Flue gas semi-dry desulfurization system

Abstract

According to the semi-dry flue gas desulfurization system provided by the utility model, the desulfurization tower adopts double-sleeve arrangement, and the retention time of flue gas in a reactor can be greatly prolonged under the condition of the same sectional dimension of the reactor, so that the full contact time of a desulfurizing agent and the flue gas is prolonged, and the desulfurization reaction efficiency is improved; the desulfurization tower is provided with the flue gas leading-in section and the Venturi acceleration section, and meanwhile, the flue gas leading-in section is provided with the flow guide plate, so that flue gas can enter the desulfurization tower from bottom to top at an enough speed, and a reaction is fully carried out. According to the scheme, the double-fluid spray gun is arranged in front of the inlet of the desulfurizing tower, so that flue gas can be combined with atomized process water before entering the desulfurizing tower; the double-fluid spray gun is arranged at the rear end of the venturi acceleration section, so that after accelerated high-speed flue gas is combined with a large amount of fog drops, the temperature of the flue gas can be quickly reduced to be closer to the adiabatic saturation temperature of the flue gas, the desulfurization reaction is facilitated, and the reaction efficiency can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas desulfurization, in particular to a flue gas semi-dry desulfurization system. Background Art

[0002] The hazardous waste incineration flue gas generated after the incineration of hazardous waste contains many acidic substances including sulfur, which needs to be sent to the deacidification system for deacidification treatment. The existing deacidification treatment processes mainly include two processes: dry desulfurization and wet desulfurization. Among them, the conventional dry desulfurization system, due to efficiency and process characteristics requirements, the desulfurization tower is often designed to be relatively large, resulting in a heavier equipment structure, a larger footprint, and a higher investment cost. The equipment for wet desulfurization, such as the patent with publication number CN218358401U, is the wet desulfurization system currently in use by our company. It uses circulating alkaline liquid to spray and flush the flue gas in the wet washing process, so it is necessary to design a set of spray liquid circulation system for the spray washing process. At the same time, in actual use, according to relevant regulations, a set of wastewater treatment equipment is also required for the circulating liquid to avoid alkaline wastewater from polluting the environment. These supporting equipment also invisibly increase the investment cost and use cost of the system. Summary of the invention

[0003] In order to solve the problem of relatively high investment cost of desulfurization equipment in the prior art, the utility model provides a flue gas semi-dry desulfurization system, which has compact equipment, small footprint and low investment cost.

[0004] The structure of the utility model is as follows: a flue gas semi-dry desulfurization system, which comprises: a desulfurization tower, characterized in that it also comprises: a flue gas introduction section, a venturi acceleration section, a guide plate, a desulfurizer nozzle and a dual-fluid spray gun;

[0005] The desulfurization tower is a sleeve structure, which includes: an inner cylinder and an outer cylinder, wherein the outer cylinder is sleeved on the outside of the inner cylinder from top to bottom;

[0006] The top of the smoke introduction section is connected to the bottom inlet of the Venturi acceleration section, the bottom of the smoke introduction section is provided with an ash outlet, and the side wall of the smoke introduction section is provided with a smoke introduction port connected to the smoke channel of the incinerator;

[0007] The top outlet of the venturi acceleration section is connected to the bottom inlet of the inner cylinder, the top outlet of the inner cylinder is connected to the inner cavity of the outer cylinder, the inner wall of the outer cylinder and the outer wall of the inner cylinder form a flue gas channel, and the bottom end of the outer cylinder is provided with a total flue gas outlet connected to a flue gas dust removal device;

[0008] The dual-fluid spray gun is arranged in the Venturi acceleration section near the inner cylinder; the dual-fluid spray gun is connected to the process water supply device;

[0009] The desulfurizer nozzle is arranged in the Venturi acceleration section below the two-fluid spray gun; the desulfurizer nozzle is connected to the desulfurizer supply device;

[0010] The guide plate is arranged in the inner cavity of the flue gas inlet section, and the flue gas inlet channels are formed between adjacent guide plates.

