Self-cleaning self-sustaining one-step purification equipment and purification process

Abstract

The present application discloses a self-cleaning self-sustaining one-step purification device and a purification process, which are used for purifying flue gas containing water vapor, ammonia, and acidic pollutants; the purification device includes: a box body, which has a flue gas inlet and a flue gas outlet, and a flue gas passage formed from the flue gas inlet to the flue gas outlet; a low-temperature condensation module, which is connected to a cooling water inlet and a cooling water return port; the low-temperature condensation module cools and condenses the flue gas entering the flue gas purification passage from the flue gas inlet, condenses the water vapor into condensed water, and ammonia and acidic pollutants dissolve in the condensed water and undergo an acid-base neutralization reaction in the condensed water to form non-volatile salts that are easily soluble in the condensed water; a spray washing device, which is arranged at the flue gas inlet and is used for spraying cleaning water at the flue gas inlet, and the cleaning water quickly enters the low-temperature condensation module along with the flue gas and wind to wash the surface of the water pipes of the cooling water pipe bundle.

Description

Technical Field

[0001] This application relates to the technical field of environmental protection equipment. Specifically, it relates to a self-cleaning self-sustaining one-step purification equipment and a purification process. Background Art

[0002] Currently, the vast majority of NOx treatment technologies for cement kiln tail gas still use ammonia source (such as ammonia water, urea, etc.) reductants. Due to the limitation of denitrification efficiency, there are more or less problems of secondary air pollution caused by excessive use of reductants resulting in ammonia escape.

[0003] The known prior art discloses a recovery and circulation system for escaped ammonia in cement kiln ammonia-based denitrification tail gas and its control method. The system includes a spray tower, a heat exchanger, a storage tank, and a receiving tank. The denitrification tail gas in the flue is transported by a fan to the heat exchanger for cooling, and then enters the tower from the bottom of the spray tower; then the absorbent in the storage tank is pumped by a pump to the spray tower to contact and react with the upward denitrification tail gas to obtain ammonia-containing absorbent and deammoniated tail gas; after that, the ammonia-containing absorbent flows into the receiving tank, and the supernatant after precipitation is pumped and recycled into the spray tower to contact the denitrification tail gas repeatedly until a saturated ammonia absorbent is formed; and the slurry settled at the bottom of the receiving tank is regularly pumped to the cement kiln through a pump; the saturated ammonia absorbent is pumped to an ammonia water storage tank and mixed with ammonia water for denitrification reaction. Ammonium salts decompose ammonia during the SNCR process as part of the ammonia source to react with nitrogen oxides, thereby realizing the recycling of escaped ammonia.

[0004] Although this prior art can solve the problem of ammonia escape, its deammoniation efficiency is low, the equipment volume is large, and the cost is high. The specific analysis is as follows:

[0005] 1. This prior art requires heat exchange first, then spraying, then collection, and then recycling for tail gas treatment. The multiple treatment steps result in a complex deammoniation process and low deammoniation efficiency.

[0006] 2. Before the tail gas enters the spray tower, the heat exchanger in this prior art can only achieve limited cooling. On the one hand, because high-temperature ammonia is easy to volatilize and is not conducive to being absorbed in the spray tower, cooling the high-temperature tail gas through the pre-positioned heat exchanger can improve the absorption efficiency of ammonia in the spray tower. On the other hand, the pre-cooling treatment through the heat exchanger can reduce the working pressure of the spray tower, that is, reduce the spray water volume of the spray tower. However, when using a spray tower to absorb ammonia, the spray water volume is still huge, which also causes a large receiving volume in the subsequent receiving tank of this prior art, a large equipment volume, and a large processing volume for the ammonia-containing absorbent to be recycled into the spray tower.

[0007] 3. The ammonia-containing absorbent flowing into the receiving tank in this prior art requires a long time for precipitation, which further reduces the deammoniation efficiency of this prior art.

[0008] Therefore, overall, the existing ammonia escape recovery and circulation system has problems such as complex processes, low ammonia removal efficiency, large equipment volume, high costs, and a large amount of wastewater treatment. Summary of the Invention

[0009] Therefore, the technical problem to be solved by the present invention is to overcome the problems of complex processes, low ammonia removal efficiency, large equipment volume, and high costs existing in the existing ammonia escape purification equipment, so as to provide a self-cleaning self-sustaining one-step purification equipment and purification process.

[0010] To achieve the above object, the first aspect of the present application provides a self-cleaning self-sustaining one-step purification equipment for purifying flue gas containing water vapor, ammonia, and acidic pollutants; the purification equipment includes:

[0011] A box body having a flue gas inlet and a flue gas outlet, and a flue gas passage formed from the flue gas inlet to the flue gas outlet;

[0012] A low-temperature condensation module communicating with a cooling water inlet and a cooling water return port; the low-temperature condensation module includes cooling water pipe bundles vertically arranged and arranged in an array in the flue gas passage and end joint assemblies connected to the upper and lower ends of the cooling water pipe bundles, and the end joint assemblies together with the cooling water pipe bundles form a cooling water circulation pipeline for the cooling water to flow from the cooling water inlet to the cooling water return port; the low-temperature condensation module cools and condenses the flue gas entering the flue gas passage from the flue gas inlet, condenses the water vapor into condensed water, and the ammonia and the acidic pollutants dissolve in the condensed water and undergo an acid-base neutralization reaction in the condensed water to form non-volatile salts that are easily soluble in the condensed water;

[0013] A spray washing device provided at the flue gas inlet for spraying cleaning water at the flue gas inlet, and the cleaning water quickly enters the low-temperature condensation module along with the flue gas and wind to wash the surface of the water pipes of the cooling water pipe bundles.

[0014] Optionally, it further includes

[0015] An atomizing device provided at the flue gas inlet for spraying atomized water at the flue gas inlet to increase the water vapor content in the flue gas.

[0016] Optionally, a medicament for ammonia removal and / or desulfurization and / or denitrification is added to the atomized water of the atomizing device.

[0017] Optionally, the cooling water pipe bundles are arranged in a staggered tube bundle array.

[0018] Optionally, the cooling water pipe bundle is divided into a plurality of cooling water pipe groups along the flue gas flow direction. Each cooling water pipe group includes multiple rows of cooling water pipes arranged along the flue gas flow direction. In the multiple rows of cooling water pipes, two adjacent rows of cooling water pipes are arranged staggeredly in the flue gas flow direction and there is no gap between their orthographic projection surfaces.

[0019] Optionally, two adjacent rows of the cooling water pipes and the three cooling water pipes adjacent to them form a cooling water pipe unit arranged in a triangular pattern. The arrangement dimension range of the cooling water pipe unit is as follows:

[0020] C = 1.8A to 2A;

[0021] D = 0.8B to 1.5B;

[0022] Wherein, A is the maximum width dimension of the pipe cross-section; B is the maximum length dimension of the pipe cross-section; C is the center distance dimension of the cross-sections of two adjacent cooling water pipes in the same row; D is the center distance dimension of the cross-sections of adjacent rows of cooling water pipes.

[0023] Optionally, the cooling water pipe is an arc-shaped rhombus cooling water pipe. The arc-shaped rhombus cooling water pipe includes: a cooling water pipe body. The cross-section of the cooling water pipe body is in the shape of an arc-shaped rhombus. The two ends of its short diagonal are respectively arc ends, and the two ends of its long diagonal are respectively pointed ends. The arc ends at the two ends of the short diagonal and the pointed ends at the two ends of the long diagonal are respectively connected by straight edges, and the straight edges are tangent to the arc lines of the arc ends.

[0024] Optionally, the arc ends at the two ends of the short diagonal are concentrically arranged; and / or, the connection line of the midpoints of the arc ends at the two ends of the short diagonal is perpendicular to the connection line of the pointed ends at the two ends of the long diagonal.

[0025] Optionally, the end joint assembly includes an upper end joint assembly and a lower end joint assembly. The upper end joint assembly and the lower end joint assembly are alternately arranged in sequence above and below the cooling water pipe bundle along the flue gas flow direction, and each end joint penetrates through the ends of multiple rows of cooling water pipes to form a parallel pipeline in the cooling water pipe bundle for at least two rows of parallel water flows to flow in the same direction; the upper end joint assembly is an upper water collecting tank, and the lower end joint assembly is a lower water collecting tank. The upper water collecting tank includes multiple upper water collecting tank segments arranged along the flue gas flow direction above the cooling water pipe bundle as the end joints, and the lower water collecting tank includes multiple lower water collecting tank segments arranged along the flue gas flow direction below the cooling water pipe bundle as the end joints. The multiple rows of cooling water pipes penetrated by each water collecting tank segment include a water inlet pipeline and a water outlet pipeline arranged side by side along the flue gas flow direction, and the number of rows of the water inlet pipeline and the water outlet pipeline is the same; one of the upper water collecting tank and the lower water collecting tank further includes a cooling water inlet tank communicated with the cooling water inlet, and the other further includes a cooling water return tank communicated with the cooling water return port. The cooling water inlet tank and the cooling water return tank both penetrate through at least two rows of cooling water pipes correspondingly; the cooling water pipe bundle is divided into multiple cooling water pipe groups along the flue gas flow direction. Each cooling water pipe group includes multiple rows of cooling water pipes arranged along the flue gas flow direction, and each cooling water pipe group corresponds to communicate with a group of the cooling water inlets and the cooling water return ports. The cooling water flows between the multiple cooling water pipe groups are not communicated within the cooling water pipe bundle.

[0026] Optionally, the cooling water flow rate of the cooling water pipe group near the flue gas outlet is less than the cooling water flow rate of the cooling water pipe bundle near the flue gas inlet.

[0027] Optionally, it further includes a cooling water inlet main pipe, and the cooling water inlet main pipe is communicated with each cooling water inlet through a flow regulating valve.

[0028] Optionally, it further includes a condensate water collecting device arranged at the bottom of the low-temperature condensation module for collecting the condensate water, and the condensate water collecting device is connected to a condensate water discharge port.

[0029] The second aspect of the present application provides a purification process using the above self-cleaning self-sustaining one-step purification device, including the following steps:

[0030] Install the self-cleaning self-sustaining one-step purification device at the flue gas outlet of the flue gas emission device to be purified, and seal the flue gas inlet of the self-cleaning self-sustaining one-step purification device with the flue gas outlet of the flue gas emission device to be purified;

[0031] Start the self-cleaning self-sustaining one-step purification equipment. By cooling the flue gas, the water vapor in the flue gas is condensed into condensed water, and the ammonia and acidic pollutants contained in the flue gas dissolve in the condensed water to undergo an acid-base neutralization reaction to form non-volatile salts that are easily soluble in the condensed water.

