Spraying cooling system

Abstract

A spraying cooling system, comprising a spraying cooling tower (1), a concentration device (3), and a plurality of spraying assemblies (2), wherein a plurality of spraying areas which are sequentially spaced apart from each other in a fume flow direction are provided in the spraying cooling tower (1), and the plurality of spraying assemblies (2) correspond to the plurality of spraying areas on a one-to-one basis so as to spray a spraying solution into the spraying areas; and the concentration device (3) comprises a preheating assembly (31) and a separation assembly (32), wherein the preheating assembly (31) is connected to at least one spraying assembly (2) of the plurality of spraying assemblies (2) and is configured to preheat part of the spraying solution discharged by the at least one spraying assembly (2), the separation assembly (32) is configured to heat the spraying solution to form a concentrated solution and net steam, and the concentrated solution and the net steam are introduced into the preheating assembly (31) to heat the spraying solution in the preheating assembly (31).

Description

A spray cooling system

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202311579001.1 and application date November 24, 2023, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the technical field of flue gas purification, and in particular to a spray cooling system. Background Art

[0004] In the field of integrated removal technology for low-temperature flue gas pollutants, calcium chloride solution is generally used to directly exchange heat with the flue gas in the spray section of the spray tower in the sub-zero temperature zone. However, as the operating time increases, the calcium chloride solution will be diluted by the moisture in the flue gas, causing the freezing point of the calcium chloride solution to increase. Therefore, the initial concentration of calcium chloride solution needs to be supplemented or replaced, resulting in increased consumption of calcium chloride solution and increased operating costs.

[0005] To prevent the freezing point of calcium chloride solution from rising after prolonged use, the related art uses a concentration process for the diluted calcium chloride solution: the diluted calcium chloride solution is directly heated to convert the water in the calcium chloride solution into water vapor and discharge it, thereby concentrating the calcium chloride solution. However, this method of concentrating the solution by heating the solution not only consumes a large amount of energy, such as electricity, but also results in a large amount of energy waste during the concentration process. Summary of the Invention

[0006] The present application aims to solve, at least to some extent, one of the technical problems in the related art. To this end, the present application proposes a spray cooling system that, during the concentration of a spray solution, repeatedly and fully utilizes the energy generated during the concentration process, thereby avoiding energy waste and reducing production costs.

[0007] The spray cooling system of this application includes:

[0008] A spray cooling tower, wherein the spray cooling tower has a flue gas inlet and a flue gas outlet, and the spray cooling tower has a plurality of spray zones arranged in sequence along the flue gas flow direction;

[0009] a plurality of spray assemblies, each of the plurality of spray assemblies corresponding to each of the plurality of spray zones, the spray assemblies being configured to spray a spray solution into the spray zones to cool the flue gas entering the spray cooling tower from the flue gas inlet and sequentially passing through the plurality of spray zones into low-temperature flue gas below room temperature;

[0010] A concentration device, the concentration device comprising a preheating component and a separation component, the preheating component being connected to at least one of the plurality of spray components and being used to preheat a portion of the spray solution discharged by the at least one spray component,

[0011] The separation component has a spray solution inlet, a starting steam inlet, a concentrated solution outlet and a clean steam outlet. The spray solution inlet is connected to the preheating component for passing the preheated spray solution. The starting steam inlet is used to pass raw steam. The raw steam is used to heat the spray solution passed into the separation component so that the heated spray solution forms a concentrated solution and clean steam. The concentrated solution outlet is connected to the preheating component so that the concentrated solution passes into the preheating component through the concentrated solution outlet to heat the spray solution in the preheating component. The clean steam outlet is connected to the preheating component so that the clean steam passes into the preheating component through the clean steam outlet to heat the spray solution in the preheating component.

[0012] The spray cooling system of the present application can utilize a concentration device to heat the spray solution and separate it into a concentrated solution and clean steam, and use the discharged concentrated solution and clean steam to preheat the spray solution therein twice in a preheating component, respectively, thereby increasing the temperature of the spray solution before it enters the separation component, thereby reducing the amount of raw steam entering the separation component and reducing energy consumption.

