Disclosure of Invention
In order to solve the above problems, a first aspect of the present invention provides a process for capturing and utilizing carbon dioxide and comprehensively utilizing energy, comprising the steps of: (1) dedusting the flue gas in the dedusting device; (2) removing impurities from the flue gas in the desulfurization and denitrification device; (3) cooling the flue gas in the first heat exchange device; (4) removing carbon dioxide in the flue gas in the carbon capture device to obtain carbon capture absorption liquid; (5) heating the carbon capture absorption liquid in the first heat exchange device and the second heat exchange device and performing desorption in the desorption device to obtain desorption liquid and carbon dioxide mixed gas; (6) cooling and recycling desorption liquid in the first heat exchange device; (7) and (3) mineralizing the mixed gas of the solid waste and the carbon dioxide in a mineralizing reaction device.
As a preferable scheme, the flue gas is at least one of power plant flue gas, steel plant blast furnace flue gas, converter flue gas, refining furnace flue gas and lime kiln furnace flue gas; the volume fraction of carbon dioxide in the flue gas is 5-80%.
Preferably, the dust removing device is any one of a cloth bag dust removing device, a cyclone dust removing device, a wet dust removing device and an electrostatic dust removing device.
As a preferable scheme, the dust removing device is any one of a bag dust removing device and a cyclone dust removing device.
As a preferable scheme, the desulfurization and denitrification device is a desulfurization and denitrification membrane group formed by connecting 100-300 single ceramic membrane components in series and/or in parallel; the ceramic membrane raw material in the single ceramic membrane component of the desulfurization and denitrification device is at least one of alumina, zirconia, titania and zinc oxide; the water contact angle of the ceramic membrane in the desulfurization and denitrification device is 10-60 degrees.
During use, the ceramic membrane 2 in the single ceramic membrane module 1 forming the desulfurization and denitrification apparatus is located in the middle of the central liquid phase 3 (first or second absorbent) and the gas phase 4 outside the membrane, wherein the liquid phase 3 and the gas phase 4 flow in a relatively countercurrent direction. In the carbon capture device and the desorption device, the ceramic membrane 2 and the liquid phase 3 and the gas phase in the single ceramic membrane module 1 are in the same structural position, but the specific compositions of the ceramic membrane 2, the liquid phase 3 and the gas phase 4 are different according to different functions.
Preferably, the ceramic membrane raw material in the single ceramic membrane module of the desulfurization and denitrification device is a mixture of titanium oxide and modified titanium oxide, and the mass ratio is 3-5: 1.
As a preferred embodiment, the preparation method of the modified titanium oxide comprises the following steps: (1) dissolving succinic anhydride in a DMF solution, adding (3-aminopropyl) triethoxysilane, and heating and stirring for 1-2 hours at the water bath temperature of 50-80 ℃; (2) dropwise adding a DMF (dimethyl formamide) solution containing titanium dioxide into the reaction solution, continuously stirring for reacting for 2-3 hours, and centrifuging to obtain pretreated titanium dioxide particles; (3) and then mixing 2-methylimidazole and zinc nitrate for reaction, adding ethanol, carrying out ultrasonic polymerization for 2-3 hours in a 400W water bath ultrasonic device, adding pretreated titanium dioxide particles, continuing to carry out ultrasonic reaction for 1-2 hours, washing and drying the obtained product after the reaction is finished, and thus obtaining the modified titanium oxide.
As a preferable scheme, in the preparation method of the modified titanium oxide, the mass ratio of the pretreated titanium oxide to the 2-methylimidazole and the zinc nitrate is 4-5: 10-15: 4-5; the total time of the ultrasonic reaction is not more than 4 hours.
As a preferable scheme, the first heat exchange device is at least one or more of a shell-and-tube heat exchanger, a spiral tube heat exchanger, a shell-and-tube heat exchanger and a plate heat exchanger; the second heat exchange device is one or more of a shell-and-tube heat exchanger, a spiral tube heat exchanger, a shell-and-tube heat exchanger and a plate heat exchanger.
As a preferable scheme, the carbon capturing device is a carbon dioxide capturing group formed by connecting 100-300 single ceramic membrane modules in series and/or in parallel; the ceramic membrane raw material in the single ceramic membrane component of the carbon capture device is at least one of alumina, zirconia, titania and zinc oxide; the water contact angle of the ceramic membrane in the carbon capturing device is 150-165 degrees.
