A method for producing an electromagnetic shielding cement-based material

Abstract

The application discloses a preparation method of an electromagnetic shielding cement-based material, and comprises the following steps: step one, modifying iron-containing solid waste: adsorbing carbon powder on the surface of the iron-containing solid waste to form a surface modified material of the iron-containing solid waste; step two, controlling the distribution position of the iron-containing solid waste by using a magnetic material: setting the material of at least one of the upper top surface, the lower bottom surface, the left side surface and the right side surface of a cement mold as a magnetic material, and adsorbing the surface modified material of the iron-containing solid waste obtained in step one on the surface of the magnetic material; step three, pouring the cement-based slurry material from the lower bottom surface pouring inlet of the mold upwards to the top of the mold, and demolding after hardening to form the cement-based material with the electromagnetic shielding function. The method can prepare the electromagnetic shielding cement-based material by using the iron-containing solid waste, can make the cement-based material have stronger electromagnetic shielding capacity, and can be used to reduce the adverse effects of electromagnetic pollution on human life and production.

Description

Technical Field

[0001] The present invention belongs to the technical field of building materials and relates to a method for preparing an electromagnetic shielding cement-based material, and in particular to a method for preparing an electromagnetic shielding cement-based material by utilizing iron-containing solid waste. Background Art

[0002] While technological advancements have brought convenience to our lives, they have also led to environmental pollution and damage. The widespread use of electromagnetic products and equipment has led to a significant increase in electromagnetic radiation, posing a significant threat to human health. Therefore, suppressing electromagnetic radiation has become an urgent issue. Cement is the most widely used building material due to its low cost. The development of new cements with electromagnetic shielding properties could increase their application value, prevent the leakage of electronic information within buildings, reduce environmental pollution from external electromagnetic radiation sources, and safeguard the safety of electronic information and the health of people. Summary of the Invention

[0003] To reduce the harm electromagnetic pollution causes to human health, the present invention provides a method for preparing an electromagnetic shielding cement-based material. This method utilizes iron-containing solid waste to produce the electromagnetic shielding cement-based material, resulting in a cement-based material with enhanced electromagnetic shielding capabilities, thereby reducing the adverse effects of electromagnetic pollution on human life and production.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A method for preparing an electromagnetic shielding cement-based material comprises the following steps:

[0006] Step 1: Modify the iron-containing solid waste: adsorb carbon powder on the surface of the iron-containing solid waste to form a surface modified material of the iron-containing solid waste, wherein:

[0007] The iron-containing solid waste has an iron content of 15-18%, a particle size of 150-200 μm, and a dosage of 5-10% of the cement mass;

[0008] The carbon powder has a particle size of 20-30 nm and a specific resistance of 0.1-0.2 Ω·cm. 2 , the dosage is 0.1~0.2% of the mass of iron-containing solid waste;

[0009] The modification method is a ball milling method or an electrostatic adsorption method; when the ball milling method is used to modify the iron-containing solid waste, zirconia balls with an equal particle diameter of 10-15 mm are selected, the ball milling time is 45-90 minutes, the revolution speed of the ball milling tank is 150-200 revolutions per minute, the rotation speed is 420-440 revolutions per minute, the volume ratio of balls to materials is 2:1.1, and the volume ratio of the ball materials to the ball milling tank is 4:5; when the electrostatic adsorption method is used to modify the iron-containing solid waste, an electrostatic generator is used to generate static electricity, the voltage is 10-15 kV, the boost is 1.2 kV, the discharge mode is air discharge, the discharge mode is automatic discharge, the interval is 2 s, and the total number of times is 5000-7000 times;

[0010] Step two, the distribution position of the iron-containing solid waste is controlled by using a magnetic material: the material of at least one of the upper top surface, the lower bottom surface, the left side surface and the right side surface of the cement mold is set as a magnetic material, and the surface modification material of the iron-containing solid waste obtained in step one is adsorbed on the surface of the magnetic material;

[0011] Step three, the cement-based slurry material is poured upwards from the pouring inlet of the lower bottom surface of the mold to the top of the mold, and after hardening, the mold is removed to form a cement-based material with an electromagnetic shielding function, wherein:

