CN114250092A - System and method for reducing emission of low-concentration combustible gas - Google Patents
System and method for reducing emission of low-concentration combustible gas Download PDFInfo
- Publication number
- CN114250092A CN114250092A CN202210030942.9A CN202210030942A CN114250092A CN 114250092 A CN114250092 A CN 114250092A CN 202210030942 A CN202210030942 A CN 202210030942A CN 114250092 A CN114250092 A CN 114250092A
- Authority
- CN
- China
- Prior art keywords
- gas
- fluidized bed
- bed reactor
- catalytic oxidation
- catalyst
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
- C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
- C10L3/06—Natural gas; Synthetic natural gas obtained by processes not covered by C10G, C10K3/02 or C10K3/04
- C10L3/10—Working-up natural gas or synthetic natural gas
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10K—PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLE GASES CONTAINING CARBON MONOXIDE
- C10K1/00—Purifying combustible gases containing carbon monoxide
- C10K1/34—Purifying combustible gases containing carbon monoxide by catalytic conversion of impurities to more readily removable materials
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Combustion & Propulsion (AREA)
- Environmental & Geological Engineering (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Biomedical Technology (AREA)
- Health & Medical Sciences (AREA)
- Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
Abstract
The invention relates to a system and a method for reducing emission of low-concentration combustible gas, comprising a gas heat exchange unit and a catalytic oxidation unit; the gas heat exchange unit comprises a gas heat exchanger, and the gas heat exchanger comprises a first gas channel for untreated gas to enter and pass through and a second gas channel for treated gas to pass through and discharge; the catalytic oxidation unit comprises a fluidized bed reactor, and the fluidized bed reactor is used for carrying out catalytic oxidation reaction on the combustible gas; the outlet of the first gas channel is connected with the gas inlet of the catalytic oxidation unit, and the gas outlet of the catalytic oxidation unit is connected with the inlet of the second gas channel. The invention adopts the means of strengthening heat and mass transfer in the fluidization process and ensuring the heat balance of the system through gas-gas heat exchange and catalytic oxidation, thereby realizing the purpose of reducing the emission of low-concentration combustible gas.
Description
Technical Field
The invention belongs to the technical field of industrial process waste gas purification, and particularly relates to a system and a method for reducing emission of low-concentration combustible gas.
Background
The tail gas discharged by many industrial processes contains low-concentration combustible gas, such as coal mine ventilation (the gas content is less than 1%), lime kiln tail flue gas (the CO content is less than 1%), tail gas discharged by the coking industry (the VOC content is less than 0.1%), and the like. The direct discharge of these combustible gases not only wastes fuel resources, but also causes environmental pollution.
A common method for industrially treating tail gas containing combustible gas is combustion, however, for tail gas containing a low concentration of combustible gas such as those listed above, direct combustion treatment is difficult because of its low calorific value. To achieve the abatement of these low-concentration combustible gases, a common method in the industry includes: high-temperature treatment and medium-low temperature catalytic oxidation.
For example, patent document 1 discloses a process for purifying an exhaust gas containing hydrogen sulfide and organic sulfur, in which the exhaust gas is preheated by a heat storage body, then enters a catalytic oxidation reactor to undergo an oxidation reaction, and a high-temperature gas after the catalytic oxidation reaction passes through the heat storage body.
Cited documents:
patent document 1: CN 112999843A;
patent document 2: CN 107433127A.
Disclosure of Invention
Problems to be solved by the invention
The method of patent document 1 uses a heat accumulator for heat exchange, and its heat exchange capacity is restricted by the capacity of the heat accumulator, and thus it is difficult to use for the treatment of a large air volume gas, and the document does not mention a specific kind of catalytic oxidation reactor bed thereof.
The process of patent document 2 is complicated and the total combustible component content in the gas to be treated is still high, and the economy of treatment using this process is greatly reduced for a combustible gas of a lower concentration.
In the prior art, the method for treating the tail gas containing low-concentration combustible gas requires a high-temperature environment, so that the method is limited by whether high-temperature equipment is arranged near the emission site; the medium-low temperature catalytic oxidation method mostly adopts a catalytic oxidation self-heating method to ensure that the temperature is at the catalyst reaction temperature, and mostly adopts a scheme of heat storage and cold air heating to reduce the influence of heat carried by exhaust gas on the energy balance of the system.
Therefore, it is urgently needed to develop a system and a method for reducing emission of low-concentration combustible gas with large air volume, high efficiency and low cost.
