Dry deacidification flue gas purification device coupled with filtering dust removal device and control method

Abstract

The present invention discloses a dry deacidification flue gas purification device coupled with a filter-type dust removal device and a control method, and relates to the technical field of flue gas purification. The dry deacidification flue gas purification device comprises a deacidification device and a filter-type dust removal device, the deacidification device is connected to a deacidification agent injection system, the deacidification agent injection system is connected to a deacidification agent grinding system, the filter-type dust removal device is composed of at least two chambers, the inlet of each chamber is provided with a chamber inlet partition valve, the outlet of each chamber is provided with a chamber outlet partition valve, and the inlet of each chamber is connected to a deacidification agent pulse injection partition valve. The present invention can eliminate the problem of excessive emission of acidic gases such as SO2 and HCl caused by the cleaning of the filter-type dust removal device and the fluctuation of the concentration of pollutants in the inlet flue gas, improve the distribution effect of flue gas and deacidification agent between the chambers, improve the average deacidification efficiency, reduce the consumption of deacidification agent, and reduce the operating cost of the flue gas purification system.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas purification, and in particular to a dry deacidification flue gas purification device coupled with a filtering dust removal device and a control method. Background Art

[0002] Dry deacidification is a process that uses dry deacidifiers to react with acidic gases in flue gas and remove acidic gases in flue gas. Commonly used dry deacidifiers in industry can be divided into calcium-based deacidifiers and sodium-based deacidifiers. Calcium-based deacidifiers are mainly CaCO3, Ca(OH)2, CaO, etc., and sodium-based deacidifiers are mainly NaHCO3 (baking soda), Na2CO3, etc. The baking soda dry deacidification technology refers to grinding the raw material NaHCO3 into a powder of 15μm to 25μm through a grinder, spraying it into the deacidification reactor or flue, and after thermal activation in high-temperature flue gas, the specific surface area increases rapidly, fully contacts with the acidic gases in the flue gas, undergoes physical and chemical reactions, and absorbs and purifies acidic substances such as SO2 and HCl in the flue gas, thereby achieving efficient deacidification of the flue gas. In order to improve the effect of baking soda dry deacidification and the utilization rate of baking soda, baking soda dry deacidification is usually coupled with a filter dust removal device. When the filter dust removal device is used to collect dust at the outlet of the baking soda dry deacidification equipment, the unreacted baking soda added by the upstream deacidification equipment is captured by the filter element together with dust and other particulate matter, and evenly distributed on the surface of the filter element. The acid gas in the flue gas and the baking soda enriched on the outer surface of the filter element can continue to undergo deacidification reaction to achieve secondary deacidification, thereby improving the deacidification effect and the utilization rate of the absorbent. In recent years, with increasingly stringent environmental protection requirements, the baking soda dry deacidification technology coupled with filter dust removal has been increasingly used due to its high deacidification efficiency, short process route, compact equipment layout, small site occupancy, low energy consumption, no water consumption in the treatment process, and no wastewater generation.

[0003] Invention patent application CN113262623A discloses a process for the coordinated treatment of multiple pollutants in flue gas from a garbage incinerator. Flue gas at a temperature of 240°C -280°C enters a dry deacidification tower and reacts with fine baking soda powder sprayed into the deacidification tower to achieve primary deacidification. The flue gas after primary deacidification enters an integrated purification reactor through a flue, and a filter unit pre-installed with a catalyst achieves secondary deacidification, heavy metal adsorption removal, dust removal, denitrification and dioxin decomposition coordinated treatment. In this technology, baking soda is used as a deacidification agent and is added entirely from the entrance of the dry deacidification tower.

[0004] The inventors found during the research that this technology has the following problems in actual use:

[0005] (1) After the filter dust removal device has been running for a period of time, the filter element needs to be cleaned to remove the baking soda, fly ash, deacidification products, etc. accumulated on the surface of the filter element, causing the secondary deacidification effect to drop sharply, thereby causing the emission of acidic gases such as SO2 and HCl to exceed the standard;

[0006] (2) Usually, the injection amount of baking soda is automatically controlled by PID using the HCl concentration and SO2 concentration monitored by the chimney outlet CEMS and the set HCl control concentration target value and SO2 control concentration target value. This control method is feedback regulation. When the HCl and SO2 concentrations in the inlet flue gas fluctuate greatly, it is easy to cause the emission of acidic gases such as SO2 and HCl to exceed the standard;

[0007] (3) Since the particle size of baking soda used is usually between 15μm and 25μm, and baking soda will also undergo thermal fragmentation in hot flue gas, further reducing the particle size, when the filter element is a ceramic filter tube, fine particles can easily block the internal pores of the ceramic filter cartridge, causing increased resistance and incomplete cleaning, which will reduce the service life of the ceramic filter cartridge in the long run;

[0008] (4) Since the injection point of the deacidifying agent is located at the entrance of the dry deacidifying tower or the main entrance of the filter-type dust removal device, the chamber cannot be sprayed separately. When a chamber is cleaned and put into operation again, the resistance of this chamber is lower than that of other chambers that have not been cleaned, resulting in uneven distribution of flue gas flow and deacidifying agent between the chambers of the filter-type dust removal device, resulting in more deacidifying agent consumption. Summary of the invention

[0009] In view of this, an embodiment of the present invention provides a dry deacidification flue gas purification device and a control method coupled with a filtering dust removal device to solve the problems existing in the above-mentioned prior art.

[0010] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0011] In one aspect, the present invention provides a dry deacidification flue gas purification device coupled with a filter-type dust removal device, comprising a deacidification device and a filter-type dust removal device connected in sequence, wherein:

[0012] The deacidification device is connected to a deacidification agent injection system, the deacidification agent injection system is connected to a deacidification agent grinding system, and the deacidification agent is a calcium-based deacidification agent, a sodium-based deacidification agent, or a mixture of a sodium-based deacidification agent and a calcium-based deacidification agent;

[0013] The filtering dust removal device refers to a device with a porous filter element installed inside and having a dust removal function, wherein the porous filter element is a cloth bag, a ceramic filter tube or a metal filter bag; the filtering dust removal device is composed of at least two chambers, the inlet of each chamber is provided with a chamber inlet isolation valve, the outlet of each chamber is provided with a chamber outlet isolation valve, and the inlet of each chamber is connected to a deacidifying agent pulse jet isolation valve; the total inlet of the filtering dust removal device is provided with an inlet pressure transmitter, and the total outlet is provided with an outlet pressure transmitter and an outlet CEMS.

[0014] Furthermore, the deacidifying agent grinding system comprises a deacidifying agent coarse powder bin, a coarse powder bin metering feeding device, a deacidifying agent grinder and a grinder powder conveying fan which are connected in sequence, and the outlet of the grinder powder conveying fan is provided with a first pipeline and a second pipeline;

[0015] The deacidifying agent injection system includes a deacidifying agent fine powder bin, a deacidifying agent metering and weighing device, a deacidifying agent powder conveying fan, a deacidifying agent powder conveying injector and a deacidifying agent fine powder bin inlet isolation valve. The first pipeline is connected to the deacidifying agent fine powder bin via the deacidifying agent fine powder bin inlet isolation valve, and the second pipeline is connected to each chamber via the deacidifying agent pulse injection isolation valve.

