A spraying device for flue gas desulfurization by large wet method in combined heat and power

Abstract

This utility model belongs to the field of waste gas treatment technology and discloses a spray device for wet desulfurization of flue gas from a cogeneration plant. It includes a spraying assembly for conveying and spraying limewater solution, and a tank assembly for the entry and exit of flue gas and limewater solution, providing a mixing and reaction site. A stirring assembly for increasing mixing uniformity is located in the middle of the tank assembly. The spraying assembly is located on one side of the tank assembly and connects the upper and lower parts of the tank assembly. The stirring assembly includes a drive shaft passing through a secondary tank mechanism and a main tank body. A rotary motor is located at the top of the drive shaft. Several stirring paddles are evenly distributed around the upper circumference of the drive shaft, pushing downwards, and several stirring blades are evenly distributed around the lower circumference of the drive shaft. This utility model's spray device for wet desulfurization of flue gas from a cogeneration plant adopts a layered design (upper stirring paddle + lower stirring blades), with an external rotary motor driving a multi-level stirring structure, extending the life of the rotary motor while ensuring a thorough and uniform desulfurization reaction.

Description

Technical Field

[0001] This utility model belongs to the field of waste gas treatment technology, and in particular relates to a spray device for wet desulfurization of flue gas from cogeneration plants. Background Technology

[0002] The wet flue gas desulfurization technology for combined heat and power (CHP) plants uses the limestone-gypsum method as its reaction principle, mainly comprising four systems: flue gas pretreatment, absorption tower reaction, oxidation crystallization, and wastewater treatment. High-temperature flue gas, after dust removal and cooling, enters the spray absorption tower, where it comes into countercurrent contact with atomized limestone slurry. Sulfur dioxide is absorbed, generating calcium sulfite. A forced oxidation system converts the calcium sulfite into gypsum byproduct, achieving sulfur resource recovery. The core advantage of this technology lies in its desulfurization efficiency of over 95%, while also adapting to the frequent load fluctuations of CHP units. A multi-layer spray layer and efficiency-enhancing ring design strengthen gas-liquid mass transfer, and a ridge-type demister controls droplet carryover. The generated desulfurized gypsum can be used in building material production, and the process wastewater is treated by neutralization and flocculation before being discharged in compliance with standards.

[0003] Comparing with Chinese Patent CN218688109U, a spray device for ultra-high efficiency wet desulfurization of flue gas from combined heat and power plants is disclosed. The device includes a spray tower with a fixed pipe in the middle. Inside the fixed pipe is a spray outlet pipe, one end of which extends out of the spray tower and connects to a water pump. Multiple bends are evenly arranged on the spray outlet pipe, and these bends are rotatably sealed to a rotating pipe. A water storage box is connected to the bottom of the rotating pipe, and a first and second diversion pipe are respectively arranged on both sides of the water storage box. First and second spray heads are evenly arranged on the first and second diversion pipes, respectively. A wastewater tank is located at the bottom of the spray tower. The spray area is expanded by using multiple diversion pipes and spray heads. The rotating pipe with a driven gear and a driving gear rotate the spray device, resulting in insufficient and uneven mixing of flue gas and liquid. The wastewater tank and circulating water pipe with a wastewater pump effectively conserve water resources.

[0004] However, the aforementioned patented motor and transmission are all located inside, which is prone to corrosion and damage, seriously affecting the service life of the motor. Moreover, the power is only used to agitate the spray, resulting in less agitation of the flue gas. This has a limited effect on increasing the uniform mixing of the cogeneration flue gas and lime water, reducing the reaction speed and efficiency. Therefore, a new device needs to be designed. Utility Model Content

