CN116899168A - Fly ash composite medicament for effectively removing selenium and arsenic and preparation method thereof - Google Patents

Abstract

The application provides a fly ash composite medicament and a preparation method thereof, wherein the fly ash composite medicament comprises the following components: an inorganic aluminum salt; manganese sulfate; reduced iron powder; activated carbon; wherein the mass ratio of the inorganic aluminum salt to the manganese sulfate to the reducing iron powder to the active carbon is 1-2:0.5-1:1.5-2:0.5-1, wherein the purities of the inorganic aluminum salt, the manganese sulfate, the reductive iron powder and the activated carbon are all more than or equal to 90 percent. The beneficial effects of the application are as follows: the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are mixed together according to a specific proportion to prepare the specific fly ash composite medicament, and in the actual use process, the fly ash composite medicament not only can effectively remove lead, cadmium and zinc in the fly ash, but also can effectively remove selenium and arsenic in the fly ash, so that the fly ash with high selenium and arsenic can be effectively treated, and the treatment efficiency of the fly ash is greatly improved.

Description

Fly ash composite medicament for effectively removing selenium and arsenic and preparation method thereof

Technical Field

The application relates to the technical field of fly ash solidification, in particular to a fly ash composite medicament and a preparation method thereof.

Background

With the increasing population, people generate more and more garbage in daily life, so how to treat the continuously generated household garbage becomes a great difficulty in urban development.

The existing garbage treatment modes are mainly divided into two types: one is to perform landfill treatment, and the other is to perform incineration treatment, but landfill occupies a lot of land, and incineration generates a lot of fly ash, so that it is necessary to effectively treat fly ash generated during incineration.

The existing fly ash solidification and stabilization method mainly uses chemical agents for solidification and stabilization treatment, and most of the chemical agents used in the prior art are sulfur-series organic chelating agents, however, the existing sulfur-series organic chelating agents can only remove cationic species such as lead, cadmium, zinc and the like in the existing fly ash, and cannot remove selenium and arsenic existing in the form of anionic species in the fly ash, so that unnecessary damage can be caused to the produced fly ash, which is unfavorable for the massive incineration treatment of garbage.

Disclosure of Invention

Based on the above, the application aims to provide a fly ash composite medicament and a preparation method thereof, which are used for solving the problems that the prior sulfur series organic chelating agent can only remove cationic species in the prior fly ash and can not effectively remove anionic species in the fly ash.

The first aspect of the embodiment of the application provides a fly ash composite medicament, which comprises the following components:

an inorganic aluminum salt;

manganese sulfate;

reduced iron powder;

activated carbon;

wherein the mass ratio of the inorganic aluminum salt to the manganese sulfate to the reducing iron powder to the active carbon is 1-2:0.5-1:1.5-2:0.5-1, wherein the purities of the inorganic aluminum salt, the manganese sulfate, the reductive iron powder and the activated carbon are all more than or equal to 90 percent.

The beneficial effects of the application are as follows: the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are mixed together according to a specific proportion to prepare the specific fly ash composite medicament, and in the actual use process, the fly ash composite medicament not only can effectively remove lead, cadmium and zinc in the fly ash, but also can effectively remove selenium and arsenic in the fly ash, so that the effective treatment of the fly ash with high selenium and arsenic can be realized, the treatment efficiency of the fly ash is greatly improved, and the fly ash composite medicament is suitable for popularization and use in a large range.

Preferably, the inorganic aluminum salt is one or more of polyaluminum chloride, aluminum sulfate and aluminum trichloride.

Preferably, the iron content in the reductive iron powder is more than or equal to 95%.

Preferably, the manganese content in the manganese sulfate is more than or equal to 60 percent.

Preferably, the inorganic aluminum salt, the manganese sulfate, the reduced iron powder and the activated carbon are all powder agents.

A second aspect of the embodiment of the present application provides a method for preparing a fly ash composite medicament as described above, the method comprising the steps of:

stirring the inorganic aluminum salt, the manganese sulfate, the reduced iron powder and the activated carbon for 20 to 30 minutes by a stirrer to prepare corresponding mixed medicament;

ball milling activation treatment is carried out on the mixed medicament according to the ball-material ratio of 5:1, and screening treatment is carried out on the mixed medicament after the ball milling activation treatment, so that the fly ash composite medicament is prepared.

