阅读说明：本技术 一种铜渣复合材料和其应用 (copper slag composite material and application thereof ) 是由 常兴华 金胜明 崔葵馨 于 2019-09-19 设计创作，主要内容包括：本发明涉及一种铜渣复合材料和应用,该铜渣复合材料主要包括二氧化硅、氧化铁和氧化钙,其中,相对于铜渣复合材料总重量,二氧化硅中硅元素的含量为15-28wt％,氧化铁中铁元素的含量为12-20wt％,氧化钙中钙元素的含量为10-15wt％,可作为制备水泥的活性混合材料。利用本发明的方法制备的水泥的强度能够达到32.5标号水泥的强度标准,是一种环保水泥,本发明实现了铜渣尾矿的固废资源化利用。(The invention relates to a copper slag composite material and application thereof, wherein the copper slag composite material mainly comprises silicon dioxide, iron oxide and calcium oxide, wherein relative to the total weight of the copper slag composite material, the content of silicon element in the silicon dioxide is 15-28 wt%, the content of iron element in the iron oxide is 12-20 wt%, and the content of calcium element in the calcium oxide is 10-15 wt%, and the copper slag composite material can be used as an active mixed material for preparing cement. The strength of the cement prepared by the method can reach the strength standard of cement with the grade of 32.5, the cement is environment-friendly cement, and the method realizes the solid waste recycling of the copper slag tailings.)

1. The copper slag composite material is characterized in that: the copper slag composite material mainly comprises silicon dioxide, iron oxide and calcium oxide, wherein the content of silicon element in the silicon dioxide is 15-28 wt%, the content of iron element in the iron oxide is 12-20 wt%, and the content of calcium element in the calcium oxide is 10-15 wt% relative to the total weight of the copper slag composite material.

2. the copper slag composite material according to claim 1, characterized in that: the copper slag composite material also contains a small amount of aluminum oxide, magnesium oxide and titanium dioxide, wherein the content of aluminum element in the aluminum oxide is 3.0-4.1 wt%, the content of magnesium element in the magnesium oxide is 1.5-2.4 wt%, and the content of titanium element in the titanium dioxide is 0.11-0.20 wt% relative to the total weight of the copper slag composite material.

3. a cement, characterized in that: the cement is prepared from the following raw materials in parts by weight:

55-95 parts of cement clinker

5-20 parts of gypsum

6-50 parts of copper slag composite material.

4. A cement according to claim 3, characterized in that: the strength of the cement is greater than the strength standard of 32.5 grade cement;

The copper slag composite material contains silicon dioxide, and the content of silicon element in the silicon dioxide is 15-28 wt% relative to the total weight of the copper slag composite material.

5. A cement according to claim 3, characterized in that: the copper slag composite material also comprises ferric oxide, calcium oxide, aluminum oxide, magnesium oxide and titanium dioxide,

relative to the total weight of the copper slag composite material, the content of iron element in the ferric oxide is 12-20 wt%, the content of calcium element in the calcium oxide is 10-15 wt%, the content of aluminum element in the aluminum oxide is 3.0-4.1 wt%, the content of magnesium element in the magnesium oxide is 1.5-2.4 wt%, and the content of titanium element in the titanium dioxide is 0.11-0.20 wt%;

The particle size of the copper slag composite material is 1-120 μm, preferably 5-70 μm, and more preferably 10-50 μm.

6. A cement according to claim 3, characterized in that: the specific surface area of the copper slag composite material is 5.710-8.560m²Per g, preferably from 6.905 to 7.287m²A,/g, more preferably 7.143m²/g。

7. A preparation method of cement is characterized in that: the method comprises the following steps:

step 1, grinding the copper slag composite material to obtain copper slag powder;

Grinding the cement clinker and the gypsum to obtain mixed powder;

And 3, mixing the copper slag powder and the mixed powder to obtain the cement.

8. The method of claim 7, wherein: in the step 1, the grinding is ball milling, the ball-to-material ratio is 4-8:1, the grinding speed is 10-60rpm, and the grinding time is 30min-6 h.

