Full-solid waste-based ready-mixed fluid slurry curing agent and preparation method thereof
Technical Field
The invention belongs to the technical field of building materials, and particularly relates to a full-solid waste-based ready-mixed fluid slurry curing agent and a preparation method thereof.
Background
The ready-mixed fluid slurry solidified soil has the advantages of adjustability and controllability, good stability, convenient construction, low carbon, environmental protection and the like. It has therefore been widely used in infrastructure backfill projects such as highway foundations, pipe gallery grooves, and foundation pits. The pouring mode of premixed fluid slurry can effectively solve the problems of dust emission, construction inconvenience, poor compaction and the like which possibly occur in the traditional backfilling engineering.
Early ready-mix fluid slurry curing agents were typically pure composite cements, portland cements, and the like. Along with the generation of various mineral admixtures, mineral-based curing agents of composite Portland cement such as fly ash, mineral powder, coal gangue and the like are widely applied.
In order to absorb solid waste and realize green sustainable development, if the low-carbon gel material prepared from the whole solid waste can be used as a curing agent of premixed fluid mud, the method is beneficial to reducing carbon emission, realizes the goal of green circulation sustainable development in the building material industry, can also reduce cost, and generates good social benefit and economic benefit.
Disclosure of Invention
In view of the above, in order to solve the above problems, the invention provides a full solid waste-based ready-mixed fluid slurry curing agent and a preparation method thereof, which realize the resource utilization of industrial solid waste, and compared with cement as a curing cementing material, the invention has the advantages of lower cost, greatly reduced carbon emission and good social and economic benefits; the full solid waste-based ready-mixed fluid slurry curing agent prepared by the industrial solid waste composite exciting agent can cure ready-mixed fluid slurry to form pumpable ready-mixed fluid cured soil, so that the construction process in backfilling engineering is simplified, the construction efficiency is improved, and the backfilling cost is reduced.
In order to achieve the above purpose, the technical scheme of the invention is realized as follows:
the invention provides a full solid waste-based ready-mixed fluid slurry curing agent, which comprises the following raw material components in parts by weight: 30-35 parts of granulated blast furnace slag powder; 15-20 parts of carbide slag powder; 13-18 parts of steel slag ultrafine powder; 15-19 parts of light burned desulfurized gypsum; 5-15 parts of harmless aluminum ash; 1-5 parts of an exciting agent.
In some preferred full solid waste-based ready-mixed fluid slurry curing agent embodiments of the invention, the granulated blast furnace slag powder is grade S95.
In some preferred full solid waste-based ready-mixed fluid slurry curing agent embodiments of the invention, the carbide slag powder particle size is less than 0.075mm.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the specific surface area of the steel slag ultra-fine powder is 700m 2 above/Kg, it is used as an auxiliary gel material, has high activity, and compared with common steel slag powder, the 28d activity index can reach 100%.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the light calcined gypsum is anhydrous gypsum (CaSO) after light calcined treatment at 300-350 DEG C 4 ) Or semi-hydrated gypsum (CaSO) 4 ·1/2H 2 O) the gypsum after light firing treatment has good coagulation promoting effect.
In some preferred embodiments of the full solid waste-based ready-mixed fluid slurry curing agent, the harmless aluminum ash is obtained by wet treatment of secondary aluminum ash, is harmless and pollution to the environment, and does not belong to the hazardous waste category.
