CN113307529A

CN113307529A - Composite admixture prepared by corundum smoke dust

Info

Publication number: CN113307529A
Application number: CN202110490255.0A
Authority: CN
Inventors: 庞超明; 杨志远; 唐志远
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2021-05-06
Filing date: 2021-05-06
Publication date: 2021-08-27
Anticipated expiration: 2041-05-06
Also published as: CN113307529B

Abstract

The invention discloses a composite admixture prepared from corundum smoke dust, which comprises 20-55 parts of corundum smoke dust, 6-14 parts of lime, 1-3 parts of ethylene diamine tetraacetic acid, 20-65 parts of volcanic ash active powder, 0-16 parts of cement-based material waste regenerated powder and 0-0.06 part of alcohol amine compound by mass. The composite admixture prepared by the corundum smoke dust solves the problem that the corundum smoke dust is difficult to utilize, and simultaneously, the composite admixture with good performance is prepared, and the cost of concrete is reduced. The composite admixture prepared by using the waste corundum smoke dust as a basic material and simultaneously utilizing other industrial wastes has good activity, good economic benefit and environmental protection benefit and is easy to apply.

Description

Composite admixture prepared by corundum smoke dust

Technical Field

The invention belongs to the field of building materials, and particularly relates to a composite admixture prepared from corundum smoke dust.

Background

Corundum is prepared by smelting various raw materials in an electric arc furnace at 2000 ℃, a large amount of fly ash waste is inevitably generated in the high-temperature smelting process, and the waste is collected to form corundum smoke dust. Approximately 300 million tons of brown corundum are produced in China every year, and 21 million tons of electric melting brown corundum smoke dust are produced every year if the quantity of the smoke dust is calculated according to 7 percent. At present, most corundum smoke dust can only be buried or stocked.

At present, researches and patents on corundum smoke dust are few, the corundum smoke dust is treated by different technical means to extract sylvite and other valuable components, and a process for comprehensively recovering the valuable components in corundum smelting smoke dust containing gallium and potassium is disclosed in patent CN 201210519477.1. The patent CN200910304084.7 discloses a method and a device for producing a powdery mineral admixture from brown corundum smoke dust, which carry out reasonable comprehensive treatment on the brown corundum smoke dust, and extract various substances respectively to obtain sylvite and powdery refractory material mineral admixture. Patent CN200110007269.5 is a method for extracting gallium from smoke dust from corundum arc furnace, adding ingredients into corundum smoke dust, and preparing gallium through material preparation, roasting, grinding, alkaline leaching, separation, alkaline leaching, electrolysis, refining and purification.

However, in the field of building materials, research on utilization of corundum soot in cement-based materials is still blank.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide the composite admixture prepared by using the corundum soot, which improves the cost performance of materials, has good economic benefit and environmental protection benefit and meets the requirement of the national environmental protection policy of energy conservation and emission reduction.

The technical scheme is as follows: the composite admixture prepared by corundum smoke dust comprises, by mass, 20-55 parts of corundum smoke dust, 6-14 parts of lime, 1-3 parts of ethylene diamine tetraacetic acid, 20-65 parts of volcanic ash active powder, 0-16 parts of cement-based material waste regenerated powder and 0-0.06 part of alcohol amine compounds.

Furthermore, the corundum smoke dust is waste smoke dust collected during corundum smelting, and the specific surface area is more than or equal to 800m²/kg。

Further, SiO in the corundum smoke dust₂、Al₂O₃And K₂The total content of O is more than 75%, wherein, SiO₂30-60% of Al₂O₃The content of (B) is 10% -30%, K₂The content of O is 10 to 30 percent.

Further, the cement-based material waste regenerated powder comprises one or more of regenerated concrete powder, regenerated foam concrete powder, regenerated aerated concrete powder, regenerated baking-free lightweight aggregate powder and regenerated assembly type concrete member powder.

Further, the specific surface area of the cement-based material waste regeneration powder is more than or equal to 300m²And/kg, the CaO content in the powder is measured to be more than or equal to 15 percent by adopting a fluorescence method.

