KR100469040B1 - A Method for construction of Waste landfills - Google Patents

Abstract

The present invention relates to a method for constructing a waste landfill, and more particularly, to a method for constructing a landfill in which wastewater is formed by blocking the outflow of leachate by the bentospray method.

The present invention for this purpose, after digging the landfill site, to form a groundwater exclusion layer including rubble and perforated pipes, and the order layer by the bentospray method of spraying bentonite and adhesive at the same time on top of the groundwater exclusion layer And a step of forming a protective earth layer on top of the order layer, in particular, after installing a high density polyethylene (HDPE) film on top of the groundwater exclusion layer, the high density polyethylene film by the bentospray method. It is preferable to form a degree layer on the upper part and to install a polyethylene (PE) film on the upper part of the degree layer. In order to form the order layer, it is more preferable to spray bentonite and the adhesive such that the order thickness of the order layer is 6 to 9 mm.

Description

A method for construction of waste landfills

The present invention relates to a method for constructing a waste landfill, and more particularly, to a method for constructing a landfill in which wastewater is formed by blocking the outflow of leachate by the bentospray method.

Recently, as interest in environmental pollution has increased, disposal of waste has become a major social problem among the causes of environmental pollution, and methods of incineration or landfill have been used for disposal of such waste. However, in the incineration method, there was a problem of causing air pollution due to the dust generated during incineration, and in the case of the landfill method, there was a problem of pollution of soil, river, river, etc. due to selection of landfill and leachate generated from landfill. .

Therefore, in the case of the landfill method, construction methods of landfills for preventing the outflow of leachate generated from wastes have been developed, and cross-sectional views of landfills constructed by conventional waste landfill construction methods are shown in FIGS. 1 to 4. Generally, the landfill of the waste to be constructed is processed using a cage-type landfilling method which proceeds to excavation in a normal or under-strait type and embeds the waste where it is excavated. In forming a water repellent facility at the bottom of the landfill, as shown in FIG. By simply stacking the groundwater exclusion layer 11, the clay order layer 12a, and the protective soil layer 13 sequentially on the ground 10, or as a complementary method, as shown in FIG. 2, the clay order layer ( A method of laying a high density polyethylene (HDPE) film (12b) on 12a), or using a mixed order layer (12c) mixed with soil and bentonite instead of a clay order layer (12a) as shown in FIG. As shown in Fig. 4, there is a method of forming bentonite sheet 12d having bentonite interposed between the permeable sheets as an order layer.

However, the order by the clay order layer 12a simply requires that the clay order layer 12a be formed to a thickness of about 1000 mm. In this case, a lot of time and money are required to obtain a large amount of clay, and the order wall is formed on the slope of the landfill. When formed, the clay order layer 12a, the mixed order layer 12c, and the like are not fixed to the landfill slope, and in general, such ordering facilities are rarely used. In addition, when the high density polyethylene film 12b is used, since most of the landfills are soft grounds having poor ground and soil properties, since the bearing capacity of the lower clay layer is insufficient, floating settlement occurs, so that the bonding portions between the high density polyethylene (12b) sheets Not only was it frequently damaged, but also the damage of the film 12b itself due to construction equipment or the like during construction or after construction resulted in a problem that the degree of leachate generated from waste was not perfect. In addition to the high-density polyethylene film 12b, as well as the bentonite mat 12d to be installed on the bottom surface or the inclined surface of a wide landfill, several mats 12d must be joined or connected to each other so that a joint portion or a joint portion is generated. In these joints or joints, there is a problem that leachate flows out due to inadequate installation or damage to use, floating settlement of the ground, etc., especially in the case of irregular ground surface, it is difficult to install, and in case of leaking It was difficult, and the maintenance range was large, and the maintenance cost was high.

The present invention forms a waste layer without joints or seams in the inner layer, which causes problems in the conventional landfill, and also facilitates the construction and repair of the waste layer, as well as construction of a waste landfill that is stably adhered to the construction surface. To provide a way.

