System for preparing wet desulfurization agent by using semi-dry desulfurization ash of circulating fluidized bed

Abstract

The utility model discloses a system utilizing circulating fluidized bed semi-dry desulfurization ash to prepare a wet desulfurization agent, which comprises three groups of assembly steel frames and a wet desulfurization agent preparation device, the three groups of assembly steel frames are distributed from top to bottom, the three groups of assembly steel frames form a mounting frame with a three-layer structure, and the wet desulfurization agent preparation device is arranged on the mounting frame. The wet desulfurization agent preparation device is distributed on a mounting frame with a three-layer structure, the wet desulfurization agent preparation device comprises a slurrying tank for reacting cane sugar with desulfurization ash generated by a circulating fluidized bed semi-dry method, and a liquid outlet of the slurrying tank is communicated with a filtering device through a slurrying pump. According to the system for preparing the wet desulfurizer by using the semi-dry desulfurization ash of the circulating fluidized bed, the high-quality wet desulfurizer can be prepared, the desulfurization ash resource is effectively utilized, the effects of resource reduction and waste control by waste are realized, and meanwhile, the system is integrated in the skid-mounted module, so that the problems of long system design period, low cost and the like are solved. The manufacturing and mounting period is long; and the occupied area is large.

Description

Technical Field

[0001] The utility model relates to the technical field of preparing wet desulfurization agents from semi-dry desulfurization ash, and particularly relates to a system for preparing wet desulfurization agents by using semi-dry desulfurization ash of a circulating fluidized bed. Background Technique

[0002] The circulating fluidized bed flue gas desulfurization technology is developed by Lurgi Company in Germany based on the circulating fluidized bed technology. By recycling the absorbent multiple times, the contact time between the absorbent and the flue gas is extended, and the utilization rate of the absorbent is improved. In recent years, a large number of desulfurization projects have adopted this method. The main process is as follows: The flue gas coming out of the boiler or incinerator is mixed with slaked lime in the circulating fluidized bed. SO2 and other acidic gases in the flue gas react with the slaked lime and are absorbed to achieve desulfurization. The flue gas is dust-removed by a dust collector and discharged after reaching the standard. There are a hopper chute and a circulating ash chute under the cloth bag hopper, and the unreacted absorbent is sent back to the fluidized bed for recycling. The recycling of the absorbent can maximize the utilization of the absorbent and reduce the consumption of fresh lime. However, even so, a large amount of unreacted calcium hydroxide still remains in the semi-dry desulfurization ash of the circulating fluidized bed. Research shows that the particles with a fine particle size in the range of 0.076 mm - 0.154 mm in the semi-dry desulfurization ash account for 57% - 64%. Its main components include 15 - 30 wt% of CaSO3·1 / 2H2O, 21 - 50 wt% of CaSO4·2H2O, and 11 - 30 wt% of Ca(OH)2, and the moisture content is about 1%. The desulfurization ash also contains a large amount of aluminum oxides, silicon oxides, and various heavy metal elements such as Zn, Cu, Cd, Mo, Cr, Mn, and Ni. The desulfurization ash is difficult to utilize, and most of it can only be landfilled. However, due to its strong alkalinity and fine particles, landfilling is more likely to cause environmental pollution. Therefore, the resource utilization of desulfurization ash has very important practical significance.

[0003] Using the semi-dry desulfurization ash of the circulating fluidized bed directly as a desulfurizing agent for wet desulfurization can effectively utilize resources and at the same time reduce the amount of semi-dry desulfurization ash of the circulating fluidized bed. However, due to the complex composition of the semi-dry desulfurization ash of the circulating fluidized bed and the large fluctuations in the content of each component, its properties are extremely unstable, and the effective calcium content and stability for wet desulfurization restrict its application as a wet desulfurization agent.

[0004] Due to the different scales of each manufacturer in the semi-dry desulfurization of the circulating fluidized bed, the output of desulfurization ash is also different. For the utilization of desulfurization ash, it is often necessary to design different scales of tanks, pump bases according to the specific output, and fabricate and install them on-site. Since the design drawings vary with the project, there are problems such as a long design cycle, a long fabrication and installation cycle, and a large floor area.

[0005] Therefore, a system for preparing wet desulfurization agents by using semi-dry desulfurization ash of a circulating fluidized bed is proposed. Summary of the Invention

[0006] The purpose of the present utility model is to provide a system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash, so as to solve or at least alleviate one or more of the above problems and other problems existing in the prior art.

