Water treatment apparatus

Abstract

The invention relates to a water treatment device. The water treatment device has an inlet for water, a first outlet for treated water and a second outlet for waste water, an evaporator, a condenser and a compressor. The inlet is connected to the evaporator. The second outlet is likewise connected to the evaporator. An evaporator outlet of the evaporator is connected to a condenser inlet of the condenser. A condenser outlet of the condenser is connected to the first outlet. The compressor is arranged between the evaporator outlet and the condenser inlet. The compressor is provided for generating a negative pressure on the side of the evaporator outlet. The condenser comprises a heat exchanger, wherein the condenser inlet and the condenser outlet are connected to a first fluid space of the heat exchanger. A second fluid space of the heat exchanger has a heat exchanger inlet and a heat exchanger outlet. The heat exchanger outlet is connected to the evaporator. The evaporator is connected to the evaporator inlet. The evaporator and the second fluid space are configured in such a way that a hydrophobic liquid is heated in the second fluid space of the condenser as a result of the condensation of water vapor in the first fluid space of the condenser and the condensation heat occurring there and can subsequently transfer the heat in the evaporator to water arranged in the evaporator.

Description

Technical Field

[0001] This invention relates to a water treatment device and a method for operating the water treatment device. Background Technology

[0002] Water treatment equipment is known in which water can be treated by means of reverse osmosis (RO). Furthermore, water treatment equipment is known to operate by means of mechanical vapor compression distillation (MVCD) and is used, for example, in seawater desalination equipment. Additionally, water treatment equipment for a single extraction point is known, in which, importantly, the water supplied via the inlet pipe is cleaned, desalinated, and decalcified before use, especially in countries with contaminated water, for example, to decalcify the water.

[0003] In water treatment equipment operating via vapor compression distillation, an evaporator is provided, in which water is converted into water vapor. Materials that should be removed from the water can accumulate in the evaporator. To save energy, for example, one fluid space of a heat exchanger can be used as an evaporator, while another fluid space is used to condense the water vapor. Due to the accumulation of compounds, such as those containing calcium or magnesium, the fluid spaces need to be cleaned, which is technically laborious. Summary of the Invention

[0004] The objective of this invention is to provide an improved water treatment apparatus and an improved method for operating the water treatment apparatus.

[0005] The task is solved by means of the subject matter according to the invention. Advantageous extensions are given below.

[0006] This invention includes a water treatment apparatus. The water treatment apparatus has an inlet for water, a first outlet for treated water, and a second outlet for wastewater, an evaporator, a condenser, and a compressor. The inlet is connected to the evaporator. The second outlet is also connected to the evaporator. The evaporator outlet of the evaporator is connected to the condenser inlet of the condenser. The condenser outlet of the condenser is connected to the first outlet. The compressor is arranged between the evaporator outlet and the condenser inlet. The compressor is configured to generate a negative pressure on the side of the evaporator outlet. The condenser includes a heat exchanger, wherein the condenser inlet and condenser outlet are connected to a first fluid space of the heat exchanger. The second fluid space of the heat exchanger has a heat exchanger inlet and a heat exchanger outlet. The heat exchanger outlet is connected to the evaporator. The evaporator is connected to the evaporator inlet. The evaporator and the second fluid space are configured such that a hydrophobic liquid in the second fluid space of the condenser is heated in the condenser due to the condensation of water vapor in the first fluid space of the condenser and the heat of condensation thereon, and can subsequently transfer heat to the water arranged in the evaporator.

[0007] Here, a hydrophobic liquid is used as the medium for heat transfer. The transfer of heat from the hydrophobic liquid to the water arranged in the evaporator takes place directly within the evaporator, where the hydrophobic liquid and water are essentially immiscible, with a solid-phase interface formed between them. Heat transfer occurs directly at this interface.

[0008] Here, the hydrophobic liquid can be, in particular, an organic liquid. Furthermore, the hydrophobic liquid can be, in particular, a liquid with an octanol-water partition coefficient greater than 1, especially greater than 1.5. The stronger the hydrophobicity of the liquid, the larger the octanol-water partition coefficient. Furthermore, it can be proposed that the hydrophobic liquid is food-grade. Then, the water treatment equipment can also be used, for example, for drinking water treatment. Such food-grade hydrophobic liquid can, for example, be based on hydrogenated heavy paraffin distilled petroleum, wherein the mass fraction of this substance is greater than 90%. A commercially available hydrophobic liquid suitable for heat transfer is Duratherm FG. It can be proposed that the hydrophobic liquid is thermally stable, especially for temperatures below 130 degrees Celsius, preferably below 150 degrees Celsius, and particularly preferably below 200 degrees Celsius.