Means for solving the problems
The invention provides a system and a method for reducing emission of low-concentration combustible gas, which adopt a fluidization process to strengthen heat transfer and mass transfer and gas-gas heat exchange to ensure the heat balance of the system and a catalytic oxidation means, thereby realizing the purpose of reducing emission of low-concentration combustible gas.
Specifically, the present invention solves the problems of the present invention by the following means.
[1] A system for abating low concentration combustible gas, comprising: comprises a gas heat exchange unit and a catalytic oxidation unit;
the gas heat exchange unit comprises a gas heat exchanger, and the gas heat exchanger comprises a first gas channel for untreated gas to enter and pass through and a second gas channel for treated gas to pass through and discharge;
the catalytic oxidation unit comprises a fluidized bed reactor, and the fluidized bed reactor is used for carrying out catalytic oxidation reaction on the combustible gas;
the outlet of the first gas channel is connected with the gas inlet of the catalytic oxidation unit, and the gas outlet of the catalytic oxidation unit is connected with the inlet of the second gas channel.
[2] The system according to [1], wherein the catalytic oxidation unit further comprises a catalyst feeder and a discharger connected to the fluidized-bed reactor.
[3] The system according to [1] or [2], characterized in that the catalytic oxidation unit further comprises a fuel feeder connected with the fluidized bed reactor, and the fluidized bed reactor is internally provided with a heat exchange device.
[4] The system according to [1] or [2], characterized in that the fluidized-bed reactor is externally provided with a heat-insulating device or is composed of a refractory heat-insulating material, and preferably, the fluidized-bed reactor is provided with a metal inner liner and an outer layer composed of a heat-insulating material.
[5] The system according to the item [1] or the item [2], characterized in that a gas-solid separation device is further arranged between the gas outlet of the catalytic oxidation unit and the inlet of the second gas channel, the feed inlet of the gas-solid separation device is connected with the gas outlet of the catalytic oxidation unit, the gas outlet of the gas-solid separation device is connected with the inlet of the second gas channel, and the solid outlet of the gas-solid separation device is connected with the fluidized bed reactor.
[6] The system according to [1] or [2], wherein the gas heat exchanger is a tubular heat exchanger or a rotary heat exchanger, and the fluidized bed reactor is a bubbling bed or a circulating fluidized bed.
[7] The system according to item [1] or [2], wherein the gas introduction rate is 200,000Nm3/h or more, and the system resistance is 7000Pa or less.
[8] A method for reducing emission of low-concentration combustible gas is characterized by comprising the following steps:
sending untreated gas containing combustible gas into a gas heat exchange unit for heating to obtain gas after temperature rise;
feeding the heated gas into a fluidized bed reactor, so that combustible gas in the fluidized bed reactor is oxidized in the presence of a catalyst and converted into treated hot gas; and
the treated hot gas is sent into a gas heat exchange unit and is discharged after heat exchange;
wherein the content of combustible gas in the untreated gas is 3% or less.
[9] The method according to [8], wherein the combustible gas is one or more selected from methane, carbon monoxide, hydrogen and other combustible volatile organic compounds; the catalyst is granular and contains one or more of iron, manganese, copper, cobalt, nickel, cerium and zirconium.
[10] The method of [8], further comprising one or more of the following steps:
adding a catalyst into the fluidized bed reactor and discharging the deactivated catalyst from the fluidized bed reactor;
adding fuel into the fluidized bed reactor; and
heat is removed from the fluidized bed reactor.
ADVANTAGEOUS EFFECTS OF INVENTION
The invention has the following advantages and beneficial effects:
compared with a honeycomb or stacked particle catalysis method, the invention strengthens the mass transfer and reaction of gas particles by adopting a fluidization method, has the advantages of low resistance and high efficiency, is suitable for treating large-air-volume gas, and can effectively avoid the deposition of dust in the treated gas and reduce the problem of carbon deposition on the surface of a catalyst because the particles frequently collide and rub in a fluidization reactor.
Secondly, by arranging the gas heat exchanger, the purpose of heating the treated gas can be realized, meanwhile, the maximum utilization of heat in the system is realized, the energy consumption of the system operation is reduced, and the cost is saved.
The catalyst feeder and the discharger are arranged, so that catalyst particles in the reactor can be added or discharged at any time during operation, the system disclosed by the invention is suitable for low-cost catalyst raw materials, even cheap and easily available wastes, and the operation cost of the system is reduced.
