Method and system for integrally removing sulfur oxides, nitrogen oxides and volatile organic compounds in flue gas

Abstract

The invention relates to a method and a system for integrally removing sulfur oxides, nitrogen oxides and volatile organic compounds in flue gas. The method comprises the following steps: pre-desulfurization: enabling flue gas to be in contact with desulfurizer powder to obtain pre-desulfurized flue gas; ammonia mixing: mixing the pre-desulfurized flue gas with an amino denitration agent to obtain mixed ammonia gas; integrated removal: enabling the mixed ammonia gas to be in countercurrent contact with a multi-component removal agent in an integrated removal device; the multi-component removal agent comprises manganese ore, and the manganese ore is selected from one or more of pyrolusite, pyrolusite, manganite, brown manganese ore, hausmannite and rhodochrosite. The method and the system provided by the invention can realize simultaneous removal of sulfur oxides, nitrogen oxides and volatile organic compounds. The system is simple in overall structure, easy to implement and low in investment and operation maintenance cost; the catalyst is high in utilization rate and low in operation cost. The method and the system can be used for the integrated control process of multiple pollutants such as coke oven flue gas and blast furnace flue gas.

Description

Technical Field

[0001] The present invention belongs to the technical field of industrial process waste gas purification, and particularly relates to a method and a system for integrally removing sulfur oxides, nitrogen oxides and volatile organic compounds from flue gas. Background Art

[0002] Flue gas generated after the combustion of coke oven gas or blast furnace gas contains traditional pollutants such as sulfur oxides (SO x ), nitrogen oxides (NO x ), dust, etc. In addition, there is a series of volatile organic compounds (VOCs). VOCs have direct harm to human health. Long-term inhalation will increase the risk of diseases such as leukemia and aplastic anemia. Even if inhaling high-concentration VOCs transiently, it will also have a depressive effect on the central nervous system of the human body, possibly causing symptoms such as dizziness and headache, and even may make people lose consciousness. In addition, the photochemical smog caused by VOCs will also seriously harm human health.

[0003] At present, for SO x in the flue gas after the combustion of coke oven gas or blast furnace gas, since the emission concentration is relatively low (mostly lower than 500 mg / m 3 ), therefore, it is mostly adopted to directly inject baking soda / calcium-based materials into the flue or fill calcium-based desulfurizer in a fixed-bed or moving-bed desulfurization tower, and the removal is achieved by reacting with SO x .

[0004] At present, NO x in the flue gas is mainly removed by selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR). The key of SCR technology lies in the SCR catalyst. Although commercial SCR catalysts have been widely used, their production is not easy and the price is relatively expensive.

[0005] Although the removal of SO x and NO x in the flue gas has been widely applied at present, the removal of VOCs in the flue gas has received less attention. In the VOCs treatment technology, the catalytic oxidation method is considered to be the most efficient treatment method. This method realizes the flameless combustion of VOCs at a relatively low temperature under the action of a catalyst, generating carbon dioxide and water.

[0006] Generally, SO x , NO x , and VOCs in the flue gas are treated in separate units. This technology has many problems such as large occupied space, high cost, and complex system. In view of this problem, some efforts have been made in the prior art.

[0007] For example, Patent Document 1 discloses an integrated deep removal system for multiple pollutants, which includes a high-frequency high-voltage pulse power supply system, a high-voltage electrostatic pollutant removal reaction system, and a spraying system. Among them, the high-frequency high-voltage pulse power supply system uses a high-energy density pulse generator and magnetic switch technology to generate the high-density energy required for the enhanced conversion, absorption, and removal of multiple pollutants; the high-voltage electrostatic pollutant removal reaction system provides a reaction space for pollutant removal and strengthens the energy release of the high-frequency high-voltage pulse power supply system through the optimized configuration of the pole wire and plate; the spraying system provides conditions for the deep removal of pollutants in the reaction system and enhances the removal effect of multiple pollutants.

[0008] Patent Document 2 discloses a circulating fluidized bed photocatalytic reaction system, which includes a circulating fluidized bed reactor, a cyclone separator, a photocatalytic regenerator, a light energy supplement device, a feeding device, and a pneumatic conveying device. This system uses self-luminous photocatalyst particles composed of a long afterglow luminescent material with an upconversion function and a photocatalyst to achieve the functions of light energy absorption and conversion, providing the light source required for the reaction for its own photocatalyst, and solving the problems of photocatalytic reaction, light source input, and photocatalyst regeneration in the process of photocatalytic treatment of industrial waste gas in a circulating fluidized bed manner, so as to achieve the simultaneous purification and removal of SO2, NO x , VOCs.

[0009] In addition, the VOC concentration generated by the combustion of coke oven or blast furnace gas is generally high, the flue gas volume is large, and the temperature of the flue gas after combustion is generally low (usually 180 - 350 °C). Therefore, it is beneficial to remove VOCs at low temperatures.

[0010] Patent Document 3 discloses a device for low-temperature denitrification, desulfurization, and removal of VOCs from flue gas. The device includes an adsorption chamber filled with a porous adsorption medium, and the flue gas flows through the porous adsorption medium in a directional cross-flow manner; a desorption chamber, which is intermittently connected to the adsorption chamber, and the porous adsorption medium can flow from the adsorption chamber into the desorption chamber. The desorption chamber has the characteristic of heating the porous adsorption medium, and the desorption chamber is also provided with a desorption discharge port. This device uses the porous adsorption medium to adsorb and remove nitrogen oxides, sulfides, and VOCs.

[0011] Patent Document 4 discloses a manganese-based catalyst for the co-removal of nitrogen oxides and volatile organic compounds, which efficiently removes NO x at low temperatures and catalytically oxidizes VOCs at medium and high temperatures, achieving the purpose of co-removing pollutants, which can not only purify the air but also reduce costs.

[0012] Patent Document 5 discloses a manganese-based core-shell structure denitrification catalyst, which has the performance of co-removing multiple pollutants, strong sulfur resistance, and high catalytic selectivity, and can efficiently complete denitrification and the oxidation of carbon monoxide and volatile organic compounds.

[0013] Cited References

[0014] Patent Document 1: CN106422704A

[0015] Patent Document 2: CN110368810A

[0016] Patent Document 3: CN116407943A

[0017] Patent Document 4: CN117000265A

[0018] Patent Document 5: CN118698571A Summary of the Invention

[0019] Problems to be Solved by the Invention

[0020] In Patent Documents 1 and 2, high-density energy, light energy, etc. are required, and the device structure is complex and expensive. In Patent Document 3, physical adsorption is used for removal, but the treatment of these pollutants still needs to be faced after removal. The catalyst preparation methods in Patent Documents 4 and 5 are complex and costly, which is not conducive to large-scale application.