[0016] Furthermore, the deacidifying agent grinding machine is an air classifying mill, which has a remote adjustment function, and frequency conversion is used to adjust the running speed of the classifying wheel built into the deacidifying agent grinding machine to control the particle size of the deacidifying agent at the grinding machine outlet;

[0017] And / or, the coarse powder bin metering feeding device is a metering rotary feeding valve with a remote adjustment function, and adopts frequency conversion to adjust the motor speed of the rotary feeding valve to control the flow of the deacidifying agent entering the deacidifying agent grinder;

[0018] And / or, the deacidifying agent metering and weighing device adopts a loss-in-weight scale with a remote adjustment function to control the amount of deacidifying agent injected into the deacidifying device as required.

[0019] Furthermore, the deacidification device is a dry deacidification tower, or the dry deacidification tower can be eliminated and replaced by a deacidification flue;

[0020] And / or, the porous filter element is a catalytic filter element, a catalyst is loaded in the porous filter element, and the catalyst is one or more combinations of an SCR denitration catalyst, a dioxin catalytic oxidation catalyst, and a VOCs catalytic oxidation catalyst.

[0021] Furthermore, the catalytic filter element is an SCR catalytic filter bag or an SCR catalytic ceramic filter cartridge, and the inlet of the filter-type dust removal device is connected to an SCR reducing agent preparation system to provide the reducing agent required for the SCR reaction;

[0022] And / or, the SCR reducing agent is ammonia water, and the SCR reducing agent preparation system includes an ammonia water storage tank, an ammonia water delivery pump and an ammonia water atomizing spray gun connected in sequence, and the ammonia water in the ammonia water storage tank is delivered to the flue at the inlet of the filtering dust removal device by the ammonia water delivery pump and the ammonia water atomizing spray gun.

[0023] On the other hand, the present invention provides a control method for the dry deacidification flue gas purification device coupled with the above-mentioned filtering dust removal device, comprising:

[0024] Step 1: Set the initial chamber and cleaning start differential pressure Crit_DP for the filter dust removal device to perform the cleaning procedure, and proceed to step 2;

[0025] Step 2: Start the deacidification agent continuous injection program, and then proceed to step 3;

[0026] Step 3: Determine whether the measured value PV_DP of the operating differential pressure of the filter dust removal device is greater than or equal to the set cleaning start differential pressure Crit_DP. When the judgment result is "yes", execute step 4; when the judgment result is "no", execute step 8;

[0027] Step 4: Start the chamber cleaning program. After the chamber cleaning program is completed, proceed to step 5;

[0028] Step 5: Start the deacidification agent pulse injection program, and then proceed to step 6;

[0029] Step 6: Determine whether all chambers of the filter dust removal device have been cleaned. If all chambers have been cleaned, execute step 8; otherwise, execute step 7.

[0030] Step 7: Specify the subsequent chambers for the cleaning procedure, and then proceed to step 4;

[0031] Step 8: Determine whether to end the automatic control. When the judgment result is "yes", end the automatic control. When the judgment result is "no", execute step 3.

[0032] Furthermore, in step 2, the deacidification agent continuous injection procedure includes:

[0033] A1: Set the control target value SV_HCl of HCl and the control target value SV_SO2 of SO2 at the outlet of the flue gas purification device;

[0034] A2: The concentration value of HCl PV_HCl and the concentration value of SO2 PV_SO2 at the outlet of the flue gas purification device are measured by the outlet CEMS;

[0035] A3: According to the difference between the set acid gas control target value and the acid gas concentration value measured by the outlet CEMS, namely (PV_HCl-SV_HCl) and (PV_SO2-SV_SO2), the mass flow rate of the continuous injection of the deacidifying agent is adjusted through PID;

[0036] And / or, in step 4, the bin cleaning procedure includes:

[0037] B1: Close the compartment outlet isolation valve;

[0038] B2: Clean the filter elements in the chamber by using line-jet pulse cleaning, rotary pulse cleaning or box-type pulse cleaning;

[0039] And / or, in step 7, the selection of subsequent chambers must ensure that all chambers of the filtering dust removal device can be cleaned in a complete cleaning cycle, and each chamber is cleaned only once.

[0040] Furthermore, in step 5, the deacidification agent pulse injection procedure includes:

[0041] C1: Close the compartment inlet isolation valve;

[0042] C2: Open the deacidification agent pulse jet isolation valve and close the deacidification agent fine powder bin inlet isolation valve;

[0043] C3: Open the compartment outlet isolation valve;

[0044] C4: Start the powder conveying fan of the grinding machine;

[0045] C5: Start the deacidifying agent grinder;

[0046] C6: Adjust the operating parameters of the deacidifying agent grinder so that the particle size of the deacidifying agent at the grinder outlet is within the specified range;

[0047] C7: Start the metering feeding device of the coarse powder bin and measure the total amount of deacidifying agent PV_F_Pulse entering the bin through the pulse injection of deacidifying agent;

[0048] C8: When PV_F_Pulse is greater than the set value SV_F_Pulse, the coarse powder bin metering feeding device is stopped;

[0049] C9: Stop the deacidifier grinder;

[0050] C10: Stop the powder conveying fan of the deacidifying agent grinding machine;

[0051] C11: Close the deacidification agent pulse jet isolation valve;

[0052] C12: Open the chamber inlet isolation valve.

[0053] Furthermore, in step 1, the dust cleaning start differential pressure Crit_DP=1000~2500Pa;

[0054] And / or, in step 5, the particle size range of the deacidifying agent at the outlet of the grinder is 5 μm to 90 μm, when the absorbent is baking soda, the particle size range is 15 μm to 25 μm, and the setting value SV_F_Pulse of the total amount of pulse injection of the deacidifying agent is in kg;

[0055] Where: SV_F_Pulse=Si×F_sorbent×T_cyc÷n_cab

[0056] Wherein, Si is the pulse injection coefficient, that is, the ratio of the pulse injection deacidification dosage to the deacidification dosage required for deacidification, Si=0~1; F_sorbent is the mass flow rate of the deacidification agent required for deacidification, in kg / h, using the multi-year statistical average value of the project or the theoretical calculated value; T_cyc is the cleaning interval of the filter-type dust removal device, in h; n_cab is the total number of chambers of the filter-type dust removal device.