In the preparation method of the fly ash composite medicament, the step of ball milling and activating the mixed medicament according to the ball-to-material ratio of 5:1 comprises the following steps:

and placing the mixed medicament into a ball mill according to a ball-to-material ratio of 5:1, setting the ball milling rotating speed of the ball mill to 300-400 rpm, and setting the ball milling time of the ball mill to 3-5 hours.

In the above method for preparing the fly ash composite agent, after the step of ball milling and activating the mixed agent according to a ball-to-material ratio of 5:1, the method further comprises:

XRD phase analysis is carried out on the reductive iron powder in the mixed medicament after the ball milling activation treatment so as to judge whether the reductive iron powder after the ball milling activation treatment has reducibility.

In the preparation method of the fly ash composite medicament, the step of screening the mixed medicament after ball milling activation treatment to prepare the fly ash composite medicament comprises the following steps of:

and (5) screening the mixed medicament subjected to ball milling activation treatment by 50-150 meshes.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Drawings

Fig. 1 is an XRD phase analysis chart of reduced iron powder provided in the first embodiment of the present application.

The application will be further described in the following detailed description in conjunction with the above-described figures.

Detailed Description

In order that the application may be readily understood, a more complete description of the application will be rendered by reference to the appended drawings. Several embodiments of the application are presented in the figures. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "mounted" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

The existing fly ash solidification and stabilization method mainly uses chemical agents for solidification and stabilization treatment, and most of the chemical agents used in the prior art are sulfur-series organic chelating agents, however, the existing sulfur-series organic chelating agents can only remove cationic species such as lead, cadmium, zinc and the like in the existing fly ash, and cannot remove selenium and arsenic existing in the form of anionic species in the fly ash, so that unnecessary damage can be caused to the produced fly ash, which is unfavorable for the massive incineration treatment of garbage.

Referring to fig. 1, a fly ash composite agent and a preparation method thereof according to a first embodiment of the present application are shown, and the fly ash composite agent and the preparation method thereof according to the present embodiment can remove lead, cadmium and zinc in fly ash, and can also effectively remove selenium and arsenic in fly ash, so that the effective treatment of high-selenium fly ash can be completed by sequential addition, and further the treatment efficiency of fly ash is greatly improved, and the fly ash composite agent and the preparation method thereof are suitable for large-scale popularization and use.

Specifically, the fly ash composite agent provided in this embodiment comprises the following components:

an inorganic aluminum salt;

manganese sulfate;

reduced iron powder;

activated carbon;

wherein the mass ratio of the inorganic aluminum salt to the manganese sulfate to the reducing iron powder to the active carbon is 1-2:0.5-1:1.5-2:0.5-1, wherein the purities of the inorganic aluminum salt, the manganese sulfate, the reductive iron powder and the activated carbon are all more than or equal to 90 percent. Wherein, it is pointed out that, inorganic aluminum salt mass ratio is 1-2, manganese sulfate mass ratio is 0.5-1, reducing iron powder mass ratio is 1.5-2, active carbon mass ratio is 0.5-1, through above-mentioned reasonable proportion, can effectively promote the reaction efficiency between each medicament, correspondingly shorten reaction time.

In this embodiment, the inorganic aluminum salt is one or more of polyaluminum chloride, aluminum sulfate and aluminum trichloride. In particular, in this embodiment, the polyaluminum chloride, aluminum sulfate and aluminum trioxide provided in this embodiment are all coagulants commonly used by those skilled in the art, and can polymerize and precipitate lead, cadmium, zinc, arsenic and selenium ions in the fly ash and the formed coagulation colloid in the fly ash solidification and stabilization stage and leaching stage, so that lead, cadmium, zinc, arsenic and selenium in the fly ash can be effectively removed.

In this example, the iron content in the reduced iron powder was not less than 95%. More specifically, in this embodiment, it should be noted that the reducing iron powder is used to reduce lead, cadmium and tetravalent selenium ions in the fly ash to water-insoluble simple substances, so that in order to achieve the purpose of removing lead, cadmium and selenium, in the actual reaction process, the reduced products of divalent iron, trivalent iron ions and iron powder in the iron powder provided in this embodiment react with the acidic leaching agent in the fly ash leaching liquid to generate corresponding ferric hydroxide and perform corresponding precipitation in the strong alkaline environment of the fly ash, and at the same time, the ferric hydroxide can co-precipitate with lead, cadmium, zinc, selenium and arsenic in the fly ash, so that lead, cadmium, zinc, selenium and arsenic in the fly ash can be effectively removed.