[0005] The purpose of this invention is to provide a spray device for wet desulfurization of flue gas from combined heat and power plants, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A spraying device for wet desulfurization of flue gas in a combined heat and power plant includes a spraying assembly for conveying and spraying lime water solution, and a tank assembly for the entry and exit of flue gas and lime water solution and for providing a mixing and reaction site. A stirring assembly for increasing mixing uniformity is disposed in the middle of the tank assembly. The spraying assembly is located on one side of the tank assembly and connects the upper and lower parts of the tank assembly. The tank assembly includes a main tank body, a secondary tank mechanism is disposed at the top of the main tank body, an outlet pipe is disposed on one side of the secondary tank mechanism, and a discharge pipe is disposed at the bottom of the main tank body. A spraying device is installed on the discharge pipe. The system includes a discharge valve, an inlet pipe on one side of the bottom of the main housing, and an air inlet pipe above the inlet pipe. The spraying assembly includes a circulating pump with a filter head installed at the inlet end and a delivery pipe installed at the outlet end. A distribution mechanism for evenly spraying lime water solution in a ring is installed at the top of the delivery pipe. The stirring assembly includes a drive shaft passing through the auxiliary housing mechanism and the main housing. A rotary motor is installed at the top of the drive shaft. Several stirring blades are evenly distributed around the upper circumference of the drive shaft, pushing downwards. Several stirring blades are evenly distributed around the lower circumference of the drive shaft.

[0008] Furthermore: the auxiliary box mechanism includes an auxiliary box body, and several demisting plates are evenly distributed inside the auxiliary box body, the demisting plates being porous corrugated plates.

[0009] Furthermore: the main box is a cylindrical shape with a tapered bottom, and an observation window is provided at the front of the main box; the secondary box is a rectangular box shape.

[0010] Furthermore, the distributing mechanism includes a liquid equalization ring, and a plurality of spray heads are evenly distributed at the bottom of the liquid equalization ring.

[0011] Furthermore, the liquid distribution ring is circular, and the spray head and the liquid distribution ring are connected by a sealing thread.

[0012] Furthermore: the stirring paddle has four pieces arranged circumferentially and three layers arranged axially; the stirring blade has six pieces arranged circumferentially and four layers arranged axially.

[0013] Furthermore, the stirring blade is rectangular.

[0014] Compared with existing technologies, the beneficial effects are:

[0015] 1. The stirring assembly adopts a layered design (upper stirring paddle + lower stirring blade), and is driven by an external rotary motor to form a multi-level stirring structure (the blades are distributed circumferentially / axially), which extends the life of the rotary motor, forcibly disturbs the flue gas and lime water, breaks the limitations of traditional static reaction, significantly improves the gas-liquid contact area and reaction rate, and ensures that the desulfurization reaction is fully and uniform.

[0016] 2. Through the synergistic innovation of spray homogenization, dynamic stirring, gas-liquid separation optimization and anti-clogging design, the problems of uneven mixing, easy clogging and difficulty in recovering by-products in traditional wet desulfurization are solved. It has the advantages of high efficiency, stability and economy and is suitable for industrial flue gas treatment scenarios such as cogeneration.

[0017] 3. The annular liquid distribution ring of the spraying component, together with the spray head and the stirring component, forms a dual mixing mode of "top-down spraying + rotation stirring", avoiding dead zones in local reaction, and is especially suitable for the treatment of high-concentration flue gas.

[0018] 4. The conical structure at the bottom of the main box, combined with the circulation effect driven by the stirring blades, promotes the gypsum slurry to gather in a directional manner towards the central discharge pipe, preventing sedimentation and accumulation. The slurry can be discharged in a controlled manner through the bottom discharge valve, which facilitates subsequent dewatering and recycling, realizing the resource utilization of sulfur. The filter head intercepts impurities, reduces the risk of circulation pump blockage, and extends the equipment life. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a spray device for wet desulfurization of flue gas from a cogeneration plant, as described in this utility model.

[0020] Figure 2 This is an appearance drawing of a spray device for wet desulfurization of flue gas from a cogeneration plant, as described in this utility model.

[0021] Figure 3 This is a front perspective view of the tank assembly of a spray device for wet desulfurization of flue gas in a cogeneration plant, as described in this utility model.

[0022] Figure 4 This is an external view of the tank assembly of a spray device for wet desulfurization of flue gas in a cogeneration plant, as described in this utility model.

[0023] Figure 5 This is a schematic diagram of the spraying components of a spraying device for wet desulfurization of flue gas from a cogeneration plant, as described in this utility model.

[0024] Figure 6 This is a schematic diagram of the stirring assembly of a spray device for wet desulfurization of flue gas in a cogeneration plant, as described in this utility model.

