Fine desulfurization device and fine desulfurization method for realizing activated carbon regeneration

Abstract

The invention provides a fine desulfurization device for realizing activated carbon regeneration and a blast furnace gas fine desulfurization method. An adsorption tower in the fine desulfurization device firstly adsorbs blast furnace gas to be purified through activated carbon to obtain purified blast furnace gas; then the purified blast furnace gas and converter gas sequentially pass through a heat exchanger and a heater and then are alternately input into an adsorption tower so as to respectively carry out primary regeneration treatment and deep regeneration treatment on the activated carbon, and the reducibility of the converter gas is higher than that of the purified blast furnace gas; the activated carbon can achieve a better regeneration effect at the same regeneration temperature, so that the service life of the activated carbon is effectively prolonged, and the material cost of a fine desulfurization device is further reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of coal gas desulfurization treatment, and in particular to a fine desulfurization device and a fine desulfurization method for realizing activated carbon regeneration. Background Art

[0002] Blast furnace gas is a by-product of the blast furnace ironmaking process. In addition to CO2 (14-18% by mass), CO (24-28% by mass), H2 (1-2% by mass), and N2 (56-60% by mass), it also contains 50-200 mg / Nm 3 The sulfur-containing components of waste gas are mainly organic sulfur (COS and CS2, etc.) and inorganic sulfur (H2S), accounting for approximately 70% and 30% respectively. These sulfur-containing components are burned and converted into SO2 during subsequent use, polluting the environment.

[0003] The current mainstream blast furnace gas desulfurization solution is COS hydrolysis and conversion coupled with H2S removal. This involves first converting the difficult-to-remove COS in the gas into easily removable H2S under the action of a hydrolysis catalyst. H2S is then removed through activated carbon adsorption or alkaline absorption. Activated carbon adsorption is the most widely used method. In most cases, the activated carbon is used once. In a few cases, the adsorbed activated carbon is regenerated in situ through thermal reduction using purified blast furnace gas as a carrier gas. However, this method also suffers from a sharp decrease in the activated carbon's breakthrough sulfur capacity (the percentage of the activated carbon's mass adsorbed by H2S when the activated carbon reaches saturation) with increasing regeneration frequency. This results in a shorter activated carbon lifespan and higher material costs.

[0004] Therefore, it is urgent to develop a fine desulfurization device for realizing activated carbon regeneration and a fine desulfurization method for blast furnace gas to solve the above technical problems. Summary of the Invention

[0005] In view of this, the present application provides a fine desulfurization device and a fine desulfurization method for realizing activated carbon regeneration, so as to solve the technical problem that the fine desulfurization cost of the existing blast furnace gas fine desulfurization device increases sharply due to the short service life of the activated carbon in the adsorption tower.

[0006] The object of the present invention is achieved through the following technical solutions: In order to achieve the above technical objectives, this application adopts the following technical solutions: The present invention provides a fine desulfurization device for achieving activated carbon regeneration, comprising at least two adsorption towers, each loaded with activated carbon, a heat exchanger, and a heater. The heat exchanger, the heater, and any one of the adsorption towers are sequentially connected by pipelines to form a closed loop. The activated carbon in each adsorption tower is used to adsorb blast furnace gas to be purified to obtain purified blast furnace gas. Among them, the cold fluid inlet of the heat exchanger is used to alternately input purified blast furnace gas and converter gas, and the cold fluid outlet of the heat exchanger is connected to the inlet of the heater; the hot fluid inlet of the heat exchanger is connected to multiple adsorption towers, and the hot fluid outlet of the heat exchanger is used to output the analysis gas.

[0007] Preferably, each adsorption tower is connected to a first air inlet pipe, a second air inlet pipe, a first air outlet pipe and a second air outlet pipe, the first air inlet pipe is connected to a first gas storage tank loaded with blast furnace gas to be purified, the second air inlet pipe is connected to the outlet of the heater, the first air outlet pipe is respectively connected to a second gas storage tank loaded with purified blast furnace gas and the cold fluid inlet of the heat exchanger, and the second air outlet pipe is connected to the hot fluid inlet of the heat exchanger.

[0008] Preferably, a first valve is installed on the first air inlet pipe, a second valve is installed on the second air inlet pipe, a third valve and a fourth valve are installed on the first air outlet pipe, and a fifth valve is installed on the second air outlet pipe; Wherein, the second gas storage tank is located between the third valve and the fourth valve.

[0009] Preferably, multiple adsorption towers are connected in parallel.

[0010] Preferably, the fine desulfurization device for realizing activated carbon regeneration also includes a fan and a sixth valve, one end of the fan is connected to the cold fluid inlet of the heat exchanger, the other end of the fan is connected to the second ends of the fourth valve and the sixth valve respectively, and the first end of the sixth valve is connected to the third gas storage tank loaded with converter gas.