[0009] The hydrophobic liquid is heated in the second fluid chamber instead of evaporated, and the absorbed heat can be dissipated again in the evaporator. Thus, the second fluid chamber remains essentially free of dissolved salts and other materials, eliminating or at least significantly reducing the frequency of laborious cleaning of the second fluid space. In particular, this reduces or prevents calcification of the second fluid space.

[0010] Furthermore, the present invention also includes a method for operating such a water treatment apparatus. A hydrophobic liquid is heated in the second fluid space of a condenser due to the condensation of water vapor in the first fluid space of the condenser and the heat of condensation occurring therein. Subsequently, the hydrophobic liquid transfers heat to water arranged in an evaporator.

[0011] In one embodiment of the water treatment equipment, the evaporator has a nozzle for a hydrophobic liquid and a separator for the same liquid. The nozzle is connected to the outlet of a heat exchanger. The separator is connected to the inlet of the heat exchanger. The nozzle generates droplets of the hydrophobic liquid with a predetermined diameter or a predetermined diameter distribution. The surface area to volume ratio of the droplets can be selected to optimize the heat exchange between the hydrophobic liquid and the water. The separator separates the hydrophobic liquid from the water, ensuring that as little water as possible reaches the heat exchanger inlet.

[0012] In one embodiment of a water treatment device, a separator can separate the hydrophobic liquid from the water due to the difference in density between the hydrophobic liquid and water. The density of hydrophobic organic liquids is generally less than that of water, causing the hydrophobic liquid to float on top of the water and allowing for separation using a separator. A separator can also be used when the density of the hydrophobic liquid is greater than that of water.

[0013] In one embodiment of the water treatment equipment, a plurality of nozzles are provided, the nozzles being configured to generate droplets of the hydrophobic liquid having a diameter between 0.5 mm and 2 mm. These diameters are suitable for good heat transfer.

[0014] In one embodiment of the water treatment equipment, a cyclone separator is arranged between the separator and the inlet of the heat exchanger. This allows for further separation of the hydrophobic liquid from the water.

[0015] In one embodiment of the water treatment equipment, the water treatment equipment further includes a heating device. This heating device may be arranged, for example, in an evaporator, and is capable of introducing additional heating power.

[0016] In one embodiment of the water treatment equipment, a heating device is arranged between the heat exchanger outlet and the evaporator. The hydrophobic liquid can then be heated using this heating device, thereby reducing or preventing calcification of the heating device.

[0017] In one embodiment of the water treatment equipment, the equipment further includes a control unit, a controllable valve between the inlet (101) and the evaporator, an inflow measuring device, and an outflow measuring device. The inflow measuring device is configured to determine the amount of water flowing in via the inlet and output a corresponding signal to the control unit. The outflow measuring device is configured to determine the amount of water flowing out via the condenser outlet and output a corresponding signal to the control unit. The control unit is configured to control the controllable valve based on the signals and the operating mode. Here, the operating method may include, for example, a batch method, in which the evaporator is emptied by water evaporation and then new water is supplied. In a continuous method, the same amount of water can be supplied via the inlet for the water discharged via the condenser outlet, making continuous operation possible.

[0018] In one embodiment of the water treatment equipment, the evaporator comprises a vertical cylindrical container. A hydrophobic liquid and water can form opposing flows within the evaporator by gravity. If the density of the hydrophobic liquid is less than that of water, the hydrophobic liquid can rise in the water. If the density of the hydrophobic liquid is greater than that of water, the hydrophobic liquid can sink in the water.