And fourthly, the heat exchanger is arranged in the reactor, so that the control of the catalytic reaction temperature can be realized, and the thermal insulation link of the reactor ensures the thermal balance of the fluidized bed reactor.
Drawings
FIG. 1 is a schematic diagram of one embodiment of a system of the present invention.
Description of the reference numerals
1-a gas heat exchanger; 2-a fluidized bed reactor; 3-a catalyst feeder; 4-a fuel charger; 5-a discharger; 6-a heat exchanger; 7-gas-solid separator.
Detailed Description
The present invention will be described in detail below. The technical features described below are explained based on typical embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples.
< terms and definitions >
In the present specification, "emission reduction" means that the amount of a component described in an exhaust gas is reduced;
in the present specification, "low-concentration combustible gas" means that the content of combustible gas is 3% or less.
In the present specification, the numerical range represented by "numerical value a to numerical value B" means a range including the end point numerical value A, B.
In the present specification, the numerical ranges indicated by "above" or "below" mean the numerical ranges including the numbers.
In the present specification, the meaning of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.
As used herein, the use of "optionally" or "optional" means that certain materials, components, performance steps, application conditions, and the like are used or not used.
In the present specification, the unit names used are all international standard unit names, and if not specifically stated, "%" used indicates volume percentage.
Reference throughout this specification to "a preferred embodiment," "an embodiment," and so forth, means that a particular element (e.g., feature, structure, property, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.
< System >
One of the purposes of the invention is to provide a system for reducing emission of low-concentration combustible gas, which comprises a gas heat exchange unit and a catalytic oxidation unit;
the gas heat exchange unit comprises a gas heat exchanger, and the gas heat exchanger comprises a first gas channel for untreated gas to enter and pass through and a second gas channel for treated gas to pass through and discharge;
the catalytic oxidation unit comprises a fluidized bed reactor, and the fluidized bed reactor is used for performing catalytic oxidation on the combustible gas;
the outlet of the first gas channel is connected with the gas inlet of the catalytic oxidation unit, and the gas outlet of the catalytic oxidation unit is connected with the inlet of the second gas channel.
The various components of the system of the present invention are described in detail below.
Gas heat exchange unit
In the system of the present invention, the gas heat exchange unit is configured to heat exchange the untreated gas with the treated gas that has undergone catalytic oxidation, so that the untreated gas is heated while the treated gas that has undergone catalytic oxidation is cooled.
The system of the invention is designed by the gas heat exchange unit, thereby utilizing the heat in the system to the maximum extent. Compared with the mode of using a heat accumulator in the prior art, the mode of directly exchanging heat of the two gases in the heat exchange unit can realize the treatment of the gas with large air volume without the limit of the capacity of the heat accumulator.
The gas heat exchange unit comprises a gas heat exchanger, and the gas heat exchanger comprises a first gas channel and a second gas channel; the outlet of the first gas channel is connected with the gas inlet of the catalytic oxidation unit, and the gas outlet of the catalytic oxidation unit is connected with the inlet of the second gas channel. The first gas channel is used for allowing untreated gas to enter and pass through, the second gas channel is used for allowing treated gas to pass through and discharge, and heat is conducted from the treated gas with higher temperature to the untreated gas with lower temperature. The gases in the first and second gas channels may be heat exchanged in parallel or counter-current flow.
In one embodiment, the gas heat exchanger is a tubular heat exchanger or a rotary heat exchanger.
Catalytic oxidation unit
In the system, the catalytic oxidation unit is configured to oxidize combustible gas in untreated gas in the presence of a catalyst so as to achieve the purpose of reducing emission of the combustible gas.
In the system of the present invention, the catalytic oxidation unit includes a fluidized bed reactor in which the gas to be treated is catalytically oxidized in contact with catalyst particles. According to the invention, by adopting the fluidized bed reactor, on one hand, the mass transfer and reaction between the gas and the catalyst particles are strengthened, and the fluidized bed reactor has the advantages of low resistance and high efficiency, and can realize the treatment of the gas with large air volume, on the other hand, in the fluidized bed reactor, the particles frequently collide and rub, so that the deposition of dust in the treated gas can be effectively avoided, and the problem of carbon deposition on the surface of the catalyst can be reduced.
The present invention is not particularly limited with respect to a specific fluidized bed reactor, and may be any fluidized bed reactor known in the art, such as a bubbling bed or a circulating fluidized bed, and the like.
