Patent Application
20110100032
The present invention relates to processing different gases and in particular to removing a first gas from a system comprising a second different gas.
One example for a system comprising a certain gas is an evaporator of a heat pump. In a heat pump, an operating liquid is transformed to an operating vapor by a respective combination of pressure and temperature. Therefore, in many cases, a synthetic fluid is used as operating liquid. However, heat pumps exist operating with water as operating liquid, such as shown in W2007/118482. In such heat pumps with water as operating liquid, e.g. ground water, seawater or also water circulating in a cycle, which is heated, for example, by an earth collector or an earth borer, is vaporized at a temperature of, e.g. 12° C., typically at a small pressure. The water vapor having such a low temperature present at a low pressure is compressed by means of a compressor, whereby both temperature and pressure are increased. The warm compressed water vapor will then be transformed to water again in a liquefier. Here, the operating liquid is heated up in the liquefier, wherein this energy can then be supplied to a heating cycle, such as a heating of a building.
It has been found out that the efficiency of a heat pump is highest when the evaporator actually exclusively contains the desired vapor or the desired gas, which has desired specific requirements with regard to a specific pressure/temperature ratio. If the heat pump is operated with a different operating fluid than water, the best efficiency will only result when actually only vapor of exactly this operating liquid is present in the evaporator. There is a similar situation when water is used as operating fluid. In this case, the efficient heat pump will be best when merely water vapor exists in the evaporator. The penetration of “foreign gases”, which can take place in any way, is hence unfavorable for the efficiency of the heat pump and should thus be reduced or completely prevented.
One option for minimizing the penetration of foreign gases is, for example, to operate the heat pump under a vacuum. This is associated with corresponding difficulties regarding technical practicability, which can be solved but, however, cause high financial effort. The penetration of foreign gases, however, cannot be completely prevented, even when a high effort is made. There are gaskets or other plastic materials that can age and become porous. Above this, a general diffusion of gases across materials exists, even when the materials themselves are watertight.
Hence, the effort for avoiding penetration of foreign gases can be increased arbitrarily, and it can still not be completely avoided that foreign gases penetrate. Hence, as a second problem, there is the question how foreign gases are to be dealt with when they exist within the system. Then, the foreign gases have to be brought out of the evaporator again somehow. For example, the foreign gases could be collected and pumped off the system. Since, however, heat pumps are often operated in that manner that the pressure in the evaporator differs heavily from the atmospheric pressure, pumping off the foreign gases from a system takes place from a low to a high pressure. If, for example, a heat pump operating with water as operating liquid is considered, the case can occur that foreign gases will have a pressure of 10 mbar and have to be pumped off against an atmospheric pressure of 1 bar. It is obvious that very powerful pumps are necessitated for this, which will have to handle only a small discharge amount but have to overcome an extremely high-pressure difference.
Hence, in heat pumps where high pressure differences exist between the operating pressure in the evaporator and the atmospheric pressure, which means the pressure outside the system, on the one hand, avoiding penetration of foreign gases is problematic, and, on the other hand, removing foreign gases from the system once they have penetrated is also very expensive and hence costly.
On the other hand, considering the high prices for fossil fuels, the market for heat pumps increases more and more. This has the effect that the competition on this market has increased. Since an important part of the market for heat pumps exists in the field of private house owners, who are frequently extremely price-conscious, the final price at which a heat pump system can be offered is a factor not to be underestimated regarding whether a heat pump can hold up on the market or not.
According to an embodiment, an apparatus for removing a first gas from a system having a second different gas may have: a collecting basin for collecting the first gas, the collecting basin having: a variable inlet opening for letting in the first gas into the collecting basin, wherein the inlet opening can be brought into communication with the system; a variable outlet opening for letting out the first gas from the collecting basin, wherein the variable outlet opening is not in communication with the system; and a means for generating a pressure in the collecting basin that is higher than the pressure of an atmosphere outside the variable outlet opening; the inlet opening and the outlet opening being implemented such that in a discharge mode, at a pressure in the collecting basin that is higher than the pressure in the atmosphere, the inlet opening has a higher fluid resistance than the outlet opening, such that the second gas can be output from the collecting basin via the outlet opening, and that in a collecting mode the outlet opening has a higher fluid resistance than the inlet opening.
