CN115738599B - At the same time absorb NOxPreparation method of complexing denitration liquid of CO - Google Patents

Abstract

The invention discloses a preparation method of complex denitration liquid capable of simultaneously absorbing NO _x and CO, which comprises the following steps: the method comprises the following steps: mixing and dissolving triethylene diamine, cuprous chloride and magnesium chloride at a first temperature, and continuously stirring at a first preset stirring speed for a first preset time at the first temperature under the nitrogen atmosphere after all solids are dissolved to obtain a first mixed solution; mixing and dissolving disodium ethylenediamine tetraacetate, cysteine, piperazine and ferrous sulfate at a second temperature, and continuously stirring at a second preset stirring speed for a second preset time at a second temperature under nitrogen atmosphere after all solids are dissolved to obtain a second mixed solution; mixing the first mixed solution and the first mixed solution according to a preset volume ratio, and then adding an acidic substance or an alkaline substance to adjust the pH of the mixed solution to obtain the complex denitration solution. Is favorable for solving the problems of quick failure of the complex denitration liquid, low absorption capacity and regeneration cost of the complex denitration liquid.

Description

Preparation method of complex denitrification liquid capable of absorbing NOx and CO simultaneously

Technical Field

The invention relates to the technical field of flue gas denitration, and in particular to a method for preparing a complex denitration liquid capable of absorbing _NOx and CO simultaneously.

Background technique

In addition to the power industry, steel, cement, metallurgy, coking, coal chemical industry, industrial boilers and industrial kilns are also areas with large coal consumption, and the sintering flue gas they produce also contains a large amount of nitrogen oxides (NO _x ).

At present, low-temperature wet denitration of nitrogen oxides (NO _x ) contained in industrial sintering flue gas is generally carried out by using ethylenediaminetetraacetic acid (EDTA) complexed ferrous (Fe(II)EDTA) denitration liquid, which can be well grafted with wet desulfurization equipment to ultimately achieve standard emission of SO ₂ and NO _x in sintering flue gas. However, during the denitration process, O ₂ in the flue gas will oxidize Fe ²⁺ in the Fe(II)EDTA complex denitration liquid into Fe ³⁺ , and the addition of EDTA chelating agent will also accelerate the oxidation reaction. Fe(III)EDTA formed after the oxidation of Fe(II)EDTA has no affinity for NO, resulting in the disadvantages of easy oxidation, rapid failure and precipitation of the complex denitration liquid, which seriously restricts the engineering application of complex denitration.

Chen Shuo and others used a self-made spray tower to conduct wet simultaneous desulfurization and denitrification experiments. Based on ethylenediaminetetraacetic acid (EDTA) complexed ferrous absorption liquid and cysteine complexed ferrous absorption liquid, a composite absorption liquid was developed. The experimental results show that for a single complex absorption liquid, the EDTA complexed ferrous absorption liquid has a better denitrification effect, which can maintain a NO removal rate of more than 60% within 70 minutes, while the cysteine complexed ferrous absorption liquid can maintain a good desulfurization effect for a long time, and can maintain a _SO2 removal rate of more than 90% within 180 minutes; the desulfurization and denitrification performance of the composite absorption liquid is significantly improved compared with the single complex absorption liquid. Under the optimized conditions of complex concentration of 0.05 mol/L, absorption liquid pH of 8, EDTA to cysteine molar ratio of 1:2, and Fe2 ⁺ concentration of 0.075 mol/L, the NO removal rate within 90 minutes is basically maintained at more than 70%, and the _SO2 removal rate basically reaches 100%. Through improvements, the denitrification performance of the composite absorption liquid has been improved, but the problems of low absorption capacity and rapid failure of the denitrification liquid have not been completely solved (Chemical and Environmental Protection, Vol. 37, No. 3, 2017).