[0011] It is further characterized in that:

[0012] The guide plate includes: an arc-shaped plate and a reinforcing rib;

[0013] The arc-shaped plates are of unequal length, and the arc-shaped flue gas inlet channels are formed between adjacent arc-shaped plates; the bottom of the flue gas inlet channel faces the flue gas inlet, and the top faces the bottom inlet of the Venturi acceleration section; the reinforcing rib is arranged on the plate surface of the arc-shaped plate facing the flue gas inlet;

[0014] The bottom of the arc-shaped plate is provided with ash leakage holes, and the ash leakage holes are arranged above the soot outlet of the flue gas inlet section;

[0015] The bottom of the flue gas inlet section is provided with an ash hopper that is wider at the top and narrower at the bottom. The ash hopper is arranged below the soot outlet, and the ash hopper is connected to the ash storage tank;

[0016] It further includes: a differential pressure measuring device and a temperature measuring device. The differential pressure measuring device is arranged between the flue gas channel at the flue gas inlet and the flue gas channel connected to the total flue gas outlet; the temperature measuring device is arranged on the flue gas channel connected to the total flue gas outlet;

[0017] It further includes: a regulating valve. The regulating valve is a water flow regulating valve and is arranged on the process water pipeline connected to the two-fluid spray gun;

[0018] It further includes: a transition section. The transition section is an inclined straight cylinder structure, with the higher end connected to the bottom end of the outer cylinder and the lower end connected to the dust removal device.

[0019] A semi-dry flue gas desulfurization system provided by the utility model includes a desulfurization tower arranged in a double sleeve structure. Under the condition of the same reactor cross-sectional size, it can greatly increase the residence time of the flue gas in the reactor, thereby prolonging the sufficient contact time between the desulfurizer and the flue gas and improving the desulfurization reaction efficiency. It is provided with a flue gas inlet section and a Venturi acceleration section, and a deflector is arranged in the flue gas inlet section to ensure that the flue gas can enter the desulfurization tower from bottom to top at a sufficient speed and then fully react. In this solution, a two-fluid spray gun is arranged in front of the desulfurization tower inlet to ensure that the flue gas can be combined with atomized process water before entering the desulfurization tower. The two-fluid spray gun is arranged at the rear end of the Venturi acceleration section to ensure that after the accelerated high-speed flue gas is combined with a large number of droplets, the temperature of the flue gas can be quickly reduced, closer to the adiabatic saturation temperature of the flue gas, which is beneficial to the desulfurization reaction and can improve the reaction efficiency. In the technical solution of this application, the flue gas inlet section, the Venturi acceleration section and the desulfurization tower are arranged from bottom to top, and the deflector and the two-fluid spray gun are arranged in the inner cavity of the equipment. The whole equipment is very compact, occupies a small area, and reduces the overall investment cost of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of the semi-dry flue gas desulfurization system of this application;

[0021] Figure 2 is a schematic front view structural diagram of the deflector;

[0022] Figure 3 is a schematic left view structural diagram of the deflector. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] As Figure 1 shown, this application includes a semi-dry flue gas desulfurization system, which includes: a flue gas inlet section 1, a Venturi acceleration section 2, and a desulfurization tower arranged from bottom to top, as well as a deflector 3, a desulfurizer nozzle 4, and a two-fluid spray gun 5 arranged in the inner cavity of the equipment.

[0024] The desulfurization tower is of a sleeve structure, which includes: an inner cylinder 6 and an outer cylinder 7. The outer cylinder 7 is sleeved outside the inner cylinder 6 from top to bottom. Specifically, when implemented, a vertical partition can be arranged between the outer side wall of the inner cylinder and the inner side wall of the outer cylinder, and the inner cylinder and the outer cylinder are connected at the same time to ensure that both the inner cylinder and the outer cylinder can be connected and a flue gas channel can be formed between the inner cylinder and the outer cylinder.