[0032] Spray cleaning water at the flue gas inlet. The cleaning water flushes the surface of the cooling water pipes of the low-temperature condensation module along with the flue gas to wash away the particulate matter adhered to the pipe surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings forming a part of this application are used to provide a further understanding of this application, making other features, objectives, and advantages of this application more obvious. The schematic embodiments of the drawings of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0034] Figure 1A is a schematic diagram of the self-sustaining one-step purification process flow of the embodiment of this application;

[0035] Figure 1B is a schematic structural diagram (front view) of the self-sustaining one-step purification equipment of the embodiment of this application;

[0036] Figure 1C is Figure 1B the top view of;

[0037] Figure 1D is a structural diagram (front view) of the self-sustaining one-step purification equipment of the embodiment of this application;

[0038] Figure 1E is Figure 1D the side view of;

[0039] Figure 2A is a schematic structural diagram (front view) of the self-sustaining one-step purification equipment (round pipe) of the embodiment of this application;

[0040] Figure 2B is Figure 2A the top view of;

[0041] Figure 2C is a structural diagram (front view) of the self-sustaining one-step purification equipment (round pipe grouped) of the embodiment of this application;

[0042] Figure 2D is Figure 2C the top view of;

[0043] Figure 2E is a three-dimensional view of the self-sustaining one-step purification equipment (round pipe grouped) of the embodiment of this application;

[0044] Figure 3Ais the front view of the low-temperature condensation module (cooling water circulates along grouped water pipes) according to an embodiment of the present application;

[0045] Figure 3B is Figure 3A the top view of;

[0046] Figure 3C is Figure 3A the left view of;

[0047] Figure 3D is the three-dimensional sectional view of the low-temperature condensation module (cooling water circulates along grouped water pipes) according to an embodiment of the present application;

[0048] Figure 4A is the front view of the low-temperature condensation module (cooling water in each straight-through area circulates along grouped water pipes and the cooling water volume is adjustable) according to an embodiment of the present application;

[0049] Figure 4B is Figure 4A the top view of;

[0050] Figure 4C is the left view of the low-temperature condensation module (cooling water in each straight-through area circulates along grouped water pipes and the cooling water volume is adjustable) according to an embodiment of the present application;

[0051] Figure 5A is the front view of the low-temperature condensation module (cooling water in each straight-through area is adjustable) according to an embodiment of the present application;

[0052] Figure 5B is Figure 5A the top view of;

[0053] Figure 5C is Figure 5A the left view of;

[0054] Figure 6A is the front view of the low-temperature condensation module (cooling water in each straight-through area circulates along grouped water pipes and the cooling water volume is adjustable) according to an embodiment of the present application;

[0055] Figure 6B is Figure 6A the top view of;

[0056] Figure 6C is Figure 6A the left view of;

[0057] Figure 6D is the three-dimensional sectional view of the low-temperature condensation module (cooling water in each straight-through area circulates along grouped water pipes and the cooling water volume is adjustable) according to an embodiment of the present application;

[0058] Figure 7A is the top view of the arc rhombus pipe according to an embodiment of the present application;

[0059] Figure 7BIt is the front view of the arc-rhombus tube in the embodiment of the present application;

[0060] Figure 7C It is the sectional view of the arc-rhombus tube in the embodiment of the present application;

[0061] Figure 8 It is the layout diagram of the arc-rhombus tubes in the embodiment of the present application;

[0062] Figure 9A It is the front view of the arc-rhombus tube before tube expansion in the embodiment of the present application;

[0063] Figure 9B It is Figure 9A the partial enlarged view of;

[0064] Figure 10A It is the front view of the arc-rhombus tube after tube expansion in the embodiment of the present application;

[0065] Figure 10B It is Figure 10A the partial enlarged view of;

[0066] Figure 10C It is Figure 10A the top view of;

[0067] Figure 11A It is the front view of the modular self-sustaining one-step purification equipment in the embodiment of the present application;

[0068] Figure 11B It is the top view of the modular self-sustaining one-step purification equipment in the embodiment of the present application;

[0069] Figure 11C It is the left view of the modular self-sustaining one-step purification equipment in the embodiment of the present application;

[0070] Figure 12 It is the schematic structural diagram of the demisting, water collecting and water blocking plate in the embodiment of the present application;

[0071] Figure 13 It is the simplified schematic diagram of convective heat transfer of the low-temperature condensation module in the embodiment of the present application.

[0072] Among them, 1 is a low-temperature condensation module, 101 is a box body, 1011 is an upper box plate, 1012 is a lower box plate, 1013 is a front box plate, 1014 is a rear box plate, 102 is a cooling water pipe bundle, 102a is a cooling water pipe, 1020 is a cooling water pipe body, 1020b is a large arc end, 1020a is a small arc end, 1020c is a straight edge, 1022 is a plug, 103 is a cooling water inlet pipe, 1031 is a flow regulating valve, 1032 is a cooling water inlet main pipe, 1033 is a branch pipe, 104 is a cooling water return pipe, 105 is a round pipe elbow, 2 is a spraying device, 3 is an atomizing device, 4 is a flue gas inlet, 5 is a flue gas outlet, 9 is a water pump, 10 is a condensate discharge port, 11 is an upper water tank, 111 is an upper water tank section, 12 is a lower water tank, 121 is a lower water tank section, 13 is a demisting, water collecting and water blocking plate, 14 is a wire mesh, 15 is a rubber gasket, 16 is a sealant, 17 is an annular groove, 18 is an annular protrusion, 19 is an annular clamping protrusion, 20 is an installation foundation, 21 is a lower joint, 211 is a plug, 212 is a sealing ring, 213 is a joint, 22 is an upper joint, 23 is a condensate collection device, 24 is a cooling water pipe area, 103a is a cooling water inlet, 104a is a cooling water return port, 102b is a water pipe installation hole. Detailed implementation manners

[0073] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0074] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so as to implement the embodiments of this application described herein.

[0075] In this application, the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe this application and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation or be constructed and operated in a specific orientation.

[0076] Moreover, in addition to being able to represent an orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0077] In addition, terms such as "arranged", "provided with", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can be internal communication between two devices, components or parts. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0078] In addition, the meaning of the term "a plurality of" should be two or more.

[0079] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will detail this application with reference to the accompanying drawings and in conjunction with the embodiments.

[0080] Currently, for the treatment of high-temperature flue gas, such as the NOx treatment technology for cement kiln flue gas, the vast majority still uses ammonia source (such as ammonia water, urea, etc.) as the reducing agent. Due to the limitation of the denitrification rate, there is more or less the phenomenon of ammonia escape caused by the excessive use of the reducing agent, which leads to secondary air pollution.

[0081] The known prior art discloses a recovery and recycling system for escaped ammonia in cement kiln ammonia-based denitrification flue gas and its control method. The recovery and recycling system includes a spray tower, a heat exchanger, a storage tank, and a receiving tank. The denitrification flue gas is first transported by a fan to the heat exchanger for cooling, then enters the tower from the bottom of the spray tower, and then the absorbent in the storage tank is pumped to the spray tower by a pump to contact and react with the upward denitrification flue gas, obtaining ammonia-containing absorbent and ammonia-removed flue gas. After that, the ammonia-containing absorbent flows into the receiving tank. After precipitation, the supernatant is pumped and recycled into the spray tower to contact the denitrification flue gas repeatedly until a saturated ammonia absorbent is formed. The slurry settled at the bottom of the receiving tank is regularly pumped to the cement kiln through a pump. The saturated ammonia absorbent is pumped to an ammonia water storage tank and mixed with ammonia water for denitrification reaction. Ammonium salts decompose ammonia during the SNCR (Selective Non-Catalytic Reduction) denitrification process as part of the ammonia source to react with nitrogen oxides, thereby realizing the recycling of escaped ammonia.

[0082] Although this prior art can solve the problem of ammonia escape, it has the defects of low ammonia removal efficiency, large equipment volume, and high cost. The specific analysis is as follows:

[0083] 1. This prior art requires heat exchange, spraying, collection, and recycling for flue gas treatment. The multiple treatment steps lead to a complex ammonia removal process and low ammonia removal efficiency. Moreover, due to the complex process, heat exchangers, spray towers, storage tanks, receiving tanks, etc. are required, resulting in a large overall ammonia removal equipment volume and high cost.

[0084] 2. The prior art discloses that flue gas is first transported to a heat exchanger for cooling. However, from the understanding of the entire technical solution disclosed in the prior art, it can be concluded that the purpose of using a pre-positioned heat exchanger to cool the flue gas in the prior art is, on the one hand, to avoid the situation that volatile high-temperature ammonia is not easily absorbed by the absorbent in the subsequent spray tower process, and by pre-positioning the heat exchanger to cool the high-temperature flue gas to a limited extent, the absorption efficiency of ammonia by the spray tower can be improved. On the other hand, pre-cooling the high-temperature ammonia by the heat exchanger can reduce the working pressure of the spray tower. However, the prior art still uses a spray tower, indicating that the means for solving the ammonia escape problem in the prior art is still the traditional idea of ammonia absorption by the spray tower. Using a spray tower has problems such as a large amount of spray water and a large amount of subsequent sewage purification treatment.

[0085] 3. The ammonia-containing absorbent flowing into the receiving tank requires a long time for precipitation, which further leads to low ammonia removal efficiency in the prior art.

[0086] Therefore, overall, the ammonia escape recovery and circulation system of the prior art has problems such as complex processes, low ammonia removal efficiency, large equipment volume, high cost, and a large amount of wastewater treatment.

[0087] In order to solve the problems of ammonia escape and the complex processes, low ammonia removal efficiency, large equipment volume, high cost, and large amount of wastewater treatment in the above-known prior art deammoniation systems, the present application proposes a self-sustaining one-step purification device and purification method in which the components in the flue gas to be treated can complete physical and chemical reactions by themselves to achieve ammonia absorption (self-sustaining), with a small equipment volume (compact), simple process (one-step method), low cost, and a small amount of wastewater treatment. The purification device provided by the present application can be applied not only to the cement kiln flue gas purification scenario, but also to scenarios such as power plant or coal yard flue gas purification. However, it should be noted that the purification device provided by the present application is only applicable to the purification treatment of flue gas containing water vapor, ammonia, and acidic pollutants.

[0088] As a preferred embodiment of the present application, the purification device is applied to the purification of ammonia-based denitration flue gas from a cement kiln. Currently, ammonia escape generally exists in the flue gas of cement kilns, and the flue gas discharged from cement kilns is high-temperature, containing water vapor, ammonia, and acidic pollutants.

[0089] The purification device of this embodiment has a flue gas inlet 4, a flue gas outlet 5, and a flue gas passage from the flue gas inlet 4 to the flue gas outlet 5. The purification device further includes a low-temperature condensation module 1, and the low-temperature condensation module 1 is arranged in the flue gas passage.

[0090] The main structure of the above purification device can achieve the purification treatment of cement kiln flue gas, and its purification principle is as follows:

[0091] The flue gas from the cement kiln enters the flue gas channel through the flue gas inlet 4 of the purification device. The low-temperature condensation module 1 in the flue gas channel cools and condenses the incoming flue gas, cooling and condensing the water vapor in the flue gas into condensed water (ideally, it is hoped that all the water vapor can be condensed into condensed water). The ammonia and acidic pollutants (such as SO2 and CO2) contained in the flue gas dissolve in the condensed water (physical purification). This is the first layer of purification achieved by the purification device of this application. However, due to the relatively high temperature of the flue gas, the ammonia or acidic pollutants dissolved in the condensed water are likely to volatilize from the condensed water. But the innovation of the purification device of this application is that at the same time, the ammonia and acidic pollutants dissolve in the condensed water and undergo an acid-base neutralization reaction (chemical purification) to generate salts with non-volatile properties that are easily soluble in the condensed water.

[0092] There can be various types of low-temperature condensation modules 1 in the purification device of this application, such as oil-immersed self-cooled low-temperature condensation, refrigerated low-temperature condensation, etc. As a preferred embodiment of this application, the low-temperature condensation module 1 adopts water-cooled low-temperature condensation. The purification device is provided with a cooling water inlet 103a and a cooling water return port 104a, and the low-temperature condensation module 1 is connected to the cooling water inlet 103a and the cooling water return port 104a. The low-temperature condensation module 1 includes a cooling water pipe bundle 102 vertically arranged and arranged in an array in the flue gas channel, and an end joint assembly connected to the upper and lower ends of the cooling water pipe bundle 102. The end joint assembly and the cooling water pipe bundle 102 together form a cooling water circulation pipeline for the cooling water to flow from the cooling water inlet to the cooling water return port.

