JP2023084058A - Method for separating carbon from carbon dioxide or carbon monoxide using nonferrous metal - Google Patents

Abstract

To solve the problems that 1. a separation device for metal oxides and powder carbon is required, but the selection of a system utilizing centrifugal force is desirable in [claim 1] and [claim 2] and that 2. the confirmation that powdery metal oxides and powdery carbon produced in reaction with carbon dioxide dissolved in respective solutions of [claims 3 to 5] can be accompanied outside of a furnace together with a gas after reaction to the outside of a reaction container is incomplete.SOLUTION: 1. With respect to [claims 1 to 2], the installation of a carbon separation recovery device is required. 2. With respect to [claims 3 to 5], it is considered that the selection of a bottom-blown furnace or a top-blown furnace having reaction efficiency and reduced in troubles for the separation recovery of reaction products is suitable. 3. As the point of controls in reactions of the claims, the monitoring of reaction systems and the controls of air feed ratio and amount using carbon monoxide gas analysis technique or device are made possible, and the same is particularly important for preventing the generation of carbon monoxide or the like.SELECTED DRAWING: Figure 31

Description

Applied technology in the field of thermodynamics in metallurgical reactions

The background of the invention is that highly concentrated carbon dioxide can be obtained by the existence of zinc oxide production technology and progress in the technology for recovering carbon dioxide.

nothing special

Yutaka Kawaoka: Journal of the Rubber Society of Japan, 26-3, 147-159, (Showa 28) Sugiro Otani: Carbon, 215, 221-224 (2004)

In recent years, there have been many reports on techniques for recovering carbon dioxide gas, and the purity of the carbon dioxide gas to be recovered has been increased.
As one of the methods for reducing carbon dioxide gas, national experiments such as underground burial are underway, and further measures to prevent global warming are required.

1. In the method of recovering zinc oxide (zinc white) and carbon from carbon dioxide using zinc vapor and oxygen-containing gas, the production of carbon monoxide (CO gas) is suppressed by supplying an oxygen-containing gas such as air. It becomes possible to react with carbon dioxide gas, and zinc oxide (zinc white) and powdery carbon are produced.
2. In the method of recovering magnesium oxide and carbon from carbon dioxide using magnesium vapor and an oxygen-containing gas, the oxygen-containing gas such as air is supplied to suppress the production of carbon monoxide and the reaction with the carbon dioxide is accelerated. It is possible to produce magnesium oxide (powdered) and powdered carbon.
3. By supplying oxygen-containing gas such as carbon dioxide gas and air to molten zinc, molten magnesium and molten aluminum, zinc oxide, magnesium oxide, alumina and carbon are produced and recovered while suppressing the production of carbon monoxide.
4. Zinc oxide and magnesium oxide and carbon are produced and recovered from carbon monoxide using zinc vapor and magnesium vapor, respectively.

1. By supplying oxygen-containing gas such as carbon dioxide gas and air, zinc vapor, magnesium vapor, and zinc solution, magnesium solution, and aluminum solution can be reacted to recover metal oxides and carbon, thus preventing global warming. It is also effective as a raw material, and it is possible to sell the economical reaction product.
2. By supplying oxygen-containing gas such as carbon monoxide and air, it reacts with zinc vapor and magnesium vapor, decomposes carbon monoxide, and recovers respective metal oxides and carbon. This also helps prevent global warming.

