KR100648461B1 - A solidification agent for soft ground and sludge improvement strengthen using industrial waste - Google Patents

Abstract

Provided is a solidifying agent composition for the soft ground and sludge treatment, which comprises industrial waste materials pulverized to have an increased unit surface area, thereby activating production of ettringite, and prevents the soil and the ground water from being contaminated with heavy metals. The solidifying agent composition for the soft ground and sludge treatment comprises waste materials generated from various industrial processes, including fly ash, blast furnace slug, lime, anhydrite, cement and potassium alum, the waste materials being pulverized into a predetermined fineness. In the solidifying agent composition, the fly ash has a fineness of 4,000 cm^2/g or more and is used in an amount of 30-60 parts by weight; the blast furnace slag has a fineness of 4,000-6,000 cm^2/g and is used in an amount of 10-40 parts by weight; the lime has a purity of at least 90% and a fineness of 4,000 cm^2/g or more and is used in an amount of 5-20 parts by weight; the anhydrite has a purity of at least 90% and a fineness of 5,000 cm^2/g or more and is used in an amount of 5-20 parts by weight; the cement has a fineness of 4,000-5,000 cm^2/g and is used in an amount of 10-40 parts by weight; and the potassium alum is used in an amount of 5-15 parts by weight based on 100 parts by weight of the anhydrite.

Description

Solidifying agent composition for soft ground and sludge treatment using industrial wastes {A solidification agent for soft ground and sludge improvement strengthen using industrial waste}

The present invention relates to a solidified base composition for treating soft ground and sludge treatment using industrial waste, and more specifically, fly ash, blast furnace slag and quicklime, anhydrous gypsum, cement, etc., which are wastes generated in various industrial processes. The present invention relates to a solidifying agent composition for treating soft ground and sludge using industrial waste for activating the production of ethrinzite by pulverizing to increase the unit surface area to promote solidification.

In general, the solidifying agent is to solidify the soft ground and sludge, and in particular, it forms a hard and physically stable hardened body by reacting with the soft ground and the sludge to strengthen the ground as well as solidifying the hazardous waste. And it prevents the heavy metals, etc. contained in the sludge to play a role to block the contamination of the soil or groundwater in advance.

As such, conventionally, cement or gypsum hardener has been developed and widely used since the 1960s, but it can improve the strength of soft ground and sludge, but in the case of cement, it is economically manufactured by firing at high temperature. In addition to the increased cost, heavy metals such as hexavalent chromium remain, and in particular, lime changes the soil to strong alkalinity, which leads to continuous alkali disturbance and thus limiting the growth of plants. .

On the other hand, the cement-based solidifying agent added with fly ash (Fly ash) can increase the long-term strength and durability by the reaction of calcium hydroxide, slag and anhydrous gypsum produced by the hydration reaction, but it is weak Due to the organic material contained in the ground and sludge, the development of the microstructure is not easy, so that the solidification effect due to the hydration reaction is lowered, which leads to extremely limited workability.

In addition, although the solidifying agent using blast furnace slag as a raw material is not hydrophobic, when cement and water are mixed, curing properties are exhibited through alkali reactions such as fly ash, but this also has a problem that the reaction rate is low and the solidification action is lowered. It became.

Therefore, the present inventor can not only promote the solidification rate of the hardener but also prevent the contamination of the soil and groundwater due to heavy metals discharged from the soft ground and sludge in advance, as well as fly ash and blast furnace chain classified as industrial waste. Various researches have been conducted to recycle slag.

As such, the present invention has been made to solve the conventional problems as described above,

An object of the present invention is to increase the unit surface area by pulverizing fly ash and blast furnace slag, quicklime, anhydrous gypsum, cement, etc., which have been classified as industrial wastes, to have a certain powder level, thereby activating the production of ethrinite, and thus making it soft. An object of the present invention is to provide a solidifying agent composition for treating soft ground and sludge using industrial waste to maximize the solidification effect of the ground and sludge.

Solidified composition for treating soft ground and sludge treatment using the industrial waste of the present invention for achieving the object as described above
In the solidifying agent composition for soft ground and sludge treatment to accelerate the solidification action by grinding fly ash, blast furnace slag and quicklime, anhydrous gypsum, cement, rock cover, etc.