[0057] Further, when the deacidifying agent is baking soda and the filter element is a ceramic filter tube, the particle size of the deacidifying agent at the outlet of the grinder in step 5 is variably adjusted. At the beginning of the deacidifying agent pulse injection, the operating parameters of the deacidifying agent grinder are adjusted to control the particle size of the deacidifying agent at the outlet of the grinder to be 70 μm-90 μm, and a layer of deacidifying agent powder with a larger particle size is formed on the surface of the filter element, which is conducive to more thorough dust cleaning, and the injection amount is SV_F_Pulse_1; then the operating parameters of the deacidifying agent grinder are adjusted again to control the particle size of the deacidifying agent at the outlet of the grinder to be 15 μm-25 μm, and the injection amount is SV_F_Pulse_2, which is equal to the difference between SV_F_Pulse and SV_F_Pulse_1;

[0058] Where: SV_F_Pulse_1=K×A_Fil_Ele×n_Fil_Ele, unit is kg;

[0059] Where K is the coating spray coefficient, unit is kg / m 2 , K = 0.03 ~ 0.3; A_Fil_Ele is the filtration area of ​​a single filter element, in m 2 ; n_Fil_Ele is the number of filter elements installed in a single chamber.

[0060] The present invention has the following beneficial effects:

[0061] 1. The dry deacidification flue gas purification device and control method of the coupled filtering dust removal device provided by the present invention, the filtering dust removal device is composed of at least two chambers, the chambers are cleaned by offline cleaning, after each chamber is offline cleaned, the porous filter element in the chamber is sprayed with a deacidifying agent pulse jet, and a deacidifying agent powder layer is formed on the surface of the porous filter element in a short time, thereby reducing the influence of the cleaning of the filtering dust removal device on the secondary deacidification effect, and eliminating the problem of excessive emission of acidic gases such as SO2 and HCl caused by the cleaning of the filtering dust removal device.

[0062] 2. Since the porous filter element in the chamber is sprayed with a deacidifying agent pulse jet after the filter-type dust removal device is cleaned, a deacidifying agent powder layer is formed on the surface of the filter element in advance, which can reduce the excessive emission caused by the large fluctuation of HCl and SO2 concentrations in the inlet flue gas of the dry deacidifying flue gas purification device.

[0063] 3. When the deacidifying agent is baking soda and the filter element is a ceramic filter tube, the particle size of the deacidifying agent pulse jet is increased at the beginning of the deacidifying agent pulse jet, and a layer of large-particle deacidifying agent layer is formed on the surface of the filter element, which reduces the probability of fine particles entering the internal pores of the ceramic filter cartridge, increases the service life of the ceramic filter cartridge, reduces the resistance of the flue gas purification system, and reduces the operating cost of the flue gas purification system.

[0064] 4. Through the coordination of pulse injection of deacidifying agent and continuous injection of deacidifying agent, the uniformity of resistance between chambers after cleaning can be improved, the distribution effect of flue gas and deacidifying agent between chambers can be improved, the average deacidification efficiency of dry deacidifying flue gas purification device can be improved, the consumption of deacidifying agent can be reduced, and the operating cost of flue gas purification system can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0066] Figure 1 It is a process flow chart of the first embodiment of the dry deacidification flue gas purification device coupled with the filter-type dust removal device of the present invention;

[0067] Figure 2 It is a process flow chart of the second embodiment of the dry deacidification flue gas purification device coupled with the filter-type dust removal device of the present invention;

[0068] Figure 3 It is a logic diagram of the dry deacidification flue gas purification control method of the coupled filtering dust removal device of the present invention.

[0069] In the figure: 1-dry deacidification tower, 2-filter dust removal device, 201~204-chamber of filter dust removal device, 211~214-chamber inlet isolation valve, 221~224-chamber outlet isolation valve, 231-inlet pressure transmitter, 232-outlet pressure transmitter, 3-external economizer, 4-fan, 5-chimney, 6-baking soda coarse powder silo, 7-coarse powder silo metering feeding device, 8-deacidifying agent grinder, 9-grinder powder conveying fan, 10-(grinding 1-(mill powder conveying fan outlet) first pipeline, 11-deacidifier fine powder bin inlet isolation valve, 12-deacidifier fine powder bin, 13-deacidifier metering and weighing device, 14-deacidifier powder conveying fan, 15-deacidifier powder conveying injector, 16-(grinder powder conveying fan outlet) second pipeline, 17-deacidifier pulse injection isolation valve, 18-ammonia storage tank, 19-ammonia delivery pump, 20-ammonia atomizing spray gun, 21-export CEMS, 22-inlet CEMS, 23-incinerator. DETAILED DESCRIPTION

[0070] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0071] It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0072] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. Embodiment 1:

[0073] The basic design parameters of this embodiment are shown in Table 1 below:

[0074] Table 1

[0075] Serial number project unit Numeric 1 Flue gas flow to be deacidified <![CDATA[Nm 3 / h]]> 35,000.00 2 Flue gas components to be deacidified 3 <![CDATA[H2O]]> % 20.97% 4 <![CDATA[O2]]> % 7.00% 5 <![CDATA[N2]]> % 63.11% 6 <![CDATA[CO2]]> % 8.06% 7 Flue gas pollutant concentration to be deacidified 8 <![CDATA[SO2]]> <![CDATA[mg / Nm 3 ]]> 500.00 9 HCl <![CDATA[mg / Nm 3 ]]> 800.00 10 Dust concentration <![CDATA[mg / Nm 3 ]]> 4,000.00 11 Flue gas temperature to be deacidified ℃ 180.00 12 Pollutant concentration control target value 13 <![CDATA[SO2]]> <![CDATA[mg / Nm 3 ]]> 30.00 14 HCl <![CDATA[mg / Nm 3 ]]> 10.00 15 Baking soda mass consumption (calculated value) kg / h 124.38 16 Number of chambers of filter dust removal device indivual 4 17 Number of filter elements in a single compartment indivual 252 18 Filter area of ​​a single filter element <![CDATA[m 2 ]]> 1.32

[0076] The dry deacidification flue gas purification device coupled with the filter dust removal device of this embodiment is as follows: Figure 1 As shown, the flue gas to be deacidified enters the dry deacidification flue gas purification device from the inlet of the deacidification device (i.e., the dry deacidification tower 1), and the dry deacidification flue gas purification device includes a deacidification device 1 and a filtering dust removal device 2 which are connected in sequence (specifically, they can be connected through a flue), wherein:

[0077] The dry deacidification tower 1 is connected to a deacidification agent injection system, and the deacidification agent injection system is connected to a deacidification agent grinding system, and the deacidification agent is baking soda (NaHCO3);

[0078] The filtering dust removal device 2 refers to a device with a porous filter element installed inside and having a dust removal function, and the porous filter element is a cloth bag; the filtering dust removal device 2 is composed of four chambers 201, 202, 203, and 204, and the inlet of each chamber is provided with a chamber inlet isolation valve 211, 212, 213, and 214, and the outlet of each chamber is provided with a chamber outlet isolation valve 221, 222, 223, and 224, and the inlet of each chamber is connected to a deacidifying agent pulse jet isolation valve 17; the total inlet of the filtering dust removal device 2 is provided with an inlet pressure transmitter 231, and the total outlet is provided with an outlet pressure transmitter 232 and an outlet CEMS21, and the deacidified flue gas is drawn out from the flue gas outlet of the filtering dust removal device 2.