However, in addition to a large amount of nitrogen oxides ( _NOx ) in sintering flue gas, industrial sintering flue gas also contains a large amount of reducing gas CO. For example, sintering flue gas contains 0.5%-1% CO. If the complexing liquid can absorb CO in the flue gas while absorbing _NOx , and regenerate the ineffective complexing denitrification liquid by using the reducing property of CO in the liquid phase, it will greatly reduce the regeneration cost of complexing denitrification, which is conducive to promoting the engineering application of complexing denitrification. However, there is no relevant research on the preparation of complexing liquid for absorbing _NOx and CO at the same time.

Summary of the invention

In order to solve the above technical problems, the present invention proposes a method for preparing a complex denitrification liquid that absorbs _NOx and CO simultaneously, which can solve the technical problems of the prior art such as fast failure of the complex denitrification liquid, low absorption capacity and high regeneration cost of the failed complex denitrification liquid.

The embodiment of the present invention discloses a method for preparing a complex denitration liquid for absorbing NOx and CO simultaneously, comprising the following steps:

Mixing and dissolving triethylenediamine, cuprous chloride, and magnesium chloride at a first temperature, and after all the solids are dissolved, continuously stirring at a first predetermined stirring speed at the first temperature for a first predetermined time under a nitrogen atmosphere to obtain a first mixed solution;

Disodium ethylenediaminetetraacetate, cysteine, piperazine, and ferrous sulfate are mixed and dissolved at a second temperature, and after all the solids are dissolved, stirring is continued at a second predetermined stirring speed at the second temperature for a second predetermined time under a nitrogen atmosphere to obtain a second mixed solution;

The first mixed solution and the second mixed solution are mixed according to a predetermined volume ratio, and then an acidic substance or an alkaline substance is added to adjust the pH of the mixed solution to obtain the complex denitration solution.

According to one embodiment of the present invention, the first temperature is 30-50° C., the first stirring speed is 200-300 rpm, and the first predetermined time is 240-300 min.

According to one embodiment of the present invention, the concentration of triethylenediamine in the first mixed solution is 4.0-5.0 mol/L, the concentration of cuprous chloride is 2.5-3.5 mol/L, the concentration of magnesium chloride is 3.0-4.0 mol/L, and the molar ratio of cuprous chloride to magnesium chloride is (8-9):10.

According to an embodiment of the present invention, the second temperature is 20-40° C., the second predetermined stirring speed is 200-300 rpm, and the second predetermined time is 10-20 min.

According to one embodiment of the present invention, the concentration of disodium ethylenediaminetetraacetate in the second mixed solution is 0.075-0.1 mol/L, the concentration of cysteine is 0.025-0.05 mol/L, the concentration of piperazine is 0.5-1.0 mol/L, the concentration of ferrous sulfate is 0.05-0.075 mol/L, and the molar ratio of the disodium ethylenediaminetetraacetate, the cysteine, and the ferrous sulfate is 15:5:10.

According to one embodiment of the present invention, the predetermined volume ratio is 1:(35-70), and the pH of the mixed solution is 6.0-7.0.

By adopting the above technical solution, the present invention has at least the following beneficial effects:

The invention provides a method for preparing a complex denitration liquid capable of absorbing _NOx and CO at the same time. The method comprises the following steps: preparing a CO absorbent using triethylenediamine, cuprous chloride and magnesium chloride and preparing a _NOx absorbent using disodium ethylenediaminetetraacetate, cysteine, piperazine and ferrous sulfate, mixing the two absorbents according to a certain volume ratio, and then adjusting the pH value of the mixed solution to obtain a complex denitration liquid capable of absorbing _NOx and CO at the same time. The method is beneficial for subsequently regenerating the failed complex denitration liquid using the reducing property of CO, and is beneficial for solving the problems of fast failure of the complex denitration liquid, low absorption capacity and regeneration cost of the complex denitration liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of a method for preparing a complex denitration liquid for absorbing NO _x and CO simultaneously disclosed in one embodiment of the present invention;