[0093] After the flue gas enters the flue gas channel from the flue gas inlet 4, it comes into full contact with the surface of the cooling water pipe bundle 102 through which the cooling water is flowing. The water vapor in the flue gas condenses into condensed water on the surface of the water pipes of the cooling water pipe bundle 102 and flows down along the surface of the cooling water pipes to the bottom of the purification device. Since the cooling water in this application does not come into direct contact with the flue gas, the cooling water in the cooling water pipe bundle 102 is not contaminated and can be continuously recycled after being cooled. Moreover, through calculation, the water consumption and consumption of the cooling water in the cooling water pipe bundle 102 are much smaller than the water consumption and consumption in the spray tower in the prior art, and the condensed water purified and recovered by this purification device can completely make up for the evaporated water volume during the cooling process of the cooling water.

[0094] Figure 1BThe working principle of the purification equipment of the present application is shown. The purification equipment of the present application can be used in conjunction with a water pump 9, a cooling water circulation pipeline, and a cooling tower. The water pump 9 provides driving force for the cooling water entering from the cooling water inlet 103a through the cooling water inlet pipeline 103 of the cooling water circulation pipeline. The cooling water flows in the cooling water circulation pipeline and then flows out from the cooling water outlet 104a into the cooling tower. The water in the cooling tower then flows back to the water pump 9 to achieve cooling water circulation. The flue gas of the cement kiln enters the interior of the low-temperature condensation module 1 through the flue gas inlet 4 of the low-temperature condensation module 1 and exchanges heat fully with the cooling water pipe bundle 102. The cooling water pipe bundle 102 quickly cools the flue gas. Importantly, the cooling water pipe bundle 102 condenses the water vapor in the high-temperature flue gas into condensed water, and the condensed water adsorbs the alkaline ammonia molecules (ammonia gas), cement raw material dust (calcium-containing), and the acidic SO 2 and CO 2 and other gases in the flue gas. The alkaline ammonia molecules and cement raw material dust react with the acidic SO 2 and CO 2 in the condensed water to undergo an acid-base neutralization reaction to form non-volatile salts such as ammonium bisulfate, ammonium bicarbonate, calcium sulfate, and calcium carbonate.

[0095] The purification equipment of the present application further includes a condensed water collection device 23, which is arranged at the bottom of the low-temperature condensation module 1. The condensed water collection device 23 is connected to the condensed water discharge port 10. The condensed water generated on the surface of the cooling water pipe bundle 102 flows down the surface of the pipe to the bottom of the purification equipment, and then is collected by the condensed water collection device 23. Finally, the condensed water discharge port 10 discharges the condensed water externally.

[0096] Furthermore, the externally discharged condensed water can be treated by the membrane separation method into reusable or externally discharged purified water (about 90%) and about 10% of high-concentration water containing salts (the salt dust content is less than 3%). The high-concentration water containing salts is pumped and sprayed onto the clinker grate cooler at the kiln head of the cement kiln. On the one hand, it can quickly cool the clinker. On the other hand, substances such as calcium sulfate and calcium carbonate in the water adhere to the surface of the clinker and are taken out as components of the cement. The ammonium salts in the water are quickly heated and decomposed into ammonia and SO 2 and then enter the decomposition furnace of the cement kiln along with the tertiary air. Among them, the ammonia molecules play a denitrification function and are utilized in the decomposition furnace, and SO 2 reacts with CaO to form calcium sulfate and enters the clinker. The whole process has no secondary pollution, and all substances are recycled.

[0097] In the prior art known above, although it also discloses using a heat exchanger to cool the denitrified flue gas, the role of its heat exchanger in the above prior art is completely different from the role of the low-temperature condensation module 1 in the present application. The specific differences are as follows:

[0098] 1. Different inventive concepts

[0099] The above-mentioned prior art mainly removes ammonia by spraying absorbent in a spray tower, and the purpose of setting the heat exchanger is to reduce the load of the spray tower; the present application utilizes the fact that cement kiln flue gas contains water vapor, and the low-temperature condensation module 1 cools down the water vapor in the high-temperature flue gas and condenses it into condensed water, ammonia and SO 2 , CO 2 Acidic gases such as SO2 are easily dissolved in condensed water under the low temperature environment of the low temperature condensation module 1 (physical process). At the same time, alkaline ammonia molecules and acidic SO 2 With CO 2 Neutral acidic and alkaline substances undergo a neutralization reaction to form non-volatile substances such as ammonium bisulfate, ammonium bicarbonate, calcium sulfate and calcium carbonate (chemical process), which are discharged with the condensed water, so that the problem of ammonia escape in the cement kiln is effectively solved; the present application directly undergoes a deamination reaction in the heat exchanger without the need to add any absorbent.

[0100] 2. The role played by the heat exchanger in the prior art is objectively different from that of the low-temperature condensation module 1 of the present application.

[0101] 1) Although the prior art records that the heat exchanger can cool the flue gas to 50 degrees, it does not disclose that deamination is performed in the heat exchanger. From the full text of the prior art, the heat exchanger has no deamination effect. This is because, based on the inventive concept, the denitrified flue gas after cooling by the heat exchanger enters the spray tower, and the spray tower absorbs ammonia by spraying absorbent. For designers, it is not intentional to divide the ammonia absorption into two steps, that is, ammonia absorption in the heat exchanger part and ammonia absorption in the subsequent spray tower, which will only increase the difficulty of ammonia recovery;

[0102] 2) Based on the inventive concept of the prior art, the heat exchanger does not need to play a deamination role, because deamination is still required by spraying absorbent. If the heat exchanger can achieve deamination, there is no need for spray tower treatment.

[0103] 3) It is very important that for traditional heat exchangers, the general goal is to avoid generating condensed water as much as possible during the heat exchange process, because condensed water will corrode the pipes of the heat exchanger over a long period of time, resulting in a reduction in the service life of the heat exchanger. Therefore, it can be concluded that the heat exchanger of the prior art is not intended to generate condensed water.

[0104] 3. The above-mentioned known prior art has many defects

[0105] 1) There is a risk of absorbent escape. The ammonia absorbent used is formic acid. The volatilization and escape of the absorbent also require further treatment, and formic acid is also a flammable substance;

[0106] 2) The amount of wastewater treated after the absorbent absorbs ammonia is large, and the treatment cost is high;

[0107] 3) Since the method of spraying absorbent cannot fully utilize the absorbent, in order to improve the utilization rate of the absorbent, the absorbent has to be recycled. Not only does it require a long precipitation period, but the reflux pipeline used for the period of recycling will also suffer from severe corrosion, making the solution difficult to implement;

[0108] 4) It is difficult to detect whether the absorbent is saturated, and ineffective absorption is likely to occur, causing ammonia escape.

[0109] The purification equipment of the present application is different from the heat exchanger of the prior art, because the application scenario of the purification equipment of the present application is limited to the purification of flue gas containing water vapor, ammonia and acidic pollutants, and the pursuit of more condensed water in the cooling process to achieve physical and chemical purification is completely different from the concept of the existing heat exchanger. In addition, the purification equipment of the present application realizes self-sustaining, one-step deamination, and has the advantages of simple deamination process, small equipment size and low cost.

[0110] In addition, the purification equipment of the present application is not only suitable for deamination, because in the condensed water produced by the low-temperature condensation module 1, the alkaline ammonia gas, cement raw material dust and the acidic SO in the flue gas 2 , CO 2 , NOx and other acidic and alkaline substances undergo neutralization reactions, so the purification equipment in this application can also be used to remove SO 2 , CO removal 2 and deNOx.

[0111] The cooling water tube bundle 102 of the low temperature condensation module 1 of the present application is arranged in a staggered tube bundle array. Specifically, Figure 2B As shown, the cooling water tube bundle 102 includes multiple rows of cooling water tubes 102a arranged along the smoke flow direction, and two adjacent rows of cooling water tubes 102a are staggered in the smoke flow direction and have no gap between the orthographic projection surfaces in the smoke flow direction.

[0112] As a preferred embodiment of the present application, the orthographic projection surfaces of two adjacent rows of cooling water pipes 102a in the multiple rows of cooling water pipes 102a in the direction of the flue gas flow intersect. This arrangement allows the flue gas entering the flue gas channel to zigzag through the gaps of the cooling water pipe bundle 102, thereby increasing the heat exchange contact area between the flue gas and the cooling water pipe bundle 102 as much as possible, and ensuring that the normal flow of the flue gas does not affect the purification of the continuously incoming flue gas.

[0113] As a variation of the arrangement of the cooling water pipe bundle 102, in other embodiments, the boundaries of the front projection planes of two adjacent rows of cooling water pipes 102a in the multi-row cooling water pipes 102a coincide in the flue gas flow direction. That is, the maximum width dimension of a cooling water pipe 102a in the previous row is exactly equal to the gap width between two adjacent cooling water pipes 102a in the next row. This setting method can also avoid the situation where some flue gas directly passes through the gap existing between two adjacent rows of cooling water pipes 102a in the front-back direction without contacting the surface of the cooling water pipes 102a for heat exchange.

[0114] In this application, the cooling water pipe 102a can be in the shape of a circular pipe, an elliptical pipe, a rectangular pipe, a rhombic pipe, etc. However, considering how to minimize the resistance encountered by the flue gas in the cooling water pipe bundle 102, maximize the heat exchange contact area between the flue gas and the cooling water pipe bundle 102, and maximize the heat exchange efficiency between the cooling water pipe 102 and the flue gas, it is necessary to carry out a refined design of the shape of the cooling water pipe 102.

[0115] For this reason, as a preferred embodiment of this application, an arc-rhombus cooling water pipe is proposed, as Figures 7A - 7C shown. The arc-rhombus cooling water pipe includes: a cooling water pipe body 1020, the cross-section of the cooling water pipe body 1020 is in the shape of an arc rhombus, and the two ends of the short diagonal of the cross-section of the cooling water pipe body 1020 are respectively large arc ends 1020b, and the two ends of the long diagonal are respectively small arc ends 1020a;

[0116] The large arc ends 1020b at both ends of the short diagonal and the small arc ends 1020a at both ends of the long diagonal are respectively connected by straight edges 1020c, and the straight edges 1020c are tangent to the arc lines of the large arc ends 1020b.

[0117] As Figures 7A - 7C shown, the radius of curvature of the large arc end 1020b is much larger than that of the small arc end 1020a, that is, the curvature of the large arc end 1020b is much smaller than that of the small arc end 1020a. Due to the large curvature of the small arc end 1020a, an acute angle is formed together with the two straight edges 1020c.

[0118] The cooling water pipe body 1020 is in a long strip structure, and its interior is a hollow structure for the flow of cooling water. When the cooling water pipe 102a is applied to a low-temperature condensation device, the small arc ends 1020a of the cooling water pipe body 1020 are horizontally arranged along the flue gas inlet 4 to the flue gas outlet 5 direction, that is, horizontally arranged along the left-right direction of the low-temperature condensation device, and the midpoint connection line of the two large arc ends 1020b is perpendicular to the connection line of the two small arc ends 1020a, that is, the two large arc ends 1020b are horizontally arranged along the front-back direction of the low-temperature condensation device.

[0119] In the embodiments of the present application, the cooling water pipe body 1020 with a cross-section in the shape of an arc rhombus is defined as an arc rhombus pipe. Compared with cooling water pipes with circular, elliptical, rhombus-shaped cross-sections, etc., it can achieve a larger heat exchange contact area between the flue gas and the cooling water pipe and a smaller flue gas resistance. The specific analysis is as follows:

[0120] Comparison with a circular pipe:

[0121] The length of the short diagonal of the arc rhombus pipe is the same as the diameter of the original circular cooling water pipe, while the length of the long diagonal is greater than the diameter of the original circular cooling water pipe. This makes the surface area of the improved arc rhombus pipe at both ends larger than that of the original circular cooling water pipe, thereby increasing the contact area between the cooling water pipe and the cement kiln flue gas, that is, increasing the heat exchange area.