[0079] Preferably, the deacidifying agent grinding system may include a deacidifying agent coarse powder bin 6, a coarse powder bin metering feeding device 7, a deacidifying agent grinder 8 and a grinder powder conveying fan 9 connected in sequence, and the outlet of the grinder powder conveying fan 9 is provided with a first pipeline 10 and a second pipeline 16.

[0080] Preferably, the deacidifying agent injection system may include a deacidifying agent fine powder bin 12, a deacidifying agent metering and weighing device 13, a deacidifying agent powder conveying fan 14, a deacidifying agent powder conveying injector 15 and a deacidifying agent fine powder bin inlet isolation valve 11. The first pipeline 10 is connected to the deacidifying agent fine powder bin 12 via the deacidifying agent fine powder bin inlet isolation valve 11, and the second pipeline 16 is connected to each chamber 201, 202, 203, and 204 via the deacidifying agent pulse injection isolation valve 17.

[0081] Preferably, the deacidifying agent grinder 8 can be an air classifying mill with a remote adjustment function. By frequency conversion adjusting the running speed of the classifying wheel built into the deacidifying agent grinder 8, the particle size of the deacidifying agent at the outlet of the grinder can be controlled; the coarse powder bin metering feeding device 7 can be a metering rotary feeding valve with a remote adjustment function. By frequency conversion adjusting the motor speed of the rotary feeding valve, the flow of the deacidifying agent entering the deacidifying agent grinder can be controlled; the deacidifying agent metering weighing device 13 can be a loss-in-weight scale with a remote adjustment function, which can control the amount of deacidifying agent injected into the deacidifying device 1 as needed.

[0082] Based on the dry deacidification flue gas purification device coupled with the filter-type dust removal device, this embodiment also provides a dry deacidification flue gas purification control method coupled with the filter-type dust removal device. Figure 3 As shown, the following steps are included:

[0083] When the dry deacidification flue gas purification device is put into operation, it is controlled according to the following procedures:

[0084] Step 1: Set the initial chamber and the cleaning start differential pressure Crit_DP for the filter dust removal device 2 to perform the cleaning procedure, and then execute step 2;

[0085] In this step, the initial chamber can be any one of all the chambers of the filtering dust removal device 2, and the cleaning starting differential pressure Crit_DP=1000~2500Pa, preferably, Crit_DP=1500~1800Pa.

[0086] In this embodiment, the initial cleaning chamber is 201, and the cleaning starting differential pressure Crit_DP=1500Pa.

[0087] Step 2: Start the deacidification agent continuous injection program, and then proceed to step 3;

[0088] As an optional embodiment, in step 2, the deacidification agent continuous injection procedure includes:

[0089] A1: Set the control target value SV_HCl of HCl and the control target value SV_SO2 of SO2 at the outlet of the flue gas purification device;

[0090] In this embodiment, SV_HCl=10mg / Nm 3 (Standard state, dry basis, standard oxygen content), SV_SO2=30mg / Nm 3 (Standard state, dry basis, standard oxygen content).

[0091] A2: The outlet HCl concentration value PV_HCl (standard state, dry basis, standard oxygen content) and SO2 concentration value PV_SO2 (standard state, dry basis, standard oxygen content) at the flue gas purification device are measured by the outlet CEMS 21;

[0092] A3: According to the difference between the set acid gas control target value and the acid gas concentration value measured by the outlet CEMS, i.e. (PV_HCl-SV_HCl) and (PV_SO2-SV_SO2), the mass flow rate of the continuous injection of the deacidifying agent is adjusted through PID, i.e., the output of the deacidifying agent metering and weighing device 13 is controlled according to the PID calculation result to adjust the amount of the deacidifying agent added;

[0093] In specific implementation, when the filtering dust removal device 2 is not clearing dust, all the deacidifying agent required for deacidification is provided by the deacidifying agent powder feeding injector 15; when the deacidifying agent fine powder bin 12 needs to be fed, all the deacidifying agent pulse injection isolation valves 17 are closed, the deacidifying agent fine powder bin inlet isolation valve 11 is opened, and the grinder powder feeding fan 9, the deacidifying agent grinder 8, and the coarse powder bin metering feeding device 7 are started in sequence, and the deacidifying agent particle size at the grinder outlet is controlled to be 15μm~25μm, and the feeding of the deacidifying agent fine powder bin 12 is completed. The baking soda particle size in the deacidifying agent coarse powder bin 6 is about 250μm.

[0094] Step 3: Determine whether the measured value PV_DP of the operating differential pressure of the filter dust removal device 2 is greater than or equal to the set dust cleaning start differential pressure Crit_DP (1500Pa in this embodiment). When the judgment result is "yes", execute step 4; when the judgment result is "no", execute step 8;

[0095] In this step, the operating differential pressure PV_DP of the filtering dust removal device 2 can be calculated and obtained through the pressure values ​​measured by the inlet pressure transmitter 231 and the outlet pressure transmitter 232.

[0096] Step 4: Start the chamber cleaning program. After the chamber cleaning program is completed, proceed to step 5;

[0097] As an optional embodiment, in step 4, the bin cleaning procedure includes:

[0098] B1: Close the isolation valve 221 at the outlet of the chamber 201;

[0099] B2: Clean the filter elements in the chamber 201 , and clean all the filter elements in the chamber 201 row by row using a row-jet pulse cleaning method until all the filter elements are cleaned.

[0100] Step 5: Start the deacidification agent pulse injection program, and then proceed to step 6;

[0101] As an optional embodiment, in step 5, the deacidification agent pulse injection procedure includes:

[0102] C1: Close the chamber inlet isolation valve 211;

[0103] C2: Open the deacidifying agent pulse jet isolation valve 17 corresponding to the chamber 201, and close the deacidifying agent fine powder bin inlet isolation valve 11;

[0104] C3: Open the chamber outlet isolation valve 221;

[0105] C4: Start the powder conveying fan 9 of the grinding machine;

[0106] C5: Start the deacidifying agent grinder 8;

[0107] C6: adjusting the operating parameters of the deacidifying agent grinder 8 so that the particle size of the deacidifying agent at the grinder outlet is within a specified range;

[0108] C7: Start the coarse powder bin metering feeding device 7, and measure the total amount of deacidifying agent PV_F_Pulse injected into the bin 201 by the deacidifying agent pulse;

[0109] C8: When PV_F_Pulse is greater than the set value SV_F_Pulse, the coarse powder bin metering feeding device 7 is stopped;

[0110] C9: stop the deacidifying agent grinder 8;

[0111] C10: Stop the powder conveying fan 9 of the deacidifying agent grinding machine;

[0112] C11: close the deacidification agent pulse injection isolation valve 17 corresponding to the chamber 201;

[0113] C12: Open the chamber inlet isolation valve 211 and put the chamber 201 back into use.

