KR100415178B1 - A Liner for waste disposal using Powdered Feldspar and the method therefor - Google Patents

Abstract

PURPOSE: Provided is a waterproof liner, which uses powdered feldspar and thus is economically favorable and environmental-friendly, and prevents the diffusion of pollution materials. CONSTITUTION: The waterproof liner is formed by the method comprising the steps of: screening powdered feldspar; screening actual sandy earth based on smectite and montmorillonite; mixing bentonite thereto in various weight ratios, tamping the mixture and preparing multiple standard sieves; performing water permeation tests using the standard sieves; determining the optimum weight ratio of the bentonite based on the weight of the powdered feldspar from the sieve showing the highest water permeability; mixing powdered feldspar, bentonite and actual sandy earth, in various weight ratios of the powdered feldspar, based on the optimum weight ratio of the bentonite, tamping the mixture and preparing multiple standard sieves; performing water permeation tests using the standard sieves; determining the optimum weight ratio of the powdered feldspar based on the actual sandy earth; and forming a waterproof liner using the optimum weight ratio among the powdered feldspar, bentonite and actual sandy earth.

Description

A liner for waste disposal using Powdered Feldspar and the method therefor}

In the case of landfill facilities among domestic waste treatment facilities, about 300 landfill facilities are constructed and operated in accordance with the regulations of the Waste Management Act.The main functions of landfill facilities are divided into storage functions, treatment functions, and order functions. In this case, it is prescribed to form a civil synthetic resin liner to prevent leakage of leachate in landfills and a lining layer having a degree function in the lower part.

In the case of the bottom layer of civil synthetic resin liner which has such ordering function, it is possible to prevent the spread of pollution by reducing the hydraulic movement of pollutants in general, and also to have the adsorption ability of heavy metals, thereby spreading soil pollution. Prevents the function.

Currently applied technologies are liners made by mixing clay or clay materials and liners made by mixing solidifying agent, bentonite, cement, etc. as additives to improve ordering function. The liner method has been developed and applied to improve the self-purifying function in the layer during the penetration of contaminants. First of all, in the method of using clay, there is a lack of high quality clay which is used as a material and there are many difficulties in construction.

Such additives can improve the function, but they act as a factor in increasing site conditions or construction costs, and there is a need for the development of simple and inexpensive methods because of the secondary pollution of the pollutants caused by the additives.

Under the Waste Management Act, in the case of the lower barrier layer of the landfill facility, the clay under the civil synthetic resin liner is ground with clay and clay mineral mixed soil, and the permeability coefficient is less than 10 millionths per second and the thickness is more than 50 centimeters. In this case, it is prescribed to install a liner of 1 meter or more).

On the other hand, aggregates used in domestic construction are gravel (crushed aggregate) and sand. According to the Ministry of Construction and Transportation (2002, first quarter), the collection of such aggregates is collected from rivers, seas, forests and land. In the case of sand, the production rate of river aggregate, sea aggregate and land aggregate source is about 96.2% (12,514 thousand㎥), and sand production in forest is very low, while in the case of crushed aggregate, it is only 97 in forest aggregate source. It is a situation that produces% (11,276 thousand ㎥), waste stone generated during the production of such crushed aggregate is 25 ~ 45%, the average 35%. In the first quarter of 2002, the amount of waste-rock powder is 3,946,600㎥ and the average annual amount of 15,780 thousand㎥ is generated.

Aggregates are produced by 1,384 companies in Korea, but pure forest aggregates are collected by 387 companies nationwide, indicating that the number of firms is small while aggregate aggregates are high. Aggregates are produced by blasting, crushing, and crushing, and the amount of waste stone generated during this process is very large, and each aggregate source is piled up due to the lack of special accommodation or recycling. It's being processed.

Therefore, in the present invention, by using waste stone powder (廢 石粉, Powdered Feldspar) generated when the aggregate is collected, there is an excellent effect in terms of economics and recycling of the construction cost reduction effect of the landfill facility.

On the other hand, since the concept of sanitary landfill is introduced, the research on the type, thickness, size, etc. of the bottom order layer of the domestic landfill has been progressed, and recently, research on the landfill material mixed with bentonite has been actively conducted.

For example, a study on the permeability characteristics of bentonite and clay order materials, a study on the permeability characteristics of soil-bentonite mixed soils, and the analysis of the material characteristics of granite and sand mixed with bentonite Study of applicability, permeability and strength characteristics of clay-bentonite mixtures.

