阅读说明：本技术 一种高炉气净化处理的方法 (Method for purifying blast furnace gas ) 是由 朱慧 朱学田 李梦龙 黄显著 于 2019-09-29 设计创作，主要内容包括：本发明针对高炉气的回收利用提出一种调整其含有的CO-2和H-2S、COS等硫化物至所要求规格的方法。本发明根据高炉气的组成和工艺特性,在急冷过程中将COS水解变成CO-2和H-2S,脱除H-2S后使用醇胺吸收法调整高炉气中的CO-2从普通级别至体积分数低至0.001%的化工合成应用级别、总硫低于<10mg/Nm～3。采用本发明提出的工艺方法,可以使高炉气净化工艺流程简洁,提高对低前潜硫H-2S、COS处理的技术经济性,可根据需要控制CO-2的脱除程度。(The invention provides a method for adjusting CO contained in blast furnace gas aiming at recycling of the blast furnace gas 2 And H 2 S, COS to required specification. According to the composition and technological characteristics of blast furnace gas, COS is hydrolyzed into CO in the quenching process 2 And H 2 S, removal of H 2 Adjusting CO in blast furnace gas by using alcohol amine absorption method after S 2 From the common grade to the chemical synthesis application grade with the volume fraction as low as 0.001 percent and the total sulfur of the sulfur is lower than<10mg/Nm 3 . The process method provided by the invention can simplify the purification process flow of the blast furnace gas and improve the purification effect on low-front latent sulfur H 2 S, COS process economics, CO control as required 2 The degree of removal of (a).)

1. A method for purifying blast furnace gas is characterized by comprising the following steps: (1) hydrolyzing COS contained in the initial blast furnace gas into CO by quenching₂And H₂S; (2) removal of H₂S, carrying out vulcanization treatment; (3) adjusting CO₂And (4) content value.

2. The method as claimed in claim 1, wherein the initial blast furnace gas at 80-200 ℃ is quenched to hydrolyze COS to CO₂And H₂S, residual COS is less than 5mg/Nm³(ii) a Removal of H by highly selective non-regenerable desulfurization solvents₂S, or selective removal of H₂S and H₂S is converted into elemental sulfur, so that the total sulfur in the discharged waste gas is less than 10mg/Nm³(ii) a CO adjustment in blast furnace gas using alcohol amine absorption process₂Volume fraction.

3. The method as claimed in claim 2, wherein a catalyst region with a built-in COS hydrolysis catalyst is arranged at the position 600-1000 mm higher than the top of the gas inlet of the quenching apparatus, and gas can only pass through the catalyst region; the filling height of the COS hydrolysis catalyst is 200-600 mm, and the hydrolysis rate of the COS hydrolysis catalyst is more than 95%.

4. The method according to claim 2, characterized in that in the desulfurization section, when the content of elemental sulfur in the feed gas is less than 2t/d, a nonrenewable liquid desulfurizing agent is used for desulfurization; when the content of the element sulfur in the feed gas is more than or equal to 2t/d, reproducible desulfurization is adopted for desulfurization and sulfur recovery is carried out.

5. The process according to claim 4, characterized in that the nonrenewable liquid desulfurizing agent is a liquid containing sodium hydroxide or sodium carbonate as basic substance, or a triazine-based desulfurizing agent, preferably a triazine-based desulfurizing agent.

6. The method of claim 4, wherein the regenerable desulfurization is an absorption process comprising an alcohol amine solvent and a super-gravity rotating bed or a micro-cyclone absorber or a dynamic wave scrubber, and the regenerated H-rich₂S gas enters a sulfur recovery reaction system, and H in waste gas after sulfur recovery₂S content less than 10mg/Nm³。

7. The process of claim 6, wherein the small sulfur recovery reactor comprises a fixed bed process for direct separation of H₂S is catalytically converted into elemental sulfur and wet oxidation methods such as an iron complexing method, a sulfonated cobalt phthalocyanine method, a tannin extract method and the like.

