An emulsion modifier and its application in heavy metal control of coal gasification slag

Abstract

The application discloses an emulsion modifier and application thereof in heavy metal prevention and control of coal gasification slag, and belongs to the field of mining and environmental protection. The method comprises the following steps: adding 0.1-10 parts of the emulsion modifier into 100 parts of the coal gasification slag, modifying the coal gasification slag with a certain particle size interval by using a mixer or a ball mill and the like for a certain time, and performing aging and drying treatment to obtain modified coal gasification slag; wherein the emulsion modifier is configured and reacted by 0-50 parts of organic silicon resin, 0-50 parts of epoxy resin, 0-50 parts of styrene-acrylic emulsion, 1-5 parts of silane coupling agent and 0-2 parts of naphthalene sulfonate. The application has the advantages of simple treatment process, and can prevent and control the precipitation of heavy metal ions such as Al, Cu, Zn, As, Se, Cr and Pb in the coal gasification slag, and reduce the environmental pollution hazard of the coal gasification slag.

Description

Technical Field

[0001] This invention belongs to the fields of mining and environmental protection, and specifically relates to an emulsion modifier and its application in the control of heavy metals in coal gasification slag. Background Technology

[0002] Heavy metals such as lead, cadmium, chromium, and arsenic are commonly found in coal gasification slag. Their content is significantly influenced by the origin of the raw coal and the gasification process parameters, with some indicators exceeding the limits set by the "Soil Environmental Quality Standard for Agricultural Land Soil Pollution Risk Control" (GB15618-2018) and "Construction Sand" (GB / T 14684-2022). During the resource utilization of coal gasification slag, heavy metals are easily released through leaching and volatilization, causing secondary pollution. Therefore, controlling the release of heavy metals from coal gasification slag is a major challenge.

[0003] For the control of heavy metals in coal gasification slag, CN202510766435.5 describes a carbon-nano zero-valent iron composite material based on coal gasification slag and its preparation method, which can achieve efficient removal of Cr(VI) from water within 5 minutes (removal rate of 78.9%) and has significant structural stability. CN202510046907.X describes an oxidative leaching separation treatment system and method for heavy metals in coal gasification slag, which utilizes chemical oxidants to pre-oxidize and change the binding form of heavy metals in the solid in strongly stable bound states such as oxides, chlorides, carbonates or complex compounds, thereby improving the migration performance of heavy metals. Then, acidic leaching agents are used to elute and separate the easily migrating heavy metals from the solid through proton exchange and organic chelation. CN202510029082.0 describes a harmless treatment system and method for coal gasification slag, which achieves harmless treatment of coal gasification slag through screening, grinding, sorting, compound leaching, chemical oxidation and water washing adjustment. Existing methods for controlling heavy metals in coal gasification slag are cumbersome to operate, costly, and have limited capacity for heavy metal removal.

[0004] Therefore, this invention proposes a modification method using emulsion as a modifier and employing a mixer or ball mill to modify coal gasification slag. This process is simple, low-cost, and can achieve the goal of controlling heavy metals, aiming to provide a new method for heavy metal prevention and control, coal-based solid waste treatment, and green mining. Summary of the Invention

[0005] Purpose of the invention: In order to overcome the shortcomings of the existing technology, the present invention provides an emulsion modifier and its application in the control of heavy metals in coal gasification slag. The low-cost organic modifier controls the precipitation of heavy metal ions such as Al, Cu, Zn, As, Se, Cr, and Pb in coal gasification slag, reduces the pollution and harm of coal gasification slag to the environment, improves the utilization rate of solid waste, and achieves the goal of green mining.

[0006] Technical solution: To achieve the above objectives, the technical solution adopted by this invention is as follows:

[0007] The first objective of this invention is to provide an emulsion modifier for the control of heavy metals in coal gasification slag, wherein the emulsion modifier comprises the following components by weight:

[0008] 1-150 parts resin emulsion, 1-5 parts silane coupling agent, 0.1-2 parts naphthalene sulfonate and 0.1-1 parts defoamer, wherein the resin emulsion is selected from 0-50 parts organic resin, 0-50 parts epoxy resin and 0-50 parts styrene-acrylic emulsion.

[0009] The organic resin includes one or more of polyethylene, polycarbonate, and polyamide;

[0010] The epoxy resin includes one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin.