According to another embodiment, a system for vaporizing may have: an evaporator cover that is implemented to maintain a pressure within the system that is smaller than a pressure outside the system; an inventive apparatus for removing, wherein the inlet opening of the collecting basin is arranged such that the inlet opening communicates with an evaporator region within the evaporator cover.
According to another embodiment, a heat pump may have: an evaporator having an inventive system for vaporizing; a compressor coupled to the evaporator for compressing vapor generated by the evaporator; and a liquefier coupled to the compressor for obtaining compressed vapor.
According to another embodiment, a liquefier may have: a liquefier region where a first gas and, as a second gas, a gaseous operating fluid to be liquefied exists, and an inventive apparatus for removing the first gas
According to another embodiment a method for removing a first gas from a system having a second different gas may have the steps of: in a collection mode, collecting the first gas; in a discharge mode, discharging the first gas from the collecting basin into an atmosphere outside the system; and in response to an event, increasing the pressure within the collecting basin by introducing the second gas into the collecting basin; wherein in the collecting mode the inlet opening has a lower fluid resistance than the outlet opening, and wherein in the discharge mode the inlet opening has a higher fluid resistance than the outlet opening.
Another embodiment may have a computer program having a program code for performing the inventive method when the method runs on a computer.
The present invention is based on the knowledge that by a specific design of the inlet opening and the outlet opening of a chamber basin for the foreign gas, which are implemented in a variable manner, and by providing a specific means for generating a pressure in the collecting basin such that the pressure is increased by generating the second gas within the collecting basin, an efficient and robust measure for removing foreign gases from a system is obtained. By closing the inlet opening for the foreign gas at a pressure in the collecting basin that is higher than the pressure in the system, and then, typically, opening the same at an even higher pressure, these foreign gases are discharged from the collecting basin. This “discharge” of the foreign gases takes place by means of the second gas generated by the means for generating the pressure, wherein the second gas is the same gas that primarily fills the system.
Hence, the foreign gas is trapped within the collecting basin. Then, when the collecting basin is to be emptied, the inlet opening is closed. Then, the pressure in the collecting basin is increased by generating the second gas within the collecting basin, until the outlet opening is opened. Then, the collecting basin is actually “flushed free” by means of the second gas, wherein this “flushing out” is the more efficient and faster the higher the pressure in the collecting basin is in comparison to the atmospheric pressure, such that when the outlet opening opens, fast pressure relaxation from the collecting basin to the atmosphere takes place. When the pressure in the collecting basin has dropped to a value that is typically still higher than the atmospheric pressure, the outlet opening will be closed again and the inlet opening can be opened.
The remaining pressure existing in the collecting basin is compensated with regard to the system by outputting the second gas, which has been generated by the means for generating the pressure and that has not yet been discharged towards the atmosphere but has remained in the collecting basin, into the system itself as vapor. This, however, is not problematic, since the second gas presents no foreign gas with regard to the operating gas in the evaporator, but is the “desired gas” itself. Relaxing the collecting basin into the vaporizing space, which is necessitated in order to prepare the collecting basin again for receiving foreign gas, presents a process, which is not harmful for the general evaporation process in the evaporator, but cooperates with the same. The water vapor output from the collecting basin to the evaporator, after a discharge process has taken place, supports the evaporation process, which runs in parallel anyway. This is also advantageous in that the still existing energy released by relaxation is not output to the atmosphere but remains in the process itself.
In particular within an application in a heat pump this is a great advantage, since there is the effort to keep the internal losses in the heat pump as low as possible for obtaining a minimum ratio of spent electric energy to extracted thermal energy.
Embodiments of the present invention will be detailed subsequently referring to the appended drawings, in which:
a is a sketch for illustrating the functionality of the apparatus for removing a gas of
b is a detailed illustration of the apparatus for removing a gas of
Further, the apparatus for removing the foreign gas comprises a means 1 for generating a pressure in the collecting basin, which is higher than the pressure in the system 2. In particular, the means 1 for generating the pressure is implemented to increase the pressure in the collecting basin by generating the second gas, which means the useful gas, in the collecting basin.