9. The method of claim 7, wherein: in the step 2, the cement clinker accounts for 55-95 parts by weight, and the gypsum accounts for 5-20 parts by weight.

10. The method of claim 7, wherein: in the step 3, the weight part of the copper slag powder is 6-50 parts.

Technical Field

The invention relates to the field of cement building materials, in particular to cement prepared by utilizing copper ore tailings.

Background

The copper slag is waste slag generated in the process of smelting copper ore at high temperature, the discharge amount of the copper slag is large, the occupied area is large, and great environmental pollution can be caused, so that the problem that enterprises are troubled is solved.

at present, the comprehensive utilization of copper tailings in China mainly comprises modes of recovering useful elements, backfilling a goaf with the copper tailings and the like, but the utilization rate of the comprehensive utilization of the copper tailings is low.

The reason is that the copper tailings are low in valuable element content and difficult to separate, special process flows are needed during recovery tests, some concentrate can meet the taste requirement only by adopting multiple times of fine concentration, and a large amount of secondary tailings are generated after valuable elements are recovered, so that further sodium removal treatment is needed.

And the goaf backfill can be carried out only after the production is stopped, and the copper tailings generated in the early stage still need to build a tailing pond for temporary stockpiling, so that the land is occupied, and the environment is polluted.

How to strengthen the comprehensive utilization of the copper slag, change waste into valuables, realize sustainable development and solid waste resource utilization, reduce the influence of the copper slag on the environment is a problem to be solved urgently at present.

disclosure of Invention

in order to solve the above problems, the present inventors have conducted intensive studies to prepare a cement having a strength that can meet the strength standard of 32.5 grade cement, using a copper slag composite as an active admixture. And the leaching amount of most heavy metals in water in the copper slag composite material does not exceed the national standard, and the cement prepared from the copper slag composite material does not cause heavy metal pollution to the environment, so that the cement is environment-friendly cement, and the invention is completed.

the invention provides a copper slag composite material, which mainly comprises silicon dioxide, iron oxide and calcium oxide, wherein the content of silicon element in the silicon dioxide is 15-28 wt%, the content of iron element in the iron oxide is 12-20 wt%, and the content of calcium element in the calcium oxide is 10-15 wt% relative to the total weight of the copper slag composite material.

The second aspect of the invention provides cement, wherein the cement is prepared from the copper slag composite material of the first aspect of the invention, and the cement is prepared from the following raw materials in parts by weight:

55-95 parts of cement clinker

5-20 parts of gypsum

6-50 parts of copper slag composite material.

In a third aspect, the present invention provides a method for preparing the cement of the second aspect, comprising the steps of:

Step 1, grinding the copper slag composite material to obtain copper slag powder;

Grinding the cement clinker and the gypsum to obtain mixed powder;

And 3, mixing the copper slag powder and the mixed powder to obtain the cement.

Drawings

FIG. 1 shows a particle size distribution diagram of a copper slag composite material;

FIG. 2 shows a nitrogen adsorption isotherm diagram of a copper slag composite;

FIG. 3 shows the phase morphology of the copper slag composite material under a microscope;

FIG. 4 shows the phase morphology of the copper slag composite material under an electron microscope;

FIG. 5 shows a scanning electron microscope image at e in FIG. 3 of the copper slag composite material;

FIG. 6 shows an X-ray energy dispersion spectrum at e in FIG. 3 of the copper slag composite material;

FIG. 7 shows a scanning electron microscope image at c in FIG. 3 of the copper slag composite material;

FIG. 8 shows an X-ray energy dispersion spectrum at c in FIG. 3 of the copper slag composite material;

FIG. 9 shows a scanning electron microscope image at d in FIG. 3 of the copper slag composite material;

FIG. 10 shows an X-ray energy dispersion spectrum at d in FIG. 3 of the copper slag composite material;

FIG. 11 shows a scanning electron microscope image at b in FIG. 3 of the copper slag composite material;

FIG. 12 shows an X-ray energy dispersion spectrum at b in FIG. 3 of the copper slag composite material;

FIG. 13 shows the particle size distribution of copper dross after different ball milling times;

Fig. 14 shows an XRD pattern of the copper slag composite material.