[0011] Optionally, in one embodiment of the present invention, the resin emulsion comprises 5-10 parts polycarbonate, 10-20 parts bisphenol A type epoxy resin, and 10-15 parts styrene-acrylic emulsion.

[0012] Optionally, in one embodiment of the present invention, the emulsion modifier comprises 50-100 parts of resin emulsion, 2-5 parts of silane coupling agent, 0.5-2 parts of naphthalene sulfonate and 0.3-1 parts of defoamer.

[0013] Optionally, in one embodiment of the present invention, the silane coupling agent is selected from one or more of aminosilane coupling agents or epoxysilane coupling agents. Preferably, the silane coupling agent is selected from aminosilane coupling agents, and the aminosilane coupling agent includes aminopropyltriethoxysilane coupling agent.

[0014] Optionally, in one embodiment of the present invention, the naphthalene sulfonate is selected from one or more of high polymer condensates, alkyl derivatives, monomeric monosulfonates, or monomeric disulfonates. Preferably, the naphthalene sulfonate is selected from monomeric monosulfonates, wherein the monomeric monosulfonate includes β-naphthalenesulfonic acid.

[0015] Optionally, in one embodiment of the present invention, the defoamer is selected from one or more of solid powder defoamers, polyether-modified silicone, or emulsion silicone. Preferably, the defoamer is selected from solid powder defoamers, which include hydrophobic fumed silica.

[0016] Optionally, in one embodiment of the present invention, the preparation method of the emulsion modifier includes: placing an antifoaming agent into a stirred reactor, then adding a resin emulsion and stirring at a stirring speed of 500-1000 r / min, then adding a silane coupling agent and a naphthalene sulfonate dropwise into the stirred reactor, continuing to stir for 30-60 min after the dropwise addition is completed, and then continuing the ultrasonic dispersion reaction for 12-24 hours.

[0017] Optionally, in one embodiment of the present invention, the power of the ultrasonic dispersion is 20-100 kHz.

[0018] The second objective of this invention is to provide a method for controlling heavy metals in coal gasification slag. This method involves modifying the coal gasification slag with any of the emulsion modifiers described above to control heavy metal ions, including Al, Cu, Zn, As, Se, Cr, and Pb. According to this modification method, the precipitation of heavy metal ions such as Al, Cu, Zn, As, Se, Cr, and Pb in the coal gasification slag is controlled, thereby reducing the environmental pollution hazards caused by the coal gasification slag.

[0019] Optionally, in one embodiment of the present invention, the modification treatment of coal gasification slag includes: weighing 100 parts of coal gasification slag, adding 0.1-10 parts of emulsion modifier, mixing and grinding with a mixer or ball mill, and obtaining modified coal gasification slag after aging and drying.

[0020] Optionally, in one embodiment of the present invention, 5-10 parts of emulsion modifier are added to the 100 parts of coal gasification slag.

[0021] Optionally, in one embodiment of the present invention, the emulsion modifier is added to the coal gasification slag by dripping or spraying, and the dripping or spraying time should be greater than 5 minutes.

[0022] Optionally, in one embodiment of the present invention, the particle size range of the coal gasification slag is 0.001-2 mm.

[0023] Optionally, in one embodiment of the present invention, the modification treatment takes 10-60 minutes.

[0024] Optionally, in one embodiment of the present invention, the aging time is 6-12 hours.

[0025] Optionally, in one embodiment of the present invention, the drying method includes baking or sun-drying.

[0026] Further optionally, in one embodiment of the invention, the drying temperature is 40-60°C.

[0027] A third objective of this invention is to provide an organically modified coal gasification slag, prepared according to the above method.

[0028] The fourth objective of this invention is to provide an application of the above-described method or organic-modified coal gasification slag in the field of environmental protection.

[0029] Beneficial Effects: Compared with existing methods for modifying coal gasification slag and controlling heavy metals, the emulsion modifier provided by this invention and its application in the control of heavy metals in coal gasification slag have the following advantages:

[0030] (1) Organic materials are low in cost, have simple processing technology, and are highly feasible;

[0031] (2) Organic matter is used to coat the coal gasification slag, reducing the contact between water and heavy metals, controlling the precipitation of heavy metals (Al, Cu, Zn, As, Se, Cr, Pb), and reducing the harm of heavy metals to the soil, water sources and other environments;

[0032] (3) The modified coal gasification slag can still be used for filling material preparation, building material production, etc., to improve the utilization rate of coal-based solid waste and promote the resource utilization of solid waste. Attached Figure Description

[0033] Figure 1 This is a SEM image of the coal gasification slag before modification.