[0025] In the attached diagram, the following are the reference numerals: 101, main housing; 102, liquid inlet pipe; 103, air inlet pipe; 104, discharge pipe; 105, discharge valve; 106, auxiliary housing; 107, air outlet pipe; 108, demister plate; 109, observation window; 201, circulating pump; 202, filter head; 203, liquid delivery pipe; 204, liquid equalization ring; 205, spray head; 301, drive shaft; 302, rotary motor; 303, stirring blade; 304, stirring paddle. Detailed Implementation

[0026] 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.

[0027] Please see Figures 1-6 A spraying device for wet desulfurization of flue gas in cogeneration includes a spraying assembly for conveying and spraying lime water solution, and a box assembly for the entry and exit of flue gas and lime water solution and providing a mixing and reaction site. A stirring assembly for rotating and stirring to increase the uniformity of mixing is provided in the middle of the box assembly. The spraying assembly is located on one side of the box assembly and connects the upper and lower parts of the box assembly.

[0028] In this embodiment: the box assembly includes a main box body 101, a secondary box mechanism is provided at the top of the main box body 101, an air outlet pipe 107 is provided on one side of the secondary box mechanism, a discharge pipe 104 is provided at the bottom of the main box body 101, a discharge valve 105 is installed on the discharge pipe 104, a liquid inlet pipe 102 is provided on one side of the bottom of the main box body 101, and an air inlet pipe 103 is provided above the liquid inlet pipe 102; the secondary box mechanism includes a secondary box body 106, and a plurality of demister plates 108 are evenly distributed vertically inside the secondary box body 106, the demister plates 108 are made of porous corrugated plates; the main box body 101 is a cylindrical shape with a tapered bottom, and an observation window 109 is provided at the front of the main box body 101. The auxiliary chamber 106 is rectangular. The lime water flows into the main chamber 101 from the inlet pipe 102 and submerges the filter head 202. The combined heat and power flue gas flows into the main chamber 101 from the bottom through the inlet pipe 103 and mixes with the sprayed lime water to react. The gas after reaction floats into the auxiliary chamber 106 and comes into contact with the demister plate 108, causing the droplets to collect and flow down. Together with the droplets after reaction, they fall to the bottom of the main chamber 101 and merge with the lime water. The clean gas flows out from the outlet pipe 107. The heavier gypsum slurry collects at the middle outlet pipe 104. When the outlet valve 105 is opened, the gypsum slurry is discharged along the outlet pipe 104.

[0029] In this embodiment: the spraying assembly includes a circulating pump 201, a filter head 202 is installed at the inlet end of the circulating pump 201, and a delivery pipe 203 is installed at the outlet end of the circulating pump 201. The top end of the delivery pipe 203 is provided with a distributing mechanism for uniformly spraying lime water in a ring. The distributing mechanism includes a liquid equalization ring 204, and a plurality of spray heads 205 are evenly distributed at the bottom of the liquid equalization ring 204. The liquid equalization ring 204 is circular, and the spray heads 205 and the liquid equalization ring 204 are connected by a sealing thread. The circulating pump 201 draws lime water from the main housing 101 through the filter head 202 and sends it into the liquid equalization ring 204 through the delivery pipe 203. Then, the lime water is evenly sprayed from the spray heads 205 at the bottom of the liquid equalization ring 204 into the main housing 101, where it mixes with the cogeneration flue gas to react.

[0030] In this embodiment: the stirring assembly includes a drive shaft 301 passing through the auxiliary box mechanism and the main box 101. A rotary motor 302 is provided at the top of the drive shaft 301. Several stirring paddles 304 are evenly distributed around the upper circumference of the drive shaft 301, pushing downwards. Several stirring blades 303 are evenly distributed around the lower circumference of the drive shaft 301. There are four stirring paddles 304 arranged circumferentially and three layers arranged axially. There are six stirring blades 303 arranged circumferentially and four layers arranged axially. The stirring blades 303 are rectangular strips. The rotary motor 302 drives the stirring paddles 304 to rotate through the drive shaft 301, pushing them downwards to form an up-and-down tumbling circulation stirring, accelerating the uniform mixing of the cogeneration flue gas and lime water liquid, speeding up the reaction. At the same time, it drives the stirring blades 303 to rotate, stirring the lime water liquid at the bottom of the main box 101 to form a circulation, so that the heavier gypsum slurry gathers at the middle discharge pipe 104.