Detailed Description

the invention is explained in more detail below with reference to the figures and examples. The features and advantages of the present invention will become more apparent from the description.

According to a preferred embodiment of the present invention, the particle size of the copper slag composite material is 1 to 120 μm, more preferably 5 to 70 μm, and still more preferably 10 to 50 μm.

according to a preferred embodiment of the invention, the specific surface area of the copper slag composite material is 5.710-8.560m²Per g, more preferably 6.905-7.287m²a,/g, more preferably 7.143m²/g。

According to a preferred embodiment of the present invention, the copper slag composite material mainly comprises silicon dioxide, iron oxide and calcium oxide, wherein the content of silicon element in the silicon dioxide is 15-28 wt%, preferably 15-21 wt%, the content of iron element in the iron oxide is 12-20 wt%, preferably 12-17.3 wt%, and the content of calcium element in the calcium oxide is 10-15 wt%, preferably 10-13.6 wt%, relative to the total weight of the copper slag composite material.

In a further preferred embodiment, the content of silicon element is 18-20.8 wt%, the content of iron element is 14-17.0 wt%, and the content of calcium element is 10-13.2 wt%.

in a further preferred embodiment, the silicon element content is 20.31 wt%, the iron element content is 16.39 wt%, and the calcium element content is 12.69 wt%.

The main components of the portland cement are tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium aluminoferrite, and the main components of the portland cement are calcium oxide, silicon dioxide, aluminum oxide and iron oxide. The copper slag composite material contains a large amount of silicon dioxide, ferric oxide and calcium oxide, and can be used as an active mixed material for producing cement to produce the cement.

the active mixed material of cement is a mixed material which can be mixed with lime, gypsum or silicate cement clinker at normal temperature and can generate hydration reaction after being mixed with water to generate a hydraulic hydration product.

According to a preferred embodiment of the invention, the copper slag composite material further contains a small amount of alumina, magnesia and titania, wherein the content of aluminum element in the alumina is 3.0-4.1 wt%, preferably 3.0-3.65 wt%, relative to the total weight of the copper slag composite material; the content of magnesium element in the magnesium oxide is 1.5-2.4 wt%, preferably 1.5-2.15 wt%; the titanium element content of the titanium oxide is 0.11 to 0.20 wt%, preferably 0.11 to 0.165 wt%.

in a further preferred embodiment, the content of the aluminum element is 3.2 to 3.6 wt%, the content of the magnesium element is 1.7 to 2.1 wt%, and the content of the titanium element is 0.13 to 0.16 wt%.

In a still further preferred embodiment, the content of the aluminum element is 3.57 wt%, the content of the magnesium element is 1.94 wt%, and the content of the titanium element is 0.15 wt%.

in the copper slag composite material, the main existing form of aluminum element is aluminum oxide, the main existing form of magnesium element is magnesium oxide, and the main existing form of titanium element is titanium dioxide.

When the copper slag composite material is used for producing cement, a small amount of titanium dioxide contained in the copper slag composite material can reinforce the hardening process of the cement, but magnesium oxide can affect the stability of the cement, and the content of the magnesium oxide needs to be strictly controlled when the cement is produced.

According to a preferred embodiment of the present invention, the copper slag composite material further contains heavy metal elements such as copper, chromium, manganese, lead, and zinc.

The inventor carries out a toxicity leaching test in water on the copper slag composite material according to a method specified in the national standard 'toxicity leaching method for solid waste' (GB 5086.1-2-1997), and the results are shown in Table 1:

TABLE 1 Leaching toxicity test data of copper slag composites in water

As can be seen from Table 1, the leaching amount of most heavy metals in the copper slag composite material in water is far lower than the national standard and is less than one thousandth of the national standard. Although the national standard does not give the standard value of the manganese element, the leaching amount of manganese is only 31.9 mug/L, belongs to the microgram level and hardly influences the environment. The cement prepared by the copper slag composite material does not cause heavy metal pollution to the environment, and is very environment-friendly.

according to a preferred embodiment of the present invention, the copper slag composite phase consists of a glassy phase and a crystalline phase comprising quartz, calcium oxide, ferric silicate, dicalcium silicate, gehlenite, hedenbergite, and triiron tetroxide; the glassy phase includes iron and calcium sulfides and calcium alumino-iron containing silicates.

in a second aspect, the invention provides a cement prepared using the copper slag composite material of the first aspect of the invention.

according to a preferred embodiment of the present invention, the cement is prepared from the following raw materials in parts by weight:

55-95 parts of cement clinker

5-20 parts of gypsum

6-50 parts of copper slag composite material.