[0114] In this step, the deacidifying agent required for the pulse injection of the deacidifying agent can be completely provided by the powder feeding fan 9 of the grinder, and the flow rate and particle size of the pulse injected deacidifying agent can be independently adjusted. In this embodiment, the particle size of the deacidifying agent at the outlet of the deacidifying agent grinder is controlled to be 15μm~25μm during the pulse injection of the deacidifying agent, forming two independent control loops with the continuous injection program of the deacidifying agent.

[0115] In this embodiment, the set value of the total amount of deacidification agent pulse injection SV_F_Pulse (kg);

[0116] Where: SV_F_Pulse=Si×F_sorbent×T_cyc÷n_cab=15.5kg

[0117] Wherein, Si is the pulse injection coefficient, that is, the ratio of the pulse injection deacidification dosage to the deacidification dosage required for deacidification, Si=0.5; F_sorbent is the mass flow rate of the deacidification agent required for deacidification, F_sorbent=124.38kg / h, using the theoretical calculated value; T_cyc is the cleaning interval of the filter dust removal device, T_cyc=1h; n_cab is the total number of chambers of the filter dust removal device, n_cab=4.

[0118] Step 6: Determine whether all chambers of the filter dust removal device 2 have been cleaned. If all chambers have been cleaned, execute step 8; otherwise, execute step 7.

[0119] Step 7: Specify the subsequent chambers for the cleaning procedure, and then proceed to step 4;

[0120] In this embodiment, the principle of designating subsequent chambers may be to perform the dust cleaning procedure in the order of the chambers 201 , 202 , 203 , and 204 .

[0121] As an optional embodiment, in step 7, the selection of subsequent chambers must ensure that all chambers of the filtering dust removal device can be cleaned in a complete cleaning cycle, and each chamber is cleaned only once.

[0122] Step 8: Determine whether to end the automatic control. When the judgment result is "yes", end the automatic control. When the judgment result is "no", execute step 3. Embodiment 2:

[0123] The basic design parameters of this embodiment are shown in Table 2 below:

[0124] Table 2

[0125] Serial number project unit Numeric 1 Flue gas flow to be deacidified <![CDATA[Nm 3 / h]]> 35,000.00 2 Flue gas components to be deacidified 3 <![CDATA[H2O]]> % 20.97% 4 <![CDATA[O2]]> % 7.00% 5 <![CDATA[N2]]> % 63.11% 6 <![CDATA[CO2]]> % 8.06% 7 Flue gas pollutant concentration to be deacidified 8 <![CDATA[SO2]]> <![CDATA[mg / Nm 3 ]]> 500.00 9 HCl <![CDATA[mg / Nm 3 ]]> 800.00 10 <![CDATA[NO x ]]> <![CDATA[mg / Nm 3 ]]> 200 11 Dust concentration <![CDATA[mg / Nm 3 ]]> 4,000.00 12 Flue gas temperature to be deacidified ℃ 240.00 13 Pollutant concentration control target value 14 <![CDATA[SO2]]> <![CDATA[mg / Nm 3 ]]> 30.00 15 HCl <![CDATA[mg / Nm 3 ]]> 10.00 16 <![CDATA[NO x ]]> <![CDATA[mg / Nm 3 ]]> 80 17 Baking soda mass consumption (calculated value) kg / h 124.38 18 Number of chambers of filter dust removal device indivual 4 19 Number of filter elements in a single compartment indivual 288 18 Filter area of ​​a single filter element <![CDATA[m 2 ]]> 1.32

[0126] The dry deacidification flue gas purification device coupled with the filter dust removal device of this embodiment is as follows: Figure 2 As shown, the flue gas to be purified at the outlet of the incinerator 23 enters the dry deacidification flue gas purification device from the inlet of the deacidification device (i.e., the dry deacidification tower 1), and the dry deacidification flue gas purification device includes a dry deacidification tower 1, a filtering dust removal device 2, an external economizer 3, a fan 4 and a chimney 5 connected in sequence through a flue, wherein:

[0127] The dry deacidification tower 1 is connected with a deacidification agent injection system and an inlet CEMS 22, the deacidification agent injection system is connected with a deacidification agent grinding system, and the deacidification agent is baking soda (NaHCO3);

[0128] The filter-type dust removal device 2 refers to a device with a porous filter element installed inside and having a dust removal function. The porous filter element is a ceramic filter cartridge loaded with an SCR catalyst; the filter-type dust removal device 2 is composed of four chambers 201, 202, 203, and 204. The entrance of each chamber is provided with a chamber entrance isolation valve 211, 212, 213, and 214, and the outlet of each chamber is provided with a chamber outlet isolation valve 221, 222, 223, and 224. The entrance of each chamber is connected to a deacidification Agent pulse injection isolation valve 17; the inlet of the filtering dust removal device 2 is connected to the SCR reducing agent preparation system to provide the reducing agent required for the SCR reaction; the total inlet of the filtering dust removal device 2 is provided with an inlet pressure transmitter 231, and the total outlet is provided with an outlet pressure transmitter 232; the purified flue gas is led out from the flue gas outlet of the filtering dust removal device 2, enters the external economizer 3 to recover heat, and is finally discharged into the chimney 5 through the induced draft fan 4, and an outlet CEMS 21 is provided at the inlet flue of the chimney 5.

[0129] Preferably, the deacidifying agent grinding system may include a deacidifying agent coarse powder bin 6, a coarse powder bin metering feeding device 7, a deacidifying agent grinder 8 and a grinder powder conveying fan 9 connected in sequence, and the outlet of the grinder powder conveying fan 9 is provided with a first pipeline 10 and a second pipeline 16.

[0130] Preferably, the deacidifying agent injection system may include a deacidifying agent fine powder bin 12, a deacidifying agent metering and weighing device 13, a deacidifying agent powder conveying fan 14, a deacidifying agent powder conveying injector 15 and a deacidifying agent fine powder bin inlet isolation valve 11. The first pipeline 10 is connected to the deacidifying agent fine powder bin 12 via the deacidifying agent fine powder bin inlet isolation valve 11, and the second pipeline 16 is connected to each chamber 201, 202, 203, and 204 via the deacidifying agent pulse injection isolation valve 17.

[0131] Preferably, the deacidifying agent grinder 8 can be an air classifying mill with a remote adjustment function. By frequency conversion adjusting the running speed of the classifying wheel built into the deacidifying agent grinder 8, the particle size of the deacidifying agent at the outlet of the grinder can be controlled; the coarse powder bin metering feeding device 7 can be a metering rotary feeding valve with a remote adjustment function. By frequency conversion adjusting the motor speed of the rotary feeding valve, the flow of the deacidifying agent entering the deacidifying agent grinder can be controlled; the deacidifying agent metering weighing device 13 can be a loss-in-weight scale with a remote adjustment function, which can control the amount of deacidifying agent injected into the deacidifying device 1 as needed.

