WO2015103765A1

WO2015103765A1 - Method of using ammonia desulphurization technology to efficiently remove acidic gas sulfide

Info

Publication number: WO2015103765A1
Application number: PCT/CN2014/070432
Authority: WO
Inventors: 罗静; 祁丽昉; 徐长香; 罗勇迎; 傅国光; 高瑞华
Original assignee: 江苏新世纪江南环保股份有限公司
Priority date: 2014-01-10
Filing date: 2014-01-10
Publication date: 2015-07-16

Abstract

A method of using an ammonia desulphurization technology to efficiently remove acidic gas sulfide comprises the following steps: 1) preprocessing: through sulfur recovery, acid preparation and/or incineration preprocessing methods used for acidic gas, converting remaining sulfur in the acidic gas into sulfur oxides and obtaining acidic tail gas comprising the sulfur oxides, wherein the acidic gas comes from a petrochemical industry, a natural gas chemical industry, and a coal chemical industry and the like; 2) ammonia absorption of the sulfur oxides: feeding the acidic tail gas comprising the sulfur oxides into an ammonia absorption apparatus and using circulating absorption liquid to absorb the sulfur oxides; 3) ammonium sulfate post-processing: after saturated or nearly saturated absorption liquid that fully absorbs the sulfur oxides are condensed, crystallized, solid-liquid separated and dried, a solid ammonium sulfate product is obtained. The sulfur oxides (sulfur dioxide, sulfur trioxide and a hydrate thereof) in the acidic tail gas is removed, sulfuric acid, sulfur and ammonium sulfate are produced, and clean gas discharge up to standard.

Description

Method for efficiently removing acid gas sulfide by using ammonia desulfurization technology

First, the field of technology

The invention relates to an ammonia gas desulfurization method for efficiently removing acid sulfur sulfides (hydrogen sulfide, sulfur dioxide, carbonyl sulfide cos) in the production processes of petrochemical, natural gas chemical, coal chemical, shale oil chemical, shale gas chemical, sulfuric acid industry and the like. ,

CS _2, etc., the following method), specifically involves the acid gas after pretreatment, using liquid ammonia or ammonia as an absorbent to remove sulfur oxides (sulphur dioxide, sulfur trioxide and its hydrates in acidic tail gas, the same below) And by-product sulfuric acid, sulfur, ammonium sulfate, clean gas discharge standards, no three waste discharge purification methods, used in chemical, environmental protection, electricity, metallurgy, paper and other technical fields. Second, the background technology

Acid gas refers to a process gas containing sulfur compounds such as hydrogen sulfide, sulfur oxides, organic sulfur, etc., derived from petrochemical, natural gas chemical, coal chemical, shale oil chemical, shale gas chemical, sulfuric acid tail gas, etc. The main components are hydrogen sulfide, sulfur dioxide, cos, cs _2, etc., and the concentration is high, and it needs to be processed to reach the standard discharge.

There are various methods for the acid gas pretreatment technology containing sulfides, such as conventional Claus technology, dry sulfuric acid technology, FCC regeneration flue gas treatment technology, incineration technology, wet sulfuric acid technology, super Claus technology and the like.

After the above pretreatment process, the acid gas is still difficult to meet the environmental protection standards, and it cannot be directly discharged, and further treatment is needed. Further gas treatment technologies include Super Klaus, SCOT, Organic Amine, Bio-Desulfurization, Wet Sulfuric Acid, Berg Technology, Activated Carbon, and the like. As the environmental sulphur emission standards continue to increase and become stricter, it is necessary to continuously raise the sulfur recovery requirements, that is, to achieve a sulfur recovery rate of 99.9% or more, and the sulfur oxide concentration in the exhaust gas is controlled to be 100 mg/Nm ³ or even 50 mg/Nm ³ or less. .

The prior art has disclosed some methods for efficiently removing acid gas sulfides using ammonia desulfurization techniques. CN200910188118 discloses a high-concentration flue gas desulfurization method, which uses sodium desulfurization and simultaneously recovers by-product sodium sulfite, wherein desulfurization treatment is performed before flue gas desulfurization. Treated flue gas sulfur dioxide concentration in the range of 10000-100000mg / m ^3, the oxygen content in the range 2000-10000mg / m ^3, the sulfur dioxide concentration in flue gas after treatment is less than 200mg / m ^3. Compared with the common sodium sulfite method, this method of deoxidation requires conversion of part of sulfur dioxide to low-value low-concentration sulfuric acid efflux, and the recovery rate of sulfur dioxide in the flue gas is reduced. And the purity of the product is low, and the operation cost of this method is high.

