KR20040069871A - Preparing method of solidifier and solidification of soil thereof - Google Patents

Abstract

PURPOSE: A rapid hardenable solidifier is provided to show high strength(compressive strength of 150-200kg/cm2) when utilized as a soil solidifier, to be effective for disposal of high water-content wastes and to inhibit the elution of the harmful material. CONSTITUTION: The rapid hardenable solidifier is prepared by the steps of: mixing 30-50 wt% of low graded bauxite, 30-40 wt% of lime and 10-20 wt% of gypsum(desulfurized) and firing the mixture in a rotary kiln to produce a clinker comprising 70-80 wt% of calcium sulfoaluminate(4CaO 3Al2O3 SO3), 10-20 wt% of dicalcium silicate(2CaO SiO2), and 5-10 wt% of iron and magnesium-containing silicate; and adding 0.1-10 wt% of anhydrous gypsum, 0.3-3.0 wt% of zinc stearate and 0.3-3.0 wt% of vinyl-based polymer to 100 parts by weight of the clinker and finely pulverizing the mixture at a high speed.

Description

Manufacturing Method of Fast Hardening Material and Soil Solidification Method Using the Same {SPARIDING METHOD OF SOLIDIFIER AND SOLIDIFICATION OF SOIL THEREOF}

The present invention relates to a method for producing a solidified material for solidifying the soil used in civil engineering, construction, or fast-hardening cement solidified material for lightweight foam concrete, as well as for solidifying or stabilizing waste.

The fast-hardening solidified material of the present invention is mixed with about 30 to 50% by weight of low-grade boxsite, about 30 to 40% by weight of limestone and about 10 to 20% by weight of gypsum (desulfurized gypsum) and charged into a rotary kiln at 1200 to 1300 ° C. After calcining for about 2 hours, the mixture was cooled and cooled to about 70 to 80% by weight of calcium sulfoaluminate (4CaO 3Al 2 O 3 SO 3, aka kleinite), about 10 to 20% by weight of dicalcium silicate (2CaO SiO 2), and other iron and magnesium-containing silicates The first step of producing 5 to 10% by weight of the clinker first, and about 0.1 to 10% by weight of anhydrous gypsum, about 0.3 to 3.0% by weight of fatty acid metal salts (such as zinc stearate), and 100 parts by weight of the clinker of the first step. It relates to a method for producing a fast-hardening solid material comprising a second step of adding and mixing about 0.3 to 3.0% by weight of the polymer.

The fast-hardening solidified material of the present invention solidifies or stabilizes powdered hazardous wastes such as solidification of various types of soil, steelmaking dust, sludge of water and sewage, lime sludge, etc., or needs to increase fast hardening and initial strength. It is used for mortar materials of lightweight foamed concrete for on-site casting.

As the prior art related to the present invention, Korean Patent Laid-Open Publication No. 2002-037993, No. 95-018395 discloses the performance of alkali metal salts such as CaCl2, MgCl2, NaCl, KCl, Na2CO3, Na2SO4, MgSO4, CaSO4 mainly in Portland cement. The method of solidifying soil using materials mixed with a water reducing agent, a crude steel, and a thickener for improvement is introduced, and Korean Patent Laid-Open Publication No. 1998-043021 and 2000-073533 disclose CSA cement and It relates to the solidification of soil using calcium ferroaluminate-based fast-hard cement. As a material for lightweight foam concrete, most of Portland cement is used as in Korean Patent Publication No. 2001-028978 and sand or frying ash is used as an additive admixture, or instead of a chemical foaming agent as in Korean Patent Publication No. 2001-007841. Styrofoam powder or waste paper or synthetic fibers, or a fatty acid alcohol or ethylene oxide copolymer as a foaming agent, as in the Republic of Korea Patent Publication No. 2000-026182. However, these methods are limited in use due to difficulty in adjusting parcels and specific gravity due to delay in curing. Moreover, there is the above-mentioned Patent Publication No. 1998-043021 regarding the use of fast-hardening cement, but specific manufacturing methods for chemical components or constituent compounds for materials and detailed data on the composition thereof are not described. It is mentioned that it uses CSA cement.