8. The method of claim 6, wherein the alcohol amine solvent selectively absorbs H₂The alcohol amine of S is a solvent consisting of one or more of N-methyldiethanolamine, 2-amino-2-methyl-1-propanol and tert-butyl diglycolamine; the temperature of the lean amine liquid entering the absorber is 20-35 ℃, and preferably 25-30 ℃; the gas-liquid ratio is 500-5000, preferably 800-4000; h in lean amine solution₂The S content is less than 1.0g/L, preferably less than 0.5 g/L.

9. The method of claim 1, wherein the decarbonization of the alcohol amine is performed by two-stage absorption and two-stage regeneration using a semi-lean solution as an absorbent.

10. The method according to claim 9, wherein the alcohol amine solvent is an MDEA formula type activated decarburization solvent, the process parameters are that the lean solution is 40-65 ℃, the semi-lean solution is 50-75 ℃, the regeneration tower top pressure is 25-100 kPa, and the lean solution flow rate is as follows: and the flow rate of the semi-lean solution is =1: 2.5-5.

Technical Field

The invention aims at the recycling of blast furnace gasBy providing a means for regulating the CO content thereof₂And H₂S, COS, belonging to the technical field of metallurgy.

Background

Blast furnace gas is a byproduct generated at the furnace top in the metallurgical iron-making process, and the components and the heat value of the blast furnace gas are related to the fuel used by the blast furnace, the variety of the pig iron and the smelting process. Generally, the main components of blast furnace gas are CO and CO₂、N₂、H₂、CH₄Etc., in which the combustible components are mainly CO, H₂、CH₄The content of (A) is very small, the content of CO is about 25-50%, and the rest components are mainly CO₂、N₂And occupies CO₂About 15% to 35% of the total gas fraction. Besides, it also contains trace H₂S, COS, etc., and the content thereof is usually several tens to several hundreds mg/Nm³. As the calorific value of the blast furnace gas is not high, the blast furnace gas is basically used as self-use fuel gas in the past. Modern iron-making production generally adopts production processes with large volume, high air temperature, high smelting intensity and high coal powder injection amount, and the advanced production processes improve labor productivity and reduce energy consumption, but the heat value of the produced blast furnace gas is lower, and the utilization difficulty is increased. With the increasing strictness of the environmental protection policy and the support of the country on energy conservation and environmental protection, the heat value in the blast furnace gas is currently recovered and even becomes a profit growth point for metallurgical iron making, and the development of the energy-saving metallurgical iron making industry can be promoted.

In order to improve the availability and the calorific value of the recovered blast furnace gas, the CO which can not provide the reduction effect and the calorific value in the blast furnace gas needs to be reduced₂And corrosive H₂S, COS, otherwise, the recovered blast furnace gas product is not qualified whether as high-heat value fuel, as reducing gas for iron making or as raw material of downstream chemical industry. Meanwhile, the metallurgy-based iron and steel industry of China and CO in the production process₂Emission of CO in the world₂5 to 6 percent of total emission, blast furnace ironmaking CO₂The emission amount of CO accounts for the whole steel production₂70% of the emission, thereby reducing CO in the ironmaking process₂The emission is a key way for realizing the coal reduction in the steel industry.

Industrial adjustment of CO in gas₂、H₂S, COS, there are many technical methods, and for the working condition of large gas handling capacity, there are physical absorption method, chemical absorption method, adsorption method, etc. commonly used. The physical absorption method and the adsorption method are very beneficial when being carried out under high pressure and low temperature, the blast furnace gas has large quantity and low pressure, if the physical absorption is used, the gas needs to be compressed to more than 2.0MPa, even if the physical absorption is used, the gas needs to be compressed to more than 0.5MPa, otherwise, the physical absorption method can not be used, and the adsorption under the lower pressure not only leads to a plurality of adsorption beds, large occupied area and low purification efficiency, but also leads to quite high one-time investment and operation cost. Chemical absorption can deal with absorption of gases at low pressure, e.g. absorption of CO from flue gases by amine method of MEA₂CO in natural gas₂And H₂And S. For blast furnace gas, the treatment capacity is large, and CO in the gas₂And H₂S, COS, the content difference is large, and in the face of severe environmental regulations, if the process configuration of the chemical absorption method is improper, the process is long, the consumption is large, and the technical and economic level is not high. For H industrially₂S, COS, it is important to arrange for reasonable removal of the removed sulfides, which is a new problem. However, the sulfur content in the blast furnace gas is low, which is not enough to use the Claus sulfur recovery process commonly used in industry, otherwise the investment is large and the operation stability is difficult to ensure. Also, for wet oxidation, high concentrations of CO in blast furnace gas are preferred, although better economics are achieved for low latent sulfur conditions₂It is also a significant challenge, together with the organic sulfur COS. Thus, existing gases are deprived of CO₂、H₂S, COS, the process method can not be simply combined and is suitable for the purification treatment of blast furnace gas to adjust the CO in the composition₂And H₂S, COS to the specified requirements.