[0034] Figure 2 This is a SEM image of the modified coal gasification slag. Detailed Implementation

[0035] The purpose of this invention is to provide an emulsion modifier and its application in the control of heavy metals in coal gasification slag. The main method is to use organic emulsion as a modifier, aiming to optimize the modification cost and process of coal gasification slag, improve the utilization rate of coal gasification slag, control the environmental hazards caused by heavy metal precipitation, and achieve environmental protection and green mining.

[0036] This invention relates to an emulsion modifier and its application in the control of heavy metals in coal gasification slag, belonging to the fields of mining and environmental protection. The materials required for the organic modification process of coal gasification slag in this invention are: 0-50 parts of organosilicon resin, 0-50 parts of epoxy resin, 0-50 parts of styrene-acrylic emulsion, 1-5 parts of silane coupling agent, and 0-2 parts of naphthalene sulfonate. For every 100 parts of coal gasification slag, 0.1-10 parts of the emulsion modifier are required.

[0037] The method for modifying organic matter and controlling heavy metals in coal gasification slag according to the present invention includes the following steps:

[0038] S1. Modifier preparation: Emulsion modifier (0-50 parts organic resin and / or 0-50 parts epoxy resin and / or 0-50 parts styrene-acrylic emulsion), 1-5 parts silane coupling agent, 0.1-2 parts naphthalene sulfonate, 0.1-1 parts defoamer, etc. are prepared into a modifier, mixed and stirred and ultrasonically dispersed to allow it to react fully for a certain period of time;

[0039] S2. Modification of coal gasification slag: Weigh 100 parts of coal gasification slag, add 0.1-10 parts of the prepared modifier to the dried coal gasification slag within a certain particle size range, and perform the modification treatment by mixing and grinding with a mixer or ball mill for a certain period of time, and then age for a certain period of time.

[0040] S3. Drying treatment: The modified coal gasification slag is dried to obtain modified coal gasification slag.

[0041] S4. Detect the heavy metal content in modified coal gasification slag, for example, using the horizontal oscillation method, X-ray fluorescence spectroscopy, inductively coupled plasma atomic emission spectrometry, etc.

[0042] The present invention will be further described below with reference to embodiments. The present invention can be better understood from the following embodiments. However, those skilled in the art will readily understand that the specific material ratios, process conditions, and results described in the embodiments are for illustrative purposes only and should not, and will not, limit the present invention as described in detail in the claims.

[0043] Example 1

[0044] S1. Preparation of Modifier: Weigh 50 parts of polycarbonate, 1 part of γ-aminopropyltriethoxysilane coupling agent, 0.1 part of β-naphthalenesulfonic acid and 0.1 part of hydrophobic fumed silica as solid powder defoamer. First, put the solid powder defoamer into a stirred reactor, then add polycarbonate and stir in the stirred reactor at a stirring speed of 500 r / min. Then, add γ-aminopropyltriethoxysilane coupling agent and β-naphthalenesulfonic acid dropwise into the stirred reactor. After the dropwise addition is completed, continue stirring for 30 minutes. Finally, use an ultrasonic power of 20 Hz and continue stirring for 12 hours to obtain the emulsion modifier.

[0045] S2. Modification of coal gasification slag: 100 parts of coal gasification fine slag and 0.1 parts of the prepared emulsion modifier are put into a ball mill for modification treatment for 30 minutes, and then aged for 6 hours after the treatment.

[0046] S3. Drying treatment: Place it in a drying oven and dry it at 60°C for 24 hours to obtain the modified coal gasification slag.

[0047] Example 2

[0048] S1. Preparation of Modifier: Weigh 50 parts of bisphenol A type epoxy resin, 1 part of γ-aminopropyltriethoxysilane coupling agent, 0.5 parts of β-naphthalenesulfonic acid and 0.1 parts of hydrophobic fumed silica as solid powder defoamer. First, put the solid powder defoamer into a stirred reactor, then add bisphenol A type epoxy resin and stir in the stirred reactor at a stirring speed of 500 r / min. Then, add γ-aminopropyltriethoxysilane coupling agent and β-naphthalenesulfonic acid dropwise into the stirred reactor. After the dropwise addition is completed, continue stirring for 30 minutes. Finally, use an ultrasonic power of 20 Hz and continue stirring for 12 hours to obtain the emulsion modifier.