To this end, a method of constructing a waste landfill site of the present invention comprises the steps of forming a groundwater exclusion layer including a rubble and a perforated pipe after digging a landfill site, and simultaneously applying bentonite and an adhesive by a bentospray method on the groundwater exclusion layer. Spraying but allowing the adhesive to bond before the bentonite to form an ordered layer to stably bond between the groundwater exclusion layer and the bentonite, and forming a protective earth layer on top of the ordered layer. In the bentospray method, it is preferable that the bentonite powder and the adhesive have a weight ratio of 5 to 12: 1 and are sprayed simultaneously on the groundwater exclusion layer, and bentonite is 10 to 18 mesh. In the bentospray method, 70 to 95 wt% of sand may be mixed with bentonite, or 8 to 20 wt% of zeolite powder may be mixed.

In addition, the bentospray method uses 10 to 20% by weight of a water-soluble neutral adhesive, 1.5 to 2.0% by weight of ammonia, 0.8 to 1.0% by weight of ethyl alcohol, 0.5 to 0.8% by weight of glycerin, 0.06% by weight of yeast, and 20 to 80% by weight of water. 35 to 60 wt% of polymer or latex, 0.7 to 2.0 wt% of suspension (cellulose gum), 0.15 to 8.0 wt% of carbohydrate (starch or starch), 0.8 to 1.0 wt% of ammonia, 0.8% biodegradable anion soap Use an adhesive comprising from -5.0% by weight, 0.06% by yeast, up to 35% by weight of water, 30-68% by weight of asphalt emulsion, 0.5-1.2% by weight of emulsion, 0.5-4.0% by weight of other additives, water 30-70 An adhesive comprising a weight percent is used.

In the forming of the order layer, after the high density polyethylene (HDPE) film is installed on the groundwater exclusion layer, the order layer is formed on the high density polyethylene film by the bentospray method and the order layer is formed by the bentospray method. After that, it is preferable to install a polyethylene (PE) film on top of the order layer, and in particular, it is more preferable to spray bentonite and adhesive so that the dry thickness of the order layer is 6 to 9 mm.

1 to 4 are cross-sectional views of the bottom surface of a conventional landfill.

5 is a cross-sectional view of a waste landfill constructed in accordance with the present invention.

Figure 6 is a schematic perspective view of a spray gun for the ventospray method of the present invention.

7 is a cross-sectional view of a waste landfill in the process of forming a degree layer according to the present invention.

Explanation of symbols on the main parts of the drawings

100: base 110: bottom surface

120: slope 111, 121: groundwater exclusion layer

112, 122: high density polyethylene (H.D.P.E) film 113, 123: order layer

113a: order layer 114, 124 being formed: polyethylene (P.E) film

115, 125: protective soil layer 200: spray gun

210: bentonite spray gun 211: bentonite hose

212: bentonite 220: adhesive spray gun

221: adhesive hose 222: adhesive

Hereinafter, with reference to the accompanying drawings will be described in detail an embodiment of the present invention.

First, as shown in FIG. 5, the landfill site is excavated in the area where the waste is to be landfilled, and then, the groundwater existing in the periphery of the landfill is prevented from flowing into the interior of the landfill. Groundwater exclusion layers 111 and 121 are formed by using perforated pipes and rubble.

In addition, bentonite and an adhesive are formed on the construction surface to form order layers 113 and 123 on the groundwater exclusion layers 111 and 121 to prevent leachate generated in the landfill from leaking out to the bottom or slope of the landfill. Construct using the spray spraying bento spray method.

The bentospray method is a process of forming bentonite on the spot with a specially prepared adhesive to form a layer.

In order to spray bentonite and adhesive on the upper portion of the groundwater exclusion layer 111 and 121, first, the bentonite to be sprayed by minimizing protrusions, holes, irregularities and the like by compacting the upper surface of the groundwater exclusion layer 111 and 121 and Minimize the consumption of adhesive. After the compaction of the upper surfaces of the groundwater exclusion layers 111 and 121 is finished, bentonite and a specially prepared adhesive are simultaneously sprayed on the upper surfaces of the groundwater exclusion layers 111 and 121. . That is, as shown in Figure 6, by the bentonite spreading gun 210 connected to the bentonite hose 211 and the adhesive spraying gun 220 connected to the adhesive hose 221 in close proximity at the same time, the bentonite spreading gun 210 The adhesive 222 sprayed from the adhesive spray gun 220 positioned below is first adhered to the construction surface, and the bentonite 212 is adhered to the upper portion of the adhesive 222 adhered to the construction surface first. ) Is stably bonded to the construction surface. At this time, it is preferable that the weight ratio of bentonite 212 and the adhesive 222 to be sprayed on the construction surface is adjusted to be 5-12: 1.