In an embodiment, which will be discussed below, the means 1 for generating the pressure includes a heater arranged in a liquid, which exists in the collecting basin 10, which presents, when the same is vaporized, the second gas, which means the useful gas. The means 1 for generating the pressure is coupled to a control 9. Depending on the implementation, the control 9 is implemented to activate the means 1 for generating the pressure periodically, depending on certain events or a certain determined or non-determined strategy. Further, the control 9 has to be implemented to actively control the outlet opening 4 and the inlet opening 5, as illustrated by the dotted control lines in
Hence, the apparatus for removing the first gas from the system has a discharge mode in which the inlet opening is closed and the outlet opening is open. It should be noted that the openings do not have to be opened or closed completely. Instead, it can be sufficient that the inlet opening has a higher fluid resistance than the outlet opening when the discharge mode occurs. The situation is similar in the collecting mode. In the collecting mode, the inlet opening can be open and the outlet can be closed. Here, also, not necessarily complete states have to prevail. It can also be sufficient that, in the collecting mode, the outlet opening has a higher fluid resistance than the inlet opening. In the discharge mode, the fluid resistance means that the fluid in the collecting basin, when same exits the outlet opening, will have to overcome a lower fluid resistance compared to when the same wants to exit through the inlet opening into the system. In the collecting mode, the fluid resistance means that the second gas from the system in the collecting basin has to overcome a smaller fluid resistance compared to when gas wants to enter the collecting basin from the atmosphere via the outlet opening. Thereby, it is ensured that foreign gas is collected in the collecting basin, which mostly originates from the system and not from the atmosphere. As has been discussed, the inlet opening and the outlet opening do not have to be completely closed or open. It is also not critical that the gas is completely removed, since the process of discharging the collecting basin can be repeated as often as desired. Hence, when a discharge process has not been completely successful, the same can simply be repeated one or several times. A limitation is here merely the ability of the means for generating the pressure to generate enough second gas, or the energy necessitated for generating the second gas, which has to be supplied.
The collecting basin is designed such that the same stores a water volume 11 in which a heat source 1 is disposed. In the embodiment of
At some stage, the safety valve will close and the inlet valve will open for preparing the collecting basin again for collecting foreign gases. Hence, it can happen that when the outlet opening opens, a pressure remains in the collecting basin, which is higher than the pressure within the evaporator. However, this is not critical, since this pressure is compensated immediately after opening the inlet opening. However, the gas going from the collecting basin into the evaporator volume is no foreign gas or a gas having only a very low proportion of foreign gas. Above this, the energy that this vapor has is also transferred into the evaporation process of the whole system, which is particularly advantageous when ecological heating systems, such as heat pumps, are considered, where any “waste of energy” has to be avoided.
Therewith, the water volume 12 in the collecting basin can be refilled after every discharge.
The foreign gases that are to be expected, such as air, are collected in the collecting basin 10 within the system 2. This collecting takes, for example, place gravitationally when the foreign gases are heavier than water vapor, which is the case for many foreign gases of interest, such as air, O2, CO2 or N2. Foreign gases that are lighter than water vapor can be easily trapped when the collecting basin in
In the case of “gravitationally” collecting the foreign gas, which is advantageous, a water volume 3 exists at the floor of the collecting basin 10. This is heated by means of the heat source, for example, an “emersion heater” until it evaporates. Thereby, the pressure in the basin rises further and further. This means the foreign gases are propelled out, through an especially provided outlet valve 4. At the same time, it is avoided that the foreign gases cannot penetrate into the closed system 2 of the heat pump evaporator. This is ensured by the outlet opening 5.
In the implementation, the heat source 1 can be automatically turned on and off, depending on the circumstances. For example 2 to 3 liters of water can be heated to the requested evaporation temperature in approximately 30 seconds by means of an energy source having 01 kW power.
The heat source 1 can be periodically activated by control 9 (shown in
In the following, a cycle of collecting mode and discharge mode will be illustrated in detail based on
Although it has been described above that the inventive apparatus for removing a gas, which is also referred to as gas trap, is arranged in the evaporator, the gas trap can additionally or alternatively also be arranged within the liquefier. Foreign gases such as nitrogen, oxygen, carbon and carbon dioxide or generally air from the environment are in particular a problem in the liquefier, since the compressor sucks off these gases anyway when they enter the evaporator. Although, generally, for producing the optimum evaporation and condensation process of water, obtaining a coarse vacuum is important, foreign gases have a more damaging effect in the liquefier than in the evaporator.