Disclosure of Invention

The invention aims to simplify the process flow of blast furnace gas purification and improve the purification effect on low-front latent sulfur H₂S, COS technical economy of processing. The invention provides a method for removing CO from blast furnace gas according to the composition and process characteristics of the blast furnace gas₂、H₂S, COS Process for hydrolyzing COS to CO in quenching process₂And H₂S, followed by the desulfurization of H with a highly selective desulfurization solvent₂S removal, and finally, adjusting CO in the blast furnace gas by using an absorption method₂From the general level to the chemical synthesis application level.

The main technical scheme of the invention comprises the following steps: (1) hydrolyzing COS contained in the initial blast furnace gas into CO in a quenching device₂And H₂S; (2) removing H from blast furnace gas₂S, carrying out vulcanization treatment; (3) adjusting CO in blast furnace gas₂Content value product specification.

Further, the technical scheme of the invention is explained.

The invention hydrolyzes the trace COS contained in the blast furnace gas into CO in the quenching process₂And H₂S: after the blast furnace gas leaves the blast furnace, the temperature is generally maintained at 80-200 ℃, preferably 150-200 ℃ after heat recovery and dust removal, a COS catalytic hydrolysis area is arranged above a gas inlet of a quenching device at a certain distance, the temperature of the blast furnace gas is fully utilized to promote hydrolysis, and the COS is reduced to 5mg/Nm by a hydrolysis catalyst³The following.

The area for catalytic conversion of COS is determined according to the structural form of the quenching tower. If the quenching tower adopts a plate tower, a second tower plate of the quenching tower counted from bottom to top is changed into a catalyst area capable of filling a height of 600 mm; if the tower is a packed tower, the packing 600-1000 mm away from the uppermost end of the inlet pipeline opening at the bottom of the tower is changed into a catalyst area capable of being filled with the catalyst with the height of 600 mm; if the quench tower uses a tower with a built-in venturi jet for cooling, a catalytic hydrolysis area with the height of 600mm is independently arranged at the position 600-1000 mm away from the uppermost end of the air pipe opening, and the blast furnace gas can only flow through the catalytic hydrolysis area.

The hydrolysis catalyst zone is filled with a common or low-temperature type COS hydrolysis catalyst, the hydrolysis rate of which is required to be not less than 95%, and the low-temperature type COS hydrolysis catalyst is preferred. H generated by hydrolyzing trace COS in blast furnace gas₂S and original H in blast furnace gas₂And S enters a subsequent desulfurization working section together.

The desulfurization section of the invention: due to H contained in the blast furnace gas₂S, COS is trace, and has low content of COS after hydrolysis, and overall H although blast furnace gas flow is large₂The S amount is small, and a desulfurization scheme is further optimized in a desulfurization link according to the specific low potential sulfur amount.

When the amount of the latent sulfur is less than 2t/d, a non-renewable selective liquid absorbent is selected to absorb only H₂S, preferably a triazine liquid desulfurizing agent; when the potential sulfur content is higher than 2t/d, a renewable absorption process consisting of an alcohol amine solvent and a super-gravity rotating bed or a micro-cyclone absorber or a dynamic wave scrubber is firstly used for strengthening H from two aspects of dynamics and mass transfer equipment₂Selective absorption of S followed by regeneration rich in H₂S gas enters a sulfur recovery reactor, and H is directly recovered by a fixed bed method₂S is catalytically converted into elemental sulfur and wet oxidation methods such as an iron complexing method, a sulfonated cobalt phthalocyanine method, a tannin extract method and the like.