[0013] In some embodiments, the separation component also includes a non-condensable gas outlet, which is connected to the preheating component. The non-condensable gas formed after the spray solution in the separation component is heated is passed into the preheating component through the non-condensable gas outlet to heat the spray solution in the preheating component.

[0014] The spray cooling system of the present application can also separate the non-condensable gas that is insoluble in water in the spray solution by using a separation component, and the discharged non-condensable gas can also be passed into the preheating component to preheat the preheating component for a third time, further improving energy utilization and avoiding energy waste.

[0015] In some embodiments, the preheating assembly includes a first preheater, a second preheater, and a third preheater connected in sequence, the first preheater is connected to the at least one spray assembly so that part of the spray solution passes from the at least one spray assembly into the first preheater, and the concentrated solution outlet, the net steam outlet, and the non-condensable gas outlet are correspondingly connected to the first preheater, the second preheater, and the third preheater so as to heat the spray solution in the first preheater, the second preheater, and the third preheater.

[0016] In the spray cooling system of the present application, the separation component heats the spray solution and produces a concentrated solution, clean steam and non-condensable gas. The concentrated solution, clean steam and non-condensable gas indirectly preheat the spray solution in the first preheater, the second preheater and the third preheater step by step. While ensuring full utilization of energy, the concentrated solution, clean steam and non-condensable gas after heat exchange can be collected separately for use in other equipment.

[0017] In some embodiments, the first preheater has a first heating inlet, a first solution inlet and a first solution outlet, the first heating inlet is connected to the concentrated solution outlet, the first solution inlet is connected to the at least one spray assembly, and the first solution outlet is connected to the at least one spray assembly so that the concentrated solution is mixed with the spray solution in the at least one spray assembly; the second preheater has a second heating inlet, a second solution inlet and a second solution outlet, the second solution inlet is connected to the first solution outlet, and the second heating inlet is connected to the net steam outlet; the third preheater has a third heating inlet, a third solution inlet and a third solution outlet, the third solution inlet is connected to the second solution outlet, and the third heating inlet is connected to the non-condensable gas outlet.

[0018] The spray cooling system of the present application utilizes a concentrated solution to preheat the spray solution in the first preheater for the first time, utilizes clean steam to preheat the spray solution in the second preheater for the second time, and utilizes non-condensable gas to preheat the spray solution in the third preheater for the third time, thereby ensuring heat exchange efficiency and achieving a better preheating effect. In other words, in the first preheater, the concentrated solution is used to exchange heat with the spray solution. Because both the heat exchange source and the heat exchanged source are liquids, they have strong heat transfer capabilities and good heat exchange effects. Therefore, in the first preheater, the spray solution achieves a better preheating effect.

[0019] In some embodiments, the spray cooling system of the present application further includes a steam compressor having a steam inlet and a steam outlet, wherein the steam inlet is connected to the net steam outlet, and the steam outlet is connected to the second heating inlet.

[0020] The spray cooling system of the present application can use the clean steam discharged from the steam outlet to drive the steam compressor, and can convert the energy in the clean steam into mechanical energy, so that it can be used for other equipment. In addition, the steam discharged from the steam compressor is passed into the second preheater and preheats the spray solution for a second time, further realizing the reuse of steam and avoiding energy waste.

[0021] In some embodiments, the separation component further has a drug addition inlet, which is used to introduce a neutralizing agent into the separation component to adjust the pH value of the spray solution in the separation component.

[0022] In the spray cooling system of the present application, the spray solution after heat exchange in the spray cooling tower can absorb elements such as sulfur and nitrogen in the flue gas to make the spray solution acidic. However, in the separation component, the water in the spray solution is evaporated in large quantities, which further increases the acidity of the concentrated solution. Therefore, it is necessary to add medicine to the spray solution in the separation component to neutralize the pH value of the spray solution to prevent the concentrated solution from corroding the conveying equipment.

[0023] In some embodiments, the plurality of spray zones include a spray zone located most downstream in the direction of flue gas flow, the spray assembly corresponding to the most downstream spray zone is the most downstream spray assembly, and the preheating assembly is connected to the most downstream spray assembly.