[0132] Preferably, the SCR reducing agent is ammonia water, and the SCR reducing agent preparation system includes an ammonia water storage tank 18, an ammonia water delivery pump 19 and an ammonia water atomizing spray gun 20 which are connected in sequence. The ammonia water in the ammonia water storage tank 18 is delivered to the flue at the inlet of the filtering dust removal device 2 by the ammonia water delivery pump 19 and the ammonia water atomizing spray gun 20, and the heat of the flue gas is used to evaporate the ammonia water into ammonia gas, which serves as the reducing agent required for the SCR reaction.

[0133] Based on the dry deacidification flue gas purification device coupled with the filter-type dust removal device, this embodiment also provides a dry deacidification flue gas purification control method coupled with the filter-type dust removal device. Figure 3 As shown, the following steps are included:

[0134] When the dry deacidification flue gas purification device is put into operation, it is controlled according to the following procedures:

[0135] Step 1: Set the initial chamber and the cleaning start differential pressure Crit_DP for the filter dust removal device 2 to perform the cleaning procedure, and then execute step 2;

[0136] In this step, the initial chamber can be any one of all the chambers of the filtering dust removal device 2, and the cleaning starting differential pressure Crit_DP=1000~2500Pa, preferably, Crit_DP=1500~1800Pa.

[0137] In this embodiment, the initial cleaning chamber is 201, and the cleaning starting differential pressure Crit_DP=1500Pa.

[0138] Step 2: Start the deacidification agent continuous injection program, and then proceed to step 3;

[0139] As an optional embodiment, in step 2, the deacidification agent continuous injection procedure includes:

[0140] A1: Set the control target value SV_HCl of HCl and the control target value SV_SO2 of SO2 at the outlet of the flue gas purification device;

[0141] In this embodiment, SV_HCl=10mg / Nm 3 (Standard state, dry basis, standard oxygen content), SV_SO2=30mg / Nm 3 (Standard state, dry basis, standard oxygen content).

[0142] A2: The outlet HCl concentration value PV_HCl (standard state, dry basis, standard oxygen content) and SO2 concentration value PV_SO2 (standard state, dry basis, standard oxygen content) at the flue gas purification device are measured by the outlet CEMS 21;

[0143] A3: According to the difference between the set acid gas control target value and the acid gas concentration value measured by the outlet CEMS, i.e. (PV_HCl-SV_HCl) and (PV_SO2-SV_SO2), the mass flow rate of the continuous injection of the deacidifying agent is adjusted through PID, i.e., the output of the deacidifying agent metering and weighing device 13 is controlled according to the PID calculation result to adjust the amount of the deacidifying agent added;

[0144] In specific implementation, when the filtering dust removal device 2 is not cleaning, all the deacidifying agent required for deacidification is provided by the deacidifying agent powder feeding injector 15; when the deacidifying agent fine powder bin 12 needs to be fed, all the deacidifying agent pulse injection shut-off valves 17 are closed, the deacidifying agent fine powder bin inlet shut-off valve 11 is opened, the grinder powder feeding fan 9, the deacidifying agent grinder 8, and the coarse powder bin metering feeding device 7 are started in sequence, and the deacidifying agent particle size at the grinder outlet is controlled to be 15μm~25μm, and the feeding of the deacidifying agent fine powder bin 12 is completed. The baking soda particle size in the deacidifying agent coarse powder bin 6 is about 250μm.

[0145] Step 3: Determine whether the measured value PV_DP of the operating differential pressure of the filter dust removal device 2 is greater than or equal to the set dust cleaning start differential pressure Crit_DP (1500Pa in this embodiment). If the judgment result is "yes", execute step 4; if the judgment result is "no", execute step 8;

[0146] In this step, the operating differential pressure PV_DP of the filtering dust removal device 2 can be calculated and obtained through the pressure values ​​measured by the inlet pressure transmitter 231 and the outlet pressure transmitter 232.

[0147] Step 4: Start the chamber cleaning program. After the chamber cleaning program is completed, proceed to step 5;

[0148] As an optional embodiment, in step 4, the bin cleaning procedure includes:

[0149] B1: Close the isolation valve 221 at the outlet of the chamber 201;

[0150] B2: Clean the filter elements in the chamber 201 , and clean all the filter elements in the chamber 201 row by row using a row-jet pulse cleaning method until all the filter elements are cleaned.

[0151] Step 5: Start the deacidification agent pulse injection program, and then proceed to step 6;

[0152] As an optional embodiment, in step 5, the deacidification agent pulse injection procedure includes:

[0153] C1: Close the chamber inlet isolation valve 211;

[0154] C2: Open the deacidifying agent pulse jet isolation valve 17 corresponding to the chamber 201, and close the deacidifying agent fine powder bin inlet isolation valve 11;

[0155] C3: Open the chamber outlet isolation valve 221;

[0156] C4: Start the powder conveying fan 9 of the grinding machine;

[0157] C5: Start the deacidifying agent grinder 8;

[0158] C6: adjusting the operating parameters of the deacidifying agent grinder 8 so that the particle size of the deacidifying agent at the grinder outlet is within a specified range;

[0159] C7: Start the coarse powder bin metering feeding device 7, and measure the total amount of deacidifying agent PV_F_Pulse injected into the bin 201 by the deacidifying agent pulse;

[0160] C8: When PV_F_Pulse is greater than the set value SV_F_Pulse, the coarse powder bin metering feeding device 7 is stopped;

[0161] C9: stop the deacidifying agent grinder 8;

[0162] C10: Stop the powder conveying fan 9 of the deacidifying agent grinding machine;

[0163] C11: close the deacidification agent pulse injection isolation valve 17 corresponding to the chamber 201;

[0164] C12: Open the chamber inlet isolation valve 211 and put the chamber 201 back into use.

[0165] In this step, the deacidifying agent required for the pulse injection of the deacidifying agent can be provided entirely by the powder feeding fan 9 of the grinder, and the flow rate and particle size of the pulse injected deacidifying agent can be independently adjusted. In this embodiment, the particle size of the deacidifying agent at the outlet of the deacidifying agent grinder is controlled to be 15~25μm during the pulse injection of the deacidifying agent, forming two independent control loops with the deacidifying agent continuous injection program.

[0166] In this embodiment, the set value of the total amount of deacidification agent pulse injection SV_F_Pulse (kg);

[0167] Where: SV_F_Pulse=Si×F_sorbent×T_cyc÷n_cab=15.5kg

[0168] Wherein, Si is the pulse injection coefficient, that is, the ratio of the pulse injection deacidification dosage to the deacidification dosage required for deacidification, Si=0.5; F_sorbent is the mass flow rate of the deacidification agent required for deacidification, F_sorbent=124.38kg / h, using the theoretical calculated value; T_cyc is the cleaning interval of the filter dust removal device, T_cyc=1h; n_cab is the total number of chambers of the filter dust removal device, n_cab=4.