The fly ash is 30 to 60 parts by weight of the powder degree of 4,000 cm 2 / gr or more, the blast furnace slag is 10 to 40 parts by weight of the powder degree of 4,000 ~ 6,000 cm 2 / gr, the quicklime is more than 90% purity and the powder is 4,000 cm 2 / 5-20 parts by weight or more of gr, the anhydrous gypsum has a purity of 90% or more, 5-20 parts by weight of powder of 5,000 cm 2 / gr or more, the cement is 10-40 parts by weight of powder of 4,000-5,000 cm 2 / gr, the girly Alum is composed of 5 to 15 parts by weight relative to 100 parts by weight of anhydrous gypsum.

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Thus, the soft ground and sludge treatment solidifying composition using the industrial waste of the present invention is mixed with the soft ground and the sludge, ethrinzite (lime sulfo aluminate, 3CaOAl ₂ O ₃ 3CaSO through hydration reaction or Pozzolan reaction) _{4 It} uses the principle to solidify the soft ground and sludge by activating the production of 32H ₂ O).

That is, when the soft ground or the sludge is mixed with the present invention, ethrinzite is produced by the hydration reaction of the pore water between the cement and the soil contained in the composition.

At this time, since the composition of the present invention has a certain powder degree, the reactivity is increased to promote the production of ethrinzite.

Therefore, the ethrinzite is to form a crystallization of the needle bed (토양) to fill the gap of the soil to reduce the water content (含水 比), compact the solids, and to fix the harmful heavy metals and organic matter by ion exchange and expansion.

Hereinafter, the solidification composition for treating soft ground and sludge treatment using the industrial waste of the present invention will be described in detail.

In the present invention, the common powder of the composition is preferably maintained at 4,000 ~ 6,000 ㎠ / gr or more, which is the cure rate by absorbing the moisture of the soft ground and sludge by a fast reaction rate when the powder is 4,000 ㎠ / gr or more When it is possible to promote, on the contrary, when the powder is also less than 4,000 cm 2 / gr, the curing rate is significantly lowered, causing a serious problem of heavy metals contained in the soft ground and sludge being absorbed into the ground.

At this time, the pulverizer for pulverizing the composition of the present invention adopts a known vertical roller mill method to proceed with the pulverization of the composition.

<Fly ash>

In the present invention, the fly ash can not lower the moisture contained in the soft ground and sludge by the pozzolanic reaction, but when the quicklime is in contact with the moisture of the soft ground and sludge, it becomes hydrated by the exothermic reaction during hydration at room temperature. Insoluble compounds form CSH.

At this time, less than 30 parts by weight of fly ash does not react completely with quicklime (which is calcified) absorbing moisture from soft ground and sludge, and thus cannot produce insoluble compounds. Will occur.

Therefore, in the present invention, the fly ash is preferably made of 30 to 60 parts by weight.

<Blast furnace slag>

The blast furnace chain slag in the present invention is Melilite (2CaO Al ₂ O ₃ SiO ₂ Since 2CaO MgO 2SiO ₂ ) is used, the ratio of vitrification of the blast furnace slag in the present invention is preferably 95% or more since the glass has high glass ratio and high hydration property.

Therefore, the quicklime in the blast furnace slag is made of vitrified amorphous material (amorphous), and since it is not hydrophobic by itself, it is added to anhydrous gypsum as a stimulant to promote initial strength improvement and activation of long-term strength by latent hydrophobic. If it is less than the long-term strength expression is lower than 40 parts by weight, the initial curing rate is delayed due to the latent hydraulic properties of the slag, there is a problem that the solidification and stabilizing effect of heavy metals and the like contained in the soft ground and sludge occurs.

Therefore, in the present invention, the blast furnace chain slag is preferably made of 10 to 40 parts by weight.

Quicklime

In the present invention, the quicklime is more than 90% purity and the powder is preferably made of 5 to 20 parts by weight of 4,000 cm 2 / gr or more, because the quicklime is in contact with water sludge due to water reduction and expansion due to exothermic reaction during hydration Curing is performed smoothly by air entrainment.

At this time, if the quicklime is less than 5 parts by weight, it is difficult to remove the moisture content contained in the soft ground and sludge. On the contrary, when it is more than 20 parts by weight, it becomes strong alkali (pH 10 or more), and the ammonium in the soft ground and the sludge is changed into ammonia gas, resulting in odor. Will occur.

In addition, if the purity of quicklime is less than 90%, the amount of quicklime is increased, so that other raw materials are reduced, thereby losing the function of the hardener.

