CN216614549U

CN216614549U - Blast furnace gas desulfurization and dechlorination purification device

Info

Publication number: CN216614549U
Application number: CN202122565811.4U
Authority: CN
Inventors: 史家乐; 刘斌斌; 樊琼
Original assignee: Xi'an Xikuang Environmental Protection Co ltd
Current assignee: Xi'an Longjing Environmental Protection Technology Co ltd
Priority date: 2021-10-25
Filing date: 2021-10-25
Publication date: 2022-05-27
Anticipated expiration: 2031-10-25

Abstract

The utility model discloses a desulfurization and dechlorination purification device for blast furnace gas, which comprises an ammonia spraying tower, a catalytic oxidation tower, a catalyst regeneration tower, a desulfurization tower, a regeneration tower, a hot blast stove, a sulfur foam tank, a sulfur melting kettle, a process water tank, a gas storage tank, a waste water tank, an ammonia storage tank and a sulfur storage tank, wherein the blast furnace gas is introduced into one side of the ammonia spraying tower, one path of the other side of the ammonia spraying tower is connected with the catalyst regeneration tower, the other path of the ammonia spraying tower is connected with the catalytic oxidation tower, the catalytic oxidation tower is sequentially connected with the desulfurization tower, the regeneration tower and the sulfur foam tank, the catalyst regeneration tower is connected with the catalytic oxidation tower, the ammonia spraying tower is also connected with the desulfurization tower, one side of the process water tank is connected with the ammonia spraying tower, the other side of the process water tank is connected with the desulfurization tower, the desulfurization tower is also connected with the gas storage tank, the hot blast furnace is connected between the desulfurization tower and the gas storage tank, and the waste water tank is respectively connected with the ammonia spraying tower, the catalytic oxidation tower, the desulfurization tower and the regeneration tower, the regeneration tower is connected with an air compressor, the ammonia storage tank is connected between the ammonia spraying tower and the desulfurization tower, and the sulfur storage tank is respectively connected with the catalytic oxidation tower and the catalyst regeneration tower.

Description

Blast furnace gas desulfurization dechlorination purifier

Technical Field

The utility model belongs to the technical field of pollutant control in the field of metallurgical industry, and particularly relates to a desulfurization and dechlorination purification device for blast furnace gas.

Background

In 2019, the yield of the crude steel in China is 9.96 hundred million tons, the yield is increased by 8.3 percent on year-on-year basis, the high-speed increase proportion of the yield accounts for 54 percent of the whole world, and about 1700-2000 m can be produced by producing one ton of crude steel³The pressure of the top furnace gas is (1.5-2.0) x 10⁵Pa, the pressure corresponding to 100kJ/m³The thermal energy of (2). The traditional blast furnace gas dust removal adopts a wet water washing technology, and the technology can also remove a large amount of acid gas. With the continuous innovation of the technology, the blast furnace gas dry dedusting technology becomes the mainstream technology of the current steel mills, and the originally unobvious acid gas is highlighted as an environmental problem again, such as H₂S、SO₂Gaseous corrosive substances such as HCl and the like and other very tiny solid corrosive substances still remain in the clean gas, and when the ambient temperature is lower than the dew point or moisture is brought into the gas by other processes, the corrosive substances in the gas are dissolved in condensed water, so that the pipe network and equipment are greatly damaged.

The sulfur content in the blast furnace gas mainly comprises COS and CS₂And H₂S, wherein COS and CS₂In a concentration of 70% of the total sulfur (CS)₂Very small content), H₂The S concentration is 30% of the total sulfur. Therefore, the sulfur content in the blast furnace gas is mainly COS, and the concentration is 100-³Albeit in blast furnace gasThe sulfur content is low, but with the promulgation of the opinion about the promotion of ultralow emission in the steel industry, SO in the flue gas after combustion₂Cannot meet the ultra-low emission limits.

Meanwhile, the concentration of chloride ions in the blast furnace gas is as high as 100-300 mg/m³The technical guideline for ultra-low emission modification of iron and steel enterprises issued by the middle-ring coordination proposes that a blast furnace gas purification system is suitable to be matched with a deacidification device, and H is purified₂The S concentration is preferably less than 10mg/m³”。

The current blast furnace gas desulfurization mode comprises front-end gas treatment and tail-end gas treatment, if tail-end gas treatment is adopted, a gas desulfurization station needs to be built near a kiln, and if the number of kilns is large and the kilns are dispersed, the construction cost is increased and the management is inconvenient; meanwhile, the desulfurization byproduct is gypsum, so that the commercial value is low and even the desulfurization byproduct is not recycled, and the problem of environmental pollution is caused; in addition, SCR denitration technique is adopted to present terminal flue gas denitration more, and SO2 that exists in the flue gas can produce huge influence to the denitration catalyst, reduces the life of catalyst, increases the replacement cost. If front-end gas treatment is adopted, the gas desulfurization station can be planned in the gas station, so that overall management is facilitated and the operation cost is saved; meanwhile, the gas desulfurizer can be repeatedly recycled, and a desulphurization byproduct is elemental sulfur, so that the commercial value is high and no pollutant is generated; in addition, the denitration can adopt more economic low temperature denitration catalyst, very big reduction terminal waste gas treatment cost.

The blast furnace gas contains 12 percent of CO₂Removal of H by calcium method₂S, about 3000ppm of H in blast furnace gas₂S and 12% CO₂When reacting with alkali liquor, the absorption ratio of the two is 1: 4-1: 12, a large amount of alkali liquor is wasted, the operation cost is increased, and the reaction temperature and the pH value need to be controlled in the reaction process, so that the operation is complex. In addition, the products of the alkali liquor absorption method are NaHS and NaHCO₃Addition of recycling apparatus, and NaHS and NaHCO₃The recovery difficulty is high, and secondary pollution is easy to cause.

The technology of desulfurization and dechlorination of blast furnace gas is a new research direction, and the research at home and abroad aiming at the technology of desulfurization and dechlorination of blast furnace gas only has stage achievements, does not form a complete technical process route, is lack of fine desulfurization equipment of blast furnace gas and cannot support engineering application.

SUMMERY OF THE UTILITY MODEL

In view of the above, the main object of the present invention is to provide a desulfurization and dechlorination purification device for blast furnace gas.

In order to achieve the purpose, the technical scheme of the utility model is realized as follows:

the embodiment of the utility model provides a desulfurization and dechlorination purification device for blast furnace gas, which comprises an ammonia spraying tower, a catalytic oxidation tower, a catalyst regeneration tower, a desulfurization tower, a regeneration tower, a hot blast stove, a sulfur foam tank, a sulfur melting kettle, a process water tank, a gas storage tank, a wastewater tank, an ammonia storage tank and a sulfur storage tank, wherein the blast furnace gas is introduced into one side of the ammonia spraying tower, one path of the other side of the ammonia spraying tower is connected with the catalyst regeneration tower, the other path of the ammonia spraying tower is connected with the catalytic oxidation tower, the catalytic oxidation tower is sequentially connected with the desulfurization tower, the regeneration tower and the sulfur foam tank, the catalyst regeneration tower is connected with the catalytic oxidation tower, the ammonia spraying tower is also connected with the desulfurization tower, one side of the process water tank is connected with the ammonia spraying tower, the other side of the process water tank is connected with the desulfurization tower, the desulfurization tower is also connected with the gas storage tank, the hot blast furnace is connected between the desulfurization tower and the gas storage tank, and the wastewater tank is respectively connected with the ammonia spraying tower, the catalytic oxidation tower, the desulfurization tower, The regeneration tower is connected with an air compressor, the ammonia storage tank is connected between the ammonia spraying tower and the desulfurizing tower, and the sulfur storage tank is respectively connected with the catalytic oxidation tower and the catalyst regeneration tower.