[0025] The desulfurization tower structure adopts a double sleeve design. Compared with a general desulfurization tower, the double sleeve structure form has a longer flue gas channel, which can make the flue gas stay in the desulfurization tower for a longer time, ensure that the reaction time of the flue gas in the desulfurization tower is more sufficient, absorb more SO 2 harmful substances, so that the SO in the flue gas discharged from the desulfurization tower outlet 2Lower concentration. The desulfurization tower in this application adopts a double-sleeve layout. Under the condition of the same reactor cross-sectional size, it can greatly increase the residence time of the flue gas in the reactor, thereby prolonging the sufficient contact time between the desulfurizer and the flue gas and improving the desulfurization reaction efficiency.

[0026] The top outlet 13 of the flue gas inlet section 1 is connected to the bottom inlet of the Venturi acceleration section 2. The soot outlet 14 is arranged at the bottom end of the flue gas inlet section 1, and the flue gas inlet 12 is arranged on the side wall and connected to the flue gas passage of the incinerator. At the same time, a manhole 11 for maintenance is also arranged on the flue gas inlet section 1.

[0027] The Venturi acceleration section 2 includes a gradually decreasing contraction section with a shorter length arranged from bottom to top, a straight pipe section with the smallest diameter, and a gradually increasing diffusion section. The flue gas enters from the bottom, accelerates in the straight pipe section with the smallest diameter, and then sprays out from the top.

[0028] The top outlet of the Venturi acceleration section 2 is connected to the bottom inlet 61 of the inner cylinder 6. The top outlet 62 of the inner cylinder 6 is connected to the inner cavity of the outer cylinder 7. A flue gas passage is arranged between the inner wall of the outer cylinder 7 and the outer wall of the inner cylinder 6. The bottom end of the outer cylinder 7 is provided with a flue gas total outlet 72 connected to the flue gas dust removal equipment;

[0029] The two-fluid spray gun 5 is arranged in the Venturi acceleration section 2 near the inner cylinder 6; the two-fluid spray gun 5 is connected to the process water supply device;

[0030] The desulfurizer nozzle 4 is arranged below the two-fluid spray gun 5; the desulfurizer nozzle 4 is connected to the desulfurizer supply equipment. In this embodiment, slaked lime is used as the desulfurizer;

[0031] The baffle plate 3 is arranged in the inner cavity of the flue gas inlet section 1, and the adjacent baffle plates form a flue gas inlet channel.

[0032] Based on the equipment in this application, before the flue gas enters the desulfurization tower after acceleration, first inject the desulfurizer into the flue gas based on the desulfurizer nozzle 4, and then form a humidification activation system based on the two-fluid spray gun 5. At the rear end of the Venturi acceleration section of the desulfurization tower, atomize the process water through the two-fluid spray gun and spray it into the desulfurization tower, instantly cooling and humidifying the flue gas. At the same time, greatly improve the chemical reaction activity of the desulfurizer, and improve the desulfurization efficiency in an environment closer to the adiabatic saturated flue gas, and the desulfurization effect is better.

[0033] Such as Figure 2 And Figure 3 As shown, the baffle plate 3 includes: an arc plate 31 and a reinforcing rib 32. The arc plates 31 are of unequal length, and the adjacent arc plates 31 form an arc-shaped flue gas inlet channel. The bottom of the flue gas inlet channel faces the flue gas inlet, and the top faces the bottom inlet of the Venturi acceleration section; the reinforcing rib 32 is arranged on the plate surface of the arc plate 31 facing the flue gas inlet to ensure the stability of the arc plate.

[0034] Figure 1 In the illustrated example, the inner arc of the arc-shaped plate 31 faces the flue gas inlet 12, and its radian is adapted to the angle between the bottom inlet of the flue gas introduction section 1 and the flue gas inlet 12; the reinforcing rib 32 is arranged on the plate surface of the arc-shaped plate 31 on the side facing the flue gas inlet 12; a dust leakage hole 33 is arranged at the bottom of the arc-shaped plate 31, and the dust leakage hole 33 is arranged above the soot outlet 14 of the flue gas introduction section 1.