[0012] The material of the mold is polymethyl methacrylate, and the color is transparent;

[0013] The cement-based slurry material is composed of ordinary Portland cement, water, water reducing agent, nano silicon oxide, etc., the cement fineness is 32-38 μm, the water-cement ratio is 0.26-0.18, the water reducing agent is a polycarboxylic acid water reducing agent, the dosage is 0.5-2.5% of the mass of the cement, and the dosage of nano silicon oxide is 0.5-0.8% of the mass of the cement;

[0014] The ascending speed of the cement-based slurry material is 0.5-1.5 mm / s, and the demolding time is 55-85 h.

[0015] Compared with the prior art, the present application has the following advantages:

[0016] (1) The cement-based material prepared by the present application has good electromagnetic shielding function.

[0017] (2) The present application makes full use of the mineral composition characteristics of the iron-containing solid waste, effectively improves the added value by greatly exerting the component characteristics, and is beneficial to reduction and wide application.

[0018] (3) The addition of the iron-containing solid waste material in the present application reduces the cement consumption and reduces the carbon emissions caused by the use of cement. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The material forming mold in Example 1;

[0020] Figure 2 This is the material forming mold in Example 2. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further described below with reference to the accompanying drawings, but is not limited thereto. Any modification or equivalent replacement of the technical solution of the present invention that does not depart from the spirit and scope of the technical solution of the present invention should be included in the scope of protection of the present invention.

[0022] Example 1:

[0023] This embodiment provides a method for preparing an electromagnetic shielding cement-based material, the method comprising the following steps:

[0024] Step 1: Using a method of ball milling carbon powder and iron-containing solid waste, the carbon powder is adsorbed on the surface of the iron-containing solid waste particles to form the main component minerals of the surface structure of the cement-based material, wherein:

[0025] The iron-containing solid waste has an iron content of 15%, a particle size of 150 μm, and a content of 8% of the cement mass;

[0026] The particle size of the carbon powder is 25 nm, and the amount of the carbon powder is 0.1% of the mass of the iron-containing solid waste;

[0027] The ball milling balls are zirconia balls with a particle diameter of 15 mm, the ball milling time is 60 minutes, the revolution speed of the ball mill is 200 rpm, the rotation speed is 420 rpm, the ball-to-material volume ratio is 2:1.1, and the ball-to-material and ball mill volume ratio is 4:5.

[0028] Step 2: Use magnetic materials to control the distribution of iron-containing solid waste: set the material of the top surface of the cement mold to magnetic material, and set the material of the other surfaces to polymethyl methacrylate, which is transparent in color; adsorb the surface modification material of the iron-containing solid waste obtained in step 1 on the surface of the magnetic material.

[0029] Step 3: Figure 1 As shown, during casting, the cement-based slurry is poured upward from the inlet on the bottom surface of the mold until it contacts the surface of the magnetic material. After hardening, the slurry is demoulded to form a cement-based material with electromagnetic shielding function, wherein:

[0030] The cement-based slurry material is composed of ordinary Portland cement, water, a water-reducing agent, nano-silica, etc. The cement fineness is 35 μm, the water-cement ratio is 0.20, the water-reducing agent is a polycarboxylate water-reducing agent, the addition amount of which is 1.5% of the cement mass, and the addition amount of nano-silica is 0.6% of the cement mass;

[0031] The cement-based slurry material has a rising speed of 1.0 mm / s and a demoulding time of 65 h.

[0032] Example 2

[0033] The present embodiment provides a preparation method of an electromagnetic shielding cement-based material, which comprises the following steps:

[0034] Step one, using an electrostatic generator to generate static electricity on the surface of the iron-containing solid waste, adsorbing carbon powder on the surface of the iron-containing solid waste to form the main component mineral of the surface structure of the cement-based material, wherein:

[0035] The iron-containing solid waste contains 18% of iron, with a particle size of 200 μm, and a dosage of 10% of the mass of the cement;

[0036] The particle size of the carbon powder is 30 nm, and the dosage is 0.2% of the mass of the iron-containing solid waste;

[0037] The voltage of the electrostatic generator is 15 kV, the boost is 1.2 kV, the discharge mode is air discharge, the discharge mode is automatic discharge, the interval is 2 s, and the total number is 6000 times.