In the above scheme, the tower body of the ammonia spraying tower is provided with a first inlet flue, a first outlet flue, a first demister flushing water spraying layer, a first demister, a first ammonia water spraying layer, a first water sealing unit, a first emergency liquid discharge port, a first ammonia water circulating port, a first liquid collecting tank and a first waste liquid discharge port;

the first inlet flue is positioned below the side surface of the tower body and is used for feeding blast furnace gas into the ammonia spraying tower;

the first outlet flue is positioned at the top of the tower body and used for feeding the blast furnace gas subjected to the temperature reduction of the mixed ammonia into the catalytic oxidation tower;

the first demister is positioned in the middle of the tower body and is used for removing a large amount of open water carried in blast furnace gas;

the first demister washing water spraying layer is positioned on the upper side of the first demister and used for regularly washing the demister;

the first ammonia water spraying layers are arranged in multiple layers and are positioned on the lower side of the first demister, and each layer of the first ammonia water spraying layer is connected with the gas storage tank, is used for spraying ammonia water, is connected with the process water tank and is used for periodically flushing a spraying pipeline and a nozzle;

the first water seal unit is positioned at the lower side in the tower body and used for separating the tower body from the first liquid collecting tank, and a densimeter and a liquid level monitoring system are arranged at the same time for monitoring the density and the liquid level of the waste liquid in real time;

the first liquid collecting tank is positioned at the bottom of the tower body;

the first emergency liquid discharge port and the first liquid discharge port are positioned at the lower side of the first water seal unit and are used for introducing waste liquid into the first liquid collecting tank when the liquid level is higher than the liquid level for monitoring;

the first ammonia water circulating port is positioned below one side of the tower body and used for circularly pumping the ammonia-containing rich liquid to the first ammonia water spraying layer;

the first waste liquid outlet is arranged below the other side of the tower body and used for discharging ammonia-containing lean liquid to the waste water tank to extract ammonium salt.

In the scheme, the tower body of the catalytic oxidation tower is provided with a first blast furnace gas inlet, a first blast furnace hot gas inlet, a first catalyst feed inlet, a second catalyst feed inlet, a first catalyst discharge outlet, a second catalyst discharge outlet, a first catalyst support net, a second catalyst support net, a first hot gas outlet and a first sulfur discharge outlet;

the first blast furnace gas inlet is positioned below one side of the tower body, is connected with a first outlet flue of the ammonia spraying tower and is used for feeding blast furnace gas into the catalytic oxidation tower;

the first blast furnace hot gas inlet is positioned at the top of the tower body, is connected with the hot blast stove and is used for inputting high-temperature hot gas;

the first catalyst feeding port and the first catalyst discharging port are respectively arranged at two opposite sides of the upper part of the tower body, and a first catalyst supporting net is arranged at the position in the tower body and used for feeding and discharging;

the second catalyst feeding port and the second catalyst discharging port are respectively arranged at two opposite sides of the lower part of the tower body, and a second catalyst supporting net is arranged at the position in the tower body and used for feeding and discharging;

the first hot gas outlet is positioned at the upper part of one side, is connected with the desulfurization tower and is used for feeding the blast furnace gas subjected to organic sulfur removal into the desulfurization tower;

the first sulfur discharge port is positioned at the bottom of the tower body and connected with a sulfur storage tank for recovering liquid sulfur.

In the above scheme, the tower body of the catalyst regeneration tower is provided with a second blast furnace gas inlet, a second blast furnace hot gas inlet, a third catalyst feed inlet, a fourth catalyst feed inlet, a third catalyst discharge outlet, a fourth catalyst discharge outlet, a third catalyst support net, a fourth catalyst support net, a second hot gas outlet, and a second sulfur discharge outlet;

the second blast furnace gas inlet is positioned below one side of the tower body, is connected with the first outlet flue of the ammonia spraying tower and is used for feeding the blast furnace gas into the catalyst regeneration tower;

the second blast furnace hot gas inlet is positioned at the top of the tower body, is connected with the hot blast stove and is used for inputting high-temperature hot gas;

the third catalyst feeding port and the third catalyst discharging port are respectively arranged at two opposite sides of the upper part of the tower body, and a third catalyst supporting net is arranged at the position in the tower body and used for feeding and discharging;

the fourth catalyst feeding port and the fourth catalyst discharging port are respectively arranged at two opposite sides of the lower part of the tower body, and a fourth catalyst supporting net is arranged at the position in the tower body and used for feeding and discharging;

the second hot gas outlet is positioned at the upper part of one side of the tower body, is connected with the desulfurization tower and is used for feeding the blast furnace gas subjected to organic sulfur removal into the desulfurization tower;

and the second sulfur discharge port is positioned at the bottom of the tower body and is connected with a sulfur storage tank for recovering liquid sulfur.

In the above scheme, the tower body of the desulfurization tower is provided with a second inlet flue, a second outlet flue, a second demister flushing water spray layer, a second demister, a second ammonia water spray layer, a second water seal unit, a second emergency liquid discharge port, a second waste liquid discharge port, a second liquid collecting tank and a waste liquid regeneration port;

the second inlet flue is positioned below the side surface of the tower body and is used for feeding the blast furnace gas subjected to organic sulfur removal into the desulfurization tower;

the second outlet flue is positioned at the top of the tower body and used for conveying the purified and cleaned blast furnace gas to a downstream gas pipe network;

the second demister is positioned in the middle of the tower body and is used for removing a large amount of open water carried in blast furnace gas;

the second demister washing water spraying layer is positioned on the upper side of the second demister and is used for regularly washing the demister;

the second ammonia spraying layers are arranged in multiple layers and are positioned on the lower side of the second demister, each second ammonia spraying layer is connected with the gas storage tank, is used for spraying ammonia water, is connected with the process water tank, is used for periodically washing a spraying pipeline and a nozzle, and meets the coverage rate of 200-300%;

the second water seal unit is positioned at the lower side in the tower body and used for separating the tower body from a second liquid collecting tank, and a densimeter and a liquid level monitoring system are arranged at the same time for monitoring the density and the liquid level of the waste liquid in real time;

the second liquid collecting tank is positioned at the bottom of the tower body;

the second emergency liquid discharge port and the second liquid discharge port are positioned on the lower side of the second water seal unit and are used for introducing waste liquid into a second liquid collecting pool when the liquid level is higher than the liquid level monitoring;

the second waste liquid outlet is arranged below one side of the tower body and used for discharging ammonia-containing lean liquid to a waste water tank to extract ammonium salt;

the waste liquid regeneration port is arranged below the other side of the tower body and used for sending the waste liquid into the regeneration tower.

In the scheme, the tower body of the regeneration tower is provided with a liquid inlet, an air inlet, a liquid level regulator, a sulfur foam overflow port and a third waste liquid discharge port;

the liquid inlet is arranged below one side of the tower body, is connected with a waste liquid regeneration port of the desulfurization tower and is used for conveying the desulfurization waste liquid to the regeneration tower;

the air inlet is arranged below the other side of the tower body, is connected with an air compressor and is used for blowing compressed air to regenerate the desulfurization circulating liquid;

the liquid level regulator is arranged above one side of the tower body, is connected with a second ammonia spray layer of the desulfurization tower and is used for enabling the desulfurization circulating liquid after the regeneration reaction to enter the desulfurization tower from the top end of the regeneration tower in a self-flowing mode for continuous recycling;

the sulfur foam overflow port is arranged above the tower body and is connected with the sulfur foam tank and the sulfur melting kettle;

and the third waste liquid discharge port is arranged below the other side of the tower body and is used for discharging waste liquid to the waste water tank.