Based on the results of the permeation function, the bentonite content ratio was 7% or more when the soil was clay sand (SC) or organic clay (OL) according to the degree of bentonite swelling. In the case of SC), more than 10% to 15% met the permeation standard. However, the permeability coefficient was slightly different according to the degree of swelling of bentonite, but more than 7% satisfied the permeability criteria. In addition, the permeability coefficient of pure soil soil (SM) soil without bentonite addition was 2.94 × 10 ^-5 ~ 7.22 × 10 ^-7 ㎝ / sec, which did not satisfy the permeability standard. It can be seen that the water permeability coefficient is different depending on the content ratio of the components exhibiting the order-order function.

However, most of the above studies were limited to studies on the degree of beneficiation, strength and adsorption, and the behavior of ground environmental pollutants according to bentonite swelling degree by selecting various soils as bentonite and field soil.

Moreover, in the past, there have been no reports on the use of waste-rock powder as an ordering material, which has to be disposed of at a separate cost.

In the present invention, it is possible to recycle wastes by considering the function and physical and chemical reactions of the bentonite, waste-rock powder and field soils based on the permeation standards prescribed in the Waste Management Act, and the economic feasibility of constructing landfills. It is an object of the present invention to provide a repellent material layer and a method for manufacturing the same.

1 is an experimental graph showing the relationship between the dry density and the moisture content according to the compacted waste-rock content.

2 is an experimental graph showing the relationship between the maximum dry density and the optimum function ratio for each bentonite content.

3 is an experimental graph showing a change in permeability coefficient for each bentonite content.

Figure 4 is an experimental graph showing the change in uniaxial compressive strength according to the age of age.

5 is an experimental graph showing the change in dry density and moisture content according to the mixing ratio.

6 is an experimental graph showing a change in permeability coefficient according to the blending ratio.

7 is an experimental graph showing the change in uniaxial compressive strength according to the number of days of age.

In order to achieve the above object, a method for manufacturing a waste layer for waste treatment according to the present invention is configured as follows.

In other words, in the method of manufacturing a wastewater treatment material layer for preventing the spread of pollution by reducing the hydraulic movement of the pollutants, and preventing the spread of soil through the adsorption function,

Sifting powdered feldspar (Powdered Feldspar) generated when collecting the aggregate to form a powder having a predetermined particle size or less,

Sifting the soil soil of the sandy soil series (SM) and preparing it in powder form having a predetermined particle size or less;

Preparing a plurality of specimens after the compaction process by mixing bentonite in various weight ratios (wt.%) With respect to the waste-rock powder,

Permeability test for measuring the permeability coefficient of the prepared specimens satisfies the value below the standard permeability coefficient (e.g. 1 × 10 ^-7 cm / sec) determined by the relevant method (e.g. waste management method). Checking whether or not

Determining an optimum bentonite weight ratio (wt.%) For the waste-rock powder from the specimen having the best permeability according to the above-mentioned result;

Mix waste stone powder, bentonite, and spot soil, but the amount of bentonite is fixed by mixing the optimum bentonite weight ratio with respect to the total mixed sample, and then compacted by mixing waste stone powder in various weight ratios (wt.%) To spot soil. After the production of a plurality of specimens,

Permeability test for measuring the permeability coefficient of the prepared specimens satisfies the value below the standard permeability coefficient (e.g. 1 × 10 ^-7 cm / sec) determined by the relevant method (e.g. waste management method). Checking whether or not

Determining an optimum weight ratio (wt.%) Of waste stone to the soil from the specimen having the best permeability characteristics according to the above confirmation result;

It characterized in that it comprises the step of producing a filler layer by mixing the waste-rock powder, bentonite, spot soil according to the determined optimum waste-rock powder weight ratio, the optimum bentonite weight ratio.

At this time, the waste-rock powder is preferably sifted using a sieve having a sieve number 4.

In addition, it is preferable that the determined optimum waste-rock weight ratio is 10 to 50 weight ratio, in particular 10 weight ratio or more preferably 30 weight ratio.

In addition, the optimum bentonite weight ratio is preferably 3 weight ratio.

On the other hand, the degree of waste disposal layer according to the present invention comprises the following components.