In some preferred full solid waste-based embodiments of the ready-mixed fluid slurry curing agent of the present invention, the granulated blast furnace slag powder is obtained by: when smelting pig iron, when the temperature reaches 1400-1600 ℃, the fusible mixture formed by the reaction of gangue, ash, cosolvent and other impurities is processed by water quenching and extremely cooling to obtain active granulated blast furnace slag, and then the granulated blast furnace slag is processed by grinding and then screened to obtain the slag with the specific surface area of 400-450 m 2 S95 grade of/KgGranulated blast furnace slag powder is used as a aluminous raw material.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the carbide slag powder is obtained by: drying the waste residue containing water generated during the production of the acetylene chemical raw material by calcium carbide, and crushing, grinding and sieving to obtain the calcium carbide slag powder with the particle size smaller than 0.075mm as the calcium raw material.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the steel slag ultra-fine powder is obtained by: in the process of smelting steel, industrial waste formed at 1500-1700 ℃ and produced after quenching is crushed, screened, impact ground, graded and magnetically separated, steel slag powder with the grain diameter smaller than 0.075mm is taken, and the steel slag powder is ground into steel slag powder with the specific surface area of 700m by an ultrafine ball milling system 2 And (3) obtaining high-activity steel slag ultrafine powder serving as an auxiliary gel material, wherein the 28d activity index of the steel slag ultrafine powder is 100% compared with that of common steel slag powder.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the light calcined gypsum is obtained by: desulfurizing gypsum (CaSO) 4 ·2H 2 O) grinding, sieving, and light-burning at 300-350deg.C to obtain semi-hydrated gypsum (CaSO) 4 ·1/2H 2 O) or anhydrite (CaSO) 4 ) The light-burned desulfurized gypsum obtained by light-burned treatment has good coagulation promoting effect.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the innocuous aluminum ash is obtained by: firstly, nitrogen is removed from aluminum ash to obtain secondary aluminum ash, then, an alkaline leaching defluorination method is utilized to remove fluorine from the secondary aluminum ash to obtain harmless aluminum ash, and the harmless aluminum ash is separated from the dangerous waste category and can be used as an aluminum raw material.
In some preferred embodiments of the present invention, the fully solid waste-based ready-mixed fluid slurry curing agent is powdered sodium silicate (Na 2 O(SiO 2 )x·yH 2 O,Na 2 O≥18%,SiO 2 More than or equal to 60 percent) or adipic acid, has good excitation effect and can not return alkali.
In some preferred embodiments of the fully solid waste-based ready-mixed fluid slurry curing agent of the present invention, the following percentages are by mass:
the main chemical composition of the granulated blast furnace slag powder is as follows: caO41.34%, siO 2 33.67%,Al 2 O 3 14.52%,Fe 2 O 3 0.33%,MgO 6.18%,Na 2 O 0.42%,K 2 O 0.38%,f-CaO0.54%,LOI 0.77%;
The main chemical composition of the carbide slag powder is as follows: caO75.89%, siO 2 3.14%,Al 2 O 3 1.56%,Fe 2 O 3 0.21%,MgO 0.18%,Na 2 O 1.22%,K 2 O 0.53%,SO 3 0.61%,f-CaO 0.50%,LOI 16.16%;
The main chemical composition of the steel slag ultrafine powder is as follows: caO46.12%, siO 2 13.64%,Al 2 O 3 4.21%,Fe 2 O 3 8.68%,MgO 10.84%,Na 2 O 0.32%,K 2 O 0.12%,P 2 O 5 2.75%,f-CaO11.44%,LOI 1.79%;
The main chemical composition of the light burned desulfurized gypsum is as follows: caO42.18%, siO 2 2.74%,Al 2 O 3 2.06%,Fe 2 O 3 0.34%,MgO 1.47%,Na 2 O 0.13%,K 2 O 0.16%,SO 3 49.83%,TiO 2 0.13%,P 2 O 5 0.04%,f-CaO 0.38%,LOI 0.54%;
The main chemical composition of the harmless aluminum ash is as follows: caO1.73%, siO 2 1.28%,Al 2 O 3 81.23%,Fe 2 O 3 1.46%,MgO 7.49%,Na 2 O 0.32%,K 2 O 0.44%,TiO 2 1.35%,f-CaO 1.82%,LOI 2.88%。
The second aspect of the invention provides a method for preparing a full solid waste-based ready-mixed fluid slurry curing agent, which comprises the following steps:
s1, preprocessing industrial solid waste raw materials to obtain granulated blast furnace slag powder, carbide slag powder, steel slag ultrafine powder, light burned desulfurized gypsum and harmless aluminum ash;
s2, weighing the following raw material components in parts by weight: 30-35 parts of granulated blast furnace slag powder; 15-20 parts of carbide slag powder; 13-18 parts of steel slag ultrafine powder; 15-19 parts of light burned desulfurized gypsum; 5-15 parts of harmless aluminum ash; 1-5 parts of an exciting agent;
s3, uniformly mixing the weighed raw material components, and ball-milling the mixture at a speed of between 250 and 300rmp to enable the excitant to be uniformly attached to the surfaces of other raw material components, thereby improving the hydration activity and obtaining the curing agent.