Reaction data between zinc vapor and carbon dioxide during oxygen enrichment Reaction data between zinc vapor and carbon dioxide when oxygen enrichment ratio is changed Reaction data of zinc vapor and carbon dioxide gas Reaction data of carbon monoxide generation in the reaction of zinc vapor and carbon dioxide gas Reaction data during the formation of carbon monoxide and carbon in the reaction between zinc vapor and carbon dioxide gas Zinc vapor pressure table (temperature and standard atmospheric pressure) Calculation example of heat balance in the reaction of vaporized zinc and carbon dioxide during oxygen enrichment at 1,000°C Reaction data between magnesium vapor and carbon dioxide during oxygen enrichment Reaction data between magnesium vapor and carbon dioxide when the oxygen enrichment ratio is increased Reaction data between magnesium vapor and carbon dioxide Reaction data of carbon monoxide generation in the reaction of magnesium vapor and carbon dioxide gas Reaction data between zinc solution and carbon dioxide during oxygen enrichment Reaction data between zinc solution and carbon dioxide gas Reaction data of carbon monoxide generation in reaction of zinc solution and carbon dioxide gas Reaction data during the formation of carbon monoxide and carbon in the reaction between zinc solution and carbon dioxide gas Reaction data between magnesium solution and carbon dioxide during oxygen enrichment Reaction data of magnesium solution and carbon dioxide gas Reaction data when carbon monoxide is generated in the reaction between magnesium solution and carbon dioxide gas Reaction data during the formation of carbon monoxide and carbon in the reaction between magnesium solution and carbon dioxide gas Reaction data between aluminum solution and carbon dioxide during oxygen enrichment Reaction data between aluminum solution and carbon dioxide gas Reaction data during the formation of carbon monoxide and carbon in the reaction between aluminum solution and carbon dioxide gas Reaction data between aluminum solution and carbon dioxide during enrichment of oxygen containing relatively highly reactive nitrogen (18) Reaction data with aluminum solution by accompanying nitrogen when oxygen is supplied as air in reaction with aluminum solution (reaction data when all moles of accompanying nitrogen react with aluminum solution) Reaction data of zinc vapor and carbon monoxide Reaction data between zinc vapor and carbon monoxide during oxygen enrichment Reaction data of zinc vapor and carbon monoxide with different oxygen enrichment ratios Reaction Data of Magnesium Vapor and Carbon Monoxide Reaction data between magnesium vapor and carbon monoxide during oxygen enrichment Reaction data between magnesium vapor and carbon monoxide with different oxygen enrichment ratios Schematic diagram of a bottom-blown furnace that can be considered as a reaction vessel for zinc solution, magnesium solution, aluminum solution, and carbon dioxide gas during oxygen enrichment.

1) The zinc vapor pressure table was calculated with reference to AIST: Network Database. Thermodynamics and fluids"; Table 1 Low-pressure specific heat Cp and Yoshio Waseda, Takahiko Okura, Yoshiaki Mori, Toru Okabe, Tetsuya Uda: Refer to Akira Yazawa's Thermodynamics Problems With the support of Smelting Process Engineering Laboratory, Department of Resource Development and Environmental Studies, Graduate School (HSC Chemistry 5.11 calculation)

1. granting the right to use the invention for a fee or selling the right to use the invention;

Although there are no working examples, there are expectations for the application of zinc white production technology from zinc vapor in a zinc distillation electric heating furnace.

It is possible to secure profits by commercializing reaction products.
Earnings from carbon dioxide treatment costs are expected. (currently undecided)

Claims (7)

A method for separating and recovering carbon and recovering zinc oxide (zinc white) by reacting zinc vapor with oxygen or carbon dioxide gas using oxygen-containing gas;
The most dominant reaction is described in equation (1).
Zn(g)+1/ _4CO2 (g)+1/ _4O2 (g)=ZnO+1/4C (1)
It is a reaction in which zinc vapor and oxygen or an oxygen-containing gas are supplied at a reaction temperature of 800° C. to 1000° C. and reacted with carbon dioxide gas to recover carbon (powder carbon; C) and zinc oxide; ZnO). This reaction is exothermic.
Reaction data are shown in FIG.
In addition to the above reactions, reactions in which carbon monoxide is the product are also described, in addition to carbon as the product.
Other reaction formulas and reaction data for comparing the reaction superiority of formula (1) are shown below.
First, in a reaction similar to the equation (1), the reaction between zinc vapor and carbon dioxide when the oxygen enrichment ratio is changed is shown in the equation (2).
Zn(g)+1/ _3CO2 (g)+1/ _6O2 (g)=ZnO+1/3C (2)
This reaction data is shown in FIG.
Equation (3) shows the reaction when oxygen is not supplied.
Zn(g)+1/ _2CO2 (g)=ZnO+1/2C (3)
This reaction data is shown in FIG.
Formula (3) is a general reaction formula when oxygen is not supplied to formula (1).
Next, the reaction with generation of carbon monoxide is shown in the formula (4).
Zn(g)+ _CO2 (g)=ZnO+CO(g) (4)
This reaction data is shown in FIG.
In the reaction of formula (4), zinc vapor and carbon dioxide gas react in a reaction region near or above the volatilization temperature of zinc to produce zinc oxide (zinc white) and carbon monoxide.
Comparing the reaction data of equations (3) and (4), the Log (K) value of the reaction equilibrium constant K at 800 ° C. or higher is larger in equation (4), so the carbon monoxide generation type reaction is in equilibrium. Therefore, it is difficult to recover zinc oxide and carbon in the reaction of formula (3).
In addition, the following formula (5) shows the reaction in which carbon monoxide and carbon are produced in addition to zinc oxide.