In one embodiment, the catalytic oxidation unit further comprises a catalyst feeder and a discharger connected to the fluidized bed reactor. Catalyst particles are added into the fluidized bed reactor through a catalyst feeder and are recycled in the fluidized bed reactor, and deactivated catalyst particles are discharged out of the fluidized bed reactor from a discharger. In the embodiment, the catalyst feeder and the discharger are arranged, so that the catalyst particles in the reactor can be added or discharged at any time during the operation, the system disclosed by the invention can be suitable for low-cost catalyst raw materials, and even cheap and easily available wastes can be used as the catalyst, so that the operation cost of the system is reduced.
Examples of the waste usable as the catalyst in the system of the present invention include waste metals such as waste copper slag, steel slag, and manganese slag.
In one embodiment, the catalytic oxidation unit further comprises a fuel feeder connected to the fluidized bed reactor, and the fluidized bed reactor has a heat exchange means inside. When the temperature in the fluidized bed reactor is lower than the action temperature of the catalyst, the fuel is supplemented from the fuel feeder, so that the temperature in the reactor is suitable for the catalyst to catalyze and oxidize low-concentration combustible gas; when the temperature in the fluidized bed reactor is higher than the action temperature of the catalyst, the heat is discharged through a heat exchange device in the fluidized bed reactor. In this embodiment, the temperature of the catalytic reaction can be further controlled by the arrangement of the fuel feeder and the heat exchange device.
In one embodiment, the fluidized bed reactor has insulation external to it or is constructed of refractory insulation. For example, a fluidized bed reactor may have a metal inner liner and an outer layer of insulation. The fluidized bed reactor is insulated, so that the heat balance in the fluidized bed reactor is facilitated, the input of external heat is reduced or avoided, and the running cost of the system is reduced as much as possible.
The present invention is not particularly limited with respect to specific insulating materials, which may be any insulating material known in the art suitable for use in reactors, including, but not limited to, ceramics, mineral wool (e.g., glass wool), and polymer foams, among others.
In one embodiment, a gas-solid separation device is further arranged between the gas outlet of the catalytic oxidation unit and the inlet of the second gas channel, the feed inlet of the gas-solid separation device is connected with the gas outlet of the catalytic oxidation unit, the gas outlet of the gas-solid separation device is connected with the inlet of the second gas channel, and the solid outlet of the gas-solid separation device is connected with the fluidized bed reactor. The gas-solid separation device is arranged for separating catalyst particles entrained in the gas leaving the catalytic oxidation unit and sending the separated catalyst particles back to the catalytic oxidation unit. The design can avoid the loss of the catalyst on one hand, and can prevent solid particles from being entrained in the treated gas and discharged together to form particle pollutants on the other hand.
The system of the invention is suitable for treating large-air-volume gas with the gas inlet speed of 200,000Nm3More than h, preferably 300,000Nm3More preferably 400,000 Nm/h or more3More than h.
The system of the invention has a low system resistance of 7000Pa or less, preferably 6000Pa or less. The "system resistance" refers to a pressure difference between the process gas and the reaction system.
The system of the present invention is further described below in conjunction with the appended figures.
As shown in fig. 1, the system of the present invention includes a gas heat exchanger 1, a fluidized bed reactor 2, a catalyst feeder 3, a fuel feeder 4, a discharger 5, a heat exchanger 6, and a gas-solid separator 7, wherein an outlet of a first gas passage of the gas heat exchanger 1 is connected to a gas inlet of the fluidized bed reactor 2, a gas outlet of the fluidized bed reactor 2 is connected to an inlet of the gas-solid separator 7, a gas outlet of the gas-solid separator 7 is connected to an inlet of a second passage of the gas heat exchanger 1, a solid outlet of the gas-solid separator 7 is connected to the fluidized bed reactor 2, the catalyst feeder 3, the fuel feeder 4, and the discharger 5 are connected to the fluidized bed reactor 2, and the heat exchanger 6 is located inside the fluidized bed reactor 2.
< method >
One of the purposes of the invention is to provide a method for reducing emission of low-concentration combustible gas, which comprises the following steps:
sending untreated gas containing combustible gas into a gas heat exchange unit for heating to obtain gas after temperature rise;
feeding the heated gas into a fluidized bed reactor, so that combustible gas in the fluidized bed reactor is oxidized in the presence of a catalyst and converted into treated hot gas;
the treated hot gas is sent into a gas heat exchange unit and is discharged after heat exchange;
optionally feeding catalyst to the fluidized bed reactor and discharging deactivated catalyst from the fluidized bed reactor;
optionally adding fuel to the fluidized bed reactor; and
optionally removing heat from the fluidized bed reactor;
wherein the content of combustible gas in the untreated gas is 3% or less.