In some preferred embodiments of the method for preparing the full solid waste-based ready-mixed fluid slurry curing agent of the present invention, the pretreatment method in S1 is as follows:
granulating blast furnace slag powder: when smelting pig iron, taking a fusible mixture formed by reacting gangue, ash, cosolvent and other impurities when the temperature reaches 1400-1600 ℃, quenching the fusible mixture with water to be extremely cold to obtain active granulated blast furnace slag, and screening the granulated blast furnace slag with the specific surface area of 400-450 m after grinding 2 S95-grade granulated blast furnace slag powder of/Kg is used as a silicon-aluminum raw material;
carbide slag powder: drying the waste residue containing water generated during the production of the acetylene chemical raw material by calcium carbide, and then crushing, grinding and sieving to obtain calcium carbide slag powder with the particle size smaller than 0.075mm as a calcium raw material;
steel slag superfine powder: in the process of smelting steel, industrial waste formed at 1500-1700 ℃ and produced after quenching is crushed, screened, impact ground, graded and magnetically separated, steel slag powder with the grain diameter smaller than 0.075mm is taken, and the steel slag powder is ground into steel slag powder with the specific surface area of 700m by an ultrafine ball milling system 2 More than Kg, obtaining high-activity steel slag ultrafine powder as an auxiliary cementing material;
light burned desulfurized gypsum: desulfurizing gypsum (CaSO) 4 ·2H 2 O) grinding, sieving, light burning at 300-350 deg.C,making it into semi-hydrated gypsum (CaSO) 4 ·1/2H 2 O) or anhydrite (CaSO) 4 ) The light-burned desulfurized gypsum obtained through light-burned treatment has good coagulation promoting effect;
harmless aluminum ash: firstly, nitrogen is removed from aluminum ash to obtain secondary aluminum ash, then, an alkaline leaching defluorination method is utilized to remove fluorine from the secondary aluminum ash to obtain harmless aluminum ash, and the harmless aluminum ash is separated from the dangerous waste category and can be used as an aluminum raw material.
In some preferred embodiments of the method of preparing the all solid waste-based ready-mixed fluid slurry curing agent of the present invention, the activator is powdered sodium silicate (Na 2 O(SiO 2 )x·yH 2 O,Na 2 O≥18%,SiO 2 Not less than 60%) or adipic acid; the powdery sodium silicate is alkaline and the adipic acid is acidic, so that the excitation effect of the powdery sodium silicate and the adipic acid is good, and no alkali is returned.
The third aspect of the invention provides ready-mixed fluid slurry solidified soil, which is pumpable ready-mixed fluid slurry solidified soil formed by cementing after the slurry is prepared from dregs with the water content of 35-40 percent and the ready-mixed fluid slurry solidifying agent of the full solid waste base is added; the mixing amount of the full solid waste base ready-mixed fluid slurry curing agent is 20-30% of the weight of the dregs.
The fourth aspect of the invention provides a method for preparing premixed fluid slurry solidified soil, which comprises the steps of pulping dregs with water content of 35-40%; then adding the full solid waste-based ready-mixed fluid slurry curing agent to form pumpable ready-mixed fluid slurry curing soil; the mixing amount of the full solid waste base ready-mixed fluid slurry curing agent is 20-30% of the weight of the dregs.
The action mechanism of the ready-mixed fluid slurry curing agent provided by the invention is as follows:
the innocuous aluminum ash, granulated blast furnace slag powder and carbide slag powder contained in the raw materials of the ready-mixed fluid slurry curing agent respectively provide an aluminum source, a silicon source and calcium hydroxide which are required by the volcanic ash effect, and the specific chemical reactions under the existence of an exciting agent are as follows:
potential reaction of aluminum ash with carbide slag powder: ca (OH) 2 +Al 2 O 3 +H 2 O→C-A-H
Potential reaction of granulated blast furnace slag powder with carbide slag powder: ca (OH) 2 +SiO 2 +H 2 O→C-S-H
Reaction of carbide slag powder, harmless aluminum ash and light burned desulfurized gypsum:
potential reaction of hydration of steel slag ultra-fine powder to produce gel: c (C) 3 S(C 2 S)+H 2 O→C-S-H+CH
The various hydrated gels produced by the reaction enable the ready-mixed fluid slurry curing agent to have certain mechanical strength in different ages.