CN200580011908.X discloses a biological desulfurization technology for biologically desulfurizing Claus tail gas to obtain a desulfurized tail gas and a sulfur product. The main process is as follows: The exhaust gas is introduced into the absorber, and is contacted with a poor solvent to obtain a desulfurization tail gas and a rich solvent, and the rich solvent is introduced into the bioreactor device to biooxidize the dissolved hydrogen sulfide to obtain a sulfur product and a poor solvent. The hydrogen sulfide in the exhaust gas can be less than 10 ppm. This method has a large investment, is difficult to operate, has waste liquid discharge, and is stable and stable in biological activity.

US5019361 describes the Cansolv process, sulfur dioxide concentration 7 X 10 - ⁴ -5 X 10" ³ , organic amine solution mass concentration of not less than 20%, absorption temperature of 10 ° C -50 ° C, absorption of sulfur dioxide per 1000 g of absorption liquid Greater than 100g, desorption temperature From 70 ° C to 90 ° C, 4 g to 10 g of steam is consumed per desorption of lg of sulfur dioxide. This method has a large investment, waste acid emissions and high energy consumption.

CN201010519504.6 discloses a two-stage Claus exhaust and SCOT treatment process, and the SCOT process comprises: a reduction process and an absorption process. The reduction process involves reducing all of the sulfur-containing compounds in the off-gas to hydrogen sulfide. The absorption treatment process comprises: first condensing and removing water in the process gas, and then selectively removing hydrogen sulfide from the amine, and recycling the rich amine solution, and recycling the acid gas to the Claus device. The total sulfur emissions from the tail gas after treatment are less than 300 Χ 10 - ^δ . This method has a large investment, high operating costs, and the exhaust gas indicators cannot meet the latest environmental indicators.

CN201210288895 discloses a method for treating Claus process tail gas, which continuously adds Claus process tail gas containing sulfur dioxide, oxygen and water to a reactor filled with porous carbon desulfurizer, and reacts at 30 ° C - 150 ° C At the temperature, sulfur dioxide and water in the exhaust gas undergo catalytic oxidation reaction on the surface of the porous carbon to form sulfuric acid, and the regenerated detergent is continuously introduced into the reactor. The desulfurization rate of this method is up to 93%, and the final exhaust gas emission cannot meet the high environmental protection requirements, and the by-product low-concentration sulfuric acid is difficult to use. Multi-stage Claus process tail gas still cannot meet the emission requirements. In short, when the acid gas from Claus's reduction of desulfurization comes from coal-based chemical industry and coking, the acid gas is pretreated to Claus treatment because of the high sulfur content of coal.

The method for efficiently removing acid gas sulfide by ammonia desulfurization technology includes the patented ammonia desulfurization series patents, such as CN200510040801.1, CN03158258.3 CN201010275966.8, CN200510040800.7, CN03158257.5, and the like. These methods are to solve the problem of desulfurization of large coal-fired power plants. According to the content of sulfur dioxide in the original tail gas, the sulfur dioxide content of the original tail gas is adjusted to a suitable absorption condition by supplementing the air; The applicant 2013101302254 acid tail gas ammonia method is also required to adjust the sulfur dioxide concentration of the absorber tail gas by adding air: 30000mg/ Nm ³ is processed again.

Third, the invention content

The object of the present invention is to provide an ammonia gas desulfurization method for efficiently removing acid sulfur sulfides (hydrogen sulfide, sulfur dioxide, etc.) in the production processes of petrochemical, natural gas chemical, coal chemical, shale oil chemical, shale gas chemical, sulfuric acid industry and the like. The method of carbonyl sulfide COS, cs _2, etc., the same as the above), the acid gas purification is complete, ensuring that the clean gas reaches the standard discharge, can meet the strict environmental emission requirements of the world, and realize the efficient purification of acid gas. The process is simple, the operation is simple, the device runs stably, and some shortcomings of the existing process are avoided.

The technical solution of the present invention is: A method for efficiently removing acid gas sulfide by using an ammonia desulfurization technology, which is characterized by comprising the following steps:

1) Pretreatment: The sulfide in the acid gas is converted into sulfur oxides by a pretreatment method such as sulfur recovery, acid production or/incineration to obtain an acid tail gas containing sulfur oxides; The acid gas is derived from industrial tail gas such as petrochemical, natural gas chemical, coal chemical, shale oil chemical, shale gas chemical, sulfuric acid industry; 2) Sulfur oxide ammonia absorption: The acid tail gas of the sulfur oxide is introduced into the ammonia absorption device, and the sulfur oxide is absorbed by the circulating absorption liquid, and the absorption parameter is determined according to the sulfur oxide removal amount and the sulfur oxide concentration. Adjusted, treated clean air up to standard discharge;

3) Post-treatment of ammonium sulfate: a saturated or nearly saturated absorption liquid which sufficiently absorbs sulfur oxides is concentrated, crystallized, solid-liquid separated, dried, and packaged to obtain a solid ammonium sulfate product;

Further, the concentration of sulfur oxides in the acid tail gas (calculated as the concentration of sulfur dioxide, the same applies hereinafter) is 500 to 30000 mg/Nm ³ , thereby reducing the investment and operating cost of the pretreatment apparatus and improving the operational stability. When the concentration of sulfur oxides in the acid tail gas is 500-30000mg/Nm ³ , the concentration of sulfur oxides in clean gas is less than 50mg/Nm ³ , the free ammonia is less than 10mg/Nm ³ , the recovery rate of ammonia is more than 97%, and the desulfurization efficiency of ammonia desulfurization unit is 99.9. %the above.