In the method, untreated gas and treated hot gas are subjected to heat exchange, so that the aim of fully utilizing reaction heat is fulfilled, the input of external heat is reduced as far as possible, and the energy consumption and the cost are reduced. By using the fluidized bed reactor for catalytic oxidation, gas can be fully contacted with catalyst particles, the oxidation rate of combustible gas is improved, and emission reduction of the combustible gas is realized as far as possible.
In one embodiment, the method of the invention can be carried out using the system of the invention described above, in which embodiment the preferences and corresponding effects described for the system of the invention apply equally to the method of the invention.
In one embodiment, the process of the present invention comprises the steps of feeding a catalyst into a fluidized bed reactor, and discharging the deactivated catalyst from the fluidized bed reactor. Through the step, the catalyst in the fluidized bed reactor can be updated as required, so that the catalytic efficiency is ensured.
In one embodiment, the process of the present invention comprises the step of adding fuel to a fluidized bed reactor. When the temperature in the fluidized bed reactor is too low, the fuel is added into the fluidized bed reactor, so that the temperature can be maintained in the range of the action temperature of the catalyst, and the efficiency of catalytic oxidation is ensured.
In the present specification, the "catalyst action temperature" refers to a temperature at which the catalyst can exert a catalytic action. The catalyst action temperature may vary for different catalyst systems or for different combustible gas components, for example the catalyst action temperature for each catalyst listed herein may be in the range of 80 to 400 ℃ for the treatment of carbon monoxide containing gases and 300 to 800 ℃ for the treatment of methane containing gases.
In one embodiment, the process of the present invention comprises the step of removing heat from within the fluidized bed reactor, in which embodiment the removed heat is optionally conveyed to a gas heat exchanger. When the temperature of the fluidized bed reactor is too high, the carbon deposition and high-temperature inactivation of the catalyst are avoided by removing the heat.
In the present invention, the temperature in the fluidized bed reactor can be specifically selected depending on the catalyst used and the gas to be treated. In one embodiment, the untreated gas is a low-methane-concentration-containing gas, the waste copper slag is used as a catalyst, and the temperature in the fluidized bed reactor (the temperature of the gas in the fluidized bed reactor) is controlled to be 300 to 580 ℃, for example, 350 to 550 ℃, or 400 to 500 ℃.
In one embodiment, the combustible gas is one or more selected from methane, carbon monoxide, hydrogen and other combustible volatile organics. The content of combustible gas in the untreated gas is 3% or less, preferably 2% or less, and more preferably 1% or less. The other components of the gas to be treated, other than the combustible gas, are non-combustible gases, such as one or more of inert gases, carbon dioxide, oxygen, nitrogen oxides, sulfur oxides, and the like.
In one embodiment, the catalyst is in the form of particles and contains one or more selected from iron, manganese, copper, cobalt, nickel, cerium, and zirconium. The catalyst may be waste, such as waste copper slag, steel slag, manganese slag, etc., in view of cost reduction.
In the method, the oxidation rate of the combustible gas is more than 80 percent, even more than 90 percent, and the content of the combustible gas in the treated gas reaches the standard of direct discharge.
The method of the present invention is further described below in conjunction with the appended figures.
As shown in fig. 1, sending untreated gas into a gas heat exchanger 1, and exchanging heat with treated hot gas to form heated gas; feeding the heated gas into a fluidized bed reactor 2 for catalytic oxidation, carrying out gas-solid separation on the material discharged from the fluidized bed reactor 2 through a gas-solid separator 7, feeding the obtained treated hot gas into a gas heat exchanger 1, and feeding the solid separated from the gas-solid separator 7 back into the fluidized bed reactor 2 for continuous use; the catalyst is fed into the fluidized bed reactor 2 through a catalyst feeder 3, and the inactivated catalyst is discharged through a discharger 5; when the temperature in the fluidized-bed reactor 2 is lower than the lower limit of the catalyst action temperature, the fuel is replenished from the fuel feeder 4; when the temperature in the fluidized-bed reactor 2 is above the upper limit of the catalyst action temperature, heat is removed by means of a heat exchanger 6 in the fluidized-bed reactor.