For the sulfur recovery reactor, the design time is to discharge H in the waste gas₂S content less than 10mg/Nm³The waste gas is not required to be provided with a torch for combustion, and the waste gas is directly discharged into the atmosphere at a high point.

For selective dehydrogenation of H₂The alcohol amine solvent of S is selected so as to selectively absorb H₂The desulfurizing agent for S may be any solvent, preferably N-methyldiethanolamine, 2-amino-2-methyl-1-propanol, t-butyldiglycolamine, or a combination of the above-mentioned preferred solvents. In addition, the main absorption process parameters are characterized in that the temperature of the absorption liquid entering the absorber is 20-35 ℃, and preferably 25-30 ℃; the gas-liquid ratio is 500-5000, preferably 800-4000; h in lean amine solution₂The S content is less than 1.0g/L, preferably less than 0.5 g/L.

The decarburization process of the invention comprises the following steps: and selecting reasonable compression pressure according to downstream requirements and the blast furnace gas quantity, and controlling the pressure to be 0.6-4.0 MPa. The specific configuration of the decarburization process can be a one-stage absorption one-stage regeneration process configuration, or a two-stage absorption two-stage regeneration process, preferably a two-stage absorption two-stage regeneration process.

CO in the decarbonized blast furnace gas₂Can be as low as 0.001 percent according to the requirement, and can also be adjusted to a value specified by a user. The decarbonizing solvent is preferably MDEA formulaThe main process parameters of the decarbonization solvent are that the lean solution is 40-65 ℃, the pressure at the top of the regeneration tower is 25-100 kPaG, and if the two-stage absorption and two-stage regeneration process is adopted, the flow rate of the half lean solution is 50-75 ℃: and the flow rate of the semi-lean solution is =1: 2.5-5.

After the blast furnace gas is treated by the technical scheme provided by the invention, the total sulfur of sulfides in the blast furnace gas product can be lower than 10mg/Nm³Even below 1mg/Nm³And CO₂The content is adjusted in a wide range, and the volume fraction can reach 0.001 percent at the lowest.

Meanwhile, the invention consumes less non-renewable liquid desulfurizer; when using a regenerable desulfurization agent, the desulfurization equipment is simple and compact, and the resulting rich H is obtained due to selective desulfurization₂The S acid gas amount is less, and the sulfur recovery device is also miniaturized; after the two previous treatment steps, the decarbonization process gas is basically free of sulfide, so that regenerated CO₂The gas is also substantially free of sulfides.

The invention provides a method for removing CO in blast furnace gas according to the composition and the upstream and downstream process characteristics of the blast furnace gas₂、H₂S, COS the method makes full use of the characteristics of the blast furnace gas, and can flexibly adjust and purify CO in the blast furnace gas tail gas according to the subsequent use of the blast furnace gas₂Content of (b), arranging H reasonably₂S, COS sulfide treatment process, providing process technology economy.

Therefore, the technical scheme of the invention can economically and environmentally realize the component CO of the blast furnace gas₂And H₂S, COS.

Drawings

FIG. 1 is a schematic process flow diagram of a process according to an embodiment of the invention.

FIG. 1 is a diagram illustrating the embodiment of the present invention for adjusting CO in blast furnace gas₂、H₂S, COS content to product specification. The flexible process can be reasonably designed on the basis of basic process according to actual needs.

In the figure: 01-recovering heat and dedusting blast furnace gas, quenching and hydrolyzing COS in 02-blast furnace gas, desulfurizing 03-blast furnace gas, decarbonizing 04-blast furnace gas, sending 05-blast furnace gas to subsequent process, and removing H in 06-nonrenewable method₂S, 07-renewable alopecia H₂And S and sulfur recovery.

Detailed Description

The present invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.

