Flash compression waste heat recovery system suitable for industrial waste liquid

Abstract

The utility model discloses a flash evaporation compression waste heat recovery system suitable for industrial waste liquid, belongs to the technical field of waste heat recovery of industrial waste liquid, and particularly relates to waste heat recovery from a waste water heat source with a high-pollution medium. The problem that in the prior art, in the field of industrial waste liquid waste heat, especially in the field of waste heat recovery of water for heat compensation of heating return water or process water, a reasonable waste heat recovery and waste water recycling mode is lacked so that consumption of energy, water resources and operation cost can be reduced is solved. The system comprises a flash tank; a flash evaporation steam outlet of the flash evaporation tank is communicated with a gas inlet of the compressor through a flash evaporation steam pipe; and a gas outlet of the compressor is communicated with a steam inlet of the spray tower. The flash evaporation compression waste heat recovery system suitable for the industrial waste liquid is suitable for recovering waste heat of the industrial waste liquid.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat recovery from industrial waste liquid, in particular to recovering waste heat from a waste water heat source with a highly polluted medium. Background Art

[0002] At present, the world is facing problems such as low energy utilization rate, poor economic benefits of energy utilization, and great pressure on the ecological environment caused by energy waste.

[0003] There are abundant industrial waste heat resources in the production processes of various industries, but at least 50% of industrial energy consumption is directly discarded in various forms of waste heat each year. The overall utilization rate of industrial waste heat has a large room for improvement, and the potential for industrial energy conservation is huge.

[0004] Among all industrial waste heat resources, the most common is waste water waste heat. Waste water waste heat is a low-grade waste heat with a temperature below 100°C; waste water waste heat includes condensed water, sewage and waste water from various production and life processes generated by cooling and concentration in the chemical, metallurgical and food industries; waste water waste heat accounts for about 10% to 16% of industrial waste heat resources.

[0005] If the waste heat of wastewater cannot be reasonably utilized in a reasonable way, it will inevitably lead to a huge waste of energy. At the same time, the inability to recycle wastewater will also lead to increasingly scarce water resources. In addition, for heating return water or process water, the water used for heat replenishment is softened or deoxygenated water, and the price of this water is as high as 5 yuan / t to 10 yuan / t. The waste of wastewater will also increase the operating cost of heating or process water.

[0006] In summary, in the field of industrial waste liquid waste heat, especially in the field of waste heat recovery of heating return water or process water, there is a lack of reasonable waste heat recovery and wastewater recycling methods to reduce the consumption of energy, water resources and operating costs. Utility Model Content

[0007] The utility model proposes a flash compression waste heat recovery system suitable for industrial waste liquid, which solves the problem of the existing technology in the field of industrial waste liquid waste heat, especially the field of waste heat recovery of heating return water or process water heating water, lacking a reasonable waste heat recovery and wastewater recycling method to reduce the consumption of energy, water resources and operating costs.

[0008] The utility model discloses a flash compression waste heat recovery system suitable for industrial waste liquid, and its technical scheme is as follows:

[0009] The system comprises: a flash tank, a water withdrawal pump, a compressor, a spray tower, a liquid inlet pipe, a liquid withdrawal pipe, a flash steam pipe and a steam pipe;

[0010] The liquid inlet pipe is used to input industrial waste liquid into the flash tank;

[0011] The flash steam outlet of the flash tank is connected to the gas inlet of the compressor through a flash steam pipe; the gas outlet of the compressor is connected to the steam inlet of the spray tower;

[0012] The waste liquid outlet of the flash tank is connected to the inlet of the water withdrawal pump through a liquid withdrawal pipe; the outlet of the water withdrawal pump is used to discharge the waste liquid.

[0013] Further, a preferred embodiment is provided, wherein the system further comprises: a water supply pipe and a hot water pump;

[0014] The bottom water outlet of the spray tower is connected with the inlet of the hot water pump through a water supply pipe.

[0015] Further, a preferred embodiment is provided, wherein the system comprises: a return pipe, a circulation pump, a return pipe and a sprinkler head;

[0016] The bottom water outlet of the spray tower is connected to the water inlet of the water spray head through the return pipe, the circulation pump and the return pipe, and the water outlet of the water spray head is used to spray the spray liquid into the spray tower.