Further, according to the difference of the sulfur oxide concentration and the sulfur oxide absorption amount in the acidic tail gas, the parameters such as the composition, density, and circulation amount of the absorption liquid are adjusted; and the desulfurization efficiency is ensured to be 99.9% or more, and the investment and operation cost are saved.

Further, acid gas pretreatment is an existing mature technology or patented technology, such as conventional Claus technology, dry sulfuric acid, incineration technology, FCC regeneration flue gas technology, wet sulfuric acid technology, super Claus technology, or super good Rolls technology; acid gas is sulfur recovery tail gas, sulfuric acid tail gas, incineration flue gas, FCC regeneration flue gas, etc.;

Further, when the concentration of sulfur oxides in the acid gas is lower than ^30,000 mg/Nm ³ , the direct deamination absorption device is not provided with pretreatment.

Acid gas, especially from coal-to-methanol, acetic acid projects, coal-to-natural gas (coking) projects, shale gas or oil extraction and utilization projects or natural gas extraction projects, after pretreatment, acid tail gas is re-extracted in the ammonia desulfurization range. Ammonia desulfurization, desulfurizer is 5%-35% ammonia or liquid ammonia. Berg, Biodesulfurization, Cansolv.

In particular, the acid gas is derived from a coal gas (or coke) unit, and the acid gas pretreatment is one of the first to third grades of Claus treatment.

The treatment method proposed by the invention has the sulfur oxide removal efficiency ≥99.9%, the by-product is ammonium sulfate, and the clean gas reaches the standard discharge, and the investment is low, the process flow is simple, and the operation cost is low.

The process and apparatus for the absorption of the sulfur oxide ammonia method of the present invention do not involve the use of the prior art or the patented series of ammonia desulfurization devices authorized by our company. Such as CN200510040801.1 CN03158258.3, CN201010275966.8 CN200510040800.7, CN03158257.5 and the like.

Advantageous Effects of the Invention: The present invention relates to an ammonia gas desulfurization technology for efficiently removing acid sulfur sulfides (vulcanization) in the production processes of petrochemical, natural gas chemical, coal chemical, shale oil chemical, shale gas chemical, sulfuric acid industry, and the like. Hydrogen, sulfur dioxide, cos, cs _2, etc., the same method below, specifically involving acid gas after pretreatment, using liquid ammonia or ammonia as absorption To remove sulfur oxides (sulphur dioxide, sulfur trioxide and its hydrates from the acidic tail gas, the same below) and produce sulfuric acid, sulfur, ammonium sulfate, clean gas up to standard discharge, no three wastes purification method, used in chemical industry, Environmental protection, power, metallurgy, paper and other technical fields. The method of using ammonia desulfurization technology to remove acid sulfur sulfide efficiently has high total sulfur recovery rate, low investment, low operating cost, no three-waste discharge, no secondary pollution, and complete resource utilization.

The invention is adaptable to various acid gases. Especially when the acid gas comes from the coal gas (or coke) device, because the sulfur in the coal is not treated, the manager pre-treatment and then ammonia desulfurization, including shale gas or oil exploitation and utilization projects or natural gas exploitation projects, After pretreatment, the acid tail gas is further desulfurized by ammonia desulfurization in the range of ammonia desulfurization, and the cost is reduced. The pretreatment can be a conventional method, and the desulfurization of the desulfurization by the ammonia method is ensured, especially It is a method with a high input-output ratio. The concentration of sulfur oxides in clean air is guaranteed to be below 50mg/Nm ³ , which can meet increasingly stringent environmental requirements. The by-product ammonium sulfate of the invention can be directly sold out, has no secondary pollution, has low investment, low running cost and simple operation.

The ammonia desulfurization device of the invention has a investment of 30-50% lower than that of the super-Klaus, SCOT, organic amine, activated carbon, Berg, biological desulfurization, Cansolv, and wet sulfuric acid.

The operating cost of the ammonia desulfurization unit is 20-40% lower than that of the superior Klaus, SCOT, organic amine, activated carbon, Berg, biological desulfurization, Om _S0 l _V , and wet sulfuric acid.