[0021] Therefore, there is still an urgent need to develop a method and system for integrally removing SO x , NO x , VOCs in flue gas, which can stably and efficiently remove these pollutants at low temperature, and the catalyst has a short manufacturing cycle and low cost.

[0022] Solutions for Solving the Problems

[0023] In view of the above problems, the inventors of the present invention have conducted in-depth research and found that using manganese ore as a catalytic and desulfurization material can achieve the integrated removal of SO x , NO x , VOCs, thus completing the present invention.

[0024] Specifically, the present invention solves the problems of the present invention through the following solutions.

[0025] [1] A method for integrally removing sulfur oxides, nitrogen oxides and volatile organic compounds in flue gas, comprising the following steps:

[0026] Pre-desulfurization: contacting the flue gas with a desulfurizing agent powder to obtain pre-desulfurized flue gas;

[0027] Ammonia mixing: mixing the pre-desulfurized flue gas with an amino denitrification agent to obtain an ammonia-mixed gas;

[0028] Integrated removal: making the ammonia-mixed gas contact countercurrently with a multi-component removal agent in an integrated removal device;

[0029] The multi-component removal agent contains manganese ore, and the manganese ore is one or more selected from pyrolusite, psilomelane, manganite, braunite, hausmannite, and rhodochrosite.

[0030] [2] According to the method described in [1], wherein,

[0031] The desulfurization agent powder is one or more selected from baking soda, sodium hydroxide, calcium hydroxide, and magnesium hydroxide;

[0032] The amino denitration agent is one or more selected from liquid ammonia, ammonia water, and aqueous urea solution;

[0033] The manganese ore is pretreated manganese ore, and the pretreatment is calcination at 100 - 400 °C;

[0034] The average volume equivalent diameter of the manganese ore is 0.5 mm - 10 mm.

[0035] [3] According to the method described in [1], wherein the content of sulfur oxides in the flue gas is 1000 mg / m 3 Below; in the pre-desulfurization step, the temperature of the flue gas is 180 - 400 °C; in the integrated removal step, the temperature of the mixed ammonia gas is 180 - 400 °C, and the time of countercurrent contact is 2 - 8 s.

[0036] [4] According to the method described in [1], wherein the multi-component removal agent further contains inert particles, and the inert particles do not undergo physical and chemical changes at a temperature of 180 - 400 °C,

[0037] Preferably, the inert particles are one or more selected from ceramic particles, high-temperature resistant glass particles, and stainless steel particles; the inert particles are one or two of spherical and rod-shaped; the average volume equivalent diameter of the inert particles is 5 - 30 mm.

[0038] [5] According to the method described in [1], it further includes the following steps:

[0039] Manganese ore regeneration: The manganese ore after the integrated removal step is washed with water and then calcined at 100 - 400 °C to obtain regenerated manganese ore;

[0040] Manganese sulfate recovery: The wastewater generated during the water washing in the manganese ore regeneration step is subjected to solid-liquid separation, and then the liquid phase obtained from the solid-liquid separation is evaporated and crystallized to obtain a product containing manganese sulfate.

[0041] [6] A system for the method described in any one of [1] to [5], which sequentially includes a pre-desulfurization device, a mixed ammonia device, and an integrated removal device, wherein

[0042] The pre-desulfurization device includes a pre-desulfurization reactor and a desulfurizing agent powder injector. The pre-desulfurization reactor has a flue gas inlet and a pre-desulfurized flue gas outlet. The desulfurizing agent powder injector is configured to inject desulfurizing agent powder into the pre-desulfurization reactor.

[0043] The ammonia mixing device includes an ammonia mixing reactor and an amino denitrification agent injector. The ammonia mixing reactor has a pre-desulfurized flue gas inlet and an ammonia mixed gas outlet. The amino denitrification agent injector is configured to inject amino denitrification agent into the ammonia mixing reactor.

[0044] The integrated removal device includes one removal reactor or two series-connected removal reactors. Each removal reactor has a gas inlet, a gas outlet, a multi-component removal agent inlet, and a multi-component removal agent outlet.

[0045] A perforated plate is provided between the ammonia mixing device and the integrated removal device.

[0046] [7] According to the system described in [6], wherein the integrated removal device includes two series-connected removal reactors, and the connection mode of the two series-connected removal reactors is: the gas outlet of the first removal reactor is connected to the gas inlet of the second removal reactor, and the multi-component removal agent inlet of the first removal reactor is connected to the multi-component removal agent outlet of the second removal reactor.

[0047] [8] According to the system described in [6] or [7], wherein the removal reactors are independently a moving bed reactor, a fixed bed reactor, a fluidized bed reactor, or a spouted bed reactor. Preferably, the outside of the removal reactor has a heat preservation device or the removal reactor is made of heat preservation material. More preferably, the removal reactor has a metal lining and an outer layer made of heat preservation material.

[0048] [9] According to the system described in [6], wherein the perforated plate has a plurality of through holes, and the diameter of the holes is 0.5 mm to 5 mm; preferably, the surface of the perforated plate is made of a corrosion-resistant material.

[0049]

[10] According to the system described in [6], which further includes a manganese ore regeneration device and an optional manganese sulfate recovery device, wherein

[0050] The manganese ore regeneration device includes a water washing reactor and a calcination reactor. The water washing reactor is configured to wash the manganese ore in the multi-component removal agent discharged from the integrated removal device, and the calcination reactor is configured to calcine the washed manganese ore.

[0051] The manganese sulfate recovery device includes a solid-liquid separator and an evaporation crystallizer. The solid-liquid separator is configured to perform solid-liquid separation on the wastewater generated in the water washing reactor, and the evaporation crystallizer is configured to perform evaporation crystallization on the liquid phase discharged from the solid-liquid separator.