An arrangement of an inventive apparatus, which is also referred to as gas trap 50, in the liquefier 51 of a heat pump is shown in
Foreign gases sucked in by the compressor motor 53 by the evaporator are directed to the condenser water 56, due to the gas flow through the laminarizer 55, which runs off from the middle towards the side over the turbulence generator 58, which can be implemented, for example, in the form of wire mesh. It has shown that foreign gases are carried off laterally by the condenser water between the laminarizer 55 and the condenser water surface.
In order for the foreign gases to concentrate close to the gas trap 50, a sealing lip 59 is provided, which separates the lower gas region 60 from the upper gas region 61. In that way, the sealing lip 59 does not necessarily have to provide complete sealing. However, it ensures that the foreign gas transported by the condenser water on the condenser 57 concentrates below the condenser outlet 57 in the region 60. Since the foreign gases are heavier than water vapor, they fall into the gas trap 50 due to gravity. However, a diffusion process acts against gravity, in that the foreign gases in the region 60 and the gas trap will also want to have the same concentration. Hence, this diffusion process counteracts the gravity effect of the gas trap. However, this is relatively unproblematic since the concentration of the foreign gases does no longer take place in the region where condensation takes place but below the outlet 57. The sealing lip 59 prevents that the concentration in the region 60 and in the region 61 settle on the same value. Therewith, the concentration of the foreign gas in the region 60 will be higher than in the region 61, and a good trapping effect for foreign gases in the gas trap 50 will result.
It should be noted that the inventive effect of concentrating foreign gas in the region 60 compared to the region 61, where the actual condensation takes place, takes place even without laminization means 55 or without turbulence generator 58, merely due to the sealing lip 59, which affects separation of the lower region 60 from the upper region 61, or, respectively, represents a means which is implemented to effect a higher foreign gas concentration in the region around the gas trap compared to the region where liquefying or the largest part of the liquefying takes place.
However, the effect of the sealing lip 59 separating the region above the liquefier outlet or the liquefier funnel 57, respectively, from the region below this element 57 is increased further in that the laminization means 55 exists, since thereby the foreign gases can no longer disappear as soon as they hit the water flow 56 on the liquefier outlet 57, but are actually forced to run in the direction of the sealing lip and below the sealing lip for concentrating in the region of the gas trap 50. This behavior is increased further by the turbulence generator 58, since thereby a more turbulent flow exists, which also has a higher efficiency for trapping foreign gas and helping to carry it, since the same is within the upper region 61.
a shows a basic illustration of the functionality that has been illustrated based on the heat pump or the heat pump liquefier 51 of
Depending on the implementation, it is advantageous to implement the gas trap similar to
However, not the length of the neck 70 is of significance, but merely that at least the bottom part of the collecting basin 10 is arranged in a cold region, such as the evaporator 2 of the heat pump. This means that warm water vapor from the region 60 of the liquefier comes into contact with a cold surface of the collecting basin 1, which causes condensation of the water vapor. This results in a constant water vapor flow into the funnel 72 along the neck 70 into the collecting basin, since the water vapor condenses in the region 60 of the cold wall of the collecting basin arranged within the evaporator 2. The resulting flow into the gas trap has, on the one hand, the effect of carrying foreign gases also into the collecting basin, and, at the same time, of collecting water in the collecting basin, which can then be heated by the pressure generation means 1 in the form of a heating spiral for effecting vapor discharge. A laminarization means 73, such as in the form of a honeycomb structure, is also arranged at the funnel opening for improving the efficiency of the gas trap.
Particularly advantageous is the embodiment of arranging a wall of the collecting basin 10 in the evaporator, or generally, at a cold part of the system, when the heat pump is implemented such that the liquefier is arranged above the evaporator. In this implementation, the neck 70 reaches through the liquefier towards the bottom into the evaporator for providing a cold condensation wall, which, on the one hand, causes a constant gas flow into the gas trap and, on the other hand, also ensures that water exists in the gas trap, which can be heated for increasing the pressure in the collecting basin, such that foreign gas discharge can take place at certain events.