[0007] In order to achieve the above purpose, the main technical solutions adopted by the present utility model include:

[0008] A system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash, comprising an assembly steel frame and a wet desulfurization agent preparation device. There are three groups of the assembly steel frames, which are distributed from top to bottom. The three groups of the assembly steel frames form an installation frame with a three-layer structure. The wet desulfurization agent preparation device is distributed on the installation frame with a three-layer structure. The wet desulfurization agent preparation device includes a pulping tank for the reaction of sucrose and desulfurization ash generated by the circulating fluidized bed semi-dry method. The liquid outlet of the pulping tank is connected to a filtering device through a pulp pump. The liquid outlet of the filtering device is connected to the precipitation tank through a pipeline. The outlet of the precipitation tank is connected to the feeding port of a vacuum belt filter through a slurry pump. The liquid discharge port of the vacuum belt filter is connected to the liquid inlet of the pulping tank through a filtrate pump. The solid discharge port of the vacuum belt filter is connected to the feeding port of the drying device through a pipeline.

[0009] In a system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, a stirrer for stirring the inside of the pulping tank is fixedly installed on the pulping tank, and the rotation speed of the stirrer is 44 r / min - 67 r / min.

[0010] In a system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, an ultrasonic generator with a frequency of 20 kHz - 60 kHz is installed at the bottom of the pulping tank.

[0011] In a system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, the filtering device is arranged above the precipitation tank, and the filtering device is a vibrating screen with 200 meshes - 350 meshes.

[0012] In a system for preparing a wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, wherein the drying device includes a first housing and a second housing, the second housing is sleeved inside the first housing, a drying medium conveying channel is left between the first housing and the second housing, a screw conveyor is provided inside the second housing, and when the calcium carbonate filter cake enters the inside of the second housing, it is sent by the screw conveyor to the discharge port of the second housing, and the drying medium dehydrates the calcium carbonate by heating the wall surface of the second housing.

[0013] In a system for preparing a wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, wherein the three sets of assembly steel frames have lengths, widths and heights of 5898 - 12032 mm, 2352 mm, and 2385 mm respectively.

[0014] In a system for preparing a wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, wherein the pulp tank, the pulp pump, the sedimentation tank and the slurry pump are all installed on the assembly steel frame of the third layer;

[0015] The vacuum belt filter and the filtrate pump are both installed on the assembly steel frame of the second layer;

[0016] The drying device is installed on the assembly steel frame of the first layer.

[0017] In a system for preparing a wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to the present utility model, wherein a maintenance ladder is installed on the mounting frame with a three-layer structure.

[0018] The present utility model at least has the following beneficial effects:

[0019] The circulating fluidized bed semi-dry desulfurization ash can be used to prepare a high-quality wet desulfurization agent through this system, effectively utilize the desulfurization ash resources, achieve the effects of resource reduction and treating waste with waste. At the same time, this system is integrated in the skid-mounted module, solving the problems of long system design cycle, long manufacturing and installation cycle, and large floor area. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present application, and form a part of the present application. The schematic embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0021] Figure 1 It is a schematic diagram of the pipeline connection principle of the present utility model;

[0022] Figure 2 It is a front view structural schematic diagram of the present utility model;

[0023] Figure 3 The front view structural schematic diagram of the first layer of the present utility model;

[0024] Figure 4 The top view structural schematic diagram of the first layer of the present utility model;

[0025] Figure 5 The front view structural schematic diagram of the second layer of the present utility model;

[0026] Figure 6 The top view structural schematic diagram of the second layer of the present utility model;

[0027] Figure 7 The front view structural schematic diagram of the third layer of the present utility model;

[0028] Figure 8 The top view structural schematic diagram of the third layer of the present utility model.

[0029] Explanation of the reference numerals in the attached drawings:

[0030] 1. Pulping tank; 2. Ultrasonic generator; 3. Stirrer; 4. Pulping pump; 5. Pipeline; 6. Filter device; 7. Settling tank; 8. Slurry pump; 9. Vacuum belt filter; 10. Drying device; 11. Filtrate pump; 12. Maintenance ladder. Specific implementation manners

[0031] The following will be combined with the drawings and embodiments to detail the implementation manners of the present application, so as to fully understand how the present application uses technical means to solve technical problems and achieve the realization process of technical effects and implement accordingly.