[0011] Accordingly, the present invention also provides a fine desulfurization method for achieving activated carbon regeneration, which is applicable to any of the fine desulfurization devices for achieving activated carbon regeneration as described above, and the method comprises: S10, providing a fine desulfurization device, the fine desulfurization device including at least two adsorption towers; S20, inputting the blast furnace gas to be purified into a partial adsorption tower for adsorption treatment to obtain purified blast furnace gas and desorption gas; S30, the mass concentration of H2S in the purified blast furnace gas output from the adsorption tower is greater than or equal to 10 mg / Nm 3 After that, the adsorption tower after the blast furnace gas to be purified is inputted is switched to the regeneration state, and at the same time, the adsorption tower after the blast furnace gas to be purified is not inputted is switched to the adsorption state; S40, returning the purified blast furnace gas to the adsorption tower in the regeneration state for in-situ thermal reduction regeneration treatment, so that the activated carbon in the adsorption tower in the regeneration state is converted into preliminarily regenerated activated carbon; S50, inputting the converter gas into the adsorption tower in the regeneration state for deep thermal reduction regeneration treatment, so that the primary regenerated activated carbon is converted into deep regenerated activated carbon; S60, the mass concentration of H2S in the purified blast furnace gas output by the adsorption tower in the adsorption state is greater than or equal to 10 mg / Nm 3 After that, the adsorption tower which is in the adsorption state at this time is transferred to the regeneration state, and at the same time, the adsorption tower which is in the regeneration state at this time is transferred to the adsorption state; S70, repeating steps S40 to S60 multiple times until the breakthrough sulfur capacity of the activated carbon in the adsorption tower is less than 5%.

[0012] Preferably, in step S20: the volume space velocity of the adsorption treatment is 30 to 3000 h -1 , the temperature is 40~120℃.

[0013] Preferably, in step S40: the volume space velocity of the in-situ thermal reduction regeneration treatment is 5 to 100 h -1 , the regeneration temperature is 200~400℃, and the regeneration time is 24~48h.

[0014] Preferably, in step S50, the volume space velocity of deep thermal reduction regeneration treatment is 5 to 100 h -1 , the regeneration temperature is 200~400℃, and the regeneration time is 24~48h.

[0015] Preferably, before performing step S60, the process further includes: maintaining the space velocity of the adsorption tower in the regeneration state unchanged, returning the purified blast furnace gas to the adsorption tower in the regeneration state for cooling treatment, and cooling the temperature in the adsorption tower in the regeneration state to 40-120°C.

[0016] Beneficial effect: The present invention provides a fine desulfurization device for realizing activated carbon regeneration and a fine desulfurization method for blast furnace gas. The adsorption tower in the above-mentioned fine desulfurization device first uses activated carbon to adsorb the blast furnace gas to be purified to obtain purified blast furnace gas. Thereafter, the purified blast furnace gas and converter gas are alternately input into the adsorption tower after passing through a heat exchanger and a heater in sequence to perform preliminary regeneration treatment and deep regeneration treatment on the activated carbon, respectively. Since the reducing property of converter gas is stronger than that of purified blast furnace gas, it can enable the activated carbon to achieve a better regeneration effect at the same regeneration temperature, thereby effectively extending the service life of the activated carbon and further reducing the material cost of the fine desulfurization device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the overall structure of a fine desulfurization device for achieving activated carbon regeneration provided in an embodiment of the present application; Figure 2 A flow chart of a fine desulfurization method for achieving activated carbon regeneration provided in an embodiment of the present application; Figure 3 A schematic diagram of the overall structure of a fine desulfurization device for achieving activated carbon regeneration provided in Example 1 of the present application; Figure 4 Schematic diagram of the breakthrough sulfur capacity test results of activated carbon in the fine desulfurization device for achieving activated carbon regeneration provided in Example 1 of the present application during multiple cycles of adsorption regeneration under two conditions: simulated converter gas (CO concentration 67%) and simulated blast furnace gas (CO concentration 25%); In the attached figure: 100 - fine desulfurization device; 10 - adsorption tower; 11 - first adsorption tower; 12 - second adsorption tower; 20 - heat exchanger; 30 - heater; 40 - fan; 51 - first valve; 511 - first adsorption inlet valve; 512 - first regeneration inlet valve; 513 - first adsorption outlet valve; 515 - first regeneration outlet valve; 52 - second valve; 521 - second adsorption inlet valve; 522 - second regeneration inlet valve; 523 - second adsorption outlet valve; 525 - second regeneration outlet valve; 53 - third valve; 54 - fourth valve; 55 - fifth valve; 56 - sixth valve. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] Aiming at the technical problem that the cost of fine desulfurization increases sharply due to the short service life of activated carbon in the adsorption tower of the existing blast furnace gas fine desulfurization device, the present invention provides an adsorption tower in the fine desulfurization device for realizing activated carbon regeneration. The adsorption tower firstly adsorbs the blast furnace gas to be purified by activated carbon to obtain purified blast furnace gas. After that, the purified blast furnace gas and converter gas are alternately input into the adsorption tower after passing through a heat exchanger and a heater in sequence to perform preliminary regeneration treatment and deep regeneration treatment on the activated carbon, respectively. Since the reducing property of converter gas is stronger than that of purified blast furnace gas, it can make the activated carbon achieve better regeneration effect at the same regeneration temperature, thereby effectively extending the service life of the activated carbon and further reducing the material cost of the fine desulfurization device.