FIG2 is a curve diagram showing the removal rate of NO and CO by the complex denitration liquid prepared in Example 1 of the present invention;

FIG3 is a curve diagram showing the removal rate of NO and CO by the complex denitration liquid prepared in Example 2 of the present invention;

FIG4 is a curve diagram showing the removal rate of NO and CO by the complex denitration liquid prepared in Example 3 of the present invention;

FIG5 is a curve diagram showing the removal rate of NO and CO by the complex denitration liquid prepared in Example 4 of the present invention;

FIG6 is a curve diagram showing the removal rate of NO and CO by the complex denitration liquid prepared in Example 5 of the present invention;

FIG7 is a curve diagram showing the removal rate of NO and CO by the complex denitration liquid prepared in Example 6 of the present invention;

FIG8 is a curve diagram showing the removal rates of NO and CO by the complex denitration liquid prepared in Example 7 of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

As shown in FIG1 , an embodiment of the present invention discloses a method for preparing a complex denitration liquid for absorbing NO _x and CO simultaneously, comprising the following steps:

Mixing and dissolving triethylenediamine, cuprous chloride and magnesium chloride at a first temperature, and after all the solids are dissolved, continuously stirring at a first predetermined stirring speed at the first temperature for a first predetermined time under a nitrogen atmosphere to obtain a first mixed solution;

Disodium ethylenediaminetetraacetate, cysteine, piperazine, and ferrous sulfate are mixed and dissolved at a second temperature, and after all the solids are dissolved, stirring is continued at a second predetermined stirring speed at the second temperature for a second predetermined time under a nitrogen atmosphere to obtain a second mixed solution;

The first mixed solution and the second mixed solution are mixed according to a predetermined volume ratio, and then an acidic substance or an alkaline substance is added to adjust the pH of the mixed solution to obtain a complex denitrification solution.

In some embodiments, the first temperature is 30-50° C., the first stirring speed is 200-300 rpm, and the first predetermined time is 240-300 min.

In some embodiments, the concentration of triethylenediamine in the first mixed solution is 4.0-5.0 mol/L, the concentration of cuprous chloride is 2.5-3.5 mol/L, the concentration of magnesium chloride is 3.0-4.0 mol/L, and the molar ratio of cuprous chloride to magnesium chloride is (8-9):10.

In some embodiments, the second temperature is 20-40° C., the second predetermined stirring speed is 200-300 rpm, and the second predetermined time is 10-20 min.

In some embodiments, the concentration of disodium ethylenediaminetetraacetate in the second mixed solution is 0.075-0.1 mol/L, the concentration of cysteine is 0.025-0.05 mol/L, the concentration of piperazine is 0.5-1.0 mol/L, the concentration of ferrous sulfate is 0.05-0.075 mol/L, and the molar ratio of disodium ethylenediaminetetraacetate, cysteine, and ferrous sulfate is 15:5:10.

In some embodiments, the predetermined volume ratio is 1:(35-70), and the pH of the mixed solution is 6.0-7.0.

The present invention will be described in detail below through examples, but the protection scope of the present invention is not limited thereto.

Example 1

Take 100.80g of triethylenediamine (converted to a concentration of 4.5mol/L in the solution, the same below), 49.50g of cuprous chloride (2.5mol/L) and 126.88g of magnesium chloride hexahydrate (3.125mol/L) and put them into a beaker, the molar ratio of cuprous chloride to magnesium chloride is 8:10, add 150ml of distilled water, stir and dissolve at 40℃, after all the solids are dissolved, adjust the volume to 200ml, maintain the temperature at 40℃ and stir continuously for 240min under a nitrogen atmosphere, and the stirring speed is 200rpm.

