RU2762836C1 - Multi-process exhaust gas purification system and control method - Google Patents

Abstract

FIELD: gas purification.

SUBSTANCE: group of inventions relates to the field of gas purification technologies and, in particular, to a multi-process waste gas purification system and a control method. The group of inventions reveals a multi-process exhaust gas purification system and a control method, including: providing the sintering process with a centralized desorption subsystem forming an integrated structure with the adsorption subsystem of the sintering process, with the possibility of full circulation of activated carbon between the centralized desorption subsystem and the adsorption subsystem of the sintering process through a conveyor chain without the need for additional conveying devices, as a result, the influence of the transportation process on the operation of the system is reduced while preserving transport resources. The centralized desorption subsystem contains a device for distributing the material. The recovered activated carbon is distributed in the adsorption subsystem of the sintering process using the first material distribution device, and the flow rate of activated carbon in the centralized desorption subsystem is equal to the flow rate of activated carbon in the adsorption subsystem of the sintering process and the adsorption subsystems of the remaining processes. By setting the operating parameters of the feeding device, the unloading device and the material distribution device of the centralized desorption subsystem, precise control of the balanced ratio between the centralized desorption subsystem and the adsorption subsystems on the side of the centralized desorption subsystem is ensured.

EFFECT: group of inventions provides regulation of the balance between a centralized desorption subsystem and a set of adsorption subsystems coordinated with it for purifying waste gases.

12 cl, 7 dwg

Description

FIELD OF INVENTION

[0001] The present invention relates to the field of gas purification technologies, and in particular to a multi-process off-gas purification system and control method.

LEVEL OF TECHNOLOGY

[0002] Waste gases are generated in various processes in the steel industry, for example, sintering, coking, blast furnace production, converter production or steelmaking in electric furnaces, etc. The waste gas generated in each process contains a large amount of pollutants such as dust, SO ₂ , NO _X , etc. Activated carbon flue gas cleaning technology is commonly used in the steel industry to desorb SO ₂ and NO _X in flue gases, thereby providing a clean exhaust gas vent.

[0003] FIG. 1 shows a system for cleaning off gases using activated carbon, which includes: an adsorption subsystem 100 for cleaning off gas and unloading contaminated activated carbon, a desorption subsystem 200 for regenerating contaminated activated carbon and unloading reduced activated carbon, an oxidation subsystem (not shown) for recycling and reuse of SO ₂ and NO _X emissions, as well as two activated carbon conveyors 310 and 320. The adsorption subsystem 100 includes an adsorption column 101, a feed device 102 and an unloading device 103. The desorption subsystem 200 includes a desorption and activation column 201, feeder 202 and discharge device 203. During system operation, activated carbon transported by conveyor 310 enters adsorption tower 101 through feeder 102 and forms a bed of activated carbon in adsorption tower 101, while the raw waste gas containing zag The contaminating substances SO ₂ and NO _X continuously enter the adsorption tower 101 and then into the activated carbon bed, so that SO ₂ and NO _X in the raw exhaust gas are adsorbed by the activated carbon, resulting in a purified exhaust gas at the outlet of the system. The unloading device 103 of the adsorption subsystem 100 operates continuously and unloads the contaminated activated carbon saturated with SO ₂ and NO _X from the adsorption tower 101, and then the contaminated activated carbon is transported to the desorption subsystem 200 by the conveyor 320. The contaminated activated carbon transported by the conveyor 320 is fed to the column for desorption and activation 201 by the supply device 202, where contaminants such as SO ₂ and NO _X , etc. are desorbed from the contaminated activated carbon and the contaminated activated carbon is regenerated. The unloading device 203 unloads the activated carbon recovered in the stripping and activation column 201, and then the conveyor 310 transports the activated carbon to the adsorption subsystem 100 for recirculation.

[0004] A first embodiment of the activated carbon flue gas cleaning system shown in FIG. 1 is as follows: a group of adsorption subsystems and a group of desorption subsystems are provided for each off-gas discharge process, and each pair of adsorption subsystems and desorption subsystems operates simultaneously to purify the contaminated off-gas generated in each process. However, this embodiment has the disadvantage that there are too many desorption subsystems. With significant investments in the desorption subsystem, not only equipment resources are wasted, but also the complexity of process control arises. In view of this disadvantage, in the second embodiment of the system, for each off-gas discharge process, only one group of adsorption subsystems is provided, and also at least one centralized desorption subsystem, for treating contaminated activated carbon in such a concentration that corresponds to part or all of the adsorption columns on the entire plant, so that there is a one-to-one correspondence between the centralized desorption subsystem and the adsorption subsystem.

[0005] In the second embodiment of the system, primarily, the main factors affecting the purification of the exhaust gases are the flow rate of the raw exhaust gas entering the adsorption subsystem, the content of pollutants in the raw exhaust gas, and the circulation rate of the activated carbon stream in the adsorption subsystem. ... For example, when the flow rate of the raw off-gas increases and / or the content of pollutants in the raw off-gas increases, the circulation rate of the activated carbon stream in the adsorption subsystem must be simultaneously quantitatively increased to provide the effect of cleaning the off-gases; otherwise, a phenomenon may occur that the activated carbon is saturated, but a part of the pollutants in the raw exhaust gas is not adsorbed, therefore, the purification effect can be reduced. Therefore, for specialists in this field, it has become an urgent task how to balance the relationship between the circulation rate of the activated carbon flow in the adsorption subsystem and factors such as the flow rate of the raw off-gas.

[0006] Next, the centralized desorption subsystem must regenerate the contaminated activated carbon produced by the plurality of adsorption subsystems in large quantities. However, many adsorption subsystems have different discharge rates for contaminated activated carbon; In addition, contaminated activated carbon processed by a centralized desorption subsystem comes from adsorption subsystems provided for different processes, and factors such as equipment failure and adjustment of the production plan, etc., lead to instability of the amount of activated carbon discharged from the adsorption subsystems of different processes. Therefore, it has also become an urgent problem for those skilled in the art how to regulate the balance between the purification of contaminated activated carbon by a centralized desorption subsystem and the amount of activated carbon discharged by a plurality of adsorption subsystems.

SUMMARY OF THE INVENTION

[0007] Thus, it is an object of the present invention to provide a multi-process flue gas purification system and control method, thereby solving the technical problem of accurately controlling the balance between a centralized desorption subsystem and a plurality of associated adsorption subsystems for purifying the flue gas.

[0008] According to a first aspect of the present invention, there is provided a multi-process flue gas purification system, which includes: a plurality of adsorption subsystems provided for each off-gas discharge process, a centralized desorption subsystem corresponding to the plurality of adsorption subsystems, and a transportation subsystem; wherein the adsorption subsystem includes: an adsorption column, a feed device configured to supply activated carbon to the adsorption column, and an unloading device configured to unload contaminated activated carbon from the adsorption column; the centralized desorption subsystem includes: a desorption and activation column, a feed device configured to supply contaminated activated carbon to the desorption and activation column, and an unloading device configured to discharge the activated carbon from the desorption and activation column;

[0009] A centralized desorption subsystem is provided for the sintering process;

[0010] The centralized desorption subsystem further includes:

[0011] A material distribution device that at least includes a first material distribution device configured to distribute activated carbon in the adsorption subsystem of the sintering process, and a second material distribution device configured to distribute the remaining activated carbon in the adsorption subsystems of the remaining processes; and

[0012] Conveyor chain for transporting contaminated activated carbon discharged from the adsorption subsystem of the sintering process to the intermediate tank of the upper part of the column of the centralized desorption subsystem, as well as for transporting the reduced activated carbon distributed by the first material distribution device to the intermediate tank of the upper part of the column of the subsystem adsorption sintering process.