In the scheme, a blast furnace gas inlet valve, a first induced draft fan and an ammonia spraying tower gas inlet valve are sequentially arranged between the blast furnace gas and a first inlet flue of the ammonia spraying tower;

a gas outlet valve of the ammonia spraying tower, a second induced draft fan, a first gas inlet valve of the catalytic oxidation tower and a first blast furnace gas inlet of the catalytic oxidation tower are sequentially arranged between a first outlet flue of the ammonia spraying tower and the first blast furnace gas inlet of the catalytic oxidation tower;

a gas outlet valve of the ammonia spraying tower, a third induced draft fan and a second gas inlet valve of the catalytic oxidation tower are sequentially arranged between the first outlet flue of the ammonia spraying tower and the second gas inlet of the catalyst regeneration tower and are connected with the second gas inlet of the catalyst regeneration tower;

an inlet valve of a washing water spraying layer of the ammonia spraying tower and a first water feeding pump are sequentially arranged between a washing water spraying layer of a first demister of the ammonia spraying tower and a process water tank;

the multi-layer first ammonia water spraying layer of the ammonia spraying tower is respectively connected between the inlet valve of the ammonia spraying tower flushing water spraying layer and the first water supply pump through the ammonia spraying tower flushing water inlet valve of the spraying layer;

one path of the ammonia storage tank passes through an outlet valve of the ammonia storage tank and then is connected with a first ammonia water circulation port of the ammonia spraying tower through an ammonia supply pump, a main control valve of an ammonia water spraying layer of the ammonia spraying tower, an ammonia water circulation control valve of the ammonia spraying tower and an ammonia water circulation outlet valve of the ammonia spraying tower of the ammonia water circulation pump;

the multi-layer first ammonia water spraying layer of the ammonia spraying tower is also respectively connected between the main control valve of the ammonia water spraying layer of the ammonia spraying tower and the ammonia water circulation control valve of the ammonia spraying tower through an inlet valve of the ammonia spraying layer of the ammonia spraying tower;

and a first waste liquid discharge port of the ammonia spraying tower is connected with a waste water tank through a waste water outlet valve of the ammonia spraying tower, a liquid discharge pump and a waste water inlet valve.

In the scheme, a gas outlet valve of the catalytic oxidation tower is arranged on a first hot gas outlet of the catalytic oxidation tower;

a second hot coal gas outlet of the catalyst regeneration tower is provided with a coal gas outlet valve of the catalyst regeneration tower;

the catalytic oxidation tower coal gas outlet valve is connected with the catalyst regeneration tower coal gas outlet valve, and a catalytic regeneration coal gas control valve is arranged between the catalytic oxidation tower coal gas outlet valve and the catalyst regeneration tower coal gas outlet valve;

one side of the catalytic oxidation tower gas outlet main control valve is connected between the catalytic regeneration gas control valve and the catalytic oxidation tower gas outlet valve, and the other side of the catalytic oxidation tower gas outlet main control valve is connected with a second inlet flue of the desulfurizing tower through a fourth induced draft fan and a desulfurizing tower gas inlet valve;

a first hot gas inlet valve is arranged on the first blast furnace hot gas inlet, a second hot gas inlet valve is arranged on the second blast furnace hot gas inlet, and the first hot gas inlet valve and the second hot gas inlet valve are connected and then connected with the hot blast stove through a hot blast stove outlet valve and a fifth induced draft fan;

a first sulfur discharge port at the bottom of the catalytic oxidation tower is connected with a sulfur storage tank through a sulfur discharge port valve of the catalytic oxidation tower, a sulfur discharge pump and a tower liquid sulfur inlet valve;

and a second sulfur discharge port of the catalyst regeneration tower is connected between a sulfur discharge port valve of the catalytic oxidation tower and a sulfur discharge pump through a sulfur discharge port valve of the catalyst regeneration tower.

In the scheme, after a second outlet flue of the desulfurizing tower is connected with a desulfurizing tower gas outlet valve and a sixth induced draft fan, one path of the second outlet flue is connected with a blast furnace gas outlet through the blast furnace gas outlet valve, and the other path of the second outlet flue is connected with a hot blast stove through a hot blast stove inlet valve;

each layer of second ammonia water spraying layer of the desulfurizing tower is connected with a desulfurizing tower ammonia water spraying layer master control valve of an ammonia storage tank through a desulfurizing tower ammonia water spraying layer inlet valve respectively, a desulfurizing tower ammonia supply pump is arranged between the desulfurizing tower ammonia water spraying layer master control valve and the plurality of layers of second ammonia water spraying layers, and the desulfurizing tower ammonia supply pump is connected to the other path of the ammonia storage tank outlet valve through the desulfurizing tower ammonia water spraying inlet valve;

each second ammonia spraying layer of the desulfurizing tower is also connected with a second water feeding pump of the process water tank through a flushing water inlet valve of the sulfur tower spraying layer, and a second outlet valve of the process water tank is arranged between the second water feeding pump and the process water tank;

the second waste liquid discharge port of the desulfurizing tower is connected with a liquid discharge pump through a desulfurizing tower waste water outlet valve and a desulfurizing tower waste water control valve;

and a waste liquid regeneration port of the desulfurizing tower is connected with a liquid inlet of the regenerating tower through a regenerated waste liquid outlet valve of the desulfurizing tower, a waste liquid conveying pump and a regenerated waste liquid inlet valve of the regenerating tower.

And a second demister flushing water spraying layer of the desulfurizing tower is connected with a second water feeding pump through a desulfurizing tower flushing water spraying layer inlet valve.

In the scheme, a liquid level regulator of the regeneration tower is connected between a main control valve of an ammonia water spraying layer of the desulfurization tower and an ammonia supply pump of the desulfurization tower through a desulfurization circulating liquid reflux pump and an outlet valve of the liquid level regulator;

a sulfur foam overflow port of the regeneration tower is connected with a sulfur foam tank through a sulfur foam overflow port valve and a sulfur foam tank inlet valve;

an air inlet of the regeneration tower is connected with an air compressor through an oxidation air inlet valve of the regeneration tower and an oxidation air outlet valve of the air compressor;

a third waste liquid discharge port of the regeneration tower is connected with a liquid discharge pump through a regeneration tower waste liquid outlet valve and a regeneration tower waste water control valve;

and the sulfur foam groove outlet of the sulfur foam groove is connected with the sulfur melting kettle through a sulfur foam groove outlet valve, a sulfur foam pump and a sulfur melting kettle inlet valve.

Compared with the prior art, the utility model solves the problem of the SO of the downstream user from the source₂The problem of exceeding standard is solved, the sulfur content in the coal gas is reduced, the rear-end flue gas treatment pressure is greatly reduced, even flue gas treatment equipment is omitted, the pollutant control cost of downstream users is reduced, and the problem of corrosion of a coal gas pipeline is controlled to a certain extent.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiment(s) of the utility model and together with the description serve to explain the utility model without limiting the utility model. In the drawings:

FIG. 1 is a schematic structural diagram of a blast furnace gas desulfurization and dechlorination purification device according to an embodiment of the present invention;

FIG. 2 is a schematic view of a valve arrangement structure of a gas desulfurization, dechlorination and purification apparatus for a blast furnace according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not intended to limit the utility model.

The same or similar reference numerals in the drawings of the present embodiment correspond to the same or similar components; in the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, the terms describing the positional relationships in the drawings are only for illustrative purposes and are not to be construed as limitations of the present patent, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, article, or apparatus that comprises the element.