Bentonite absorbs water and expands to about 10 to 20 times its volume, and when dried, water is discharged to shrink back to its original volume, and this expansion and contraction can be repeated indefinitely, and bentonite is chemically stable as an inorganic substance. Therefore, it can be used continuously as a waterproof material for a long time. However, even bentonite with such waterproof properties may turn into the worst system if the application is not suitable and the construction conditions are inadequate.

Therefore, in the present invention, bentonite having 10 to 18 mesh is used so that the waterproofing property of bentonite is most effectively exhibited. The bentonite may be mixed with 70 to 95% by weight of sand or 8 to 20% by weight of zeolite.

When the bentonite is pulverized into 10 to 18 mesh as described above, when the particles of bentonite are larger than 10 meshes, the voids between the bentonite particles become excessively large, so that leachate water permeated between the pores may occur, and the bentonite particles may be 18 meshes. If it is smaller than this, the particles become excessively fine particles and may scatter into the air due to the spraying pressure during construction, so that the size is 10 to 18 mesh, which is the most appropriate size. In addition, by mixing the bentonite with sand in the above ratio, when bentonite particles are hydrated evenly mixed between the sand particles, effective waterproofing is possible even without pressure of the upper material, and the material consumption of bentonite can be reduced. have. And, there is a disadvantage in that it is difficult to attach to the construction surface by mixing the sand, but in the landfill is installed on the bottom surface 110, or the construction on the inclined surface 120 rather than the vertical surface, by spraying with an adhesive to be described later Bonding and fixing are sufficiently stable to the construction surface. However, when the mixture of bentonite and sand is not uniform, and only a part of the sand is formed, the leachate penetrates into the pores between the sand particles, so that the leachate may not be blocked. Therefore, the mixture of bentonite and sand should be uniform.

In addition, zeolite is a silicate mineral of aluminum containing alkali metals and alkaline earth metals and containing crystallized water, which has characteristics such as adsorption, hygroscopicity and cation exchangeability, and thus is widely used in various fields such as ion exchangers, wastewater treatment agents, soil improving agents, and the like. It is a mineral used. Therefore, by mixing 8 to 20% by weight of zeolite with bentonite, even if the leachate is not ordered by bentonite but some leachate is leached out, it is purified by the zeolite and flows out, so it is primarily by bentonite. By leaching the leachate and purifying the leachate by the zeolite secondly, the soil contamination by the leachate can be prevented.

In addition, the adhesive used in the bentospray method should be an aqueous adhesive which adheres and maintains bentonite to a predetermined thickness and does not interfere with water to cause hydration of bentonite. In other words, the adhesive should not impair the hydration and expansion of bentonite, it should hold the bentonite in place until the protective layer is formed, and it should be dissolved in water and no harmful components remain. Adhesives for this purpose include 10 to 20% by weight of water-soluble neutral adhesive, 1.5 to 2.0% by weight of ammonia, 0.8 to 1.0% by weight of ethyl alcohol, 0.5 to 0.8% by weight of glycerin, 0.06% by weight of yeast, and 20 to 80% by weight of water. When an adhesive is used, the yeast during the formulation catalyzes the breakdown of the base adhesive into alcohol, the ammonia prevents bentonite from hydrating and swelling too quickly, and the pH after decomposition maintains neutrality. Ethyl alcohol retards fermentation by preventing the growth of bacteria while the adhesive is stored in the tank. Glycerin prevents the viscosity from dropping rapidly until the water is evaporated and backfilled.

Other adhesives include 35 to 60 wt% of polymer or latex, 0.7 to 2.0 wt% of suspension (cellulose gum), 0.15 to 8.0 wt% of carbohydrates (starch or starch), 0.8 to 1.0 wt% of ammonia, 0.8 to 5.0 biodegradable anion soap Adhesives comprising up to 35% by weight, yeast 0.06% by weight, and water up to 35% by weight can be used, wherein the polymer in the formulation uses about 70:30 polymers of butadiene monomer and styrene monomer. The suspension functions to prevent bentonite's water-soluble adhesive from acting on bentonite during construction to cause hydration swelling and uses the cellulose black Sodium carbxy-methyl-cellurose (CMC) used in the suspension. And, soap helps dilute and stabilize the emulsion. This adhesive is used when the protective layer is delayed after the bento spray method is applied or when the bentonite powder is likely to fall off the construction surface due to prolonged exposure to sunlight.