After the above steps are completed, the pH of the solution is adjusted to 6.5 with acid (sulfuric acid, hydrochloric acid, etc.), 3 ml is taken and mixed with 197 ml of distilled water, and poured into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas flow rate 2L/min, _O2 concentration 16%, NO concentration 500mg/ ^m3 , CO concentration 5000mg/ ^m3 , gas-liquid reaction conditions are: temperature 40℃, total time 60min, NO and CO concentrations in the flue gas after the reaction are detected every 10min, and the corresponding removal rate is calculated. The change of removal rate is shown in Figure 2.

As shown in Figure 2, the CO absorbent prepared by triethylenediamine, cuprous chloride and magnesium chloride has a removal effect on CO, but has almost no removal effect on NO.

Example 2

Take 5.58g of disodium ethylenediaminetetraacetate (0.075mol/L), 0.61g of cysteine (0.025mol/L), 8.60g of piperazine (0.5mol/L) and 2.78g of ferrous sulfate heptahydrate (0.05mol/L) and put them into a beaker. The molar ratio of disodium ethylenediaminetetraacetate, cysteine and ferrous sulfate is 15:5:10. Add 150ml of distilled water and stir to dissolve at 30℃. After all the solids are dissolved, adjust the volume to 200ml. Under a nitrogen atmosphere, maintain the temperature at 30℃ and stir continuously for 10min at a stirring speed of 200rpm.

After the above steps are completed, the pH of the solution is adjusted to 6.5 with alkali (sodium hydroxide, etc.), and poured into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas flow rate 2L/min, _O2 concentration 16%, NO concentration 500mg/ ^m3 , CO concentration 5000mg/ ^m3 , gas-liquid reaction conditions are: temperature 40℃, total time 60min, NO and CO concentrations in the flue gas after the reaction are detected every 10min, and the corresponding removal rate is calculated. The change of the removal rate is shown in Figure 3.

As shown in FIG3 , the NO _x absorbent prepared by disodium ethylenediaminetetraacetate, cysteine, piperazine and ferrous sulfate has a removal effect on NO but almost no removal effect on CO.

Example 3

Step 1: Take 100.80g triethylenediamine (4.5mol/L), 49.50g cuprous chloride (2.5mol/L) and 126.88g magnesium chloride hexahydrate (3.125mol/L) and put them into a beaker, the molar ratio of cuprous chloride to magnesium chloride is 8:10, add 150ml distilled water, stir and dissolve at 40℃, after all the solids are dissolved, adjust the volume to 200ml, maintain the temperature at 40℃ and stir continuously for 240min under nitrogen atmosphere, and the stirring speed is 200rpm.

Step 2: Take 5.58g of disodium ethylenediaminetetraacetate (0.075mol/L), 0.61g of cysteine (0.025mol/L), 8.60g of piperazine (0.5mol/L) and 2.78g of ferrous sulfate heptahydrate (0.05mol/L) and put them into a beaker. The molar ratio of disodium ethylenediaminetetraacetate, cysteine and ferrous sulfate is 15:5:10. Add 150ml of distilled water and stir to dissolve at 30°C. After all the solids are dissolved, adjust the volume to 200ml. Under a nitrogen atmosphere, maintain the temperature at 30°C and stir continuously for 10min at a stirring speed of 200rpm.

Take 3 ml of the liquid in step 1 and 197 ml of the liquid in step 2 and mix them. The volume ratio of the two is 1:65.7. Use acid (sulfuric acid, hydrochloric acid, etc.) to adjust the pH of the mixed complex liquid to 6.5, and pour it into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas flow rate 2L/min, _O2 concentration 16%, NO concentration 500mg/ ^m3 , CO concentration 5000mg/ ^m3 , gas-liquid reaction conditions are: temperature 40℃, total time 60min, NO and CO concentrations in the flue gas after the reaction are detected every 10min, and the corresponding removal rate is calculated. The change of removal rate is shown in Figure 4.