[0052] Effects of the Invention

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] 1. Able to remove SO in an integrated manner x 、NO x , VOCs, SO can be achieved through only one process or in only one system x 、NO x Integrated synergistic removal of VOCs;

[0055] 2. The overall structure of the system is simple and easy to implement, and the equipment used is conventional equipment, the process is simple, and the investment and operation and maintenance costs are low;

[0056] 3. SO x 、NO x The removal rate of VOCs is high, and can reach 90% removal rate or meet emission requirements at a temperature of 180-400℃;

[0057] 4. Good operating stability, can maintain VOCs and NO for a long time x A conversion rate of greater than 90%;

[0058] 5. High catalyst utilization rate and low operating cost;

[0059] 6. The failed remover can be regenerated and valuable by-products can be recovered;

[0060] 7. It has realized low-cost control of VOCs in coking, steel and other industries, with significant environmental and social benefits;

[0061] 8. Can be applied on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A schematic diagram of a preferred embodiment of the present invention;

[0063] Figure 2 It is a schematic diagram of a second preferred embodiment of the present invention.

[0064] Description of Reference Numerals

[0065] Figure 1In the figure: 1 - pre - desulfurization reactor; 2 - ammonia - mixing reactor; 3 - desulfurizer powder injector; 4 - amino - denitration agent injector; 5 - removal reactor; 6 - manganese ore; 7 - inert particles; 8 - perforated plate; 9 - flue gas inlet; 10 - multi - component removal agent inlet; 11 - multi - component removal agent outlet; 12 - gas outlet; 13 - desulfurizer powder discharge outlet.

[0066] Figure 2 In the figure: 001 - pre - desulfurization - ammonia - mixing reactor; 003 - desulfurizer powder injector; 004 - amino - denitration agent injector; 005 - first removal reactor; 105 - second removal reactor; 006 - manganese ore; 007 - inert particles; 008, 013 - perforated plate; 009 - flue gas inlet; 010, 110 - multi - component removal agent inlet; 011, 111 - multi - component removal agent outlet; 012 - gas outlet. Detailed implementation mode

[0067] Hereinafter, the content of the present invention will be described in detail. The description of the technical features recorded below is based on representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples.

[0068] <Terms and definitions>

[0069] In this specification, the "combination" described for the reactor means that two or more reactors are directly or connected through pipelines in series or parallel.

[0070] In this specification, "upstream" and "downstream" are described based on the flow direction of the gas to be processed.

[0071] In this specification, the numerical range expressed as "numerical value A~numerical value B" means a range including the endpoint numerical values A and B.

[0072] In this specification, the numerical range expressed as "above" or "below" means a numerical range including this number.

[0073] In this specification, the meaning expressed by "can" includes both the meaning of performing a certain treatment and the meaning of not performing a certain treatment.

[0074] In this specification, the use of "optionally" or "optional" means that certain substances, components, execution steps, applied conditions, etc. are used or not used.

[0075] In this specification, the unit names used are all international standard unit names, and unless otherwise specified, the "%" used represents volume percentage content.

[0076] In this specification, the "preferred embodiments", "embodiments", etc. mentioned refer to the specific elements (e.g., features, structures, properties, and / or characteristics) related to the embodiments, which are included in at least one of the embodiments described herein, and may or may not be present in other embodiments. Additionally, it should be understood that the elements can be combined in various embodiments in any suitable manner.

[0077] <Method>

[0078] A method for integrally removing sulfur oxides, nitrogen oxides, and volatile organic compounds from flue gas, characterized by comprising the following steps:

[0079] Pre-desulfurization: contacting the flue gas with a desulfurizing agent powder to obtain pre-desulfurized flue gas;

[0080] Ammonia mixing: mixing the pre-desulfurized flue gas with an amino denitrating agent to obtain an ammonia-mixed gas;

[0081] Integrated removal: making the ammonia-mixed gas contact countercurrently with a multi-component removing agent in an integrated removal device;

[0082] The multi-component removing agent contains manganese ore, and the manganese ore is one or more selected from pyrolusite, psilomelane, manganite, braunite, hausmannite, and rhodochrosite.

[0083] In some embodiments, the method of the present invention further comprises the following steps:

[0084] Manganese ore regeneration: washing the manganese ore after the integrated removal step, and then calcining it at 100 - 400 °C to obtain regenerated manganese ore.

[0085] In some embodiments, the method of the present invention further comprises the following steps:

[0086] Manganese sulfate recovery: performing solid-liquid separation on the wastewater generated during the washing in the manganese ore regeneration step, and then performing evaporation crystallization on the liquid phase obtained from the solid-liquid separation to obtain a product containing manganese sulfate.

[0087] In the method for integrally removing sulfur oxides, nitrogen oxides, and volatile organic compounds from flue gas of the present invention (also simply referred to as the "integrated removal method" or "the method of the present invention" in the context), manganese ore is used as a catalyst and desulfurizing agent for integrated removal. By making the manganese ore contact countercurrently with the gas, the purpose of integrated removal is achieved. Components such as Mn3O4, Mn2O3, and MnO2 in the manganese ore are denitration catalysts and also catalysts for removing volatile organic compounds, and can catalyze the reaction of nitrogen oxides with the amino denitrating agent to achieve denitration and simultaneously remove volatile organic compounds.

[0088] A further explanation of the integrated removal principle of the present invention is as follows: From the perspective of manganese ore, the unused manganese ore contains relatively more Mn3O4, Mn2O3, and MnO2, and relatively less manganese sulfate (MnSO4) and calcium sulfate (CaSO4), and has relatively high catalytic performance for denitrification and volatile organic compound removal. During the countercurrent contact process, the sulfur content in the manganese ore gradually increases with the contact with the gas, and its catalytic performance for denitrification and volatile organic compound removal gradually decreases. However, the desulfurization performance of such manganese ore is still excellent and is suitable for desulfurization. From the perspective of the gas, the content of sulfur oxides in the ammonia-mixed gas is relatively high. After entering the integrated removal device, it first contacts the manganese ore with low catalytic performance but still excellent desulfurization performance for the desulfurization reaction, so that the sulfur content gradually decreases. Then, with the progress of the countercurrent contact, it gradually contacts the manganese ore with high catalytic performance to remove nitrogen oxides and volatile organic compounds, thereby completing the integrated removal of sulfur oxides, nitrogen oxides, and volatile organic compounds.

[0089] The present invention enables the countercurrent contact between manganese ore and gas, thereby integrally removing multiple components in one step. The method is simple and easy to implement, the raw materials are cheap and easily available, the utilization rate is high, and the operating cost is low.

[0090] Moreover, in the method of the present invention, the used manganese ore can be recovered and regenerated, and the regenerated manganese ore still has excellent catalytic performance for nitrogen oxide and volatile organic compound removal. In addition, the wastewater generated in the water washing step during the regeneration process contains manganese sulfate components, and manganese sulfate raw materials can be by-produced through operations such as solid-liquid separation and evaporation crystallization.