[0122] In addition, since the radius of curvature of the small arc end 1020a of the cooling water pipe body 1020 is much smaller than that of the large arc end, that is, the two ends of the cooling water pipe body 1020 are acute angles with a smaller included angle. Compared with the shape of the two ends of the circular cooling water pipe, the arc rhombus-shaped cooling water pipe body 1020 has a smaller wind resistance at both ends. Therefore, the arc rhombus achieves resistance reduction compared with the circle.

[0123] Comparison with an elliptical pipe:

[0124] The arc rhombus pipe has two differences compared with the elliptical pipe. The first difference is that in the cooling water pipe body 1020 of the present application, the large arc end 1020b and the small arc end 1020a are connected by a straight edge 1020c, while the elliptical pipe is connected by an arc edge. When two cooling water pipes 102a are arranged in a staggered manner, the flow space formed between the two elliptical pipes is a structure with large ends and a small middle, while the flow space formed between the two arc rhombus pipes is more flat in size. Therefore, it is more conducive to the flow of the tail gas and can avoid the influence on the tail gas flow caused by the change in the size of the flow space.

[0125] The second difference is that in order to form an arc rhombus structure in the present application, when the size of the large arc end 1020b with a large radius of curvature is unified, the radius of curvature of the other small arc end 1020a of the elliptical pipe is necessarily larger than that of the arc rhombus pipe. Therefore, the arc rhombus pipe has a smaller wind resistance at both ends compared with the elliptical pipe, and the technical effect of resistance reduction can also be achieved.

[0126] Comparison with a conventional rhombus pipe:

[0127] Compared with the diamond tube, the cross-sectional shape of the arc diamond tube is equivalent to replacing the upper and lower pointed ends of the diamond tube cross-section with large arc ends 1020b with a small curvature, and replacing the left and right pointed corners with small arc ends with a large curvature. For the large arc ends 1020b at the upper and lower ends of the arc diamond tube, compared with the obtuse ends at the upper and lower ends of the diamond tube, the use of arc transition can make the flow of flue gas more stable. In addition, replacing the left and right pointed corners with small arc ends with a large curvature can prevent the flue gas from separating at the rear end.

[0128] In addition, the diamond tube with pointed ends at the left and right ends will cause excessive deformation at its left and right ends and is prone to fracture. And due to structural limitations, the thickness at the two ends of the diamond tube is generally greater than that of other parts, resulting in an increased heat conduction path of the cooling water at the two ends of the diamond tube, which will reduce the heat exchange efficiency. However, setting it into a small arc structure can make the thickness at the two ends of the arc diamond tube close to that of other parts, and will not increase the heat conduction path of the cooling water at the two ends, and thus will not affect the heat exchange efficiency.

[0129] This embodiment achieves the purpose of increasing the heat exchange area at both ends of the cooling water pipe body 1020, and using the large arc ends 1020b and small arc ends 1020a to reduce the resistance suffered by the cement kiln tail gas during flow, so that the cement kiln tail gas flows smoothly. Thus, the technical effect of increasing the contact area between the cement kiln tail gas and the cooling water pipe body 1020, making the cement kiln tail gas flow smoothly, and improving the cooling efficiency of the cement kiln tail gas is achieved. Furthermore, the problem in the related technology that the cooling water pipe has a small heat exchange area and a large resistance to the flow of the cement kiln tail gas, and cannot well improve the cooling efficiency of the cement kiln tail gas is solved.

[0130] The connecting line of the midpoints of the large arc ends 1020b at both ends of the short diagonal is perpendicular to the connecting line of the small arc ends 1020a at both ends of the long diagonal.

[0131] Both the large arc ends 1020b and the small arc ends 1020a include inner rounded corners and outer rounded corners. To avoid the problem of thickness change of the cooling water pipe body 1020 at the upper and lower ends and the left and right ends due to the setting of the rounded corners, in this embodiment, the inner rounded corner and the outer rounded corner of the large arc end 1020b are concentrically arranged, and the inner rounded corner and the outer rounded corner of the small arc end 1020a are concentrically arranged.

[0132] Since the size design of the cross-section of the cooling water pipe body 1020 still has a great influence on the heat exchange efficiency, in order to make reasonable use of space and improve the heat exchange efficiency, the applicable ranges of the sizes of the cross-section of the cooling water pipe body 1020 in this embodiment are as follows:

[0133] A = 20~100mm;

[0134] B = A~2A;

[0135] R 1 = 1 / 2 × A;

[0136] R 2 = R 1 - t;

[0137] r 1 = 6 ~ 1 / 2 × R 1 ;

[0138] r 2 = r 1 - t;

[0139] Wherein, A is the length of the short diagonal of the cooling water pipe body 1020; B is the length of the long diagonal of the cooling water pipe body 1020; R 1 is the outer diameter dimension of the large arc end 1020b; R 2 is the inner diameter dimension of the small arc end 1020a; t is the wall thickness of the cooling water pipe body 1020; r 1 is the outer diameter dimension of the small arc end 1020a; r 2 is the inner diameter dimension of the large arc end 1020b.

[0140] Since the cooling water pipe 102a in the present application is an arc-shaped rhombus pipe, compared with a circular pipe, it is more difficult to install, it is difficult to ensure the sealing performance of its connection, and it is not convenient to connect with the water inlet and return water pipelines. Therefore, the cooling water pipe 102a provided in this embodiment further includes an upper joint 22 and a lower joint 21 respectively arranged at both ends of the cooling water pipe body 1020; wherein, the upper joint 22 and the lower joint 21 have the same structure, and both include a plug 211 and a joint 213. The plug 211 is hermetically fixed at both ends of the cooling water pipe body 1020, and the first end of the joint 213 is hermetically fixed on the plug 211 and communicated with the inside of the cooling water pipe body 1020, and the second end extends out of the plug 211.

[0141] Specifically, it should be noted that the two ends of the cooling water pipe body 1020 are blocked by the plug 211. The cross-section of the plug 211 can be equal to or larger than the cross-section of the cooling water pipe body 1020, and the two ends of the cooling water pipe body 1020 are sealed through the plug 211. The plug 211 can provide an installation position for the joint 213, so that the joint 213 can be installed on the plug 211, and then the joint 213 is connected to the water inlet and return water pipelines. The joint 213 can be set to a structure convenient for connection, such as circular. Through the arrangement of the plug 211 and the joint 213, the technical effect of improving the sealing performance of the cooling water pipe body 1020 and being convenient for connecting with the water inlet and return water pipelines is achieved, and further solves the problem that it is difficult to ensure the sealing performance of the connection during the installation of non-circular cooling water pipes in the related art, and it is not convenient to connect with the water inlet and return water pipelines, resulting in a more troublesome installation.

[0142] Furthermore, the cross-section of the plug 211 is set to be the same arc-rhombus shape as that of the cooling water pipe body 1020. A joint installation hole is axially formed on the plug 211, and the joint installation hole communicates with the inside of the cooling water pipe; the first end of the joint 213 is hermetically fixed in the joint installation hole.

[0143] To improve the sealing performance between the joint 213 and the joint installation hole, the first end of the joint 213 is threadedly connected to the joint installation hole, and thread sealant can be injected to enhance the sealing performance. To facilitate the connection between the joint 213 and external equipment, the end of the joint 213 away from the plug 211 is also provided with internal or external threads.

[0144] An annular groove is provided in the joint installation hole, and a sealing ring 212 is embedded in the annular groove. The joint 213 is threadedly connected to the joint installation hole and presses the sealing ring 212 against the annular groove, thereby improving the sealing performance between the joint 213 and the joint installation hole.

[0145] In this application, as Figure 8 shown, the adjacent two rows of the cooling water pipe bodies 1020 and the three adjacent cooling water pipe bodies 1020 form a cooling water pipe unit arranged in a triangular pattern. The arrangement dimension range of the cooling water pipe unit is:

[0146] C = 1.8A~2A;

[0147] D = 0.8B~1.5B;

[0148] wherein, A is the maximum width dimension of the pipe cross-section; B is the maximum length dimension of the pipe cross-section; C is the center distance dimension of the pipe cross-sections of two adjacent cooling water pipe bodies 1020 in the same row; D is the center distance dimension of the pipe cross-sections of the cooling water pipe bodies 1020 in adjacent rows.

[0149] When the cooling water pipe 102a is an arc-rhombus pipe, A is the maximum width of the short diagonal of the arc-rhombus pipe; B is the maximum length of the long diagonal of the arc-rhombus pipe; C is the center distance between two adjacent arc-rhombus pipes in the same row; D is the horizontal center distance between two adjacent arc-rhombus pipes in adjacent rows.

[0150] Figure 13 shows a simplified diagram of the convective heat transfer of the low-temperature condensation module of this application. In the figure, s 1 is the row pitch of the staggered tube bundle, and s 2 is the column pitch of the staggered tube bundle.

[0151] The heat transfer on the flue gas side of the low-temperature condensation module of this application is that the fluid flows across the staggered tube bundle, and the relationship between its surface average heat transfer coefficient h and the dimensionless heat transfer coefficient Nu is:

[0152] ;

[0153] wherein l is the characteristic length, is the thermal conductivity of the fluid.

[0154] For the studied flue gas heat exchange condition, the Reynolds number range of its flow is about Re = 10 3 ~2×10 5 , and Nu can be expressed as:

[0155] ;

[0156] where s 1 is the row pitch of the staggered tube bundle, s 2 is the column pitch of the staggered tube bundle. Re f is the Reynolds number of the flue gas flow, Pr f is the Prandtl number of the flue gas, Pr w is the Prandtl number of the flue gas with the wall temperature as the characteristic temperature.

[0157] In engineering calculations, if the logarithmic mean temperature difference of convective heat transfer is given as , then according to the heat transfer equation, the overall heat transfer amount is:

[0158] ;

[0159] wherein, k is the comprehensive heat transfer coefficient, and A is the heat transfer area.

[0160] As can be seen from the above analysis, the heat transfer area of the arc-shaped diamond tube is larger than that of the circular tube. Therefore, using the arc-shaped diamond tube as the cooling water pipe 102a in this application can increase the overall heat transfer amount of the equipment.

[0161] Using the arc-shaped diamond tube will also affect the flow resistance of the flue gas. The circular tube and the preferred arc-shaped diamond tube of this application will be compared and analyzed below.

[0162] The flow resistance relationship formula for the circular tube in staggered arrangement is:

[0163] When the gas flows around the tube bundle, the flow resistance is a function of the fluid velocity, tube bundle arrangement, fluid physical properties, and the number of rows. Its correlation formula is

[0164] ;

[0165] wherein, is the correction coefficient of the staggered tube bundle, and is the relational formula of the pipeline parameters s 1 , s 2 , is the number of pipeline rows, f is the resistance coefficient, f is a value that depends on the change of the flow Reynolds number Re.

[0166] The flow resistance relationship formula for the staggered arrangement of arc-rhombus tubes is as follows:

[0167] The long side of the arc-rhombus tube is l 1 , and the short side is l 2 . With a design correction coefficient ε, the flow resistance relationship formula for the staggered arrangement of arc-rhombus tubes is:

[0168] ;

[0169] Among them, is the correction coefficient related to the side length of the arc-rhombus tube compared to the staggered tube bundle of circular tubes, which is greater than 1. The meanings of the other parameters are the same as those in the above formula.

[0170] The sides of the arc-rhombus are similar to the streamline properties of an airfoil. Compared with a circular tube, the flow boundary layer separation area at the tail is reduced, and the adverse pressure gradient is decreased, so the overall resistance will decrease.