[0024] In the spray cooling system of the present application, the spray area located at the most downstream can spray and cool the flue gas to below room temperature. As a result, the temperature of the spray solution discharged from the spray area is higher than the temperature of the discharged flue gas. Then, the preheating component can be used to preheat the spray solution three times, realizing energy recycling while ensuring a good preheating effect.

[0025] In some embodiments, the first preheater is used to heat the spray solution in the first preheater to 30°C-34°C; the second preheater is used to heat the spray solution in the second preheater to 48°C-53°C; and the third preheater is used to heat the spray solution in the third preheater to 55°C-59°C.

[0026] The spray cooling system of the present application utilizes indirect heat exchange between liquid (concentrated solution) and liquid (spray solution) in the first preheater, which can significantly increase the temperature of the spray solution and improve the heat exchange effect. It is then preheated in the second and third preheaters in sequence to achieve step preheating and fully utilize energy.

[0027] In some embodiments, the volume of the spray solution in the spray assembly is Q, the volume of the partial spray solution is Q1, and Q1=(1%-2%)Q.

[0028] In the spray cooling system of the present application, the volume of the spray solution in the spray cooling tower is large, and it is difficult to concentrate all of it. Therefore, in some embodiments, (1%-2%) of the spray solution is concentrated, and then the concentrated solution is mixed with the spray solution after spraying to obtain a spray solution with a concentration equivalent to that of the spray solution before spraying, thereby achieving continuous recycling of the spray solution.

[0029] In some embodiments, the volume of the concentrated solution in the separation assembly is V and satisfies 65% ≤ V / Q1 ≤ 75%. In other words, the spray cooling system of the present application uses the separation assembly to concentrate the extracted spray solution to produce a concentrated solution that is 65%-75% of the volume of the spray solution. After the concentrated solution is mixed with the spray solution in the spray assembly, the concentration of the mixed spray solution can be made equivalent to the concentration of the spray solution before spraying. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is a schematic structural diagram of a spray cooling system according to an embodiment of the present application.

[0031] FIG2 is a schematic structural diagram of a concentration device of a spray cooling system according to an embodiment of the present application.

[0032] Reference numerals:

[0033] Spray cooling tower 1; first-level spray area 11; second-level spray area 12; third-level spray area 13; fourth-level spray area 14; flue gas inlet 15; flue gas outlet 16;

[0034] Spray assembly 2; first-level spray assembly 21; second-level spray assembly 22; third-level spray assembly 23; fourth-level spray assembly 24; spray solution outlet 231; spray solution inlet 232;

[0035] Concentration device 3;

[0036] Preheating assembly 31; first preheater 311; first heating inlet 3111; first solution inlet 3112; first solution outlet 3113; first heating outlet 3114; second preheater 312; second heating inlet 3121; second solution inlet 3122; second solution outlet 3123; third preheater 313; third heating inlet 3131; third solution inlet 3132; third solution outlet 3133;

[0037] Separation component 32; start steam inlet 321; concentrated solution outlet 322; clean steam outlet 323; non-condensable gas outlet 324; dosing inlet 325;

[0038] Steam compressor 4. Modes for Carrying Out the Invention

[0039] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present application, but should not be understood as limiting the present application.

[0040] As shown in FIG. 1 and FIG. 2 , the spray cooling system of the embodiment of the present application includes: a spray cooling tower 1 , a concentration device 3 and a plurality of spray components 2 .

[0041] The spray cooling tower 1 has a flue gas inlet 15 and a flue gas outlet 16. The spray cooling tower 1 includes multiple spray zones spaced sequentially along the flue gas flow direction. Multiple spray assemblies 2 correspond to each of the spray zones and are used to spray a spray solution into the spray zones, cooling the flue gas that enters the spray cooling tower from the flue gas inlet and flows through the multiple spray zones to a low-temperature flue gas below room temperature. The low-temperature flue gas is then supplied to the adsorption tower for low-temperature adsorption, achieving near-zero emissions.

[0042] In some embodiments, as shown in Figures 1 and 2 , a flue gas inlet 15 is located at the bottom of the spray cooling tower 1, and a flue gas outlet 16 is located at the top of the spray cooling tower 1, so that flue gas passing through the flue gas inlet 15 can flow in a bottom-up direction. A recyclable spray solution is provided between a spray assembly 2 and its corresponding spray zone. Specifically, when flue gas passes through the spray zone, the spray assembly 2 corresponding to the spray zone can spray the spray solution into the spray zone and directly exchange heat with the flue gas. After heat exchange, the spray solution can then flow from the spray zone to the spray assembly 2, thereby achieving recycling of the spray solution.

