阅读说明：本技术 一种高炉煤气精脱硫工艺 (Blast furnace gas fine desulfurization process ) 是由 赵荣志 冷廷双 李璟 丁林 张秋林 于 2019-10-15 设计创作，主要内容包括：本发明提供一种高炉煤气精脱硫工艺,属于煤气脱硫技术领域。该工艺具体为：高炉煤气经过布袋除尘后进入有机硫水解系统,水解后的煤气进入余压透平发电装置后,再进入湿法碱洗脱硫系统。其中,有机硫水解系统包括水解反应器和声波吹灰系统,湿法碱洗脱硫系统包括吸收塔、循环水槽、循环水泵、碱液储罐、碱液泵、工艺水箱和工艺水泵。该工艺可以有效地降低水解系统造成的阻力损失,为企业节约较大的运行成本。(The invention provides a blast furnace gas fine desulfurization process, belonging to the technical field of gas desulfurization. The process specifically comprises the following steps: the blast furnace gas enters an organic sulfur hydrolysis system after being subjected to bag dust removal, and enters a wet alkali washing desulfurization system after entering a residual pressure turbine power generation device. Wherein, the organic sulfur hydrolysis system comprises a hydrolysis reactor and a sound wave soot blowing system, and the wet alkali washing desulfurization system comprises an absorption tower, a circulating water tank, a circulating water pump, an alkali liquor storage tank, an alkali liquor pump, a process water tank and a process water pump. The process can effectively reduce the resistance loss caused by a hydrolysis system and save greater operation cost for enterprises.)

1. A blast furnace gas fine desulfurization process is characterized in that: the process comprises the following steps: the blast furnace gas enters an organic sulfur hydrolysis system after being subjected to bag dust removal, and the hydrolyzed gas enters a residual pressure turbine power generation device and then enters a wet alkali washing desulfurization system to finish the fine desulfurization of the blast furnace gas.

2. The blast furnace gas fine desulfurization process according to claim 1, characterized in that: the organic sulfur hydrolysis system comprises a hydrolysis reactor and a sound wave soot blowing system, wherein the sound wave soot blowing system is arranged at the upper part of the hydrolysis reactor.

3. The blast furnace gas fine desulfurization process according to claim 1, characterized in that: the wet alkali washing desulfurization system comprises an absorption tower, a circulating water tank, a circulating water pump, an alkali liquor storage tank, an alkali liquor pump, a process water tank and a process water pump, wherein the absorption tower is connected with a residual pressure turbine power generation device, a sprayer in the absorption tower is connected with the process water tank, a spraying layer in the absorption tower is connected with the circulating water tank through the circulating water pump, the circulating water tank and the process water tank are simultaneously connected with the alkali liquor storage tank, the alkali liquor pump is arranged between the alkali liquor storage tank and the circulating water tank, and the water outlet of the process water tank is connected.

4. The blast furnace gas fine desulfurization process according to claim 2, characterized in that: the temperature in the hydrolysis reactor is 80-200 ℃, and the pressure is 50-300 kPa.

5. The blast furnace gas fine desulfurization process according to claim 2, characterized in that: the organic sulfur in the blast furnace gas is converted into hydrogen sulfide by a hydrolytic agent in the hydrolytic reactor, wherein the hydrolytic agent is honeycomb-shaped, the height of a hydrolytic agent unit module is less than 1.3m, the section size is 150mm multiplied by 150mm, and the number of section holes is 40 multiplied by 40.

6. The blast furnace gas fine desulfurization process according to claim 2, characterized in that: the sound wave soot blowing system comprises sound wave soot blowers, the upper part of each layer of hydrolysis reactor is provided with the sound wave soot blowers, and the blowing time of the sound wave soot blowers is 10s and the interval is 50 s.

7. The blast furnace gas fine desulfurization process according to claim 1, characterized in that: and the blast furnace gas after passing through the residual pressure turbine power generation device enters from the bottom of an absorption tower of the wet desulphurization system.

Technical Field

The invention relates to the technical field of gas desulfurization, in particular to a blast furnace gas fine desulfurization process.

Background

At present, blast furnace gas dust removal adopts an all-dry method, and is influenced by properties of blast furnace burden, sinter and the like. The blast furnace gas after the residual pressure power generation has a great amount of acidic condensed water separated out along with the reduction of temperature and pressure, which is easy to accelerate the corrosion of the subsequent process pipeline and cause the shutdown and maintenance of users due to the gas leakage. Meanwhile, by analyzing the sulfide components of the blast furnace gas, the total sulfur content in the blast furnace gas is generally 60-100mg/Nm3, wherein organic sulfur accounts for 3/4, and inorganic sulfur accounts for 1/4.