<Anhydrous gypsum>

In the present invention, the anhydrous gypsum is more than 90% purity and is preferably made of 5 to 20 parts by weight of powder more than 5,000 cm 2 / gr, which is less than 5 parts by weight of the initial strength is lowered, on the contrary 20 parts by weight If exceeded, the initial strength may be improved, but the problem of lowering the long-term strength increase occurs.

At this time, when the purity of the anhydrous gypsum is less than 90%, there is a problem that the initial strength and long-term strength is lowered.

<Alumni>

In the present invention, the gimbal plaque serves as an accelerator for further activating the initial strength of the anhydrite and the production of ethrinite, and less than 5 parts by weight compared to 100 parts by weight of anhydrous gypsum may serve as a stimulant. If it is more than 15 parts by weight, it has a disadvantage in that it causes a relatively trouble in the strength development of anhydrous gypsum.

Therefore, in the present invention, it is preferable that the alum alum consists of 5 to 15 parts by weight relative to 100 parts by weight of anhydrous gypsum.

<Cement>

In the present invention, the cement (portland cement) is {trilimic acid silica (3CaO.SiO ₂ ), silicic acid lime (2CaO.SiO ₂ ), alumina trioxide (3CaO.Al ₂ O ₃ ), iron aluminic acid 4 lime ( 4CaO.Al ₂ O ₃ .Fe ₂ O ₃ )} The composition reacts with the moisture of the soft ground and sludge to harden.

At this time, the produced lime becomes CSH hydrate by silica and pozzolanic reaction, and cement is strong alkali, so when mixed more than 40 parts by weight, ammonium in soft ground and sludge is transformed into ammonia gas and odor is generated. Has a problem that the curing rate is slowed due to a decrease in the pozzolanic reaction.

Therefore, in the present invention, the cement is preferably made of 10 to 40 parts by weight.

In addition, although cement is the main component of cement like quicklime, silica, alumina, and iron are combined with each other.

Tricalcium silicate (3CaO.SiO ₂ ) → It makes initial strength high and the heat of hydration is high, so the underwater expansion is large,

Silicate 2 lime (2CaO.SiO ₂ ) → Contribution to late strength, low heat of hydration, condensation proceeds slowly,

Tricalcium aluminate (3CaO.Al ₂ O ₃ ) → Fast initial condensation, severe shrinkage, weak resistance to seawater or sewage,

Tetralimate of iron aluminate (4CaO.Al ₂ O ₃ .Fe ₂ O ₃ ) → Fast hydration but little contribution to strength and high resistance to sulfur content.

This will be described in more detail as follows.

The solidification composition for treating soft ground and sludge treatment using the industrial waste of the present invention, unlike the existing solidifying agent, prepares the solidifying agent using industrial wastes. Surface area: 2,800㎠ / gr ~ 3,200㎠ / gr) The production of ethrinite is low, so the cement and anhydrous gypsum are mixed and pulverized between 4,000cm2 / gr ~ 5,000cm2 / gr to promote high reactivity. In addition, fly ash or blast furnace slag, which is an industrial waste, is not hydrophobic in itself, but accelerates the hydration reaction of ethrinzite due to the cement, anhydrous gypsum, and other stimulants to improve initial and long-term strength.

Chemical composition of the composition in the present invention is shown in Table 1.

As shown in Table 1, the present invention made of a combination of the composition is a variety of sludge generated when treating the sewage by adding a fly ash or blast furnace slag without the hydraulic composition itself, calcium oxide, cement and anhydrous gypsum (main component of quicklime) Sludge) or industrial waste sludge and other reclaimed land or soft ground improvement, etc. Widely applied, and reacts with them rapidly to reduce the moisture and increase the initial strength by blast furnace slag, which is influenced to long-term strength by heavy gypsum. It does not contaminate soil or ground water by forming a stable hardened body by reacting with sludge in a short time so as not to elute.

In particular, the present invention consists of main components such as SiO ₂ (silicon oxide), CaO (calcium oxide), Al ₂ O ₃ (aluminum oxide), sulfuric anhydride (SO ₃ ), and other traces of Fe ₂ O ₃ (iron oxide). It is composed of elements.

When the above components react with the moisture of the soil of various sludges or reclaimed land

Solidified objects such as sludge + CaO → calcined lime (Ca (OH) ₂ )

CaO + H ₂ O → Ca (OH) ₂

56.08 + 18 → 74.08

 1g + 0.32g → 1.32g

As indicated above, 1 g of quicklime requires 0.32 g of water.