[0169] In this embodiment, the particle size of the deacidifying agent at the outlet of the grinder in step 5 is variably adjusted. At the beginning of the deacidifying agent pulse injection, the particle size of the deacidifying agent at the outlet of the grinder is controlled to be 70 μm-90 μm by adjusting the operating parameters of the deacidifying agent grinder, and a layer of deacidifying agent powder with a larger particle size is formed on the surface of the filter element, and the injection amount is SV_F_Pulse_1; then the operating parameters of the deacidifying agent grinder are adjusted again to control the particle size of the deacidifying agent at the outlet of the grinder to be 15 μm-25 μm, and the injection amount is SV_F_Pulse_2, which is equal to the difference between SV_F_Pulse and SV_F_Pulse_1;

[0170] Where: SV_F_Pulse_1=K×A_Fil_Ele×n_Fil_Ele=11.4kg;

[0171] Where K is the coating spray coefficient (kg / m 2 ), preferably, K=0.03~0.05, in this embodiment, K=0.03; A_Fil_Ele is the filtration area of ​​a single filter element, A_Fil_Ele=1.32m 2 ; n_Fil_Ele is the number of filter elements installed in a single chamber, n_Fil_Ele=288.

[0172] SV_F_Pulse_2=SV_F_Pulse- SV_F_Pulse_1=15.5-11.4=4.1kg.

[0173] Step 6: Determine whether all chambers of the filter dust removal device 2 have been cleaned. If all chambers have been cleaned, execute step 8; otherwise, execute step 7.

[0174] Step 7: Specify the subsequent chambers for the cleaning procedure, and then proceed to step 4;

[0175] In this embodiment, the principle of designating subsequent chambers may be to perform the dust cleaning procedure in the order of the chambers 201 , 202 , 203 , and 204 .

[0176] As an optional embodiment, in step 7, the selection of subsequent chambers must ensure that all chambers of the filtering dust removal device can be cleaned in a complete cleaning cycle, and each chamber is cleaned only once.

[0177] Step 8: Determine whether to end the automatic control. When the judgment result is "yes", end the automatic control. When the judgment result is "no", execute step 3.

[0178] In summary, the present invention can eliminate the problem of excessive emission of acidic gases such as SO2 and HCl caused by the cleaning of the filter dust removal device and the fluctuation of the concentration of pollutants in the inlet flue gas, improve the distribution effect of flue gas and deacidification agent between the chambers, increase the average deacidification efficiency, reduce the consumption of deacidification agent, and reduce the operating cost of the flue gas purification system. Specifically, the present invention has achieved the following beneficial technical effects compared with the prior art:

[0179] 1. The dry deacidification flue gas purification device and control method of the coupled filtering dust removal device provided by the present invention, the filtering dust removal device is composed of at least two chambers, the chambers are cleaned by offline cleaning, after each chamber is offline cleaned, the porous filter element in the chamber is sprayed with a deacidifying agent pulse jet, and a deacidifying agent powder layer is formed on the surface of the porous filter element in a short time, thereby reducing the influence of the cleaning of the filtering dust removal device on the secondary deacidification effect, and eliminating the problem of excessive emission of acidic gases such as SO2 and HCl caused by the cleaning of the filtering dust removal device.

[0180] 2. Since the porous filter element in the chamber is sprayed with a deacidifying agent pulse jet after the filter-type dust removal device is cleaned, a deacidifying agent powder layer is formed on the surface of the filter element in advance, which can reduce the excessive emission caused by the large fluctuation of HCl and SO2 concentrations in the inlet flue gas of the dry deacidifying flue gas purification device.

[0181] 3. When the deacidifying agent is baking soda and the filter element is a ceramic filter tube, the particle size of the deacidifying agent pulse jet is increased at the beginning of the deacidifying agent pulse jet, and a layer of large-particle deacidifying agent layer is formed on the surface of the filter element, which reduces the probability of fine particles entering the internal pores of the ceramic filter cartridge, increases the service life of the ceramic filter cartridge, reduces the resistance of the flue gas purification system, and reduces the operating cost of the flue gas purification system.

[0182] 4. Through the coordination of pulse injection of deacidifying agent and continuous injection of deacidifying agent, the uniformity of resistance between chambers after cleaning can be improved, the distribution effect of flue gas and deacidifying agent between chambers can be improved, the average deacidification efficiency of dry deacidifying flue gas purification device can be improved, the consumption of deacidifying agent can be reduced, and the operating cost of flue gas purification system can be reduced.

[0183] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A dry deacidification flue gas purification device coupled with a filter-type dust removal device, characterized in that: It includes a deacidification device and a filtering dust removal device connected in sequence, wherein: The deacidification device is connected to a deacidification agent injection system, the deacidification agent injection system is connected to a deacidification agent grinding system, and the deacidification agent is a calcium-based deacidification agent, a sodium-based deacidification agent, or a mixture of a sodium-based deacidification agent and a calcium-based deacidification agent; The filtering dust removal device refers to a device with a porous filter element installed inside and having a dust removal function, wherein the porous filter element is a cloth bag, a ceramic filter tube or a metal filter bag; the filtering dust removal device is composed of at least two chambers, each chamber inlet is provided with a chamber inlet isolation valve, each chamber outlet is provided with a chamber outlet isolation valve, and each chamber inlet is connected to a deacidifying agent pulse jet isolation valve; the total inlet of the filtering dust removal device is provided with an inlet pressure transmitter, and the total outlet is provided with an outlet pressure transmitter and an outlet CEMS; The deacidifier grinding machine in the deacidifier grinding system is an air classifying mill with a remote adjustment function. The operating speed of the classifying wheel built into the deacidifier grinding machine is adjusted by frequency conversion to control the particle size of the deacidifier at the outlet of the grinding machine. At the beginning of the deacidifier pulse injection, the particle size of the deacidifier at the outlet of the grinding machine is controlled to be 70μm~90μm by adjusting the operating parameters of the deacidifier grinding machine, and a layer of deacidifier powder is formed on the surface of the filter element.

2. The dry deacidification flue gas purification device coupled with a filter-type dust removal device according to claim 1 is characterized in that: The deacidifying agent grinding system comprises a deacidifying agent coarse powder bin, a coarse powder bin metering feeding device, a deacidifying agent grinder and a grinder powder conveying fan which are connected in sequence, and the outlet of the grinder powder conveying fan is provided with a first pipeline and a second pipeline; The deacidifying agent injection system includes a deacidifying agent fine powder bin, a deacidifying agent metering and weighing device, a deacidifying agent powder conveying fan, a deacidifying agent powder conveying injector and a deacidifying agent fine powder bin inlet isolation valve. The first pipeline is connected to the deacidifying agent fine powder bin via the deacidifying agent fine powder bin inlet isolation valve, and the second pipeline is connected to each chamber via the deacidifying agent pulse injection isolation valve.

3. The dry deacidification flue gas purification device coupled with a filter-type dust removal device according to claim 2 is characterized in that: The coarse powder bin metering feeding device is a metering rotary feeding valve with a remote adjustment function, which uses frequency conversion to adjust the motor speed of the rotary feeding valve to control the flow of the deacidifying agent entering the deacidifying agent grinder; And / or, the deacidifying agent metering and weighing device adopts a loss-in-weight scale with a remote adjustment function to control the amount of deacidifying agent injected into the deacidifying device as required.