The typical blast furnace gas purification treatment process method of the embodiment of the invention is shown in the attached figure 1, but the technical scheme of the invention is not limited to the process method shown in the attached figure 1 in practical use.

Referring to the attached figure 1, high-temperature blast furnace gas from a blast furnace enters a quenching and COS hydrolysis working section (2) after heat recovery and dust removal (1). At the position (2), the catalyst is used for catalyzing and hydrolyzing COS into CO by utilizing the high-saturation steam atmosphere with high residual heat and sharp cooling of blast furnace gas₂、H₂S, residual COS of blast furnace gas is less than 5mg/Nm³. And (3) the blast furnace gas from the step (2) enters a desulfurization section (3), and the non-renewable type desulfurization (6) or the renewable type desulfurization and sulfur recovery (7) is selected for desulfurization according to the actual treatment capacity of the blast furnace gas and the originally-contained COS and H2S. And (3) the desulfurized blast furnace gas enters a blast furnace gas decarburization working section (4), an industrial common chemical absorption decarburization process can be applied to the decarburization working section (4), and finally the blast furnace gas leaves the system and enters a subsequent working procedure (5).

Example 1

The quenching packed tower is filled with COS low-temperature hydrolysis catalyst with the height of 250 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 180 ℃, wherein COS is 50mg/Nm calculated by sulfur³，H₂S 100mg/Nm³. In the desulfurization section, 40-80% of triazine liquid desulfurizing agent is used as absorption liquid to remove H₂S, compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas<1mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001% -5% (volume fraction) according to the requirement, every 10⁴Nm³The consumption of the non-renewable triazine liquid desulfurizer of the blast furnace gas is less than 5L.

Example 2

Quench packed tower packingCOS low-temperature hydrolysis catalyst with the height of 400 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 200 ℃, wherein COS is 100mg/Nm calculated by sulfur³，H₂S 200mg/Nm³. In the desulfurization section, 40-80% of triazine liquid desulfurizing agent is used as absorption liquid to remove H₂S, compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas<2mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001% -5% (volume fraction) according to the requirement, every 10⁴Nm³The consumption of the non-renewable triazine liquid desulfurizer of the blast furnace gas is lower than 8L.

Example 3

The quenching packed tower is filled with COS low-temperature hydrolysis catalyst with the height of 600 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 200 ℃, wherein COS is 100mg/Nm calculated by sulfur³，H₂S 500mg/Nm³. In the desulfurization section, 40-80% of triazine liquid desulfurizing agent is used as absorption liquid to remove H₂S, compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas<2mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001% -5% (volume fraction) according to the requirement, every 10⁴Nm³The consumption of the non-renewable triazine liquid desulfurizer of the blast furnace gas is lower than 20L.

Example 4

The quenching packed tower is filled with COS low-temperature hydrolysis catalyst with the height of 250 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 200 ℃, wherein COS accounts for 50mg/Nm in terms of sulfur³，H₂S 2000mg/Nm³. The desulfurization section removes H by absorption equipment consisting of selective desulfurization alcohol amine and a super-gravity selective bed₂S, absorbs H₂And (4) after S is regenerated, the regenerated S enters a complex iron desulphurization device to recover elemental sulfur, and then the waste gas is discharged in a high-point emptying manner. The temperature of the lean amine liquid entering the super-gravity rotating bed is 25 ℃, the gas-liquid ratio is 800, and H in the lean amine liquid₂The S content was 0.35 g/L.And (4) compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas<2mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001 percent and 5 percent (volume fraction) according to the requirement, and the total sulfur in the waste gas is discharged at a high point<10 mg/Nm³。

Example 5

The quenching packed tower is filled with COS low-temperature hydrolysis catalyst with the height of 500 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 200 ℃, wherein COS is 100mg/Nm calculated by sulfur³，H₂S 3000mg/Nm³. The desulfurization section removes H by absorption equipment consisting of selective desulfurization alcohol amine and a super-gravity selective bed₂S, absorbs H₂And (4) after S is regenerated, the regenerated S enters a complex iron desulphurization device to recover elemental sulfur, and then the waste gas is discharged in a high-point emptying manner. The temperature of the lean amine liquid entering the super-gravity rotating bed is 25 ℃, the gas-liquid ratio is 800, and H in the lean amine liquid₂The S content was 0.35 g/L. And (4) compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas<2mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001 percent and 5 percent (volume fraction) according to the requirement, and the total sulfur in the waste gas is discharged at a high point<10 mg/Nm³。