[0049] S2. Modification of coal gasification slag: 100 parts of coal gasification fine slag and 0.1 parts of the prepared emulsion modifier are put into a ball mill for modification treatment for 30 minutes, and then aged for 6 hours after the treatment.

[0050] S3. Drying treatment: Place it in a drying oven and dry it at 60°C for 24 hours to obtain the modified coal gasification slag.

[0051] Example 3

[0052] S1. Preparation of Modifier: Weigh 50 parts of styrene-acrylic emulsion, 1 part of γ-aminopropyltriethoxysilane coupling agent, 1 part of β-naphthalenesulfonic acid, and 0.1 parts of hydrophobic fumed silica as solid powder defoamer. First, put the solid powder defoamer into a stirred reactor, then add styrene-acrylic emulsion and stir in the stirred reactor at a stirring speed of 500 r / min. Then, add γ-aminopropyltriethoxysilane coupling agent and β-naphthalenesulfonic acid dropwise into the stirred reactor. After the dropwise addition is completed, continue stirring for 30 minutes. Finally, use an ultrasonic power of 20 Hz and continue stirring for 12 hours to obtain the emulsion modifier.

[0053] S2. Modification of coal gasification slag: 100 parts of coal gasification fine slag and 0.1 parts of the prepared emulsion modifier are put into a ball mill for modification treatment for 30 minutes, and then aged for 6 hours after the treatment.

[0054] S3. Drying treatment: Place it in a drying oven and dry it at 60°C for 24 hours to obtain the modified coal gasification slag.

[0055] Example 4

[0056] S1. Preparation of Modifier: Weigh 50 parts of polycarbonate, 50 parts of bisphenol A epoxy resin, 5 parts of γ-aminopropyltriethoxysilane coupling agent, 1 part of β-naphthalenesulfonic acid, and 0.5 parts of hydrophobic fumed silica as solid powder defoamer. First, put the solid powder defoamer into a stirred reactor, then add polycarbonate and bisphenol A epoxy resin and stir in the stirred reactor at a stirring speed of 500 r / min. Then, add γ-aminopropyltriethoxysilane coupling agent and β-naphthalenesulfonic acid dropwise into the stirred reactor. After the dropwise addition is completed, continue stirring for 30 minutes. Finally, use an ultrasonic power of 20 Hz and continue stirring for 12 hours to obtain the emulsion modifier.

[0057] S2. Modification of coal gasification slag: 100 parts of coal gasification fine slag and 1 part of the prepared emulsion modifier are put into a ball mill for modification treatment for 30 minutes, and then aged for 6 hours after the treatment.

[0058] S3. Drying treatment: Place it in a drying oven and dry it at 60°C for 24 hours to obtain the modified coal gasification slag.

[0059] Example 5

[0060] S1. Preparation of Modifier: Weigh 50 parts of polycarbonate, 50 parts of bisphenol A epoxy resin, 5 parts of γ-aminopropyltriethoxysilane coupling agent, 1 part of β-naphthalenesulfonic acid, and 0.5 parts of hydrophobic fumed silica as solid powder defoamer. First, put the solid powder defoamer into a stirred reactor, then add polycarbonate and bisphenol A epoxy resin and stir in the stirred reactor at a stirring speed of 500 r / min. Then, add γ-aminopropyltriethoxysilane coupling agent and β-naphthalenesulfonic acid dropwise into the stirred reactor. After the dropwise addition is completed, continue stirring for 30 minutes. Finally, use an ultrasonic power of 20 Hz and continue stirring for 12 hours to obtain the emulsion modifier.

[0061] S2. Modification of coal gasification slag: 100 parts of coal gasification fine slag and 5 parts of the prepared emulsion modifier are put into a ball mill for modification treatment for 30 minutes, and then aged for 6 hours after treatment.

[0062] S3. Drying treatment: Place it in a drying oven and dry it at 60°C for 24 hours to obtain the modified coal gasification slag.

[0063] Example 6

[0064] S1. Preparation of Modifier: Weigh 50 parts of polycarbonate, 50 parts of bisphenol A epoxy resin, 5 parts of γ-aminopropyltriethoxysilane coupling agent, 1 part of β-naphthalenesulfonic acid, and 0.5 parts of hydrophobic fumed silica as solid powder defoamer. First, put the solid powder defoamer into a stirred reactor, then add polycarbonate and bisphenol A epoxy resin and stir in the stirred reactor at a stirring speed of 500 r / min. Then, add γ-aminopropyltriethoxysilane coupling agent and β-naphthalenesulfonic acid dropwise into the stirred reactor. After the dropwise addition is completed, continue stirring for 30 minutes. Finally, use an ultrasonic power of 20 Hz and continue stirring for 12 hours to obtain the emulsion modifier.