[0035] In this application, a deflector plate is added at the inlet of the desulfurization tower, so that after the flue gas enters the desulfurization tower horizontally, it can rise evenly into the desulfurization tower. After the flue gas enters the desulfurization tower, the flow rate of the flue gas is rapidly increased through the Venturi acceleration section. The high-speed flue gas and the injected desulfurizing agent are rapidly disturbed and mixed, and the desulfurization agent can quickly absorb SO 2 in the flue gas, so as to achieve the effect of quickly removing SO 2 .

[0036] A dust collecting hopper 8 with a wider top and a narrower bottom is arranged at the bottom of the flue gas introduction section 1. The dust collecting hopper 8 is arranged below the soot outlet 14, and the dust collecting hopper 8 is connected to the ash storage tank 83 through a slide valve 81 and a dust discharging valve 82. Since the flow rate of the flue gas is not high at the inlet of the desulfurization tower, some fly ash in the flue gas will settle. By arranging the dust collecting hopper 8 at the bottom of the desulfurization tower, a certain amount of fly ash can be stored. Through the slide valve 81 and the dust discharging valve 82, the fly ash in the dust collecting hopper 8 is regularly discharged and transported out for unified treatment through the ash storage tank 83, so as to ensure that the long-term operating desulfurization tower is not blocked by fly ash, thereby enabling the system to operate stably.

[0037] In order to ensure production safety, a flue gas inlet pressure detection device 91 and a total flue gas outlet pressure detection device 92 are also provided in this application. The flue gas inlet pressure and the total flue gas outlet pressure are monitored in real time. By calculating the difference between the two, parameters such as the desulfurizing agent injection amount of the system and the process water amount sprayed by the two-fluid spray gun 5 can be adjusted based on the pressure difference to ensure the production safety of the system. At the same time, a regulating valve 95 and a temperature measuring device 94 are also provided. The temperature measuring device 94 is arranged on the flue gas channel communicated with the total flue gas outlet 72; the regulating valve 95 is a water flow regulating valve 95 and is arranged on the process water pipeline connected to the two-fluid spray gun 5.

[0038] During actual application, based on the instrument interlock control technology in the prior art, through online instrument monitoring, the regulating valve 95 can be controlled to adjust the amount of process water sprayed, which not only ensures the desulfurization effect of the desulfurization system, but also can interlock with the temperature measuring device 94 to monitor and control the outlet temperature of the desulfurization tower, that is, the temperature inside the tower, so as to minimize the impact of the desulfurization tower outlet temperature on downstream equipment. In addition, the operation resistance of the system can be monitored online in real time to ensure the stable operation of the equipment.

[0039] In order to reduce the probability of dust entrained in the flue gas blocking the passage, a transition section 71 is provided at the bottom outlet of the outer cylinder 7. The transition section 71 is an inclined straight cylinder structure, with the higher end connected to the bottom end of the outer cylinder 7 and the lower end connected to the dust removal equipment as the flue gas total outlet 72. Based on the transition section 71, the flue gas rushes from the top to the bottom of the outer cylinder 7 from the total flue gas outlet 72 provided at the bottom of the outer cylinder 7 to the bag filter behind, reducing the probability of dust accumulation in the connection section between the two devices.

[0040] Based on the equipment of the present application, the raw flue gas from the incinerator passes through the flue of the flue gas inlet 12 of the desulfurization tower under the action of the induced draft fan, and under the action of the guide plate 3, the raw flue gas rises evenly into the desulfurization tower. The rising raw flue gas acts as an accelerator in the Venturi acceleration section 2, rapidly increasing the flow rate of the flue gas, and quickly disturbing and mixing with the desulfurizer sprayed in by the desulfurizer nozzle 4. After entering the desulfurization tower with a long flue gas channel, the desulfurizer fully contacts the flue gas to produce a chemical reaction, thereby removing SO in the flue gas. 2 In the specific implementation, the dual-fluid spray gun 5 in the humidification activation system atomizes the process water into fine droplets with a particle size of less than 50 microns. A large number of droplets can quickly reduce the flue gas temperature, closer to the adiabatic saturation temperature of the flue gas, which is conducive to the desulfurization reaction. At the same time, the process water can humidify the desulfurizer and increase the activity of the desulfurizer, which can greatly improve the desulfurization efficiency and ensure that the flue gas meets the emission standards.