[0017] Further, a preferred embodiment is provided, wherein the system further comprises: a vacuum pump and a vacuum tube;

[0018] The vacuum suction port of the spray tower is connected to the inlet of the vacuum pump through the vacuum pipe.

[0019] The utility model has the following beneficial effects:

[0020] 1. The flash compression waste heat recovery system suitable for industrial waste liquid described in the utility model takes the industrial waste liquid as the waste heat source, maximizes the use of the heat energy in the industrial waste liquid, reduces energy consumption, and reduces adverse effects on the environment.

[0021] 2. The flash compression waste heat recovery system suitable for industrial waste liquid described in the utility model adopts a compressor gas compression method to compress the flash vapor to a superheated state, thereby improving the thermal quality of the flash vapor and facilitating subsequent heat exchange.

[0022] 3. The flash compression waste heat recovery system suitable for industrial waste liquid described in the utility model adopts flash phase change heat transfer to recover waste heat from industrial waste liquid, and at the same time condenses the flash vapor into condensed water, and uses the condensed water to replenish heating return water or process water, thereby maximizing the use of waste heat energy and water resources in industrial waste water and saving the operating cost of heating return water or process water.

[0023] The utility model discloses a flash compression waste heat recovery system suitable for industrial waste liquid, which is suitable for recovering the waste heat of industrial waste liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the implementation modes of the present invention, the drawings required for use in the implementation modes will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 In one embodiment of the utility model, a structural diagram of a flash compression waste heat recovery system suitable for industrial waste liquid;

[0026] Reference numerals:

[0027] 1. Flash tank; 2. Water return pump; 3. Compressor; 4. Spray head; 5. Spray tower; 6. Vacuum pump; 7. Circulation pump; 8. Hot water pump; 1-1. Liquid inlet pipe; 1-2. Cooling pipe; 1-3. Flash steam pipe; 3-1. Steam pipe; 4-1. Return pipe; 5-1. Water supply pipe; 6-1. Vacuum pipe; 7-1. Reflux pipe. DETAILED DESCRIPTION

[0028] In order to make the technical solutions and advantages of the utility model more clearly described, the specific implementation methods of the utility model will be further described in detail and completely in conjunction with the accompanying drawings. The various implementation methods described below are only part of the preferred solutions of the utility model, not all implementation methods; the various implementation methods described below are intended to explain the utility model and cannot be understood as limitations on the utility model; the reasonable combination of technical features defined in each implementation method of the utility model, and all other implementation methods obtained by ordinary technicians in the field without creative work based on the implementation methods of the utility model, are within the scope of protection of the utility model.

[0029] Implementation Method 1: Combination Figure 1 This embodiment describes a flash compression waste heat recovery system suitable for industrial waste liquid, and the specific implementation contents are as follows:

[0030] The system comprises: a flash tank 1, a water withdrawal pump 2, a compressor 3, a spray tower 5, a liquid inlet pipe 1-1, a liquid withdrawal pipe 1-2, a flash steam pipe 1-3 and a steam pipe 3-1;

[0031] The liquid inlet pipe 1-1 is used to input industrial waste liquid into the flash tank 1;

[0032] The flash steam outlet of the flash tank 1 is connected to the gas inlet of the compressor 3 through the flash steam pipe 1-3; the gas outlet of the compressor 3 is connected to the steam inlet of the spray tower 5;

[0033] The waste liquid outlet of the flash tank 1 is connected to the inlet of the water withdrawal pump 2 through the liquid withdrawal pipe 1-2; the outlet of the water withdrawal pump 2 is used to discharge the waste liquid.

[0034] In this embodiment, the flash tank 1 is used to cause the industrial waste liquid to undergo a flash phase change to obtain flash vapor and residual waste liquid (referred to as waste liquid). The flash tank 1 has a flash vapor outlet and a waste liquid outlet, the flash vapor flows out of the flash tank 1 through the flash vapor outlet, and the waste liquid flows out of the flash tank 1 through the waste liquid outlet.

[0035] In this embodiment, the compressor 3 is used to keep the flash tank 1 in a negative pressure state and to compress the flash vapor flowing out of the flash tank 1; the spray tower 5 is used to recover the waste heat of the compressed flash vapor.