On the other hand, US Patent Nos. 5,820,302 and 5,472,475 use alkali metal silicates such as calcium silicate and sodium metasilicate in addition to Portland cement, and US Patent Nos. 6,076997 and 5,860,770 use acrylic acid and monomers. Organic binders such as resins, aliphatic monohydric acids, citric acid, fatty acids and fatty alcohols are used. Japanese Laid-Open Patent Publication No. 2001-097759 discloses techniques for solidifying soil and stabilizing materials in which various organic additives are mixed with general Portland cement, calcium aluminate cement, and waste incineration ashes. Solidification using fast-hardening cement, gypsum, polyalkylene glycol, polycarboxylic acid polymer compound is disclosed in the Patent Publication No. 2000-192403, the solidified material consisting of MgCl 2, AlCl 3, CaCl 2, NaCl, cement Publication No. 1996-333573 relates to a solidified material using polyacrylamide, an aqueous polymer, and an alkali metal salt, and Patent Publication No. 1995-291694 using cellulose ether, acetylene glycol, and polyoxyethylene.

In summary, the above-mentioned known technologies generally use Portland cement, calcium aluminate cement, calcium ferroaluminate, and as inorganic additives, various additives such as MgCl2, CaCl2, NaCl, AlCl3, Na2CO3, CaCO3, CaSO4, etc. Alkali metal salts and carboxylic acid, acrylic acid, polyoxyethylene, etc., as an organic additive, mixed with a suitable amount of soil in the process of solidification and foaming concrete production, mainly foaming agent and various admixtures in Portland cement Adopting the way. However, the known technologies have difficulty in use due to the disadvantages described above.

The present invention exhibits faster hardening speed and initial strength than portland cement or fast cement (calcium sulfoaluminate, calcium aluminate, calcium ferroaluminate), which are used as conventional soil solidifying materials, and are inexpensive. By presenting the manufacturing process of hard cement and the compounding ratio of its composition, the method can be produced and produced, and compared with the conventional soil solidification and waste solidification / stabilizing materials, it is fast hard and has excellent compressive strength and bending strength. There is a need for a manufacturing technique of fast curing solids that can be used as soil solidification material, waste solidification / stabilization material, or mortar material for manufacturing lightweight foam concrete, which can effectively suppress elution.

The present invention is mixed with about 30-50% by weight of low-grade boxsite, about 30-40% by weight limestone and about 10-20% by weight of gypsum (desulphurized gypsum), charged into a rotary kiln and fired at 1200-1300 ° C. for about 2 hours. After cooling, about 70 to 80% by weight of calcium sulfoaluminate (4CaO 3 Al 2 O 3 SO 3, aka kleinite), about 10 to 20% by weight of dicalcium silicate (2CaO SiO 2), and about 5 to 10% by weight of other iron and magnesium-containing silicates The first step of producing a clinker consisting of about 0.1 to 10% by weight of anhydrous gypsum, about 0.3 to 3.0% by weight of fatty acid metal salts (such as zinc stearate), and about 0.3% of a vinyl polymer, in 100 parts by weight of the clinker of the first step. The manufacturing method of the fast hardening solid material which consists of a 2nd process of adding and mixing -3.0 weight%.

Specifically, in the manufacturing process of fast cement, first, about 30-50 wt% of low-grade boxsite, about 30-40 wt% of limestone, and about 10-20 wt% of gypsum (desulphurized gypsum) are mixed and rotary Charged into the kiln and calcined for about 2 hours at 1200 ~ 1300 ℃ and cooled to prepare a clinker. Table 1 shows the chemical composition of the clinker powder, quantitatively, the composition of the clinker compound of the present invention is about 70% by weight of calcium sulfoaluminate (4CaO 3Al 2 O 3 SO 3) and about 10-20% by weight of dicalcium silicate (2CaO SiO 2). And in addition to about 5% by weight of iron and magnesium-containing silicates.

