order to prevent the pressure in the degassing container (1) from rising or falling below the value of -0.5 bar, the programmable logic control unit (23) is connected to a pressure sensor in the degassing container (1), so that one Value of -0.5 bar, a first time-controlled period can be activated, and when a negative pressure of -0.65 bar is reached, a second time control can be activated, and the pump (3) can be switched off after reaching -0.8 bar. Device according to one of claims 1 to 5, characterized in that in order to prevent the pressure in the degassing container (1) from rising or falling below the value of -0.5 bar, the pump can be switched off with a time delay after falling below -0.5 bar by means of a pressure switch (39) is. Device according to one of the preceding claims, characterized in that the circulation pump (3) has a pump head (24) with a pressure adjusting screw (25) and dirt filter (5).

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