Preferably, the ceramic membrane raw material in the single ceramic membrane module of the carbon capture device is a mixture of alumina and modified alumina, and the mass ratio of the alumina to the modified alumina is 3-5: 1.
As a preferable scheme, the preparation method of the modified alumina comprises the following steps: (1) mixing alumina and a silane coupling agent, heating to 70-80 ℃, and stirring for 2-3 hours; (2) and then mixing the treated aluminum oxide with 2-methylimidazole and zinc nitrate for reaction, adding water or a methanol solution, reacting and stirring for 4-6 hours at the temperature of 60-80 ℃, and washing and drying the obtained product to obtain the catalyst.
As a preferable scheme, in the preparation method of the modified alumina, the mass ratio of the pretreated alumina to the 2-methylimidazole and the zinc nitrate is 1-2: 10-15: 4-5; the total time of the mixing reaction is not less than 4 hours.
In this application, through modifying in the time of the raw materials to the ceramic membrane in SOx/NOx control device and the carbon capture device, improved the impurity separation selectivity of ceramic membrane to the flue gas to have good heat conductivility, further improvement to the reservation of flue gas or carbon dioxide heat energy at flue gas edulcoration in-process, make the entrapment system can break away from the support of outside heat source energy completely. The applicant believes that: by adopting the preparation method of the modified titanium oxide, and adding excessive titanium oxide, the influence of a microcosmic titanium oxide coating frame material can be formed in the prepared composite particle material, so that the composite particles actually form a titanium oxide coating microsphere structure, the hydrophilic selection of the surfaces of the composite particles is ensured, better heat-conducting property can be further provided through the frame material, and the ceramic membrane has excellent hydrophilicity and selective permeability of sulfur oxide substances. On the other hand, by adopting the preparation method of the modified alumina and adding a small amount of alumina, a frame material coated alumina particle can be formed in the modification process, even if the coating is unsuccessful, polycrystal-deposited large-framework particles can be formed due to a long reaction time, and the hydrophobic surface conforming to the particles is exposed, so that the heat-conducting hydrophobic particles are actually formed, but the ceramic membrane has a good compatibility effect due to the surface connection of the alumina, so that the hydrophobicity and the heat-conducting effect of the ceramic membrane can be greatly improved, and the ceramic membrane embrittlement phenomenon can be reduced.
The specific preparation method of the ceramic membrane is not specifically limited in the present application, and those skilled in the art can prepare the ceramic membrane by using a common preparation method in the field of ceramic membranes such as a sol-gel method and a vapor deposition method according to actual needs.
As a preferable scheme, the desorption device is a carbon dioxide desorption group formed by connecting 100-300 single ceramic membrane modules in series and/or in parallel; the ceramic membrane raw material in the single ceramic membrane component of the desorption device is at least one of alumina, zirconia, titania and zinc oxide.
As a preferable scheme, the carbon dioxide mixed gas further comprises water vapor; the volume fraction of the water vapor in the carbon dioxide mixed gas is 6-20%.
Preferably, the solid waste is at least one of steel slag, furnace ash, iron slag, fly ash, bottom ash, fly ash, red mud, waste cement, tailing sand and ore raw materials.
In a preferable embodiment, the solid waste contains calcium oxide, calcium hydroxide, calcium silicate, amorphous silica gel, magnesium oxide, and magnesium hydroxide in an amount of 40 wt% or more.
As a preferable scheme, the specific operation of the step (1) is as follows: introducing the flue gas into a dust removal device for flue gas dust removal, wherein the temperature of the flue gas after dust removal is 200-300 ℃.
As a preferable scheme, the rear end of the desulfurization and denitrification device further comprises a baffle structure; the SCR denitration catalyst is installed on the baffle structure at the rear end of the device, ammonia gas is introduced into the desulfurization and denitration device during use, and the ammonia gas is absorbed by the SCR denitration catalyst on the baffle at the rear end and is used for denitration reaction.
As a preferable scheme, the specific operation of the step (2) is as follows: directly inputting the dedusted flue gas into a desulfurization and denitrification device, wherein the flue gas and a first absorbent in a desulfurization and denitrification device pipe adopt a cross flow-vortex-cross flow flowing mode, and sulfur oxides in the flue gas are absorbed by the first absorbent through a membrane hole at the front end of the desulfurization and denitrification device; and nitrogen oxides in the desulfurization flue gas are catalyzed by the SCR denitration catalyst on the baffle plate at the rear end of the desulfurization and denitration device to generate nitrogen.