In this embodiment 3, the CO absorbent configured in embodiment 1 and the _NOx absorbent configured in embodiment 2 are mixed in a certain volume ratio to obtain a mixed absorbent. The CO removal rate and NO removal rate of the mixed absorbent are substantially the same as the CO removal rate of the CO absorbent configured alone in embodiment 1 and the NO removal rate of the _NOx absorbent configured alone in embodiment 2, respectively.

Example 4

Take 112.00g triethylenediamine (5mol/L), 69.30g cuprous chloride (3.5mol/L) and 157.89g magnesium chloride hexahydrate (3.889mol/L) and put them into a beaker, the molar ratio of cuprous chloride to magnesium chloride is 9:10, add 150ml distilled water, stir and dissolve at 40℃, after all the solids are dissolved, adjust the volume to 200ml, maintain the temperature at 40℃ and stir continuously for 240min under nitrogen atmosphere, and the stirring speed is 200rpm.

Take 5.58g of disodium ethylenediaminetetraacetate (0.075mol/L), 0.61g of cysteine (0.025mol/L), 8.60g of piperazine (0.5mol/L) and 2.78g of ferrous sulfate heptahydrate (0.05mol/L) and put them into a beaker. The molar ratio of disodium ethylenediaminetetraacetate, cysteine and ferrous sulfate is 15:5:10. Add 150ml of distilled water and stir to dissolve at 30℃. After all the solids are dissolved, adjust the volume to 200ml. Under a nitrogen atmosphere, maintain the temperature at 30℃ and stir continuously for 10min at a stirring speed of 200rpm.

Take 3 ml of the liquid in step 1 and 197 ml of the liquid in step 2 and mix them. The volume ratio of the two is 1:65.7. Use acid (sulfuric acid, hydrochloric acid, etc.) to adjust the pH of the mixed complex liquid to 6.5, and pour it into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas flow rate 2L/min, _O2 concentration 16%, NO concentration 500mg/ ^m3 , CO concentration 5000mg/ ^m3 , gas-liquid reaction conditions are: temperature 40℃, total time 60min, NO and CO concentrations in the flue gas after the reaction are detected every 10min, and the corresponding removal rate is calculated. The change of removal rate is shown in Figure 5.

As shown in FIG5 , based on Example 3, the CO absorbent formulation was optimized and adjusted, and the CO removal rate was increased by about 5 percentage points.

Example 5

Step 1: Take 112.00g triethylenediamine (5mol/L), 69.30g cuprous chloride (3.5mol/L) and 157.89g magnesium chloride hexahydrate (3.889mol/L) and put them into a beaker, the molar ratio of cuprous chloride to magnesium chloride is 9:10, add 150ml distilled water, stir and dissolve at 50℃, after all the solids are dissolved, adjust the volume to 200ml, maintain 50℃ temperature and stir continuously for 300min under nitrogen atmosphere, stirring speed is 300rpm.

Step 2: Take 5.58g of disodium ethylenediaminetetraacetate (0.075mol/L), 0.61g of cysteine (0.025mol/L), 8.60g of piperazine (0.5mol/L) and 2.78g of ferrous sulfate heptahydrate (0.05mol/L) and put them into a beaker. The molar ratio of disodium ethylenediaminetetraacetate, cysteine and ferrous sulfate is 15:5:10. Add 150ml of distilled water and stir to dissolve at 30°C. After all the solids are dissolved, adjust the volume to 200ml. Under a nitrogen atmosphere, maintain the temperature at 30°C and stir continuously for 10min at a stirring speed of 200rpm.

Take 3 ml of the liquid in step 1 and 197 ml of the liquid in step 2 and mix them. The volume ratio of the two is 1:65.7. Use acid (sulfuric acid, hydrochloric acid, etc.) to adjust the pH of the mixed complex liquid to 6.5, and pour it into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas volume 2L/min, _O2 concentration 16%, NO concentration 500mg/ ^m3 , CO concentration 5000mg/ ^m3 , gas-liquid reaction conditions are: temperature 40℃, total time 60min, detect NO and CO concentrations in the flue gas after the reaction every 10min, and calculate the corresponding removal rate. The change of removal rate is shown in Figure 6.