The invention accordingly relates to the use of a system according to the invention or of a method according to the invention for reducing emissions of combustible gases, for example for treating coal mine ventilation, lime kiln tail gas, tail gas from the coking industry, etc.
The present invention will be further described below by way of specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, it should be understood that various changes or modifications can be made by those skilled in the art after reading the description of the present invention, and such equivalents also fall within the scope of the invention.
Example 1
The untreated gas was coal mine ventilation with a treat rate of 430,000Nm3The methane concentration is 0.8 percent, a circulating fluidized bed reactor is adopted, and the catalyst material is waste copper slag. The gas heat exchanger adopts a rotary heat exchanger. The untreated gas at a temperature of 25 ℃ is sent into a gas heat exchanger to exchange heat with the treated hot gas at a temperature of 450 ℃ to form a heated gas with a temperature of about 410 ℃. After the temperature is raised, the gas enters a circulating fluidized bed reactor. Catalyst particles are added through a catalyst feeder and recycled in the reactor, and waste catalyst particles are discharged out of the system from a discharger. After the temperature is raised, the low-concentration methane in the gas isThe catalyst particles are oxidized under the catalytic action and release heat, and the gas is converted into treated hot gas after the temperature is raised. When the temperature in the reactor is 600 ℃, the temperature is higher than the catalyst action temperature, so that the heat is discharged through a heat exchanger in the reactor, and the temperature of the hot gas after treatment is reduced to 450 ℃. And the treated hot gas enters a gas heat exchanger to exchange heat with untreated gas and is discharged out of the whole system. The methane oxidation rate reaches 90%, and the whole system resistance is 5500 Pa.
The above description is only an example of the present invention, and is not intended to limit the present invention, and it is obvious to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention
Industrial applicability
The system and method of the present invention can be used extensively to abate combustible gases, such as in treating coal mine ventilation.
Claims (10)
1. A system for abating low concentration combustible gas, comprising: comprises a gas heat exchange unit and a catalytic oxidation unit;
the gas heat exchange unit comprises a gas heat exchanger, and the gas heat exchanger comprises a first gas channel for untreated gas to enter and pass through and a second gas channel for treated gas to pass through and discharge;
the catalytic oxidation unit comprises a fluidized bed reactor, and the fluidized bed reactor is used for carrying out catalytic oxidation reaction on the combustible gas;
the outlet of the first gas channel is connected with the gas inlet of the catalytic oxidation unit, and the gas outlet of the catalytic oxidation unit is connected with the inlet of the second gas channel.
2. The system of claim 1, wherein the catalytic oxidation unit further comprises a catalyst loader and a discharger coupled to the fluidized bed reactor.
3. The system of claim 1 or 2, wherein the catalytic oxidation unit further comprises a fuel feeder connected to the fluidized bed reactor, and the fluidized bed reactor has a heat exchange device therein.
4. The system according to claim 1 or 2, characterized in that the fluidized bed reactor is externally provided with insulation or is made of refractory insulation, preferably has a metal inner lining and an outer layer made of insulation.
5. The system according to claim 1 or 2, wherein a gas-solid separation device is further arranged between the gas outlet of the catalytic oxidation unit and the inlet of the second gas passage, the feed inlet of the gas-solid separation device is connected with the gas outlet of the catalytic oxidation unit, the gas outlet of the gas-solid separation device is connected with the inlet of the second gas passage, and the solid outlet of the gas-solid separation device is connected with the fluidized bed reactor.
6. The system according to claim 1 or 2, wherein the gas heat exchanger is a tubular heat exchanger or a rotary heat exchanger and the fluidized bed reactor is a bubbling bed or a circulating fluidized bed.
7. A system according to claim 1 or 2, characterised in that the gas introduction rate is 200,000Nm3More than/h and less than 7000Pa of system resistance.
8. A method for reducing emission of low-concentration combustible gas is characterized by comprising the following steps:
sending untreated gas containing combustible gas into a gas heat exchange unit for heating to obtain gas after temperature rise;
feeding the heated gas into a fluidized bed reactor, so that combustible gas in the fluidized bed reactor is oxidized in the presence of a catalyst and converted into treated hot gas; and
the treated hot gas is sent into a gas heat exchange unit and is discharged after heat exchange;
wherein the content of combustible gas in the untreated gas is 3% or less.
9. The method of claim 8, wherein the combustible gas is one or more selected from the group consisting of methane, carbon monoxide, hydrogen, and other combustible volatile organics; the catalyst is granular and contains one or more of iron, manganese, copper, cobalt, nickel, cerium and zirconium.