[0032] Please refer to Figures 1 to 8 As shown, in the embodiment of the present utility model,

[0033] A system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash includes an assembly steel frame and a wet desulfurization agent preparation device. There are three groups of assembly steel frames, which are distributed from top to bottom. The three groups of assembly steel frames form an installation frame with a three-layer structure. The wet desulfurization agent preparation device is distributed on the installation frame with a three-layer structure. Among them, the three groups of assembly steel frames are made of steel structures with lengths, widths and heights of 5898 - 12032 mm, 2352 mm and 2385 mm respectively. The bottom layer of the assembly steel frame is laid with grating plates. This size exactly meets the requirements of the length, width and height of automobile containers. After being transported to the site, the three groups of assembly steel frames with installed equipment can be assembled, and the system can be integrated into a skid-mounted module, solving the problems of long system design cycle, long production and installation cycle and large floor area.

[0034] The wet desulfurization agent preparation device is distributed on a mounting rack with a three-layer structure. The wet desulfurization agent preparation device includes a pulping tank 1 for the reaction of sucrose and desulfurization ash generated by the circulating fluidized bed semi-dry method. An ultrasonic generator 2 with a frequency of 20 kHz - 60 kHz is installed at the bottom of the pulping tank 1. By generating ultrasonic waves, the inclusion particles in the slurry are further dispersed, which is beneficial to the full reaction with the sucrose solution. A stirrer 3 for stirring the inside of the pulping tank 1 is fixedly installed on the pulping tank 1. The rotation speed of the stirrer 3 is 44 r / min - 67 r / min. The stirring part of the stirrer 3 is made of carbon steel lined with rubber to accelerate the reaction. The liquid outlet of the pulping tank 1 is connected to a filtering device 6 through a pulp pump 4. The filtering device 6 is a vibrating screen with a mesh size of 200 - 350 meshes. The filtering device 6 is arranged above a precipitation tank 7. The purified flue gas enters from the top of the precipitation tank 7. The liquid outlet of the filtering device 6 is connected to the precipitation tank 7 through a pipeline 5. The outlet of the precipitation tank 7 is connected to the inlet of a vacuum belt filter 9 through a slurry pump 8. The liquid discharge port of the vacuum belt filter 9 is connected to the inlet of the pulping tank 1 through a filtrate pump 11. The solid discharge port of the vacuum belt filter 9 is connected to the inlet of a drying device 10 through a pipeline 5. The pulping tank 1, the pulp pump 4, the filtering device 6, the precipitation tank 7 and the slurry pump 8 are all installed on the assembly steel frame of the third layer; the vacuum belt filter 9 and the filtrate pump 11 are both installed on the assembly steel frame of the second layer; the drying device 10 is installed on the assembly steel frame of the first layer. The pulping tank 1 and the precipitation tank 7 are made of carbon steel, and their inner walls are anticorrosively treated with wear-resistant glass flake resin. The pipeline 5 is made of carbon steel lined with rubber and is equipped with flanges, with a pipe diameter of DN50 - DN200; the pulp pump 4, the slurry pump 8 and the filtrate pump 11 are centrifugal pumps, and the motors are explosion-proof. The heat source of the drying device 10 is steam or hot flue gas, and the filtering width of the vacuum belt filter 9 is 1.3 - 4.5 m.

[0035] Specifically, the drying device 10 includes a first shell and a second shell. The second shell is sleeved inside the first shell. A drying medium conveying channel is left between the first shell and the second shell. A spiral conveyor is arranged inside the second shell. When the calcium carbonate filter cake enters the inside of the second shell, it is sent to the discharge port of the second shell by the spiral conveyor. The drying medium dehydrates the calcium carbonate by heating the wall surface of the second shell.

[0036] For the convenience of maintenance, a maintenance ladder 12 is installed on the mounting rack with a three-layer structure.

[0037] For the convenience of understanding the above technical solutions of the present invention, the working principle or operation method of the present invention in the actual process will be described in detail below.

[0038] The working principle of the present utility model is as follows: Sucrose reacts with the unreacted calcium hydroxide in the semi-dry desulfurized ash to produce calcium saccharate. Calcium saccharate is soluble in water, and through filtration, the separation of calcium saccharate from the desulfurized ash impurities is achieved. Then, purified flue gas is introduced into the calcium saccharate solution. CO2 in the flue gas can mineralize calcium saccharate to produce calcium carbonate, and the calcium carbonate desulfurizer for wet desulfurization can be obtained through pressure filtration and drying.

[0039] This system is divided into three-layer structure and can be transported to the site for installation in layers, saving time and site.