[0013] According to the first aspect, in the first possible embodiment of the first aspect, the centralized desorption subsystem further includes:

[0014] A container for contaminated activated carbon and a first unloading device, wherein the container for contaminated activated carbon is configured to store contaminated activated carbon discharged from the adsorption subsystem, and the first unloading device is configured to unload contaminated activated carbon from the container for contaminated activated carbon onto conveyor at the bottom of the column.

[0015] According to the first aspect or the first possible embodiment of the first aspect, the centralized desorption subsystem further includes:

[0016] A vibrating sieve, which is located under the unloading device of the desorption subsystem and is designed to screen the spent activated carbon from the recovered activated carbon;

[0017] An additional container for activated carbon and a second unloading device, wherein an additional container for activated carbon and a second unloading device are located above the container for contaminated activated carbon, and the second unloading device is configured to unload activated carbon from the additional container into a container for contaminated activated carbon ...

[0018] In a second aspect, a method for controlling a multi-process flue gas cleaning system according to a first aspect of the present invention is provided, which includes:

[0019] Determining the flow rate of activated carbon in real time in the adsorption subsystem matched to the centralized desorption subsystem;

[0020] Determination of the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment based on the flow rate of activated carbon in each adsorption subsystem at time t _i , where the difference from time t _i to the current moment is the time required for contaminated activated carbon for circulation from each adsorption subsystem to the centralized desorption subsystem;

[0021] Setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem depending on the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time, and setting the operating parameters of the first material distributor and the second material distributor based on the flow rate of the activated coal in the adsorption subsystem of the sintering process at time t _i , to control the waste gas cleaning system.

[0022] According to an embodiment of the present invention, in the aforementioned multi-process flue gas purification system, a centralized desorption subsystem is provided for the sintering process, forming an integrated structure with the adsorption subsystem of the sintering process, so that activated carbon circulating between the centralized desorption subsystem and the adsorption subsystem of the sintering process can complete circulation along the conveyor chain without the need for an additional transportation device, thereby reducing the impact of the transportation process on the functioning of the system while conserving transportation resources. Also according to an embodiment of the present invention, a material distribution device is provided in the centralized desorption subsystem, wherein the activated carbon is distributed in the adsorption subsystem of the sintering process by the first material distribution device. The flow rate of activated carbon in the desorption subsystem is balanced with the consumption of the adsorption subsystem of the sintering process and other adsorption subsystems. By setting the operating parameters of the feeding device, the unloading device and the material distribution device of the centralized desorption subsystem, it is possible to precisely control the balanced ratio between the centralized desorption subsystem and the adsorption subsystems from the side of the centralized desorption subsystem.

[0023] According to a second aspect, in a first possible embodiment of the second aspect, the real-time flow rate of activated carbon in an adsorption subsystem matched to a centralized desorption subsystem is determined in steps:

[0024] Determining the flow rate of the raw off-gas entering the adsorption subsystem and the content of pollutants in the off-gas;

[0025] Determining the amount of emission of pollutants in the raw off-gas based on the flow rate of the raw off-gas and the content of the pollutants in the off-gas; and

[0026] Determining the theoretical flow rate of activated carbon in the adsorption subsystem as a function of the flow rate of contaminants in the raw off-gas and determining the theoretical flow rate of activated carbon in the adsorption subsystem in real time.

[0027] Since the flow rate of the raw off-gas and the content of pollutants in the off-gas vary from time to time, in this embodiment of the present invention, the real-time flow rate of activated carbon in each adsorption subsystem is determined depending on the flow rate of the raw off-gas entering to each adsorption subsystem, and also, depending on the content of pollutants in the exhaust gas, in this way, not only the cleaning effect of the exhaust gas can be ensured, but also the reserves of activated carbon are preserved.

[0028] According to the first possible embodiment of the second aspect, in the second possible embodiment of the second aspect, the emission amount of pollutants in the raw flue gas is calculated based on the flow rate of the raw flue gas and the content of the pollutants in the flue gas by the formula:

[0029]

[0030]

[0031] where Q _{Si (t)} is the volume of emission of the pollutant SO ₂ in the raw exhaust gas entering each adsorption subsystem, kg / h;

[0032] C _{Si (t)} is the content of the pollutant SO ₂ in the crude exhaust gas entering the adsorption subsystem, mg / Nm3;

[0033] Q _M ( _t ) is the volume of emission of the pollutant NO _X in the raw exhaust gas entering each adsorption subsystem, kg / h;

[0034] C _{m (t)} is the content of the pollutant NO _X in the crude exhaust gas entering the adsorption subsystem, mg / Nm3;

[0035] V _{i (t)} the flow rate of the crude off-gas entering the adsorption subsystem, Nm3 / h; and

[0036] i is the sequence number of the process to which the adsorption subsystem belongs;

[0037] The theoretical flow rate of activated carbon in the adsorption subsystem is determined based on the amount of pollutants emitted in the raw off-gas using the following formula:

[0038]

[0039] where Q _Xi is the theoretical flow rate of activated carbon in the adsorption subsystem, kg / h; and

[0040] K ₁ is a constant whose value is in the range of 15 ~ 21; K ₂ is a constant, usually in the range 3 ~ 4.

[0041] According to this embodiment of the present invention, the flow rate of activated carbon in each adsorption subsystem in real time can be accurately and quantitatively calculated based on the flow rate of the raw off-gas and the content of pollutants in the off-gas, thereby providing a database for precise control of the waste gas cleaning system.

[0042] According to a second embodiment of the second aspect, in a third possible embodiment of the second aspect, the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem is currently determined based on the consumption of activated carbon in the adsorption subsystem at time t _i by the formula:

[0043]

[0044]

[0045] where Q _X0current is the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment, kg / h;

[0046] Q _{Xi (ti)} is the flow rate of activated carbon in the adsorption subsystem, matched with the centralized desorption subsystem at time t _i , kg / h;

[0047] G _{X1 (ti)} is the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i , kg / h; and

[0048] Q _X1current is the circulation rate of the activated carbon flow in the adsorption subsystem of the sintering process at the current moment, kg / h.

[0049] According to this embodiment, the time t _{i of} each adsorption subsystem corresponding to the current moment is determined by a technically competent calculation of the time it takes to circulate the contaminated activated carbon from each adsorption subsystem to the centralized desorption subsystem, and the theoretical balanced flow rate of activated carbon in the centralized the desorption subsystem at the current time is precisely determined based on the consumption of activated carbon in each adsorption subsystem at the time t _i . Since a centralized desorption subsystem is provided during the sintering process, the time required for contaminated activated carbon to circulate from the adsorption subsystem of the sintering process to the centralized desorption subsystem is 0, therefore, the time t ₁ coincides with the current moment.

[0050] According to the second possible embodiment of the second aspect, in the fourth possible embodiment of the second aspect, the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem are set based on the theoretical balanced rate of the activated carbon in the centralized desorption subsystem at the current time, in steps:

[0051] Determining the theoretical speed of the feeding device and the unloading device of the centralized desorption subsystem as a function of the theoretical balanced consumption of activated carbon in the centralized desorption subsystem at the current time;

[0052] Determining the theoretical operating frequency of the feeding device and the discharging device based on the theoretical speed of the feeding device and the discharging device; and

[0053] Setting the target frequency of the feeder and discharger based on the theoretical operating frequency of the feeder and discharger.

[0054] According to this embodiment, by setting the preset frequency of the feeding device and the discharge device of the centralized desorption subsystem, it is possible to accurately control the balanced ratio between the centralized desorption subsystem and the adsorption subsystems from the side of the centralized desorption subsystem, ensuring ease of operation, easy implementation and high reliability.