The embodiment of the utility model provides a desulfurization and dechlorination purification device for blast furnace gas, which comprises an ammonia spraying tower 1, a catalytic oxidation tower 2, a catalyst regeneration tower 3, a desulfurization tower 4, a regeneration tower 5, a hot blast stove 6, a sulfur foam tank 7, a sulfur melting kettle 8, a process water tank 9, a gas storage tank 10, a wastewater tank 11, an ammonia storage tank 12 and a sulfur storage tank 13, wherein blast furnace gas is introduced into one side of the ammonia spraying tower 1, one path of the other side of the ammonia spraying tower is connected with the catalyst regeneration tower 3, the other path of the ammonia spraying tower is connected with the catalytic oxidation tower 2, the catalytic oxidation tower 2 is sequentially connected with the desulfurization tower 4, the regeneration tower 5 and the sulfur foam tank 7, the catalyst regeneration tower 3 is connected with the catalytic oxidation tower 2, the ammonia spraying tower 1 is further connected with the desulfurization tower 4, one side of the process water tank 9 is connected with the ammonia spraying tower 1, the other side of the desulfurization tower 4 is further connected with the gas storage tank 10, the gas storage tank 6 is connected between the desulfurization tower 4 and the gas storage tank 10, waste water tank 11 is connected with ammonia spraying tower 1, catalytic oxidation tower 2, desulfurizing tower 4, regenerator 5 respectively, regenerator 5 is connected with air compressor machine 501, ammonia storage tank 12 is connected between ammonia spraying tower 1 and desulfurizing tower 4, sulfur storage tank 13 is connected with catalytic oxidation tower 2, catalyst regenerator 3 respectively.

The process water tank 9 is connected with the ammonia spraying tower 1 and the desulfurizing tower 4 and is used for sending washing water into the ammonia spraying tower 1 and the desulfurizing tower 4;

the waste water tank 11 is connected with the ammonia spraying tower 1 and the desulfurizing tower 4 and is used for recovering flushing water and partial waste liquid from the ammonia spraying tower 1 and the desulfurizing tower 4;

the ammonia storage tank 12 is connected with the ammonia spraying tower 1 and the desulfurizing tower 4 and is used for supplying ammonia water to provide an ammonia environment and removing inorganic sulfur;

the sulfur storage tank 13 is connected with the catalytic oxidation tower 2 and the catalyst regeneration tower 3 and is used for recovering sulfur elementary substances flowing out of the catalytic oxidation tower 2 and the catalyst regeneration tower 3;

the blast furnace gas from a turbine system is sent into the ammonia spraying tower 1, and because the temperature of the blast furnace gas at the outlet of the turbine is about 65 ℃, the suitable temperature for catalytic oxidation of organic sulfur is about 35 ℃ and an ammonia environment is needed, the ammonia spraying tower mainly has the functions of cooling the blast furnace gas, providing an ammonia environment for subsequent processes and removing partial inorganic sulfur and Cl elements;

the catalytic oxidation tower 2 and the catalyst regeneration tower 3 have the same structure and can mutually convert functions, one tower plays a role in catalytically oxidizing COS into elemental sulfur, and the other tower plays a role in recovering the elemental sulfur;

the desulfurizing tower 4 is connected to the rear end of the catalytic oxidation tower 2 and is used for removing inorganic sulfur and Cl elements in the blast furnace gas; the regeneration tower 5 is connected to the rear end of the desulfurization tower 4 and is used for regenerating ammonia water and preparing finished sulfur paste; the purified clean blast furnace gas is sent into a gas storage tank 10 for storage or is sent into a blast furnace gas pipe network;

the ammonia water with the mass fraction of 25-28% is mainly contained in the ammonia storage tank 12, wherein the molar ratio of the ammonia content in the ammonia water to the pollutants is controlled to be 2.0-3.0, so that the high-efficiency removal of organic sulfur, inorganic sulfur and Cl elements in blast furnace gas is ensured.

The tower body of the ammonia spraying tower 1 is provided with a first inlet flue 101, a first outlet flue 102, a first demister flushing water spraying layer 103, a first demister 104, a first ammonia water spraying layer 105, a first water sealing unit 106, a first emergency liquid discharging port 107, a first liquid discharging port 108, a first ammonia water circulating port 109, a first liquid collecting tank 110 and a first waste liquid discharging port 111;

the first inlet flue 101 is positioned below the side surface of the tower body and is used for feeding blast furnace gas into the ammonia injection tower 1;

the first outlet flue 102 is positioned at the top of the tower body and is used for feeding the blast furnace gas subjected to the temperature reduction of the mixed ammonia into the catalytic oxidation tower 2;

the first demister 104 is positioned in the middle of the tower body and is used for removing a large amount of open water carried in blast furnace gas;

the first demister washing water spraying layer 103 is positioned on the upper side of the first demister 104 and is used for periodically washing the demister 104;

the first ammonia water spraying layer 105 is provided with a plurality of layers and is positioned at the lower side of the first demister 104, and each layer of the first ammonia water spraying layer 105 is connected with the ammonia storage tank 12 and used for spraying ammonia water, is connected with the process water tank 9 and used for periodically flushing a spraying pipeline and a nozzle;

the first water seal unit 106 is positioned at the lower side in the tower body, is used for separating the tower body from the first liquid collecting tank 110, and is provided with a densimeter and a liquid level monitoring system for monitoring the density and the liquid level of the waste liquid in real time;

the first liquid collecting tank 110 is positioned at the bottom of the tower body;

the first emergency drain port 107 and the first drain port 108 are positioned at the lower side of the first water seal unit 106 and are used for introducing waste liquid into the first liquid collecting tank 110 when the liquid level is higher than the liquid level for monitoring;

the first ammonia water circulating port 109 is positioned below one side of the tower body and is used for circularly pumping the ammonia-containing rich liquid to the first ammonia water spraying layer 105;

the first waste liquid outlet 111 is arranged below the other side of the tower body and is used for discharging ammonia-containing lean liquid to the waste water tank 11 to extract ammonium salt.

The ammonia water in the ammonia spraying tower 1 is industrial ammonia water with the concentration of 25-28%, the flow velocity of the cross section in the tower is below 4m/s, so that the blast furnace gas can stay in the tower for a sufficient time, the stay time is generally above 5s, and the temperature of the blast furnace gas outlet is preferably 35 ℃.

The tower body of the catalytic oxidation tower 2 is provided with a first blast furnace gas inlet 201, a first blast furnace hot gas inlet 202, a first catalyst inlet 203, a second catalyst inlet 204, a first catalyst discharge opening 205, a second catalyst discharge opening 206, a first catalyst support screen 207, a second catalyst support screen 208, a first hot gas outlet 209 and a first sulfur discharge opening 210;

the first blast furnace gas inlet 201 is positioned below one side of the tower body, is connected with the first outlet flue 102 of the ammonia spraying tower 1, and is used for feeding blast furnace gas into the catalytic oxidation tower 2;

the first blast furnace hot gas inlet 202 is positioned at the top of the tower body, is connected with the hot blast stove 6 and is used for inputting high-temperature hot gas;

the first catalyst feeding port 203 and the first catalyst discharging port 205 are respectively arranged at two opposite sides of the upper part of the tower body, and a first catalyst supporting net 207 is arranged at the position in the tower body and used for feeding and discharging;

the first catalyst support screen 207 is used to support a catalyst;

the second catalyst feeding hole 204 and the second catalyst discharging hole 206 are respectively arranged at two opposite sides of the lower part of the tower body, and a second catalyst supporting net 208 is arranged in the tower body and used for feeding and discharging;

the second catalyst support screen 208 is used to support a catalyst;

the first hot gas outlet 209 is positioned at the upper part of one side, is connected with the desulfurization tower 4, and is used for feeding the blast furnace gas from which organic sulfur is removed into the desulfurization tower 4;

the first sulfur discharge port 210 is located at the bottom of the tower body, is connected with the sulfur storage tank 13, and is used for draining the analyzed elemental sulfur into the sulfur storage tank 13 for collection.