In other words, in order to reduce the hydraulic movement of the pollutants to prevent the spread of pollution, and in the waste water treatment layer for preventing the spread of soil through the adsorption function,

The waste stone powder (Powdered Feldspar) generated when collecting the aggregate is made into a powder form of a predetermined particle size or less, waste stone powder having a weight ratio of 10 to 50 with respect to the whole,

Bentonite having a weight ratio of 3 to the whole,

The sieve is made into a powder form of a predetermined particle size or less, and is made of a mixed clay of sandy soil series (SM) having the remaining weight ratio based on 100 weight ratio.

At this time, the weight ratio of the waste-rock powder is more preferably 10 weight ratio or 30 weight ratio.

Hereinafter, the present invention will be described in detail with reference to the method of manufacturing the order layer according to the present invention.

The method of manufacturing the order layer according to the present invention was largely divided into two steps.

[Step 1]

; As a preliminary test for verifying the order effect of waste-rock powder, bentonite is mixed with waste-rock powder on a certain content basis to prepare specimens and permeation tests, and the standard water permeability coefficient of 1 × 10 ^-7 cm We tried to find the optimum waste-rock content based on the constant bentonite that is less than / sec.

For this purpose, first, in the present invention, on-site soil of sandy soil series (SM) was used. The permeability coefficient of the same sandy soil type (SM) in the soil classification without adding bentonite is 2.94 × 10 ^-5 to 7.22 × 10 ^-7 cm / sec, which does not satisfy the permeability standard, and can exhibit the degree of function even if the soil classification is the same. It is judged that the permeability coefficient is different according to the content of silty component. The permeability coefficient of the field soil used in the present invention is 3.60 × 10 ⁻⁶ cm / sec, which represents the median value of the existing research results.

Since pure sandy soils do not meet the permeability standards, there are many similar studies to add bentonite to meet the permeability standards, and even when the bentonite content ratio is 7% or more in the case of clay sands similar to sandy soils, Although the permeability criterion was generally satisfied, the swelling degree of the mixed bentonite should be considered. Therefore, the experiment was divided into three cases as shown in Table 1. (Compared to the order function for mixing bentonite content of 5%, 3%, and 1% or less, based on waste-rock powder, 7% or less)

To do this, the following steps were taken:

One). Bentonite powder, waste-rock powder or field soils were mixed in a certain amount by the number of cases, and for the experiment, the sample was mixed with only the sample sifted with No. 4 (4.75 mm).

2) Specimens were prepared by mixing on-site soil and waste-rock powder with bentonite powder, respectively. In the present invention, it was compacted with equipment of the outer diameter 5cm, height 10cm, rammer weight 1.5kg of specially prepared compaction mold.

3) Triaxial compressive wall test as defined by EPA, which shows the relationship between time and water level enhancement that occurs when penetrating a sample with a constant diameter and length to measure the permeability coefficient of the sample according to the mixing ratio. Permeability coefficient was measured by (ASTM D5804).

4) The uniaxial compressive strength was measured for each aging age according to the content of waste-rock powder and soil.

5) In order to observe the pozzolanic reaction between silicate, aluminate and calcium (Ca) contained in the waste-rock powder and bentonite, the particle shape and surface of the waste-rock powder, bentonite and The change of particle shape of waste stone and bentonite before and after saturation of the mixed specimens were observed.

1 to 4 are experimental results, Figure 1 is an experimental graph showing the relationship between the dry density and moisture content according to the compacted waste-rock content, Figure 2 is an experiment showing the relationship between the maximum dry density and the optimum water content ratio by bentonite content 3 is an experimental graph showing a change in permeability coefficient for each bentonite content rate, and FIG. 4 is an experimental graph showing a change in uniaxial compressive strength according to age of age.

From the above test results, it can be seen that the permeability coefficient of the sample mixed with bentonite 3% by weight and 5% by weight of the waste-rock powder satisfies the standard value prescribed by the Waste Management Act, and it is preferable to use expensive bentonite as little as possible. It can be seen that it is more preferable to mix bentonite with 3% by weight of the waste-rock powder.

[Second step]

According to the results of the first stage experiment, the bentonite was fixed to 3% by weight of waste rock powder, and then mixed with waste stone powder and spot soil at a varying ratio, and the degree of function and strength were tested as in the first stage. For the experiment, the experiment was divided into six cases as shown in Table 2.