[0171] As Figures 3A - 3B shown, the box body structure of the purification device in this application preferably adopts a rectangular box body structure. Specifically: The box body 101 includes an upper box plate 1011, a lower box plate 1012, a front box plate 1013, and a rear box plate 1014. The upper box plate 1011, the front box plate 1013, the lower box plate 1012, and the rear box plate 1014 are sequentially and hermetically connected; The left and right sides of the box body 101 are open to form a flue gas inlet 4 and a flue gas outlet 5 for the flow of flue gas, and a flue gas passage from the flue gas inlet 4 to the flue gas outlet 5; The flue gas passage is used to accommodate a cooling water tube bundle 102 arranged vertically and in an array; A plurality of water pipe installation holes 102b for hermetically assembling the ends of the cooling water pipes 102a are provided on the upper box plate 1011 and the lower box plate 1012; Spaces for assembling end joint components for connecting the upper and lower ends of the cooling water tube bundle 102 are left above the upper box plate 1011 and below the lower box plate 1012. However, this application does not limit that the box body structure must be a rectangular structure. Those skilled in the art should understand that in some special application scenarios, the box body structure can be appropriately deformed, such as an arc-shaped box body structure with a certain curvature, such as a trapezoidal box body structure with different sizes of flue gas inlets and flue gas outlets, etc.

[0172] In this application, the upper and lower ends of the cooling water tube bundle 102 are installed on the upper box plate 1011 and the lower box plate 1012. Considering that the purification device needs to operate for a long time, when the low-temperature condensation module 1 works, the cooling water pipes 102a are impacted by flue gas and will generate frequent vibrations, which are likely to cause the problem of flue gas leakage at the connection between the upper and lower ends of the cooling water pipes 102a and the upper and lower box plates. To solve this problem, asFigures 9A to 10B As shown, the present application proposes a sealed installation structure for a cooling water pipe and a box plate. The sealed installation structure includes an installation base 20 and a cooling water pipe body 1020; among them,

[0173] A water pipe installation hole 102b is opened on the installation base 20, and an annular groove 17 is opened along the circumferential direction of the hole wall of the water pipe installation hole 102b; in this embodiment, the installation base 20 is the upper box plate 1011 and the lower box plate 1012 of the box body 101.

[0174] The end of the cooling water pipe body 1020 is arranged in the water pipe installation hole 102b, and a part of the cooling water pipe body 1020 corresponding to the annular groove 17 is provided with an annular protrusion 18, and the annular protrusion 18 is hermetically embedded in the annular groove 17 so that the end of the cooling water pipe body 1020 and the water pipe installation hole 102b form a curved surface seal.

[0175] In this embodiment, the cooling water pipe body 1020 has a long strip structure, and its interior is hollow and can be used for the flow of cooling water. The installation base 20 is the upper box plate 1011 or the lower box plate 1012 of the present application. In the prior art, in order to improve the sealing performance between the cooling water pipe body 1020 and the installation base 20, generally, a sealing ring is fixed on the installation base 20, and the cooling water pipe body 1020 is fixed in the sealing ring, and the sealing performance at the connection between the cooling water pipe body 1020 and the installation base 20 is improved through the sealing ring.

[0176] However, since the outer side of the cooling water pipe body 1020 is still a straight curved surface structure, and the corresponding position of the sealing ring and the installation base 20 is also a straight curved surface structure, when the cooling water pipe body 1020 is installed on the sealing ring and the installation base 20, the straight curved surface structure is still difficult to maintain the sealing performance for a long time, resulting in an unsatisfactory sealing effect.

[0177] Therefore, to solve this problem, as Figure 9B and 10B shown, in this embodiment, a water pipe installation hole 102b is opened on the installation base 20, and an annular groove 17 is opened in the water pipe installation hole 102b. The end of the cooling water pipe body 1020 is sleeved in the water pipe installation hole 102b. To make the cooling water pipe body 1020 and the annular groove 17 fit, an annular protrusion 18 can be provided on the outer side of the cooling water pipe body 1020, and the annular protrusion 18 is hermetically embedded in the annular groove 17, so that a curved surface seal is formed between the annular protrusion 18 and the annular groove 17.

[0178] Due to the provision of the annular groove 17, the inner surface of the water pipe installation hole 102b on the installation base 20 is changed from a straight curved surface structure to a zigzag curved surface structure, and the outer surface of the end of the cooling water pipe body 1020 is changed from a straight curved surface structure to a zigzag curved surface structure. It can be understood that when the cooling water pipe body 1020 is installed in the water pipe installation hole 102b, the connection part between the cooling water pipe body 1020 and the water pipe installation hole 102b is also changed from a straight curved surface structure to a zigzag curved surface structure, thereby improving the sealing performance of the connection part between the cooling water pipe body 1020 and the water pipe installation hole 102b. An interference fit can be adopted between the annular protrusion 18 and the annular groove 17 to further improve the sealing performance.

[0179] This embodiment achieves the technical effect of improving the sealing performance between the cooling water pipe body 1020 and the installation base 20 and preventing the tail gas from leaking from the connection part between the two, thereby solving the problem that in the related art, only sealant 16 or sealing rings are generally used for sealing between the cooling water pipe and the installation base 20, and the sealing performance is still difficult to meet the use requirements.

[0180] As Figure 9B and 10B shown, the annular groove 17 in the water pipe installation hole 102b can be formed by grooving with a special tooling. The width of the cross-section of the annular groove 17 can gradually decrease from the inside to the outside, so as to form a small arc end structure with a smaller diameter at its outermost end. Compared with a rectangular groove or other shaped groove structures, the structure of this annular groove 17 has better sealing performance when the annular protrusion 18 cooperates with it. The annular protrusion 18 on the cooling water pipe body 1020 can be realized by expanding the pipe. Specifically, the cooling water pipe body 1020 can be sleeved in the water pipe installation hole where the annular groove 17 has been formed, and through a special pipe expanding tooling, an outward expanding pressure is applied to the part of the cooling water pipe body 1020 corresponding to the annular groove 17, so that the cooling water pipe body 1020 deforms at the corresponding part to form the first annular protrusion 18 and is pressed and fixed in the annular groove 17.

[0181] To further improve the sealing performance of the connection part between the cooling water pipe body 1020 and the installation base 20, sealant 16 is provided in the annular groove 17. The sealant 16 can be applied in the annular groove 17 before installing the cooling water pipe body 1020. After the cooling water pipe body 1020 is expanded to form the annular protrusion 18 and is embedded in the annular groove 17, the sealing performance is improved under the action of the sealant 16.

[0182] To improve the uniformity of the opening depth of the annular groove 17, the annular groove 17 is coaxially arranged with the water pipe installation hole.

[0183] As Figure 9B and 10BAs shown, a rubber gasket 15 is also provided in the annular groove 17, and the annular protrusion 18 presses the rubber gasket 15 tightly in the annular groove 17. The shape of the rubber gasket 15 matches that of the annular groove 17. The rubber gasket 15 can be first embedded in the annular groove 17, then the sealant 16 is injected into the annular groove 17, and finally the cooling water pipe body 1020 is sleeved in the water pipe installation hole 102b.

[0184] The annular groove 17 includes a plurality of grooves arranged at intervals circumferentially along the inner wall of the water pipe installation hole 102b, and the extension depths of the plurality of grooves on the inner wall are the same or different. The plurality of grooves can increase the contact points between the cooling water pipe body 1020 and the inner wall of the water pipe installation hole 102b. When the extension depths of the plurality of grooves are different, the sealing performance between different contact points can be different, and the depth of the grooves can be adjusted according to the actual exhaust gas flow conditions to improve the scope of use.

[0185] To further improve the sealing performance at the connection between the cooling water pipe body 1020 and the installation base 20, a plurality of annular grooves 17 are arranged along the axial direction of the water pipe installation hole 102b, so as to form a multi-stage seal, and the sealing method of each stage is the same.

[0186] To further improve the sealing performance, as Figure 10B shown, in this embodiment, the annular groove 17 is provided with two, including a first annular groove 171 and a second annular groove 172. The groove opening direction of the first annular groove 171 and the groove opening direction of the second annular groove 172 are inclined in opposite directions along the axial direction of the water pipe installation hole; correspondingly, the annular protrusion 18 includes a first annular protrusion 18 and a second annular protrusion 18, and the protrusion directions of the first annular protrusion 18 and the second annular protrusion 18 are inclined in opposite directions along the axial direction of the water pipe installation hole.

[0187] Specifically, it should be noted that the first annular groove 171 and the second annular groove 172 are arranged in sequence from the inside to the outside. The groove opening direction of the first annular groove 171 can be inclined towards the inside of the installation base 20, while the groove opening direction of the second annular groove 172 can be inclined towards the outside of the installation base 20, so that the connection between the cooling water pipe body 1020 and the water pipe installation hole 102b is sealed in different directions.

[0188] Moreover, in this embodiment, the depth of the second annular groove 172 is greater than the depth of the first annular groove 171. Through this setting method, the second annular groove 172 forms a secondary seal with better sealing performance, further improving the overall sealing performance at the connection.

[0189] After the annular groove 17 cooperates with the annular groove 17 located in the water pipe installation hole 102b, the sealing performance of the part inside the water pipe installation hole 102b is effectively improved. However, the parts at both ends of the water pipe installation hole 102b are still straight curved surface structures, and their sealing performance still needs to be improved. Therefore, as Figure 10B shown, in this embodiment, two annular clamping protrusions 19 are further provided on the cooling water pipe body 1020. The two annular clamping protrusions 19 are located on the inner side and the outer side of the installation base 20, that is, at both ends of the water pipe installation hole 102b. The opposite surfaces of the two annular clamping protrusions 19 are respectively abutted against the inner side surface and the outer side surface of the installation base 20. By using the two annular clamping protrusions 19 to respectively form the first seal and the last seal at the connection between the cooling water pipe body 1020 and the installation base 20, the sealing performance can be further enhanced, and at the same time, the connection strength between the cooling water pipe body 1020 and the installation base 20 can also be improved.

[0190] As a preferred embodiment of the present application, the water pipe installation hole 102b is an arc rhombus hole that is consistent with the cross-sectional contour and size of the end of the arc rhombus pipe. The annular groove 17 includes a plurality of grooves, which are arranged in sequence on the four straight edges 1020c and the two large arc ends 1020b of the arc rhombus hole. Correspondingly, the annular protrusion 18 includes a plurality of protrusions, which are arranged on the four straight edges 1020c and the two large arc ends 1020b of the end of the arc rhombus pipe. The fitting and sealing cooperation between the plurality of grooves and the plurality of protrusions, combined with the fitting depths of different grooves and protrusions, and then combined with the special shape of the arc rhombus, enables the sealing performance at the connection between the cooling water pipe 102a and the installation base 20 (the upper box plate 1011 and the lower box plate 1012) to meet the requirements that the purification equipment can work for a long time without smoke leakage.

[0191] In the present application, the structural form of the end joint assembly will affect the flow form of the cooling water from the cooling water inlet 103a to the cooling water return port 104a. Five embodiments of the low-temperature condensation module 1 with different end joint assemblies are proposed in the present application.

[0192] Figures 2C - 2E An embodiment of the low-temperature condensation module with a circular pipe elbow as the end joint is shown. As can be seen from the figure, the end joint assembly is a circular pipe elbow assembly that sequentially connects the ends of two adjacent cooling water pipes 102a. Along the direction from the flue gas inlet 4 to the flue gas outlet 5, the ends of two adjacent rows of cooling water pipes 102 are connected by a circular pipe elbow 105 located outside the box plate.