[0091] The following separately describes each step of the method of the present invention.

[0092] Pre-desulfurization

[0093] In the pre-desulfurization step, the flue gas is brought into contact with the desulfurizer powder to obtain pre-desulfurized flue gas.

[0094] Through pre-desulfurization, most of the sulfur oxides in the flue gas can be removed, which is beneficial to the subsequent integrated removal step.

[0095] In this specification, "flue gas" has its usual meaning in the art, and it includes sulfur oxides, nitrogen oxides, and volatile organic compounds.

[0096] Among them, the sulfur oxides are one or two selected from sulfur dioxide and sulfur trioxide; the nitrogen oxides are one or more selected from nitric oxide, nitrogen dioxide, and dinitrogen pentoxide; the volatile organic compounds are any organic compounds that can participate in atmospheric photochemical reactions, including aromatic hydrocarbons, phenols, etc., such as toluene, xylene, phenol, naphthalene, etc.

[0097] In some embodiments, the flue gas (gas to be treated) is the gas obtained after combustion of coke oven flue gas, blast furnace flue gas or other combustible gases.

[0098] Preferably, the content of sulfur oxides in the flue gas is 1000 mg / m 3 The following (for example, 800 mg / m 3 The following, 600 mg / m 3 The following), the content of nitrogen oxides is 200 mg / m 3 The following (for example, 180 mg / m 3 The following), and the content of volatile organic compounds is 200 mg / m 3 The following (for example, 180 mg / m 3 The following, 160 mg / m 3 The following, 140 mg / m 3 The following).

[0099] In some embodiments, the desulfurization agent powder is granular, with an average particle size of 10 - 60 μm, preferably 20 - 50 μm.

[0100] Preferably, the desulfurization agent powder is one or more selected from sodium bicarbonate, sodium hydroxide, calcium hydroxide, and magnesium hydroxide. More preferably, the specific surface area of the desulfurization agent powder is 30 m 2 / g or more, preferably 35 m 2 / g or more.

[0101] Preferably, the dosage of the desulfurization agent powder is 1.5 - 3 times the molar amount of sulfur element in the flue gas.

[0102] Preferably, in the pre - desulfurization step, the temperature of the flue gas is 180 - 400 °C, for example, 200 - 350 °C.

[0103] Ammonia mixing step

[0104] In the ammonia - mixing step, the pre - desulfurized flue gas is mixed with an amino - denitration agent to obtain an ammonia - mixed gas. The amino - denitration agent introduced in the ammonia - mixing step is used for the subsequent nitrogen oxide removal (denitration) reaction.

[0105] Preferably, the amino - denitration agent is one or more selected from liquid ammonia, ammonia water, and aqueous urea solution.

[0106] Preferably, the concentration of ammonia water is 15 - 20 mass%.

[0107] Preferably, the concentration of aqueous urea solution is 20 - 40 mass%.

[0108] Preferably, the dosage of the amino - denitration agent is 1.5 - 3 times the molar amount of nitrogen element in the flue gas.

[0109] Integrated removal step

[0110] In the integrated removal step, in an integrated removal device, the ammonia-containing gas is brought into countercurrent contact with a multi-component removal agent, thereby achieving the integrated removal of sulfur oxides, nitrogen oxides, and volatile organic compounds.

[0111] In this specification, "countercurrent contact" has its ordinary meaning in the art, specifically referring to making the gas and solid move in opposite directions and come into contact simultaneously in a reaction device, or in the case where the reaction device includes multiple reactors (multiple stages), the gas and solid pass through each reactor (each stage) in opposite directions in sequence.

[0112] In the present invention, the multi-component removal agent contains manganese ore, and the manganese ore is one or more selected from pyrolusite, psilomelane, manganite, braunite, hausmannite, and rhodochrosite.

[0113] Preferably, the average volume equivalent diameter of the manganese ore is 0.5 mm to 10 mm.

[0114] Preferably, the manganese ore is pretreated manganese ore, and the pretreatment is calcination at 100 to 400 °C (such as 100 to 300 °C, or for example 100 to 200 °C). The preferred calcination time is 0.1 to 1 hour, more preferably 0.2 to 0.8 hour.

[0115] Preferably, the ammonia-containing gas is brought into countercurrent contact with the multi-component removal agent at a temperature of 180 to 400 °C.

[0116] Preferably, from the perspective of the removal rate, the countercurrent contact time is 2 s or more, preferably 3 s or more, more preferably 4 s or more.

[0117] Preferably, from the perspective of operating efficiency, the countercurrent contact time is 8 s or less, preferably 7 s or less, more preferably 6 s or less, and also for example 5 s, etc.

[0118] In some embodiments, the multi-component removal agent further contains inert particles, and the inert particles do not undergo physical (such as softening) and chemical changes at a temperature of 180 to 400 °C. The inert particles are used to intercept and disperse the manganese ore to increase the contact time and efficiency between the gas and the manganese ore.

[0119] Preferably, the inert particles are one or more selected from ceramic particles, high-temperature resistant glass particles, and stainless steel particles.

[0120] Preferably, the inert particles are one or both of spherical and rod-shaped.

[0121] Preferably, the average volume equivalent diameter of the inert particles is 5 to 30 mm.

[0122] In some embodiments, the integrated removal step can be divided into, for example, two sub-steps for implementation. Preferably, the integrated removal step comprises the following two sub-steps:

[0123] Sub-step A: bringing the ammonia-containing gas into contact with the multi-component removal agent that has undergone sub-step B;

[0124] Sub-step B: bringing the ammonia-containing gas that has undergone sub-step A into contact with the multi-component removal agent.

[0125] Those skilled in the art will understand that when the method of the present invention operates stably, sub-step A and sub-step B are carried out simultaneously to achieve countercurrent contact between the ammonia-containing gas and the multi-component removal agent.

[0126] Preferably, in sub-step A and sub-step B, the gas to be treated is respectively brought into countercurrent contact with the multi-component removal agent.

[0127] Preferably, in the integrated removal step, the space velocity in the reactor is 20,000 - 50,000 ml / g·h, preferably 30,000 - 40,000 ml / g·h.

[0128] Manganese ore regeneration

[0129] In some embodiments, the method of the present invention further includes a manganese ore regeneration step. By washing the manganese ore after the integrated removal step and then calcining it at 100 - 400 °C (for example, 100 - 300 °C, or for another example, 100 - 200 °C), the regenerated manganese ore is obtained.