[0038] Step two, using a magnetic material to control the distribution position of the iron-containing solid waste: the top surface, left side and right side of the cement mold are made of magnetic material, and the bottom surface is made of polymethyl methacrylate, with transparent color; the surface modification material of the iron-containing solid waste obtained in step one is adsorbed on the surface of the magnetic material.

[0039] Step three, as shown in Figure 2 , when pouring and forming, the cement-based slurry is poured from the lower bottom entrance of the mold to the surface of the magnetic material, and after hardening, the mold is removed to form a cement-based material with electromagnetic shielding function, wherein:

[0040] The material of the mold is polymethyl methacrylate, and the color is transparent;

[0041] The cement-based slurry material is composed of ordinary portland cement, water, water reducing agent, nano silicon oxide, etc., with a cement fineness of 32 μm, a water-cement ratio of 0.25, a water reducing agent of polycarboxylic acid water reducing agent, a dosage of 2.0% of the mass of the cement, and a dosage of 0.8% of the mass of the cement;

[0042] The rising speed of the cement-based slurry material is 1.5 mm / s, and the demolding time is 75 h.

Claims

1. A method for preparing an electromagnetic shielding cement-based material, characterized in that The method comprises the following steps: Step 1: Modifying the iron-containing solid waste: adsorbing carbon powder on the surface of the iron-containing solid waste to form a surface-modified material for the iron-containing solid waste, wherein: the amount of the iron-containing solid waste is 5-10% by weight of the cement, and the amount of the carbon powder is 0.1-0.2% by weight of the iron-containing solid waste; the iron content of the iron-containing solid waste is 15-18%, and the particle size is 150-200 μm; the method for modifying the iron-containing solid waste is ball milling or electrostatic adsorption; The ball milling balls are zirconia balls with a particle diameter of 10-15 mm, the ball milling time is 45-90 minutes, the revolution speed of the ball mill is 150-200 rpm, the rotation speed is 420-440 rpm, the ball-to-material volume ratio is 2:1.1, and the ball-to-material volume ratio is 4:5; The electrostatic adsorption method uses an electrostatic generator to generate static electricity, with a voltage of 10-15 kV, a boost of 1.2 kV, an air discharge mode, an automatic discharge mode, a 2-s interval, and a total number of 5000-7000 times; Step 2: Using a magnetic material to control the distribution of the iron-containing solid waste: Setting the material of at least one of the top surface, bottom surface, left side surface, and right side surface of the cement mold to be a magnetic material, and adsorbing the surface modification material of the iron-containing solid waste obtained in step 1 on the surface of the magnetic material; Step 3: Pour the cement-based slurry material from the pouring inlet on the bottom surface of the mold upward to the top of the mold, and demould it after hardening to form a cement-based material with electromagnetic shielding function.

2. The method for preparing the electromagnetic shielding cement-based material according to claim 1, characterized in that The carbon powder has a particle size of 20-30 nm and a specific resistance of 0.1-0.2 Ω·cm. 2 .

3. The method for preparing the electromagnetic shielding cement-based material according to claim 1, characterized in that The cement-based slurry material consists of ordinary Portland cement, water, a water reducer, and nano-silica. The cement fineness is 32-38 μm, the water-cement ratio is 0.26-0.18, the water reducer is added in an amount of 0.5-2.5% of the cement mass, and the nano-silica is added in an amount of 0.5-0.8% of the cement mass.

4. The method for preparing the electromagnetic shielding cement-based material according to claim 3, characterized in that The water reducer is a polycarboxylic acid water reducer.

5. The method for preparing the electromagnetic shielding cement-based material according to claim 1, characterized in that The cement-based slurry material has a rising speed of 0.5-1.5 mm / s and a demoulding time of 55-85 h.

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