[0193] In this embodiment, the cooling water circulation pipeline is arranged above the box body 101 of the low-temperature condensation module 1. In other embodiments, it can also be arranged below, and the specific position is set according to actual needs. The cooling water circulation pipeline is set in two groups. The cooling water pipe bundle 102 is divided into two front and rear cooling water pipe areas 24 in the box body 101 along the direction from the flue gas inlet 4 to the outlet. The cooling water inlet pipeline 103 and the cooling water return pipeline 104 of the two groups of cooling water circulation pipelines are respectively communicated with the inlet cooling water pipeline and the outlet cooling water pipeline of the front and rear two cooling water pipe areas 24. Since the temperature of the flue gas near the flue gas inlet 4 is high, a large cooling temperature drop is required for the cooling water pipe 102a near the flue gas inlet 4. And on the basis of the temperature reduction of the flue gas on the side of the flue gas outlet 5 by the front-side cooling water pipe 102a, a small cooling temperature drop is required for the cooling water pipe 102a near the flue gas outlet 5. Therefore, in this embodiment, the cooling water flow rate in the cooling water pipe area 24 near the outlet side can be reduced, so as to save the cooling water consumption. Specifically, the way to reduce the cooling water flow rate in the cooling water pipe area 24 near the outlet side can be to reduce the pipe diameter (i.e., the cross-sectional area size) of the cooling water pipe 102a or reduce the inlet flow rate of the cooling water inlet pipeline 103. In other embodiments, the cooling water flow rate in the cooling water pipe area 24 on the outlet side may not be reduced, that is, the cooling water consumption in the cooling water pipe area 24 on the inlet side is the same as the flow rate in the cooling water pipe area 24 on the outlet side. In addition, it should be noted that the present application does not limit the number of the cooling water pipe areas 24. In other embodiments, according to actual needs, it can also be set to three, four, five, etc.

[0194] In the above embodiment, since the number of the cooling water pipes 102 is large, the same number of round pipe elbows 105 are required. However, a large number of round pipe elbows 105 will cause kinetic energy resistance loss of the cooling water at the turning points, reducing the heat exchange efficiency of the low-temperature condensation module 1. At the same time, in order to reduce the overall volume of the low-temperature condensation module 1, the setting distance of the cooling water pipes 102 is small. To connect the ends of two cooling water pipes 102 with the round pipe elbow 105, the radian of the round pipe elbow 105 is small, and the processing difficulty is large.

[0195] To solve the problems of large kinetic energy resistance loss of the cooling water at the round pipe elbow 105 and large processing difficulty of the round pipe elbow 105, as Figures 3A - 6D shown in the embodiment of using a water tank to replace the round pipe elbow 105 as the end joint assembly.

[0196] Specifically, the end joint assembly includes an upper end joint assembly 25 and a lower end joint assembly 26. The upper end joint assembly 25 and the lower end joint assembly 25 are alternately arranged in sequence above and below the cooling water pipe bundle 102 along the flue gas flow direction, and each end joint penetrates through the ends of multiple rows of cooling water pipes 102a to form a parallel pipeline in the cooling water pipe bundle 102 for at least two rows of parallel water flows to flow in the same direction. Specifically, the upper end joint assembly 25 is an upper water tank 11, and the lower end joint assembly 26 is a lower water tank 12. The upper water tank 11 includes a plurality of upper water tank sub-parts 111 serving as the end joints, which are arranged in sequence along the flue gas flow direction above the cooling water pipe bundle 102. The lower water tank 12 includes a plurality of lower water tank sub-parts 121 serving as the end joints, which are arranged in sequence along the flue gas flow direction below the cooling water pipe bundle 102. The multiple rows of cooling water pipes 102a penetrated by each water tank sub-part include an inlet water pipeline and an outlet water pipeline arranged side by side along the flue gas flow direction, and the number of rows of the inlet water pipeline and the outlet water pipeline is the same.

[0197] Figures 3A - 3D An embodiment showing the circulation of cooling water along the grouped water pipes is shown. In this embodiment, water tanks are arranged on the outer sides of the upper and lower box plates of the box body 101 to replace the circular pipe elbows 105 in Embodiment 1 to achieve the connection of the ends of the cooling water pipes 102. An upper water tank 11 is arranged above the upper box plate 1011, and a lower water tank 12 is arranged below the lower box plate 1012. A number of partition plates are arranged in the upper water tank 11 to divide the upper water tank 11 into the 1st to the Nth upper water tank sub-parts 111, and a number of partition plates are arranged in the lower water tank 12 to divide the lower water tank 12 into the 1st to the Nth lower water tank sub-parts 121. Each upper water tank sub-part 111 or lower water tank sub-part 121 correspondingly connects the ends of at least two rows of cooling water pipes 102. The cooling water inlet pipeline 103 is connected to the 1st lower water tank sub-part 121 close to the flue gas inlet 4, and the cooling water return pipeline 104 is connected to the Nth upper water tank sub-part 111 farthest from the flue gas inlet 4. The 2nd to the Nth lower water tank sub-parts 121 of the lower water tank 121 are respectively arranged in an interleaved manner with the 1st to the N - 1th upper water tank sub-parts 111 of the upper water tank 111. Specifically, as Figure 3AAs shown in the figure, the cooling water enters the first lower water tank section 121 of the lower water tank from the cooling water inlet. The first lower water tank section 121 corresponds to 4 rows of cooling water pipes 102a. Driven by the pressure of the water pump 9, the cooling water flows upward along these 4 rows of cooling water pipes 102a and flows out from the first 4 rows of cooling water pipes 102a of the first upper water tank section 111. As can be seen from the figure, the first upper water tank section 111 corresponds to and is connected to 8 rows of cooling water pipes 102a. The cooling water flowing in from the first 4 rows turns in the first upper water tank section 111 and then flows downward into the last 4 rows of cooling water pipes 102a. The second lower water tank section 121 corresponds to and is connected to 8 rows of cooling water pipes 102a. The cooling water in the 4 rows of cooling water pipes 102a flowing down from the first upper water tank section 111 turns in the second lower water tank section 121 and then flows upward and out from the last 4 rows of cooling water pipes 102a. The second to N-1 upper water tank sections 111 and the third to N lower water tank sections 121 are arranged in sequence according to the above rules. The cooling water circulates in sequence in the lower water tank section 121, the cooling water pipes 102a, and the upper water tank section 111, and finally flows out from the cooling water return port on the Nth upper water tank section 11 of the upper water tank 11.

[0198] In this embodiment, the water tank section replaces the round pipe elbow in the above embodiment, enabling the cooling water routing to change from 1-way turning in the above embodiment to multi-way turning, reducing the number of turns, also reducing the resistance loss of the cooling water turning, and improving the heat exchange efficiency of the cooling water pipe bundle; secondly, the water tank also reduces the processing difficulty and processing cost compared with the round pipe elbow.

[0199] For the flow resistance, since it flows inside the pipe, its flow resistance consists of the frictional resistance along the straight pipe section and the local resistances such as those flowing through elbows, joints, and sudden changes.

[0200] The frictional resistance is expressed as: ,

[0201] where is the frictional resistance coefficient, l is the pipe length, d is the inner diameter of the pipe, is the flow velocity inside the pipe, g is the acceleration due to gravity;

[0202] The local resistance is expressed as: ,

[0203] where is the local resistance coefficient, and N is the number of local resistance components.

[0204] From the above two formulas, the longer the pipe length l , the greater it is, and the greater N is, The greater it is. When changing from the elbow form to the integral water tank, the distance of the water flow from one side to the other side is greatly reduced, and the flow resistance consists only of a small section of frictional resistance and two local resistances. Since the tube bundle array changes from a series arrangement to a parallel arrangement, at this time, the flow resistance of each channel is the same and is greatly reduced.

[0205] It should be noted that the water tank sections in this application can also be independently arranged, that is, the water tank sections are independently formed, and the water tank sections can be fixed to each other through a fixing structure. In addition, the shape of the water tank sections is not limited to the rectangular shape in the embodiments of this application. In other embodiments, in order to further reduce the resistance loss of the cooling water turning, the outer right angles of the rectangular water tank sections can also be machined into rounded corners.

[0206] Considering that the flue gas temperature is high near the flue gas inlet 4 and the cooling water consumption is large, while the flue gas temperature is low far from the flue gas inlet 4 and the cooling water consumption is small. In order to further reduce the cooling water consumption, as the best embodiment of the low-temperature condensation module 1 of this application, Figures 4A - 4C An embodiment in which the cooling water in each straight-through area circulates along the grouped water pipes and the cooling water volume is adjustable is shown. On the basis of the above embodiment in which the cooling water circulates along the grouped water pipes, the cooling water pipes 102 are divided into the 1st to the Nth areas, and a set of cooling water inlets 103a and cooling water outlets 104a are correspondingly arranged for each area of the cooling water pipes 102. Several cooling water pipe areas are isolated from each other and the cooling water circulates independently. This application achieves the purpose of saving the overall water consumption of the low-temperature condensation module 1 by reducing the water inflow of the cooling water pipe area far from the flue gas inlet 4 side. Specifically, in this embodiment, the cooling water pipes 102 are divided into three areas, and the cooling water consumption of the 1st area to the 3rd area is set to decrease in turn. The number of areas for dividing the cooling water pipes 102 in this application is not limited. In other embodiments, according to actual needs, the cooling water pipes 102 can be set to two areas, four areas, five areas, etc. Correspondingly, the cooling water inlets 103a and the cooling water outlets 104a are also set to two groups, four groups, five groups, etc.

[0207] Furthermore, in the embodiments of this application, the method of sequentially reducing the cooling water consumption on the side far from the flue gas inlet 4 is as follows: By setting a flow regulating valve 1031 at the cooling water inlet 103a of the first lower water tank section 121 in each cooling water pipe area, the cooling water consumption of each cooling water pipe area can be adjusted by adjusting the inlet area of the flow regulating valve 1031. Specifically, a water dividing pipe 1033 communicating with the first lower water tank section 121 is arranged on the first lower water tank section 121 in each cooling water pipe area, and the flow regulating valve 1031 is arranged on the water dividing pipe 1033.

[0208] Furthermore, a main cooling water inlet pipe 1032 is provided below the lower water tank 12 in each cooling water pipe area and is respectively connected to each branch water pipe 1033. Cooling water enters from the main cooling water inlet pipe 1032. The main cooling water inlet pipe 1032 distributes the cooling water into each branch water pipe 1033 according to the opening sizes of the respective flow regulating valves 1031. In the embodiment of the present application, in order to save the overall water consumption of the cooling water, the openings of the flow regulating valves 1031 far from the flue gas inlet 4 are gradually reduced. In this way, the amount of cooling water distributed by the main cooling water inlet pipe to the branch water pipes 1033 far from the flue gas inlet 4 is gradually reduced, reducing the overall water consumption of the cooling water on the basis of meeting the condensation efficiency of the low-temperature condensation module 1.

[0209] As an alternative embodiment of the low-temperature condensation module 1 of the present application, the upper end joint assembly 25 is an upper water tank that penetrates the upper ends of all the cooling water pipes, and the lower end joint assembly 26 is a lower water tank. The lower water tank includes a plurality of lower water tank sub-parts arranged along the flue gas flow direction. Each lower water tank sub-part penetrates multiple rows of the cooling water pipes; the upper water tank is connected to a cooling water return port, and each lower water tank sub-part is connected to a cooling water inlet. It further includes a main cooling water inlet pipe, and the main cooling water inlet pipe is connected to each cooling water inlet through a flow regulating valve. Specifically, as Figures 5A - 5C shown in the direct-through type adjustable cooling water embodiment for each area, a plurality of partition plates are provided in the lower water tank 12 to divide the lower water tank 12 into a plurality of lower water tank sub-parts 121. The number of cooling water pipes 102a corresponding to each group of lower water tank sub-parts 121 can be the same or different, and is specifically set according to actual needs. There are no partition plates in the upper water tank 11, and the upper water tank is a return water tank that covers and connects the 1st to the Nth rows of cooling water pipes 102.