Wherein, the cement clinker refers to Portland cement clinker, which is international Portland cement clinker, and is a hydraulic gel substance with calcium metasilicate as main mineral component, which is prepared by grinding raw materials mainly containing calcium oxide, silicon dioxide, aluminum oxide and ferric oxide into fine powder according to a proper proportion and burning the fine powder until partial melting. According to the main characteristics and purposes of the portland cement clinker, the portland cement clinker can be divided into general cement clinker, low-alkali cement clinker, anti-sulfate cement clinker, high-sulfate cement clinker, moderate-heat cement clinker, low-heat cement clinker and the like.

In the present invention, the cement clinker is not particularly limited, but general-purpose cement clinker is preferable.

In a further preferred embodiment, the cement is prepared from the following raw materials in parts by weight:

80-89 parts of cement clinker

5-15 parts of gypsum

10-30 parts of copper slag composite material.

In a further preferred embodiment, the cement is made from the following raw materials in parts by weight:

80 portions of cement clinker

5 portions of gypsum

15 parts of copper slag composite material.

According to a preferred embodiment of the present invention, the copper slag composite material in the cement raw material is slag remaining after copper ore selection and iron selection treatment of the copper ore of the cuprum of holy mountain of Anhui, which mainly comprises silicon dioxide, wherein the content of silicon element in the silicon dioxide is 15-28 wt%, preferably 15-21 wt%, relative to the total weight of the copper slag composite material.

In a further preferred embodiment, the content of silicon element in the silicon dioxide is 18 to 20.8 wt% relative to the total weight of the copper slag composite material.

In a further preferred embodiment, the content of silicon element in the silica is 20.31 wt% with respect to the total weight of the copper slag composite material.

According to a preferred embodiment of the present invention, the copper slag composite material in the cement raw material further mainly comprises iron oxide, and the content of iron element in the iron oxide is 12-20 wt%, preferably 12-17.3 wt%, relative to the total weight of the copper slag composite material.

in a further preferred embodiment, the content of iron element in the iron oxide is 14-17.0 wt% relative to the total weight of the copper slag composite material.

in a still further preferred embodiment, the iron oxide has an iron element content of 16.39 wt% relative to the total weight of the copper slag composite.

According to a preferred embodiment of the present invention, the copper slag composite material in the cement raw material further mainly comprises calcium oxide, and the content of calcium element in the calcium oxide is 10 to 15 wt%, preferably 10 to 13.6 wt%, relative to the total weight of the copper slag composite material.

In a further preferred embodiment, the calcium oxide has a calcium content of 10 to 13.2 wt% with respect to the total weight of the copper slag composite material.

In a further preferred embodiment, the calcium oxide has a calcium content of 12.69 wt% with respect to the total weight of the copper slag composite material.

According to a preferred embodiment of the present invention, the copper slag composite material in the cement raw material further comprises a small amount of alumina, and the content of aluminum element in the alumina is 3.0 to 4.1 wt%, preferably 3.0 to 3.65 wt%, further preferably 3.2 to 3.6 wt%, and further preferably 3.57 wt% relative to the total weight of the copper slag composite material.

According to a preferred embodiment of the present invention, the copper slag composite material in the cement raw material further comprises a small amount of magnesium oxide, and the content of magnesium element in the magnesium oxide is 1.5 to 2.4 wt%, preferably 1.5 to 2.15 wt%, further preferably 1.7 to 2.1 wt%, and further preferably 1.94 wt% relative to the total weight of the copper slag composite material.