In this embodiment, the manganese content in the manganese sulfate is equal to or greater than 60%. Further, in this embodiment, it should be noted that in the actual reaction process, the manganese sulfate provided in this embodiment can further react with selenite and arsenate that react in the fly ash, and generate indissolvable manganese selenite and manganese arsenate, so as to achieve the effect of removing selenium and arsenic in the fly ash, and in addition, the solubility of manganese selenite and manganese arsenate is smaller than that of manganese hydroxide, so that manganese ions are easy to react with selenite and arsenate to generate indissolvable substances in the environment of strong alkali of the fly ash.

In this embodiment, the inorganic aluminum salt, the manganese sulfate, the reduced iron powder, and the activated carbon are powder agents. It should be noted that the activated carbon provided in this embodiment has rich pores, large surface area, acid resistance, alkali resistance and relatively stable chemical properties, so that arsenic and selenium in fly ash can be adsorbed well, and the purpose of removing arsenic and selenium is achieved.

In addition, in this embodiment, it should be further noted that, the medicines provided in this embodiment are all powder medicines, and the medicines do not react with each other, and the powder medicines can be used after the uniform mixing ball milling is completed, and the powder medicines can be added through the cement bin in the existing fly ash curing station, so that the treatment efficiency of the fly ash is improved.

Further, for ease of understanding, the present application is further specifically illustrated by the following examples:

example 1

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 1:0.5:1.5:0.5, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all more than 90%, preferably, the inorganic aluminum salt provided in the embodiment is polyaluminum chloride.

Example two

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 2:1:2:1, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all greater than 90%, preferably, the inorganic aluminum salt provided in this embodiment is polyaluminum chloride.

Example III

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 1.5:0.8:1.8:0.8, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all more than 90%, preferably, the inorganic aluminum salt provided in the embodiment is polyaluminum chloride.

Example IV

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 1.6:0.9:1.6:0.8, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all more than 90%, preferably, the inorganic aluminum salt provided in the embodiment is polyaluminum chloride.

Example five

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 1.3:0.7:1.7:0.9, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all more than 90%, preferably, the inorganic aluminum salt provided in the embodiment is polyaluminum chloride.

Example six

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 1.8:0.6:1.7:0.9, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all more than 90%, preferably, the inorganic aluminum salt provided in the embodiment is polyaluminum chloride.

Comparative example one

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 3:1:2:1, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all greater than 90%, preferably, the inorganic aluminum salt provided in this embodiment is polyaluminum chloride.

Comparative example two

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 1:1:1:1, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all greater than 90%, preferably, the inorganic aluminum salt provided in this embodiment is polyaluminum chloride.

Comparative example three

Specifically, in this embodiment, it should be noted that the mass ratio of the inorganic aluminum salt, manganese sulfate, reduced iron powder, and activated carbon in the fly ash composite agent provided in this embodiment is: 2:0.2:1.5:0.5, and the purities of the inorganic aluminum salt, the manganese sulfate, the reducing iron powder and the activated carbon are all more than 90%, preferably, the inorganic aluminum salt provided in the embodiment is polyaluminum chloride.

Further, the mass ratio provided by the above examples and comparative examples is measured and added to fly ash, and then water is added to complete the solidification and stabilization of fly ash, and further, the experimental results generated by the above examples and comparative examples are shown in table 1 below:

TABLE 1

In practical implementation, the fly ash composite agent provided by the embodiment of the application can obviously reduce the concentration of lead, cadmium, zinc, selenium and arsenic in fly ash, so that the generated fly ash can reach the pollution control standard of a domestic refuse landfill, and the effective treatment of the fly ash is completed.

It should be noted that the above implementation procedure is only for illustrating the feasibility of the present application, but this does not represent that the fly ash composite agent and the preparation method thereof of the present application have only one implementation procedure, and instead, the fly ash composite agent and the preparation method thereof of the present application can be incorporated into the feasible embodiments of the present application as long as they can be implemented.

Example seven

The seventh embodiment of the application provides a preparation method of a fly ash composite medicament, which is used for preparing the fly ash composite medicament provided by the embodiment, and comprises the following steps:

stirring the inorganic aluminum salt, the manganese sulfate, the reduced iron powder and the activated carbon for 20 to 30 minutes by a stirrer to prepare corresponding mixed medicament;

ball milling activation treatment is carried out on the mixed medicament according to the ball-material ratio of 5:1, and screening treatment is carried out on the mixed medicament after the ball milling activation treatment, so that the fly ash composite medicament is prepared.