The invention is also characterized in that the total sulfur recovery rate (ammonia desulfurization) of 99.9% or more is achieved with a lower investment and operating cost, that is, the desulfurization efficiency of the device is not less than 99.9%, and there is no secondary pollution. And to ensure that the clean gas reaches the standard discharge, it can meet the requirements of high environmental standards and achieve efficient purification of acid gas. The process flow is simple, the operation is simple, and the device operation is stable. The pretreatment technology corresponding to the present invention may be a mature technology disclosed in the industry, or may be a newly developed patent application technology. Due to the high desulfurization efficiency of the ammonia desulfurization unit, the sulfur recovery rate of the pretreatment unit can be reduced, thereby reducing the investment and operating cost of the pretreatment.

The acid gas purification method adopted by the invention ensures that the clean gas reaches the standard discharge, can meet the strict environmental protection discharge requirements in the world, and realize the high-efficiency purification of the acid gas. The process is simple, the operation is simple, the device is stable, and some shortcomings of the existing process are avoided, forming a unique advantage. The method of the invention is also superior to the desulfurization methods such as "pretreatment + SCOT", "pretreatment + biological desulfurization".

Fourth, the description of the drawings

Figure 1 is a flow chart of a method for efficiently removing acid gas sulfide by ammonia desulfurization technology.

Figure 2 is a block diagram of the acid gas treatment plant of the coal chemical project.

Figure 3 is a block diagram of the acid gas treatment plant of the coal-to-gas project.

Figure 4 is a block diagram of the acid gas treatment unit of the shale oil mining and utilization project. Figure 5 is a block diagram of the acid gas treatment unit of the shale gas mining and utilization project.

Figure 6 is a block diagram of the acid gas treatment plant of the coal-to-liquids project.

Figure 7 is a block diagram of the acid gas treatment unit of the natural gas production project.

Figure 8 is a block diagram of the acid gas treatment plant of the chemical project.

Figure 9 is a block diagram of the acid gas processing unit of the papermaking project.

Figure 10 is a block diagram of the acid gas treatment unit of the refinery project.

V. Specific implementation methods

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

The specific process steps of the present invention are as follows:

1, pretreatment

After pretreatment of acid gas, the concentration of sulfur oxides is 500 mg/Nm ³ -30000 mg/Nm ³ ; acid gas comes from coal to methanol, acetic acid project, coal-to-gas project, shale gas or oil exploitation and utilization project or natural gas. In the mining project, when the concentration of sulfur oxides of the acid tail gas after the first-stage Claus process is more than ^30,000 mg/Nm ³ , after the second to third grade Claus process, the acid tail gas is desulfurized within the ammonia desulfurization range. Ammonia desulfurization is carried out. The aforementioned Claus process may include conventional Claus technology, Super Claus technology. However, in comparison with the input and output of new projects, the invention in particular pre-treatments in particular employs conventional first- to third-level Claus technology. Conventional Claus technology is already a publicly disclosed technology in the industry, and the cost is controllable and will not be described in detail.

2, sulfur oxide ammonia absorption

1) Absorb sulfur oxides with absorption liquid, and add liquid ammonia or ammonia water to the absorption liquid. Under suitable operating conditions, the sulfur oxides in the acid tail gas are removed in the absorption tower, and the removal rate is 99.9% or more. The absorption tower adjusts the composition and circulation amount of the absorption liquid according to the amount and concentration of sulfur oxides in the acid tail gas, and the absorption liquid for removing the sulfur oxide is oxidized, concentrated, crystallized, and then treated with ammonium sulfate. system. Typical examples are as follows:

1-1) Sulfur dioxide concentration in the tail gas of the absorption tower: 30000mg/Nm ³ ;

1-2) The process water is set in the inlet flue or absorption tower of the absorption tower or sprayed with ammonium sulfate solution to cool down, and the original tail gas is cooled and washed; when the ammonium sulfate solution is used for spraying and cooling, the concentration of ammonium sulfate itself is improved;

1-3) an oxidation section is arranged in the absorption tower, and an oxidation distributor is arranged in the oxidation section to realize oxidation of the desulfurization absorption liquid;

1-4) an absorption section is arranged in the absorption tower, and the absorption section is absorbed by the ammonia-containing absorption liquid in the absorption section to absorb the desulfurization spray; the ammonia-containing absorption liquid is filled in the ammonia storage tank;

1-5) a water washing layer is arranged on the upper part of the absorption section in the absorption tower, and the water washing layer washes the absorption liquid in the exhaust gas to reduce the escape of the absorption liquid;

1-6) a mist eliminator is arranged in the upper part of the water washing layer in the absorption tower to control the content of the mist in the exhaust gas; the acid tail gas ammonia method smoke The gas treatment process is as follows: Acid tail gas adjusts the concentration of sulfur dioxide in the flue gas through the air sent by the blower in the original flue gas flue, and cools the spray layer at the inlet of the absorption tower or the cooling spray sprayed with the ammonium sulfate solution in the absorption tower. After the washing effect of the layer is lowered, the temperature enters the absorption tower, and after the absorption tower absorbs the spray layer in the absorption tower, the sulfur dioxide is removed, and then washed and absorbed by the water washing layer, and the mist in the flue gas is removed by the mist eliminator to remove the mist. The purified exhaust gas is discharged to the chimney through the net flue gas flue.