[0031] Working principle: Lime water solution flows into the main chamber 101 through the inlet pipe 102 and submerges the filter head 202. The circulation pump 201 draws the lime water solution from the main chamber 101 through the filter head 202 and sends it into the equalization ring 204 through the delivery pipe 203. Then, the lime water solution is evenly sprayed into the main chamber 101 from the spray head 205 at the bottom of the equalization ring 204. The cogeneration flue gas flows into the main chamber 101 from the bottom through the air inlet pipe 103 and mixes with the sprayed lime water solution to react. At the same time, the rotary motor 302 at the top of the auxiliary chamber 106 drives the stirring paddle 304 to rotate through the drive shaft 301, pushing it downward to form an upper... The downward-turning agitator accelerates the uniform mixing of the cogeneration flue gas and lime water, speeding up the reaction. The reacted gas rises into the auxiliary chamber 106 and contacts the demister plate 108, causing the droplets to converge and flow downwards. Together with the reacted droplets, they fall to the bottom of the main chamber 101 and merge into the lime water. The clean gas flows out from the outlet pipe 107. The drive shaft 301 drives the agitator 304 to rotate while simultaneously driving the agitator blade 303 to rotate, stirring the lime water at the bottom of the main chamber 101 to form a circulation. This causes the heavier gypsum slurry to converge at the middle outlet pipe 104. The outlet valve 105 is then opened, and the gypsum slurry is discharged along the outlet pipe 104.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A spraying device for wet desulfurization of flue gas from a combined heat and power plant, comprising a spraying assembly for conveying and spraying lime water solution, characterized in that: It also includes a box assembly for the entry and exit of flue gas and lime water solution and for providing a mixing and reaction site. The box assembly is provided with a stirring component in the middle for rotating and stirring to increase the uniformity of mixing. The spraying component is provided on one side of the box assembly and connects the upper and lower parts of the box assembly. The box assembly includes a main box body (101), a secondary box mechanism is provided on the top of the main box body (101), an air outlet pipe (107) is provided on one side of the secondary box mechanism, a discharge pipe (104) is provided at the bottom of the main box body (101), a discharge valve (105) is installed on the discharge pipe (104), a liquid inlet pipe (102) is provided on one side of the bottom of the main box body (101), and an air inlet pipe (103) is provided above the liquid inlet pipe (102). The spraying assembly includes a circulating pump (201), a filter head (202) is installed at the inlet end of the circulating pump (201), a delivery pipe (203) is installed at the outlet end of the circulating pump (201), and a distribution mechanism for uniformly spraying lime water solution in a ring is provided at the top end of the delivery pipe (203). The stirring assembly includes a drive shaft (301) that passes through the auxiliary box mechanism and the main box (101). A rotary motor (302) is provided on the top of the drive shaft (301). Several stirring blades (304) are evenly distributed on the upper circumference of the drive shaft (301) and push downward. Several stirring blades (303) are evenly distributed on the lower circumference of the drive shaft (301).

2. The spray device for wet desulfurization of flue gas from a combined heat and power plant according to claim 1, characterized in that: The auxiliary box mechanism includes an auxiliary box body (106), and several demisting plates (108) are evenly distributed inside the auxiliary box body (106). The demisting plates (108) are made of porous corrugated plates.

3. The spray device for wet desulfurization of flue gas from a combined heat and power plant according to claim 2, characterized in that: The main box (101) is a cylindrical shape with a tapered bottom, and an observation window (109) is provided in front of the main box (101). The auxiliary box (106) is a rectangular box shape.

4. The spray device for wet desulfurization of flue gas from a combined heat and power plant according to claim 1, characterized in that: The distribution mechanism includes a liquid equalization ring (204), and a plurality of spray heads (205) are evenly distributed at the bottom of the liquid equalization ring (204).

5. A spray device for wet desulfurization of flue gas from a combined heat and power plant according to claim 4, characterized in that: The liquid distribution ring (204) is circular, and the spray head (205) and the liquid distribution ring (204) are connected by a sealing thread.

6. The spray device for wet desulfurization of flue gas from a combined heat and power plant according to claim 1, characterized in that: The stirring paddle (304) has four pieces arranged circumferentially and three layers arranged axially; the stirring blade (303) has six pieces arranged circumferentially and four layers arranged axially.

7. A spray device for wet desulfurization of flue gas from a combined heat and power plant according to claim 6, characterized in that: The stirring blade (303) is rectangular.

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