[0130] By carrying out the above-mentioned manganese ore regeneration step, the part on the surface of the manganese ore that has undergone chemical reactions and thus lost its desulfurization and catalytic performance can be removed, exposing the fresh manganese ore. Thus, the regenerated manganese ore can be recycled and fully utilized in the integrated removal step.

[0131] Manganese sulfate recovery

[0132] In some embodiments, the method of the present invention further includes a manganese sulfate recovery step. During the water washing process in the manganese ore recovery step, the manganese sulfate generated during desulfurization dissolves in water. By performing solid-liquid separation on the wastewater and evaporating and crystallizing the liquid phase, a product containing manganese sulfate can be obtained.

[0133] By recovering manganese sulfate, the economic benefits of the method of the present invention can be further improved.

[0134] The removal rate of the method of the present invention is high. The content of sulfur oxides in the purified flue gas after removal by the method of the present invention is 20 mg / m 3 The following (for example, 15 mg / m3 The following is 10 mg / m 3 The following is 5 mg / m 3 The following), and the content of nitrogen oxides is 50 mg / m 3 The following (for example, 40 mg / m 3 The following, 30 mg / m 3 The following), and the content of volatile organic compounds is 60 mg / m 3 The following (for example, 50 mg / m 3 The following, 40 mg / m 3 The following).

[0135] <System>

[0136] An object of the present invention is to provide a system for synergistically removing sulfur oxides, nitrogen oxides, and volatile organic compounds in flue gas, which sequentially includes a pre-desulfurization device, an ammonia mixing device, and an integrated removal device, wherein

[0137] The pre-desulfurization device includes a pre-desulfurization reactor and a desulfurizing agent powder injector. The pre-desulfurization reactor has a flue gas inlet and a pre-desulfurized flue gas outlet. The desulfurizing agent powder injector is configured to inject desulfurizing agent powder into the pre-desulfurization reactor.

[0138] The ammonia mixing device includes an ammonia mixing reactor and an amino denitrification agent injector. The ammonia mixing reactor has a pre-desulfurized flue gas inlet and an ammonia mixed gas outlet. The amino denitrification agent injector is configured to inject amino denitrification agent into the ammonia mixing reactor.

[0139] The integrated removal device includes 1 removal reactor or 2 series-connected removal reactors. Each removal reactor has a gas inlet, a gas outlet, a multi-component removal agent inlet, and a multi-component removal agent outlet.

[0140] A perforated plate is provided between the ammonia mixing device and the integrated removal device.

[0141] In some embodiments, the method of the present invention further includes a manganese ore regeneration device and an optional manganese sulfate recovery device, wherein

[0142] The manganese ore regeneration device includes a water washing reactor and a calcination reactor. The water washing reactor is configured to wash the manganese ore in the multi-component removal agent discharged from the integrated removal device. The calcination reactor is configured to calcine the washed manganese ore.

[0143] The manganese sulfate recovery device includes a solid-liquid separator and an evaporation crystallizer. The solid-liquid separator is configured to perform solid-liquid separation on the wastewater generated in the water washing reactor. The evaporation crystallizer is configured to perform evaporation crystallization on the liquid phase discharged from the solid-liquid separator.

[0144] The following describes in detail various aspects of the system of the present invention.

[0145] Pre-desulfurization device

[0146] The pre-desulfurization device includes a pre-desulfurization reactor and a desulfurizer powder injector. Flue gas enters the pre-desulfurization reactor from the flue gas inlet of the pre-desulfurization reactor, and in the pre-desulfurization reactor, it is mixed with the desulfurizer powder ejected by the desulfurizer powder injector and undergoes a pre-desulfurization reaction to obtain pre-desulfurized gas.

[0147] The present invention has no particular limitation on the installation position and method of the desulfurizer powder injector, and those skilled in the art can select according to needs. Preferably, the desulfurizer powder injector is arranged at the flue gas inlet of the pre-desulfurization reactor or in the upstream flue, and is configured to inject the desulfurizer powder against the flow of the gas.

[0148] In some embodiments, the flue gas inlet of the pre-desulfurization reactor is connected to a flue for transporting flue gas. For example, the flue can be the exhaust passage of other equipment connected to the system of the present invention. This other equipment can be, for example, equipment that generates flue gas, such as various combustion furnaces, carbonization furnaces, etc.

[0149] The pre-desulfurized flue gas outlet of the pre-desulfurization reactor is connected to the pre-desulfurized flue gas inlet of the ammonia mixing reactor. In some embodiments, the pre-desulfurization reactor is directly connected to the ammonia mixing reactor, so the connection point is both the pre-desulfurized flue gas outlet of the pre-desulfurization reactor and the pre-desulfurized flue gas inlet of the ammonia mixing reactor.

[0150] In some embodiments, the pre-desulfurization reactor is also provided with a desulfurizer powder discharge outlet for discharging the desulfurizer powder after the pre-desulfurization reaction.

[0151] In some embodiments, the pre-desulfurization device further includes a gas-solid separator. The gas-solid separator is used to separate the pre-desulfurized flue gas from the desulfurizer powder. The separated pre-desulfurized flue gas is transported to the ammonia mixing device, and the desulfurizer powder is separated and discharged from the pre-desulfurization device.

[0152] Ammonia mixing device

[0153] The ammonia mixing device includes an ammonia mixing reactor and an amino denitration agent injector. The pre-desulfurized flue gas enters the ammonia mixing reactor from the pre-desulfurized flue gas inlet of the ammonia mixing reactor, and in the ammonia mixing reactor, it is mixed with the amino denitration agent ejected by the amino denitration agent injector to obtain ammonia-mixed gas.

[0154] The present invention has no particular limitation on the installation position and method of the amino denitration agent injector, and those skilled in the art can select according to needs. Preferably, the amino denitration agent injector is arranged at the pre-desulfurized flue gas inlet of the ammonia mixing reactor and configured to inject the amino denitration agent against the gas flow.

[0155] The ammonia mixing gas outlet of the ammonia mixing reactor is connected to the gas inlet of the removal reactor. In some embodiments, the ammonia mixing reactor is directly connected to the removal reactor, so the connection point is both the ammonia mixing gas outlet of the ammonia mixing reactor and the gas inlet of the removal reactor.

[0156] In some embodiments, the pre-desulfurization device and the ammonia mixing device can share a reactor (pre-desulfurization - ammonia mixing reactor). For example, a desulfurizing agent powder injector and an amino denitration agent injector are respectively arranged in the gas flow path of a reactor. Preferably, the desulfurizing agent powder injector is arranged upstream of the amino denitration agent injector.