Al ₂ O ₃ nSiO ₂ → Alm (OH) n SimOn polymerization

The aluminum or soluble silicate has an ion exchange capacity and a positive exchange capacity with an anion in an acidic region with a cation and an alkaline region.

In addition, aluminum or soluble silicates usually contain mineral trace elements and elute in water to act as a catalyst. Mineral trace elements, on the other hand, act as an oxidation catalyst, adsorb with dissolved metals, and convert water-soluble organics into insoluble materials.

Al ₂ O ₃ → Al ₂ (OH) ₃ + Alm (OH) n → polycondensation aluminum hydroxide

As described above, the aluminum oxide becomes colloidal aluminum hydroxide and polycondensation aluminum (ionization), and the suspended suspension promotes the potential charge between particles to disintegrate and atomize the particles to form hydrophobic aggregates.

Further, the cement contained in the lime silicate 3 (3CaO.SiO _2), 2-lime silicate (2CaO.SiO _2), 3-lime aluminate (3CaO.Al ₂ O _3), iron aluminate 4 Lime (4CaO.Al ₂ O ₃ .Fe ₂ O _{3 )} and anhydrous gypsum (CaSO ₄ ) act as a mineral called ethrinzite (3CaOAl ₂ O ₃ 3CaSO ₄ 32H ₂ O) to bind as an effective substance for coagulation control and solidification of harmful heavy metals.

As described above, in the present invention, the hydration reaction is advanced by moisture contained in various sludges and solidification objects, and the chemical reactions such as the production of a large amount of lime sulfoaluminate with hydraulicity by the silicate lime hydrate of cement That is, it acts effectively as sludge or ground stabilizer by solidifying by pozzolanic reaction.

In addition, as mentioned above, as mentioned above, the softener for treating the soft ground and the sludge requires a large amount of water during the hydration reaction. Therefore, a large amount of water is absorbed from the solidification object to cause a solidification effect, thereby increasing the dehydration effect of the solidification object.

Therefore, the present invention includes a fly ash or blast furnace slag that does not have its own hydraulic properties, including calcium oxide, cement, anhydrous gypsum, which are the main components of quicklime, and reacts quickly to sludge or soft ground to reduce moisture and to anhydrous gypsum. By improving the initial strength as well as the long-term strength by the blast furnace slag, it reacts with the sludge in a short time so as not to elute the heavy metals mixed in the hazardous waste to form a stable hardening body to prevent contamination of the soil or groundwater in advance. Done.

As described above, the embodiment of the present invention has been described in detail, but the scope of the present invention is not limited thereto, and it is natural that the scope of the present invention is included in the scope of the present invention up to the configuration substantially equivalent to the embodiment of the present invention. something to do.

The present invention crushes fly ash and blast furnace slag and industrial limes, quicklime, anhydrous gypsum, cement, etc. to have a certain powder degree to increase the unit surface area to quickly activate the production of ethrinite to solidify the soft ground or sludge Has the advantage of promoting.

In addition, the present invention has the advantage of preventing the contamination of the soil and ground water due to heavy metals discharged from the sludge by solidifying the soft ground or sludge quickly.

In particular, the present invention is a very useful invention that can generate economic benefits by recycling fly ash and blast furnace slag, which was classified as industrial waste, as a high value-added resource.

Claims (1)

In the solidifying agent composition for soft ground and sludge treatment to accelerate the solidification action by grinding fly ash, blast furnace slag and quicklime, anhydrous gypsum, cement, rock cover, etc. The fly ash is 30 to 60 parts by weight of the powder degree of 4,000 cm 2 / gr or more, the blast furnace slag is 10 to 40 parts by weight of the powder degree of 4,000 ~ 6,000 cm 2 / gr, the quicklime is more than 90% purity and the powder is 4,000 cm 2 / 5-20 parts by weight or more of gr, the anhydrous gypsum has a purity of 90% or more, 5-20 parts by weight of powder of 5,000 cm 2 / gr or more, the cement is 10-40 parts by weight of powder of 4,000-5,000 cm 2 / gr, the girly Alum is a soft ground and sludge treatment solidifying composition using industrial waste, characterized in that it comprises 5 to 15 parts by weight relative to 100 parts by weight of anhydrous gypsum.