In a preferred embodiment, the first absorbent is any one of a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution, seawater, and water.
As a preferable scheme, the specific operation of the step (3) is as follows: and (3) inputting the flue gas subjected to the step (2) into a first heat exchange device for cooling treatment, and cooling to 30-50 ℃.
As a preferable scheme, the specific operation of the step (4) is as follows: and (4) conveying the flue gas subjected to the step (3) to a carbon capture device, enabling the flue gas to reversely flow with a second absorbent in the carbon capture device, and enabling the carbon dioxide to react with the second absorbent for absorption to obtain carbon capture absorption liquid.
In a preferred embodiment, the second absorbent is at least one of an alcohol amine and a cyclic organic amine.
As a preferable scheme, the specific operation of the step (5) is as follows: and conveying the carbon capture absorption liquid absorbing the carbon dioxide to a second heat exchange device, heating to 50-60 ℃, conveying to a first heat exchange device, heating to 80-100 ℃, introducing into a desorption device, separating out the carbon dioxide in the carbon capture absorption liquid to obtain desorption liquid and carbon dioxide mixed gas, and storing for later use respectively.
As a preferable scheme, the temperature of the carbon dioxide mixed gas is 80-100 ℃, and the volume fraction is 60-100%.
As a preferable scheme, the specific operation of the step (6) is as follows: and conveying the desorption liquid to a first heat exchange device, cooling to 20-40 ℃, and then inputting to a carbon capture device for recycling.
As a preferable scheme, the specific operation of the step (7) is as follows: stirring and mixing the solid waste, putting the mixture into a mold, and pressing the mixture into a blank under the pressure of 10-400 MPa; and (2) feeding the blank body into an aging device for aging, feeding the aged blank body into a mineralization reaction device, and directly introducing trapped carbon dioxide mixed gas into the mineralization reaction device for mineralization reaction, wherein the mineralization reaction temperature is 60-150 ℃, the mineralization time is 30-360 min, the mineralization pressure is 0.1-10 bar, and the mineralization humidity is 40-80%.
As a preferable scheme, the heat required by the mineralization reaction temperature in the step (7) is provided by carbon dioxide mixed gas.
As a preferable scheme, the water vapor required for the mineralization reaction humidity in the step (7) is provided by water vapor in the carbon dioxide mixed gas.
Preferably, the solid waste in the step (7) is stirred and mixed at a water-cement ratio L/S of 0.05-0.3.
The second aspect of the invention provides an application of the carbon dioxide capture and utilization and energy comprehensive utilization process, which comprises an application of the carbon dioxide capture and utilization and energy comprehensive utilization process in a carbon dioxide emission reduction process.
Has the advantages that:
1. compared with the traditional heat loss of absorption tower type desulfurization and denitrification and the problem that a common organic membrane component is easy to lose, the carbon dioxide capture utilization and energy comprehensive utilization process provided by the application has the advantages that the adopted ceramic membrane material is acid-base resistant (pH is 0-14) and high-temperature resistant (below 1000 ℃), and can be completely suitable for high-temperature flue gas treatment from different sources; the gas-liquid separation regulation and control characteristics of the membrane absorption device determine that the heat of the flue gas is kept while the flue gas is treated. The retained heat can further provide good heat source energy for the mineralization of carbon dioxide, thereby reducing the supply of extra energy.
2. The process for capturing and utilizing carbon dioxide and comprehensively utilizing energy provided by the application realizes flue gas desulfurization and denitrification treatment and CO comprehensive utilization2The method for trapping and utilizing integrates and recovers the heat in the high-temperature flue gas to the maximum extent, and is used for desorption and mineralization utilization of rear-end carbon dioxide, so that the trapping and utilization efficiency is greatly improved, the overall process time is shortened, and the energy consumption is reduced.
3. The process for capturing and utilizing carbon dioxide and comprehensively utilizing energy uses pure bulk solid waste as a raw material and CO after capture2The carbonization maintenance is carried out, the high-quality building material product is prepared under certain process conditions, the high-efficiency resource utilization of industrial solid waste and urban solid waste can be effectively realized, the total carbon emission of the prepared building material product is reduced by more than 50 percent compared with the traditional silicate cement product, and the method also has an important promotion effect on the low-carbon development of the building material industry in China.