[0020] See also Figure 1 , Figure 1 Schematic diagram of the overall structure of a fine desulfurization device 100 for achieving activated carbon regeneration provided in an embodiment of the present application; wherein the present invention provides a fine desulfurization device 100 for achieving activated carbon regeneration, comprising at least two adsorption towers 10, each loaded with activated carbon, a heat exchanger 20, and a heater 30. The heat exchanger 20, the heater 30, and any one of the adsorption towers 10 are sequentially connected by pipes to form a closed loop. The activated carbon in each adsorption tower 10 is used to adsorb the blast furnace gas to be purified to obtain purified blast furnace gas. Among them, the cold fluid inlet of the heat exchanger 20 is used to alternately input purified blast furnace gas and converter gas, and the cold fluid outlet of the heat exchanger 20 is connected to the inlet of the heater 30; the hot fluid inlet of the heat exchanger 20 is connected to multiple adsorption towers 10, and the hot fluid outlet of the heat exchanger 20 is used to output the analysis gas.

[0021] In this embodiment of the present invention, multiple adsorption towers 10 are filled with activated carbon. Activated carbon has a highly developed pore structure, which gives it a large specific surface area. Impurities such as hydrogen sulfide (H2S) and chloride ions in blast furnace gas can be physically adsorbed onto the pore surfaces. For example, H2S molecules can undergo van der Waals adsorption on the inner surface of the activated carbon pores, effectively removing them from the blast furnace gas. When blast furnace gas containing chloride ions passes through the activated carbon, the chloride ions are captured by the pores. Some of these chloride ions may also chemically react with functional groups on the activated carbon surface, such as carbon-hydrogen groups, further enhancing the chloride ion removal effect.

[0022] In an embodiment of the present invention, the cold fluid inlet of the heat exchanger 20 is used to alternately input purified blast furnace gas and converter gas, and the cold fluid outlet of the heat exchanger 20 is connected to the inlet of the heater 30; the hot fluid inlet of the heat exchanger 20 is connected to multiple adsorption towers 10, and the hot fluid outlet of the heat exchanger 20 is used to output the analysis gas.

[0023] Specifically, regardless of whether the cold fluid inlet of heat exchanger 20 inputs purified blast furnace gas or converter gas, once it enters the heat exchanger 20 as the cold fluid, it exchanges heat within the heat exchanger 20 with the desorbed gas flowing in from the hot fluid inlet. The desorbed gas, produced during the activated carbon regeneration process in adsorption tower 10, is relatively hot and carries a large amount of heat. Through the efficient heat exchange of heat exchanger 20, the cold fluid (purified blast furnace gas or converter gas) absorbs the heat from the desorbed gas, gradually increasing its temperature. Meanwhile, the desorbed gas, due to the heat transferred to the cold fluid, cools its own temperature, ultimately achieving efficient heat transfer.

[0024] In an embodiment of the present invention, each adsorption tower 10 is connected to a first air inlet pipe, a second air inlet pipe, a first air outlet pipe and a second air outlet pipe. The first air inlet pipe is connected to a first gas storage tank loaded with blast furnace gas to be purified, the second air inlet pipe is connected to the outlet of the heater 30, the first air outlet pipe is respectively connected to the second gas storage tank loaded with purified blast furnace gas and the cold fluid inlet of the heat exchanger 20, and the second air outlet pipe is connected to the hot fluid inlet of the heat exchanger 20.

[0025] Specifically, the first air inlet pipe is connected to the first gas storage tank containing the blast furnace gas to be purified. Its main function is to transport the blast furnace gas to be purified into the adsorption tower 10. The blast furnace gas to be purified starts from the first gas storage tank and enters the adsorption tower 10 along the first air inlet pipe, thereby starting the purification process in the adsorption tower 10 by using activated carbon.

[0026] Specifically, the second air inlet pipe is connected to the outlet of heater 30. During system operation, the gas (which may be blast furnace gas or converter gas, depending on the alternating input) preheated by heat recovery in heat exchanger 20 enters heater 30 for further temperature adjustment before flowing out of heater 30 and into adsorption tower 10 through the second air inlet pipe. This heated gas entering adsorption tower 10 is likely used to regenerate the activated carbon within adsorption tower 10. By providing appropriate temperature and other conditions, impurities previously adsorbed on the activated carbon are desorbed, achieving regeneration of the activated carbon and ensuring that adsorption tower 10 can continuously and stably purify subsequent incoming blast furnace gas.