4. The dry deacidification flue gas purification device coupled with a filter-type dust removal device according to claim 1 is characterized in that: The deacidification device is a dry deacidification tower or a deacidification flue.

5. The dry deacidification flue gas purification device coupled with a filter-type dust removal device according to claim 1 is characterized in that: The porous filter element is a catalytic filter element, in which a catalyst is loaded. The catalyst is one or more combinations of an SCR denitration catalyst, a dioxin catalytic oxidation catalyst, and a VOCs catalytic oxidation catalyst.

6. The dry deacidification flue gas purification device coupled with a filter-type dust removal device according to claim 5 is characterized in that: The catalytic filter element is an SCR catalytic filter bag or an SCR catalytic ceramic filter cartridge, and the inlet of the filtering dust removal device is connected to an SCR reducing agent preparation system to provide the reducing agent required for the SCR reaction.

7. The dry deacidification flue gas purification device coupled with a filter-type dust removal device according to claim 6 is characterized in that: The SCR reducing agent is ammonia water. The SCR reducing agent preparation system includes an ammonia water storage tank, an ammonia water delivery pump and an ammonia water atomizing spray gun connected in sequence. The ammonia water in the ammonia water storage tank is delivered to the flue at the inlet of the filtering dust removal device by the ammonia water delivery pump and the ammonia water atomizing spray gun.

8. The control method of the dry deacidification flue gas purification device coupled with the filter-type dust removal device according to any one of claims 1 to 7 is characterized in that: include: Step 1: Set the initial chamber and cleaning start differential pressure Crit_DP for the filter dust removal device to perform the cleaning procedure, and proceed to step 2; Step 2: Start the deacidification agent continuous injection program, and then proceed to step 3; Step 3: Determine whether the measured value PV_DP of the operating differential pressure of the filter dust removal device is greater than or equal to the set dust cleaning start differential pressure Crit_DP. When the judgment result is "yes", execute step 4; when the judgment result is "no", execute step 8; Step 4: Start the chamber cleaning program. After the chamber cleaning program is completed, proceed to step 5; Step 5: Start the deacidification agent pulse injection program, and then proceed to step 6; Step 6: Determine whether all chambers of the filter dust removal device have been cleaned. If all chambers have been cleaned, execute step 8; otherwise, execute step 7. Step 7: Specify the subsequent chambers for the cleaning procedure, and then proceed to step 4; Step 8: Determine whether to end the automatic control. When the judgment result is "yes", end the automatic control. When the judgment result is "no", execute step 3.

9. The method according to claim 8, characterized in that In the step 2, the deacidification agent continuous injection procedure includes: A1: Set the control target value SV_HCl of HCl and the control target value SV_SO2 of SO2 at the outlet of the flue gas purification device; A2: The concentration value of HCl PV_HCl and the concentration value of SO2 PV_SO2 at the outlet of the flue gas purification device are measured by the outlet CEMS; A3: According to the difference between the set acid gas control target value and the acid gas concentration value measured by the outlet CEMS, namely PV_HCl-SV_HCl and PV_SO2-SV_SO2, the mass flow rate of the continuous injection of the deacidifying agent is adjusted through PID; And / or, in step 4, the bin cleaning procedure includes: B1: Close the compartment outlet isolation valve; B2: Clean the filter elements in the chamber by using line-jet pulse cleaning, rotary pulse cleaning or box-type pulse cleaning; And / or, in step 7, the selection of subsequent chambers must ensure that all chambers of the filtering dust removal device can be cleaned in a complete cleaning cycle, and each chamber is cleaned only once.

10. The method according to claim 8, characterized in that In step 5, the deacidification agent pulse injection procedure includes: C1: Close the compartment inlet isolation valve; C2: Open the deacidification agent pulse jet isolation valve and close the deacidification agent fine powder bin inlet isolation valve; C3: Open the compartment outlet isolation valve; C4: Start the powder conveying fan of the grinding machine; C5: Start the deacidifying agent grinder; C6: Adjust the operating parameters of the deacidifying agent grinder so that the particle size of the deacidifying agent at the grinder outlet is within the specified range; C7: Start the metering feeding device of the coarse powder bin and measure the total amount of deacidifying agent PV_F_Pulse entering the bin through the pulse injection of deacidifying agent; C8: When PV_F_Pulse is greater than the set value SV_F_Pulse, the coarse powder bin metering feeding device is stopped; C9: Stop the deacidifier grinder; C10: Stop the powder conveying fan of the deacidifying agent grinding machine; C11: Close the deacidification agent pulse jet isolation valve; C12: Open the chamber inlet isolation valve.

11. The method according to claim 8, characterized in that In step 1, the dust cleaning start differential pressure Crit_DP=1000~2500Pa; And / or, in step 5, the particle size range of the deacidifying agent at the outlet of the grinder is 5 μm to 90 μm, when the absorbent is baking soda, the particle size range is 15 μm to 25 μm, and the setting value SV_F_Pulse of the total amount of pulse injection of the deacidifying agent is in kg; Where: SV_F_Pulse=Si×F_sorbent×T_cyc÷n_cab Wherein, Si is the pulse injection coefficient, that is, the ratio of the pulse injection deacidification dosage to the deacidification dosage required for deacidification, Si=0~1; F_sorbent is the mass flow rate of the deacidification agent required for deacidification, in kg / h, using the multi-year statistical average value of the project or the theoretical calculated value; T_cyc is the cleaning interval of the filter-type dust removal device, in h; n_cab is the total number of chambers of the filter-type dust removal device.

12. The method according to claim 11, characterized in that When the deacidifying agent is baking soda and the filter element is a ceramic filter tube, the particle size of the deacidifying agent at the outlet of the grinder in step 5 is variable and adjustable. At the beginning of the deacidifying agent pulse injection, the operating parameters of the deacidifying agent grinder are adjusted to control the particle size of the deacidifying agent at the outlet of the grinder to be 70 μm to 90 μm, and a layer of deacidifying agent powder with a larger particle size is formed on the surface of the filter element, which is conducive to more thorough dust cleaning. The injection amount is SV_F_Pulse_1; Then, the operating parameters of the deacidifying agent grinder are adjusted again, and the particle size of the deacidifying agent at the grinder outlet is controlled to be 15 μm~25 μm, and the injection amount is SV_F_Pulse_2, which is equal to the difference between SV_F_Pulse and SV_F_Pulse_1; Where: SV_F_Pulse_1=K×A_Fil_Ele×n_Fil_Ele, unit is kg; Where K is the coating spray coefficient, unit is kg / m 2 , K = 0.03 ~ 0.3; A_Fil_Ele is the filtration area of ​​a single filter element, in m 2 ; n_Fil_Ele is the number of filter elements installed in a single chamber.

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