4. The utility model provides a technique is utilized and is used multipurposely to entrapment of carbon dioxide, through the selectivity modification to the raw materials of the ceramic membrane in SOx/NOx control device and the carbon entrapment device, super hydrophilic and super hydrophobic ceramic membrane surface has effectively been formed, can form more effective single selectivity at desulfurization and carbon entrapment in-process, and further improvement the conversion and the transfer effect of flue gas energy, can be in the carbon dioxide mineralization reaction complete provide stable heat source by the heat of gas itself, ensure not have any external energy to support, realize the complete consumption utilization of flue gas heat in the complete meaning.
Detailed Description
Example 1
Example 1 in a first aspect, there is provided a process for carbon dioxide capture and energy integration, comprising the steps of: (1) introducing the flue gas into a dust removal device for flue gas dust removal, wherein the temperature of the flue gas after dust removal is 240 ℃; (2) directly inputting the dedusted flue gas into a desulfurization and denitrification device, wherein the flue gas and a first absorbent in a desulfurization and denitrification device pipe adopt a cross flow-vortex-cross flow flowing mode, and sulfur dioxide and sulfur trioxide in the flue gas are absorbed by the first absorbent through a membrane hole at the front end of the desulfurization and denitrification device; nitrogen oxides in the desulfurization flue gas are catalyzed by an SCR (selective catalytic reduction) denitration catalyst on a baffle plate at the rear end of the desulfurization and denitration device to generate nitrogen; (3) inputting the flue gas subjected to the step (2) into a first heat exchange device for cooling treatment, and cooling to 40 ℃; (4) conveying the flue gas subjected to the step (3) to a carbon capture device, enabling the flue gas to reversely flow with a second absorbent in the carbon capture device, and enabling carbon dioxide to react with the second absorbent for absorption to obtain carbon capture absorption liquid; (5) conveying the carbon capture absorption liquid absorbing the carbon dioxide to a second heat exchange device, heating to 55 ℃, then conveying to a first heat exchange device, heating to 100 ℃, then introducing into a desorption device, separating out the carbon dioxide in the carbon capture absorption liquid to obtain a desorption liquid and carbon dioxide mixed gas, and storing for later use; (6) conveying the desorption liquid to a first heat exchange device, cooling to 30 ℃, and then inputting the desorption liquid to a carbon capture device for recycling; (7) stirring and mixing the solid waste, putting the mixture into a mold, and pressing under 250MPa to prepare a blank; and (3) feeding the blank body into an aging device for aging, feeding the aged blank body into a mineralization reaction device, and directly introducing carbon dioxide mixed gas subjected to trapping and desorption into the mineralization reaction device for mineralization reaction, wherein the mineralization reaction temperature is 100 ℃, the mineralization time is 200min, the mineralization pressure is 6bar, and the mineralization humidity is 60%.
Wherein the flue gas is the flue gas of a blast furnace of a steel plant, and the volume fraction of carbon dioxide in the flue gas is 15%.
The dust removing device is a cyclone dust removing device; the rear end of the desulfurization and denitrification device also comprises a baffle plate structure; the SCR denitration catalyst is installed on the baffle structure at the rear end of the device, ammonia gas is introduced into the desulfurization and denitration device during use, and the ammonia gas is absorbed by the SCR denitration catalyst on the baffle at the rear end and is used for denitration reaction.
The desulfurization and denitrification device is a desulfurization and denitrification membrane group formed by connecting 160 single ceramic membrane components in series; the ceramic membrane raw material in the single ceramic membrane component of the desulfurization and denitrification device is a mixture of titanium oxide and modified titanium oxide, and the mass ratio is 3.5: 1.