The tower body of the catalyst regeneration tower 3 is provided with a second blast furnace gas inlet 301, a second blast furnace hot gas inlet 302, a third catalyst inlet 303, a fourth catalyst inlet 304, a third catalyst discharge outlet 305, a fourth catalyst discharge outlet 306, a third catalyst support screen 307, a fourth catalyst support screen 308, a second hot gas outlet 309 and a second sulfur discharge outlet 310;

the second blast furnace gas inlet 301 is positioned below one side of the tower body, is connected with the first outlet flue 102 of the ammonia spraying tower 1, and is used for feeding blast furnace gas into the catalyst regeneration tower 3;

the second blast furnace hot gas inlet 302 is positioned at the top of the tower body, is connected with the hot blast stove 6 and is used for inputting high-temperature hot gas;

the third catalyst feed port 303 and the third catalyst discharge port 305 are respectively arranged at two opposite sides of the upper part of the tower body, and a third catalyst support net 307 is arranged at the position in the tower body and used for feeding and discharging;

the third catalyst support net 307 is used for supporting a catalyst;

the fourth catalyst feed inlet 304 and the fourth catalyst discharge outlet 306 are respectively arranged at two opposite sides of the lower part of the tower body, and a fourth catalyst support net 308 is arranged in the tower body and used for feeding and discharging;

the fourth catalyst support screen 308 is used to support a catalyst;

the second hot gas outlet 309 is positioned at the upper part of one side of the tower body, is connected with the desulfurization tower 4, and is used for feeding the blast furnace gas subjected to organic sulfur removal into the desulfurization tower 4;

the second sulfur discharge port 310 is located at the bottom of the tower body, is connected with the sulfur storage tank 13, and is used for draining the analyzed elemental sulfur into the sulfur storage tank 13 for collection.

The catalytic oxidation tower 2 and the catalyst regeneration tower 3 work alternately, one tower is responsible for catalytic oxidation of COS to elemental sulfur, and the other tower is responsible for resolving the elemental sulfur;

sending the cooled blast furnace gas into a catalytic oxidation tower 2; under the action of ammonia and oxygen, most S elements in the COS in the blast furnace gas generate elemental sulfur, a small amount of the COS generates ammonium sulfate, the elemental sulfur and the ammonium sulfate are adsorbed on the surface of the catalyst, and the blast furnace gas from which the organic sulfur is removed enters the next working procedure from a blast furnace gas outlet 208.

The catalyst regeneration tower 3 is connected with a hot blast stove 6, when enough elemental sulfur and ammonium sulfate are adsorbed on the surface of the catalyst, hot coal gas with the temperature of more than 450 ℃ is led out from an outlet of the hot blast stove through a draught fan and enters the catalytic reactor through a hot coal gas inletA catalyst regeneration tower 3; the boiling point of the sulfur simple substance is 444.6 ℃, the sulfur simple substance is converted into sulfur steam through high temperature, and simultaneously the ammonium sulfate is decomposed into NH under the high temperature condition₃、N₂、SO₂And steam, wherein the flue gas after desorption is sulfur-rich gas; the temperature of the flue gas is reduced to 130-160 ℃ through a condenser, and the elemental sulfur steam can be liquefied into liquid sulfur; at the moment, the liquid sulfur has the lowest viscosity and the best liquidity, flows to the bottom of the tower along with the pipeline, and enters the sulfur storage tank 13 through the second sulfur discharge port 310; the temperature of the sulfur-containing gas after the liquid sulfur is separated is kept between 80 ℃ and 100 ℃, and part of the sulfur-containing gas is heated to 450 ℃ through a heating furnace, so that heat can be supplied to the steps; the other part of the sulfur-containing gas is continuously cooled to 25-35 ℃ through a condenser, and the residual desorption gas and the blast furnace gas are mixed and sent into a desulfurizing tower.

The catalytic oxidation tower 2 is also used in the same manner.

Wherein the catalyst is one of a rod, a sphere and a Raschig ring, and is added in NH₃And O₂In the same environment, COS in the blast furnace gas is catalytically oxidized into elemental sulfur and ammonium sulfate crystals and adsorbed; the catalyst carrier is one of active carbon, alumina and hydrotalcite-like compound; the catalyst is randomly stacked on the catalyst support net, and the reaction airspeed of the catalyst is 500-2000 h^-1The density is 0.65 to 0.7t/m³The gas flow rate is 1-3 m/s.

The tower body of the desulfurizing tower 4 is provided with a second inlet flue 401, a second outlet flue 402, a second demister flushing water spraying layer 403, a second demister 404, a second ammonia water spraying layer 405, a second water sealing unit 406, a second emergency liquid discharging port 407, a second liquid discharging port 408, a second waste liquid discharging port 409, a second liquid collecting tank 410 and a waste liquid regenerating port 411;

the second inlet flue 401 is positioned below the side surface of the tower body and is used for feeding the blast furnace gas without organic sulfur into the desulfurizing tower 4;

the second outlet flue 402 is positioned at the top of the tower body and used for conveying the purified and cleaned blast furnace gas to a downstream gas pipe network;

the second demister 404 is positioned in the middle of the tower body and is used for removing a large amount of open water carried in the blast furnace gas;

the second demister washing water spraying layer 103 is positioned on the upper side of the second demister 404 and is used for periodically washing the demister 404;

the second ammonia water spraying layers 405 are arranged in multiple layers and are positioned on the lower side of the second demister 404, each layer of the second ammonia water spraying layer 405 is connected with the ammonia storage tank 12 and used for spraying ammonia water, is connected with the process water tank 9 and used for periodically washing the spraying pipelines and the nozzles, and the coverage rate of the second ammonia water spraying layers is 200-300%;

the second water seal unit 406 is positioned at the lower side in the tower body and used for separating the tower body from the second liquid collecting tank 410, and is also provided with a densimeter and a liquid level monitoring system for monitoring the density and the liquid level of the waste liquid in real time;

the second liquid collecting tank 410 is positioned at the bottom of the tower body;

the second emergency drain port 407 and the second drain port 408 are located at the lower side of the second water seal unit 406, and are used for introducing waste liquid into the second liquid collecting tank 410 when the liquid level is higher than the liquid level for monitoring;

the second waste liquid discharge port 409 is arranged below one side of the tower body and is used for discharging ammonia-containing lean liquid to the waste water tank 11 to extract ammonium salt;

the waste liquid regeneration port 411 is disposed below the other side of the tower body, and is used for sending waste liquid into the regeneration tower 5.

The blast furnace gas without organic sulfur is sent to a desulfurizing tower 4 to remove inorganic sulfur and Cl elements, a tower body in the middle of the desulfurizing tower 4 is provided with 4 layers of second ammonia water spraying layers 405 to meet the coverage rate of 200-300 percent, the ammonia water is in countercurrent contact with the blast furnace gas, and H in the gas₂S and SO₂Reacting with ammonia water to generate NH₄HS、(NH₄)₂S、(NH₄)₂SO₃、NH₄Cl and other substances are dissolved in the wastewater and flow to a second water sealing unit 406 at the bottom of the desulfurizing tower 4, and the purified blast furnace gas is sent into a gas storage tank 13 or a downstream gas pipe network through a second outlet flue 402 after part of the open water is removed by a second demister 404; the second washing water spray layer 103 is used for washing the second demister 404 to prevent scaling; the desulfurization wastewater is gathered in a water seal system which is provided with a densimeter and a liquidA level monitoring device, when the liquid level of the waste water reaches a certain height, a second liquid outlet 408 is opened, and the waste liquid is collected in a second liquid collecting pool 410; the sulfur-containing lean solution in the second liquid collecting tank 410 is sent into a waste liquid tank through a liquid discharge pump 124 to extract ammonium salt; the sulfur-containing rich liquid in the second liquid collecting tank 410 is sent to the regeneration tower 5 from the waste liquid regeneration port 411 by the waste liquid transfer pump 426 to perform the next process.