[0055] According to the fourth possible embodiment of the second aspect, in the fifth possible embodiment of the second aspect, the theoretical speed of the feeding device and the unloading device of the centralized desorption subsystem is determined by the formula:

[0056]

- теоретическая скорость устройства подачи подсистемы десорбции, кг / час;[0057] where

- theoretical speed of the desorption subsystem feed device, kg / h;

- теоретическая скорость устройства выгрузки подсистемы десорбции, кг / час; и[0058]

- theoretical speed of the device for unloading the desorption subsystem, kg / h; and

[0059] j is a constant whose value is in the range of 0.9 ~ 0.97; also

[0060] The theoretical operating frequency of the feeding device and the discharging device is determined by the formula:

[0061]

[0062]

- теоретическая рабочая частота устройства подачи централизованной подсистемы десорбции;[0063] where

- theoretical operating frequency of the feeding device of the centralized desorption subsystem;

- теоретическую рабочую частоту устройства выгрузки централизованной десорбционной подсистемы; и[0064]

- theoretical operating frequency of the unloading device of the centralized desorption subsystem; and

и

- являются константами, в единицах кг / (ч ⋅ Гц).[0065]

and

- are constants, in units of kg / (h ⋅ Hz).

[0066] Using this embodiment of the present invention, based on the quantitative relationship between the theoretical operating frequency and the theoretical speed of the feeding device and the discharging device, the theoretical operating frequency can be accurately calculated based on the theoretical flow rate. By adjusting the set operating frequency of the feeder and discharger in accordance with the theoretical operating frequency, it becomes possible to control the feed rate and discharge rate of the centralized desorption subsystem devices, thereby providing precise control of the off-gas purification.

[0067] According to the fifth possible embodiment of the second aspect, in the sixth possible embodiment of the second aspect, the operating parameters of the first material distributing device and the second material distributing device are set based on the consumption of activated carbon in the adsorption subsystem of the sintering process at time ti in steps:

[0068] Determining the speed of the first material distributor according to the formula

[0069] Determining the theoretical operating frequency of the first material distributor as a function of the speed of distributing the material by the first material distributor;

[0070] Setting the target frequency of the first material distributor in accordance with the theoretical operating frequency of the first material distributor; and

[0071] Setting the maximum value of the target frequency of the second material distributor;

[0072] In this case, Q _{distribute1 (t)} is the material flow rate of the first material distributor, kg / h.

[0073] By using this embodiment, based on the quantitative relationship between the theoretical operating frequency of the first material distributor and its material distribution speed, this frequency is determined in accordance with the theoretical operating frequency. By adjusting the target frequency of the first material distributor according to the theoretical operating frequency, the flow rate of the activated carbon in the adsorption subsystem of the sintering process can be controlled, and at the same time, by setting the maximum frequency of the second material distributor, calculation and control are simplified, and stable operation is ensured. waste gas cleaning systems.

[0074] According to a second aspect, in a seventh possible embodiment of the second aspect, the method further comprises:

[0075] Setting the operating parameters of the feeding device and the unloading device of the adsorption subsystem in accordance with the theoretical flow rate of activated carbon in the adsorption subsystem for precise control of each adsorption subsystem.

[0076] In a third aspect of the invention, there is disclosed a method for controlling a multi-process flue gas cleaning system that is described in a first possible embodiment of the first aspect, which includes:

[0077] Determining the flow rate of activated carbon in real time in the adsorption subsystem matched with the centralized desorption subsystem;

[0078] Determination of the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment based on the flow rate of activated carbon in each adsorption subsystem at time ti, where the difference from time ti to the current moment is the time it takes contaminated activated carbon to circulate from each adsorption subsystem to a centralized desorption subsystem;

[0079] Setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the moment;

[0080] Setting the operating parameters of the first material distribution device and the second material distribution device in accordance with the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i ; as well as

[0081] Setting the operating parameters of the first unloading device in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time and the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i , to control the exhaust gas cleaning system.

[0082] In a fourth aspect of the present invention, there is disclosed a method for controlling a multi-process flue gas cleaning system in accordance with a second possible embodiment of the first aspect of the invention, which includes:

[0083] Determining the flow rate of activated carbon in real time in the adsorption subsystem corresponding to the centralized desorption subsystem;

[0084] Determination of the theoretically balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment based on the flow rate of activated carbon in each adsorption subsystem at time t _i , where the time difference from time t _i to the current moment is the time it takes contaminated activated carbon for circulation from each adsorption subsystem to a centralized desorption subsystem;

[0085] Setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the moment;

[0086] Setting the operating parameters of the first material distribution device and the second material distribution device in accordance with the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i ; as well as

[0087] Setting the operating parameters of the second unloading device in accordance with the flow rate of the spent activated carbon, which is sieved through the vibrating sieve, to control the waste gas cleaning system.

[0088] From the above technical solutions, it is obvious that in the multi-process off-gas purification system and control method according to the invention, a centralized desorption subsystem is provided for the sintering process, forming an integrated structure with the adsorption subsystem of the sintering process, so that the activated carbon circulating between The centralized desorption subsystem and the adsorption subsystem of the sintering process can complete the circulation along the conveyor chain without the need for an additional transport device, thereby reducing the impact of the transportation process on the functioning of the system while conserving transport resources. A material distribution device is provided in the centralized desorption subsystem, and the reduced activated carbon is distributed to the adsorption subsystem of the sintering process through the first material distribution device, and the flow rate of activated carbon in the centralized desorption subsystem is balanced with the consumption of activated carbon of the adsorption subsystem of the sintering process and the adsorption subsystems of the remaining processes. By setting the operating parameters of the feeding device, the unloading device and the material distribution device of the centralized desorption subsystem, the balanced ratio between the centralized desorption subsystem and the adsorption subsystems on the side of the centralized desorption subsystem is precisely controlled.

BRIEF DESCRIPTION OF DRAWINGS

[0089] To more clearly explain the technical solution of the invention, the drawings required in the embodiments will be briefly described below. Obviously, the drawings in the description below are only some embodiments of the invention, and other drawings may also be obtained by a person skilled in the art according to these drawings.

[0090] FIG. 1 is a structural representation of a prior art activated carbon flue gas purification device.

[0091] FIG. 2 is a structural representation of a prior art multi-process off-gas purification system.

[0092] FIG. 3 is a structural representation of a multi-process flue gas cleaning system according to an embodiment of the invention.

[0093] FIG. 4 is a flow chart of a method for controlling a multi-process flue gas cleaning system in accordance with an embodiment of the invention.

[0094] FIG. 5 is a flow diagram of a method for controlling a multi-process flue gas cleaning system in accordance with a preferred embodiment of the invention.

[0095] FIG. 6 is a flow chart of a method for controlling a multi-process flue gas cleaning system in accordance with another preferred embodiment of the invention.

[0096] FIG. 7 is a flow chart of a method for controlling a multi-process flue gas cleaning system in accordance with another preferred embodiment of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0097] Examples of embodiments that are shown in the drawings will be described in detail herein. In the case where the description below is given with reference to the drawings, the same reference number in the various drawings represents the same or a similar element, unless otherwise indicated. The embodiments described in the following embodiments are not intended to represent all possible embodiments consistent with the present invention. However, they are only examples of an apparatus and a method in accordance with some aspects of the present invention, as detailed in the appended claims.