[0036] In this embodiment, industrial waste liquid is used as the waste heat source to maximize the use of heat energy in the industrial waste liquid, thereby reducing energy consumption and reducing adverse impacts on the environment.

[0037] In this embodiment, a compressor gas compression method is adopted to compress the flash vapor to a superheated state, thereby improving the thermal quality of the flash vapor and facilitating subsequent heat exchange.

[0038] In this embodiment, the flash tank is used to achieve rapid flash evaporation and pressure reduction of industrial waste liquid, so that the industrial waste liquid is separated into gas and liquid at low temperature and low pressure, and then used to produce flash vapor.

[0039] In this embodiment, the compressor is used to compress the flash steam to improve the steam quality.

[0040] In this embodiment, the flash tank 1 is kept in a negative pressure state under the action of the compressor 3 .

[0041] In this embodiment, industrial waste liquid flows into the flash tank 1 through the liquid inlet pipe 1-1 for phase change flash evaporation, and the flash vapor from the flash evaporation enters the compressor 3 through the flash vapor pipe 1-3 for compression, and the industrial waste liquid that is not completely flashed is discharged from the flash tank 1 through the liquid withdrawal pipe 1-2 via the water withdrawal pump 2.

[0042] In this embodiment, the flash vapor generated from the flash tank 1 is compressed by the compressor 3 to increase the temperature and pressure, and then enters the spray tower 5 through the steam pipe 3 - 1 .

[0043] Implementation Method 2: Combination Figure 1This embodiment is described. This embodiment is a further limitation of the flash compression waste heat recovery system for industrial waste liquid described in the first embodiment. The specific implementation contents are as follows:

[0044] The system further comprises: a water supply pipe 5-1 and a hot water pump 8;

[0045] The bottom water outlet of the spray tower 5 is connected to the inlet of the hot water pump 8 through the water supply pipe 5 - 1 .

[0046] In this embodiment, the water supply pipe 5 - 1 is arranged at the lower half of the spray tower 5 .

[0047] In this embodiment, the water supply pipe 5 - 1 is used to supply hot water to the outside.

[0048] Implementation Method 3: Combination Figure 1 This embodiment is described as a further limitation of the flash compression waste heat recovery system for industrial waste liquid described in Embodiment 2. The specific implementation contents are as follows:

[0049] The system comprises: a return pipe 7-1, a circulation pump 7, a return pipe 4-1 and a sprinkler head 4;

[0050] The bottom water outlet of the spray tower 5 is connected to the water inlet of the spray head 4 through the return pipe 7 - 1 , the circulation pump 7 and the return pipe 4 - 1 . The water outlet of the spray head 4 is used to spray the spray liquid into the spray tower 5 .

[0051] In this embodiment, the water outlet of the water spray head 4 is located at the inner top of the spray tower 5 .

[0052] In this embodiment, a portion of the liquid flowing out of the bottom water outlet of the spray tower 5 is supplied to the outside through the water supply pipe 5-1 and the hot water pump 8, and the other portion is sprayed back to the spray tower 5 through the return pipe 7-1, the circulation pump 7, the return pipe 4-1 and the spray head 4.

[0053] In this embodiment, the spray liquid sprayed back to the spray tower 5 through the water outlet of the spray head 4 is used to recover the waste heat of the compressed flash steam and to condense the flash steam into condensed water.

[0054] In this embodiment, the spraying liquid is heating return water or process water.

[0055] In this embodiment, a flash evaporation phase change heat transfer method is adopted to recover waste heat from industrial waste liquid, and at the same time, the flash vapor is condensed into condensed water, and the condensed water is used to replenish heating return water or process water, thereby maximizing the utilization of waste heat energy and water resources in industrial waste water and saving the operating cost of heating return water or process water.

[0056] In this embodiment, the spray tower is used to realize flash steam condensation and to recover and store condensed water.

[0057] In this embodiment, the water spray head is used to spray the liquid all over the spray tower to increase the heat exchange area of ​​the liquid, thereby strengthening the heat and mass transfer between the flash vapor and the spray liquid and enhancing the heat exchange effect; at the same time, the flash vapor is condensed to recover the condensed water for water replenishment.