[0210] The cooling water enters from the main cooling water inlet pipe 1032 and is distributed to the corresponding lower water tank sub-parts 121 through the flow regulating valves 1031 of each branch water pipe 1033. In this embodiment, each lower water tank sub-part 121 is an inlet water tank. The cooling water flows from each sub-part upward along the cooling water pipe 102a into the upper water tank 11, and finally flows out from the cooling water return port 104a provided at the Nth row of cooling water pipes 102a.

[0211] Furthermore, considering that the flue gas temperature is high and the cooling water consumption is large near the flue gas inlet 4, and the flue gas temperature is low and the cooling water consumption is small far from the flue gas inlet 4, in order to further reduce the cooling water consumption of the low-temperature condensation module 1 in the embodiment of the present application, the cooling water amount of the sub-parts far from the flue gas inlet 4 side is set to be less than that of the sub-parts near the flue gas inlet 4 side. Specifically, along the direction from the flue gas inlet 4 to the outlet, the openings of the flow regulating valves 1031 of the branch water pipes 1033 of each sub-part are gradually reduced.

[0212] As a replaceable embodiment of the low-temperature condensation module 1 of the present application, the upper-end joint assembly 25 is an upper water tank 11 that penetrates through the upper ends of all the cooling water pipes 102a, and the lower-end joint assembly 26 is a lower water tank 12 that penetrates through the lower ends of all the cooling water pipes 102a. One of the upper water tank 11 and the lower water tank 12 is connected to the cooling water inlet 103a, and the other is connected to the cooling water return port 104a. Specifically, as shown in Figures 6A - 6D the embodiment where the cooling water in each straight-through zone circulates along the grouped water pipes and the cooling water volume is adjustable, there is no partition in the upper water tank 11, and the upper water tank 11 is a return water tank connected to the cooling water return port 104a; there is no partition in the lower water tank 12, and the lower water tank 12 is a water inlet tank connected to the cooling water inlet 103a. Both the upper water tank 11 and the lower water tank 12 cover and are connected to the 1st to Nth rows of cooling water pipes 102a. The cooling water enters the lower water tank 12 from the cooling water inlet 103a, then flows upward from each row of cooling water to the upper water tank 11, and finally flows out from the cooling water return port 104a provided at the Nth row of cooling water pipes 102a.

[0213] Further, considering that the flue gas temperature is high near the flue gas inlet 4 and the cooling water consumption is large, while the flue gas temperature is low far from the flue gas inlet 4 and the cooling water consumption is small. In order to further reduce the cooling water consumption of the low-temperature condensation module 1, in the embodiment of the present application, along the direction from the flue gas inlet 4 to the outlet, the opening sizes of the connections between the lower water tank 12 and each row of cooling water pipes 102a are sequentially reduced, so that the cooling water volumes of each row of cooling water pipes 102a from the flue gas inlet 4 to the outlet direction are sequentially reduced, thereby realizing the overall water consumption of the low-temperature condensation module 1.

[0214] In addition, as shown in Figure 3C 、 4C 、5C, and 6C, the cooling water inlet 103a and the cooling water return port 104a are both arranged on opposite sides, so that the running distances and resistances of the cooling water in each parallel-flowing branch water pipe 1033 are the same, to ensure that the water flow rates in each parallel branch water pipe 1033 are the same and their cooling efficiencies for the corresponding flue gas are the same.

[0215] In addition, in order to ensure the overall aesthetic appearance of the purification equipment in the present application, a closed grille cover is installed on the outer side of the lower box plate 1012 to cover the water tank or elbow 105 exposed at the bottom of the box body 101.

[0216] The embodiment of the present application also provides a low-temperature condensation module 1 with a demisting, water collecting, and water blocking plate structure.

[0217] The flue gas velocity of the flue gas discharged from the cement kiln is high, and the heat exchange and condensation time through the low-temperature condensation module 1 is short. If the ammonia-containing condensate in the flue gas does not completely flow along the cooling water pipe 102a to the bottom of the device for external discharge, the ammonia-containing condensate will be discharged to the outside from the flue gas outlet 5, causing pollution. Therefore, in this embodiment, a demisting, water-collecting and water-blocking plate 13 is arranged at the flue gas outlet to further collect the moisture in the flue gas cooled to the dew point.

[0218] In order to further ensure that the ammonia-containing condensate will not be discharged to the outside from the flue gas outlet 5, in the embodiment of the present application, as Figure 3A shown, a plurality of vertically arranged demisting, water-collecting and water-blocking plates 13 are arranged at the flue gas outlet 5. The plate surface of the demisting, water-collecting and water-blocking plate 13 is a folding plate with a plurality of folding angles. After the flue gas is discharged from the last row of cooling water pipes 102a, it will pass through the demisting, water-collecting and water-blocking plate 13. Under the action of the folding surface of the folding plate, the velocity of the flue gas will decrease, and the condensate in the flue gas will adhere to the surface of the demisting, water-collecting and water-blocking plate 13 and flow down along the surface of the demisting, water-collecting and water-blocking plate 13 to the bottom of the device. By arranging the demisting, water-collecting and water-blocking plate 13, the condensate in the flue gas can be blocked from being discharged to the outside from the flue gas outlet.

[0219] Furthermore, the folding plate at least includes a pair of folding angles bent in opposite directions. In this way, the travel distance of the flue gas on the folding plate can be increased, which is beneficial to the collection of the moisture mixed in the flue gas.

[0220] As a preferred embodiment, a straight plate section is provided at a section of the folding plate close to the flue gas outlet, and its function is to guide the flue gas to flow along the demisting, water-collecting and water-blocking plate 13. Furthermore, at least part of the demisting, water-collecting and water-blocking plate 13 is formed with oblong holes extending vertically along the surface of the demisting, water-collecting and water-blocking plate 13 as drainage holes. The condensate adhering to the surface of the demisting, water-collecting and water-blocking plate 13 will flow down along the oblong holes to the bottom of the device for external discharge. Preferably, the oblong holes extend from the upper end to the lower end of the folding plate.

[0221] In order to further improve the safety of flue gas discharge, a wire mesh 14 is arranged outside the demisting, water-collecting and water-blocking plate 13 to provide a final barrier to the condensate in the flue gas.

[0222] In summary, the self-sustaining one-step purification equipment provided by the present application is applied to flue gas purification treatment scenarios such as cement kilns, power plants or coal yards, and can effectively reduce the contents of escaped ammonia, SO 2 , NOx, CO 2 and the dust content in the discharged flue gas.

[0223] In an embodiment of the purification equipment of the present application, when the flue gas inlet temperature of the flue gas is 105 °C, the moisture content of the flue gas is 9.5%, the escaped ammonia is 20 mg / m 3 , SO 2 content is 15 mg / m3 , NOx content is 38 mg / m 3 , CO 2 concentration is 20.5%, dust content is 6 mg / m 3 , when the inlet water temperature of the cooling water is 28°C,

[0224] (1) The flue gas outlet temperature is 60°C, the moisture content of the flue gas is 6.5%, the escaped ammonia is 6 mg / m 3 , SO 2 content is 5 mg / m 3 , NOx content is 34 mg / m 3 , CO 2 concentration is 18.5%, dust content is 3 mg / m 3 , and the outlet water temperature of the cooling water is 46°C.

[0225] (2) When increasing the cooling water volume in the low-temperature condensation module to make the flue gas outlet temperature of the purification equipment 50°C, the moisture content of the flue gas is 5.0%, the escaped ammonia is 3 mg / m 3 , SO 2 content is 2 mg / m 3 , NOx content is 32 mg / m 3 , CO 2 concentration content is 17.5%, dust content is 2 mg / m 3 , and the outlet water temperature of the cooling water is 41°C.

[0226] In another embodiment of the purification equipment of the present application, when the flue gas temperature at the flue gas inlet is 150°C, the moisture content of the flue gas is 7.5%, the escaped ammonia is 80 mg / m 3 , SO 2 content is 150 mg / m 3 , NOx content is 40 mg / m 3 , CO 2 concentration is 21.0%, dust content is 5 mg / m 3 , when the inlet water temperature of the cooling water is 28°C,

[0227] the flue gas outlet temperature is 65°C, the moisture content of the flue gas is 6.0%, the escaped ammonia is 15 mg / m 3 , SO 2 content is 42 mg / m 3 , NOx content is 36 mg / m 3 , CO 2 concentration is 19.0%, dust content is 3 mg / m 3 , and at this time the outlet water temperature of the cooling water is 65°C.

[0228] For the case where the flue gas inlet air temperature is relatively high, or the moisture content of the flue gas is relatively low, or the escaped ammonia content at the flue gas inlet is relatively high, in order to further improve the purification efficiency of escaped ammonia, as Figure 1B and Figure 2A shown, an embodiment of the present application provides a self-sustaining one-step purification device with an atomization device. The atomization device 3 is used to spray atomized water towards the flue gas inlet 4. The installation position of the atomization device 3 is at the flue gas inlet 4. More specifically, the atomization device 4 is arranged at the trapezoidal joint at the connection position between the flue gas discharge port of the cement kiln and the flue gas inlet 4 of the purification device. However, it should be noted that the installation position of the atomization device 3 is not limited to the flue gas inlet 4. For example, in some other embodiments, the atomization device 3 can also be arranged at the flue gas discharge port of the cement kiln or a more forward position. Spraying atomized water towards the flue gas inlet can increase the water content in the flue gas. The specific principle is as follows: Due to the high temperature of the flue gas, the atomized water will be evaporated into water vapor by the high temperature of the flue gas after entering the flue gas, thus increasing the water vapor content in the flue gas. When the water vapor content in the flue gas is relatively low, spraying atomized water through the atomization device 3 can increase the water vapor content in the flue gas, thereby improving the ammonia removal efficiency. In addition, a medicament (a medicament helpful for ammonia removal, denitration, and desulfurization) can also be added to the atomized water. By adding the medicament in the form of atomized water, the medicament can be fully contacted with the flue gas, further improving the cleanliness of the discharged flue gas. Finally, the atomized water can also cool down the flue gas, reducing the working pressure of the subsequent low-temperature condensation module 1.

[0229] The atomization device includes an atomization water tank, a spraying system, and a spraying water pipe connected in sequence. The atomization water tank is connected to a water source. The spraying water pipe is arranged at the flue gas inlet and is used to spray atomized water towards the flue gas inlet.

[0230] Further, the atomization device further includes an atomized water flow control mechanism for controlling the water volume of the spraying water pipe spraying atomized water towards the flue gas inlet.

[0231] When the flue gas air temperature at the flue gas inlet is greater than 120 °C, or the moisture content of the flue gas at the flue gas inlet is less than 8%, or the escaped ammonia at the flue gas inlet is 100 mg / m 3 ³, start the atomization device.

[0232] When the SO 2 content at the flue gas inlet is greater than 100 mg / m 3 ³, start the atomization device and add a desulfurization medicament to the atomized water; and / or when the Nox content at the flue gas inlet is greater than 50 mg / m 3 ³, start the atomization device and add a denitration medicament to the atomized water.