[0043] It is understood that, depending on actual operating conditions, a spray solution below 0°C, such as a calcium chloride solution, is used in the spray assembly 2 so that the flue gas temperature can be reduced to below 0°C after the spray solution is introduced into the spray zone. Of course, other solutions that do not condense below 0°C can also be used as the spray solution. The spray assembly 2 includes a refrigeration device (such as a refrigerator) to cool the spray solution after heat exchange. The cooled spray solution is then introduced into the spray zone for spray cooling.

[0044] In some embodiments, multiple spray zones are used to reduce the flue gas temperature to -20°C to -5°C.

[0045] Through research, the inventors discovered that lower flue gas temperatures are more beneficial for adsorption purification. However, excessively low flue gas temperatures lead to complex equipment structures and increased energy consumption. For example, these temperatures require insulation in the adsorption tower and piping, requiring high sealing requirements, which increases costs. Furthermore, excessively low temperatures can easily lead to condensation in the adsorption tower, causing the adsorbent to stick and clog, thus affecting adsorption. Therefore, cooling the flue gas to a temperature between -20°C and -5°C is beneficial.

[0046] As shown in Figures 1 and 2, the concentration device 3 includes a preheating component 31 and a separation component 32. The preheating component 31 is connected to at least one spray component 2 among the multiple spray components 2. The preheating component 31 is used to preheat part of the spray solution discharged from at least one spray component 2. The separation component 32 has a spray solution inlet, a starting steam inlet 321, a concentrated solution outlet 322 and a clean steam outlet 323. The spray solution inlet is connected to the preheating component 31 for passing the preheated spray solution. The starting steam inlet 321 is used to pass raw steam, which is used to heat the spray solution passed into the separation component 32 so that the heated spray solution forms a concentrated solution and clean steam. The concentrated solution outlet 322 is connected to the preheating component 31 so that the concentrated solution passes into the preheating component 31 through the concentrated solution outlet 322 to heat the spray solution in the preheating component 31. The clean steam outlet 323 is connected to the preheating component 31 so that the clean steam passes into the preheating component 31 through the clean steam outlet 323 to heat the spray solution in the preheating component 31.

[0047] It is understood that the flue gas entering the flue gas inlet 15 is at a relatively high temperature (approximately 100°C). As the flue gas cools within the spray tower cooling tower, the flue gas temperature decreases and the remaining water vapor in the flue gas liquefies. Consequently, the spray solution mixes with the liquefied water vapor after spraying, diluting the spray solution within the spray area. This increases the freezing point of the spray solution and makes it more susceptible to condensation. Therefore, the concentration device 3 is used to concentrate the diluted spray solution and mix the concentrated solution with the spray solution in the spray assembly 2, so that the concentration of the mixed spray solution is comparable to that of the spray solution before heat exchange with the flue gas.

[0048] In other words, the spray cooling system of the embodiment of the present application utilizes the concentration device 3 to heat the spray solution and separate the concentrated solution and clean steam, and uses the discharged concentrated solution and clean steam to preheat the spray solution therein twice in the preheating component 31, thereby increasing the temperature of the spray solution before it enters the separation component 32, thereby reducing the amount of raw steam entering the separation component 32, thereby reducing production energy consumption.

[0049] In some embodiments, in the spray cooling system of the embodiment of the present application, indirect heat exchange is adopted in the preheating component 31, which can avoid the concentrated solution and the clean steam from mixing with the spray solution in the preheating component 31, and is also conducive to the secondary collection of the concentrated solution and the clean steam after heat exchange.

[0050] In some embodiments, the separation component 32 also includes a non-condensable gas outlet 324, which is connected to the preheating component 31. The non-condensable gas formed after the spray solution in the separation component 32 is heated is passed into the preheating component 31 through the non-condensable gas outlet 324 to heat the spray solution in the preheating component 31.