As shown in FIG6 , based on Example 4, the CO absorbent formulation manufacturing process parameters were optimized and adjusted, and the CO removal rate was increased by about 4 percentage points.

Example 6

Take 112.00g triethylenediamine (5mol/L), 69.30g cuprous chloride (3.5mol/L) and 157.89g magnesium chloride hexahydrate (3.889mol/L) and put them into a beaker, the molar ratio of cuprous chloride to magnesium chloride is 9:10, add 150ml distilled water, stir and dissolve at 50℃, after all the solids are dissolved, adjust the volume to 200ml, maintain 50℃ temperature and stir continuously for 300min under nitrogen atmosphere, stirring speed is 300rpm.

Take 7.44g of disodium ethylenediaminetetraacetate (0.1mol/L), 0.81g of cysteine (0.033mol/L), 11.47g of piperazine (0.75mol/L) and 3.71g of ferrous sulfate heptahydrate (0.067mol/L) and put them into a beaker. The molar ratio of disodium ethylenediaminetetraacetate, cysteine and ferrous sulfate is 15:5:10. Add 150ml of distilled water and stir to dissolve at 30℃. After all the solids are dissolved, adjust the volume to 200ml. Under a nitrogen atmosphere, maintain the temperature at 30℃ and continue stirring for 20min at a stirring speed of 300rpm.

Take 3 ml of the liquid in step 1 and 197 ml of the liquid in step 2 and mix them. The volume ratio of the two is 1:65.7. Use acid (sulfuric acid, hydrochloric acid, etc.) to adjust the pH of the mixed complex liquid to 6.5, and pour it into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas volume 2L/min, _O2 concentration 16%, NO concentration 500mg/m3, CO concentration 5000mg/m3, gas-liquid reaction conditions are: temperature 40℃, total time 60min, detect NO and CO concentrations in the flue gas after the reaction every 10min, and calculate the corresponding removal rate. The change of removal rate is shown in Figure 7.

As shown in FIG. 7 , based on Example 5, the NO absorbent formulation and manufacturing process parameters were optimized and adjusted, and the NO removal rate was increased by about 10 percentage points.

Example 7

Take 112.00g triethylenediamine (5mol/L), 69.30g cuprous chloride (3.5mol/L) and 157.89g magnesium chloride hexahydrate (3.889mol/L) and put them into a beaker, the molar ratio of cuprous chloride to magnesium chloride is 9:10, add 150ml distilled water, stir and dissolve at 50℃, after all the solids are dissolved, adjust the volume to 200ml, maintain 50℃ and stir continuously for 300min under nitrogen atmosphere, stirring speed is 300rpm.

Take 7.44g of disodium ethylenediaminetetraacetate (0.1mol/L), 0.81g of cysteine (0.033mol/L), 11.47g of piperazine (0.75mol/L) and 3.71g of ferrous sulfate heptahydrate (0.067mol/L) and put them into a beaker. The molar ratio of disodium ethylenediaminetetraacetate, cysteine and ferrous sulfate is 15:5:10. Add 150ml of distilled water and stir to dissolve at 30℃. After all the solids are dissolved, adjust the volume to 200ml. Under a nitrogen atmosphere, maintain the temperature at 30℃ and continue stirring for 20min at a stirring speed of 300rpm.

Take 4 ml of the liquid in step 1 and 196 ml of the liquid in step 2 and mix them. The volume ratio of the two is 1:49. Use acid (sulfuric acid, hydrochloric acid, etc.) to adjust the pH of the mixed complex liquid to 7, and pour it into the absorption bottle to react with the prepared flue gas. The flue gas conditions are: gas volume 2L/min, _O2 concentration 16%, NO concentration 500mg/ ^m3 , CO concentration 5000mg/ ^m3 , gas-liquid reaction conditions are: temperature 40℃, total time 60min, detect NO and CO concentrations in the flue gas after the reaction every 10min, and calculate the corresponding removal rate. The change of removal rate is shown in Figure 8.