This reaction data is shown in FIG.
Reaction (5) is a reaction when the rate of supply of carbon dioxide gas is larger than that of equation (1) and the amount of oxygen supply is small. Compare the reaction data of equations (1), (2), and (5). Then, the following conclusions are obtained.
Comparing the reaction data of formula (2) and formula (5), the reaction of formula (2) is superior from the comparison of the Log (K) value of the reaction equilibrium constant K of formula (2), but at 950 ° C. Considering this, it seems that carbon monoxide can exist in the exhaust gas after the reaction at a relatively high concentration relative to the supplied carbon dioxide gas.
Comparing the reaction data when the ratio of oxygen used to carbon dioxide gas is increased as in formula (1) and the reaction data of formula (5) at 950 ° C, the reaction equilibrium constant K value of formula (1) is (5) It can be seen that it is nearly 100 times larger than the value of the formula K value.
In this way, oxygen was added as a condition for maintaining the amount of carbon monoxide produced in a lower state, and an efficient carbon dioxide gas decomposition process was established by zinc vapor.
It was found that the reaction equilibrium constant K value can be increased by supplying oxygen as shown in the reaction of formula (1) or by further increasing the supply rate.
Regarding the reaction temperature, since the vapor pressure of zinc is also low at temperatures lower than the boiling point, it is clear that the formation rate of zinc white and carbon decreases. temperature and standard atmospheric pressure) are shown in FIG.
Considering that the temperature at which the vapor pressure of zinc becomes relatively high is desirable for the reaction, the claimed temperature range is defined as "800°C to 1,000°C".
(1) Supplying an oxygen-containing gas (including air, etc.) as shown in the formula (hereinafter referred to as oxygen enrichment) to suppress the production of carbon monoxide is the separation of carbon dioxide from carbon dioxide. This is the most important point to increase the recovery efficiency.
Next, the heat balance of formula (1) will be described.
Using the number of reaction moles in formula (1), the reaction was carried out at 1,000°C.
FIG. 7 shows a calculation example of the heat balance including reaction heat Δ−80.6 Kcal/mol, sensible heat, and the like. This heat balance allows a stable reaction to be maintained even when oxygen is supplied by air.
When air is used as the oxygen supply gas, nitrogen N ₂ (g) is included, but no nitrogen oxides are generated in the reaction of zinc vapor and carbon dioxide gas, which is the main purpose, and it is possible to maintain a stable reaction without problems. is.
Although not described in detail, NO(g) or NO ₂ (g) can be used as an oxidizing agent in place of oxygen.
The claimed temperature range is from 900°C to 975°C. A method for separating and recovering carbon from carbon dioxide and recovering magnesium oxide using magnesium vapor;
It can be seen that it is possible to select magnesium as a non-ferrous metal element that can utilize carbon dioxide gas other than Zn.
Equation (6) shows the reaction between magnesium vapor and carbon dioxide during oxygen enrichment.
Mg(g)+1/ _3CO2 (g)+1/ _6O2 (g)=MgO+1/3C (6)
Reaction data are shown in FIG.
Also, the reaction between magnesium vapor and carbon dioxide when the oxygen enrichment ratio is increased is shown in equation (7).
Mg(g)+1/ _4CO2 (g)+1/ _4O2 (g)=MgO+1/4C (7)
Reaction data are shown in FIG.
The reaction between magnesium vapor and carbon dioxide is shown in equation (8).
Mg(g)+1/ _2CO2 (g)=MgO+1/2C (8)
Reaction data are shown in FIG.
In the reaction between magnesium vapor and carbon dioxide gas, Mg(g)+CO ₂ (g)=MgO+CO(g) (9) where the reaction at the time of carbon monoxide generation is represented by the formula (9)
Reaction data are shown in FIG.
Comparing the Log(K) values of the reaction constants in the reactions of formulas (8) and (9), the reaction in which carbon monoxide is produced is recognized to be dominant because the value of formula (9) is large.
The Log (K) values of the reaction constants in equations (6) and (7) are large values compared to the values in equation (9), in which carbon monoxide is generated. judged to be superior.