[0233] In an embodiment of the purification equipment of the present application, when the flue gas temperature at the flue gas inlet is 150 °C, the moisture content of the flue gas is 7.5%, the escaped ammonia is 80 mg / m 3 、SO 2 content is 150 mg / m 3 、NOx content is 40 mg / m 3 、CO 2 concentration is 21.0%, the dust content is 5 mg / m 3 , and the water temperature at the inlet of the cooling water is 28 °C,

[0234] the atomizing device 3 is activated, the moisture content of the inlet flue gas is adjusted to 9.0%, the inlet flue gas temperature is reduced to 128 °C, and the cooling water flow rate is increased so that when the flue gas outlet temperature of the purification equipment is 55 °C, the moisture content of the flue gas is 5.0%, the escaped ammonia is 4 mg / m 3 、SO 2 18 mg / m 3 、NOx content is 34 mg / m 3 、CO 2 concentration is 17.8%, the dust content is 1.5 mg / m 3 , and the water temperature at the outlet of the cooling water is 48 °C at this time.

[0235] As a preferred embodiment of the present application, the purification equipment further includes a spray cleaning device 2. Since the flue gas contains particulate matter, the particulate matter will adhere to the surface of the cooling water pipe 102 of the low-temperature condensation module 1 and is difficult to remove due to the long-term contact with the flue gas, reducing the heat exchange efficiency of the low-temperature condensation module 1 (i.e., the cooling efficiency of the flue gas). Therefore, as Figure 1B shown, water is sprayed through the spraying device 2 at the connection between the flue gas outlet 5 of the cement kiln and the ammonia removal device. The sprayed water is in a columnar shape and is sprayed onto the flue gas port, and is washed onto the surface of the cooling water pipe fittings by the rapidly flowing flue gas blown out from the flue gas outlet 5 of the cement kiln, washing away the particulate matter adhering to the surface of the pipe fittings.

[0236] The embodiment of the present application also provides a purification process using the above self-sustaining one-step purification equipment for purifying the flue gas of the flue gas emission equipment to be purified. The purification process mainly includes the following steps:

[0237] Install the self-sustaining one-step high-efficiency purification equipment at the flue gas outlet of the flue gas emission equipment to be purified, and seal the flue gas inlet of the self-sustaining one-step high-efficiency purification equipment with the flue gas outlet of the flue gas emission equipment to be purified;

[0238] Start the self-sustaining one-step high-efficiency purification equipment to work. By cooling the flue gas, the water vapor in the flue gas is condensed into condensed water, and the ammonia and acidic pollutants contained in the flue gas dissolve in the condensed water to undergo an acid-base neutralization reaction to form non-volatile salts that are easily soluble in the condensed water.

[0239] To improve the ammonia removal rate, further, the purification process further includes: by providing an atomizing device at the flue gas inlet, spraying atomized water at the flue gas inlet to increase the water vapor content in the flue gas. Experiments have proved that the ammonia removal rate can be greatly improved by increasing the water vapor content in the flue gas.

[0240] Since the flue gas contains particulate matter, the cooling water pipe 102 of the low-temperature condensation module 1 is in long-term contact with the flue gas, resulting in particulate matter adhering to the surface of the cooling water pipe fittings and being difficult to remove, reducing the heat exchange efficiency of the low-temperature condensation module 1 (i.e., the cooling efficiency of the flue gas). For this reason, the purification process further includes: spraying water through the spraying device 2 at the connection between the outlet 5 of the cement kiln flue gas and the inlet of the self-sustaining one-step purification device. The sprayed water is sprayed in a columnar shape onto the flue gas port and is washed onto the surface of the cooling water pipe fittings by the rapidly flowing flue gas blown out from the outlet 5 of the cement kiln flue gas, washing away the particulate matter adhering to the surface of the pipe fittings.

[0241] In addition, the purification process further includes: treating the salt-containing condensed water collected at the bottom of the self-sustaining one-step high-efficiency purification device into purified water that can be recycled or discharged externally and high-concentration salt-containing water by membrane separation, and spraying the high-concentration salt-containing water onto the grate cooler of the flue gas emission device to be purified. The advantages of this step have been described above and will not be elaborated here.

[0242] The embodiment of the present application further provides a modular purification device, modularizing the purification device in the above embodiment. The modular purification device includes a plurality of purification device sub-modules, and the plurality of purification device sub-modules can be arranged in parallel and / or in series. Standardize the sub-modules, and determine the number of sub-modules and the connection method between the sub-modules according to requirements and on-site layout.

[0243] Specifically, in an embodiment of the present application, one purification device can be made into two purification device sub-modules. During on-site installation, the two purification device sub-modules are placed side by side. Further, to ensure the connection reliability between the two sub-modules, the two purification device sub-modules can be connected by bolts or welding.

[0244] In addition, the sub-modules can also be placed at intervals. The outlet 5 of the cement kiln flue gas is split into each branch pipe and enters each sub-module respectively, and finally the flue gas of all sub-modules is collectively discharged.

[0245] Since the sub-modules are of standardized design, when the actual application scenario exceeds the purification capacity of the sub-modules, a plurality of sub-modules can be connected in series along the flue gas flow direction for use.

[0246] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various modifications and changes can be made to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A self-cleaning self-sustaining one-step purification device, characterized in that, it is used for purifying flue gas containing water vapor, ammonia and acidic pollutants; the purification device includes: a box body, the box body has a flue gas inlet and a flue gas outlet, and a flue gas passage formed from the flue gas inlet to the flue gas outlet; a low-temperature condensation module, which communicates with a cooling water inlet and a cooling water return port; the low-temperature condensation module includes a cooling water pipe bundle vertically arranged and arranged in an array in the flue gas passage, and end joint assemblies connected to the upper and lower ends of the cooling water pipe bundle. The end joint assemblies and the cooling water pipe bundle together constitute a cooling water circulation pipeline for cooling water to flow from the cooling water inlet to the cooling water return port; the low-temperature condensation module cools and condenses the flue gas entering the flue gas passage from the flue gas inlet, condenses the water vapor into condensed water, and the ammonia and the acidic pollutants dissolve in the condensed water and undergo an acid-base neutralization reaction in the condensed water to form non-volatile salts that are easily soluble in the condensed water; a spray washing device, which is arranged at the flue gas inlet and is used for spraying cleaning water at the flue gas inlet, and the cleaning water quickly enters the low-temperature condensation module along with the flue gas and wind to wash the surface of the water pipes of the cooling water pipe bundle; the cooling water pipe is an arc rhombus cooling water pipe, and the cooling water pipe bundle is arranged in a staggered row pipe bundle array; the cooling water pipe bundle is divided into several cooling water pipe groups along the flue gas flow direction, and each cooling water pipe group includes multiple rows of cooling water pipes arranged along the flue gas flow direction. The adjacent two rows of cooling water pipes in the multiple rows of cooling water pipes are staggered in the flue gas flow direction and there is no gap between the orthographic projection surfaces.

2. The self-cleaning self-sustaining one-step purification device according to claim 1, characterized in that, it further includes an atomization device, which is arranged at the flue gas inlet and is used for spraying atomized water at the flue gas inlet to increase the water vapor content in the flue gas.

3. The self-cleaning self-sustaining one-step purification device according to claim 2, characterized in that, pharmaceuticals for ammonia removal and / or desulfurization and / or denitration are added to the atomized water of the atomization device.

4. The self-cleaning self-sustaining one-step purification device according to claim 1, characterized in that, the layout dimensions of the cooling water pipe unit are in the range of: C = 1.8A~2A; D = 0.8B~1.5B; wherein, A is the maximum width dimension of the pipe cross-section; B is the maximum length dimension of the pipe cross-section; C is the center distance dimension of the pipe cross-sections of two adjacent cooling water pipes in the same row; D is the center distance dimension of the pipe cross-sections of adjacent rows of cooling water pipes.

5. The self-cleaning self-sustaining one-step purification device according to claim 4, characterized in that, the arc rhombus cooling water pipe includes: a cooling water pipe body, the cross-section of the cooling water pipe body is in the shape of an arc rhombus, the two ends of its short diagonal are arc ends respectively, and the two ends of the long diagonal are tip ends respectively; the arc ends at the two ends of the short diagonal and the tip ends at the two ends of the long diagonal are respectively connected by straight edges, and the straight edges are tangent to the arc lines of the arc ends.

6. The self-cleaning self-sustaining one-step purification equipment according to claim 5, characterized in that, the arc ends at both ends of the short diagonal are concentrically arranged; and / or, the midpoint connection line of the arc ends at both ends of the short diagonal is perpendicular to the connection line of the tips at both ends of the long diagonal.

7. The self-cleaning self-sustaining one-step purification equipment according to claim 1, characterized in that, the end joint assembly includes an upper end joint assembly and a lower end joint assembly. The upper end joint assembly and the lower end joint assembly are alternately arranged in sequence above and below the cooling water pipe bundle along the flue gas flow direction, and each end joint penetrates through the ends of multiple rows of cooling water pipes to form a parallel pipeline in the cooling water pipe bundle for at least two rows of parallel water flows to flow in the same direction; the upper end joint assembly is an upper water collecting tank, and the lower end joint assembly is a lower water collecting tank. The upper water collecting tank includes a plurality of upper water collecting tank parts arranged along the flue gas flow direction above the cooling water pipe bundle as the end joints. The lower water collecting tank includes a plurality of lower water collecting tank parts arranged along the flue gas flow direction below the cooling water pipe bundle as the end joints. The multiple rows of cooling water pipes penetrated by each water collecting tank part include a water inlet pipeline and a water outlet pipeline arranged side by side along the flue gas flow direction, and the number of rows of the water inlet pipeline and the water outlet pipeline is the same; one of the upper water collecting tank and the lower water collecting tank further includes a cooling water inlet tank communicated with the cooling water inlet, and the other further includes a cooling water return tank communicated with the cooling water return port. The cooling water inlet tank and the cooling water return tank both correspondingly penetrate through at least two rows of cooling water pipes; the cooling water pipe bundle is divided into multiple cooling water pipe groups along the flue gas flow direction. Each cooling water pipe group includes multiple rows of cooling water pipes arranged along the flue gas flow direction, and each cooling water pipe group corresponds to communicate with a group of the cooling water inlet and the cooling water return port. The cooling water flows between multiple cooling water pipe groups are not communicated in the cooling water pipe bundle.

8. The self-cleaning self-sustaining one-step purification equipment according to claim 7, characterized in that, the cooling water flow rate of the cooling water pipe group near the flue gas outlet is less than the cooling water flow rate of the cooling water pipe bundle near the flue gas inlet.

9. The self-cleaning self-sustaining one-step purification equipment according to claim 8, characterized in that, it further includes a cooling water inlet main pipe, and the cooling water inlet main pipe is communicated with each cooling water inlet through a flow regulating valve.

10. The self-cleaning self-sustaining one-step purification equipment according to claim 1, characterized in that, it further includes a condensate water collecting device arranged at the bottom of the low-temperature condensation module for collecting the condensate water, and the condensate water collecting device is connected to a condensate water discharge port.

11. A purification process using the self-cleaning self-sustaining one-step purification equipment according to any one of claims 1-10, characterized in that, it includes the following steps: Install the self-cleaning self-sustaining one-step purification equipment at the flue gas outlet of the flue gas emission equipment to be purified, and seal the flue gas inlet of the self-cleaning self-sustaining one-step purification equipment with the flue gas outlet of the flue gas emission equipment to be purified; Start the self-cleaning self-sustaining one-step purification equipment to work. By cooling the flue gas, the water vapor in the flue gas is condensed into condensed water, and the ammonia and acidic pollutants contained in the flue gas are dissolved in the condensed water to undergo an acid-base neutralization reaction to generate non-volatile salts that are easily soluble in the condensed water; Spray cleaning water at the flue gas inlet, and the cleaning water flushes the surface of the cooling water pipe of the low-temperature condensation module along with the flue gas to wash away the particulate matter adhered to the surface of the water pipe.

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