As shown in FIG8 , based on Example 6, the CO removal rate was increased by about 10 percentage points by optimizing the ratio of CO and NO absorbents and the pH after mixing.

In summary, the embodiment of the present invention prepares a CO absorbent using triethylenediamine, cuprous chloride, and magnesium chloride, and prepares a _NOx absorbent using disodium ethylenediaminetetraacetic acid, cysteine, piperazine, and ferrous sulfate, and mixes the above two absorbents in a certain volume ratio, and then adjusts the pH of the mixed solution to obtain a complex denitration liquid that can absorb _NOx and CO at the same time, which is beneficial for the subsequent regeneration of the failed complex denitration liquid using the reducing property of CO, and is beneficial for solving the problems of fast failure of the complex denitration liquid, low absorption capacity, and regeneration cost of the complex denitration liquid.

It should be particularly pointed out that the various components or steps in the above-mentioned embodiments can be cross-linked, replaced, added, or deleted. Therefore, the combinations formed by these reasonable permutations and combinations should also fall within the scope of protection of the present invention, and the scope of protection of the present invention should not be limited to the embodiments.

The above are exemplary embodiments disclosed in the present invention. The order disclosed in the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. However, it should be noted that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope (including claims) disclosed in the embodiments of the present invention is limited to these examples. Various changes and modifications may be made without departing from the scope defined in the claims. The functions, steps and/or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims (3)

1. The preparation method of the complex denitration liquid capable of simultaneously absorbing NOx and CO is characterized by comprising the following steps of:

mixing and dissolving triethylene diamine, cuprous chloride and magnesium chloride at a first temperature, continuously stirring at a first preset stirring speed for a first preset time at the first temperature under a nitrogen atmosphere after all solids are dissolved to obtain a first mixed solution, wherein the concentration of the triethylene diamine in the first mixed solution is 4.0-5.0 mol/L, the concentration of the cuprous chloride in the first mixed solution is 2.5-3.5 mol/L, the concentration of the magnesium chloride is 3.0-4.0 mol/L, and the molar ratio of the cuprous chloride to the magnesium chloride is (8-9): 10, wherein the first temperature is 30-50 ℃;

Mixing and dissolving disodium ethylenediamine tetraacetate, cysteine, piperazine and ferrous sulfate at a second temperature, continuously stirring for a second preset time at a second preset stirring speed at the second temperature under a nitrogen atmosphere after all solids are dissolved to obtain a second mixed solution, wherein the concentration of disodium ethylenediamine tetraacetate in the second mixed solution is 0.075-0.1 mol/L, the concentration of cysteine is 0.025-0.05 mol/L, the concentration of piperazine is 0.5-1.0 mol/L, the concentration of ferrous sulfate is 0.05-0.075 mol/L, and the molar ratio of disodium ethylenediamine tetraacetate to cysteine to ferrous sulfate is 15:5:10, wherein the second temperature is 20-40 ℃;

Mixing the first mixed solution and the first mixed solution according to a preset volume ratio, and then adding an acidic substance or an alkaline substance to adjust the pH of the mixed solution to obtain the complex denitration solution, wherein the preset volume ratio is 1: (35-70), wherein the pH of the mixed solution is 6.0-7.0.

2. The method for preparing a complex denitration liquid capable of simultaneously absorbing NOx and CO according to claim 1, wherein the first stirring speed is 200 to 300rpm, and the first predetermined time is 240 to 300min.

3. The method for preparing a complex denitration liquid capable of simultaneously absorbing NOx and CO according to claim 1, wherein the second predetermined stirring speed is 200 to 300rpm, and the second predetermined time is 10 to 20 minutes.