[0019] In one embodiment of the water treatment equipment, a cooling unit is arranged between the evaporator and the heat exchanger inlet, wherein the cooling unit is in thermal contact with the compressor. This can improve efficiency. Attached Figure Description

[0020] Embodiments of the present invention will now be described with reference to the accompanying drawings. The schematic drawings show: Figure 1 Showing water treatment equipment; Figure 2 Additional water treatment equipment is shown; Figure 3 Additional water treatment equipment is shown. Detailed Implementation

[0021] Figure 1A water treatment apparatus 100 is shown, comprising an inlet 101 for water, a first outlet 102 for treated water, and a second outlet 103 for wastewater, an evaporator 110, a condenser 120, and a compressor 130. The inlet 101 is connected to the evaporator 110. The second outlet 103 is also connected to the evaporator 110 and is used to discharge water rich in impurities. The evaporator outlet 111 of the evaporator 110 is connected to the condenser inlet 121 of the condenser 120. The condenser outlet 122 of the condenser 120 is connected to the first outlet 102. The compressor 130 is arranged between the evaporator outlet 111 and the condenser inlet 121. The compressor 130 is configured to generate a negative pressure on the side of the evaporator outlet 111. The condenser 120 includes a heat exchanger 123, wherein the condenser inlet 121 and the condenser outlet 122 are connected to a first fluid space 124 of the heat exchanger 123. The second fluid space 125 of the heat exchanger has a heat exchanger inlet 126 and a heat exchanger outlet 127. The heat exchanger outlet 127 is connected to the evaporator 110. Furthermore, the evaporator 110 is connected to the heat exchanger inlet 126. The evaporator 110 and the second fluid space 125 are configured such that the hydrophobic liquid 105 is heated in the second fluid space 125 of the condenser 120 due to the condensation of water vapor 106 in the first fluid space 124 of the condenser 120 and the heat of condensation thereon, and can subsequently transfer the heat to the water 107 arranged in the evaporator 100 in the evaporator 110.

[0022] That is, the method for operating such a water treatment device 100 includes: heating a hydrophobic liquid 105 in a second fluid space 125 of a condenser 120, and then guiding the hydrophobic liquid to an evaporator 110 via a heat exchanger outlet 127. In the evaporator 110, droplets of the hydrophobic liquid 105 form in water 107, wherein the droplets of the hydrophobic liquid 105 dissipate heat to the water 107. Bubbles of water vapor 106 are formed here, which rise through the water 107 and the hydrophobic liquid 105 and thus reach the evaporator outlet 111. From there, the water vapor 106 is guided via a compressor 130 to a condenser inlet 121, and then condenses in a first fluid space 124 of the condenser 120. The heat of condensation generated here is again dissipated to the hydrophobic liquid 105 in the second fluid space 125.

[0023] Here, the hydrophobic liquid 105 is used as the medium for heat transfer. The transfer of heat from the hydrophobic liquid 105 to the water 107 arranged in the evaporator 110 takes place directly within the evaporator 110, wherein the hydrophobic liquid 105 and water 107 are substantially immiscible, but a solid-phase interface is formed between them, such as... Figure 1 As shown, heat transfer occurs directly at this phase boundary.

[0024] Here, the hydrophobic liquid 105 can be, in particular, an organic liquid. Furthermore, the hydrophobic liquid 105 can be, in particular, a liquid with an octanol-water partition coefficient greater than 1, especially greater than 1.5. The stronger the hydrophobicity of the liquid 105, the larger the octanol-water partition coefficient. Furthermore, it can be proposed that the hydrophobic liquid 105 is food-grade. Then, the water treatment device 100 can also be used, for example, for drinking water treatment. Such a food-grade hydrophobic liquid 105 can, for example, be based on hydrogenated heavy paraffin distilled petroleum, wherein the mass fraction of this substance is greater than 90%. Such a commercially available hydrophobic liquid 105, also suitable for heat transfer, is Duratherm FG. It can be proposed that the hydrophobic liquid 105 is thermally stable, especially for temperatures below 130 degrees Celsius, preferably below 150 degrees Celsius, and particularly preferably below 200 degrees Celsius.

[0025] The hydrophobic liquid 105 is not evaporated in the second fluid chamber 125, but rather heated, and the absorbed heat can be dissipated again in the evaporator 110. Thus, the second fluid chamber 125 remains substantially free of salts and other materials dissolved in water, making it possible to eliminate or at least significantly reduce the frequency of laborious cleaning of the second fluid chamber 125. In particular, this reduces or prevents calcification of the second fluid chamber 125.

[0026] Figure 1 In this embodiment, the hydrophobic liquid 105 has a lower density than water 107, causing the hydrophobic liquid 105 to rise in the evaporator 110. Similarly, water vapor 106 rises in the evaporator 110.

[0027] In addition, Figure 1 The optional features are shown, which can be set separately. The additional features can be set in any combination.