The absorption liquid circulation is a first-stage circulation or a two-stage circulation; the secondary circulation system is a concentrated crystallization cycle of cooling spray, and the ammonium sulfate solution is pumped from the ammonium sulfate storage tank into the absorption tower by the cooling washing pump to cool the washing spray layer. And / or the absorption tower cooling cooling layer, the flue gas is cooled, and it is evaporated to concentrate or even crystallize.

Into the absorption tower to absorb the original flue gas temperature of the spray layer: 80 ° C; absorption tower absorption spray layer operating temperature: 65 ° C; absorption liquid temperature: 65 ° C.

Absorption tower empty tower gas velocity: 1.5 m / s -4 m / s; cooling washing liquid to gas ratio: 6 L / m ³ ; absorption spray liquid to gas ratio: 1 L / m ³ -15 L / m ³ ; product ammonium sulfate The solution concentration was 15%.

A post-ammonia tail gas treatment process for Claus sulfur recovery or improved Claus sulfur recovery; use of additional air for cooling, cooling with process water or with ammonium sulfate solution.

2) Other operations of the absorption tower

In order to cooperate with the whole process, the absorption tower needs other auxiliary operations, such as absorption liquid oxidation, absorption liquid concentration, and aerosol control.

3. Post-treatment of ammonium sulfate

After the ammonium sulfate solution is concentrated and crystallized, the ammonium sulfate post-treatment system is used. According to actual needs, the by-product absorbed by the ammonia method may be solid ammonium sulfate or ammonium sulfate solution.

4. When the acid sulfur concentration is less than 30,000 mg/Nm ³ , it can be directly desulfurized by ammonia removal without pretreatment.

Applications:

1. Acid gas treatment device for a coal chemical project

The acid gas is from a coal-based methanol and acetic acid project. The acid tail gas (Klaus tail gas) treated by the two-stage Claus process has a total amount of 9500 Nm ³ /h, a temperature of 195 ° C, and a S0 ₂ concentration of 23,000 mg/Nm ³ - 29700mg/Nm ³ , the rest are nitrogen, carbon dioxide, water vapor, oxygen and so on. The pressure is 0.023 MPa (g). The desulfurizing agent was 99.6% liquid ammonia.

The block diagram of the device is shown in Figure 2. The acid gas contains 30%~45% (V) hydrogen sulfide. The sulfur element in the pretreatment process is completely converted into sulfur and S0 ₂ . The concentration of 80 ₂ in the acid tail gas after pretreatment satisfies the requirement of sulfur oxide ammonia absorption. The method for efficiently removing acid sulfur sulfide by using ammonia desulfurization technology according to the invention has the advantages of simplified process, simple control, reduced equipment investment and operating cost, and clean gas compliance discharge compared with the super-extra Claus process. At the same time, by-product ammonium sulfate.

The ammonia recovery rate of this example is more than 98.0%, and the average sulfur oxide concentration in clean gas is 25.7mg/Nm ³ , free ammonia. 4.5mg/Nm ³ , the desulfurization efficiency is 99.91%.

The S0 ₂ concentration of the acid exhaust gas and the export clean gas imported from the sulfur oxide ammonia absorption device is as follows:

2. Acid gas treatment device for a coal-to-gas project

The acid gas is from a coal-to-gas project. The acid tail gas (Klaus tail gas) after two-stage Claus is 32000Nm ³ /h, the temperature is 195°C, and the S0 ₂ concentration is 21000 mg/Nm ³ ~29800mg/Nm ³ The rest are nitrogen, carbon dioxide, water vapor, oxygen, etc. The pressure is 0.023 MPa (g). The desulfurizing agent is 11% to 21% ammonia water.

The block diagram of the device is shown in Figure 3. The acid gas contains 30%~40% (V) hydrogen sulfide. The sulfur element in the pretreatment process is completely converted into sulfur and S0 ₂ . The concentration of S0 ₂ in the acid tail gas after pretreatment satisfies the requirement of ammonia oxide absorption of the sulfur oxide. The method for efficiently removing acid gas sulfide by utilizing ammonia desulfurization technology according to the present invention has the advantages of simplified process, simple control, reduced equipment investment and operation cost, clean gas compliance discharge, and vice versa. Production of ammonium sulfate.

The ammonia recovery rate of the example is 98.5% or more, the average sulfur oxide concentration in the clean gas is 23.6 mg/Nm ³ , the free ammonia is 6.3 mg/Nm ³ , and the desulfurization efficiency is 99.9%.