Because the carbonyl sulfide in the blast furnace gas is known later, the components, the content, the harm and the removal technology of the carbonyl sulfide have not been paid attention. At present, no technology and corresponding process equipment suitable for removing carbonyl sulfide in blast furnace gas in the steel industry exist in China. Under the circumstances, it is necessary to research the reaction characteristics of carbonyl sulfide and further develop a technology and a process equipment capable of effectively removing carbonyl sulfide in blast furnace gas of iron and steel enterprises, and the achievement is to further reduce SO₂The discharge provides effective technical support and has important practical significance.

As in the Chinese patent: CN109609202A, "a method for desulfurizing and purifying blast furnace gas", describes a method of using the temperature and pressure of blast furnace gas to perform organic sulfur conversion, hydrolyze carbonyl sulfide into hydrogen sulfide, and then remove sulfide in blast furnace gas. However, the pressure loss caused by the method is large, the TRT can reduce a large amount of generated energy every year, and no successful case exists at present.

Therefore, aiming at the current situation, the invention develops a novel process which can reduce the pressure drop and the TRT/BPRT power generation loss while converting carbonyl sulfide into hydrogen sulfide.

Disclosure of Invention

The invention aims to provide a blast furnace gas fine desulfurization process.

The process specifically comprises the following steps: the blast furnace gas enters an organic sulfur hydrolysis system after being subjected to bag dust removal, and the hydrolyzed gas enters a residual pressure turbine power generation device and then enters a wet alkali washing desulfurization system to finish the fine desulfurization of the blast furnace gas.

The organic sulfur hydrolysis system comprises a hydrolysis reactor and a sound wave soot blowing system, wherein the sound wave soot blowing system is arranged at the upper part of the hydrolysis reactor.

The wet alkali washing desulfurization system comprises an absorption tower, a circulating water tank, a circulating water pump, an alkali liquor storage tank, an alkali liquor pump, a process water tank and a process water pump, wherein the absorption tower is connected with a residual pressure turbine power generation device, a sprayer in the absorption tower is connected with the process water tank, a spraying layer in the absorption tower is connected with the circulating water tank through the circulating water pump, the circulating water tank and the process water tank are simultaneously connected with the alkali liquor storage tank, the alkali liquor pump is arranged between the alkali liquor storage tank and the circulating water tank, and the process water pump is connected at the water.

The temperature in the hydrolysis reactor is 80-200 ℃, and the pressure is 50-300 kPa.

The organic sulfur in the blast furnace gas is converted into hydrogen sulfide by a hydrolytic agent in the hydrolytic reactor, wherein the hydrolytic agent is honeycomb-shaped, the height of a hydrolytic agent unit module is less than 1.3m, the section size is 150mm multiplied by 150mm, and the number of section holes is 40 multiplied by 40.

The sound wave soot blowing system comprises sound wave soot blowers, the upper parts of all the hydrolysis reactors are provided with different numbers of sound wave soot blowers according to the requirements, the blowing time of the sound wave soot blowers is 10s, and the interval is 50 s.

The blast furnace gas after passing through the residual pressure turbine power generation device enters from the bottom of an absorption tower of the wet desulphurization system.

The technical scheme of the invention has the following beneficial effects:

in the scheme, the resistance loss caused by the hydrolysis system can be effectively reduced, and the large operation cost is saved for enterprises.

Drawings

FIG. 1 is a schematic view of the fine desulfurization process of blast furnace gas.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

The invention provides a blast furnace gas fine desulfurization process, as shown in figure 1, in the process, the blast furnace gas enters an organic sulfur hydrolysis system after being subjected to bag dust removal, and the hydrolyzed gas enters a residual pressure turbine power generation device and then enters a wet alkali washing desulfurization system to finish the blast furnace gas fine desulfurization.

The organic sulfur hydrolysis system comprises a hydrolysis reactor and a sound wave soot blowing system, wherein the sound wave soot blowing system is arranged at the upper part of the hydrolysis reactor.