The flow rate of the coal gas of the desulfurizing tower 4 is controlled to be 0.5-4 m/s, the uniform distribution of the air flow is ensured, and the temperature of a blast furnace coal gas inlet is controlled to be 25-30 ℃.

The tower body of the regeneration tower 5 is provided with a liquid inlet 502, an air inlet 503, a liquid level regulator 504, a sulfur foam overflow port 505 and a third waste liquid outlet 506;

the liquid inlet 502 is arranged below one side of the tower body, is connected with a waste liquid regeneration port 411 of the desulfurizing tower 4 and is used for sending the desulfurizing waste liquid to the regenerating tower 5;

the air inlet 503 is arranged below the other side of the tower body, is connected with the air compressor 501 and is used for blowing compressed air to regenerate the desulfurization circulating liquid;

the liquid level regulator 504 is arranged above one side of the tower body, is connected with the second ammonia spray layer 405 of the desulfurizing tower 4, and is used for enabling the desulfurizing circulating liquid after the regeneration reaction to enter the desulfurizing tower 4 from the top end of the regeneration tower in a self-flowing mode for continuous recycling;

the sulfur foam overflow port 505 is arranged above the tower body and is connected with the sulfur foam tank 7 and the sulfur melting kettle 8;

the third waste liquid outlet 506 is arranged below the other side of the tower body and is used for discharging waste liquid to the waste water tank 11.

Catalyst such as PDS, HPF or 888 is put into a reaction tank at the bottom of the regeneration tower 5, then the desulfurization circulating liquid is pumped into the upper layer reaction tank by a circulating pump, compressed air is blown in by an air compressor 501 to regenerate the desulfurization circulating liquid, and redundant regeneration air is diffused from the top of the tower; under the action of catalyst in the regeneration process, the sulfur-containing pregnant solution and O₂Reacting to generate ammonia water, sulfur simple substance, ammonium sulfate and other substances; liquid level regulator at top end of regeneration tower for desulfurization circulating liquid after regeneration reaction504, and the overflow enters the desulfurizing tower 4 for continuous recycling in a self-flowing mode; the generated sulfuric acid foam can float on the expanded section at the top of the regeneration tower, and then automatically flows into the sulfur foam tank 7 in an overflowing manner, and finally is heated, clarified and separated through a heating steam coil; the rest clear solution is sent back to a reaction tank at the bottom of the regeneration tower 5, the floating sulfur foam is sent to a sulfur dissolving kettle 8 through a sulfur foam pump 703, and the rest desulfurization solution produced by a heating separation technology is sent to the reaction tank; continuously heating the sulfur foam to a molten sulfur state, and finally preparing the sulfur foam into a finished product sulfur paste; the waste liquid is sent into a waste water tank 11 from a clear liquid return port for centralized treatment.

Wherein, the waste water tank 11 is used for intensively treating the desulfurization waste liquid generated by the ammonia spraying tower 1, the desulfurization tower 4 and the regeneration tower 5; contain a large amount of PDS in the desulfurization waste liquid, the suspension sulphur, ammonium thiosulfate, volatile ammonia, materials such as ammonium thiocyanate and ammonium sulfate, the desulfurization waste liquid can be retrieved and draw the ammonium salt, and this both can solve the sulphuric acid waste liquid treatment problem, can produce the better industrial chemicals of quality again, through drawing ammonium thiocyanate and ammonium thiosulfate, make its desulfurization ability of recovering the desulfurization liquid promptly, reentrant desulfurization circulation system.

A blast furnace gas inlet valve 112, a first induced draft fan 113 and an ammonia spraying tower gas inlet valve 114 are sequentially arranged between the blast furnace gas and the first inlet flue 101 of the ammonia spraying tower 1;

a gas outlet valve 115 of the ammonia spraying tower, a second induced draft fan 116, a first gas inlet valve 117 of the catalytic oxidation tower and a first blast furnace gas inlet 201 of the catalytic oxidation tower 2 are sequentially arranged between a first outlet flue 102 of the ammonia spraying tower 1 and the first blast furnace gas inlet 201 of the catalytic oxidation tower 2;

a gas outlet valve 115 of the ammonia spraying tower, a third induced draft fan 118 and a second gas inlet valve 119 of the catalytic oxidation tower are sequentially arranged between the first outlet flue 102 of the ammonia spraying tower 1 and the second gas inlet 301 of the catalyst regeneration tower 3 and are connected with the second gas inlet 301 of the catalyst regeneration tower 3;

an inlet valve 120 of the ammonia spraying tower flushing water spraying layer and a first water feeding pump 121 are sequentially arranged between the first demister flushing water spraying layer 103 of the ammonia spraying tower 1 and the process water tank 9;

the multilayer first ammonia water spray layer 105 of the ammonia spray tower 1 is respectively connected between an inlet valve 120 of a washing water spray layer of the ammonia spray tower and a first water feed pump 121 through an inlet valve 122 of the washing water of the washing spray layer of the ammonia spray tower;

after passing through an outlet valve 1201 of the ammonia storage tank 12, one path of the ammonia storage tank passes through an ammonia supply pump 1202, an ammonia spraying tower ammonia water spraying layer master control valve 1203, an ammonia spraying tower ammonia water circulation control valve 1204 and an ammonia spraying tower ammonia water circulation outlet valve 1206 of an ammonia spraying tower 1205 and is connected with a first ammonia water circulation port 109 of the ammonia spraying tower 1;

the multiple first ammonia water spraying layers 105 of the ammonia spraying tower 1 are also respectively connected between an ammonia water spraying layer master control valve 1203 of the ammonia spraying tower and an ammonia water circulating control valve 1204 through an ammonia water spraying layer inlet valve 1207 of the ammonia spraying tower;

the first waste liquid outlet 111 of the ammonia spraying tower 1 is connected with the waste water tank 11 through the waste water outlet valve 123 of the ammonia spraying tower, the liquid discharge pump 124 and the waste water inlet valve 125.

A first hot gas outlet 209 of the catalytic oxidation tower 2 is provided with a catalytic oxidation tower gas outlet valve 211;

a second hot gas outlet 309 of the catalyst regeneration tower 3 is provided with a catalyst regeneration tower gas outlet valve 311;

the catalytic oxidation tower gas outlet valve 211 is connected with the catalyst regeneration tower gas outlet valve 311, and a catalytic regeneration gas control valve 312 is arranged between the catalytic oxidation tower gas outlet valve 211 and the catalyst regeneration tower gas outlet valve;

one side of the catalytic oxidation tower gas outlet master control valve 212 is connected between the catalytic regeneration gas control valve 312 and the catalytic oxidation tower gas outlet valve 210, and the other side of the catalytic oxidation tower gas outlet master control valve 212 is connected with a second inlet flue 401 of the desulfurizing tower 4 through a fourth induced draft fan 213 and a desulfurizing tower gas inlet valve 214;

a first hot gas inlet valve 215 is arranged on the first blast furnace hot gas inlet 202, a second hot gas inlet valve 314 is arranged on the second blast furnace hot gas inlet 302, and the first hot gas inlet valve 215 and the second hot gas inlet valve 314 are connected and then connected with the hot blast furnace 6 through a hot blast furnace outlet valve 216 and a fifth induced draft fan 217;

the first sulfur discharging port 210 at the bottom of the catalytic oxidation tower 2 is connected with the sulfur storage tank 13 through a sulfur discharging port valve 218 of the catalytic oxidation tower, a sulfur discharging pump 219 and a tower liquid sulfur inlet valve 220;

the second sulfur discharging port 310 of the catalyst regeneration tower 3 is connected between the sulfur discharging port valve 218 of the catalytic oxidation tower and the sulfur discharging pump 219 through the sulfur discharging port valve 315 of the catalyst regeneration tower.