Compared with the prior art, the full-solid waste-based ready-mixed fluid slurry curing agent and the preparation method thereof have the following advantages:
(1) The full solid waste-based ready-mixed fluid slurry curing agent is prepared from an industrial solid waste composite exciting agent, has certain mechanical strength in different ages when in use, and meets the use requirement; compared with cement used as a curing cementing material, the cost is lower, the carbon emission is greatly reduced, the recycling of industrial solid waste is realized, and good social benefit and economic benefit are generated;
(2) The full solid waste-based ready-mixed fluid slurry curing agent can be used for curing ready-mixed fluid slurry to form pumpable ready-mixed fluid cured soil, so that the construction process in backfilling engineering can be simplified, the construction efficiency can be improved, and the backfilling cost can be reduced;
(3) The full solid waste-based ready-mixed fluid slurry curing agent adopts the specific surface area of 400-450 m 2 S95-grade granulated blast furnace slag powder of/Kg is used as a silicon-aluminum raw material; the steel slag superfine powder with the grain diameter smaller than 0.075mm is used as a calcareous raw material; with a specific surface area of 700m 2 The steel slag superfine powder with high activity of more than/Kg is used as an auxiliary gel material, and compared with common steel slag powder, the 28d activity index of the steel slag superfine powder can reach 100%; adopts the light passingThe light burned desulfurized gypsum after the burning treatment brings good coagulation promoting effect; adopting harmless aluminum ash after harmless treatment as an aluminum raw material; then, powdery sodium silicate or adipic acid with good excitation effect is used as an exciting agent; the obtained ready-mixed fluid slurry curing agent has good slurry curing performance and meets the mechanical strength requirement.
Drawings
FIG. 1 is a schematic diagram of the mechanism of action of a ready-mixed fluid slurry curing agent according to the present invention;
FIG. 2 shows a curing process of ready-mixed fluid slurry according to the present invention.
Detailed Description
Unless defined otherwise, technical terms used in the following examples have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods are conventional methods unless otherwise specified.
The present invention will be described in detail with reference to the following examples and drawings.
Examples 1 to 3
In examples 1 to 3, the all-solid waste-based ready-mixed fluid slurry curing agent was prepared by, unless otherwise specified:
step one, preprocessing industrial solid waste raw materials:
granulating blast furnace slag powder: when smelting pig iron, taking a fusible mixture formed by reacting gangue, ash, cosolvent and other impurities when the temperature reaches 1400-1600 ℃, quenching the fusible mixture with water to be extremely cold to obtain active granulated blast furnace slag, and screening the granulated blast furnace slag with the specific surface area of 400-450 m after grinding 2 S95-grade granulated blast furnace slag powder of/Kg;
carbide slag powder: drying the waste residue containing water generated in the process of producing acetylene and other chemical raw materials by calcium carbide in a drying oven at 105 ℃ for 2.0h, and then mechanically crushing and grinding the waste residue and sieving the waste residue with a 200-mesh sieve to obtain calcium carbide slag powder with the particle size smaller than 0.075mm;
steel slag superfine powder: 1500-1700 parts are taken in the process of smelting steelThe industrial waste formed at the temperature and produced after quenching is crushed, screened, impact ground, graded and magnetically separated, the steel slag powder with the grain diameter less than 0.075mm is taken, and the steel slag powder is ground into the steel slag powder with the specific surface area of 700m by an ultrafine ball milling system 2 More than/Kg, obtaining high-activity steel slag ultrafine powder;
light burned desulfurized gypsum: feeding the smoke-discharging desulfurization gypsum into a Fahrenheit mill for grinding, discharging the smoke-discharging desulfurization gypsum, screening, and carrying out light burning treatment in a muffle furnace at 300-350 ℃ to obtain semi-hydrated gypsum or anhydrous gypsum, thereby obtaining light-burning desulfurization gypsum;
harmless aluminum ash: calcining aluminum ash at 800 ℃ for about 60min to remove AlN to obtain secondary aluminum ash, soaking the secondary aluminum ash for 24h by 10% NaOH through an alkaline leaching defluorination method, and then adding a small amount of CaO to carry out F - Ion precipitation to obtain harmless aluminum ash;
the main chemical compositions of the obtained granulated blast furnace slag powder, carbide slag powder, steel slag ultrafine powder, light burned desulfurized gypsum and harmless aluminum ash are shown in table 1:
TABLE 1 chemical composition of industrial solid wastes
Step two, weighing raw material components according to the parts by weight shown in the table 2;
table 2 Table 1-3 of the fully solid waste-based ready-mixed fluid slurry curing agent formulation
S3, uniformly mixing the weighed raw material components through a mixer, and ball-milling for 15min at 250-300 rmp through a planetary ball mill, so that the exciting agent is uniformly attached to the surfaces of other raw material components, and the full solid waste-based ready-mixed fluid slurry curing agent is obtained.
