APPARATUS AND METHOD FOR STEEL SLAG CARBON FIXATION

Abstract

An apparatus for steel slag carbon fixation includes an apparatus body. A spray thrower and a gas outlet arranged at a top of a structure of the apparatus body, a material inlet, a material outlet and a gas inlet are formed on the apparatus body. A transfer unit having a plurality of transfer mechanisms is arranged inside the apparatus body. The apparatus feeds industrial waste gas containing carbon dioxide into steel slag while maintaining environmental humidity in a range from 80% to 100% to implement steel slag carbon fixation. Water content of the steel slag is maintained by controlling the environment humidity. Time of contact between water and the steel slag is reduced, element calcium in the steel slag is prevented from being dissolved out, a water film is not formed on a surface of the steel slag, thereby facilitating deep reaction of carbon dioxide and free calcium oxide.

Claims

1. An apparatus for steel slag carbon fixation, comprising: an apparatus body, a spray thrower and a gas outlet arranged at a top of a structure of the apparatus body, and a material inlet, a material outlet and a gas inlet formed on the apparatus body, wherein: a position of the material inlet is higher than a position of the material outlet, the gas inlet is located between the material inlet and the material outlet, a transfer unit is arranged inside the apparatus body, and the transfer unit includes a plurality of transfer mechanisms.

2. A method for steel slag carbon fixation, comprising the following step: feeding industrial waste gas containing carbon dioxide into steel slag under a condition that environment humidity ranges from 80% to 100%.

3. The method for steel slag carbon fixation according to claim 2, wherein the industrial waste gas containing carbon dioxide further contains SO.sub.2, and optionally, a volume content of SO.sub.2 ranges from 100 ppm to 300 ppm.

4. The method for steel slag carbon fixation according to claim 3, wherein the environment humidity is controlled through a spray amount of spray water.

5. The method for steel slag carbon fixation according to claim 4, wherein: a feeding amount of the industrial waste gas ranges from 150,000 m.sup.3/h to 230,000 m.sup.3/h; and/or a feeding amount of steel slag ranges from 1 t/h to 1.5 t/h.

6. The method for steel slag carbon fixation according to claim 5, wherein: a volume content of CO.sub.2 in the industrial waste gas containing carbon dioxide is greater than or equal to 10%, and optionally, the volume content of CO.sub.2 is greater than or equal to 25%; and/or a temperature of the industrial waste gas ranges from 100 C. to 200 C.

7. The method for steel slag carbon fixation according to claim 6, wherein a pressure intensity ranges from 1 atm to 1.5 atm in a reaction process of the steel slag and the industrial waste gas containing carbon dioxide.

8. The method for steel slag carbon fixation according to claim 2, wherein: time of contact between the steel slag and the industrial waste gas containing carbon dioxide ranges from 0.5 h to 2 h; and/or a transfer rate of the steel slag ranges from 0.5 m/min to 1.5 m/min.

9. The method for steel slag carbon fixation according to claim 8, wherein: a particle diameter of 50% or more of the steel slag is less than or equal to 80 m; and/or before feeding, a water content of the steel slag ranges from 5% to 15%; and/or water is at least one type of industrial wastewater or reclaimed water.

10. (canceled)

11. The method for steel slag carbon fixation according to claim 3, wherein: time of contact between the steel slag and the industrial waste gas containing carbon dioxide ranges from 0.5 h to 2 h; and/or a transfer rate of the steel slag ranges from 0.5 m/min to 1.5 m/min.

12. The method for steel slag carbon fixation according to claim 4, wherein: time of contact between the steel slag and the industrial waste gas containing carbon dioxide ranges from 0.5 h to 2 h; and/or a transfer rate of the steel slag ranges from 0.5 m/min to 1.5 m/min.

13. The method for steel slag carbon fixation according to claim 5, wherein: time of contact between the steel slag and the industrial waste gas containing carbon dioxide ranges from 0.5 h to 2 h; and/or a transfer rate of the steel slag ranges from 0.5 m/min to 1.5 m/min.

14. The method for steel slag carbon fixation according to claim 6, wherein: time of contact between the steel slag and the industrial waste gas containing carbon dioxide ranges from 0.5 h to 2 h; and/or a transfer rate of the steel slag ranges from 0.5 m/min to 1.5 m/min.

15. The method for steel slag carbon fixation according to claim 7, wherein: time of contact between the steel slag and the industrial waste gas containing carbon dioxide ranges from 0.5 h to 2 h; and/or a transfer rate of the steel slag ranges from 0.5 m/min to 1.5 m/min.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly describe specific implementations of the present application or technical solutions in the prior art, the accompanying drawings needed for the description in the specific implementations or in the prior art will be briefly introduced below. Apparently, the accompanying drawings in the following description are some implementations of the present application. Those ordinarily skilled in the art can also obtain other accompanying drawings according to these accompanying drawings without making creative work.