Table 1. Chemical Compositions of the Invention Clinker

Finally, in order to manufacture the fast-hardening solidified material of the present invention, about 0.1 to 10% by weight of anhydrous gypsum is added to 100 parts by weight of the clinker, and the dry powder is dried at high speed with a roll mill or a ball mill to have a brain powder of about 4000 to 6000 cm 2 / g. After stirring, the fine powder was added, and about 0.3 to 3.0% by weight of fatty acid metal salts such as zinc stearate and about 0.3 to 3.0% by weight of vinyl polymer such as water-soluble polyvinyl alcohol or polyvinylacetate were added thereto, followed by mixing It is to produce a solid fire. The mixing temperature of these mixtures is preferably 0 to 40 ° C. because they are frozen below 0 ° C. and can be mixed at temperatures above 40 ° C. like the tropics, but generally at 40 ° C. or less. The fast-hardening solidified material of the present invention solidifies or stabilizes the soil and various wastes, and is also used as a base material such as lightweight foamed concrete mortar for on-site casting ondol. Soil in the present invention is defined as a broad soil including steelmaking dust, sludge, lightweight foam concrete mortar, etc. together with the general soil.

In the preparation of the fast-hardening solidified material of the present invention, about 70 to 89% by weight of calcium sulfoaluminate (4CaO 3 Al 2 O 3 SO 3), about 10 to 20% by weight of dicalcium silicate (2CaO SiO 2), and about 5 to about other iron and magnesium-containing silicates About 0.1 to 10% by weight of anhydrous gypsum was added to the clinker composed of 10% by weight, and the fine powder was pulverized by dry with a roll mill or a ball mill to obtain a brain powder of about 4000 to 6000 cm 2 / g. It is to improve the strength of the soil to be solidified by the fineness of fine particles. The reason why the amount of anhydrous gypsum added is 0.1% by weight or more is to allow the cement to exhibit its natural properties, for example, a certain physical strength, and at 10% by weight or more, the flexural strength as a solidifying material is lowered. On the other hand, the amount of the fatty acid metal salt and the vinyl-based polymer added at 0.3 wt% or less did not exhibit the coagulation force as a solidifying material, and at 3.0 wt% or more, the coagulation force was improved, but was limited because they were uneconomical.

The fast-hardening solidified material of the present invention may have different amounts depending on the type of soil, but in the case of Masato and similar soils (see Table 2) formed by denatured granite, it is used as a base material, and here, Portland cement and the present invention Curing is done by adding a fast hardening material of.

Table 2. Physical Properties of Soil Samples

Cured soil solids show physical properties of soil solidified according to KS F 2330 (testing and drying test method of ground cement mixture) according to the addition amount of the fast-hardening solidified material of the present invention as shown in Table 3. As a result, it can be seen that the compressive strength of the soil solidified is 150 ~ 300㎏ / ㎠.

On the other hand, in order to confirm the solidification and stabilization effect of the waste, lime sludge was selected as a sample and the degree of solidification and stabilization effect were examined.

Table 4 shows the chemical composition of the lime sludge. The solidification effect (compressive strength) and stabilization effect (chlorine elution) were tested by changing the amount of the fast-hardening solidified material of the present invention to the sludge as a base material. As a result, as shown in Table 5, the compressive strength was 100-200㎏ / ㎠ and no heavy metal was eluted.

The following examples will illustrate the invention in detail, but the scope of the invention is not limited thereto.

Example 1

Calcium sulfoaluminate (4CaO 3Al2O3 SO3) was mixed with 30 wt% low-grade boxsite, 30 wt% limestone and 10 wt% gypsum (desulphurized gypsum), charged in a rotary kiln, calcined at 1200-1300 ° C for 2 hours and then cooled. A clinker composed of 70% by weight, 10% by weight of dicalcium silicate (2CaO SiO2), and 5% by weight of iron and magnesium-containing silicates was prepared (first step) and 0.5% by weight of dry gypsum in 100% by weight of the clinker obtained in the first step. , 0.3% by weight of zinc stearate and 0.3% by weight of polyvinyl alcohol were added and mixed with a roll mill to finely grind the brain powder to 4000 to 6000 cm 2 / g (second step) to prepare a fast-hardening solid material.

Example 2

Calcium sulfoaluminate (4CaO 3Al2O3 SO3) was cooled by cooling 50% by weight of low-grade boxsite, 40% by weight of limestone and 20% by weight of gypsum (desulphurized gypsum), charged into a rotary kiln and calcining at 1200 to 1300 ° C for 2 hours. ) 80% by weight, 20% by weight of dicalcium silicate (2CaO SiO2), 10% by weight of silicate containing iron and magnesium were prepared. %, 3.0% by weight of zinc stearate and 3.0% by weight of polyvinylacetate were added and mixed with a roll mill to finely grind the powder to be 4000 to 6000 cm 2 / g (second step) to prepare a fast curing solid material.