[0027] Specifically, the first gas outlet pipe has two connections, one leading to the second gas storage tank containing purified blast furnace gas and the other to the cold fluid inlet of heat exchanger 20. On the one hand, the blast furnace gas, after being purified by the activated carbon in adsorption tower 10, flows through the first gas outlet pipe to the second gas storage tank for storage, allowing it to be subsequently delivered to other uses as needed, such as combustion equipment for power generation. On the other hand, a portion of the purified blast furnace gas flows into the cold fluid inlet of heat exchanger 20, where it acts as a cold fluid to exchange heat with the thermal desorption gas flowing out of adsorption tower 10 (which enters the hot fluid inlet of heat exchanger 20 through the second gas outlet pipe), achieving heat recovery and improving the energy efficiency of the entire system.

[0028] Specifically, the second outlet pipe connects the adsorption tower 10 to the hot fluid inlet of the heat exchanger 20. It is primarily responsible for transporting the desorbed gas generated during the activated carbon regeneration process within the adsorption tower 10 to the heat exchanger 20. Within the adsorption tower 10, during activated carbon regeneration, impurities are heated and desorbed, accompanying the gas to form desorbed gas. This desorbed gas carries a certain amount of heat. After entering the heat exchanger 20 through the second outlet pipe, it acts as a hot fluid, transferring heat to the purified blast furnace gas or converter gas, which serves as the cold fluid. After the heat transfer is complete, the desorbed gas is output from the hot fluid outlet of the heat exchanger 20 for subsequent processing.

[0029] In an embodiment of the present invention, a first valve 51 is installed on the first air inlet pipe, a second valve 52 is installed on the second air inlet pipe, a third valve 53 and a fourth valve 54 are installed on the first air outlet pipe, and a fifth valve 55 is installed on the second air outlet pipe; wherein, the second air storage tank is located between the third valve 53 and the fourth valve 54.

[0030] Specifically, the first valve 51 is mainly used to control the on-off and flow rate of the blast furnace gas to be purified from the first gas storage tank into the adsorption tower 10; the second valve 52 is mainly used to control the on-off and flow rate of the hot gas (gas used for activated carbon regeneration) flowing out of the heater 30 and entering the adsorption tower 10, so as to accurately control the flow rate of the hot gas entering the adsorption tower 10 and ensure that the regeneration process can be carried out efficiently and stably; the third valve 53 and the fourth valve 54 work together to control the flow direction and flow rate of the purified blast furnace gas on the first outlet pipe; the main function of the fifth valve 55 is to control the on-off and flow rate of the analysis gas.

[0031] In an embodiment of the present invention, the fine desulfurization device 100 for realizing activated carbon regeneration also includes a fan 40 and a sixth valve 56. One end of the fan 40 is connected to the cold fluid inlet of the heat exchanger 20, and the other end of the fan 40 is connected to the second ends of the fourth valve 54 and the sixth valve 56 respectively. The first end of the sixth valve 56 is connected to the third gas storage tank loaded with converter gas.

[0032] Specifically, fan 40 provides additional power for the gas (purified blast furnace gas or converter gas) entering heat exchanger 20, ensuring smooth and stable flow of gas into heat exchanger 20. This power boost from fan 40 ensures sufficient gas velocity and flow rate for efficient heat exchange, especially in situations where the system faces significant resistance or requires rapid heat exchange. Furthermore, by adjusting parameters such as fan 40's speed and power, operators can precisely control the gas flow rate entering heat exchanger 20, thereby flexibly adjusting the heat exchange efficiency of the entire system and the operation of subsequent related process steps based on actual production needs and the operating status of heat exchanger 20.

[0033] Specifically, the primary function of sixth valve 56 is to control the entry of converter gas into the system. When the system requires the introduction of converter gas into the cooling fluid of heat exchanger 20 for heat exchange, based on production process requirements, comprehensive energy utilization considerations, or different operating conditions, sixth valve 56 is opened, allowing the converter gas to enter the cooling fluid inlet of heat exchanger 20 under the power of fan 40. When converter gas is no longer needed, closing sixth valve 56 blocks the entry of converter gas. This flexible switching mechanism allows the system to rationally select either purified blast furnace gas or converter gas as the cooling fluid based on actual conditions, enhancing the system's adaptability to different gas sources and its energy utilization flexibility.

[0034] In an embodiment of the present invention, multiple adsorption towers 10 are connected in parallel; wherein, multiple adsorption towers 10 are connected in parallel, which means that they can simultaneously carry out adsorption purification work on the blast furnace gas to be purified, or independently perform operations such as activated carbon regeneration at different times.

[0035] See also Figure 2 , Figure 2 A flow chart of a fine desulfurization method for achieving activated carbon regeneration provided in an embodiment of the present application; wherein the fine desulfurization method for achieving activated carbon regeneration is applicable to any of the fine desulfurization devices 100 for achieving activated carbon regeneration as described above, and the method specifically includes: S10, providing a fine desulfurization device 100, the fine desulfurization device 100 includes at least two adsorption towers 10; wherein, the setting of multiple adsorption towers 10 provides a basis for subsequent alternating adsorption and regeneration operations, ensuring that the entire system can operate continuously and stably, and avoiding the interruption of gas treatment due to the adsorption or regeneration process of a single adsorption tower 10.