[0157] In some embodiments, the desulfurizing agent powder discharge port can also be arranged at the lower part of the ammonia mixing reactor.

[0158] Integrated removal device

[0159] In some embodiments, the integrated removal device includes one removal reactor, which has a gas inlet, a gas outlet, a multi-component removal agent inlet, and a multi-component removal agent outlet. This one removal reactor is configured to make the gas (ammonia mixing gas) and the multi-component removal agent contact countercurrently inside it.

[0160] Preferably, the gas inlet and the multi-component removal agent outlet are arranged at the lower part or the bottom of the removal reactor, and the gas outlet and the multi-component removal agent inlet are arranged at the upper part or the top of the removal reactor.

[0161] In some embodiments, the integrated removal device includes two series-connected removal reactors. The connection mode of the two series-connected removal reactors is: the gas outlet of the first removal reactor is connected to the gas inlet of the second removal reactor, and the multi-component removal agent inlet of the first removal reactor is connected to the multi-component removal agent outlet of the second removal reactor.

[0162] During the operation of the device, gas enters from the gas inlet of the first removal reactor, contacts with the multi-component removal agent in the first removal reactor, is discharged from the gas outlet of the first removal reactor, and enters the second removal reactor through the gas inlet of the second removal reactor. After contacting with the multi-component removal agent in the second removal reactor, it is discharged from the gas outlet of the second removal reactor; the multi-component removal agent enters from the multi-component removal agent inlet of the second removal reactor, contacts with the gas in the second removal reactor, is discharged from the multi-component removal agent outlet of the second removal reactor, enters the first removal reactor through the multi-component removal agent inlet of the first removal reactor, and is discharged from the multi-component removal agent outlet of the first removal reactor after contacting with the gas in the first removal reactor.

[0163] In some embodiments, the first removal reactor is directly connected to the second removal reactor, so the connection point is both the gas outlet of the first removal reactor and the gas inlet of the second removal reactor.

[0164] Preferably, in the first removal reactor and the second removal reactor, the gas is in countercurrent contact with the multi-component removal agent. However, those skilled in the art should understand that in the case where the above integrated removal device includes two series-connected removal reactors, even if the gas is in contact with the multi-component removal agent in other ways (such as co-current contact) in each removal reactor, the gas and the multi-component removal agent still achieve countercurrent contact in the entire integrated removal device.

[0165] Preferably, the removal reactor (in the case of using two removal reactors, the two removal reactors independently) is a moving bed reactor, a fixed bed reactor, a fluidized bed reactor or a spouted bed reactor.

[0166] Preferably, the outside of the removal reactor has heat preservation equipment or the catalytic reactor is made of refractory heat preservation material. More preferably, the catalytic reactor has a metal lining and an outer layer made of heat preservation material. For the specific heat preservation material, the present invention has no special limitation, and it can be any heat preservation material known in the art suitable for the reactor, including but not limited to ceramics, mineral wool (such as glass wool) and polymer foaming materials, etc.

[0167] Perforated plate

[0168] In the system of the present invention, a perforated plate is provided between the ammonia mixing device and the integrated removal device. The setting of the perforated plate can play a role in evenly distributing the incoming gas, and enables the gas in the ammonia mixing device to enter the integrated removal device, while the materials in the integrated removal device will not enter the ammonia mixing device.

[0169] In some embodiments, the perforated plate has a plurality of through holes for gas to pass through.

[0170] Preferably, the diameter of the through hole is 0.5 mm to 5 mm, preferably 1 mm to 4 mm, more preferably 1.5 mm to 3 mm.

[0171] Preferably, the area porosity of the perforated plate is 30 to 70%, preferably 40 to 60%.

[0172] Preferably, the surface of the perforated plate is made of a corrosion-resistant material, such as stainless steel, ceramics, plastics, etc.

[0173] In an embodiment where the integrated removal device includes 2 removal reactors, a perforated plate may be provided in the gas flow path between the 2 removal reactors. For example, a perforated plate may be provided at the gas outlet of the first removal reactor, the gas inlet of the second removal reactor, or in the pipeline between the gas outlet of the first removal reactor and the gas inlet of the second removal reactor. In an embodiment where the first removal reactor is directly connected to the second removal reactor, a perforated plate may be provided at the connection.

[0174] In some embodiments, a perforated plate is provided at the gas outlet of the integrated removal device to prevent the multi-component removal agent from leaving through the gas outlet.

[0175] Manganese ore regeneration device

[0176] In some embodiments, the system of the present invention further includes a manganese ore regeneration device. The manganese ore regeneration device includes a water washing reactor and a calcination reactor.

[0177] The water washing reactor is configured to wash the manganese ore in the multi-component removal agent discharged from the integrated removal device. The present invention does not particularly limit the specific structure of the water washing reactor, which may be any suitable reactor in the art, including but not limited to a spray water washing tower, a slurry bed, etc.

[0178] The calcination reactor is configured to calcine the washed manganese ore. The present invention does not particularly limit the specific structure of the calcination reactor, which may be any suitable reactor in the art, including but not limited to a rotary kiln, a horizontal moving bed, a vertical moving bed, etc.

[0179] In some embodiments, a separator is further included upstream of the water washing reactor, which is configured to separate the manganese ore in the multi-component removal agent, and more specifically, separate the manganese ore from other components in the multi-component removal agent, especially inert particles. This separation can be carried out by, for example, screening.

[0180] Those skilled in the art should understand that even if the used multi-component removal agent is not separated and the whole is transported to the manganese ore regeneration device for water washing and calcination, the regeneration of manganese ore can also be achieved.

[0181] Manganese sulfate recovery device

[0182] In some embodiments, the system of the present invention further includes a manganese sulfate recovery device. The manganese sulfate recovery device includes a solid-liquid separator and an evaporation crystallizer.

[0183] The solid-liquid separator is configured to perform solid-liquid separation on the wastewater generated in the water washing reactor. The present invention has no particular limitation on the specific structure of the solid-liquid separator, and it can be any suitable solid-liquid separator in the art, such as various filters.

[0184] The evaporation crystallizer is configured to perform evaporation crystallization on the liquid phase discharged from the solid-liquid separator, thereby obtaining a product containing manganese sulfate. This product can be further purified to obtain manganese sulfate as an industrial raw material. The present invention has no particular limitation on the specific structure of the evaporation crystallizer, and it can be any suitable evaporation crystallizer in the art.