[0051] It is understood that, as shown in Figures 1 and 2, separation assembly 32 includes a separator. The spray solution preheated by preheating assembly 31 can be passed into the separator. The spray solution in the separator is heated using live steam to evaporate the spray solution and form a concentrated solution and a mixed gas (including pure steam and non-condensable gases). Separation assembly 32 also includes a condenser. That is, before the non-condensable gas is discharged from non-condensable gas outlet 324, the evaporated gas must be passed into the condenser to condense the gas into condensed water. The portion of the gas that is not fully condensed into condensed water is non-condensable gas, which includes ammonia, etc.

[0052] That is to say, the non-condensable gas separated from the condenser still has a certain amount of heat. Therefore, passing the non-condensable gas into the preheating component 31 can also achieve preheating of the spray solution in the preheating component 31 .

[0053] It should be noted that the separator can be a flash tank. Using live steam to heat the spray solution to approximately 90°C before passing it into the separator will lower the boiling point of the spray solution in the separator, causing it to boil and vaporize rapidly, thereby reducing the amount of live steam used. Of course, the separator can also be a tank with an internal cavity at standard atmospheric pressure. In this case, using live steam would require heating the spray solution to 100°C to achieve boiling and vaporization.

[0054] Therefore, the spray cooling system of the embodiment of the present application can also separate the non-condensable gas that is insoluble in water in the spray solution using the separation component 32, and the discharged non-condensable gas can also be passed into the preheating component 31 to preheat the preheating component 31 for the third time, further improving energy utilization and avoiding energy waste.

[0055] In some embodiments, the preheating component 31 includes a first preheater 311, a second preheater 312 and a third preheater 313 connected in sequence, the first preheater 311 is connected to at least one spray component 2 so that part of the spray solution flows into the first preheater 311 from at least one spray component 2, and the concentrated solution outlet 322, the net steam outlet 323 and the non-condensable gas outlet 324 are correspondingly connected to the first preheater 311, the second preheater 312 and the third preheater 313 so as to heat the spray solution in the first preheater 311, the second preheater 312 and the third preheater 313.

[0056] It is understood that the first preheater 311 can be connected to one spray assembly 2, or the first preheater 311 can be connected to multiple spray assemblies 2. In some embodiments, as shown in Figures 1 and 2, the first preheater 311 is connected to one spray assembly 2. The concentrated solution outlet 322 can be connected to any one of the first preheater 311, the second preheater 312, and the third preheater 313, and the net steam outlet 323 and the non-condensable gas outlet 324 are respectively connected to the other two preheaters. In some embodiments, as shown in Figures 1 and 2, the concentrated solution outlet 322 is connected to the first preheater 311, the net steam outlet 323 is connected to the second preheater 312, and the non-condensable gas outlet 324 is connected to the third preheater 313.

[0057] That is to say, the separation component 32 of the spray cooling system of the embodiment of the present application heats the spray solution and produces a concentrated solution, clean steam and non-condensable gas. The concentrated solution, clean steam and non-condensable gas indirectly preheat the spray solution in the first preheater 311, the second preheater 312 and the third preheater 313 step by step. While ensuring full utilization of energy, the concentrated solution, clean steam and non-condensable gas after heat exchange can also be collected separately for use in other equipment.

[0058] In some embodiments, the first preheater 311 has a first heating inlet 3111, a first solution inlet 3112 and a first solution outlet 3113, the first heating inlet 3111 is connected to the concentrated solution outlet 322, the first solution inlet 3112 is connected to at least one spray assembly 2, and the first solution outlet 3113 is connected to at least one spray assembly 2 so that the concentrated solution is mixed with the spray solution in at least one spray assembly 2; the second preheater 312 has a second heating inlet 3121, a second solution inlet 3122 and a second solution outlet 3123, the second solution inlet 3122 is connected to the first solution outlet 3113, and the second heating inlet 3121 is connected to the net steam outlet 323; the third preheater 313 has a third heating inlet 3131, a third solution inlet 3132 and a third solution outlet 3133, the third solution inlet 3132 is connected to the second solution outlet 3123, and the third heating inlet 3131 is connected to the non-condensable gas outlet 324.