[0098] FIG. 2 shows a multi-process waste gas cleaning system. As shown in FIG. 2, the off-gas cleaning system includes:

[0099] A plurality of adsorption subsystems (110/120/130, etc.) that are provided for each off-gas removal process by a centralized desorption subsystem 200 matched to the plurality of adsorption subsystems and a transportation subsystem (not shown); contaminated activated carbon discharged from each adsorption subsystem is conveyed to a centralized desorption subsystem for centralized activation; so there is a one-to-one correspondence between the centralized desorption subsystem and each adsorption subsystem in the off-gas treatment system group.

[00100] The centralized desorption subsystem 200 includes: a desorption and activation column 201, a feed device 202 configured to supply contaminated activated carbon to a desorption column 201 and activate, an unloading device 203 configured to discharge activated carbon with restored adsorption capacity , from the stripping and activation column 201, and a conveyor 204 configured to transport contaminated activated carbon from the bottom of the column to the top. According to the present invention, each adsorption subsystem includes an adsorption tower 111, a feed device 112 configured to supply recovered activated carbon to an adsorption tower 111, a discharge device 113 configured to discharge contaminated activated carbon from an adsorption tower 111, a conveyor 114 configured with the possibility of transporting the reduced activated carbon from the lower part of the column to the upper part, a container 115 for storing the reduced activated carbon, as well as an unloading device provided for it

[00101] During system operation, on the side of the adsorption subsystem, activated carbon (which can be replenished with additional activated carbon) is continuously supplied to the intermediate vessel 117 and then to the absorption tower 111 by the feeding device 112; activated carbon is fed into the adsorption tower 111 from top to bottom, while adsorbing the pollutant of the raw off-gas, and finally discharged from the adsorption tower 111 through the unloading device 113. The contaminated activated carbon discharged from the adsorption subsystem is transported towards the centralized desorption subsystem 200 by a conveyor For some adsorption subsystems located far from the centralized desorption subsystem, the contaminated activated carbon is transported using a special transport device.

[00102] On the side of the centralized desorption subsystem 200, contaminated activated carbon from a plurality of adsorption subsystems is transported by a conveyor 204 to an intermediate vessel at the top of the stripper from the bottom, and then fed via a feeder 202 to a stripper 201 for regeneration. After the contaminated activated carbon has reached the bottom of the column, it is discharged by the unloading device 203 and then fed via a transport subsystem to the adsorption subsystem of any process for reuse.

[00103] According to the system of FIG. 2, the invention is a multi-process waste gas purification system. As shown in FIG. 3, in the multi-process off-gas cleaning system according to the present invention, a centralized desorption subsystem 200 is provided for the sintering process.

[00104] The centralized desorption subsystem 200 further includes:

[00105] A material distribution device 212, which at least includes: a first material distribution device 2121 configured to distribute the recovered activated carbon in the adsorption subsystem 110 of the sintering process, and a second material distribution device 2122 configured to distribute the remaining recovered activated carbon in the adsorption subsystems of the remaining processes; as well as

[00106] Conveyor chain for transporting the contaminated activated carbon discharged from the adsorption subsystem 110 of the sintering process to the intermediate tank of the upper part of the column of the centralized desorption subsystem 200 and for transporting the reduced activated carbon distributed by the first material distribution device 2121 to the intermediate tank of the upper part of the column subsystems of adsorption of the sintering process.

[00107] Referring to FIG. 3, the conveyor chain comprises a first conveyor 210 and a second conveyor 211.

[00108] In fact, in the steel industry, the amount of off-gas generated in the sintering process is about 70% of the total amount of off-gas generated in the steel industry, which means that the amount of activated carbon required for the adsorption subsystem of the sintering process is relatively maximum. Considering the above, a centralized desorption subsystem is provided for the sintering process, and the centralized desorption subsystem forms an integrated structure with the adsorption subsystem of the sintering process. The activated carbon circulating between the centralized desorption subsystem and the adsorption subsystem of the sintering process can complete the circulation along the conveyor chain without the need for an additional conveying device, thereby reducing the effect of the conveying process on the functioning of the system while conserving transport resources.

[00109] After the inclusion of the centralized desorption subsystem in the sintering process, a large amount of raw off-gas obtained from the sintering process enters the adsorption subsystem 110 of the sintering process through a tube. Contaminated activated carbon discharged from the adsorption subsystem 110 of the sintering process is directly fed to the centralized desorption subsystem 200 by the conveyor 210, and the activated carbon discharged from the centralized desorption subsystem is directly fed to the adsorption subsystem 110 of the sintering process by the conveyor

[00110] In addition, the centralized desorption subsystem comprises a material dispenser 212, which includes a first material dispenser 2121 and a second material dispenser 2122. The recovered activated carbon required by the adsorption subsystem 110 of the sintering process may be pre-dispensed by the first material dispenser 2121 and is directly discharged onto conveyor 211, and then delivered by conveyor 211 to the top of the adsorption subsystem column of the sintering process - for feeding, which is equivalent to internal recirculation. At the same time, the recovered activated carbon discharged by the second material distributor 2122 is accordingly transported to the adsorption subsystems in the remaining processes by the conveying subsystem, which is equivalent to external recirculation.

[00111] In some preferred embodiments of the invention, the centralized desorption subsystem 200 further includes:

[00112] Container 205 for contaminated activated carbon and a first unloading device 206, wherein the container 205 for contaminated activated carbon is configured to store contaminated activated carbon discharged from the adsorption subsystem, and the first unloading device 206 is configured to unload contaminated activated carbon from the container for contaminated activated carbon to the second conveyor 211.

[00113] In some other preferred embodiments of the present invention, the centralized desorption subsystem 200 further includes:

[00114] Vibrating sieve 209, which is located below the discharge device 203 of the centralized desorption subsystem 200 and is designed to separate the spent activated carbon from the recovered activated carbon;

[00115] An additional container 207 for activated carbon and a second unloading device, moreover, an additional container for activated carbon and a second unloading device 208, which are located above the container 205 for contaminated activated carbon, and the second unloading device 208 is configured to unload activated carbon from the additional container 207 into a container 205 for contaminated activated carbon.

[00116] It should be noted that the additional activated carbon is intended to replenish the consumption of activated carbon generated during the circulation or during the adsorption process, and to control the circulation rate of the activated carbon stream in the centralized desorption subsystem.

[00117] During operation of the flue gas cleaning system shown in FIG. 3, on the side of the centralized desorption subsystem 200, contaminated activated carbon from a plurality of adsorption subsystems may be temporarily stored in the contaminated activated carbon container 205. The contaminated activated carbon can be discharged from the tank 205 onto the conveyor 210 at a certain speed by the first discharge device 206. At the same time, the contaminated activated carbon discharged from the adsorption subsystem 110 of the sintering process is directly discharged onto the conveyor 210 and then transported to the conveyor 210 from the bottom columns to the intermediate tank of the upper part of the stripping column. Contaminated activated carbon is fed by a feeder 202 to a stripper 201 for regeneration. After the spent activated carbon reaches the bottom of the column, it is discharged by the unloading device 203 and then transported by the transport subsystem to the adsorption subsystem of each process for reuse. In practice, during the operation of the system, the loss of activated carbon is inevitable. In the present invention, the spent activated carbon which is finely divided is sieved by the vibrating sieve 209, and at the same time new activated carbon is supplied to the system.

[00118] According to the present invention, activated carbon is circulated between the adsorption subsystem and the centralized desorption subsystem, thus, a plurality of closed loop structures are formed in the exhaust gas purification system. For example, the centralized desorption subsystem 200 and the adsorption subsystem 110 of the sintering process form a closed loop structure, and the centralized desorption subsystem and the adsorption subsystem of the coking process form another closed loop structure.