[0028] Optionally, the evaporator 110 includes a nozzle 112 for the hydrophobic liquid 105 and a separator 113 for the hydrophobic liquid 105. The nozzle 112 is connected to the heat exchanger outlet 127. The separator 113 is connected to the heat exchanger inlet 126. The nozzle 112 is arranged in the lower region of the evaporator 110 so that droplets of the hydrophobic liquid 105 travel as far as possible in the water 107. The separator 113 is arranged in the upper region of the evaporator 110 because the hydrophobic liquid 105 rises in the evaporator 110 and can be removed there. For this purpose, the separator 113 has an edge 114, wherein the inflow control for the water 110 can prevent water 106 from reaching the edge 114. That is, due to the density difference between the hydrophobic liquid 105 and the water 107, the separator 113 can optionally achieve the separation of the hydrophobic liquid 105 and the water 107.

[0029] The nozzle 112 may optionally be configured to generate droplets 108 of hydrophobic liquid having a diameter 109 between 0.5 mm and 2 mm.

[0030] Optionally, a cyclone separator 116 is arranged between separator 113 and heat exchanger inlet 126. The outlet 117 of the cyclone separator is connected to a second outlet 103. The riser 118 of the cyclone separator 116 is connected to the heat exchanger inlet 126. This allows for the separation of residual water in the hydrophobic liquid 105.

[0031] Optionally, the water treatment apparatus 100 includes a heating device 132. The heating device 132 is arranged between the heat exchanger outlet 127 and the evaporator 110. That is, the heating device 132 is used to additionally heat the hydrophobic liquid 105. In addition, an optional circulation pump 133 is shown, by means of which the hydrophobic liquid 105 can be moved from the evaporator 110 to the second fluid space 125 of the condenser 120 and back.

[0032] Furthermore, an optional control unit 140, an optional controllable valve 141 between inlet 101 and evaporator 110, an optional inflow measuring device 142, and an optional outflow measuring device 143 are shown. The inflow measuring device 142 is configured to determine the amount of water flowing in via inlet 101 and output a corresponding signal to control unit 140. The outflow measuring device 143 is configured to determine the amount of water flowing out via condenser outlet 127 and output a corresponding signal to control unit 140. Control unit 140 is configured to control controllable valve 141 according to the signals and operating mode. Here, the operating method may include, for example, a batch method, in which the evaporator 110 is emptied by the evaporation of water 107 and then new water 107 is supplied. In a continuous method, the same amount of water discharged via condenser outlet 122 can be supplied via inlet 101, making continuous operation possible.

[0033] Optionally, the water treatment equipment 100 has a storage tank 144 between the condenser outlet 122 and the first outlet 102. Additionally, an optional drain valve 104 is shown, by which the discharge of water rich in impurities via the second outlet 103 can be performed.

[0034] Optionally, the evaporator 110 includes a vertical cylindrical container 129. Hydrophobic liquid 105 and water 107 can form opposing flows within the evaporator 110 by gravity. This can... Figure 1 In the evaporator 110, this is achieved by the following arrangement: the inlet 101 is arranged in the upper region of the evaporator 110, and the nozzle 112 is arranged in the lower region.

[0035] Here, the heat exchanger 123 can be configured, for example, as a plate heat exchanger or a tube bundle heat exchanger.

[0036] Figure 2 An additional water treatment device 100 is shown, which, unless otherwise described below, corresponds to... Figure 1 Water treatment equipment 100. In this embodiment, a plurality of nozzles 112 are provided in the evaporator 110. These nozzles 112 may be optionally configured to generate droplets 108 of hydrophobic liquid having a diameter 109 between 0.5 mm and 2 mm.

[0037] Alternatively, a cooling unit may be arranged between the evaporator 110 and the heat exchanger inlet 126, wherein the cooling unit is in thermal contact with the compressor 130. This can improve efficiency because the hydrophobic liquid 105 can be additionally heated by the waste heat from the compressor 130.

[0038] Also in Figure 2 As shown, the heating device 132 is arranged inside the evaporator 110.

[0039] Figure 3 An embodiment of a water treatment device 100 is shown, and unless otherwise described below, this water treatment device corresponds to... Figure 1 Water treatment device 100. In this embodiment, the density of hydrophobic liquid 105 is greater than that of water 107, causing droplets 108 of hydrophobic liquid 105 to sink in evaporator 110. Therefore, nozzles are arranged in the upper region of evaporator 110. Separator 113 is configured such that edge 114 is located above the liquid level of hydrophobic liquid 105 and water can flow out through this edge.