[0185] Other components

[0186] In addition to the devices described above, the system of the present invention also optionally includes other components, such as the pre-desulfurization device, ammonia mixing device, integrated removal device, manganese ore regeneration device, various auxiliary equipment of the manganese sulfate recovery device, and connecting pipelines, etc. Examples of these other components include but are not limited to flue gas conveying devices, storage and / or conveying devices for desulfurization agent powder, storage and / or conveying devices for amino denitration agent, storage and / or conveying devices for water, storage and / or conveying devices for multi-component removal agent, etc.

[0187] The preferred embodiments of the present invention are described below with reference to the accompanying drawings.

[0188] <Preferred Embodiment 1>

[0189] As Figure 1 shown, the system of the present invention includes a pre-desulfurization device, an ammonia mixing device, and an integrated removal device. The pre-desulfurization device includes a pre-desulfurization reactor 1 and a desulfurization agent powder injector 3. The ammonia mixing device includes an ammonia mixing reactor 2 and an amino denitration agent injector 4. The integrated removal device includes a removal reactor 5, in which manganese ore 6 and inert particles 7 are filled. A perforated plate 8 is provided between the ammonia mixing reactor 2 and the removal reactor 5. In this embodiment, the pre-desulfurization reactor 1 is directly connected to the ammonia mixing reactor 2, the ammonia mixing reactor 2 is directly connected to the removal reactor 5, and a desulfurization agent powder discharge port 13 is further provided at the lower part of the ammonia mixing reactor 2.

[0190] The flue gas is sent into the pre-desulfurization reactor 1 through the flue gas inlet 9, contacts with the desulfurizing agent powder ejected by the desulfurizing agent powder ejector 3, and the pre-desulfurized flue gas is obtained; after leaving the desulfurization reactor 1, the pre-desulfurized flue gas enters the ammonia-mixing reactor 2, mixes with the ammonia-based denitration agent ejected by the ammonia-based denitration agent ejector 4, and the ammonia-mixed gas is obtained; the ammonia-mixed gas enters the removal reactor 5 through the porous plate 8 arranged at the ammonia-mixed gas outlet at the top of the ammonia-mixing reactor 2 (the gas inlet at the bottom of the removal reactor 5), and countercurrently contacts with the manganese ore 6 and the inert particles 7 entering the removal reactor 5 from the multi-component removal agent inlet 10 arranged at the top of the removal reactor 5 during the upward flow, and leaves from the gas outlet 12 arranged at the upper part of the removal reactor 5; the manganese ore 6 and the inert particles 7 move downward in the removal reactor 5 and are discharged from the multi-component removal agent outlet 11 arranged at the bottom of the removal reactor 5, and then are transported to a manganese ore recovery device (not shown).

[0191] <Preferred Embodiment II>

[0192] As Figure 2 shown, the system of the present invention includes a pre-desulfurization device, an ammonia-mixing device and an integrated removal device. Among them, the pre-desulfurization device and the ammonia-mixing device share a reactor, that is, the pre-desulfurization-ammonia-mixing reactor 001. The desulfurizing agent powder ejector 003 and the ammonia-based denitration agent ejector 004 are sequentially arranged in the pre-desulfurization-ammonia-mixing reactor 001 along the gas flow direction; the integrated removal device includes two series-connected removal reactors, that is, the first removal reactor 005 and the second removal reactor 105. A porous plate 008 is arranged between the pre-desulfurization-ammonia-mixing reactor 001 and the removal reactor 005. In this embodiment, the first removal reactor 005 and the second removal reactor 105 are directly connected, and a porous plate 013 is also arranged between them.

[0193] The flue gas is sent into the pre-desulfurization - ammonia mixing reactor 001 through the flue gas inlet 009, and during the flowing process, it first contacts with the desulfurizing agent powder ejected by the desulfurizing agent powder ejector 003 and is transformed into pre-desulfurized flue gas, and then is mixed with the amino denitration agent ejected by the amino denitration agent ejector 004 to become ammonia-mixed gas; the ammonia-mixed gas enters the removal reactor 005 through the porous plate 008 arranged at the ammonia-mixed gas outlet of the pre-desulfurization - ammonia mixing reactor 001 (the gas inlet of the removal reactor 005), contacts with the manganese ore 006 and the inert particles 007 in the removal reactor 005, then leaves the removal reactor 005 and enters the removal reactor 105, continues to contact with the manganese ore 006 and the inert particles 007, and after the contact is completed, it leaves from the second removal reactor gas outlet 012; the manganese ore 006 and the inert particles 007 first enter the removal reactor 105 from the multi-component removal agent inlet 110 of the removal reactor 105, are discharged from the multi-component removal agent outlet 111 after use, then are transported to the removal reactor 005 through the multi-component removal agent inlet 010 of the removal reactor 005, are discharged through the multi-component removal agent outlet 011 after use, and then are transported to a manganese ore recovery device (not shown).

[0194] Example

[0195] The embodiments of the present invention will be described in detail below in conjunction with the examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. The specific conditions not specified in the examples are carried out according to the conventional conditions or the conditions recommended by the equipment manufacturer.

[0196] Example 1

[0197] This example is carried out using the system of the first preferred embodiment shown in Figure 1 , in which the removal reactor 5 is a moving bed reactor, the pore diameter of the porous plate 8 is 2 mm, and the porosity is 50%.

[0198] The gas to be treated is coke oven flue gas, and the specific parameters are: temperature 250 °C, SO2 concentration 400 mg / m 3 , NO x concentration 150 mg / m 3 , VOCs concentration 120 mg / m 3 .

[0199] The desulfurizing agent powder is calcium hydroxide powder with a specific surface area of 40 m 2 / g and an average particle size of 30 μm, and the addition amount is Ca / S = 2 in terms of molar. The amino denitration agent is liquid ammonia with a concentration of 100%, and the addition amount is NH3 / NO x = 2 in terms of molar.

[0200] The manganese ore is pyrolusite with a manganese content of 18% by mass. Before use, it is calcined at 105 °C for 30 min, and the average volume equivalent diameter is 5 mm.

[0201] The space velocity in the removal reactor is 35000 ml / g·h, and the average gas residence time is 4 s. After integrated removal, in the gas discharged from the outlet of the removal reactor: SO2 is 3 mg / m 3 , NO x is 35 mg / m 3 , VOCs is 35 mg / m 3 .