[0036] S20, inputting the blast furnace gas to be purified into the partial adsorption tower 10 for adsorption treatment to obtain purified blast furnace gas and desorption gas; The blast furnace gas to be purified is fed into the partial adsorption tower 10 for adsorption treatment, a key step in achieving desulfurization. During this process, the activated carbon within the adsorption tower 10 removes sulfur-containing impurities such as hydrogen sulfide (H2S) and other possible contaminants from the blast furnace gas, resulting in purified blast furnace gas and degassing gas.

[0037] S30, the mass concentration of H2S in the purified blast furnace gas output from the adsorption tower 10 is greater than or equal to 10 mg / Nm 3 After that, the adsorption tower 10 after the blast furnace gas to be purified is inputted is switched to the regeneration state, and at the same time, the adsorption tower 10 after the blast furnace gas to be purified is not inputted is switched to the adsorption state; The criterion for determining H2S concentration in the purified blast furnace gas is a concentration of 10 mg / Nm³ or greater. Reaching this concentration indicates that the activated carbon in the adsorption tower 10 currently performing adsorption treatment has decreased in adsorption capacity and is nearing saturation, necessitating regeneration. Simultaneously, any adsorption towers 10 not currently in adsorption operation are switched to adsorption mode, ensuring uninterrupted purification of the blast furnace gas throughout the system and maintaining a stable gas purification process. The adsorption treatment volumetric space velocity is controlled between 30 and 3000 h⁻¹, and the temperature is set between 40 and 120°C. These parameters have been optimized through practical experience. Under these conditions, the activated carbon can effectively absorb impurities and ensure purification results, while also balancing factors such as treatment efficiency and energy consumption.

[0038] S40, returning the purified blast furnace gas to the adsorption tower 10 in the regeneration state for in-situ thermal reduction regeneration treatment, so that the activated carbon in the adsorption tower 10 in the regeneration state is converted into preliminarily regenerated activated carbon; The purified blast furnace gas is returned to the regenerating adsorption tower 10 for in-situ thermal reduction regeneration, converting the activated carbon in the adsorption tower 10 into preliminarily regenerated activated carbon. During this process, the volumetric space velocity is controlled at 5-100 h⁻¹, the regeneration temperature is set at 200-400°C, and the regeneration time is 24-48 hours. These parameters are designed to effectively desorb impurities such as sulfur adsorbed on the activated carbon under appropriate reaction conditions, achieving initial regeneration and restoring a certain level of adsorption capacity. Excessively high or low parameters are also designed to prevent adverse effects on the activated carbon structure and regeneration performance.

[0039] S50, inputting the converter gas into the adsorption tower 10 in the regeneration state for deep thermal reduction regeneration treatment, so that the primary regenerated activated carbon is converted into deep regenerated activated carbon; Here, converter gas is introduced into the regenerating adsorption tower 10 for deep thermal reduction regeneration, further converting the preliminarily regenerated activated carbon into deeply regenerated activated carbon. Similarly, parameters such as volumetric space velocity, regeneration temperature, and regeneration time are similar to those in step S40. This indicates that at this stage, it is necessary to further remove residual impurities from the activated carbon under relatively stable and appropriate conditions, improve the regeneration quality of the activated carbon, and restore its adsorption performance to a near-initial state, thus fully preparing it for subsequent adsorption operations.

[0040] S60, the mass concentration of H2S in the purified blast furnace gas output by the adsorption tower 10 in the adsorption state is greater than or equal to 10 mg / Nm 3 After that, the adsorption tower 10 which is in the adsorption state at this time is switched to the regeneration state, and at the same time, the adsorption tower 10 which is in the regeneration state at this time is switched to the adsorption state; Among them, the mass concentration of H2S in the purified blast furnace gas output by the adsorption tower 10 in the adsorption state is greater than or equal to 10mg / Nm³, which is used as a trigger condition. The adsorption tower 10 in the adsorption state at this time is switched to the regeneration state, and the adsorption tower 10 in the regeneration state is switched to the adsorption state at the same time, realizing the cyclic switching of the adsorption and regeneration states between the adsorption towers 10, ensuring the continuous and efficient operation of the entire system and continuously performing desulfurization and purification treatment on the blast furnace gas.

[0041] S70, repeating steps S40 to S60 multiple times until the breakthrough sulfur capacity of the activated carbon in the adsorption tower 10 is less than 5%.

[0042] Among them, steps S40 to S60 are repeated many times to continuously optimize the regeneration effect of the activated carbon, so that it can maintain good adsorption performance for a long time, achieve the ultimate goal of efficient desulfurization, ensure that the entire fine desulfurization device 100 operates stably and reliably for a long time, and meet the quality requirements of the purified blast furnace gas in the production process.