[0041] After using the technical solution of the utility model, not only can the size of the main desulfurization tower equipment be effectively reduced, but also SO in the flue gas can be removed more efficiently. 2 By adding online monitoring function, the operation resistance and outlet flue gas temperature of the desulfurization tower system can be controlled online, thus enhancing the stability of the system.

Claims

1. A flue gas semi-dry desulfurization system, comprising: The desulfurization tower is characterized in that it also includes: a flue gas inlet section, a venturi acceleration section, a guide plate, a desulfurizer nozzle and a dual-fluid spray gun; The desulfurization tower is a sleeve structure, which includes: an inner cylinder and an outer cylinder, wherein the outer cylinder is sleeved on the outside of the inner cylinder from top to bottom; The top of the smoke introduction section is connected to the bottom inlet of the Venturi acceleration section, the bottom of the smoke introduction section is provided with an ash outlet, and the side wall of the smoke introduction section is provided with a smoke introduction port connected to the smoke channel of the incinerator; The top outlet of the venturi acceleration section is connected to the bottom inlet of the inner cylinder, the top outlet of the inner cylinder is connected to the inner cavity of the outer cylinder, the inner wall of the outer cylinder and the outer wall of the inner cylinder form a flue gas channel, and the bottom end of the outer cylinder is provided with a total flue gas outlet connected to a flue gas dust removal device; The dual-fluid spray gun is arranged in the Venturi acceleration section near the inner cylinder; the dual-fluid spray gun is connected to the process water supply device; The desulfurizer nozzle is arranged in the Venturi acceleration section below the dual-fluid spray gun; the desulfurizer nozzle is connected to the desulfurizer supply equipment; The guide plates are arranged in the inner cavity of the smoke inlet section, and adjacent guide plates form smoke inlet channels.

2. A flue gas semi-dry desulfurization system according to claim 1, characterized in that: The guide plate comprises: an arc-shaped plate and reinforcing ribs; The arc plates are of unequal lengths, and an arc-shaped smoke inlet channel is formed between adjacent arc plates; the bottom of the smoke inlet channel faces the smoke inlet port, and the top faces the bottom entrance of the Venturi acceleration section; the reinforcing ribs are arranged on the plate surface of the arc plate on the side facing the smoke inlet port.

3. A flue gas semi-dry desulfurization system according to claim 2, characterized in that: An ash leakage hole is arranged at the bottom of the arc-shaped plate, and the ash leakage hole is arranged above the ash outlet of the smoke inlet section.

4. The flue gas semi-dry desulfurization system according to claim 1, characterized in that: An ash collecting hopper which is wide at the top and narrow at the bottom is arranged at the bottom of the smoke inlet section. The ash collecting hopper is arranged below the smoke ash outlet and is connected to the ash storage tank.

5. The flue gas semi-dry desulfurization system according to claim 1, characterized in that: It also includes: a pressure difference measuring device and a temperature measuring device, wherein the pressure difference measuring device is arranged between the smoke channel of the smoke inlet and the smoke channel connected to the smoke main outlet; and the temperature measuring device is arranged on the smoke channel connected to the smoke main outlet.

6. The flue gas semi-dry desulfurization system according to claim 1, characterized in that: It also includes: a regulating valve, which is a water regulating valve and is arranged on a process water pipeline connected to the dual-fluid spray gun.

7. The flue gas semi-dry desulfurization system according to claim 1, characterized in that: It also includes: a transition section, which is an inclined straight cylinder structure, with a higher end connected to the bottom end of the outer cylinder and a lower end connected to a dust removal device.

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