Although it has been described above that the gravitation effect supports the entry of the water vapor concentrated with foreign gases in the “capture range” of the gas trap, such as in the region 60 of
The cold region of the gas trap, which is obtained by arranging at least part of the gas trap, and in particular at least part of the collecting basin 10 of the gas trap in the evaporator of the heat pump, generally, can also be obtained by actively cooling a region of the gas trap or also by arranging the region of the gas trap which is to be the “cold” region, for example outside the heat pump. When the heat pump is located, for example, in a cellar, which has an inside temperature of approximately 10 degrees or 15 degrees, and when the temperature level in the liquefier is perhaps at 50 degrees, this temperature difference will already be sufficient for a reasonable gas flow, and the cold region of the gas trap does not necessarily have to be arranged directly in the evaporator of the heat pump, where even lower temperatures than in the cellar prevail. Generally, it is sufficient that the gas trap has a region having the effect that gas flow into the gas trap takes place, so that foreign gases are transported into the gas trap together with water vapor.
Then, condensation of the water vapor takes place at the cold region of the gas trap while the foreign gases do not condense and hence remain. This causes a concentration increase of foreign gases in the collecting basin of the gas trap, which will be reduced in the next discharge cycle.
The more the concentration of foreign gases increases in the collecting basin 10 of the gas trap, the harder it will be for the gas flow to introduce foreign gases from the inlet opening into the collecting basin of the gas trap, since, due to the concentration increase within the collecting basin, a diffusion flow exists for the foreign gases, which opposes the flow of the water vapor with foreign gases into the collecting basin 10.
For counteracting a standstill of introducing foreign gases into the collecting basin 10 due to this opposing flow as a result of the increased concentration of foreign gases in the collecting basin, a discharge mode is activated. Therefore, the liquid water generated in the collecting basin due to condensation of water vapor is vaporized. Thereby the pressure within the collecting basis 10 increases so much that the content of the collecting basin, consisting of vaporized water vapor and in particular the foreign gases, is discharged towards the atmosphere via the outlet opening, as illustrated by the arrow in
The discharge mode is shorter than the collecting mode, and the collecting mode, where a flow into the collecting basin 10 takes place and water vapor condenses, is three times as long as the discharge mode where water in the collecting basin is vaporized for increasing the pressure within the collecting basis so much that a discharge to the atmosphere takes place via the outlet opening. In particular embodiments, the collecting mode takes more than ten times as long as the discharge mode. For example, a collecting mode takes, for example, one minute or more and the discharge mode lasts then merely six seconds, or even less.
Although it has been noted above that the sealing lip 59, generally acting as means for separating the regions, increases the efficiency of the gas trap, it should be noted that for a basic functionality of the gas trap, the sealing lip 59 is not necessitated. Hence, due to the cold region of the gas trap, independent of whether concentration of foreign gases has already taken place in the lower region 60, flow into the gas trap will take place, where then condensation of the water vapor takes place in the cold air of the gas trap, whereupon the foreign gases remain. Thereby, already due to this effect, a concentration increase of the foreign gases within the collecting basin 10 is obtained, wherein these foreign gases are then discharged in the next discharge mode, which means they are removed from the whole system.
Depending on the circumstances, the inventive method can be implemented in hardware or in software. The implementation can be performed on a digital memory medium, in particular a disc or a CD having electronically readable control signals, that can cooperate with a programmable computer system such that the method is performed. Hence, generally, the invention also consists of a computer program product having a program code stored on a machine-readable carrier for performing the inventive method when the computer program product runs on a computer. In other words, the invention can be realized as a computer program having a program code for performing the method when the computer program runs on a computer.
While this invention has been described in terms of several advantageous embodiments, there are alterations, permutations, and equivalents which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and compositions of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102008005060.1 | Jan 2008 | DE | national |
| 102008031300.9 | Jul 2008 | DE | national |
This application is a U.S. National Phase entry of PCT/EP2009/000220 filed Jan. 15, 2009, and claims priority to German Patent Application No. 102008005060.1 filed Jan. 18, 2008 and German Patent Application No. 102008031300.9 filed Jul. 2, 2008, each of which is incorporated herein by references hereto.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2009/000220 | 1/15/2009 | WO | 00 | 1/19/2011 |