[0043] Preferably, in step S20: the volume space velocity of the adsorption treatment is 500 to 1000 h -1 , the temperature is 40~80℃.

[0044] Preferably, in step S40: the volume space velocity of the in-situ thermal reduction regeneration treatment is 20 to 50 h -1 , the regeneration temperature is 280~320℃.

[0045] Preferably, in step S50, the volume space velocity of deep thermal reduction regeneration treatment is 20 to 50 h -1 , the regeneration temperature is 280~320℃.

[0046] Preferably, before performing step S60, the process further includes: maintaining the air velocity of the adsorption tower 10 in the regeneration state unchanged, returning the purified blast furnace gas to the adsorption tower 10 in the regeneration state for cooling treatment, and cooling the temperature in the adsorption tower 10 in the regeneration state to 40-120°C.

[0047] The technical solution of the present invention will now be further described with reference to specific embodiments.

[0048] Example 1 (two adsorption towers 10, one for adsorption and one for regeneration): See also Figure 3 , Figure 3 This is a schematic diagram of the overall structure of the fine desulfurization device for achieving activated carbon regeneration provided in Example 1 of the present application; Figure 3 It can be seen that Example 1 of the present invention provides a fine desulfurization device 100 for realizing activated carbon regeneration, comprising a first adsorption tower 11, a second adsorption tower 12, a fan 40, a heat exchanger 20 and a heater 30. The first adsorption tower 11 and the second adsorption tower 12 are connected in parallel and are both loaded with activated carbon. The heat exchanger 20, the heater 30 and the first adsorption tower 11 are sequentially connected by pipes to form a first closed loop. The heat exchanger 20, the heater 30 and the second adsorption tower 12 are sequentially connected by pipes to form a second closed loop. Among them, the cold fluid inlet of the heat exchanger 20 is used to alternately input purified blast furnace gas and converter gas, and the cold fluid outlet of the heat exchanger 20 is connected to the inlet of the heater 30; the hot fluid inlet of the heat exchanger 20 is connected to multiple adsorption towers 10, and the hot fluid outlet of the heat exchanger 20 is used to output the analysis gas.

[0049] Specifically, the first adsorption tower 11 and the second adsorption tower 12 are both connected to a first air inlet pipe, a second air inlet pipe, a first air outlet pipe and a second air outlet pipe. The first air inlet pipe is connected to a first gas storage tank loaded with blast furnace gas to be purified, the second air inlet pipe is connected to the outlet of the heater 30, the first air outlet pipe is respectively connected to the second gas storage tank loaded with purified blast furnace gas and the cold fluid inlet of the heat exchanger 20, and the second air outlet pipe is connected to the hot fluid inlet of the heat exchanger 20.

[0050] Furthermore, a first adsorption inlet valve 511 is installed on the first air inlet pipe of the first adsorption tower 11, a first regeneration inlet valve 512 is installed on the second air inlet pipe, a first adsorption outlet valve 513 and a fourth valve 54 are installed on the first air outlet pipe, a first regeneration outlet valve 515 is installed on the second air outlet pipe, and the second air storage tank is located between the first adsorption outlet valve 513 and the fourth valve 54.

[0051] Furthermore, a second adsorption inlet valve 521 is installed on the first air inlet pipe of the second adsorption tower 12, a second regeneration inlet valve 522 is installed on the second air inlet pipe, a second adsorption outlet valve 523 and a fourth valve 54 are installed on the first air outlet pipe, a second regeneration outlet valve 525 is installed on the second air outlet pipe, and the second air storage tank is located between the second adsorption outlet valve 523 and the fourth valve 54.

[0052] Specifically, the fine desulfurization device 100 for realizing activated carbon regeneration also includes a fan 40 and a sixth valve 56. One end of the fan 40 is connected to the cold fluid inlet of the heat exchanger 20, and the other end of the fan 40 is respectively connected to the second ends of the fourth valve 54 and the sixth valve 56. The first end of the sixth valve 56 is connected to the third gas storage tank loaded with converter gas.

[0053] Furthermore, the specific steps of the fine desulfurization method for achieving activated carbon regeneration provided in Example 1 of the present invention are as follows: Step 1 (adsorption stage): The first adsorption tower 11 is put into operation, and the second adsorption tower 12 is kept in standby. Specifically, the first regeneration inlet valve 512, the second adsorption inlet valve 521, the second regeneration inlet valve 522, the first regeneration outlet valve 515, the second adsorption outlet valve 523, the second regeneration outlet valve 525, the fourth valve 54, and the sixth valve 56 are closed. The first adsorption inlet valve 511 and the first adsorption outlet valve 513 are opened, and the blast furnace gas to be purified containing H2S enters the first adsorption tower 11 through the first adsorption inlet valve 511 at a volume space velocity of 1000 h / min. -1 The adsorption temperature is 60°C, and the H2S is removed by activated carbon adsorption to obtain purified blast furnace gas, which flows out through the first adsorption outlet valve 513 (15).