Furthermore, the lime comprises quicklime or slaked lime, and the CaO content of the lime is more than or equal to 75 percent.

Further, the volcanic ash active powder comprises one or more of slag micropowder, fly ash and volcanic ash.

Further, the 28d activity index of the volcanic ash active powder is more than or equal to 70 percent.

Further, the purity of the ethylene diamine tetraacetic acid is more than or equal to 99%.

Further, the alcohol amine compound comprises one or more of diethanol monoisopropanolamine, monoethanol diisopropanolamine, triethanolamine and triisopropanolamine, and the purity of the alcohol amine compound is more than or equal to 99%.

Further, when the composite admixture is used, the proportion of the composite admixture replacing cement is 10% -60%.

Has the advantages that:

a composite admixture prepared by corundum smoke dust solves the problem that corundum smoke dust is difficult to utilize, and provides a feasible utilization scheme.

Vitreous SiO in corundum smoke₂、Al₂O₃High content, and when it is mixed with water at a ratio of 1:10, the pH value is high>8, but does not have gelling properties by itself, does not react with water, but is basic by itself. The effect of singly supplementing calcium oxide is not good, and by means of the high alkalinity of the calcium oxide and the synergistic effect of the calcium oxide and the volcanic ash powder, the ethylene diamine tetraacetic acid, the alcohol amine compounds and the Al³⁺The combination of (a) and (b) can accelerate the dissociation of the metal by achieving the gelling properties of the corundum soot.

The corundum smoke dust contains higher potassium content, can fully stimulate the activity of regenerated cement-based powder and volcano powder, can improve the compressive strength of cement mortar or concrete at various ages compared with the same amount of fly ash and the cement mortar adopting lime to stimulate the fly ash,

the volcanic ash powder has higher long-term strength and durability guarantee rate.

The composite admixture prepared by the corundum smoke dust solves the problem that the corundum smoke dust is difficult to utilize, and simultaneously, the composite admixture with good performance is prepared, and the cost of concrete is reduced. The composite admixture prepared by using the waste corundum smoke dust as a basic material and simultaneously utilizing other industrial wastes has good activity, good economic benefit and environmental protection benefit and is easy to apply.

Detailed Description

The technical solution of the present invention is further explained below.

Example 1

A composite admixture prepared from corundum soot dust is used for preparing cement mortar, and a cementing material is composed of P.II 52.5 cement and the composite admixture, wherein the cementing material comprises sand and water in a ratio of 1:3: 0.5.

The composite admixture is prepared from the following raw materials in parts by weight: 20 parts of corundum smoke dust, 65 parts of fly ash, 14 parts of slaked lime and 1 part of ethylene diamine tetraacetic acid. The cementing materials used in the preparation of the cement mortar comprise the following components in parts by weight: 40 parts of cement and 60 parts of composite admixture.

Example 2

The composite admixture is prepared from the following raw materials in parts by weight: 44.97 parts of corundum smoke dust, 45 parts of fly ash, 8 parts of lime, 2 parts of ethylene diamine tetraacetic acid and 0.03 part of diethanol monoisopropanolamine. The cementing materials used in the preparation of the cement mortar comprise the following components in parts by weight: 40 parts of cement and 60 parts of composite admixture.

Example 3

The composite admixture is prepared from the following raw materials in parts by weight: 55 parts of corundum smoke dust, 20 parts of mineral powder, 6 parts of quicklime, 16 parts of regenerated powder and 3 parts of ethylene diamine tetraacetic acid. The cementing materials used in the preparation of the cement mortar comprise the following components in parts by weight: 70 parts of cement and 30 parts of composite admixture.

Comparative example 1

Pure corundum smoke dust is used as a cementing material for preparing cement mortar, wherein the cementing material comprises sand and water in a ratio of 1:3: 0.5.

Comparative example 2

A composite admixture prepared from corundum soot dust is used for preparing cement mortar, and a cementing material is composed of P.II 52.5 cement and the composite admixture, wherein the cementing material comprises sand and water in a ratio of 1:3: 0.5. When 95 parts of fly ash and 5 parts of lime are used as admixtures to prepare cement mortar, 40 parts of cement and 60 parts of composite admixture are used as cementing materials by weight.