A second outlet flue 402 of the desulfurizing tower 4 is connected with a desulfurizing tower gas outlet valve 412 and a sixth induced draft fan 413, one path of the second outlet flue is connected with a blast furnace gas outlet through a blast furnace gas outlet valve 414, and the other path of the second outlet flue is connected with a hot blast stove 6 through a hot blast stove inlet valve 415;

each layer of second ammonia water spraying layer 405 of the desulfurizing tower 4 is respectively connected with a desulfurizing tower ammonia water spraying layer master control valve 417 of the ammonia storage tank 12 through a desulfurizing tower ammonia water spraying layer inlet valve 416, a desulfurizing tower ammonia supply pump 418 is arranged between the desulfurizing tower ammonia water spraying layer master control valve 417 and the multilayer second ammonia water spraying layers 405, and the desulfurizing tower ammonia supply pump 418 is connected to the other path of the ammonia storage tank outlet valve 1201 through a desulfurizing tower ammonia water spraying inlet valve 419;

each layer of second ammonia water spray layer 405 of the desulfurizing tower 4 is also respectively connected with a second water supply pump 421 of the process water tank 9 through a sulfur tower spray layer flushing water inlet valve 420, and a process water tank second outlet valve 422 is arranged between the second water supply pump 421 and the process water tank 9;

the second waste liquid discharge port 409 of the desulfurizing tower 4 is connected with the liquid discharge pump 124 through a desulfurizing tower waste water outlet valve 423 and a desulfurizing tower waste water control valve 424;

the waste liquid regeneration port 411 of the desulfurizing tower 4 is connected with the liquid inlet 502 of the regenerating tower 5 through a desulfurizing tower regenerated waste liquid outlet valve 425, a waste liquid conveying pump 426 and a regenerating tower regenerated waste liquid inlet valve 427.

And the second demister washing water spraying layer 403 of the desulfurizing tower 4 is connected with a second water feeding pump 421 through a desulfurizing tower washing water spraying layer inlet valve 428.

The liquid level regulator 504 of the regeneration tower 5 is connected between a main control valve 417 of an ammonia water spraying layer of the desulfurizing tower and an ammonia supply pump 418 of the desulfurizing tower through a desulfurizing circulating liquid reflux pump 507 and a liquid level regulator outlet valve 508;

a sulfur foam overflow port 505 of the regeneration tower 5 is connected with a sulfur foam tank 7 through a sulfur foam overflow port valve 509 and a sulfur foam tank inlet valve 510;

an air inlet 503 of the regeneration tower 5 is connected with an air compressor 501 through a regeneration tower oxidation air inlet valve 511 and an air compressor oxidation air outlet valve 512;

a third waste liquid discharge port 506 of the regeneration tower 5 is connected with the liquid discharge pump 124 through a regeneration tower waste liquid outlet valve 513 and a regeneration tower waste water control valve 514;

the sulfur foam tank outlet 701 of the sulfur foam tank 7 is connected with the sulfur melting kettle 8 through a sulfur foam tank outlet valve 702, a sulfur foam pump 703 and a sulfur melting kettle inlet valve 704.

The utility model can simultaneously remove COS and H in the blast furnace gas₂S and removing Cl element synergistically; the method specifically comprises the following steps:

(1) blast furnace gas from the rear end of a turbine firstly enters an ammonia spraying tower 1 to be cooled, and ammonia gas required by the next procedure is mixed;

(2) the blast furnace gas mixed with ammonia enters a catalytic oxidation tower 2, and COS in the blast furnace gas is catalytically oxidized into elemental sulfur and a small amount of ammonium sulfate and is adsorbed by a catalyst;

(3) the blast furnace gas without organic sulfur enters a desulfurizing tower 4 to remove inorganic sulfur and Cl elements through the reaction with ammonia water;

(4) the clean blast furnace gas after desulfurization and dechlorination is sent to a gas storage tank 13 for storage or sent to a downstream blast furnace gas pipe network.

The ammonia injection tower 1 in the utility model has triple effects: (1) cooling the coal gas: the outlet temperature of the blast furnace gas at the rear end of the turbine is about 65 ℃, and the temperature of the blast furnace gas is reduced from 65 ℃ to 35 ℃ by adjusting the using amount of ammonia water so as to meet the suitable temperature of the catalyst. (2) Providing an ammonia environment for the adsorption and removal of organic sulfur: the process mainly utilizes the catalytic oxidation reaction of COS, and COS gas enters the surface of the carbon-based microcrystal material in the environment containing oxygen and ammonia gasOxidation reaction is carried out to generate sulfur simple substance and sulfate to realize the purpose of removing COS. Because the blast furnace gas does not contain ammonia gas, ammonia needs to be sprayed in advance, the concentration of the sprayed ammonia is about 2-3 times of that of organic sulfur, and the specific concentration is determined according to the carbon source of the blast furnace gas, the concentration of the organic sulfur and the concentration of Cl ions. (3) Auxiliary dechlorination: due to Cl ions and H₂The mutual influence of S gas can cause the corrosion of the pipeline, so that the ammonia water spraying can neutralize part of Cl ions in the blast furnace gas, and the effect of auxiliary dechlorination is achieved.

Under the condition of the same blast furnace capacity, the temperature of the coal gas after wet purification is generally about 50 ℃, the temperature of the coal gas after dry purification is between 120 and 230 ℃, the temperature difference between the two is generally about 70 to 180 ℃, the pressure loss is small, the resistance loss is generally 5kPa or even less, and therefore, the recovery power of the dry TRT can be improved by 30 to 40 percent compared with that of the wet TRT. The whole process is arranged at the rear end of the TRT, so that the residual pressure preheating power generation power is fully improved, and the aims of high efficiency and energy saving are fulfilled.

The utility model aims at the characteristics of more users and relative dispersion of blast furnace gas, the gas desulfurization is relatively centralized, the investment cost is low, and the management is convenient; the problems of relative dispersion of flue gas desulfurization equipment, large industrial investment and the like can be solved.

The blast furnace gas treated by the method disclosed by the utility model is only required to be denitrated by a back-end user, so that a more economical low-temperature denitration catalyst can be adopted for denitration, and the treatment cost of tail-end waste gas is greatly reduced.

Acid gas in blast furnace gas can severely corrode a conveying pipeline; according to the research of pipeline corrosion prevention technology, CO existing in blast furnace gas₂、H₂S、Cl^-And the like, which can cause increased corrosion of the pipeline and downstream equipment. The blast furnace gas treated by the method reduces the corrosion of acid gas to a conveying pipe network, improves the safety of gas conveying and prolongs the service life of equipment.

The utility model can solve the SO of the steel mill from the source₂The problem that the emission does not reach the standard is solved, and the intention about promoting and implementing the ultralow emission of the steel industry printed by the department of ecological environment is responded activelyIn the item of 'strengthening source control, blast furnace gas and coke oven gas should be subjected to fine desulfurization'; meanwhile, blast furnace gas desulfurization is an important judgment for the selection of A-type enterprises in the classification conditions of iron and steel enterprises by the nation. In addition, the source treatment is adopted, the blast furnace gas fine desulfurization is implemented, the sulfur content in the gas can be reduced, the pressure of flue gas treatment is greatly reduced, even flue gas treatment equipment is omitted, and the pollutant control cost of downstream users is reduced.