[0054] After purification, H2S in blast furnace gas reaches the set value of 10mg / Nm 3After that, the second adsorption tower 12 is put into use and the first adsorption tower 11 is turned into the regeneration state. First, the second adsorption inlet valve 521 and the second adsorption outlet valve 523 are opened in sequence, and then the first adsorption inlet valve 511 and the first adsorption outlet valve 513 are closed in sequence.

[0055] Step 2 (heating process in the regeneration stage): open the first regeneration inlet valve 512, the first regeneration outlet valve 515 and the blast furnace gas valve in sequence, the blower 40 extracts the purified blast furnace gas, and preheats the purified blast furnace gas by using the waste heat of the analytical gas through the heat exchanger 20; then the purified blast furnace gas enters the heater 30, where it is heated to 300°C; then the purified blast furnace gas enters the first adsorption tower 11 to be regenerated through the first regeneration inlet valve 512, and the temperature in the first adsorption tower 11 is raised to the regeneration temperature of 300°C, and the volume space velocity is 50h -1 .

[0056] Step 3 (initial regeneration process in the regeneration stage): Maintain the space velocity and temperature during the heating process and continue regeneration for 24 hours.

[0057] Step 4 (deep regeneration process in the regeneration stage): The purified blast furnace gas is switched to converter gas through the combined action of the fourth valve 54 and the sixth valve 56, and the space velocity and temperature in the initial regeneration process of step 3 are maintained, and regeneration is continued for 48 hours.

[0058] Step 5 (cooling process during the regeneration stage): The converter gas is switched back to the purified blast furnace gas through the combined action of the fourth valve 54 and the sixth valve 56, and the heater 30 is turned off to maintain the original space velocity conditions, and the first adsorption tower 11 is cooled to 60°C, the temperature required for the adsorption process; the high-temperature desorption gas generated during the regeneration process flows out through the first regeneration outlet valve 515 and is preheated by the heat exchanger 20 to the regeneration carrier gas.

[0059] Step 6 (regeneration cycle stage): After purification, the H2S content in the blast furnace gas reaches the set value of 10mg / Nm 3 After that, the first adsorption tower 11 is put into use, and the second adsorption tower 12 is switched to the regeneration state, and the operation is the same as the above process, and the cycle is repeated.

[0060] See also Figure 4 , Figure 4 Schematic diagram of the breakthrough sulfur capacity test results of the activated carbon during multiple cycles of adsorption regeneration under two conditions: simulated converter gas (CO concentration 67%) and simulated blast furnace gas (CO concentration 25%); wherein, Figure 4It can be seen that the fine desulfurization device 100 for achieving activated carbon regeneration provided in Example 1 of the present application has a significantly improved penetration sulfur capacity of activated carbon in a simulated converter gas atmosphere compared to a simulated blast furnace gas atmosphere, reaching 23% to 55%. The above results can predict that when the fine desulfurization device 100 for achieving activated carbon regeneration adopts a step-by-step regeneration mode of first regenerating in a blast furnace gas atmosphere and then deep regenerating in a converter gas atmosphere, it can achieve better regeneration effect at the same regeneration temperature, effectively extend the service life of the activated carbon, and thus reduce material costs.

[0061] In addition, compared with the adsorption process, the regeneration process is carried out at a higher temperature, that is, at the beginning and end of regeneration, the adsorption tower 10 is in a heating state and a cooling state respectively, and the fine desulfurization device 100 expands and contracts with heat, and the risk of leakage caused by damage to the fine desulfurization device 100 is high. In the middle and late stages of regeneration, the temperature of the fine desulfurization device 100 has stabilized, and the risk of leakage is low. The fine desulfurization device 100 for realizing activated carbon regeneration provided in Example 1 of the present application uses blast furnace gas with a relatively low CO concentration (low toxicity) at the beginning and end of regeneration, and uses converter gas with a relatively high CO concentration (high toxicity) in the middle and late stages of regeneration, which minimizes the risk of poisoning.

[0062] To sum up, different from the prior art, the fine desulfurization device 100 and fine desulfurization method for realizing activated carbon regeneration provided by the present invention use blast furnace gas to perform in-situ thermal reduction regeneration on the adsorbed activated carbon, and then use another converter gas with a higher CO content (about 70%) and stronger reducing property in the steel plant to perform deep regeneration on the activated carbon after preliminary regeneration, thereby achieving better regeneration effect at the same regeneration temperature, effectively extending the service life of the activated carbon, and reducing material costs.