[0040] Specifically, it includes the following steps:

[0041] Step 1: Put the desulfurized ash and sucrose into the pulping tank 1. Under the combined action of the stirrer 3 and the ultrasonic generator 2, calcium hydroxide in the desulfurized ash reacts fully with sucrose to produce calcium saccharate.

[0042] Step 2: Calcium saccharate is transported to the filtering device 6 through the pulp pump 4. The insoluble impurities in the slurry are filtered by the filtering device 6. Since calcium saccharate is soluble in water, the insoluble impurities can be filtered by a sieve, and the filter residue can be landfilled. The filtrate enters the precipitation tank 7.

[0043] Step 3: Purified flue gas is introduced into the calcium saccharate solution in the precipitation tank 7. Since the flue gas contains CO2, calcium saccharate reacts with carbon dioxide to produce calcium carbonate.

[0044] Step 4: The calcium carbonate slurry is sent into the vacuum belt filter 9 through the slurry pump 8, and the filtrate containing sucrose and the calcium carbonate filter cake can be obtained. The filtrate is refluxed back to the pulping tank 1 through the filtrate pump 11, and the filter cake is dried by the drying device 10 to obtain the calcium carbonate desulfurizer.

[0045] The above description shows and describes several preferred embodiments of the present utility model. However, as mentioned above, it should be understood that the present utility model is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the inventive concept described herein through the above teachings or the technology or knowledge in related fields. And the changes and modifications made by those skilled in the art without departing from the spirit and scope of the present utility model shall fall within the protection scope of the appended claims of the present utility model.

Claims

1. A system for preparing wet desulfurization agent by using semi-dry desulfurization ash from circulating fluidized bed, characterized in that, It includes an assembled steel frame and a wet desulfurization agent preparation device. There are three groups of the assembled steel frames, which are distributed from top to bottom. The three groups of assembled steel frames form a mounting rack with a three-layer structure. The wet desulfurization agent preparation device is distributed on the mounting rack with a three-layer structure. The wet desulfurization agent preparation device includes a pulping tank (1) for the reaction of sucrose and desulfurization ash produced by the circulating fluidized bed semi-dry method. The liquid outlet of the pulping tank (1) is connected to a filtering device (6) through a pulp pump (4). The liquid outlet of the filtering device (6) is connected to a precipitation tank (7) through a pipeline (5). The outlet of the precipitation tank (7) is connected to the feed inlet of a vacuum belt filter (9) through a slurry pump (8). The liquid discharge outlet of the vacuum belt filter (9) is connected to the liquid inlet of the pulping tank (1) through a filtrate pump (11). The solid discharge outlet of the vacuum belt filter (9) is connected to the feed inlet of a drying device (10) through a pipeline (5).

2. The system for preparing a wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to claim 1, wherein: A stirrer (3) for stirring the inside of the pulping tank (1) is fixedly installed on the pulping tank (1), and the rotation speed of the stirrer (3) is 44 r / min - 67 r / min.

3. A system for preparing a wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to claim 2, characterized in that: An ultrasonic generator (2) with a frequency of 20 kHz - 60 kHz is installed at the bottom of the pulping tank (1).

4. A system for preparing wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to claim 3, characterized in that: The filtering device (6) is arranged above the precipitation tank (7), and the filtering device (6) is a vibrating screen with 200 - 350 meshes.

5. A system for preparing wet desulfurization agent using circulating fluidized bed semi-dry desulfurization ash according to claim 4, characterized in that: The drying device (10) includes a first shell and a second shell. The second shell is sleeved inside the first shell. A drying medium conveying channel is left between the first shell and the second shell. A spiral conveyor is arranged inside the second shell. When the calcium carbonate filter cake enters the inside of the second shell, it is sent to the discharge outlet of the second shell by the spiral conveyor. The drying medium dehydrates the calcium carbonate by heating the wall surface of the second shell.

6. The system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to claim 5, wherein: The length, width and height of the three groups of assembled steel frames are 5898 - 12032 mm, 2352 mm and 2385 mm respectively.

7. A system for preparing wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to claim 6, characterized in that: The pulping tank (1), the pulp pump (4), the filtering device (6), the precipitation tank (7) and the slurry pump (8) are all installed on the assembled steel frame of the third layer; The vacuum belt filter (9) and the filtrate pump (11) are all installed on the assembled steel frame of the second layer; The drying device (10) is installed on the assembled steel frame of the first layer.

8. A system for preparing a wet desulfurization agent by using circulating fluidized bed semi-dry desulfurization ash according to claim 1, characterized in that: A maintenance ladder (12) is installed on the mounting rack with a three-layer structure.

Images