Further, it is desirable to continue the reaction at the boiling point of magnesium in the range of about 1,091°C to 1,110°C for the decomposition of carbon dioxide by the reaction during oxygen enrichment in the formulas (6) and (7). However, it is possible to suppress the production of carbon monoxide up to about 1,200° C. in the reaction in which the oxygen enrichment ratio is increased as shown in the formula (7).
If there is no special reason such as increased production of MgO, continuing the reaction in the range up to about 1,110° C. is effective in preventing a decrease in the number of carbon dioxide gas decompositions.
The claimed temperature range is 1,070° C. to 1,200° C., also considering the formula for increasing the oxygen enrichment rate. A method for separating and recovering carbon and recovering zinc oxide by reaction with carbon dioxide gas during oxygen enrichment using a zinc solution;
Equation (10) shows the reaction of the zinc solution and carbon dioxide during oxygen enrichment.
Zn+1/ _3CO2 (g)+1/ _6O2 (g)=ZnO+1/3C (10)
Reaction data are shown in FIG.
The reaction between zinc solution and carbon dioxide gas is shown in formula (11).
Zn+1/ _2CO2 (g)=ZnO+1/2C (11)
Reaction data are shown in FIG.
Equation (12) shows the reaction when carbon monoxide is generated in the reaction between the zinc solution and carbon dioxide gas.
Zn+CO ₂ (g)=ZnO+CO (g) (12)
Reaction data are shown in FIG.
In the reaction between the zinc solution and carbon dioxide gas, the reaction during the generation of carbon monoxide and carbon is shown in equation (13).
Zn+2/3CO2( _g )=ZnO+1/3CO(g)+1/3C (13)
Reaction data are shown in FIG.
Comparing the reaction data of formula (10) with the reaction data of formulas (11), (12), and (13), the Log (K) value of the reaction equilibrium constant K of formula (10) is expressed by formula (11), It can be seen that the value is considerably larger than the Log(K) value of each of the formulas (12) and (13).
The reaction of formula (10) can be carried out in a temperature range from the melting temperature of zinc of 420° C. to before reaching the boiling point while suppressing the generation of carbon monoxide.
The claimed temperature range is defined as the melting temperature range of 420°C to 850°C, where the vapor pressure of zinc is low. A method for separating and recovering carbon and recovering magnesium oxide by reaction with carbon dioxide gas during oxygen enrichment using a magnesium solution;
Equation (14) shows the reaction between the magnesium solution and carbon dioxide during oxygen enrichment.
Mg+1/ _3CO2 +1/ _6O2 (g)=MgO+1/3C (14)
Reaction data are shown in FIG.
The reaction between magnesium solution and carbon dioxide is shown in equation (15).
Mg+1/ _2CO2 (g)=MgO+1/2C (15)
Reaction data are shown in FIG. (Mg melting point: 650°C, boiling point: 1091°C)
Comparing the reaction data of the reaction formulas (14) and (15), it can be seen that the reaction between the magnesium solution of the formula (14) and the carbon dioxide gas during oxygen enrichment is significantly superior.
Furthermore, equation (16) when carbon monoxide is produced and reaction when carbon monoxide and carbon are produced are shown in equation (17).
Mg+CO ₂ (g)=MgO+CO (g) (16)
Mg+ ₂ /3CO2(g)=MgO+1/3CO(g)+1/3C (17)
The Log(K) value of the reaction equilibrium constant K of the reaction formula (14) at the time of magnesium solution and oxygen enrichment shown in FIG. 19 is larger than the values of the formulas (15) and (16). It can be seen that if the oxygen-enriched reaction of formula (14) is carried out, the reaction can be carried out while suppressing the generation of carbon monoxide within the range of about 650° C. or higher to about 1,050° C. for solution formation.
The claimed temperature range for the production and recovery of magnesium oxide and carbon is from the melting temperature of 650°C to about 1,050°C. A method for separating and recovering carbon and recovering aluminum oxide by reaction with carbon dioxide gas during oxygen enrichment using an aluminum solution;
The production and recovery of aluminum oxide and carbon in the reaction between the aluminum solution and the oxygen-enriched carbon dioxide gas is the production of carbon monoxide and the production of nitrogen compounds in the melting range of 660.3°C or higher, which is the melting temperature of aluminum. It is possible to recover the aluminum oxide powder and the carbon powder while suppressing the amount.
The reaction is shown in formula (18).