10. The method of claim 8, further comprising one or more of the following steps:
adding a catalyst into the fluidized bed reactor and discharging the deactivated catalyst from the fluidized bed reactor;
adding fuel into the fluidized bed reactor; and
heat is removed from the fluidized bed reactor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210030942.9A CN114250092B (en) | 2022-01-12 | 2022-01-12 | System and method for reducing emission of low-concentration combustible gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210030942.9A CN114250092B (en) | 2022-01-12 | 2022-01-12 | System and method for reducing emission of low-concentration combustible gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114250092A true CN114250092A (en) | 2022-03-29 |
| CN114250092B CN114250092B (en) | 2023-04-25 |
Family
ID=80796425
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210030942.9A Active CN114250092B (en) | 2022-01-12 | 2022-01-12 | System and method for reducing emission of low-concentration combustible gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114250092B (en) |
Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0237217A1 (en) * | 1986-03-07 | 1987-09-16 | The BOC Group plc | Treatment of gases |
| CA2026943A1 (en) * | 1989-10-05 | 1991-04-06 | Tsutomu Shikada | Catalytic oxidation of ammonia |
| US20040208810A1 (en) * | 2001-06-21 | 2004-10-21 | Pekka Simell | Method for the purification of gasification gas |
| US20070092436A1 (en) * | 2005-09-21 | 2007-04-26 | Alexandre Rojey | Process for producing synthesis gas by steam reforming in a reactor-exchanger |
| CN101097060A (en) * | 2006-06-30 | 2008-01-02 | 中国科学院工程热物理研究所 | Coal firing method with low discharged nitrous oxides |
| CN101817716A (en) * | 2009-02-27 | 2010-09-01 | 中国科学院过程工程研究所 | Method and device for catalyzing methanation of synthesis gas |
| CN101995016A (en) * | 2010-10-19 | 2011-03-30 | 重庆大学 | Circulating fluidized bed boiler device using low calorific value coal gangue for post ignition |
| CN102133540A (en) * | 2011-01-14 | 2011-07-27 | 清华大学 | Catalyst and method for preparing high-octane fuel through catalytic conversion of alcohol ether |
| CN102517109A (en) * | 2011-12-02 | 2012-06-27 | 中国科学院山西煤炭化学研究所 | Fluidized bed catalytic deoxidation method and equipment for oxygen-containing coal bed gas |
| CN102626590A (en) * | 2011-07-18 | 2012-08-08 | 西南化工研究设计院 | Low-concentration organic combustible gas catalytic oxidation device and heat utilization system |
| CN102950033A (en) * | 2011-08-31 | 2013-03-06 | 中国石油化工股份有限公司 | Method and apparatus for rapidly stabilizing catalyst activity by heavy fuel oil |
| CN102966945A (en) * | 2012-11-02 | 2013-03-13 | 阳光凯迪新能源集团有限公司 | Method for reducing nitrogen oxide discharge of biomass circulating fluid bed boiler |
| CN110368810A (en) * | 2019-08-07 | 2019-10-25 | 清华大学 | A kind of system and method for recirculating fluidized bed light catalytic purifying flue gas |
| CN111735071A (en) * | 2020-07-14 | 2020-10-02 | 江苏南方涂装环保股份有限公司 | Circulating fluidized bed catalytic combustion system for treating organic waste gas |
| CN111853834A (en) * | 2020-07-14 | 2020-10-30 | 江苏南方涂装环保股份有限公司 | Circulating fluidized bed catalytic combustion method for treating organic waste gas |
-
2022
- 2022-01-12 CN CN202210030942.9A patent/CN114250092B/en active Active
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0237217A1 (en) * | 1986-03-07 | 1987-09-16 | The BOC Group plc | Treatment of gases |
| CA2026943A1 (en) * | 1989-10-05 | 1991-04-06 | Tsutomu Shikada | Catalytic oxidation of ammonia |
| US20040208810A1 (en) * | 2001-06-21 | 2004-10-21 | Pekka Simell | Method for the purification of gasification gas |
| US20070092436A1 (en) * | 2005-09-21 | 2007-04-26 | Alexandre Rojey | Process for producing synthesis gas by steam reforming in a reactor-exchanger |
| CN101097060A (en) * | 2006-06-30 | 2008-01-02 | 中国科学院工程热物理研究所 | Coal firing method with low discharged nitrous oxides |
| CN101817716A (en) * | 2009-02-27 | 2010-09-01 | 中国科学院过程工程研究所 | Method and device for catalyzing methanation of synthesis gas |
| CN101995016A (en) * | 2010-10-19 | 2011-03-30 | 重庆大学 | Circulating fluidized bed boiler device using low calorific value coal gangue for post ignition |