Comparative example 3

The composite admixture is prepared from the following raw materials in parts by weight: 47 parts of corundum smoke dust, 45 parts of fly ash and 8 parts of lime. The cementing materials used in the preparation of the cement mortar comprise the following components in parts by weight: 40 parts of cement and 60 parts of composite admixture

Comparative example 4

When the pure fly ash is used as the admixture for preparing cement mortar, the weight portions of the used cementing materials are as follows: 70 parts of cement and 30 parts of composite admixture.

The performance strength test methods of the examples and comparative examples of the present invention were carried out in accordance with the Cement mortar Strength test method (IOS method) (GB/T17671-1999).

The properties of the products prepared in examples 1 to 3 and comparative examples 1 to 4 are shown in Table 1.

TABLE 1 comparison of mechanical properties of comparative examples and examples

It can be seen from comparative example 1 that the pure corundum powder has no gelling properties and no strength at all ages.

Comparing example 1 and example 2 with comparative example 2, it was found that when the same admixture amount of 60% was used, the compressive strength of the admixtures of examples 1 and 2 was increased over the admixtures of comparative example 2 using lime-activated fly ash at all ages.

Comparing example 2 with comparative example 3, it was found that comparative example 3, in which no ethylenediaminetetraacetic acid and alkanolamine compound were added, had a decrease in strength at each stage of example 2 when the amount of admixture was 60%.

The comparison between example 3 and comparative example 4 shows that when the blending amount of the admixture is 30%, the compression strength of the admixture formulation in example 3 is increased compared with that of the admixture prepared by only using pure fly ash in comparative example 4 at each age.

Claims

1. The composite admixture prepared by using the corundum smoke dust is characterized by comprising 20-55 parts of corundum smoke dust, 6-14 parts of lime, 1-3 parts of ethylene diamine tetraacetic acid, 20-65 parts of volcanic ash active powder, 0-16 parts of cement-based material waste regenerated powder and 0-0.06 part of alcohol amine compound by mass.

2. The composite admixture prepared from corundum smoke dust according to claim 1, wherein the corundum smoke dust is waste smoke dust collected during corundum smelting, and the specific surface area is more than or equal to 800m²/kg。

3. The admixture according to claim 1 or 2, wherein the corundum soot is SiO in the corundum soot₂、Al₂O₃And K₂The total content of O is more than 75%, wherein, SiO₂30-60% of Al₂O₃The content of (B) is 10% -30%, K₂The content of O is 10 to 30 percent.

4. The composite admixture prepared from corundum smoke dust according to claim 1, wherein the cement-based material waste regenerated powder comprises one or more of regenerated concrete powder, regenerated foam concrete powder, regenerated aerated concrete powder, regenerated baking-free lightweight aggregate powder and regenerated fabricated concrete member powder.

5. The composite admixture prepared by using corundum soot as claimed in claim 1 or 4, wherein the specific surface area of the cement-based material waste reclaimed powder is not less than 300m²And/kg, the CaO content in the powder is measured to be more than or equal to 15 percent by adopting a fluorescence method.

6. The composite admixture prepared from corundum soot as defined in claim 1 wherein said lime comprises quicklime or slaked lime having a CaO content of 75% or more.

7. The composite admixture prepared from corundum smoke dust according to claim 1, wherein the volcanic ash active powder comprises one or more of slag micropowder, fly ash and volcanic ash; the 28d activity index of the volcanic ash active powder is more than or equal to 70 percent.

8. The admixture prepared by using corundum soot as defined in claim 1, wherein said purity of ethylenediaminetetraacetic acid is not less than 99%.

9. The composite admixture prepared from corundum soot as claimed in claim 1, wherein the alkanolamine compound comprises one or more of diethanol monoisopropanolamine, monoethanoldiisopropanolamine, triethanolamine and triisopropanolamine, and the purity thereof is not less than 99%.

10. The admixture prepared by using corundum soot as claimed in claim 1, wherein the proportion of the admixture replacing cement is 10-60% when in use.