Comparative example 1
Mineral-based slurry curing materials are commercially available from certain companies.
Performance test experiment 1
The mechanical property test piece is prepared by adopting the following method:
1) After the slag soil with the water content of 35% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 1, wherein the adding amount is 30% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 1;
2) After the slag soil with the water content of 35% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 2, wherein the adding amount is 30% of the weight of the slag soil, so as to obtain a ready-mixed fluid slurry hardening test piece 2;
3) After the slag soil with the water content of 35% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 3, wherein the adding amount is 30% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 3;
4) After the dregs with the water content of 35% are pulped, adding a mineral-based slurry curing material sold by a certain company in comparative example 1, wherein the adding amount is 30% of the weight of the dregs, and obtaining a commercial comparative sample 1;
mechanical property tests were carried out on the ready-mixed fluid slurry hardening test pieces 1 to 3 and the commercial comparative sample 1, and the test results are shown in Table 3.
TABLE 3 mechanical Properties of hardened test pieces (1)
Performance test experiment 2
The mechanical property test piece is prepared by adopting the following method:
1) After the slag soil with the water content of 40% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 1, wherein the adding amount is 20% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 4;
2) After the slag soil with the water content of 40% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 2, wherein the adding amount is 20% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 5;
3) After the slag soil with the water content of 40% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 3, wherein the adding amount is 20% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 6;
4) After the dregs with the water content of 40% are pulped, adding a mineral-based slurry curing material sold by a certain company in comparative example 1, wherein the adding amount is 20% of the weight of the dregs, and obtaining a commercial comparative sample 2;
mechanical property tests were carried out on the ready-mixed fluid slurry hardening test pieces 4 to 6 and the commercial comparative sample 2, and the test results are shown in Table 4.
TABLE 4 mechanical Properties of hardened test pieces (2)
Performance test experiment 3
The mechanical property test piece is prepared by adopting the following method:
1) After the slag soil with the water content of 35% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 1, wherein the adding amount is 30% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 7;
2) After the slag soil with the water content of 35% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 2, wherein the adding amount is 30% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 8;
3) After the slag soil with the water content of 35% is pulped, adding the full solid waste base ready-mixed fluid slurry curing agent prepared in the embodiment 3, wherein the adding amount is 30% of the weight of the slag soil, and obtaining a ready-mixed fluid slurry hardening test piece 9;
4) After the dregs with the water content of 35% are pulped, adding a mineral-based slurry curing material sold by a certain company in comparative example 1, wherein the adding amount is 30% of the weight of the dregs, and obtaining a commercial comparative sample 3;
mechanical property tests were carried out on the ready-mixed fluid slurry hardening test pieces 7 to 9 and the commercial comparative sample 3, and the test results are shown in Table 5.
TABLE 5 mechanical Properties of hardened test pieces (3)
From the above data, it is clear that all the ready-mixed fluid slurry curing agents with full solid waste base prepared in examples 1 to 3 have good slurry curing performance, and meet the mechanical strength requirement, and especially the ready-mixed fluid slurry curing agent with full solid waste base prepared in example 3 has the best effect, and the action mechanism is shown in fig. 1 (the situation that the exciting agent is anhydrous sodium silicate is also illustrated in fig. 1).
Example 4
The preparation process of pumpable ready-mixed fluid slurry solidified soil comprises the following steps:
as shown in fig. 2, firstly, the dregs with the water content of 35 to 40 percent are pulped; then adding the fully solid waste-based ready-mixed fluid slurry curing agent (the adding amount is 20-30% of the weight of the dregs) to form pumpable ready-mixed fluid slurry curing soil;
and backfilling the premixed fluid slurry solidified soil to the highway subgrade, the pipe gallery groove and the foundation pit by adopting a pumping mode.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.