[0063] The above are only preferred specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or replacements that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A fine desulfurization device for realizing activated carbon regeneration, characterized in that: The invention comprises at least two adsorption towers, each loaded with activated carbon, a heat exchanger and a heater, wherein the heat exchanger, the heater and any one of the adsorption towers are sequentially connected through pipelines to form a closed loop, and the activated carbon in each of the adsorption towers is used to adsorb the blast furnace gas to be purified to obtain the purified blast furnace gas; Among them, the cold fluid inlet of the heat exchanger is used to alternately input the purified blast furnace gas and converter gas, and the cold fluid outlet of the heat exchanger is connected to the inlet of the heater; the hot fluid inlet of the heat exchanger is connected to multiple adsorption towers, and the hot fluid outlet of the heat exchanger is used to output the analysis gas.

2. The fine desulfurization device for realizing activated carbon regeneration according to claim 1 is characterized in that: Each of the adsorption towers is connected to a first air inlet pipe, a second air inlet pipe, a first air outlet pipe and a second air outlet pipe. The first air inlet pipe is connected to a first gas storage tank loaded with the blast furnace gas to be purified, the second air inlet pipe is connected to the outlet of the heater, the first air outlet pipe is respectively connected to a second gas storage tank loaded with the purified blast furnace gas and the cold fluid inlet of the heat exchanger, and the second air outlet pipe is connected to the hot fluid inlet of the heat exchanger.

3. The fine desulfurization device for realizing activated carbon regeneration according to claim 2 is characterized in that: A first valve is installed on the first air inlet pipe, a second valve is installed on the second air inlet pipe, a third valve and a fourth valve are installed on the first air outlet pipe, and a fifth valve is installed on the second air outlet pipe; Wherein, the second gas storage tank is located between the third valve and the fourth valve.

4. The fine desulfurization device for realizing activated carbon regeneration according to claim 3 is characterized in that: A plurality of the adsorption towers are connected in parallel.

5. The fine desulfurization device for realizing activated carbon regeneration according to claim 3 is characterized in that: The fine desulfurization device for realizing activated carbon regeneration also includes a fan and a sixth valve, one end of the fan is connected to the cold fluid inlet of the heat exchanger, the other end of the fan is respectively connected to the second ends of the fourth valve and the sixth valve, and the first end of the sixth valve is connected to the third gas storage tank loaded with the converter gas.

6. A fine desulfurization method for realizing activated carbon regeneration, applicable to the fine desulfurization device for realizing activated carbon regeneration as claimed in any one of claims 1 to 5, characterized in that: The method comprises: S10, providing the fine desulfurization device, wherein the fine desulfurization device comprises at least two adsorption towers; S20, inputting the blast furnace gas to be purified into part of the adsorption towers for adsorption treatment to obtain the purified blast furnace gas and the analytical gas; S30, wait until the mass concentration of H2S in the purified blast furnace gas output by the adsorption tower is greater than or equal to 10 mg / Nm 3 After that, the adsorption tower after the blast furnace gas to be purified is inputted is switched to a regeneration state, and the adsorption tower after the blast furnace gas to be purified is not inputted is switched to an adsorption state; S40, returning the purified blast furnace gas to the adsorption tower in the regeneration state for in-situ thermal reduction regeneration treatment, so that the activated carbon in the adsorption tower in the regeneration state is converted into preliminary regenerated activated carbon; S50, inputting the converter gas into the adsorption tower in a regenerated state to perform deep thermal reduction regeneration treatment, so that the preliminary regenerated activated carbon is converted into deep regenerated activated carbon; S60, the mass concentration of H2S in the purified blast furnace gas output by the adsorption tower in the adsorption state is greater than or equal to 10 mg / Nm 3 After that, the adsorption tower which is in the adsorption state at this time is transferred to the regeneration state, and at the same time, the adsorption tower which is in the regeneration state at this time is transferred to the adsorption state; S70, repeating the steps S40 to S60 multiple times until the breakthrough sulfur capacity of the activated carbon in the adsorption tower is less than 5%.

7. The fine desulfurization method for realizing activated carbon regeneration according to claim 6, characterized in that: In the step S20: the volume space velocity of the adsorption treatment is 30 to 3000 h -1 , the temperature is 40~120℃.

8. The fine desulfurization method for achieving activated carbon regeneration according to claim 6, characterized in that: In the step S40: the volume space velocity of the in-situ thermal reduction regeneration treatment is 5 to 100 h -1 , the regeneration temperature is 200~400℃, and the regeneration time is 24~48h.

9. The fine desulfurization method for realizing activated carbon regeneration according to claim 6, characterized in that: In the step S50: the volume space velocity of the deep thermal reduction regeneration treatment is 5 to 100 h -1 , the regeneration temperature is 200~400℃, and the regeneration time is 24~48h.

10. The fine desulfurization method for realizing activated carbon regeneration according to claim 6, characterized in that: Before performing the S60 step, the method further includes: maintaining the air velocity of the adsorption tower in the regeneration state unchanged, returning the purified blast furnace gas to the adsorption tower in the regeneration state for cooling treatment, and cooling the temperature in the adsorption tower in the regeneration state to 40-120°C.

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