[0059] It can be understood that the concentrated solution discharged from the concentrated solution outlet 322 can flow into the first preheater 311 through the pipeline and exchange heat with the spray solution in the first preheater 311 to achieve the first preheating; the clean steam is passed into the second preheater 312 through the pipeline and exchanges heat with the spray solution in the second preheater 312 to achieve the second preheating; the non-condensable gas is passed into the third preheater 313 through the pipeline and exchanges heat with the spray solution in the third preheater 313 to achieve the third preheating.

[0060] In some embodiments, as shown in Figures 1 and 2, a spray solution outlet 231 and a spray solution inlet 232 are provided on the spray assembly 2. Along the circulation direction of the spray solution in the spray assembly 2, the spray solution outlet is located upstream of the spray solution inlet, and the spray solution outlet is connected to the first solution inlet 3112. The first solution outlet 3114 is connected to the spray solution inlet, so that the concentrated solution after heat exchange in the first preheater 311 can be passed into the spray assembly 2, thereby achieving mixing of the concentrated solution with the spray solution therein in the spray assembly 2 to increase the concentration of the spray solution in the spray assembly 2.

[0061] It should be noted that the first preheater 311 , the second preheater 312 and the third preheater 313 all use indirect heat exchange to perform heat exchange.

[0062] In other words, the spray cooling system of the present embodiment utilizes concentrated solution outlet 322 to discharge concentrated solution to preheat the spray solution in the first preheater 311 for the first time, utilizes clean steam to preheat the spray solution in the second preheater 312 for the second time, and utilizes non-condensable gas to preheat the spray solution in the third preheater 313 for the third time, thereby ensuring heat exchange efficiency and achieving a better preheating effect. In other words, in the first preheater 311, the concentrated solution is used to exchange heat with the spray solution. Because both the heat exchange source and the heat exchanged source are liquids, they have strong heat transfer capabilities and good heat exchange effects. Therefore, in the first preheater 311, the spray solution achieves a better preheating effect.

[0063] In some embodiments, a liquid concentration sensor (not shown) and an electrically controlled valve (not shown) are provided upstream of the spray solution outlet 231. The liquid concentration sensor is used to detect the concentration of the spray solution upstream of the spray solution outlet 231, and the liquid concentration sensor is electrically connected to the electrically controlled valve to transmit a control signal to the electrically controlled valve. Specifically, the liquid sensor detects the concentration of the spray solution. If the concentration of the spray solution does not reach a preset concentration, the electrically controlled valve is closed, and the spray solution is cooled by the refrigeration equipment before being passed into the spray zone for spray cooling. If the concentration of the spray solution reaches the preset concentration, the electrically controlled valve is opened, and the spray solution is concentrated by the concentration device 3, passed into the spray assembly 2 for mixing with the spray solution, and then cooled by the refrigeration equipment before being passed into the spray zone for spray cooling.

[0064] In some embodiments, the spray cooling system of the embodiment of the present application further includes a steam compressor 4 , which has a steam inlet and a steam outlet. The steam inlet is connected to the net steam outlet 323 , and the steam outlet is connected to the second heating inlet 3121 .

[0065] The spray cooling system of the embodiment of the present application can use the clean steam discharged from the steam outlet to drive the steam compressor 4, and can convert the energy in the clean steam into mechanical energy, so that it can be used for other equipment. In addition, the steam discharged from the steam compressor is passed into the second preheater 312 and preheats the spray solution for a second time, further realizing the reuse of steam and avoiding energy waste.

[0066] In some embodiments, the separation component 32 further has a drug addition inlet 325 , which is used to introduce a neutralizing agent into the separation component 32 to adjust the pH value of the spray solution in the separation component 32 .

[0067] The spray solution after heat exchange in the spray cooling tower 1 of the spray cooling system of the embodiment of the present application can absorb elements such as sulfur and nitrogen in the flue gas to make the spray solution acidic. In the separation component 32, since a large amount of water in the spray solution is evaporated, the acidity of the concentrated solution is further enhanced. Therefore, it is necessary to add medicine to the spray solution in the separation component 32 to neutralize its pH value to prevent the concentrated solution from corroding the conveying equipment.