[0023] FIG. 1 is a schematic structural diagram of an apparatus for steel slag carbon fixation in the present application.

[0024] Reference numerals in the accompanying drawings:

[0025] 1material outlet, 2gas inlet, 3material inlet, 4spray thrower, 5gas outlet, 6apparatus body, and 7transfer unit.

DETAILED DESCRIPTION

[0026] The following examples are provided for better further understanding the present application, which are not limited to the preferable implementations and do not constitute a limitation on the content and the protection scope of the present application, and any product the same as or similar to the present application obtained by anybody under the inspiration of the present application or by combining the present application with features in the other prior art falls within the protection scope of the present application.

[0027] Where specific experiment steps or conditions are not indicated in the examples can be performed according to operations of conventional experiment steps or conditions described by documents in the art. Whatever reagent or instrument used with no indicated manufacturer may be a conventional reagent product obtained through market purchase.

[0028] The present application provides an apparatus for steel slag carbon fixation, as shown in FIG. 1, the apparatus for steel slag carbon fixation includes an apparatus body 6, and a spray thrower 4 and a gas outlet 5 arranged at a top of a structure of the apparatus body 6, a material inlet 3, a material outlet 1 and a gas inlet 2 are further formed on the apparatus body 6, a position of the material inlet 3 is higher than a position of the material outlet 1, the gas inlet 2 is located between the material inlet 3 and the material outlet 1, a transfer unit 7 is arranged inside the apparatus body 6, and the transfer unit 7 includes a plurality of transfer mechanisms. In use, steel slag with a water content meeting a requirement is fed onto the transfer mechanisms through the material inlet 3, an arrangement angle of each transfer mechanism may be adjusted at will so as to guarantee that the steel slag may be spread on the transfer mechanism as thin as possible, the transfer mechanisms drive the steel slag to be transferred, in a transfer process, industrial waste gas containing carbon dioxide or containing carbon dioxide and sulfur dioxide is fed from the gas inlet 2, reclaimed water or the industrial waste gas is sprayed from the spray thrower 4, so environment humidity in the apparatus body 6 is maintained, and the steel slag of which carbon fixation is completed is delivered out via the material outlet 1.

[0029] Specifically, a feeding mode of the present application may adopt spiral feeding, transfer feeding, vibrating feeding or other modes, preferably, the vibrating feeding mode, and the steel slag can be spread on the transfer unit 7 more uniformly by maintaining a certain vibration frequency.

[0030] Specifically, a discharging mode of the present application may adopt spiral discharging, transfer discharging, vibrating discharging or other modes, preferably, the vibrating discharging mode, which is more beneficial for discharging of the steel slag, too high humidity is avoided, and the steel slag adheres to the material outlet 1.

[0031] Specifically, the present application does not limit a type, material, number and arranging position of the transfer mechanisms of the transfer unit 7 as long as the steel slag can be transferred, an angle formed between each transfer mechanism and a horizontal line is set as an inclined angle of the transfer mechanism, the inclined angle of the transfer mechanism may be adjusted at will so as to guarantee that the steel slag can be spread on the transfer mechanism as thin as possible. The transfer mechanism of the present application may be a transfer belt, protrusions are arranged on a belt of each transfer belt and are configured to increase frictional force between the belt and the steel slag, and each transfer belt is arranged at a certain inclined angle and configured to make the steel slag on the last transfer belt fall onto the next transfer belt under an action of gravity. The present application provides an optional example, the transfer mechanisms are two transfer belts, one end of the first transfer belt is arranged at the material inlet and configured to hold steel slag of the material inlet 3, the other end of the first transfer belt is arranged above one end of the second transfer belt, the second transfer belt is configured to hold the steel slag on the first transfer belt and transfer the steel slag to the material outlet 1, and by arranging the two transfer belts, spreading of the steel slag can be better achieved, and thus the steel slag makes full contact with the industrial waste gas.

[0032] Specifically, the present application does not limit a type, an arrangement position and an arrangement number of the spray thrower 4 as long as the environment humidity in the apparatus can be maintained in a range from 80% to 100%, and optionally, the spray thrower 4 is a plurality of liquid drop spray throwers which are uniformly arranged at the top of the apparatus so as to guarantee that the environment humidity in the apparatus is uniform.

[0033] Before carbon fixation of the steel slag in the examples and the comparative examples of the present application, an initial content of the free calcium oxide is 8%, an initial content of chlorine is 0.015%, and an initial content of sulfur is 0.07%.