[00119] Based on this cycle structure, Applicant believes that continuous, stable and efficient operation of the flue gas cleaning system can only be guaranteed if the sum of the activated carbon flow rate of each adsorption subsystem is theoretically equal to the activated carbon flow rate of the centralized desorption subsystem. Through such an equivalence relation, the present invention provides a method for controlling the aforementioned multi-process flue gas purification system, thereby solving the technical problem of precisely controlling the balance between a centralized desorption subsystem and a plurality of associated adsorption subsystems to purify flue gases.

[00120] FIG. 4 is a flow diagram of a control method for a multi-process flue gas cleaning system in accordance with an exemplary embodiment of the invention. It should be noted that the method according to the present invention can be reproduced and executed on a computer. As shown in FIG. 4, the method includes the following steps.

[00121] Step 110: determining the flow rate of activated carbon in real time in the adsorption subsystem matched with the centralized desorption subsystem;

[00122] In the present invention, a group of off-gas cleaning systems includes several adsorption subsystems and one centralized desorption subsystem, with each adsorption subsystem correspondingly equipped with each exhaust gas emission process, for example, during sintering, pelletizing, coking, blast-furnace metallurgical production, converter production or smelting steel in electric furnaces, rolling steel, calcining in a lime kiln, operating a power plant, etc. Since there are different waste gas emission processes in the present invention, the letter i is used to distinguish the adsorption subsystems in different processes, where i denotes the serial number of each process. For example, in the present invention, the sequence number i of the sintering process is 1.

[00123] From the operating process of the above flue gas purification system, it can be seen that the flow rate of the raw flue gas entering the adsorption subsystem, the content of pollutants in the raw flue gas, and the flow rate of activated carbon in the adsorption subsystem are the main factors influencing the effluent purification effect. gases. For example, when the flow rate of the raw off-gas increases and / or the content of contaminants in the raw off-gas increases, the flow rate of the activated carbon in the adsorption subsystem must be quantitatively increased to ensure that the off-gas is cleaned; otherwise, a phenomenon may occur that the activated carbon is adsorbed and a part of the pollutants in the raw exhaust gas is not adsorbed, therefore, the purification effect can be reduced.

[00124] That is, the flow rate of the activated carbon in each adsorption subsystem is not constant. Instead, it changes depending on the flow rate of the raw off-gas and the pollutant content in it, and this change is usually intermittent. For example, the flow rate of activated carbon can be adjusted every second cycle period, without adjusting at other times. In the above step 110, the change in flow rate is monitored by real-time determination of the flow rate of the activated carbon in the adsorption subsystem at different times. For example, the real time flow rate of the adsorption subsystem of the sintering process at 12:00, January 1, 2018 is Q _{X1 (01011200)} , where Q _X1 represents the flow rate of the activated carbon in the adsorption subsystem.

[00125] In addition, it should be noted that in the present invention, the flow rate of the activated carbon in the adsorption subsystem may optionally be controlled by the feeding device or the discharge device of the adsorption subsystem.

[00126] Step 120: The theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time is determined as a function of the flow rate of activated carbon in each adsorption subsystem at time ti, where the difference from time ti to the current time is the time required contaminated activated carbon for circulation from each adsorption subsystem to a centralized desorption subsystem.

[00127] In fact, during operation of a multi-process flue gas cleaning system, the different location of each ejection process results in a different distance between each adsorption subsystem and the centralized desorption subsystem, which means that the time required for contaminated activated carbon discharged by each adsorption subsystem to circulate into a centralized desorption subsystem - different. For ease of understanding, the invention uses Ti to represent the time it takes contaminated activated carbon to circulate from each adsorption subsystem to a centralized desorption subsystem. For example, the time required for contaminated activated carbon to circulate from the adsorption subsystem of the sintering process to the centralized desorption subsystem is T ₁ , and the time required for the contaminated activated carbon to circulate from the adsorption subsystem of the coking process to the centralized desorption subsystem is T ₂ , etc.

[00128] In step 120 of the present invention, the flow rate of activated carbon in the centralized desorption subsystem is determined in accordance with the flow rate of activated carbon in each adsorption subsystem, and the flow rate of activated carbon at time ti in each adsorption subsystem matched to the centralized desorption subsystem is equivalent to theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment. Since the contaminated activated carbon takes a certain amount of time to circulate from each adsorption subsystem to the centralized desorption subsystem, and the Ti corresponding to the other adsorption subsystem is different, in step 120 of the present invention, the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem is currently determined based on the flow rate of activated carbon in each adsorption subsystem at time ti; the difference from the time ti to the current moment is the time required for the contaminated activated carbon to circulate from each adsorption subsystem to the centralized desorption subsystem, that is, Ti = tcurrent-ti.

[00129] Step 130: the operating parameters of the feeding device and the discharge device of the centralized desorption subsystem are set in accordance with the theoretical balanced rate of the activated carbon in the centralized desorption subsystem at the current time, and the operating parameters of the first material distributor and the second material distributor are set depending on the flow rate of active carbon in the adsorption subsystem of the sintering process at time ti, to control the off-gas cleaning system.

[00130] In step 130, by setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem, the practical flow rate of the activated carbon in the centralized desorption subsystem is currently equal to the theoretical balanced coal in each adsorption subsystem corresponding to the centralized desorption subsystem, at time t _i , is compared with the theoretical balanced rate of activated carbon in the centralized desorption subsystem at the current time, thereby providing accurate control of the balanced ratio between the centralized desorption subsystem and the adsorption subsystems on the centralized side desorption subsystems.

[00131] In addition, by setting the operating parameters of the first material distribution device, the flow rate of the activated carbon in the first material distribution device becomes equal to the flow rate of the activated carbon in the adsorption subsystem of the sintering process; also by setting the operating parameters of the second material distributor, the flow rate of the activated carbon in the second material distributor becomes equal to the flow rate of the activated carbon in the other adsorption subsystems except for the adsorption subsystem of the sintering process.

[00132] From the technical concept of the present invention, it is evident that the above step 110 is a key step for the implementation of the present invention, which provides an accurate database for the subsequent control process. In fact, there are various implementations of the above step 110, and one preferred implementation is presented in the present invention in terms of application. As shown in FIG. 5, in a preferred embodiment, the real-time flow rate of the activated carbon in each adsorption subsystem corresponding to the centralized desorption subsystem is determined in the following steps.

[00133] Step 210: the flow rate of the raw off-gas entering the adsorption subsystem and the content of pollutants are determined.

[00134] In fact, in the steel industry, the amount of raw waste gas generated in each off-gas discharge process and the pollutant content of the off-gas are variable, and hence the flow rate of the raw off-gas entering each adsorption subsystem and the pollutant content substances in the waste gases will also vary depending on the process. By presetting the detection device in each adsorption subsystem, data on the raw waste gas flow rate in each adsorption subsystem and the content of pollutants in the waste gas can be collected. In addition, since the flow rate of the raw off-gas entering each adsorption subsystem and the content of pollutants in the off-gas are important factors that affect the purification effect of the off-gas according to the present invention, the flow rate of the raw off-gas entering each adsorption subsystem is and the content of pollutants in the exhaust gases are taken as the main database for controlling the flow rate of activated carbon of each adsorption subsystem.

[00135] In this embodiment of the present invention, on the side of the adsorption subsystem, the flow rate of the activated carbon in each adsorption subsystem is precisely controlled depending on the flow rate of the raw off-gas and the pollutant content of the off-gas, thereby ensuring the purification of the off-gas and efficient use of the activated carbon. ...

[00136] Step 220: The amount of emission of pollutants in the raw off-gas is obtained depending on the flow rate of the raw off-gas and the content of the pollutants in the off-gas.