[0058] In this embodiment, heating return water or process water is used as spray liquid; the spray liquid enters the spray tower 5 in the form of spray through the return pipe 4-1 and the spray head 4; in this process, the water molecules in the spray liquid enter the spray tower in the form of small droplets, so that the liquid spreads throughout the spray tower, increasing the heat exchange area of ​​the liquid, strengthening the heat and mass transfer between the flash steam and the spray liquid, and enhancing the heat exchange effect.

[0059] In this embodiment, heat is exchanged between the flash steam and the spray liquid, and the flash steam is condensed into condensed water while recovering the waste heat. The condensed water can be used for water replenishment to reduce the waste of water resources. The heating return water or process water used as the spray liquid and the condensed water condensed from the flash steam are mixed and stored in the spray tower 5.

[0060] In this embodiment, a part of the liquid stored in the spray tower 5 is supplied to the heat users through the water supply pipe 5 - 1 via the hot water circulation pump 8 .

[0061] In this embodiment, another part of the liquid stored in the spray tower 5 enters the circulation again through the return pipe 4 - 1 and the spray head 4 through the return pipe 7 - 1 to achieve sufficient heat exchange with the flash steam.

[0062] Implementation Method 4: Combination Figure 1 This embodiment is described as a further limitation of the flash compression waste heat recovery system for industrial waste liquid described in Embodiment 3. The specific implementation contents are as follows:

[0063] The system further comprises: a vacuum pump 6 and a vacuum tube 6-1;

[0064] The vacuum exhaust port of the spray tower 5 is connected to the inlet of the vacuum pump 6 through the vacuum pipe 6 - 1 .

[0065] In this embodiment, the spray tower 5 also has a vacuum exhaust port.

[0066] In this embodiment, the vacuum pump 6 maintains a negative pressure state of the entire system by pumping air, thereby ensuring the flash evaporation effect of the system.

[0067] The technical solution provided by the present invention is further described in detail above through several specific implementation modes in order to highlight the advantages and benefits of the technical solution provided by the present invention. However, the several specific implementation modes described above are not intended to limit the present invention. Any reasonable changes and improvements to the present invention, reasonable combinations of implementation modes and equivalent substitutions based on the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A flash compression waste heat recovery system suitable for industrial waste liquid, characterized in that: The system comprises: a flash tank (1), a water withdrawal pump (2), a compressor (3), a spray tower (5), a liquid inlet pipe (1-1), a liquid withdrawal pipe (1-2), a flash steam pipe (1-3) and a steam pipe (3-1); The liquid inlet pipe (1-1) is used to input industrial waste liquid into the flash tank (1); The flash steam outlet of the flash tank (1) is connected to the gas inlet of the compressor (3) through the flash steam pipe (1-3); the gas outlet of the compressor (3) is connected to the steam inlet of the spray tower (5); The waste liquid outlet of the flash tank (1) is connected to the inlet of a water withdrawal pump (2) through a liquid withdrawal pipe (1-2); the outlet of the water withdrawal pump (2) is used to discharge the waste liquid.

2. A flash compression waste heat recovery system suitable for industrial waste liquid according to claim 1, characterized in that: The system also includes: a water supply pipe (5-1) and a hot water pump (8); The water outlet at the bottom of the spray tower (5) is connected to the inlet of the hot water pump (8) through a water supply pipe (5-1).

3. A flash compression waste heat recovery system suitable for industrial waste liquid according to claim 2, characterized in that: The system comprises: a return pipe (7-1), a circulation pump (7), a return pipe (4-1) and a water spray head (4); The bottom water outlet of the spray tower (5) is connected to the water inlet of the spray head (4) through the return pipe (7-1), the circulation pump (7) and the return pipe (4-1), and the water outlet of the spray head (4) is used to spray spray liquid into the spray tower (5).

4. A flash compression waste heat recovery system suitable for industrial waste liquid according to claim 3, characterized in that: The system also includes: a vacuum pump (6) and a vacuum tube (6-1); The vacuum suction port of the spray tower (5) is connected to the inlet of the vacuum pump (6) through the vacuum pipe (6-1).

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