[0040] In the case of cyclone separator 116, outlet 11 is connected to heat exchanger inlet 126, and riser is connected to second outlet 103.

[0041] Figure 1 All the optional features of the water treatment equipment 100 are also present. Furthermore, it is also possible to set... Figure 2 Optional features of water treatment equipment.

[0042] Although the invention has been described in detail by way of preferred embodiments, the invention is not limited to the disclosed examples, and those skilled in the art can derive other variations therefrom without departing from the scope of protection of the invention.

Claims

1. A water treatment apparatus (100) comprising an inlet (101) for water, a first outlet (102) for treated water and a second outlet (103) for wastewater, an evaporator (110), a condenser (120) and a compressor (130), wherein, The inlet (101) is connected to the evaporator (110), and the second outlet (103) is connected to the evaporator (110). The evaporator outlet (111) of the evaporator (110) is connected to the condenser inlet (121) of the condenser (120). The condenser outlet (122) of the condenser (120) is connected to the first outlet (102). The compressor (130) is arranged between the evaporator outlet (111) and the condenser inlet (121). The compressor (130) is configured to generate a negative pressure on the evaporator outlet (111) side. The condenser (120) includes a heat exchanger (123). The condenser inlet (121) and the condenser outlet (122) are connected to the first flow path of the heat exchanger (123). The heat exchanger is connected to a body space (124), wherein the second fluid space (125) of the heat exchanger has a heat exchanger inlet (126) and a heat exchanger outlet (127), wherein the heat exchanger outlet (127) is connected to the evaporator (110), wherein the evaporator (110) is connected to the heat exchanger inlet (126), wherein the evaporator (110) and the second fluid space (125) are configured such that the hydrophobic liquid (105) in the second fluid space (125) of the condenser (120) is heated by the condensation of water vapor (106) in the first fluid space (124) of the condenser (120) and the heat of condensation thereon, and is subsequently able to transfer heat to the water (107) arranged in the evaporator (110).

2. The water treatment equipment (100) according to claim 1, wherein, The evaporator (110) includes a nozzle (112) for the hydrophobic liquid (105) and a separator (113) for the hydrophobic liquid (105), wherein the nozzle (112) is connected to the heat exchanger outlet (127) and the separator (113) is connected to the heat exchanger inlet (126).

3. The water treatment equipment (100) according to claim 2, wherein, Because the hydrophobic liquid (105) and the water (107) have different densities, the separator (113) can separate the hydrophobic liquid (105) from the water (107).

4. The water treatment equipment (100) according to claim 2 or 3, wherein, The system is provided with a plurality of nozzles (112) configured to produce droplets (108) of the hydrophobic liquid having a diameter (109) between 0.5 mm and 2 mm.

5. The water treatment equipment (100) according to any one of claims 1 to 3, wherein, A cyclone separator (116) is arranged between the evaporator (110) and the heat exchanger inlet (126).

6. The water treatment apparatus (100) according to any one of claims 1 to 3, wherein the water treatment apparatus further comprises a heating device (132).

7. The water treatment equipment (100) according to claim 6, wherein, The heating device (132) is arranged between the heat exchanger outlet (127) and the evaporator (110).

8. The water treatment apparatus (100) according to any one of claims 1 to 3, further comprising a control unit (140), a controllable valve (141) between the inlet (101) and the evaporator (110), an inflow measuring device (142), and an outflow measuring device (143), wherein, The inflow measuring device (142) is configured to determine the amount of water flowing in through the inlet (101) and output a corresponding signal to the control unit (140), wherein the outflow measuring device (143) is configured to determine the amount of water flowing out through the condenser outlet (122) and output a corresponding signal to the control unit (140), wherein the control unit (140) is configured to control the controllable valve (141) according to the signal and the operating mode.

9. The water treatment equipment (100) according to any one of claims 1 to 3, wherein, The evaporator (110) includes a vertical cylindrical container (129) in which hydrophobic liquid (105) and water (107) can form corresponding opposing flows in the evaporator (110) by means of gravity.

10. A method for operating a water treatment apparatus (100) according to any one of the preceding claims, wherein, The hydrophobic liquid (105) is heated in the second fluid space (125) of the condenser (120) due to the condensation of water vapor (106) in the first fluid space (124) of the condenser (120) and the heat of condensation thereon, and then transfers the heat to the water (107) arranged in the evaporator (110).

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