In this embodiment, it should be noted that, the step of performing ball milling activation treatment on the mixed medicament according to a ball-to-material ratio of 5:1 includes:

and placing the mixed medicament into a ball mill according to a ball-to-material ratio of 5:1, setting the ball milling rotating speed of the ball mill to 300-400 rpm, and setting the ball milling time of the ball mill to 3-5 hours.

In this embodiment, it should be noted that, after the step of ball milling and activating the mixed medicament according to a ball-to-charge ratio of 5:1, the method further includes:

XRD phase analysis is carried out on the reductive iron powder in the mixed medicament after the ball milling activation treatment so as to judge whether the reductive iron powder after the ball milling activation treatment has reducibility.

In this embodiment, the step of screening the mixed agent after the ball milling activation treatment to obtain the fly ash composite agent includes:

and (5) screening the mixed medicament subjected to ball milling activation treatment by 50-150 meshes.

In specific implementation, various medicaments can be fully mixed by the preparation method so as to correspondingly improve the activity of various medicaments, so that the reaction efficiency of various medicaments in the fly ash can be further improved, and the treatment efficiency of the fly ash can be correspondingly improved.

In summary, the compound agent for fly ash and the preparation method thereof in the embodiment of the application can remove lead, cadmium and zinc in the fly ash, and can simultaneously and effectively remove selenium and arsenic in the fly ash, so that the effective treatment of high-selenium and high-arsenic fly ash can be completed by sequentially adding, the treatment efficiency of the fly ash is greatly improved, and the compound agent for fly ash is suitable for being popularized and used in a large range.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing examples illustrate only a few embodiments of the application and are described in detail herein without thereby limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.

Claims (9)

1. A fly ash composite medicament, which is characterized by comprising the following components:

an inorganic aluminum salt;

manganese sulfate;

reduced iron powder;

activated carbon;

wherein the mass ratio of the inorganic aluminum salt to the manganese sulfate to the reducing iron powder to the active carbon is 1-2:0.5-1:1.5-2:0.5-1, wherein the purities of the inorganic aluminum salt, the manganese sulfate, the reductive iron powder and the activated carbon are all more than or equal to 90 percent.

2. The fly ash composite medicament according to claim 1, wherein: the inorganic aluminum salt is one or more of polyaluminum chloride, aluminum sulfate and aluminum trichloride.

3. The fly ash composite medicament according to claim 1, wherein: the iron content in the reductive iron powder is more than or equal to 95 percent.

4. The fly ash composite medicament according to claim 1, wherein: the manganese content in the manganese sulfate is more than or equal to 60 percent.

5. The fly ash composite medicament according to claim 1, wherein: the inorganic aluminum salt, the manganese sulfate, the reduced iron powder and the activated carbon are all powder medicaments.

6. A preparation method of a fly ash composite medicament is characterized by comprising the following steps: a fly ash composite medicament for preparing the fly ash composite medicament according to any one of claims 1 to 5, the method of preparing the fly ash composite medicament comprising the steps of:

stirring the inorganic aluminum salt, the manganese sulfate, the reduced iron powder and the activated carbon for 20 to 30 minutes by a stirrer to prepare corresponding mixed medicament;

ball milling activation treatment is carried out on the mixed medicament according to the ball-material ratio of 5:1, and screening treatment is carried out on the mixed medicament after the ball milling activation treatment, so that the fly ash composite medicament is prepared.

7. The method for preparing the fly ash composite medicament according to claim 6, wherein: the ball milling activation treatment of the mixed medicament according to the ball-to-material ratio of 5:1 comprises the following steps:

and placing the mixed medicament into a ball mill according to a ball-to-material ratio of 5:1, setting the ball milling rotating speed of the ball mill to 300-400 rpm, and setting the ball milling time of the ball mill to 3-5 hours.

8. The method for preparing the fly ash composite medicament according to claim 6, wherein: after the step of ball milling and activating the mixed medicament according to the ball-to-material ratio of 5:1, the method further comprises the following steps:

XRD phase analysis is carried out on the reductive iron powder in the mixed medicament after the ball milling activation treatment so as to judge whether the reductive iron powder after the ball milling activation treatment has reducibility.

9. The method for preparing the fly ash composite medicament according to claim 6, wherein: the step of screening the mixed medicament after ball milling activation treatment to prepare the fly ash composite medicament comprises the following steps:

and (5) screening the mixed medicament subjected to ball milling activation treatment by 50-150 meshes.