Acid tail gas so ₂ concentration clean gas S0 ₂ concentration desulfurization efficiency (%)

Mg/Nm ³ mg Nm ³ 21253 19.5 99.91

23729 23.7 99.90

25347 25.5 99.90

28571 26.8 99.91

29870 22.7 99.92

The process comparison is as follows:

3. Acid gas treatment device for a shale oil exploitation and utilization project

The acid gas comes from a shale oil exploitation and utilization project. After the third-grade Claus exhaust acid exhaust (Klaus tail gas), the total amount is 12500Nm ³ /h, the temperature is 195°C, and the S0 ₂ concentration is 23000 mg/Nm ³ -27000mg/ Nm ³ , the rest are nitrogen, carbon dioxide, water vapor. The pressure is 0.023 MPa (g). The desulfurizing agent was 99.6% liquid ammonia.

The block diagram of the device is shown in Figure 4. The acid gas contains 50%~80% (V) hydrogen sulfide. The sulfur element in the pretreatment process is completely converted into sulfur and S0 ₂ . The concentration of 80 ₂ in the acid tail gas after pretreatment satisfies the requirement of sulfur oxide ammonia absorption. The method for efficiently removing acid sulfur sulfide by using ammonia desulfurization technology according to the invention has the advantages of simplified process, simple control, reduced equipment investment and operation cost, clean gas compliance discharge, and vice versa. Production of ammonium sulfate.

The ammonia recovery rate of this example is 98.5% or more, the average S0 ₂ concentration in the clean gas is 19.4 mg/Nm ³ , the free ammonia is 5.1 mg/Nm ³ , and the desulfurization efficiency is 99.92%.

Mg/Nm ³ mg Nm ³

23056 19.0 99.92

24308 22.0 99.91

25714 20.3 99.92 26503 17.6 99.93

27121 18.2 99.93

The process comparison is as follows:

4. Acid gas treatment device for a shale gas mining and utilization project

The acid gas comes from a shale gas mining and utilization project. After two grades of Claus acid exhaust (Klaus tail gas), the total amount is 15000Nm ³ /h, the temperature is 175 °C, and the S0 ₂ concentration is 14000 mg/Nm ³ -19500mg/ Nm ³ , the rest are nitrogen, carbon dioxide, water vapor, oxygen, etc. The pressure is 0.03 MPa (g). The desulfurizing agent is 10%-20% ammonia water.

The block diagram of the device is shown in Figure 5. The acid gas contains 25%~45% (V) hydrogen sulfide. After pretreatment, the sulfur element is completely converted into sulfur and S0 ₂ . The concentration of S0 ₂ in the acid tail gas after pretreatment satisfies the requirement of sulfur oxide ammonia absorption. The method for efficiently removing acid sulfur sulfide by using ammonia desulfurization technology described in this patent is simpler than the low temperature SCOT process, and the control is simple, the device investment and operation cost are reduced, and the clean gas reaches the standard discharge. Production of ammonium sulfate.

The ammonia recovery rate of this example is more than 98.0%, the average S0 ₂ concentration in clean gas is 16.3 mg/Nm ³ , the free ammonia is 4.8 mg/Nm ³ , and the desulfurization efficiency is 99.90%.

The S0 ₂ concentration of the acid exhaust gas and the outlet clean gas imported from the sulfur oxide absorber is as follows:

The process comparison is as follows:

Process route ammonia desulfurization low temperature SCOT

Investment / 10,000 yuan 3600 Operating cost / million 460 1600

Average desulfurization efficiency /% 99.90 97.1

Clean gas average so ₂ concentration /

16.3 480

Mg/Nm ³

5. Acid gas treatment device for a coal-to-liquid project

The acid gas comes from a coal-to-liquids project. After two grades of Claus, the acid tail gas (Klaus tail gas) is 48000Nm ³ /h, the temperature is 195 °C, and the S0 ₂ concentration is 25000 mg/Nm ³ -29500mg/Nm ³ . The rest are nitrogen, carbon dioxide, and water vapor. The pressure is 0.023 MPa (g). The desulfurizing agent is 8%-32% ammonia water.

The block diagram of the device is shown in Figure 6. The acid gas contains 40%~60% (V) hydrogen sulfide. After pretreatment, the sulfur element is completely converted into sulfur and S0 ₂ . The concentration of S0 ₂ in the acid tail gas after pretreatment satisfies the requirements of sulfur oxide ammonia absorption. The method for efficiently removing acid sulphide by ammonia desulfurization technology described in this patent is simpler than the Cansolv process, and the control is simple, the device investment and operation cost are reduced, the clean gas reaches the standard discharge, and the by-product is produced at the same time. Ammonium sulfate.