[00137] At step 220 of the present invention, a preferred calculation method is presented. For example, when the pollutants are SO ₂ and NO _X , the amount of pollutant in the raw flue gas is calculated using the following formula:

[00138]

[00139]

[00140] where Q _{Si (t)} is the volume of emission of the pollutant SO ₂ in the raw exhaust gas entering each adsorption subsystem, kg / h;

[00141] C _{Si (t)} is the content of the pollutant SO ₂ in the crude exhaust gas entering the adsorption subsystem, mg / Nm3;

[00142] Q _{Ni (t)} is the volume of emission of the pollutant NO _X in the raw exhaust gas entering each adsorption subsystem, kg / h;

[00143] C _{M (t)} is the content of the pollutant NO _X in the raw exhaust gas entering the adsorption subsystem, mg / Nm3;

[00144] V _{i (t)} is the flow rate of the crude off-gas entering the adsorption subsystem, Nm3 / h; and

[00145] i is the sequence number of the process to which the adsorption subsystem belongs;

[00146] Step 230: The theoretical activated carbon flow rate in the adsorption subsystem is determined based on the volume of pollutants in the raw off-gas, also the theoretical activated carbon flow rate in the adsorption subsystem is determined as a real-time flow rate.

[00147] At step 230 of the present invention, an exemplary calculation method is presented. For example, when the pollutants are SO ₂ and NO _X , the theoretical flow rate of activated carbon in the adsorption subsystem corresponding to the centralized desorption subsystem is determined by the formula:

[00148]

[00149] where Q _Xi is the theoretical flow rate of activated carbon in the adsorption subsystem, kg / h; and

[00150] K ₁ is a constant whose value is in the range of 15 ~ 21; K ₂ is a constant, usually in the range 3 ~ 4.

[00151] In this embodiment, the theoretical flow rate of activated carbon in each adsorption subsystem is accurately and quantitatively calculated based on the flow rate of the raw off-gas and the content of pollutants in the off-gas, thereby providing a database for precise control of the off-gas cleaning system according to the present invention.

[00152] Based on the above embodiment shown in FIG. 5, in other embodiments of the present invention, the control method further includes:

[00153] Step 140: the operating parameters of the feeding device and the discharge device of each adsorption subsystem are set in accordance with the theoretical flow rate of activated carbon in each adsorption subsystem to ensure precise control of each adsorption subsystem.

[00154] According to the present invention, since a centralized desorption subsystem is provided during the sintering process, the time required for the contaminated activated carbon to circulate from the adsorption subsystem of the sintering process to the centralized desorption subsystem can be as high as 0. Therefore, according to the above embodiment of FIG. 5, in a preferred embodiment of the invention, the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem is currently determined by the following formula:

[00155]

[00156]

[00157] where Q _X0cvrrent is the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time, kg / h;

[00158] Q _{Xi (ti)} is the flow rate of activated carbon in each adsorption subsystem at time ti, kg / h;

[00159] Q _{X1 (ti)} is the flow rate of activated carbon in the adsorption subsystem of the sintering process at time ti, kg / h; and

[00160] Q _X1current is the rate of circulation of the activated carbon flow in the adsorption subsystem during sintering at the current time, kg / h.

[00161] According to this embodiment, the time ti of each adsorption subsystem that corresponds to the current moment is determined by a technically competent calculation of the time required for the circulation of contaminated activated carbon from each adsorption subsystem to the centralized desorption subsystem, and the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem is currently accurately determined based on the flow rate of the activated carbon in each adsorption subsystem at time ti. Since a centralized desorption subsystem is provided during the sintering process, the time required for contaminated activated carbon to circulate from the adsorption subsystem of the sintering process to the centralized desorption subsystem is 0; therefore, the time t1 coincides with the current moment, i.e. t1 = tcurrent.

[00162] According to the present invention, the feeding device, the discharging device and the material distribution device of the centralized desorption subsystem at least include an electric motor and a material transport device driven by an electric motor such as a roller feeder. The electric motor is driven by the frequency converter, and the rotation speed of the electric motor is determined by the operating frequency of the converter, and the speed of material movement by the feeding device, the unloading device and the material distributing device is proportional to the rotation speed of the electric motor.

[00163] Based on this, in the preferred embodiment of the invention, as shown in FIG. 6, the operating parameters of the feeding device and the discharge device of the centralized desorption subsystem are set in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time, in the following steps.

[00164] Step 310: the theoretical speed of the feeding device and the discharging device of the centralized desorption subsystem is determined based on the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the moment;

[00165] In the above step 310, if necessary, the theoretical flow rate of the feeding device and the discharging device of the centralized desorption subsystem is determined by the formula:

[00166]

- теоретическая скорость устройства подачи централизованной подсистемы десорбции, кг / час;[00167] where

- theoretical speed of the feeding device of the centralized desorption subsystem, kg / h;

- теоретическая скорость устройства выгрузки централизованной подсистемы десорбции, кг / час; и[00168]

- theoretical speed of the unloading device of the centralized desorption subsystem, kg / h; and

[00169] j is a constant, usually in the range 0.9 ~ 0.97.

= теоретической скорости потока устройства выгрузки централизованной подсистемы десорбции

= теоретической сбалансированной скорости потока активированного угля в централизованной подсистеме десорбции в текущий момент времени Q_X0(t) × j.[00170] It should be noted that since the contaminated activated carbon is activated carbon that adsorbs a large amount of pollutants, compared to the activated carbon of the same volume, the mass of the contaminated activated carbon will generally be 3% more. -10%, that is, for the same batch of activated carbon, the weight after desorption and activation will be 0.9 ~ 0.97 by weight after adsorption of the pollutant. Based on this, the invention has the following equivalence relation: theoretical speed of the feed device of the centralized desorption subsystem

= theoretical flow rate of the unloading device of the centralized desorption subsystem

= theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time Q _{X0 (t)} × j.

[00171] Step 320: the theoretical operating frequency of the feeding device and the discharging device is determined based on the theoretical speed of the feeding device and the discharging device;

[00172] In the present invention, the feeding device and the discharging device of the centralized desorption subsystem can actually perform the function of feeding and discharging through a material feeding device driven by an electric motor. Since the electric motor is driven by the frequency converter, the speed of the motor is determined by the frequency of the converter, and the feeding speed of the material by the feeding device and the discharging device is proportional to the rotation speed of the electric motor, that is, the operating frequency of the converter of the feeding device and the discharging device is proportional to the speed of the material conveying device. Therefore, if necessary, according to the present invention, the theoretical operating frequency of the feeding device and the discharging device is determined by the formula:

[00173]

[00174]

- теоретическая рабочая частота устройства подачи централизованной подсистемы десорбции;[00175] where

- theoretical operating frequency of the feeding device of the centralized desorption subsystem;

- теоретическая рабочая частота устройства выгрузки централизованной подсистемы десорбции; и[00176]

- theoretical operating frequency of the unloading device of the centralized desorption subsystem; and

и

являются константами, в единицах кг / (ч ⋅ Гц).[00177]

and

are constants, in units of kg / (h ⋅ Hz).

[00178] Step 330: The target frequency of the feeder and discharger is set in accordance with the theoretical operating frequency of the feeder and discharger.

[00179] By setting the target frequency of the feeder and discharger, when the practical operating frequency of the feeder and discharger is equal to the theoretical operating frequency, the circulation rate of the activated carbon stream in the centralized desorption subsystem will be equal to the theoretical balanced activated carbon flow rate, thereby balancing a centralized desorption subsystem and each adsorption subsystem.

[00180] In this embodiment of the present invention, based on the quantitative relationship between the theoretical operating frequency and the theoretical flow rate of the feeding device and the discharging device, the theoretical operating frequency can be accurately calculated in accordance with the theoretical flow rate. By adjusting the operating frequency of the feeder and discharger to the theoretical operating frequency, the feed and discharge rates of the centralized desorption subsystem can be controlled, thereby realizing precise control of the off-gas purification system.