The process flow of the utility model is as follows: after the blast furnace raw gas passes through a gravity dust removal system, a bag type dust removal system and a turbine power generation system, the waste heat and the residual pressure of the blast furnace gas are greatly utilized; the utility model is arranged at the rear end of a turbine, and blast furnace gas enters a catalytic oxidation tower after being cooled by an ammonia spraying tower, mixed with ammonia and subjected to auxiliary dechlorination; the catalytic oxidation tower is filled with a catalyst which is a carbon-based microcrystalline material and can be used for catalytically oxidizing COS into sulfur simple substances and ammonium sulfate crystals for adsorption; the blast furnace gas without organic sulfur is sent into a desulfurizing tower to remove inorganic sulfur and Cl elements; the clean coal gas after desulfurization and dechlorination is sent into a downstream blast furnace gas pipe network.

In the catalytic oxidation tower 2, COS in the blast furnace gas is reacted with NH under the action of a catalyst₃、O₂The reaction is as follows:

COS+1/2O₂→CO₂+S

COS+2O₂+H₂O+2NH₃→(NH₄)₂SO₄+CO₂

in the catalyst regeneration tower 3, the decomposition reaction of ammonium sulfate is as follows:

(NH₄)₂SO₄→NH₄HSO₄+NH₃

2NH₄HSO₄→(NH₄)₂S₂O₇+H₂O

3(NH₄)₂S₂O₇→2NH₃+2N₂+6SO₂+9H₂O

3(NH₄)₂SO₄→4NH₃+N₂+3SO₂+6H₂O

in the desulfurization tower 4, the inorganic sulfur and Cl elements in the blast furnace gas react as follows:

H₂S+NH₄OH→NH₄HS+H₂O

2NH₄OH+H₂S→(NH₄)₂S+2H₂O

SO₂+2NH₃·H₂O→(NH₄)₂SO₃+H₂O

HCl+NH₄OH→NH₄Cl+H₂O

the regeneration reaction in the regeneration tower 5 is as follows:

NH₄HS+1/2O₂→NH₄OH+S

(NH₄)₂S+1/2O₂+H₂O→2NH₄OH+S

2NH₄HS+2O₂→(NH₄)₂S₂O₃+H₂O

2(NH₄)₂S₂O₃+O₂→2(NH₄)₂SO₄+2S。

the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Claims

1. The utility model provides a blast furnace gas desulfurization dechlorination purifier, its characterized in that, the device is including spouting ammonia tower, catalytic oxidation tower, catalyst regeneration tower, desulfurizing tower, regeneration tower, hot-blast furnace, sulphur foam groove, sulphur melting kettle, process water tank, gas holder, waste water tank, ammonia storage tank, sulfur storage tank, spout ammonia tower one side and introduce blast furnace gas, the other side is connected with catalyst regeneration tower all the way, and the other way is connected with catalytic oxidation tower, catalytic oxidation tower connects gradually desulfurizing tower, regeneration tower, sulphur foam groove, catalyst regeneration tower is connected with catalytic oxidation tower, spout ammonia tower still is connected with the desulfurizing tower, process water tank one side is connected with spouting ammonia tower, the other side is connected with the desulfurizing tower, the desulfurizing tower still is connected with the gas holder, the hot-blast furnace is connected between desulfurizing tower and gas holder, waste water tank respectively with spouting ammonia tower, catalytic oxidation tower, desulfurizing tower, The regeneration tower is connected with an air compressor, the ammonia storage tank is connected between the ammonia spraying tower and the desulfurizing tower, and the sulfur storage tank is respectively connected with the catalytic oxidation tower and the catalyst regeneration tower.

2. The blast furnace gas desulfurization and dechlorination purification device according to claim 1, wherein a tower body of the ammonia spraying tower is provided with a first inlet flue, a first outlet flue, a first demister flushing water spraying layer, a first demister, a first ammonia water spraying layer, a first water sealing unit, a first emergency liquid discharge port, a first ammonia water circulating port, a first liquid collecting tank and a first waste liquid discharge port;

the first liquid collecting tank is positioned at the bottom of the tower body;

the first waste liquid outlet is arranged below the other side of the tower body and used for discharging ammonia-containing lean liquid to a waste water tank to extract ammonium salt.

3. The blast furnace gas desulfurization and dechlorination purification apparatus according to claim 1 or 2, wherein the tower body of the catalytic oxidation tower is provided with a first blast furnace gas inlet, a first blast furnace hot gas inlet, a first catalyst inlet, a second catalyst inlet, a first catalyst discharge outlet, a second catalyst discharge outlet, a first catalyst support screen, a second catalyst support screen, a first hot gas outlet and a first sulfur discharge outlet;

4. The blast furnace gas desulfurization, dechlorination and purification device of claim 3, wherein the tower body of the catalyst regeneration tower is provided with a second blast furnace gas inlet, a second blast furnace hot gas inlet, a third catalyst inlet, a fourth catalyst inlet, a third catalyst discharge outlet, a fourth catalyst discharge outlet, a third catalyst support screen, a fourth catalyst support screen, a second hot gas outlet and a second sulfur discharge outlet;

the fourth catalyst feed port and the fourth catalyst discharge port are respectively arranged at two opposite sides of the lower part of the tower body, and a fourth catalyst supporting net is arranged at the position in the tower body and used for feeding and discharging;

and the second sulfur discharge port is positioned at the bottom of the tower body, is connected with the sulfur storage tank and is used for recovering liquid sulfur.

5. The blast furnace gas desulfurization and dechlorination purification device according to claim 4, wherein a tower body of the desulfurization tower is provided with a second inlet flue, a second outlet flue, a second demister flushing water spray layer, a second demister, a second ammonia water spray layer, a second water seal unit, a second emergency liquid discharge port, a second waste liquid discharge port, a second liquid collecting tank and a waste liquid regeneration port;

the waste liquid regeneration port is arranged below the other side of the tower body and is used for sending the waste liquid into the regeneration tower.

6. The blast furnace gas desulfurization, dechlorination and purification device of claim 5, wherein the tower body of the regeneration tower is provided with a liquid inlet, a gas inlet, a liquid level regulator, a sulfur foam overflow port and a third waste liquid discharge port;

7. The blast furnace gas desulfurization and dechlorination purification device according to claim 6, wherein a blast furnace gas inlet valve, a first induced draft fan and an ammonia spraying tower gas inlet valve are sequentially arranged between the blast furnace gas and the first inlet flue of the ammonia spraying tower;

8. The blast furnace gas desulfurization, dechlorination and purification device of claim 7, wherein a gas outlet valve of the catalytic oxidation tower is arranged on the first hot gas outlet of the catalytic oxidation tower;

9. The blast furnace gas desulfurization, dechlorination and purification device of claim 8, wherein a second outlet flue of the desulfurization tower is connected with a gas outlet valve of the desulfurization tower and a sixth induced draft fan, and then one path of the flue is connected with a gas outlet of the blast furnace through the gas outlet valve of the blast furnace, and the other path of the flue is connected with the hot blast furnace through an inlet valve of the hot blast furnace;

the waste liquid regeneration port of the desulfurizing tower is connected with the liquid inlet of the regenerating tower through a regenerated waste liquid outlet valve of the desulfurizing tower, a waste liquid conveying pump and a regenerated waste liquid inlet valve of the regenerating tower;

10. The blast furnace gas desulfurization, dechlorination and purification device of claim 9, wherein the liquid level regulator of the regeneration tower is connected between the total control valve of the ammonia water spraying layer of the desulfurization tower and the ammonia supply pump of the desulfurization tower through a desulfurization circulating liquid reflux pump and an outlet valve of the liquid level regulator;

the sulfur foam groove outlet of the sulfur foam groove is connected with the sulfur melting kettle through a sulfur foam groove outlet valve, a sulfur foam pump and a sulfur melting kettle inlet valve.