[0068] In some embodiments, the multiple spray areas include a spray area located most downstream in the direction of flue gas flow, the spray assembly 2 corresponding to the most downstream spray area is the most downstream spray assembly 2, and the preheating assembly 31 is connected to the most downstream spray assembly 2.

[0069] In some embodiments, as shown in Figures 1 and 2, there are four spray areas, namely, from bottom to top, the first-level spray area 11, the second-level spray area 12, the third-level spray area 13 and the fourth-level spray area 14, and there are also four spray components 2, namely, the first-level spray component 21, the second-level spray component 22, the third-level spray component 23 and the fourth-level spray component 24, and the preheating component 31 is connected to the fourth-level spray component 24.

[0070] It can be understood that in the spray cooling tower 1, the temperature of the spray zone at the top is the lowest compared to the temperature of other spray zones, so the temperature of the spray solution used is also the lowest. When the flue gas spray needs to be cooled to below 0°C, in order to prevent the spray solution from condensing, a solution with a higher freezing point needs to be used, such as a 20% concentration of calcium chloride solution.

[0071] It should be noted that the first-stage spray assembly 21, the second-stage spray assembly 22, the third-stage spray assembly 23 and the fourth-stage spray assembly 24 can use refrigerators to cool the spray solutions discharged from their corresponding spray areas, so that the cooled spray solutions can be re-introduced into the spray areas for heat exchange with the flue gas, thereby realizing the recycling of the spray solutions.

[0072] In the spray cooling system of the embodiment of the present application, the spray area located at the most downstream can spray and cool the flue gas to below room temperature. As a result, the temperature of the spray solution discharged from the spray area is higher than the temperature of the discharged flue gas. Then, the preheating component 31 can be used to preheat the spray solution three times, thereby achieving energy recycling and ensuring a good preheating effect.

[0073] In some embodiments, the first preheater 311 is used to heat the spray solution in the first preheater 311 to 30°C-34°C; the second preheater 312 is used to heat the spray solution in the second preheater 312 to 48°C-53°C; the third preheater 313 is used to heat the spray solution in the third preheater 313 to 55°C-59°C.

[0074] It can be understood that, taking the example of cooling the flue gas spray to below 0°C, since the spray solution required by the fourth-stage spray zone 14 is relatively low, the spray solution after heat exchange with the flue gas is also close to 0°C, then when the spray solution after heat exchange is passed into the first preheater 311, the concentrated solution is used to exchange heat with the spray solution, which can quickly increase the temperature of the spray solution.

[0075] The spray cooling system of the embodiment of the present application utilizes indirect heat exchange between liquid (concentrated solution) and liquid (spray solution) in the first preheater 311, which can significantly increase the temperature of the spray solution and improve the heat exchange effect. It is then preheated in sequence through the second preheater 312 and the third preheater 313 to achieve step preheating and fully utilize energy.

[0076] In some embodiments, the volume of the spray solution in the spray assembly 2 is Q, the volume of a portion of the spray solution is Q1, and Q1=(1%-2%)Q.

[0077] The volume of the spray solution in the spray cooling tower 1 in the spray cooling system of the embodiment of the present application is large, and it is difficult to concentrate all of it. Therefore, in some embodiments, (1%-2%) of the spray solution is concentrated, and then the concentrated solution is mixed with the spray solution after spraying to obtain a spray solution with a concentration equivalent to that of the spray solution before spraying, thereby achieving continuous recycling of the spray solution.

[0078] In some embodiments, the volume of the concentrated solution in the separation assembly 32 is V and satisfies 65% ≤ V / Q1 ≤ 75%. In other words, the spray cooling system of the present application uses the separation assembly 32 to concentrate the extracted spray solution to produce a concentrated solution that is 65%-75% of the volume of the spray solution. After the concentrated solution is mixed with the spray solution in the spray assembly 2, the concentration of the mixed spray solution can be made equivalent to the concentration of the spray solution before spraying.

[0079] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0080] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0081] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0082] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0083] In this application, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0084] Although the above embodiments have been shown and described, it is understood that the above embodiments are illustrative and cannot be understood as limitations on the present application. Changes, modifications, substitutions and variations of the above embodiments made by ordinary technicians in this field are all within the scope of protection of the present application.