The ammonia recovery rate of this example is above 99.0%, the average S0 ₂ concentration in clean gas is 25.5 mg/Nm ³ , the free ammonia is 5.5 mg/Nm ³ , and the desulfurization efficiency is 99.91%.

The process comparison is as follows:

6. Acid gas treatment device for a natural gas mining project The acid gas comes from a natural gas exploitation project. After a first-degree Claus acid exhaust (Klaus tail gas), the total amount is 36000 Nm ³ /h, the temperature is 155 ° C, and the S0 ₂ concentration is 22500 mg/Nm ³ -26500 mg/Nm ³ . It is nitrogen, carbon dioxide, and water vapor. The pressure is 0.03 MPa (g). The desulfurizer is 5%-35% ammonia.

The block diagram of the device is shown in Figure 7. The acid gas contains 15%~30% (V) hydrogen sulfide. After pretreatment, the sulfur element is completely converted into sulfur and S0 ₂ . The concentration of S0 ₂ in the acid tail gas after pretreatment satisfies the requirement of sulfur oxide ammonia absorption. The method for efficiently removing acid sulfur sulfide by using ammonia desulfurization technology described in the patent has the advantages of simplified process, simple control, reduced equipment investment and operating cost, and clean gas compliance as compared with the wet sulfuric acid + alkali absorption process. Emission, while by-product ammonium sulfate.

The ammonia recovery rate of the example is above 99.0%, the average sulfur oxide concentration in the clean gas is 19.4 mg/Nm ³ , the free ammonia is 4.2 mg/Nm ³ , and the desulfurization efficiency is 99.92%.

The process comparison is as follows:

Acid gas treatment device for a chemical project

The acid gas is from a chemical project. After the pretreatment of dry sulfuric acid secondary conversion, the total acid tail gas is 128000 Nm ³ /h, the temperature is 145 ° C, the sulfur oxide concentration is 18500 mg/Nm ³ -23000 mg/Nm ³ , and the rest is nitrogen. Carbon dioxide, oxygen, etc. The pressure is 0.023 MPa (g). The desulfurizing agent was 99.6% liquid ammonia.

The block diagram of the device is shown in Figure 8. The acid gas contains 75%~90% (V) hydrogen sulfide, and the sulfur element is completely processed by the pretreatment process. Conversion to sulfuric acid, so ₂ , the concentration of sulfur oxides in the acidic tail gas after pretreatment meets the requirements of the absorption of sulfur oxides by ammonia, and the method for efficiently removing acid sulfur sulfide by using ammonia desulfurization technology according to the present invention, Compared with the catalyst upgrade + alkaline washing, the process is simplified, the equipment investment and operating costs are reduced, the clean gas reaches the standard discharge, and the ammonium sulfate is produced by-product.

The ammonia recovery rate of the example is 98.5% or more, the average sulfur oxide concentration in the clean gas is 17.4 mg/Nm ³ , the free ammonia is 3.5 mg/Nm ³ , and the desulfurization efficiency is 99.92%.

The sulfur oxide concentration of the sulfur dioxide absorption device imported from the acidic tail gas and the outlet clean gas is as follows:

The process comparison is as follows:

8. Acidification treatment device for a papermaking project

The acid gas is from a papermaking project. After the first conversion of wet sulfuric acid, the total acid tail gas is 330000Nm ³ /h, the temperature is 155 °C, the sulfur oxide concentration is 25000 mg/Nm ³ -29000mg/Nm ³ , and the rest is nitrogen and carbon dioxide. Water vapor, oxygen, etc. The pressure is 0.03 MPa (g). The desulfurizing agent was 99.6% liquid ammonia.

The block diagram of the device is shown in Figure 9. The acid gas contains 35%~45% (V) hydrogen sulfide. The sulfur element in the pretreatment process is completely converted into sulfuric acid and S0 ₂ . The concentration of S0 ₂ in the acid tail gas after pretreatment satisfies the requirement of sulfur oxide ammonia absorption. The method for efficiently removing acid sulfur sulfide by using ammonia desulfurization technology described in the patent, and adding 1 grade conversion + exhaust gas activated carbon Compared with the oxidation process (ie, the wet sulfuric acid secondary conversion + exhaust gas activated carbon catalytic oxidation process), the process is simplified, the control is simple, the device investment and operation cost are reduced, no three wastes are discharged, and ammonium sulfate is produced by-product.

In this example, the ammonia recovery rate is over 98%, the average sulfur oxide concentration in the clean gas is 23.4 mg/Nm ³ , the free ammonia is 2.4 mg/Nm ³ , and the desulfurization efficiency is 99.91%.

The process comparison is as follows:

9. Acidification treatment unit for a refinery project

The acid gas is the FCC regenerative flue gas. It is from a refinery project. After the catalyst is incinerated and regenerated, the total amount of acid tail gas is 70000Nm ³ /h, the temperature is 180°C, the S0 ₂ concentration is 2900 mg/Nm ³ -4200mg/Nm ³ , and the rest is nitrogen. Carbon dioxide, water vapor, oxygen, etc. The pressure is 0.002 MPa (g). The desulfurizing agent is 10-30% ammonia water.

The block diagram of the device is shown in Figure 10. After the catalyst is incinerated and regenerated, the sulfur element is completely converted into S0 ₂ , and the concentration of S0 ₂ in the acidic tail gas after pretreatment satisfies the requirement of the absorption of sulfur oxide ammonia method, and the method of using the ammonia desulfurization technology to remove the acid gas vulcanization efficiently is adopted. The method of the material", compared with the Berger technology, the process is simplified, the equipment investment and operating costs are reduced, the clean gas reaches the standard discharge, and the ammonium sulfate is produced by-product.

The ammonia recovery rate of the example is 98.5% or more, and the average S0 ₂ concentration in the clean gas is 3. lmg/Nm ³ , and the free ammonia is 1.9 mg/Nm ³ . The desulfurization efficiency is 99.91%.

The S0 ₂ concentration table of the acid exhaust gas and the export clean gas imported from the sulfur oxide absorber is as follows:

The process comparison is as follows:

In summary, the present invention is a method for efficiently removing acid gas sulfides by an ammonia desulfurization technique. The parts not covered by the present invention are the same as the prior art or can be implemented by the prior art.

The above description is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present invention. It should be considered as the scope of protection of the present invention.

Claims

Claim

1. A method for backfilling a goaf under an underground vermiculite, characterized by comprising the steps of:

a. The vermiculite accumulated in the waste rock mountain is sequentially sent to the vertical roller crusher (4) through the vermiculite silo (1), the screw conveyor 1 (2) and the uphole belt conveyor (3), and the vermiculite is broken into a particle size of 50 mm. The following vermiculite fragments; b. The vermiculite fragments having a particle size of 50 mm or less obtained in the step a are sequentially sent to the underground through the screw conveyor 2 (5) and the vertical solid material dispenser (6).

c. The meteorite fragments with a particle size of 50mm or less that are sent into the underground are sent to the downhole roller crusher (8) through the downhole belt conveyor (7), and the vermiculite fragments with a particle size of 50mm or less are broken again into a particle size of 30mm or less. Meteorite fragments;

d. The vermiculite fragments with a particle size of 30 mm or less obtained in step c are sent to the gob area through the pneumatic conveying device (9).

2. An apparatus for backfilling downhole goaf in an uphole meteorite, characterized by: including an uphole vermiculite silo (1), an uphole pair roll crusher (4), a vertical solid material dispenser (6), a downhole roll The crusher (8) and the pneumatic conveying device (9), the discharge port of the uphole vermiculite silo (1) is sequentially connected to the uphole roller crusher through the screw conveyor 1 (2) and the uphole belt conveyor (3). (4) Feeding port, the discharge port of the uphole roller crusher (4) is connected to the inlet of the vertical solid material dispenser (6) through the screw conveyor 2 (5), vertical solid material dispenser

The discharge port of (6) is connected to the feed port of the roller crusher (8) through the downhole belt conveyor (7), and the pneumatic conveying device (9) is connected to the discharge port of the roller crusher (8).

3. The apparatus for backfilling a gob of an uphole vermiculite according to claim 2, wherein: the vertical solid material dispenser (6) comprises a horizontal feeding chamber (65) and a vertical feeding chamber (67). ) and bevel gearbox

(66), one end of the horizontal feeding chamber (65) is provided with a feeding hopper (64), and the other end of the horizontal feeding chamber (65) is connected with the upper end of the vertical feeding chamber (67), and the vertical feeding chamber (67) The lower end is provided with a discharge port (68), and a horizontal feeding screw and a vertical feeding screw are respectively arranged in the horizontal feeding chamber (65) and the vertical feeding chamber (67), and one end of the horizontal feeding screw passes through the coupling (62) Connect the reducer (61), the reducer (61) is connected to the motor, and the other end of the horizontal feed screw is connected to the vertical feed screw through the gearbox (66).

4. The apparatus for backfilling a gob of an uphole vermiculite according to claim 2, wherein: the pneumatic conveying device (9) comprises a blower (91), and the blower (91) passes through a supercharger ( 92) Connecting the delivery tube

At one end of (94), the other end of the feed pipe (94) is provided with a mine wet sprayer (95), and a feed hopper (93) is provided on the feed pipe (94).

The apparatus for backfilling a goaf under the well by the uphole vermiculite according to any one of claims 2 to 4, characterized in that: the discharge granularity of the uphole pair of roller crusher (4) is 50 mm or less; The discharge size of the downhole to the roller crusher (8) is 30 or less.