Reaction data are shown in FIG.
The reaction between aluminum solution and carbon dioxide gas is shown in equation (19).
Al+3/4CO2 ( _g )=1/ _2Al2O3 + ₃ /4C (19)
Reaction data are shown in FIG.
Equation (20) shows the reaction during the production of carbon monoxide and carbon in the reaction between the aluminum solution and carbon dioxide gas.
Al+ _CO2 (g)=1/ _2Al2O3 +1/2CO(g)+ ₁ /2C (20)
Reaction data are shown in FIG.
Eq. (21) shows the reaction between the aluminum solution and accompanying nitrogen when the oxygen enrichment reaction of Eq. (18) is carried out in air.

Reaction data are shown in FIG.
(18) Calculate the number of moles of accompanying nitrogen when air is used to supply oxygen in the equation, and assume that the entire amount directly reacts with aluminum. confirm.
The Log(K) value of the equilibrium constant K of the reaction formula was calculated on the assumption that all of the accompanying nitrogen reacted, and was compared with the value of Log(K) in the formula (18).
Accompanying nitrogen is (5/12*878/21)=65/63 moles and this quantity is shown in equation (22) for reaction with aluminum solution.
130/63Al+65/63N ₂ (g)=130/63AlN (22)
Reaction data are shown in FIG.
Even if it is assumed that the accompanying nitrogen reacts directly with aluminum, the value of Log (K) of the reaction data for recovering alumina and carbon by the reaction with carbon dioxide gas during oxygen enrichment shown in equation (18) is 680 ° C. Since it is the highest in the range of 980° C., it is confirmed by the formula (18) that stable oxide recovery is possible.
The claimed temperature range is from 680°C to 980°C. A method for separating and recovering carbon and recovering zinc oxide (zinc white) by reaction of zinc vapor with carbon monoxide during oxygen enrichment (including oxygen supply by air);
Equation (23) shows the reaction between zinc vapor and carbon monoxide.
Zn(g)+CO(g)=ZnO+C (23)
Reaction data are shown in FIG.
This reaction is a reaction that forms a small amount of reaction product per unit time and does not fall under the claims.
Equation (24) shows the reaction between zinc vapor and carbon monoxide during oxygen enrichment.
Zn(g)+1/3CO(g)+1/ _3O2 (g)=ZnO+1/3C (24)
Reaction data are shown in FIG.
Furthermore, reaction of zinc vapor with carbon monoxide with different oxygen enrichment ratios is shown in (25).
Zn(g)+1/2CO(g)+1/ _O2 (g)=ZnO+1/2C (25)
Reaction data are shown in FIG.
Comparing the reaction data of equations (24) and (25), there is no problem with the reaction equilibrium constant K value, etc., although there are differences in the carbon monoxide and oxygen enrichment ratios and the amount of carbon produced. It is claimed to be produced by the reactions of formulas (24) and (25).
The claimed temperature range is from 900°C to 975°C. A method for separation and recovery of carbon and recovery of magnesium oxides by reaction of magnesium vapor with carbon monoxide during oxygen enrichment (including oxygen supply by air);
The reaction between magnesium vapor and carbon monoxide is shown in equation (26).
Zn(g)+CO(g)=MnO+C (26)
Reaction data are shown in FIG.
In this reaction, air may be used for cooling after the reaction, but carbon can be separated and recovered from carbon monoxide.
The reaction between magnesium vapor and carbon monoxide during oxygen enrichment is shown in Equation 27.
Mg (g) + 1/3CO (g) + 1/ _3O2 (g) = ZnO + 1/3C (27)
Reaction data are shown in FIG.
Further, reactions of magnesium vapor with carbon monoxide with different oxygen enrichment ratios are shown in (28).
Mg (g) + 1/2 (g) + 1/ _O2 (g) = MgO + 1/2C (28)
Reaction data are shown in FIG.
Comparing the reaction data of formulas (27) and (28), there is no problem with the reaction equilibrium constant K value, etc., although there are differences in the carbon monoxide and oxygen enrichment ratios and the amount of carbon produced. It is claimed to be produced by the reactions of formulas (27) and (25).
The claimed temperature range is from 1,070°C to 1,200°C.

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