Claims

1. A spray cooling system, comprising: A spray cooling tower, wherein the spray cooling tower has a smoke inlet and a smoke outlet, and the spray cooling tower has a plurality of spray zones arranged in sequence and at intervals along the direction of smoke flow; A plurality of spray assemblies, each of the plurality of spray assemblies corresponds to the plurality of spray zones one by one, and the spray assemblies are used to spray a spray solution into the spray zones to cool the flue gas that enters the spray cooling tower from the flue gas inlet and sequentially flows through the plurality of spray zones into low-temperature flue gas below room temperature; A concentration device, the concentration device comprising a preheating component and a separation component, the preheating component is connected to at least one of the plurality of spray components, and is used to preheat a portion of the spray solution discharged from the at least one spray component, The separation component has a spray solution inlet, a start-up steam inlet, a concentrated solution outlet and a clean steam outlet. The spray solution inlet is connected to the preheating component for passing the preheated spray solution. The start-up steam inlet is used to pass raw steam. The raw steam is used to heat the spray solution passed into the separation component so that the heated spray solution forms a concentrated solution and clean steam. The concentrated solution outlet is connected to the preheating component so that the concentrated solution passes into the preheating component through the concentrated solution outlet to heat the spray solution in the preheating component. The clean steam outlet is connected to the preheating component so that the clean steam passes into the preheating component through the clean steam outlet to heat the spray solution in the preheating component.

2. The spray cooling system according to claim 1, wherein: The separation component also includes a non-condensable gas outlet, which is connected to the preheating component. The non-condensable gas formed after the spray solution in the separation component is heated is passed into the preheating component through the non-condensable gas outlet to heat the spray solution in the preheating component.

3. The spray cooling system according to claim 2, wherein: The preheating assembly comprises a first preheater, a second preheater and a third preheater which are connected in sequence, wherein the first preheater is connected to the at least one spray assembly so that the part of the spray solution passes from the at least one spray assembly into the first preheater, The concentrated solution outlet, the clean steam outlet and the non-condensable gas outlet are connected to the first preheater, the second preheater and the third preheater respectively so as to heat the spray solution in the first preheater, the second preheater and the third preheater.

4. The spray cooling system according to claim 3, wherein: The first preheater has a first heating inlet, a first solution inlet and a first solution outlet, the first heating inlet is in communication with the concentrated solution outlet, the first solution inlet is in communication with the at least one spray assembly, and the first solution outlet is connected to the at least one spray assembly to mix the concentrated solution with the spray solution in the at least one spray assembly; The second preheater has a second heating inlet, a second solution inlet and a second solution outlet, the second solution inlet is connected to the first solution outlet, and the second heating inlet is connected to the net steam outlet; The third preheater has a third heating inlet, a third solution inlet and a third solution outlet. The third solution inlet is communicated with the second solution outlet, and the third heating inlet is communicated with the non-condensable gas outlet.

5. The spray cooling system according to claim 4, further comprising a steam compressor having a steam inlet and a steam outlet, wherein the steam inlet is connected to the net steam outlet, and the steam outlet is connected to the second heating inlet.

6. The spray cooling system according to claim 5, wherein: The separation component also has a drug addition inlet, which is used to introduce a neutralizing agent into the separation component to adjust the pH value of the spray solution in the separation component.

7. The spray cooling system according to any one of claims 3 to 6, wherein: The plurality of spray zones include a spray zone located most downstream in the flue gas flow direction, the spray assembly corresponding to the most downstream spray zone is the most downstream spray assembly, and the preheating assembly is connected to the most downstream spray assembly.

8. The spray cooling system according to claim 7, wherein: The first preheater is used to heat the spray solution in the first preheater to 30° C.-34° C.; The second preheater is used to heat the spray solution in the second preheater to 48° C.-53° C.; The third preheater is used to heat the spray solution in the third preheater to 55°C-59°C.

9. The spray cooling system according to any one of claims 1 to 6, wherein: The volume of the spray solution in the spray assembly is Q, the volume of the partial spray solution is Q1, and Q1=(1%-2%)Q.

10. The spray cooling system according to claim 9, wherein: The volume of the concentrated solution in the separation component is V and satisfies 65%≤V / Q1≤75%.

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