The preparation method of the modified titanium oxide comprises the following steps (in parts by weight): (1) dissolving 5 parts of succinic anhydride in 50 parts of DMF solution, adding 3 parts of (3-aminopropyl) triethoxysilane, and heating and stirring at 70 ℃ of water bath temperature for 1.5 hours; (2) then, 80 parts of DMF solution containing 5 parts of titanium dioxide is dripped into the reaction solution, and the mixture is continuously stirred for reaction for 2.5 hours and then centrifuged to obtain pretreated titanium dioxide particles; (3) and then, mixing 15 parts of 2-methylimidazole and 5 parts of zinc nitrate for reaction, adding 200 parts of ethanol, carrying out ultrasonic polymerization for 2 hours in a 400W water bath ultrasonic device, adding 5 parts of pretreated titanium dioxide particles, continuing the ultrasonic reaction for 1.5 hours, and washing and drying the obtained product after the reaction is finished to obtain the modified titanium oxide.
The first heat exchange device and the second heat exchange device are both spiral tube type heat exchangers.
The carbon capture device is a carbon dioxide capture group formed by connecting 160 single ceramic membrane components in series; the ceramic membrane raw material in the single ceramic membrane component of the carbon capture device is a mixture of alumina and modified alumina, and the mass ratio is 3: 1; the preparation method of the modified alumina comprises the following steps (in parts by weight): (1) mixing 1.5 parts of alumina with 2 parts of silane coupling agent KH550, stirring and heating for 3 hours at 75 ℃; (2) and then mixing 1.5 parts of treated alumina with 15 parts of 2-methylimidazole and 5 parts of zinc nitrate for reaction, adding 300 parts of methanol solution, reacting together at 70 ℃, stirring for 5 hours, and washing and drying the obtained product to obtain the catalyst.
The desorption device is a carbon dioxide desorption group formed by connecting 160 single ceramic membrane components in series; the ceramic membrane raw material in the single ceramic membrane component of the desorption device is alumina; the preparation method of the ceramic membrane is a sol-gel method.
The carbon dioxide mixed gas also comprises water vapor; the volume fraction of the water vapor in the carbon dioxide mixed gas is 10 percent; the solid waste is fly ash, and the total content of calcium oxide, calcium hydroxide, calcium silicate, amorphous silica gel, magnesium oxide and magnesium hydroxide in the solid waste is 45 wt%.
The first absorbent is 20 wt% sodium hydroxide solution water solution; the second absorbent is triethylenetetramine.
In the step (7), the heat required by the mineralization reaction temperature is provided by carbon dioxide mixed gas; in the step (7), the water vapor required by the mineralization reaction humidity is provided by the water vapor in the carbon dioxide mixed gas; the water-cement ratio of the solid waste stirred and mixed in the step (7) is 0.15.
Comparative example 1
The embodiment of this comparative example is the same as example 1 except that: the ceramic membrane raw materials of the desulfurization and denitrification device are titanium oxide and modified titanium oxide, and the mass ratio is 9: 1.
Comparative example 2
The embodiment of this comparative example is the same as example 1 except that: the ceramic membrane raw material of the carbon trapping device is alumina and modified alumina, and the mass ratio is 9: 1.
Evaluation of Performance
1. Hydrophilicity of a ceramic membrane: samples of 2cm × 2cm were prepared for the ceramic membrane of the desulfurization and denitrification apparatus and the ceramic membrane of the carbon capture apparatus prepared in each example, and the hydrophilicity and hydrophobicity of the ceramic membrane were measured by the sitting drop method, and the results were the water contact angle, the content of the measured water drop was 2.5 μ l, the measurement time was 20 seconds of dropping, 5 samples were measured for the comparative example of each example, and the average value of the measured values was shown in table 1.
2. Mineralization efficiency: the process for capturing and utilizing carbon dioxide and comprehensively utilizing energy provided by each example is tested for the mineralization efficiency of the blast furnace flue gas of the same batch of steel plants, each example is tested for 5 times, and the average value of the measured values is recorded in a table 1;
wherein,
c represents the amount of carbon dioxide absorbed in the mineralized sample, c
0Representing the amount of carbon dioxide absorbed in the non-carbonized sample, c
maxThe maximum absorption of carbon dioxide calculated theoretically.
TABLE 1
The embodiment 1, the comparative examples 1 and 2 and the table 1 show that the process for capturing and utilizing carbon dioxide and comprehensively utilizing energy and the application thereof have good carbon capturing efficiency and comprehensive energy utilization efficiency, completely realize external 0 heat support, completely utilize flue gas energy, are suitable for popularization in the field of environment-friendly processes, and have wide development prospects. Wherein, the example 1 obtains the best performance index under the factors of the best preparation raw material proportion, trapping process and the like.