Kiln gas washing tower

Abstract

The utility model relates to the technical field of kiln gas washing towers, and discloses a kiln gas washing tower which is characterized in that a settling pond is used for placing muddy water and precipitating the muddy water, a washing tower is arranged on one side of the settling pond, pipelines are arranged on the other side of the settling pond, and the pipelines are communicated with the washing tower and used for conveying the muddy water into the washing tower; the kiln gas washing tower adopts muddy water and purified water for layered washing, the purified water is discharged circulating water and desalted concentrated water of a thermal power plant, wastewater resources of the whole plant are recycled, the use amount of fresh seawater and circulating water is reduced, meanwhile, the wastewater discharge amount is reduced, water is saved, emission is reduced, and the washing effect can be improved by adopting a staged washing mode; the dust content of the kiln gas at the outlet of the kiln gas washing tower is further reduced, so that the workload of the electric dust remover is reduced, the washing displacement of the electric dust remover is reduced, the temperature of the cooled kiln gas is further reduced, the suction rate of a compressor is improved, and the energy consumption of a compression process is reduced.

Description

Technical Field

[0001] This utility model relates to the field of kiln gas scrubbing tower technology, specifically a kiln gas scrubbing tower. Background Technology

[0002] A high-efficiency water-saving technology for kiln gas scrubbing involves constructing a turbid circulating water cooling tank. A separate turbid circulating water system is established for the kiln gas scrubbing tower in the lime production section. The circulating water in this system is the cooling water needed for further dust removal and cooling of the kiln gas during the lime digestion process. The cooling tank is divided into two compartments: one collects turbid water from the lime production section, which is then filtered through a horizontal flow sedimentation tank before gravity flow into a hot water tank. The water in the hot water tank is mainly used for lime sintering; a portion enters a PCF filter for further turbidity removal to meet water quality requirements; the remaining portion enters the turbid water cooling tower for cooling. After the water temperature drops to 27°C, it is sent to the lime production section for spraying and scrubbing the kiln gas. This technology achieves separate water use and multiple uses of a single water source, but the process flow is also relatively complex.

[0003] A method for recycling turbid water effectively reuses wastewater discharged from kiln gas scrubbing. The specific process involves turbid water discharged from the kiln gas scrubbing tower and electrostatic precipitator flowing by gravity into a turbid water circulation tank. The circulation tank is divided into multiple zones, enabling uninterrupted operation of water intake, sedimentation, effluent, and sludge removal. The suspended solids content in the effluent is less than 40 mg / L. There are two ways to utilize the turbid water: first, direct utilization after clarification, recovering its heat while reusing the turbid water by pressurizing it with a hot water pump and sending it to the ash-making process; second, reuse after cooling, using a turbid water circulation pump to send the clarified turbid water to a cooling tower for cooling, and then pressurizing it with a cold water pump before sending it to the kiln gas scrubbing water pipeline for kiln gas scrubbing. This process achieves the recycling of turbid water, but requires a high degree of sedimentation efficiency for the solid particles in the settled turbid water.

[0004] By optimizing the formulation and conducting process condition experiments of a composite water purification agent for kiln gas wastewater, and using COD removal rate as the evaluation index, relatively pure reclaimed water was obtained, meeting the requirements for recycling. Specifically, quicklime was added to the kiln gas wastewater and stirred for 30 minutes, then precipitant C was added and stirred at 60℃ for 15 minutes, followed by the addition of 0.1 mL of 0.5% cationic polyacrylamide and stirring for 10 minutes. After filtration and sampling analysis, the COD content was 3.5 mg / L, and the COD removal rate reached 98.1%. This technology requires a large amount of precipitant and other additives, resulting in high turbidity water purification costs, making it unsuitable for industrial production.

[0005] The above analysis shows that major alkali plants and related research institutions have conducted extensive research on the recycling and utilization of kiln gas scrubbing turbid water. However, specific applications still need to be tailored to the company's specific circumstances. The proposed process route for this project fully considers Haitian Company's actual production situation, adopting a staged washing method. While recycling turbid water from the lime process, it also utilizes wastewater resources such as circulating water drainage and demineralized water concentrate. This not only achieves water conservation and emission reduction but also improves the kiln gas scrubbing and cooling effect. The successful development of this project will further promote the development of Haitian Company. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a kiln gas scrubbing tower.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The sedimentation tank is used to put in turbid water and settle the turbid water. A washing tower is arranged on one side of the sedimentation tank, and pipes are provided on both sides of the sedimentation tank, and the pipes are connected to the washing tower for transferring turbid water into the washing tower.

[0009] As a further description of the above technical solution:

[0010] The washing tower is equipped with a primary washing unit and a secondary washing unit, which are connected by a pipe for transmitting kiln gas. The primary and secondary washing units are also connected above the primary and secondary washing units for transmitting turbid water.

[0011] As a further description of the above technical solution:

[0012] The secondary washing unit has a hole at the bottom for transmitting clean water, which is then transmitted into the secondary washing unit for secondary washing of kiln gas.

[0013] As a further description of the above technical solution:

[0014] An electrostatic precipitator is arranged on one side of the secondary washing unit, and the secondary washing unit is connected to the electrostatic precipitator. The electrostatic precipitator is used to remove dust from the kiln gas after the secondary washing unit.

[0015] As a further description of the above technical solution:

[0016] A compression assembly is arranged on one side of the electrostatic precipitator for compressing the kiln gas discharged from the electrostatic precipitator.