Example 6

The quenching packed tower is filled with COS low-temperature hydrolysis catalyst with the height of 600 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 200 ℃, wherein COS is 200mg/Nm calculated by sulfur³，H₂S 3000mg/Nm³. The desulfurization section removes H by absorption equipment consisting of selective desulfurization alcohol amine and a super-gravity selective bed₂S, absorbs H₂And (4) after S is regenerated, the regenerated S enters a complex iron desulphurization device to recover elemental sulfur, and then the waste gas is discharged in a high-point emptying manner. The temperature of the lean amine liquid entering the super-gravity rotating bed is 25 ℃, the gas-liquid ratio is 800, and H in the lean amine liquid₂The S content was 0.35 g/L. And (4) compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After the processes of quenching and desulfurization treatment are carried out,COS in blast furnace gas<5mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001 percent and 5 percent (volume fraction) according to the requirement, and the total sulfur in the waste gas is discharged at a high point<10 mg/Nm³。

Example 7

The quenching packed tower is filled with COS low-temperature hydrolysis catalyst with the height of 600 mm. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 200 ℃, wherein COS is 200mg/Nm calculated by sulfur³，H₂S 3000mg/Nm³. The desulfurization section removes H by absorption equipment consisting of selective desulfurization alcohol amine and a super-gravity selective bed₂S, absorbs H₂And after S is regenerated, the regenerated S enters a cobalt phthalocyanine desulfurization device to recover elemental sulfur, then the waste gas is discharged in a high-point emptying manner, and the cobalt phthalocyanine content in the sulfur recovery device is 40 ppm. The temperature of the lean amine liquid entering the super-gravity rotating bed is 25 ℃, the gas-liquid ratio is 800, and H in the lean amine liquid₂The S content was 0.35 g/L. And (4) compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas<5mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, CO in blast furnace gas₂The content can be adjusted between 0.001 percent and 5 percent (volume fraction) according to the requirement, and the total sulfur in the waste gas is discharged at a high point<10 mg/Nm³。

Comparative example 1

The quenching packed tower is not filled with COS low-temperature hydrolysis catalyst. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 180 ℃, wherein COS is 50mg/Nm calculated by sulfur³，H₂S 100mg/Nm³. In the desulfurization section, 40-80% of triazine liquid desulfurizing agent is used as absorption liquid to remove H₂S, compressing the desulfurized gas to 0.8MPa, and entering a two-stage absorption and two-stage regeneration amine decarburization process. After quenching and desulfurization treatment, COS in the blast furnace gas is 30-40 mg/Nm³、H₂S<1mg/Nm³(ii) a After decarburization treatment, COS is 25-30mg/Nm in blast furnace gas³、CO₂The content can be adjusted between 0.001% -5% (volume fraction) according to the requirement, every 10⁴Nm³The consumption of the non-renewable triazine liquid desulfurizer of the blast furnace gas is less than 5L.

Comparative example 2

The quenching packed tower is not filled with COS low-temperature hydrolysis catalyst and is not desulfurized. The pressure of blast furnace gas used in the test is 25kPa, the blast furnace gas enters a quenching tower at 180 ℃, wherein COS is 50mg/Nm calculated by sulfur³，H₂S 100mg/Nm³. After quenching and decarburization treatment, COS is 30-40 mg/Nm in the blast furnace gas³、H₂S<1mg/Nm³、CO₂The content can be adjusted between 0.001 percent and 5 percent (volume fraction) according to the requirement; in the initial blast furnace gas CO₂When the volume fraction content is 25 percent, decarbonizing and regenerating CO₂Total sulfur content in gas>420mg/Nm³And H₂S content far greater than 10mg/Nm³At this time, CO₂Cannot be directly utilized or vented to the atmosphere.