[00181] In the present invention, for the reduced activated carbon discharged from the centralized desorption subsystem, the portion required by each adsorption subsystem is first distributed by the material distributor, and then transported to each adsorption subsystem by the conveying subsystem. In particular, based on the above embodiment, one preferred embodiment of the invention is shown in FIG. 7. In this embodiment, the operating parameters of the first material distributor and the second material distributor are set based on the flow rate of the activated carbon into the adsorption subsystem of the sintering process at time ti in the following steps.

[00182] Step 410: the rate of distribution of the material by the first distributor is determined in accordance with the formula Q _{distribute1 (t)} = Q _{X1 (t)} x j;

[00183] Step 420: The theoretical operating frequency of the first material distributor is determined as a function of the speed of distributing the material by the first distributor;

[00184] Step 430: the predetermined frequency of the first material distributor is set depending on the theoretical operating frequency of the first material distributor, and the predetermined frequency of the second material distributor is set to a maximum value;

[00185] where Q _{distribute1 (t)} is the speed of material distribution by the first distributor, kg / h.

[00186] It should be noted that the above-mentioned first material dispenser and the second material dispenser are material conveying devices driven by an electric motor such as roller feeders. According to the present invention, the material spreading speed of the first distributor and the second material distributor, that is, the material spreading speed of the distributor, is controlled by controlling the operating frequency of the roller feeder.

[00187] The embodiment of FIG. 7 is based on the quantitative relationship between the theoretical operating frequency of the first material spreading device and the material spreading speed. The target frequency is determined in accordance with the theoretical operating frequency, and by adjusting the target frequency of the first material distributor depending on the theoretical operating frequency, the flow rate of the activated carbon in the adsorption subsystem of the sintering process can be controlled; and at the same time, the maximum value of the preset frequency of the second material distribution device is set, as a result of which the calculation and control is simplified, as well as the stable operation of the waste gas cleaning system is ensured.

[00188] By setting the operating parameters of the material distribution device, the reduced activated carbon is distributed in advance, and then the distributed activated carbon is transported to the corresponding adsorption subsystem by the transport subsystem. In this way, transport resources are saved, and at the same time, the space filled with the reduced activated carbon accumulated on the side of the adsorption subsystem can be avoided, whereby an insufficient amount of the reduced activated carbon can affect the operation of the system.

[00189] From the structure, operating principle and workflow of the above multi-process flue gas cleaning system, it is evident that the centralized desorption subsystem 200 further includes a contaminated activated carbon tank 205 for storing contaminated activated carbon, and a first discharge device 206 for controlling unloading speed of contaminated active carbon, located at the bottom of the tank 205.

[00190] Based on this, a method for controlling a multi-process flue gas cleaning system according to an embodiment of the present invention further includes the following steps based on the above steps S110 to S130:

[00191] Setting the operating parameters of the first unloading device in accordance with the theoretical balanced rate of activated carbon in the centralized desorption subsystem at the current time and the flow rate of activated carbon in the adsorption subsystem of the sintering process at time ti.

[00192] In particular, the speed of the first unloading device at the current time is determined by the formula

[00193] Setting the operating parameters of the unloading device in accordance with the speed of the first unloading device;

[00194] where Q _C0current is the speed of the first unloading device at the current moment, kg / h.

[00195] In fact, according to the present invention, the feeder and discharge device of the centralized desorption subsystem are key devices for controlling the flow rate of activated carbon in the centralized desorption subsystem. On this basis, in order to further ensure stable operation of the centralized desorption subsystem, the invention also controls the speed of the first unloading device, so that an underfeed or overfeeding of the centralized desorption subsystem can be avoided.

[00196] Referring to FIG. 4, it should be noted that the centralized desorption subsystem 200 further includes: a vibrating sieve 209, which is located below the desorption subsystem discharge device 203, an additional activated carbon tank 207 and a second discharge device 208 located above the contaminated activated carbon tank 205; wherein the vibrating sieve 209 is designed to screen out the spent activated carbon, and the second unloading device is designed to unload the activated carbon.

[00197] Based on the foregoing, a method for controlling a multi-process flue gas cleaning system according to an embodiment of the present invention further includes the following steps based on steps S110 to S130:

[00198] Setting the operating parameters of the second unloading device in accordance with the flow rate of the spent activated carbon screened by the vibrating sieve.

[00199] Specifically, the flow rate of the additional activated carbon is determined based on the flow rate of the spent activated carbon screened by the vibrating sieve; for example, the consumption of the spent activated carbon is equal to the consumption of additional activated carbon, thereby balancing the feed amount and the discharge volume of the centralized desorption subsystem.

[00200] Setting the operating parameters of the second unloading device depending on the flow rate of the additional activated carbon.

[00201] Finally, in a multi-process flue gas purification system and control method according to embodiments of the present invention, a centralized desorption subsystem is provided during sintering to form an integrated structure with an adsorption subsystem of the sintering process subsystem. The activated carbon circulating between the centralized desorption subsystem and the adsorption subsystem of the sintering process can complete the circulation along the conveyor chain without the need for an additional conveying device, thereby reducing the effect of the conveying process on the functioning of the system while conserving transport resources. A device for material distribution is provided in the centralized desorption subsystem, the reduced activated carbon is distributed in the adsorption subsystem of the sintering process using the first material distribution device, and the flow rate of activated carbon in the centralized desorption subsystem is compared with the flow rate of activated carbon of the adsorption subsystem of the sintering process and the adsorption subsystems of the remaining processes ... By setting the operating parameters of the feeding device, the unloading device and the material distribution device of the centralized desorption subsystem, it is possible to precisely control the balanced ratio between the centralized desorption subsystem and the adsorption subsystems on the side of the centralized desorption subsystem.

[00202] In a specific embodiment of the present invention, a computer storage medium is further provided that contains a program, wherein during execution, the program may implement only part or all of the steps of each embodiment of the control method according to the invention. The storage medium can be a magnetic disk, an optical disk, read only memory (ROM) or random access memory (RAM), etc.

[00203] With the description of the above embodiments of the control method, one skilled in the art can clearly understand that the invention can be implemented with software of the required general purpose hardware platform. On this basis, a substantial part of the technical solutions in the embodiments of the present invention, or in other words, the part that contributes to the prior art, can be embodied in the form of a software product that is stored on a medium, such as a ROM / RAM, a magnetic disk or an optical disk, etc., and includes several instructions that can be used to implement on a computer device (personal computer, server or network device, etc.) all or part of the steps of the method in accordance with each embodiment of the invention.

[00204] For the same or a similar portion, references may be made to each other between embodiments of the invention. More specifically, for an embodiment of the system, since it is substantially the same as the embodiments of the method, its description will be simple, and for the related part, reference may be made to the illustration of the embodiments of the method.

[00205] The above embodiments of the invention will not define the protection scope of the invention.