[0017] This utility model has the following beneficial effects:

[0018] 1. The kiln gas scrubbing tower adopts stratified scrubbing of turbid water and clean water. The clean water is the circulating water drainage and the concentrated water from the demineralized water of the thermal power plant, realizing the recycling of wastewater resources throughout the plant, reducing the consumption of fresh seawater and circulating water, and reducing wastewater discharge, thus saving water and reducing emissions.

[0019] 2. Using a staged washing method can improve the washing effect, further reduce the dust content of the kiln gas at the outlet of the kiln gas scrubbing tower, thereby reducing the workload of the electrostatic precipitator, reducing the amount of flushing water from the electrostatic precipitator, further reducing the temperature of the cooled kiln gas, increasing the compressor's air extraction capacity, and reducing the energy consumption of the compression process. Attached Figure Description

[0020] Figure 1 This is a flowchart of a kiln gas scrubbing tower proposed in this utility model.

[0021] Legend: 1. Turbid water; 2. Kiln gas; 3. Clean water; 4. Compression assembly; 5. Sedimentation tank; 6. Primary washing; 7. Secondary washing; 8. Electrostatic precipitator. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The utility model will be further described in detail below with reference to the accompanying drawings.

[0024] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0025] Reference Figure 1 The present invention provides an embodiment of a kiln gas scrubbing tower: a flowchart of a kiln gas scrubbing tower is provided. Turbid water 1 is pumped into a sedimentation tank 5 to treat the suspended solids in the turbid water 1 and to reduce the temperature of the turbid water 1 after sedimentation in the sedimentation tank 5. The turbid water 1 is then sent to the scrubbing tower for primary scrubbing 6 for the first scrubbing of the kiln gas 2 by the turbid water 1.

[0026] After primary washing 6, kiln gas 2 is introduced below primary washing 6 and flows counter-currently to cool the primary washing process. The washed turbid water 1 is discharged from the top of the washing tower into the sedimentation tank 5 for recycling. Solid particles settle freely in the sedimentation tank 5. Based on experimental results and theoretical calculations, the settling velocity and the location of particles (stagnation zone, transition zone, turbulent zone) are determined. The main influencing factors on particle settling and the settling efficiency of the sedimentation tank 5 are identified. This determines the flow velocity and settling time of the turbid water in the sedimentation tank to ensure the settling effect while meeting the required turbid water volume for primary kiln gas washing.

[0027] After passing through the primary washing stage 6, the kiln gas 2 enters the secondary washing stage 7 on the washing tower, and clean water 3 is poured in from below the secondary washing stage 7 to perform a second washing of the kiln gas.

[0028] After secondary washing in the scrubbing tower, the kiln gas 2 enters the electrostatic precipitator 8, and the purified water 3 is converted into turbid water 1 after secondary washing and then discharged into the sedimentation tank 5 through the top of the scrubbing tower for circulation.

[0029] After being dedusted by the electrostatic precipitator 8, the kiln gas 2 is discharged into the compression assembly 4 to compress the kiln gas 2, thereby reducing the energy consumption of the compression process.

[0030] Both kiln gas 2 and purified water 3 enter the sedimentation tank 5 for sedimentation after passing through primary washing 6 and secondary washing 7, in order to save water and further circulate water.

[0031] The primary washing stage 6 and the secondary washing stage 7 are used to further purify the kiln gas 2.

[0032] Turbid water 1, along with circulating water drainage and desalinated concentrated water, replaces fresh seawater as washing water for kiln gas 2. This further reduces the temperature of kiln gas 2 while meeting the existing production process requirements for dust removal, thereby increasing the air volume of the compressor.

[0033] The detailed implementation methods disclosed in this article omit the detailed descriptions of known functions and known components. In order to ensure the compatibility of the assemblies, the operating methods adopted are consistent with the pipe diameter parameters of the market.

[0034] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A kiln gas scrubbing tower, characterized in that: include: Sedimentation tank (5), the sedimentation tank (5) is used to put in turbid water (1) for sedimentation of turbid water (1), and a washing tower is arranged on one side of the sedimentation tank (5), and pipes are provided on both sides of the sedimentation tank (5), and the pipes are connected to the washing tower for transmitting turbid water (1) into the washing tower.

2. The kiln gas scrubbing tower according to claim 1, characterized in that: The washing tower is equipped with a primary washing (6) and a secondary washing (7), and the primary washing (6) and the secondary washing (7) are connected by a pipe for transmitting kiln gas (2), and a pipe for transmitting turbid water (1) is connected above the primary washing (6) and the secondary washing (7).

3. A kiln gas scrubbing tower according to claim 2, characterized in that: The secondary washing (7) has a hole at the bottom for transmitting clean water (3), and the clean water (3) is transmitted into the interior of the secondary washing (7) for secondary washing of kiln gas (2).

4. A kiln gas scrubbing tower according to claim 3, characterized in that: An electrostatic precipitator (8) is arranged on one side of the secondary washing (7), and the secondary washing (7) is connected to the electrostatic precipitator (8). The electrostatic precipitator (8) is used to remove dust from the kiln gas after the secondary washing (7).

5. A kiln gas scrubbing tower according to claim 4, characterized in that: A compression assembly (4) is arranged on one side of the electrostatic precipitator (8) for compressing the kiln gas (2) discharged from the electrostatic precipitator (8).

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