The wet alkali washing desulfurization system comprises an absorption tower, a circulating water tank, a circulating water pump, an alkali liquor storage tank, an alkali liquor pump, a process water tank and a process water pump, wherein the absorption tower is connected with a residual pressure turbine power generation device, a sprayer in the absorption tower is connected with the process water tank, a spraying layer in the absorption tower is connected with the circulating water tank through the circulating water pump, the circulating water tank and the process water tank are simultaneously connected with the alkali liquor storage tank, the alkali liquor pump is arranged between the alkali liquor storage tank and the circulating water tank, and the process water pump is connected at the water.

The temperature in the hydrolysis reactor is 80-200 ℃, and the pressure is 50-300 kPa.

The process is designed aiming at the current situation that no successful case falls to the ground at present in organic sulfur desulfurization treatment at the front end of blast furnace gas. In the solutions provided by some enterprises at present, the carbonyl sulfide hydrolysis process involved causes large pressure loss, so that the annual running cost is increased, and the iron and steel enterprises are difficult to accept. The invention combines the existing working condition of blast furnace gas, adopts the self-developed carbonyl sulfide hydrolysis catalyst, and reduces the pressure loss of the hydrolysis section to the acceptable range of enterprises while achieving the removal of organic sulfur by changing the form of the catalyst and the type of the hydrolysis reactor.

The invention develops a carbonyl sulfide hydrolysis process by combining the process flow of blast furnace gas in the steel industry at present, and solves the problem of difficult treatment of organic sulfur in the blast furnace gas at the source on the basis of not influencing TRT power generation. Meanwhile, a hydrogen sulfide removal system is additionally arranged after TRT power generation, so that the blast furnace gas of the iron and steel enterprise can be deeply purified before entering downstream users for use, the problem that the smoke emission of the downstream users of the blast furnace gas in the industry exceeds the standard is solved, the technology reaches the leading level of the industry, and the method has higher advantages compared with tail end treatment.

In the process, blast furnace gas subjected to cloth bag dust removal enters from the top of a hydrolysis tower and is contacted with a hydrolysis catalyst in the tower, and organic sulfur in the blast furnace gas is converted into hydrogen sulfide under the action of a self-developed hydrolysis agent (the temperature is 80-200 ℃, and the pressure is 50-300 kPa). Meanwhile, in order to prevent the catalyst of the hydrolysis system from being blocked, the blowing system is added with a sound wave blowing system to carry out purging periodically. The sound wave type soot blower has the advantages of short soot blowing time, high purging frequency, small relative consumption and short purging interval, compressed air only plays a role of diaphragm sound production, fly ash can float in flue gas, blockage is prevented, soot blowing dead angles do not exist, and the sound wave type soot blower has the advantages of small space requirement, convenience in maintenance, small catalyst abrasion and the like.

The blast furnace gas after power generation enters from the lower part of the absorption tower to be in countercurrent contact with alkali liquor in the absorption tower, sulfides in the gas phase are absorbed and removed by the liquid phase, the purified blast furnace gas is separated by a demister from the top of the absorption tower, the gas enters a gas pipe network, and the liquid returns to the bottom of the absorption tower and enters a circulating water tank; the circulating water is sent into the absorption tower again through the circulating water pump.

This will be described in connection with a specific dormitory building.

The blast furnace gas from the bag-type dust removal is contacted with a catalyst in a hydrolysis tower at the temperature of 80-200 ℃ and the pressure of 100-300 kPa, and organic sulfur is converted into hydrogen sulfide under the action of a hydrolyzing agent. The catalyst is in a honeycomb form, so that the resistance loss of the bed layer can be effectively reduced, and meanwhile, according to the pressure drop between catalyst bed layers, the sound wave soot blowing device is additionally arranged and is periodically started, so that the resistance loss is further reduced.

The blast furnace gas after power generation enters from the lower part of the absorption tower and is firstly contacted with first and second layers of circulating water in the tower, the circulating water plays a role in spraying and cooling to ensure that a large amount of hydrogen sulfide gas is dissolved into a liquid phase, the third layer is 10-30% alkali liquor, and the hydrogen sulfide dissolved into the liquid phase is mainly contacted with the layer of spraying liquid to react to generate sodium sulfide and sodium hydrosulfide. The purified blast furnace gas enters two layers of demisters in the tower to remove moisture carried in the gas and ensure that the mechanical water content is less than 7g/Nm3 when the gas enters a pipe network. The low-concentration absorption liquid at the bottom of the absorption tower enters the circulating water tank in a self-flowing mode, and is sent back to the absorption tower through the circulating water pump for recycling. Meanwhile, the process water is used for backwashing the demister periodically, so that the demister is prevented from scaling and the demisting efficiency is prevented from being influenced.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.