Claims (70)

1. A multi-process waste gas purification system comprising: a plurality of adsorption subsystems, respectively provided in each off-gas removal process, a centralized desorption subsystem corresponding to a plurality of adsorption subsystems, and a transportation subsystem, the adsorption subsystem comprising: an adsorption column, a feed device capable of supplying activated carbon to the adsorption tower, and a discharge device configured to discharge the contaminated activated carbon from the adsorption tower; the centralized desorption subsystem comprises: a desorption and activation column, a feed device configured to supply contaminated activated carbon to the desorption and activation column, and an unloading device configured to unload the recovered activated carbon from the desorption and activation column; characterized in that the centralized desorption subsystem is provided during the sintering process and the centralized desorption subsystem further comprises: a material distribution device, which at least comprises a first material distribution device configured to distribute the activated carbon to the adsorption subsystem of the sintering process, and a second material distribution device configured to distribute the remaining activated carbon to the adsorption subsystems for the remaining processes; a conveyor capable of transporting contaminated activated carbon discharged from the adsorption subsystem of the sintering process to the intermediate tank of the upper part of the column of the centralized desorption subsystem, and a conveyor capable of transporting the recovered activated carbon distributed by the first material distribution device to the intermediate tank of the upper part of the column sintering process adsorption subsystems; as well as a container configured to store contaminated activated carbon discharged from the remaining adsorption subsystems, and a first device for unloading contaminated activated carbon from said container onto said conveyor configured to transport contaminated activated carbon discharged from the adsorption subsystem of the sintering process. 2. The system according to claim 1, characterized in that the centralized desorption subsystem further comprises a vibrating sieve located below the unloading device of the desorption subsystem and configured to separate the spent activated carbon from the recovered activated carbon; and a container for additional activated carbon and a second unloading device, wherein the container for additional activated carbon and the second unloading device are located above the container for contaminated activated carbon, and the second unloading device is configured to unload activated carbon from the container for additional activated carbon into the container for contaminated activated carbon ... 3. A method for controlling a multi-process waste gas cleaning system according to claim 1, including: determining the flow rate in real time of the activated carbon in the adsorption subsystem corresponding to the centralized desorption subsystem; determination of the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment depending on the flow rate of activated carbon in each adsorption subsystem at time t _i , and the difference from time t _i to the current time is the time required for circulation of the contaminated activated carbon coal from each adsorption subsystem to a centralized desorption subsystem; and setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem depending on the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time and setting the operating parameters of the first material distribution device and the second material distribution device in accordance with the activated carbon flow rate in the subsystem adsorption of the sintering process at time t _i to control the off-gas cleaning system. 4. The method according to claim 3, characterized in that the steps of determining the flow rate of activated carbon in real time in the adsorption subsystem corresponding to the centralized desorption subsystem include: determining the flow rate of the raw off-gas entering the adsorption subsystem and the content of pollutants in the off-gas; determining the amount of emission of pollutants in the raw off-gas depending on the flow rate of the raw off-gas and the content of pollutants in the off-gas; determining the theoretical flow rate of activated carbon in the adsorption subsystem as a function of the flow rate of pollutants in the raw off-gas; and determining the theoretical flow rate of activated carbon in the adsorption subsystem as a real-time flow rate. 5. The method according to claim 4, characterized in that the volume of emission of pollutants in the raw off-gas is calculated based on the value of the flow rate of the raw off-gas and the content of pollutants in the off-gas according to the formula:

where Q _{Si (t)} is the volume of SO ₂ pollutant emission in the raw off-gas entering each adsorption subsystem, kg / h; С _{Si (t)} - the content of the pollutant SO ₂ in the raw off-gas entering the adsorption subsystem, mg / Nm ³ ; Q _{Ni (t)} is the volume of emission of the pollutant NO _X in the raw off-gas entering the adsorption subsystem, kg / h; C _{Ni (t)} - the content of the pollutant NO _X in the raw exhaust gas entering the adsorption subsystem, mg / Nm ³ ; V _{i (t)} is the flow rate of the crude off-gas entering the adsorption subsystem, Nm ³ / h; i is the ordinal number of the process to which the adsorption subsystem belongs; as well as the theoretical flow rate of activated carbon in the adsorption subsystem is determined depending on the consumption of pollutants in the raw exhaust gas by the formula:

where Q _Xi is the theoretical flow rate of activated carbon in the adsorption subsystem, kg / h; K ₁ is a constant, typically in the range of 15 to 21 and K ₂ is a constant, typically in the range of 3 to 4. 6. The method according to claim 5, characterized in that the theoretical balanced consumption of activated carbon in the centralized desorption subsystem is currently determined based on the flow rate of activated carbon in the adsorption subsystem at time t _i according to the formula below:

where

- theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment, kg / h; Q _{Xi (ti)} - flow rate of activated carbon of the adsorption subsystem corresponding to the centralized desorption subsystem at time t _i , kg / h; Q _{X1 (ti)} is the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i , kg / h; and

- the rate of circulation of activated carbon in the adsorption subsystem of the sintering process at the current moment, kg / h. 7. The method according to claim 5 or 6, characterized in that the steps of determining the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem are set in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment, include: determining the theoretical speed of the feeding device and the unloading device of the centralized desorption subsystem in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment; determining the theoretical operating frequency of the feeding device and the discharging device in accordance with the theoretical speed of the feeding device and the discharging device; and setting the target frequency of the feeder and discharger in accordance with the theoretical operating frequency of the feeder and discharger. 8. The method according to claim 7, characterized in that the theoretical speed of the feeding device and the unloading device of the centralized desorption subsystem is determined by the following formula:

where

- theoretical speed of the desorption subsystem feed device, kg / h;

- theoretical speed of the device for unloading the desorption subsystem, kg / h; j is a constant, usually in the range from 0.9 to 0.97; as well as the theoretical operating frequency of the feeding device and the unloading device is determined by the formula:

where

- theoretical operating frequency of the feeding device of the centralized desorption subsystem;

- theoretical operating frequency of the unloading device of the centralized desorption subsystem; and

and

- constants. 9. The method according to claim 8, characterized in that the operating parameters of the first material distribution device and the second material distribution device are set depending on the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i at the stages: determining the flow rate of material distribution in the first material distribution device according to the formula

; determining the theoretical operating frequency of the first material distributor as a function of the flow rate of the first material distributing device; setting a predetermined frequency of the first material distributor based on the theoretical operating frequency of the first material distributing device; as well as setting the maximum value of the predetermined frequency of the second material distribution device; where

- material distribution speed by the first material distribution device, kg / h. 10. The method according to claim 4 or 5, further comprising: setting the operating parameters of the feeding device and the unloading device of the adsorption subsystem in accordance with the theoretical flow rate of activated carbon in the adsorption subsystem to ensure accurate control of each adsorption subsystem. 11. A method for controlling a multi-process waste gas cleaning system according to claim 1, characterized in that it includes: determining the flow rate of activated carbon in real time in the adsorption subsystem corresponding to the centralized desorption subsystem; determination of the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment depending on the flow rate of activated carbon in each adsorption subsystem at time t _i , while the difference from time t _i to the current moment is the time required for circulation of the contaminated activated carbon coal from each adsorption subsystem to a centralized desorption subsystem; setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem based on the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment; setting the operating parameters of the first material distribution device and the second material distribution device based on the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i ; and setting the operating parameters of the first unloading device in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current time and the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i to control the off-gas purification system. 12. A method for controlling a multi-process waste gas cleaning system according to claim 2, characterized in that it includes: determining the flow rate of activated carbon in real time in the adsorption subsystem corresponding to the centralized desorption subsystem; determination of the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment in accordance with the flow rate of activated carbon in each adsorption subsystem at time t _i , while the difference from time t _i to the current time is the time required for circulation of the contaminated activated carbon from each adsorption subsystem to a centralized desorption subsystem; setting the operating parameters of the feeding device and the unloading device of the centralized desorption subsystem in accordance with the theoretical balanced flow rate of activated carbon in the centralized desorption subsystem at the current moment; setting the operating parameters of the first material distribution device and the second material distribution device in accordance with the flow rate of activated carbon in the adsorption subsystem of the sintering process at time t _i ; and setting the operating parameters of the second unloading device in accordance with the flow rate of the spent activated carbon screened by the vibrating sieve to control the off-gas purification system.

Images