5 to 7 are experimental results, Figure 5 is an experimental graph showing the change in dry density and moisture content according to the mixing ratio, Figure 6 is an experimental graph showing the change of permeability coefficient according to the mixing ratio, Figure 7 is the number of days Experimental graph showing uniaxial compressive strength change.

From the above experimental results, it was found that when the bentonite was fixed to 3% by weight of waste-rock powder, the permeability coefficient of the sample containing 10 to 50% by weight of waste-rock powder satisfies the standard value prescribed by the Waste Management Act. It is preferable to use as little as possible, particularly expensive bentonite (30% by weight is the best), it can be seen that a mixture of 3% by weight of bentonite, 10% by weight of waste-rock powder is more preferred.

The wastewater treatment layer according to the present invention has an economical and environmentally-friendly advantage of utilizing waste stone powder that can only be disposed of at a separate cost in the past, and reduces the bentonite content, which is expensive compared to conventional layers of material. This is very advantageous in terms of cost reduction.

Despite such economical and environmentally friendly advantages, the wastewater treatment layer according to the present invention prevents the spread of pollution by reducing the hydraulic movement of pollutants compared to the conventional orderly layers, and prevents the spread of soil contamination through the adsorption function. The inherent function of preventing the lining layer is excellent.

Claims (8)

In the method of manufacturing the wastewater treatment layer for reducing the spread of the contaminants to prevent the spread of pollution, and preventing the spread of soil through the adsorption function, Sifting the powdered feldspar (Powdered Feldspar) generated when the aggregate is collected in a powder form having a predetermined particle size or less; and Sifting the clay soil of the sandy soil series (SM) to prepare a powder form having a predetermined particle size or less; Preparing a plurality of specimens after the compaction process by mixing bentonite at various weight ratios (wt.%) With respect to the waste-rock powder; Permeability test for measuring the permeability coefficient of the prepared specimens satisfies the value below the standard permeability coefficient (e.g. 1 × 10 ^-7 cm / sec) determined by the relevant method (e.g. waste management method). Checking whether or not; Determining an optimum bentonite weight ratio (wt.%) For the waste-rock powder from the specimen having the best permeability characteristics according to the confirmation result; Mix waste stone powder, bentonite, and spot soil, but the amount of bentonite is fixed by mixing the optimum bentonite weight ratio with respect to the total mixed sample, and then compacted by mixing waste stone powder in various weight ratios (wt.%) To spot soil. Manufacturing a plurality of specimens after the treatment; Permeability test for measuring the permeability coefficient of the prepared specimens satisfies the value below the standard permeability coefficient (e.g. 1 × 10 ^-7 cm / sec) determined by the relevant method (e.g. waste management method). Checking whether or not; Determining an optimum waste stone weight ratio (wt.%) For the soil from the specimen having the best permeability according to the result of the check; Forming a repellent material layer for waste treatment using the waste-rock powder, characterized in that it comprises the step of mixing the waste-rock powder, bentonite, spot soil according to the determined optimum waste-rock powder weight ratio, the optimum bentonite weight ratio Way. The method of claim 1, wherein the waste-rock powder is sieved using a sieve having a sieve number 4. The method according to any one of claims 1 to 3, wherein the determined optimum waste stone weight ratio is 10 to 50 weight ratio. 4. The method of claim 3, wherein the optimal bentonite weight ratio is 3 weight ratios. The method of claim 4, wherein the determined weight ratio of the waste-rock powder is 10 weight ratio. The method of claim 4, wherein the determined weight ratio of the waste-rock powder is 30 weight ratio. In order to prevent the spread of pollution by reducing the hydraulic movement of pollutants, and in the degree of waste disposal for waste treatment to prevent the spread of soil through the adsorption function, Wasted powder produced during the collection of aggregates (Powdered Feldspar) is sieved to make a powder of a predetermined particle size or less, waste stone powder having a weight ratio of 10 to 50 to the total; and Bentonite having a weight ratio of 3 to the total; The sieve is made in a powder form of a predetermined particle size or less, on-site soil of the sandy soil series (SM) having the remaining weight ratio based on 100 weight ratio; characterized in that the mixture is made, waste material for waste treatment using waste stone powder layer. According to claim 7, wherein the weight ratio of the waste-rock powder is characterized in that the weight ratio of 10 or 30 weight ratio, the order layer for waste treatment using waste-rock powder.