Example 1

[0034] This example provides a method for steel slag carbon fixation, and the specific steps and the method are as follows:

[0035] 1. it is controlled before feeding that 50% of steel slag has a particle diameter being less than or equal to 80 m, and feeding is performed under a condition of guaranteeing that a water content of the steel slag is 10%, where the water content of the steel slag is controlled by spraying water to the steel slag.

[0036] 2. A feeding amount of the steel slag is 1 t/h, and an inclined angle of each transfer mechanism is controlled to be 15.

[0037] 3. The humidity in the apparatus is maintained to be 80% by continuously spraying reclaimed water drops into the apparatus, meanwhile, the industrial waste gas containing CO.sub.2 is blown in, a volume proportion of CO.sub.2 in the industrial waste gas containing CO.sub.2 is greater than or equal to 25%, an injection rate of the industrial waste gas is 150,000 m.sup.3/h, a temperature of the industrial waste gas is 150 C., and a pressure intensity of the apparatus body is 1.5 atm.

[0038] 4. A transfer rate of the transfer mechanism is controlled to be 1 m/min, so running time of the steel slag in the apparatus is 1 h, namely, the time of contact between the steel slag and the industrial waste gas in the apparatus body is 1 h.

Example 2

[0039] This example provides a method for steel slag carbon fixation, and the specific steps and the method are as follows:

[0040] 1. it is controlled before feeding that 70% of steel slag has a particle diameter being less than or equal to 80 m, and feeding is performed under a condition of guaranteeing that a water content of the steel slag is 5%, where the water content of the steel slag is controlled by spraying water to the steel slag.

[0041] 2. A feeding amount of the steel slag is 1.5 t/h, and an inclined angle of each transfer mechanism is controlled to be 25.

[0042] 3. The humidity in the apparatus is maintained to be 100% by continuously spraying industrial wastewater drops into the apparatus, meanwhile, the industrial waste gas containing CO.sub.2 is blown in, a volume proportion of CO.sub.2 in the industrial waste gas containing CO.sub.2 is greater than or equal to 30%, an injection rate of the industrial waste gas is 200,000 m.sup.3/h, a temperature of the industrial waste gas is 200 C., and a pressure intensity of the apparatus body is 1 atm.

[0043] 4. A transfer rate of the transfer mechanism is controlled to be 1.5 m/min, so running time of the steel slag in the apparatus is 2 h, namely, the time of contact between the steel slag and the industrial waste gas in the apparatus body is 2 h.

Example 3

[0044] This example provides a method for steel slag carbon fixation, and the specific steps and the method are as follows:

[0045] 1. it is controlled before feeding that 50% of steel slag has a particle diameter being less than or equal to 80 m, and feeding is performed under a condition of guaranteeing that a water content of the steel slag is 10%, where the water content of the steel slag is controlled by spraying water to the steel slag.

[0046] 2. A feeding amount of the steel slag is 1 t/h, and an inclined angle of each transfer mechanism is controlled to be 15.

[0047] 3. The humidity in the apparatus is maintained to be 80% by continuously spraying reclaimed water drops into the apparatus, meanwhile, the industrial waste gas containing CO.sub.2 is blown in, a volume proportion of CO.sub.2 in the industrial waste gas containing CO.sub.2 is greater than or equal to 25%, a volume content of SO.sub.2 is 150 ppm, an injection rate of the industrial waste gas is 150,000 m.sup.3/h, a temperature of the industrial waste gas is 150 C., and a pressure intensity of the apparatus body is 1.5 atm.

[0048] 4. A transfer rate of the transfer mechanism is controlled to be 1 m/min, so running time of the steel slag in the apparatus is 1 h, namely, the time of contact between the steel slag and the industrial waste gas in the apparatus body is 1 h.

Example 4

[0049] This example provides a method for steel slag carbon fixation, and the specific steps and the method are as follows:

[0050] 1. it is controlled before feeding that 50% of steel slag has a particle diameter being less than or equal to 80 m, and feeding is performed under a condition of guaranteeing that a water content of the steel slag is 15%, where the water content of the steel slag is controlled by spraying water to the steel slag.

[0051] 2. A feeding amount of the steel slag is 1.2 t/h, and an inclined angle of each transfer mechanism is controlled to be 15.

[0052] 3. The humidity in the apparatus is maintained to be 90% by continuously spraying industrial wastewater drops into the apparatus, meanwhile, the industrial waste gas containing CO.sub.2 is blown in, a volume proportion of CO.sub.2 in the industrial waste gas containing CO.sub.2 is greater than or equal to 10%, a volume content of SO.sub.2 is 250 ppm, an injection rate of the industrial waste gas is 230,000 m.sup.3/h, a temperature of the industrial waste gas is 100 C., and a pressure intensity of the apparatus body is 1.2 atm.