[0065] S2. Modification of coal gasification slag: 100 parts of coal gasification fine slag and 10 parts of the prepared emulsion modifier are put into a ball mill for modification treatment for 30 minutes, and then aged for 6 hours after the treatment.

[0066] S3. Drying treatment: Place it in a drying oven and dry it at 60°C for 24 hours to obtain the modified coal gasification slag.

[0067] The organic-modified coal gasification slag obtained in each embodiment was subjected to performance testing. The testing methods included horizontal oscillation method to measure the content of heavy metal ions such as Cu, Cr, and Pb, SEM and other methods to measure its microstructure, and the adsorption performance of heavy metals after modification. The results are as follows.

[0068] Table 1 Experimental Results

[0069]

[0070] Table 1 above shows that, compared with the control group before modification, the leaching of most heavy metal elements (Al, Cu, Zn, As, Se, Cr, Pb) in the modified coal gasification slag is significantly reduced, especially the leaching of elements such as Zn and Cr, which is reduced by several times.

[0071] Figure 1 , Figure 2 SEM images of the coal gasification slag before and after modification are shown. The microstructure of the coal gasification slag before and after modification can be observed. The surface of the coal gasification slag changes from a loose state to a granular state coated with emulsion, and the particle size also increases.

[0072] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An emulsion modifier for heavy metal control in coal gasification slag, characterized in that, By weight, emulsion modifiers comprise the following components: 1-150 parts resin emulsion, 1-5 parts silane coupling agent, 0.1-2 parts naphthalene sulfonate and 0.1-1 parts defoamer, wherein the resin emulsion is selected from 0-50 parts organic resin, 0-50 parts epoxy resin and 0-50 parts styrene-acrylic emulsion. The organic resin includes one or more of polyethylene, polycarbonate, and polyamide; The epoxy resin includes one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin.

2. The emulsion modifier according to claim 1, characterized in that, The resin emulsion comprises 5-10 parts polycarbonate, 10-20 parts bisphenol A epoxy resin, and 10-15 parts styrene-acrylic emulsion; and / or The silane coupling agent is selected from one or more of aminosilane coupling agents or epoxysilane coupling agents; and / or The naphthalene sulfonate is selected from one or more of high polymer condensates, alkyl derivatives, monomeric monosulfonates, or monomeric disulfonates; and / or The defoamer is selected from one or more of solid powder defoamers, polyether-modified silicone, or emulsion silicone.

3. The emulsion modifier according to claim 1, characterized in that, The preparation method of the emulsion modifier includes: placing the defoamer into a stirred reactor, then adding the resin emulsion and stirring at a stirring speed of 500-1000 r / min, then adding the silane coupling agent and naphthalene sulfonate dropwise into the stirred reactor, continuing to stir for 30-60 min after the dropwise addition is completed, and then continuing the ultrasonic dispersion reaction for 12-24 hours. Preferably, the power of the ultrasonic dispersion is 20-100 kHz.

4. A method for controlling heavy metals in coal gasification slag, characterized in that, The coal gasification slag is modified using the emulsion modifier as described in any one of claims 1-3 to control heavy metal ions in the coal gasification slag, wherein the heavy metal ions include Al, Cu, Zn, As, Se, Cr, and Pb.

5. The method according to claim 4, characterized in that, The modification treatment of coal gasification slag includes: weighing 100 parts of coal gasification slag, adding 0.1-10 parts of emulsion modifier, mixing and grinding with a mixer or ball mill, and obtaining modified coal gasification slag after aging and drying.

6. The method according to claim 5, characterized in that, The emulsion modifier is added to the coal gasification slag by dripping or spraying, and the dripping or spraying time should be greater than 5 minutes.

7. The method according to claim 5, characterized in that, The particle size range of the coal gasification slag is 0.001-2 mm.

8. The method according to claim 5, characterized in that, The modification process takes 10-60 minutes.

9. The method according to claim 5, characterized in that, The aging time is 6-12 hours.

10. The method according to claim 5, characterized in that, The drying method includes baking or sun-drying. Preferably, the drying temperature is 40-60°C.

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