According to a preferred embodiment of the present invention, the copper slag composite material in the cement raw material further comprises a small amount of titanium dioxide, and the content of titanium element in the titanium dioxide is 0.11 to 0.20 wt%, preferably 0.11 to 0.165 wt%, further preferably 0.13 to 0.16 wt%, and further preferably 0.15 wt% relative to the total weight of the copper slag composite material.

According to a preferred embodiment of the present invention, the particle size of the copper slag composite material is 1 to 120 μm, more preferably 5 to 70 μm, and still more preferably 10 to 50 μm.

According to a preferred embodiment of the invention, the specific surface area of the copper slag composite material is 5.710-8.560m²Per g, more preferably 6.905-7.287m²A,/g, more preferably 7.143m²/g。

In a third aspect, the present invention provides a method for preparing cement, comprising the steps of:

step 1, grinding the copper slag composite material to obtain copper slag powder;

The copper slag composite material contains cement active bodies, has gelling activity, but has low activity, and the activity of the copper slag composite material can be excited by grinding. The fineness of the copper slag composite material can be increased by grinding, the specific surface area of the copper slag composite material is increased, a heavy vitreous body of the copper slag composite material is damaged, active minerals such as silicate and aluminate wrapped in the copper slag composite material are exposed, the contact area of the copper slag composite material and water can be increased, and the coagulation of cement is accelerated.

According to a preferred embodiment of the invention, the milling is ball milling.

the ball milling is carried out in the ball mill, on one hand, the grinding ratio of the ball mill is large, and the discharging fineness of the product is easy to adjust. On the other hand, the ball mill has large production capacity, can continuously run for a long time and can meet the requirement of large-scale production.

According to a preferred embodiment of the invention, the ball to feed ratio in the grinding is 4-8:1, more preferably 5-7:1, and even more preferably 6: 1.

The ball-material ratio is too small, the grinding efficiency of the ball mill is low, the ball-material ratio is too large, the load of a cylinder of the ball mill can be increased, and equipment is easily damaged. The inventor finds out through a large number of experiments that the ball milling effect is best when the ball-to-material ratio is 6: 1.

According to a preferred embodiment of the invention, the rotational speed of the milling is 10 to 60rpm, more preferably 20 to 40rpm, even more preferably 25 rpm.

according to a preferred embodiment of the invention, the grinding time is between 30min and 6 h.

in the invention, the ball milling time has a great influence on the particle size of the copper slag composite material, as shown in FIG. 13 and Table 2,

TABLE 2 particle size parameter of copper slag powder after ball milling for different time

The particle size of the untreated copper slag composite material is mainly distributed between 1 and 120 mu m, the particle size is normally distributed, and the untreated copper slag composite material is sieved to obtain D10, D50 and D90 powder. Wherein, the particle size parameters of D10, D50 and D90 respectively represent the corresponding particle sizes when the cumulative particle size distribution number of the copper slag composite material reaches 10%, 50% and 90%. Their physical meaning is that the particles having a particle size smaller (or larger) than it make up 10%, 50% and 90% of the copper slag composite material, respectively.

As can be seen from fig. 13 and table 2, the particle size of the D50 copper slag composite material decreased with the increase of the grinding time, and the particle size decreasing tendency gradually decreased. The particle sizes of the D10 copper slag composite material and the D90 copper slag composite material are firstly reduced and then increased along with the extension of the grinding time, and the reason for the increase of the particle size of the powder is because of the agglomeration of the powder. Therefore, the ball milling time needs to be strictly controlled.

In a further preferred embodiment, the milling time is from 1 to 4 h.

In a further preferred embodiment, the milling time is 2 h.

According to a preferred embodiment of the invention, the copper slag composite material is sieved before grinding, the particle size of the sieved copper slag composite material being 10-50 μm, preferably 15-45 μm, more preferably 20-30 μm.

As can be seen from Table 2, the particle size of the copper slag composite material is mainly and intensively distributed about 20 μm, and the particle size of the copper slag composite material after screening is more uniform, which is helpful for controlling the ball milling condition.

grinding the cement clinker and the gypsum to obtain mixed powder;