[0053] 4. A transfer rate of the transfer mechanism is controlled to be 0.5 m/min, so running time of the steel slag in the apparatus is 0.5 h, namely, the time of contact between the steel slag and the industrial waste gas in the apparatus body is 0.5 h.

Example 5

[0054] This example provides a method for steel slag carbon fixation, and the specific steps and the method are the same as Example 3 and have a difference from Example 3 that a volume content of SO.sub.2 in the industrial waste gas is 300 ppm.

Example 6

[0055] This example provides a method for steel slag carbon fixation, and the specific steps and the method are the same as Example 1 and have a difference from Example 1 that control over a water content of fed steel slag is implemented through soaking.

Example 7

[0056] This example provides a method for steel slag carbon fixation, and the specific steps and the method are as follows: [0057] it is controlled before feeding that 70% of steel slag has a particle diameter being less than or equal to 80 m, and feeding is performed under a condition of guaranteeing that a water content of the steel slag is 5%, where the water content of the steel slag is controlled by spraying water to the steel slag, a structure shown in FIG. 1 is adopted, the steel slag with the water content meeting a standard is transferred onto the transfer mechanisms through a material inlet 3 according to a feeding rate of the steel slag being 1 t/h, the transfer mechanisms are two transfer belts, inclined angles of the two transfer belts are controlled to be 25, the steel slag on the material outlet 1 can be uniformly spread on the transfer belts, meanwhile, the steel slag on the last transfer belt falls onto the next transfer belt under an action of gravity, the steel slag is transferred in the apparatus body 6, at the same time, the spray thrower 4 continuously sprays reclaimed water drops into the apparatus body 6 so as to maintain humidity in the apparatus body 6 to be 100%, meanwhile, the gas inlet 2 blows industrial waste gas containing CO.sub.2 into the apparatus body 6, a proportion of CO.sub.2 in the industrial waste gas containing CO.sub.2 is greater than or equal to 15%, an injection rate of the industrial waste gas is 150,000 m.sup.3/h, a transfer rate of each transfer belt is controlled to be 1.5 m/min, running time of the steel slag in the apparatus body 6 is 2 h, and the steel slag after carbon fixation is completed is discharged through the material outlet 1.

Comparative Example 1

[0058] This comparative example of the present application provides a method for steel slag carbon fixation, and the specific steps and the method are the same as Example 1 and have a difference from Example 1 that environment humidity in the apparatus for steel slag carbon fixation is maintained to be 60%.

Comparative Example 2

[0059] This comparative example of the present application provides a method for steel slag carbon fixation, and the specific steps and the method are the same as Example 1 and have a difference from Example 1 that spraying is not performed in a process of steel slag carbon fixation.

Experimental Example

[0060] A content of free calcium oxide, a content of chlorine and a content of sulfur in the steel slag after being treated by the methods for steel slag carbon fixation in Examples 1 to 5 and Comparative examples 1 to 2 are tested, a test method adopts YB/T140-2009 Method for chemical analysis of steel slag, and test results are shown in Table 1.

TABLE-US-00001 TABLE 1 Test results of steel slag after being treated by the methods for steel slag carbon fixation in Examples 1 to 5 and Comparative examples 1 to 2 Content % Conversion of free Content % Content % ratio % of free calcium oxide of chlorine of sulfur calcium oxide Example 1 2.3 0.022 0.05 71.3 Example 2 2.1 0.02 0.05 73.8 Example 3 1.4 0.021 0.08 82.5 Example 4 1.9 0.019 0.1 76.3 Example 5 3 0.014 0.05 62.5 Comparative 4 0.015 0.06 50 example 1 Comparative 4.2 0.011 0.06 47.5 example 2

[0061] It may be seen that the content of the free calcium oxide, the content of chlorine and the content of sulfur in the steel slag after being treated by the methods for steel slag carbon fixation in Examples 1 to 5 of the present application conform to regulations for chemical components in steel slag powder in a national standard GB/T20491-2017, and as the content of the free calcium oxide in the steel slag treated by the methods is far less than the regulated standard, the steel slag produced by the methods also has wider application potential.

[0062] Apparently, the above examples are merely examples for clear description, but not for limiting the implementations. Those ordinarily skilled in the art can also make modifications or variations in other different forms based on the above description. All implementations do not need to be and cannot be exhaustively cited here. Apparent modifications or variations derived from this still fall within the protection scope of the present disclosure.