[0202] Example 2

[0203] This example is carried out using the system of Preferred Embodiment 2 shown in Figure 2 , where the first removal reactor 005 and the second removal reactor 105 are both moving bed reactors, the pore diameters of the perforated plates 008 and 013 are 2 mm, and the porosity is 50%.

[0204] The gas to be treated is coke oven flue gas, and the specific parameters are: temperature 250 °C, SO2 concentration 400 mg / m 3 , NO x concentration 150 mg / m 3 , VOCs concentration 120 mg / m 3 .

[0205] The desulfurizer powder is calcium hydroxide powder with a specific surface area of 40 m 2 / g and an average particle size of 30 μm, and the addition amount is Ca / S = 2 in terms of moles. The amino denitration agent is liquid ammonia with a concentration of 100%, and the addition amount is NH3 / NO x = 2.

[0206] The manganese ore is pyrolusite with a manganese content of 18% by mass. Before use, it is calcined at 105 °C for 30 min, and the average volume equivalent diameter is 5 mm. The space velocity in the first removal reactor is 40000 ml / g·h, and the gas residence time is 2 s; the space velocity in the second removal reactor is 30000 ml / g·h, and the gas residence time is 3 s.

[0207] After integrated removal, in the gas discharged from the outlet of the second removal reactor: SO2 is 3 mg / m 3 , NO x is 30 mg / m 3 , VOCs is 30 mg / m 3 .

[0208] Industrial Applicability

[0209] The systems and methods of the present invention can be widely used for the treatment of various flue gases in industries such as coking and iron and steel industries, for example.

Claims

1. A method for integrated removal of sulfur oxides, nitrogen oxides and volatile organic compounds from flue gas, characterized in that: The following steps are involved: Pre-desulfurization: The flue gas is brought into contact with the desulfurizer powder to obtain pre-desulfurized flue gas; Mixed ammonia: Mix the pre-desulfurized flue gas with the amino denitrifier to obtain mixed ammonia gas; Integrated removal: The mixed ammonia gas is brought into countercurrent contact with the multi-component removal agent in the integrated removal device; The multi-component remover comprises manganese ore, and the manganese ore is one or more selected from pyrolusite, psilomelane, manganese ore, brown manganese ore, hausmannite, and rhodochrosite.

2. The method according to claim 1, characterized in that The desulfurizing agent powder is one or more selected from baking soda, sodium hydroxide, calcium hydroxide, and magnesium hydroxide; The amino denitrifier is one or more selected from liquid ammonia, aqueous ammonia, and aqueous urea solution; The manganese ore is pretreated manganese ore, and the pretreatment is calcination at 100-400°C; The average volume equivalent diameter of the manganese ore is 0.5 mm to 10 mm.

3. The method according to claim 1, characterized in that The content of sulfur oxides in the flue gas is 1000 mg / m 3 The following; in the pre-desulfurization step, the temperature of the flue gas is 180 to 400°C; in the integrated removal step, the temperature of the mixed ammonia gas is 180 to 400°C, and the countercurrent contact time is 2 to 8s.

4. The method according to claim 1, characterized in that The multi-component stripping agent further comprises inert particles, which do not undergo physical and chemical changes at a temperature of 180 to 400° C. Preferably, the inert particles are one or more selected from ceramic particles, high temperature resistant glass particles, and stainless steel particles; the inert particles are one or more of spherical and rod-shaped; and the average volume equivalent diameter of the inert particles is 5 to 30 mm.

5. The method according to claim 1, characterized in that The following steps are also included: Manganese ore regeneration: washing the manganese ore after the integrated removal step, and then calcining at 100-400°C to obtain regenerated manganese ore; Manganese sulfate recovery: The wastewater generated by water washing in the manganese ore regeneration step is subjected to solid-liquid separation, and then the liquid phase obtained by the solid-liquid separation is evaporated and crystallized to obtain a product containing manganese sulfate.

6. A system for the method according to any one of claims 1 to 5, characterized in that: It includes a pre-desulfurization device, an ammonia mixing device and an integrated removal device, wherein The pre-desulfurization device comprises a pre-desulfurization reactor and a desulfurizer powder injector. The pre-desulfurization reactor has a flue gas inlet and a pre-desulfurization flue gas outlet. The desulfurizer powder injector is configured to inject desulfurizer powder into the pre-desulfurization reactor. The ammonia mixing device comprises an ammonia mixing reactor and an amino denitrification agent injector. The ammonia mixing reactor has a pre-desulfurized flue gas inlet and an ammonia mixing gas outlet. The amino denitrification agent injector is configured to inject the amino denitrification agent into the ammonia mixing reactor. The integrated removal device includes one removal reactor or two removal reactors connected in series, each of which has a gas inlet, a gas outlet, a multi-component removal agent inlet and a multi-component removal agent outlet. A porous plate is arranged between the ammonia mixing device and the integrated removal device.

7. The system according to claim 6, characterized in that The integrated removal device includes two removal reactors connected in series, and the two removal reactors connected in series are connected in the following manner: the gas outlet of the first removal reactor is connected to the gas inlet of the second removal reactor, and the multi-component removal agent inlet of the first removal reactor is connected to the multi-component removal agent outlet of the second removal reactor.

8. The system according to claim 6 or 7, characterized in that: The removal reactors are each independently a moving bed reactor, a fixed bed reactor, a fluidized bed reactor or a spouted bed reactor. Preferably, the outside of the removal reactor has a heat preservation device or the removal reactor is composed of a heat preservation material. More preferably, the removal reactor has a metal lining and an outer layer composed of a heat preservation material.

9. The system according to claim 6, characterized in that The porous plate has a plurality of through holes, and the diameter of the holes is 0.5 mm to 5 mm; preferably, the surface of the porous plate is made of corrosion-resistant material.

10. The system according to claim 6, characterized in that Also included is a manganese ore regeneration unit and an optional manganese sulfate recovery unit, wherein The manganese ore regeneration device comprises a water washing reactor and a calcining reactor, wherein the water washing reactor is configured to wash the manganese ore in the multi-component removal agent discharged from the integrated removal device, and the calcining reactor is configured to calcine the washed manganese ore; The manganese sulfate recovery device includes a solid-liquid separator and an evaporation crystallizer. The solid-liquid separator is configured to perform solid-liquid separation on the wastewater generated in the water washing reactor, and the evaporation crystallizer is configured to perform evaporation crystallization on the liquid phase discharged from the solid-liquid separator.

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