| CN102133540A (en) * | 2011-01-14 | 2011-07-27 | 清华大学 | Catalyst and method for preparing high-octane fuel through catalytic conversion of alcohol ether |
| CN102626590A (en) * | 2011-07-18 | 2012-08-08 | 西南化工研究设计院 | Low-concentration organic combustible gas catalytic oxidation device and heat utilization system |
| CN102950033A (en) * | 2011-08-31 | 2013-03-06 | 中国石油化工股份有限公司 | Method and apparatus for rapidly stabilizing catalyst activity by heavy fuel oil |
| CN102517109A (en) * | 2011-12-02 | 2012-06-27 | 中国科学院山西煤炭化学研究所 | Fluidized bed catalytic deoxidation method and equipment for oxygen-containing coal bed gas |
| CN102966945A (en) * | 2012-11-02 | 2013-03-13 | 阳光凯迪新能源集团有限公司 | Method for reducing nitrogen oxide discharge of biomass circulating fluid bed boiler |
| CN110368810A (en) * | 2019-08-07 | 2019-10-25 | 清华大学 | A kind of system and method for recirculating fluidized bed light catalytic purifying flue gas |
| CN111735071A (en) * | 2020-07-14 | 2020-10-02 | 江苏南方涂装环保股份有限公司 | Circulating fluidized bed catalytic combustion system for treating organic waste gas |
| CN111853834A (en) * | 2020-07-14 | 2020-10-30 | 江苏南方涂装环保股份有限公司 | Circulating fluidized bed catalytic combustion method for treating organic waste gas |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114250092B (en) | 2023-04-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7077878B1 (en) | Method for gasifying organic materials and mixtures of materials | |
| CN101532782B (en) | Sintering gas purifying and waste heat recovering technique | |
| EP2744922B1 (en) | Process for producing direct reduced iron (dri) utilizing gases derived from coal | |
| WO2014159956A1 (en) | Distributing secondary solids in packed moving bed reactors | |
| CN111346605B (en) | Pollutant comprehensive treatment system and method suitable for large-scale coal-fired power plant | |
| CN101544914B (en) | Method and device for thermally desulfurizing by synthesis gas dry method and reclaiming sulfur | |
| CN218523969U (en) | Flue gas treatment system of iron and steel smelting electric furnace | |
| CN112500872A (en) | Method and equipment for low-temperature magnetization treatment of garbage | |
| CN109893997B (en) | Biomass boiler fuel preprocess method, pretreatment unit and denitration method for flue gas | |
| CN114574250A (en) | Method and device for preparing clean synthesis gas through biomass chemical-looping gasification | |
| CN113188129B (en) | Method and device for removing pollutants by organic solid waste pyrolysis coupling chemical chain combustion | |
| CN109735369A (en) | A kind of petroleum coke chemical chain gasification produces the device and method of sulphur | |
| CN209541450U (en) | A kind of comprehensive treatment of sintering flue gas and the system of utilizing | |
| CN102292417A (en) | Systems and methods for processing a catalyst regenerator flue gas | |
| CN114250092B (en) | System and method for reducing emission of low-concentration combustible gas | |
| CN114874818B (en) | Blast furnace gas desulfurizer and preparation method and application thereof | |
| CN208512279U (en) | A kind of coke oven flue gas dirt sulphur nitre integration minimum discharge process unit | |
| EP3019268B1 (en) | Method for ventilation air methane mitigation | |
| CN115950270A (en) | Heating furnace desulfurization and denitrification collaborative carbon monoxide removal system and process | |
| CN202973118U (en) | Circulating fluidized bed incinerator for volatile organic gas | |
| CN102380369B (en) | Method for exchanging heat in regenerating process of flue gas desulfurization and denitrification adsorbent | |
| CN111704136B (en) | Desulfurization and denitrification coal-based active coke one-step preparation equipment and method | |
| JP4108886B2 (en) | Method for reducing nitrogen oxides in cement raw material firing equipment | |
| CN211521606U (en) | Sterpu activation furnace system with stable and controllable furnace temperature | |
| AU750751B2 (en) | Process for the production of iron carbide from iron oxide using external sources of carbon monoxide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |