Preparation method and application method of a mercury removal agent

Abstract

The present application relates to a kind of preparation method of desulfurization waste for mercury removal agent and the method for mercury removal of mercury removal agent, the flocculent solid precipitate obtained by using fresh copper sulfate solution and circulating copper sulfate solution jointly to the blast furnace gas with relatively low concentration hydrogen sulfide content is treated as main raw material, by grinding, dry mixing, wet mixing, shaping and drying etc., the mercury removal agent obtained, outlet mercury concentration is low, mercury removal rate is high, more important is that desulfurization waste is used as raw material, environmental friendliness is greatly improved. By setting the parameters during the process of the mercury removal agent mercury removal, the mercury removal rate is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of environmental protection, in particular to the field of reusing desulfurization waste, and specifically to a preparation method and application method of a mercury removal agent. BACKGROUND

[0002] Mercury exists in natural gas, oilfield associated gas, condensate oil, gasoline, naphtha and other petrochemical products, which seriously affects the service life of catalysts in subsequent operation units of refining and petrochemical processes, and thus it is necessary to remove mercury with high precision. Mercury also exists in coke oven gas, coking gas, refinery gas and other industrial gases. In addition, a large amount of mercury-containing tail gas is generated in the process of waste incineration, which enters the atmosphere with the exhaust gas and causes environmental pollution, posing a threat to human health. The "Comprehensive Emission Standard of Air Pollutants" requires that the maximum allowable emission concentration of mercury and its compounds from existing pollution sources is 12 μg / g. A large number of researchers have devoted themselves to the development of mercury removal technology, striving to obtain a purifying agent capable of removing mercury from industrial tail gas. For example, soluble copper salt, ethylenediamine solution, ammonia and thiourea are used as raw materials to produce a mercury removal agent with copper sulfide as an active component in the prior art. However, ammonia volatilizes during heating in the production process, and thiourea decomposes into hydrogen sulfide and ammonia water, which has an unbearable odor and poses a health hazard to workers. In addition, the production yield of copper sulfide is low, and there is a by-product of cuprous sulfide.

[0003] Chinese patent publication CN101500690A uses a metal compound of copper to obtain copper sulfide, which is then used to prepare a mercury removal agent. This method uses a sulfurizing agent, resulting in high sulfurization cost and high toxicity, which affects normal production. In addition, improper treatment of the sulfurizing agent can cause it to remain in the mercury removal agent, blocking the pores of the mercury removal agent product. The sulfurizing agent can also diffuse outward during subsequent mercury removal, increasing the amount of sulfide in the raw material gas and causing problems in the subsequent removal of sulfides.

[0004] Blast furnace gas is one of the main fuels of a steel company, and its main components are CO, CO2 and N2, and it also contains a small amount of O2, COS, H2S, dust and the like. The current process route for the fine desulfurization of blast furnace gas is as follows: first, organic sulfur COS is hydrolyzed to H2S by hydrolysis, and then the sulfur-containing hydrogen sulfide gas after hydrolysis is removed by dry desulfurizer, alkali desulfurization or wet oxidation method. The dry desulfurizer method has the disadvantages of frequent replacement of the agent and difficulty in disposal of the waste agent. Alkali desulfurization and wet oxidation method require a pH greater than 9 to remove hydrogen sulfide. Since the concentration of hydrogen sulfide in the raw material gas is less than 200 mg / m 3The content of CO2 is about 20%, so the selectivity of removing hydrogen sulfide by alkali desulfurization or wet oxidation method is poor, most of the alkali solution reacts with CO2, it is difficult to maintain alkaline conditions, resulting in large alkali consumption, and a large amount of difficult-to-treat desulfurization wastewater is also produced. After the hydrolysis of the hydrolysis agent, the organic sulfur in the blast furnace gas is completely converted into inorganic sulfur hydrogen sulfide. The blast furnace gas after hydrolysis is subjected to fine desulfurization by using a blast furnace gas fine desulfurization technology capable of selectively reacting with hydrogen sulfide, and using copper sulfate solution as a desulfurization liquid. The blast furnace gas containing hydrogen sulfide is sprayed into a desulfurization spray tower, and the copper sulfate desulfurization liquid and hydrogen sulfide in the spray tower undergo a double decomposition reaction to generate precipitate copper sulfide. The desulfurization liquid does not react with CO2, and a large amount of desulfurization cost is saved. SUMMARY

[0005] The present application aims at the above technical problems, and provides a method for preparing a mercury removal agent from flocculent copper sulfide, a product of blast furnace gas fine desulfurization, and a method for removing mercury by using the mercury removal agent.

[0006] The technical scheme is specifically as follows:

[0007] A method for preparing a mercury removal agent from desulfurization waste, comprising the following steps:

[0008] (1) Fresh copper sulfate solution with a concentration of 0.1-0.5 mol / L and recycled copper sulfate solution with a concentration of 0.008-0.05 mol / L are layered and jointly sprayed into a desulfurization tower device to perform reverse contact with blast furnace gas with a hydrogen sulfide concentration of 40-150 mg / m 3 for fine desulfurization treatment of the blast furnace gas. The desulfurization liquid discharged from the bottom of the desulfurization tower device is filtered to obtain flocculent solid precipitate and recycled stock solution. The supernatant of the recycled stock solution is discharged into a circulating water pool to configure the recycled copper sulfate solution. Fresh copper sulfate solution is added to the circulating water pool to maintain the concentration of the recycled copper sulfate solution discharged from the circulating water pool into the desulfurization tower device at 0.008-0.05 mol / L.

[0009] (2) The flocculent solid precipitate obtained in step (1) is placed into a grinder to obtain copper sulfide material with a particle size of 160-320 mesh and a specific surface area of 30-38 m 2 / g. The purity of copper sulfide in the copper sulfide material is 97-99 wt%, and the content of cuprous sulfide is less than 0.5 wt%.

[0010] (3) 60-80 parts by weight of a skeleton material, 10-20 parts by weight of a binder, and 10-20 parts by weight of the copper sulfide material obtained in step (2) are jointly added to a dry mixing device, and dry mixing is performed for 10-15 minutes to obtain a dry mixed material.

[0011] (4) The dry mixture obtained in step (3) is continuously mixed under the condition of continuously spraying water, and the wet mixing time is 15-20 minutes, and the sprayed water is 20-30 parts by weight.

[0012] (5) The material after wet mixing in step (4) is extruded or rolled into a ball.

[0013] (6) The material after molding in step (5) is dried at a temperature of 100-150°C, so that the water content of the material is less than or equal to 3wt%, to obtain a mercury removal agent product.

[0014] Preferably, in step (1), the fresh copper sulfate solution is sprayed in the upper layer, and the circulating copper sulfate solution is sprayed in the lower layer.

[0015] Preferably, the skeleton material is one or both of a broken powder of an organic sulfur hydrolysis agent waste agent and a broken powder of an activated carbon desulfurization waste agent; and the binder is one or more of kaolin, portland cement, carboxymethyl cellulose, and aluminum sol.

[0016] Preferably, the organic sulfur hydrolysis agent waste agent is an organic sulfur hydrolysis agent obtained by calcining 55-90 parts by weight of activated alumina and 20-50 parts by weight of a salt of an alkali metal or an alkali of an alkali metal, and the waste agent is obtained after the organic sulfur hydrolysis agent has been subjected to hydrolysis treatment of blast furnace gas; and the specific surface area of the broken powder of the organic sulfur hydrolysis agent waste agent is 180-240 m 2 / g, the pore volume is 0.3-0.5 mL / g, and the particle size is 160-320 mesh.

[0017] Preferably, the method for preparing a mercury removal agent from desulfurization waste is characterized in that the activated carbon desulfurization waste agent is a desulfurization agent obtained by impregnating, drying, and calcining 75-95 parts by weight of an activated carbon carrier and 5-40 parts by weight of an alkali metal or a transition metal (alkaline earth metal), and the waste agent is obtained after the desulfurization agent has been subjected to desulfurization of blast furnace gas, refinery gas, or coke oven gas; the sulfur capacity of the activated carbon desulfurization waste agent is 5-12%, the specific surface area of the broken powder is 180-240 m 2 / g, the pore volume is 0.3-0.5 mL / g, and the particle size is 160-320 mesh.

[0018] Preferably, the skeleton material is a powder with a specific surface area of 180-240 m 2 / g, a pore volume of 0.3-0.5 mL / g, and a particle size of 160-320 mesh.

[0019] Preferably, the aluminum sol is an acidic aluminum sol, and the content of pseudoboehmite in the aluminum sol is 30-50wt%.

[0020] Preferably, the extruding or rolling in step (5) is to extrude the material after wet mixing in step (4) into a shape of a cylinder, a three-leaf clover or a four-leaf clover, and the diameter or equivalent diameter of the extruded material is 3-4 mm and the length is 6-8 mm.

[0021] A method for mercury removal treatment using a mercury removal agent, comprising the following steps:

[0022] I, using the method for preparing a mercury removal agent from the desulfurization waste to prepare the mercury removal agent.

[0023] II, laying a layer of refractory porcelain balls at the bottom of the bed of the mercury removal reactor, then laying the mercury removal agent prepared in step I on the top of the refractory porcelain balls, and then setting a layer of elastic mesh on the top of the mercury removal agent to fix the mercury removal agent.

[0024] III, setting the bed temperature of the mercury removal reactor to 10-350℃ and the pressure to normal pressure-8.0 MPa.

[0025] IV, discharging the raw material gas into the mercury removal reactor from the raw material gas inlet arranged at the bottom of the side of the mercury removal reactor, and the concentration of the raw material gas discharged from the raw material gas inlet is 1-200 μg / Nm 3 After the mercury removal and purification, the gas is discharged from the gas outlet arranged at the top of the mercury removal reactor.

[0026] V, a gas detection branch pipeline is arranged on the mercury removal reactor, and when the mercury concentration in the gas in the gas detection branch pipeline is detected to be greater than or equal to a set threshold value, the existing mercury removal agent is removed and replaced with a fresh mercury removal agent.

[0027] Preferably, the amount of the mercury removal agent laid in step II is set according to the gas amount of the raw material gas, specifically to ensure that the space velocity of the mercury removal agent is 500-1000 h -1 .

[0028] Preferably, the raw material gas is flue gas of a coal-fired power plant, waste incineration exhaust gas, sintering flue gas, refinery gas, smelting exhaust gas, electronic industry exhaust gas, caustic soda and polyvinyl chloride industry exhaust gas.

[0029] Preferably, the pipe diameter of the gas detection branch pipeline is and a ball valve is arranged on the gas detection branch pipeline.

[0030] Preferably, in step V, the mercury content in the gas in the gas detection branch pipeline is measured by a cold atomic fluorescence mercury analyzer.

[0031] Preferably, in step V, the set threshold value is 9-12 μg / Nm 3 .

[0032] The technical effect of the present application is that:

[0033] 1. Through a large number of studies, it is found that in the selective and hydrogen sulfide reaction blast furnace gas fine desulfurization technology, the precipitate copper sulfide obtained after desulfurization treatment by the method of using fresh copper sulfate solution and circulating copper sulfide solution as desulfurization liquid is flocculent structure, and by reasonably controlling the concentration of copper sulfide solution and reasonably selecting blast furnace gas with relatively low concentration of hydrogen sulfide for treatment, due to the relatively low concentration of hydrogen sulfide and the relatively low concentration of copper sulfate solution, the rate of generating flocculent solid precipitate (copper sulfide product) is slow, the crystal grain growth rate is slow, the product particle size is small, and the exposed active point is more, under the same condition of active component copper sulfide content, the outlet mercury concentration of the prepared mercury removal agent is low, and the mercury removal rate is high. And the flocculent solid precipitate obtained by this method has high purity of copper sulfide and basically no cuprous sulfide, so that the mercury removal efficiency of the finally prepared mercury removal agent is improved.

[0034] 2. The present application uses the desulfurization product copper sulfide as the main active component of the mercury removal agent, and also as the raw material of the mercury removal agent, which can recycle the desulfurization waste. Since the flocculent solid precipitate of copper sulfide used in the present application is the desulfurization waste product of a specific desulfurization treatment method, the overall production process has the advantage of low cost. Compared with the existing preparation process of copper sulfide, the present application does not need to go through a series of synthesis reactions of copper compounds, ethylenediamine, thiourea, ammonia and other substances, nor does it need to obtain copper sulfide by sulfidizing copper compounds with sulfides. The production process does not produce unpleasant odor, which can ensure the safety and health of the working environment of workers, thereby improving the environmental friendliness (i.e. recycling the desulfurization waste and not causing environmental pollution by re-preparation).

[0035] 3. By specific proportioning of the specific flocculent precipitate obtained by the specific desulfurization method, the specific skeleton material and the binder, the obtained mercury removal agent has the technical effects of high mercury removal efficiency and high mercury capacity. The aggregate uses hydrolysis agent waste and / or activated carbon desulfurization waste, and the carrier of the hydrolysis agent waste is mainly prepared from high specific surface and high pore volume alumina material. The broken hydrolysis agent waste still has the advantages of high specific surface and high pore volume as the mercury removal agent aggregate, which can improve the mercury removal efficiency of the mercury removal agent. The activated carbon desulfurization waste contains elemental sulfur generated by desulfurization in the pore channel, and the elemental sulfur in the pore channel has the effect of coordinating mercury removal. Especially by reasonably matching the proportion of the skeleton material and the copper sulfide material, the skeleton material and the specific flocculent copper sulfide play a synergistic effect in mercury removal, which improves the mercury capacity of the mercury removal agent. By setting the specific space velocity, temperature, pressure and other parameters of the mercury removal agent prepared by the specific process of the present application, the mercury removal rate and mercury capacity of the mercury removal agent prepared by the specific process of the present application are greatly improved. DETAILED DESCRIPTION

[0036] The technical solution of the present invention will be further described in conjunction with the embodiments. Unless otherwise specified, each feature is merely one example of a series of equivalent or similar features. These embodiments are merely for the purpose of aiding understanding the present invention, and those skilled in the art should understand that they are only intended to help in understanding the invention and should not be considered as specific limitations on the invention.

[0037] Example 1

[0038] A method for preparing a mercury removal agent from desulfurization waste includes the following steps:

[0039] (1) A steel plant 1080m 3 blast furnace gas flow rate 400,000 m³ 3 / h, the hydrogen sulfide concentration in the blast furnace gas after hydrolysis is approximately 78–88 mg / m³. 3 The gas temperature is 45℃. Prepare 1000m³ of gas. 3 A copper sulfate solution with a molar concentration of 0.015 mol / L is fed into a turbid water circulation tank, and then into the spray guns of the 2nd, 3rd, and 4th layers of the desulfurization tower. Blast furnace gas is discharged into the desulfurization tower from the bottom, where it reacts counter-currently with the copper sulfate solution sprayed from below to carry out a desulfurization reaction. Simultaneously, a fresh copper sulfate solution of 0.19 mol / L is prepared. This solution is sprayed through the atomizing spray gun in the first layer, reacting with the circulating copper sulfide solution sprayed from the lower spray gun to further remove hydrogen sulfide. The liquid produced after desulfurization, carrying a flocculent precipitate mainly composed of copper sulfide, is discharged from the spray liquid outlet at the bottom of the tower. The filtered flocculent solid precipitate is enriched; the concentration of the circulating copper sulfate solution in the circulation tank is adjusted to 0.015 mol / L for recycling.

[0040] (2) The flocculent solid precipitate collected from desulfurization is transported to a grinding equipment via a belt conveyor to grind the copper sulfide into 160-320 mesh powder, resulting in a powder with a specific surface area of ​​36 m². 2 / g, copper sulfide purity is 98%.

[0041] (3) Grind the waste desulfurization hydrolysate of blast furnace gas into 160-mesh powder and prepare an aluminum sol with a boehmite content of 40wt% for later use.

[0042] (4) Add copper sulfide powder, blast furnace gas desulfurization hydrolysis agent waste powder, and aluminum sol to the mixer in a mass ratio of 1.5:7.6:2 and dry mix for 15 minutes to make the materials evenly dispersed.

[0043] (5) Spray 24wt% water onto the dry-mixed material, wet mix for 15 minutes, and then extrude to form the material.

[0044] (6) drying at 120°C to obtain a strip-shaped mercury removal agent with a diameter of 3-4 mm and a water content of less than 3%.

[0045] The method for removing mercury by using the mercury removal agent prepared above comprises the following steps:

[0046] I. Mercury removal agent use conditions: 1.0 MPa, 50°C mercury-containing raw material gas, mercury concentration 90 μg / Nm 3 , from the side and bottom of the reactor, mercury removal space velocity 500 h -1 .

[0047] II. The mercury removal agent produced from the desulfurization product is packed in a mercury removal reactor, and fireproof porcelain balls are laid at the bottom of the mercury removal reactor; the upper part of the mercury removal reactor is covered on the top of the mercury removal agent bed layer by a stainless steel wire mesh, and the purified gas is discharged from the top of the reactor and enters the next unit through a pipeline.

[0048] The mercury concentration at the inlet and outlet is measured, and the saturated adsorption capacity of the mercury removal agent is calculated.

[0049]

[0050] Example 2

[0051] (1) The total hydrogen sulfide concentration at the inlet of the blast furnace gas fine desulfurization is 90-150 mg / m 3 , the concentration of the circulating copper sulfate solution is 0.042 mol / L, and the remaining operating conditions are the same as in Example 1.

[0052] (2) The flocculent precipitate (mainly copper sulfide) collected by desulfurization is transported to a grinding device by a belt conveyor, and the copper sulfide is ground into a powder with a mesh size of 160-320, so that the specific surface area of the powder is 33 m 2 / g (measured by specific surface area), and the purity of the copper sulfide is 98%.

[0053] (3) The activated carbon desulfurization waste agent is crushed and ground into a powder with a mesh size of 160-320, so that the specific surface area of the powder is 182 m 2 / g.

[0054] (4) The copper sulfide powder, activated carbon desulfurization waste agent powder, and carboxymethyl cellulose are added into a mixer at a mass ratio of 1:8:1, dry mixing for 12 minutes to make the materials uniformly dispersed; the specific surface area of the activated alumina is 180 m 2 / g, and the particle size is 200 mesh.

[0055] (5) 30% water is sprayed into the dry mixed materials, and wet mixing is performed for 20 minutes, and then extrusion molding is performed.

[0056] (6) Drying at 150°C to obtain a strip-shaped mercury removal agent with a diameter of 3-4 mm and a water content of less than 3%.

[0057] The method for mercury removal treatment using the mercury removal agent prepared above comprises the following steps:

[0058] The mercury removal process step design is the same as that of Example 1, and the specific parameters are as follows:

[0059] The mercury removal agent use conditions are as follows: 1.0 MPa, 175℃ of the mercury-containing raw material gas, and the mercury concentration is 120 μg / Nm 3 , entering from the side bottom of the reactor, and the mercury removal space velocity is 500 h -1 .

[0060] Example 3

[0061] (1) The process of obtaining flocculent precipitate by fine desulfurization of blast furnace gas is the same as that of Example 1, except that the molar concentration of the circulating copper sulfate solution is 0.01 mol / L, and the molar concentration of the fresh copper sulfate solution is 0.25 mol / L.

[0062] (2) The flocculent precipitate collected by desulfurization (mainly copper sulfide) is transported to a grinding device by a belt conveyor, and the copper sulfide is ground into a 160-320 mesh powder, and the specific surface area of the powder is 36 m 2 / g.

[0063] (3) The activated carbon desulfurization waste agent is crushed and ground into a 160-320 mesh powder, and the specific surface area of the powder is 182 m 2 / g.

[0064] (3) The copper sulfide powder, the activated carbon desulfurization waste agent powder, and the cement are added into a mixer in a mass ratio of 1.5:7:1.5, and dry mixing is performed for 10 minutes to uniformly disperse the materials;

[0065] (4) 25% water is sprayed into the dry mixed materials, and wet mixing is performed for 15 minutes, and then extrusion molding is performed.

[0066] (5) Drying is performed at 140℃ until the water content is less than 3%, and a strip-shaped mercury removal agent with a diameter of 3-4 mm is obtained.

[0067] The method for mercury removal treatment using the mercury removal agent prepared above comprises the following steps:

[0068] The mercury removal process step design is the same as that of Example 1, and the specific parameters are as follows:

[0069] The mercury removal agent use conditions are as follows: 2.0 MPa, 110℃ of the mercury-containing raw material gas, and the mercury concentration is 75 μg / Nm 3 , entering from the side bottom of the reactor, and the mercury removal space velocity is 1000 h -1 .

[0070] Comparative Example 1

[0071] The copper ammonia solution is prepared by dissolving basic copper carbonate in ammonia water, and then dried at 100°C to obtain copper diammonium carbonate, which is calcined at 220°C to obtain nano copper oxide. The nano copper oxide is immersed in an ammonia sulfide solution with a sulfur content of 8wt%, and then dried after leaching to obtain copper sulfide; the specific surface area of the copper sulfide is 28.9m 2 / g.

[0072] The copper sulfide is mixed with active alumina powder and cement at a mass ratio of 1.2:8:1, and then a CMC aqueous solution is added for rolling and drying to obtain a 3-6mm copper sulfide mercury removal agent.

[0073] The mercury removal performance of the mercury removal agent prepared in Comparative Example 1 is evaluated by on-site side-line experiments, and the mercury removal treatment step parameters are the same as those in Example 2.

[0074] Comparative Example 2

[0075] A 2L, 0.5mol / L copper acetate solution is mixed with a 1L, 1mol / L ethylenediamine solution, and then 2L, 4mol / L ammonia water is added to obtain a premixed solution; 1.5L, 1mol / L thiocyanate solution is added to the premixed solution and mixed uniformly to obtain an impregnation solution; 1kg of 5A molecular sieve is immersed in the impregnation solution at 25°C for 2h, drained for 1h, activated at 80°C for 4h, and then dried at 110°C for 3h to obtain a mercury removal agent.

[0076] The mercury removal performance of the mercury removal agent prepared in Comparative Example 2 is evaluated by on-site side-line experiments, and the mercury removal treatment step parameters are the same as those in Example 3.

[0077] Comparative Example 3

[0078] The other settings of this comparative example are the same as those in Example 2, except that the skeleton material is selected to be 160-320 mesh, 180m 2 / g ordinary activated carbon powder, which is treated by the same steps as in Example 2 to obtain a mercury removal precision of 0.75ug / Nm 3 , and a mercury capacity of 21.7mg / g. It can be seen that the use of the specific skeleton material of the present application will result in a decrease in mercury removal precision, and more significantly, the mercury capacity decreases from 25.2mg / g to 21.7mg / g compared with Example 2.

[0079] Comparative Example 4

[0080] The other settings of this comparative example are the same as those in Example 2, except that the skeleton material is an activated carbon desulfurization agent waste agent with a weight fraction of 45, the binder is 40 parts by weight, and the flocculent precipitate collected during desulfurization is 15 parts by weight, which is treated by the same steps as in Example 2 to obtain a mercury removal precision of 0.95ug / Nm3 The mercury capacity is 20.2 mg / g, so it can be seen that if the proportion of the skeleton material is not selected according to the present application, the mercury removal agent will have low accuracy, be easy to penetrate, and have low mercury capacity. This is mainly because the mercury removal agent provides active sites, and when the skeleton material is reduced, the specific surface area obtained is reduced, and the active sites that can be provided are reduced, so the mercury removal accuracy is reduced; in addition, the elemental sulfur on the surface of the spent activated carbon desulfurization agent can have a synergistic effect with the copper sulfide mercury removal, and when the skeleton material is reduced, the mercury capacity is also reduced.

[0081] Comparative Example 5

[0082] The other settings of the present comparative example are the same as those of Example 1, except that the hydrogen sulfide concentration in the blast furnace gas after hydrolysis in step (1) is about 150-180 mg / m 3 The molar concentration of the circulating copper sulfate solution is 0.06 mol / L, and the molar concentration of the fresh copper sulfate solution is 0.96 mol / L. The other settings are the same as those of Example 1, and the specific surface area of the flocculent copper sulfide material detected is 25.6 m 2 / g, the content of copper sulfide is 97%, and after the same mercury removal treatment as in Example 1, the mercury removal accuracy at the initial stage of operation is 1.2 μg / Nm 3 After 168 h of experiment, the mercury removal accuracy decreases to 3.1 μg / Nm 3 Thus, it can be seen that if the hydrogen sulfide content is slightly high and / or the concentration of the copper sulfate solution is increased, the specific surface area of the copper sulfide material obtained by the reaction is small, the mercury removal outlet accuracy is small, the mercury removal efficiency decreases rapidly, and finally the mercury removal agent is rapidly deactivated.

[0083] The specific surface area, mercury capacity, and mercury removal accuracy of the mercury removal agent in the test results of each example and comparative example are shown in Tables 1 and 2.

[0084] Table 1

[0085] Example 1 Example 2 Example 3 Copper sulfide specific surface area, m 2 / g]]> 36 33 36 Copper sulphide purity % 98％ 98％ 98％ Mercury removal accuracy, pg / m 3 ]] 0.33 μg / Nm 3 ]] 0.65 μg / Nm 3 ]] 0.12 μg / Nm 3 ]] Mercury capacity, mg / g 25.2 21.3 27.0

[0086] Table 2

[0087] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Copper sulfide specific surface area, m 2 / g]]> 28.9 / 33 33 25.6 Copper sulphide purity % 92 95 98％ 98％ 97％ Mercury removal accuracy, pg / m 3 ]] 0.77 μg / Nm 3 ]] 0.86 μg / Nm 3 ]] 0.75 ug / ug / Nm 3 ]] 0.95 μg / Nm 3 ]] 3.1 μg / m 3 ]] Mercury capacity, mg / g 18.6 23.0 21.7 20.2 /

[0088] As shown in Table 1 and Table 2 can be obtained, the implementation of 1~3 using low solution concentration synthesis, the reaction rate is slow example 1 get copper sulfide process steps simple, material consumption, low cost, the material specific surface area of copper sulfide is large, the purity of copper sulfide is high. And the comparative example 1 in the synthesis of copper sulfide, there will be cuprous sulfide to cause the purity to drop, influence mercury removal precision;In addition, due to the fast reaction speed product grain big, the specific surface area of copper sulfide product is small, the pore structure is small, in the high air velocity, the outlet precision will also be affected, mercury capacity is low. And in the comparative example 1 and comparative example 2 in the production process, the raw material ammonia, thiourea exist smell, strong toxicity of security risks, the operation condition is not suitable for quantification production, harm worker health.

[0089] The art-known techniques involved in the present application are not described in detail. The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for producing a mercury removal agent from desulfurization waste, characterized by, Comprising the following steps: (1) A fresh copper sulfate solution with a concentration of 0.1-0.5 mol / L and a circulating copper sulfate solution with a concentration of 0.008-0.05 mol / L are layered and jointly sprayed into a desulfurization tower device to perform reverse contact with blast furnace gas with a hydrogen sulfide concentration of 40-150 mg / m 3 The desulfurization liquid discharged from the bottom of the desulfurization tower device is filtered to obtain flocculent solid precipitates and a circulating stock solution. The supernatant of the circulating stock solution is discharged into a circulating pool to configure a circulating copper sulfate solution. Fresh copper sulfate solution is added to the circulating pool to maintain the concentration of the circulating copper sulfate solution discharged from the circulating pool into the desulfurization tower device at 0.008-0.05 mol / L. (2) the flocculent solid precipitate obtained in step (1) is placed into a grinder to grind to obtain a copper sulfide material with a particle size of 160-320 mesh and a specific surface area of 30-38 m 2 / g; the purity of the copper sulfide in the copper sulfide material is 97-99 wt%, and the content of cuprous sulfide is less than 0.5 wt%. (3) 60-80 parts by weight of the framework material, 10-20 parts by weight of the binder and 10-20 parts by weight of the copper sulfide material obtained in step (2) are added to a dry mixing device, and dry mixing is carried out for 10-15 minutes to obtain a dry mixed material; (4) The dry mixed material obtained in step (3) is continuously mixed under the condition of continuously spraying water, and the wet mixing time is 15-20 minutes, and the sprayed water is 20-30 parts by weight; (5) The material after wet mixing in step (4) is extruded or rolled into a ball; (6) The material after molding in step (5) is dried at a temperature of 100-150℃, so that the water content of the material is less than or equal to 3wt%, to obtain a mercury removal agent product.

2. The method of claim 1, wherein the desulfurization waste is prepared by a method comprising: In step (1), the fresh copper sulfate solution is sprayed in the upper layer, and the circulating copper sulfate solution is sprayed in the lower layer. ​ 3. The method of claim 1, wherein the desulfurization waste is prepared by a method comprising: mixing the desulfurization waste with a base to form a mixture; and heating the mixture to a temperature of 50°C to 100°C for 1 hour to 10 hours. The framework material is one or both of the powder after crushing of the organic sulfur hydrolysis agent waste or the powder after crushing of the activated carbon desulfurization waste; the binder is one or more of kaolin, portland cement, carboxymethyl cellulose, and aluminum sol.

4. The method of claim 3, wherein the desulfurization waste is prepared by a method comprising: mixing the desulfurization waste with a base to form a mixture; and heating the mixture to a temperature of 50°C to 100°C for 1 hour to 10 hours. The organic sulfur hydrolysis agent waste agent is 55-90 parts by weight of activated alumina and 20-50 parts by weight of a salt of an alkali metal or an alkali of an alkali metal, which is obtained after calcination of the organic sulfur hydrolysis agent after the hydrolysis treatment of the blast furnace gas, and the specific surface area of the powder of the broken organic sulfur hydrolysis agent waste agent is 180-240 m 2 / g, the pore volume is 0.3-0.5 mL / g, and the particle size is 160-320 mesh.

5. The method of claim 3, wherein the desulfurization waste is prepared by a method comprising: mixing the desulfurization waste with a base to form a mixture; and heating the mixture to a temperature of 50°C to 100°C for 1 hour to 10 hours. The active carbon desulfurization waste agent is a waste agent obtained after desulfurization of blast furnace gas, refinery gas or coke oven gas, and is composed of 75-95 parts by weight of active carbon carrier and 5-40 parts by weight of alkali metal or transition metal impregnated and dried and calcined desulfurization agent; the sulfur capacity of the active carbon desulfurization waste agent is 5-12%, the specific surface area of the crushed powder is 180-240 m 2 / g, the pore volume is 0.3-0.5 mL / g, and the particle size is 160-320 mesh.

6. The method of claim 3, wherein the desulfurization waste is prepared by a process comprising: mixing the desulfurization waste with a base to form a mixture; and heating the mixture to a temperature of 50°C to 100°C for 1 hour to 10 hours. The aluminum sol is an acidic aluminum sol, and the content of pseudoboehmite in the aluminum sol is 30-50wt%.

7. The method of claim 5, wherein the desulfurization waste is prepared by a method comprising: mixing the desulfurization waste with a reducing agent; and heating the mixture to a temperature of 300 to 600°C in a non-oxidizing atmosphere. The extrusion or rolling in step (5) is to extrude the material after wet mixing in step (4) into a shape of one of a cylinder, a trilobal shape or a quadrilobal shape, and the diameter or equivalent diameter of the molded material is 3-4mm, and the length is 6-8mm.

8. A method for mercury removal treatment using a mercury removal agent, characterized by, Comprising the following steps: I, using the method for preparing a mercury removal agent from a desulfurization waste according to any one of claims 1-7 to prepare the mercury removal agent; II, a layer of refractory porcelain balls is laid at the bottom of the bed layer of the mercury removal reactor, then the mercury removal agent prepared in step I is laid on the upper part of the refractory porcelain balls, and then a layer of elastic mesh is arranged on the top of the mercury removal agent to fix the mercury removal agent; III, the bed layer temperature of the mercury removal reactor is set to 10-350℃, and the pressure is set to normal pressure-8.0MPa; IV, the raw material gas is discharged into the mercury removal reactor from a raw material gas inlet provided at the bottom of the side of the mercury removal reactor, the concentration of the raw material gas discharged from the raw material gas inlet is 1-200 µg / Nm 3 , and the gas after mercury removal and purification is discharged from a gas outlet provided at the top of the mercury removal reactor; V, a gas detection branch pipeline is arranged on the mercury removal reactor, and when the mercury concentration in the gas in the gas detection branch pipeline is detected to be greater than or equal to a set threshold value, the existing mercury removal agent is removed and replaced with a fresh mercury removal agent.

9. The method for mercury removal treatment using a mercury removal agent according to claim 8, wherein The packing and laying amount of the mercury removal agent in step II is set according to the gas amount of the raw material gas, specifically to ensure that the space velocity of the mercury removal agent is 500-1000h -1 , and the raw material gas is coal-fired power plant flue gas, waste incineration exhaust gas, sintering flue gas, refinery gas, smelting exhaust gas, electronic industry exhaust gas, caustic soda and polyvinyl chloride industry exhaust gas.

10. The method for mercury removal treatment using a mercury removal agent according to claim 8, characterized by, The pipe diameter of the gas detection branch pipeline is ø11~15mm, and a ball valve is arranged on the gas detection branch pipeline; in step V, the mercury content is measured by using a cold atomic fluorescence mercury analyzer to detect the gas in the gas detection branch pipeline; in step V, the threshold value is set to 9~12µg / Nm 3 .

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