Example 3 Solidification of Soil

Masato-like soil (see Table 2) formed by weathering modified granite was ground to a particle size of about 5 mm or less and used as a base material. 10 to 20 parts by weight of Portland cement and 5 to 25 parts by weight of the fast-hardening solidifying material of the present invention were added to 100 parts by weight of the base material, and the mixture was adjusted to a water / solid ratio of about 15 to 20%, and then cured by voltage. .

The cured soil solidified material was subjected to the compressive strength and wet-drying loss rate (12 cycles) of the soil solids produced according to KS F 2330 (Testing method of condensation and curling of ground cement mixture) according to the amount of solidified material of the present invention as shown in Table 3. Since the test results of the US Portland Cement Association proposed within 14% of the proposed range, the compressive strength of the soil solids was 150 ~ 300㎏ / ㎠.

Table 3. Physical Properties of Soil Solids According to the Amount of Fast Hardening Material of the Present Invention

*: 20% Portland cement is added instead of the fast hardening material of the present invention

Example 4 Solidification and Stabilization of Wastes (lime sludge)

The lime sludge of the chemical component shown in Table 4 was used as a base material, and the solidification effect (compressive strength) and stabilization effect (chlorine elution) were tested by changing the addition amount of the fast hardening solid material of this invention to this sludge.

Table 4. Chemical Composition of Lime Sludge

10 to 20 parts by weight of the fast-hardening solidifying material of the present invention was added to 100 parts by weight of the base material to extrude and solidify. The solidified lime sludge solidified body had a compressive strength of 100 to 200 kg / cm 2 according to the standard KS F 2330 according to the addition amount of the fast-hardening solidified material of the present invention as shown in Table 5, and no heavy metal was eluted.

Table 5. Effect of Solidification and Stabilization according to the Amount of Fast Hardening Material of the Present Invention

*: When 20 parts by weight of Portland Cement is added

The fast-hardening solidified fire of the present invention is relatively inexpensive to produce by utilizing waste resources, and when used as soil solidified material, it is possible to construct a soil pavement of high strength (compressive strength 150-200㎏ / ㎠) with a small amount. In addition, when used as a solidifying and stabilizing material for wastes, it is effective for the treatment of high water content wastes, and it is possible to minimize the dissolution of harmful substances such as heavy metal ions.

Claims (6)

30 to 50% by weight of low-grade boxsite, 30 to 40% by weight of limestone and 10 to 20% by weight of gypsum (desulphurized gypsum) were calcined in a rotary kiln and then 70 to 80% by weight of calcium sulfoaluminate (4CaO 3 Al 2 O 3 SO 3), di 0.1 to 10% by weight of dry gypsum to 100 parts by weight of the clinker of the first step and the first step of producing a clinker composed of 10 to 20% by weight of calcium silicate (2CaO SiO2) and 5 to 10% by weight of iron and magnesium-containing silicates; A method for producing a fast-hardening solid material, comprising a second step of finely pulverizing at high speed by adding 0.3 to 3.0% by weight of zinc stearate and 0.3 to 3.0% by weight of a vinyl polymer. The method for producing a fast-hardening solidified material according to claim 1, wherein the first step is firing at 1200 to 1300 ° C for 2 hours. The method for producing a fast-hardening solidified material according to claim 1, wherein in the second step, the grinding powder is pulverized to 4000 to 6000 cm 2 / g with a roll mill or a ball mill. The method according to claim 1, wherein in the second step, the vinyl polymer is selected from polyvinyl alcohol or polyvinylacetate and used. 10 to 20 parts by weight of Portland cement and 5 to 10 parts by weight of the fast-hardening solidified material of the present invention are added to 100 parts by weight of powdery soil having a diameter of 5 mm or less, and the water / solid ratio is adjusted to 15 to 20% to squeeze and cure. Construction method of soil solidified body having a compressive strength in the range of 150 ~ 300㎏ / ㎠. 10 to 20 parts by weight of the fast-hardening solidified material of the present invention is added to 100 parts by weight of lime sludge and extruded to obtain a sludge solidified body having a compressive strength in the range of 100 to 200 kg / cm 2.