As another adhesive, an adhesive including 30 to 68 wt% of an asphalt emulsion, 0.5 to 1.2 wt% of an emulsion, 0.5 to 4.0 wt% of other additives, and 30 to 70 wt% of water may be used. Particles are used when bentonite is difficult to attach and fix, or when there is high humidity or some snowfall or rainfall is expected. As the asphalt emulsion delays the hydration expansion of bentonite for a long time, the first waterproofing function is taken up by the asphalt layer, and when the water penetrates into the emulsion particles and the bentonite is hydrated and expanded, the bentonite becomes waterproof.

When the bentonite 212 and the adhesive 222 are sprayed on the upper surfaces of the groundwater exclusion layers 111 and 121, when the groundwater or water is likely to flow down on the construction surface, high density polyethylene (HDPE) is applied to the construction surface. It is preferable to spray the bentonite 212 and the adhesive 222 on the film or vinyl sheet, drainage plate, etc., and to adhere and fix the same, and in particular, in order to completely block the leachate, the high density polyethylene (HDPE) film 112, It is more preferable to form the order layer by the bento spray method after the 122 is installed on the groundwater exclusion layers 111 and 121.

When the order layers 113 and 123 are formed by the bentospray method, bentonite and adhesive are sprayed onto the construction surface so that the dry thickness of the order layers 113 and 123 is about 6 to 9 mm, while the order of the leachate is efficiently Excessive consumption of bentonite and adhesives can be reduced.

As described above, by forming the order layer using bentonite by the bentospray method, the construction can be easily performed without being affected by the state of the bottom of the landfill, and as shown in FIG. 7, the bentonite and the adhesive By spraying from the part of the construction surface with the spray gun 200 to form the order layer 113a formed of the bentonite and the adhesive, there is no inevitable joint or joint portion generated in the manner using the sheet or mat, etc. The order layer can be integrally formed in the whole surface of a construction surface. In addition, when the insolvent part of the order layer is found after construction, only the insolvent part may be supplemented by spraying bentonite and an adhesive separately, thereby facilitating repair of the insolvent part after the construction.

After the order layers 113 and 123 are formed on the upper surfaces of the groundwater exclusion layers 111 and 121 by the bento spray method, polyethylene (PE) films 114 and 124 are installed on the upper layers of the order layers 113 and 123. It is desirable to protect the ordered layers 113 and 123 formed of bentonite from excessive moisture and subsequent work.

As described above, after digging in the landfill, the groundwater exclusion layers 111 and 121 are formed, and after the order layers 113 and 123 are formed thereon, the landfill construction process or the landfill after completion of the landfill construction are completed. In order to prevent the collapse of the order layer in order to form a protective soil layer (115, 125) on the upper surface of the order layer or the polyethylene film to a certain thickness or more. The protective earth layers 115 and 125 formed as described above apply pressure to the ordered layers 113 and 123 formed of bentonite, and the bentonite particles forming the ordered layers 113 and 123 may have a predetermined amount due to the sealing pressure of the protective earth layers 115 and 125. After absorbing water, the water absorbing layer no longer absorbs water and forms a gel under pressure, so that the ordering layers 113 and 123 stop further water absorption and expansion and block the leachate, thereby forming the ordering layer 113 formed of bentonite. 123) can more effectively order the leachate.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited to the above-described embodiments, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the claims It belongs to the scope of the present invention.

The present invention, as described above, by forming the order layer by the bento spray method, to form an order layer without the junction portion or joint portion inside the order layer to efficiently order the leachate generated in the landfill, the construction of the order layer and In addition to providing easy maintenance, the method also provided a method for constructing a waste landfill that was stably bonded to the construction surface.

Claims (11)

After digging the landfill site, forming a groundwater exclusion layer including rubble and a perforated pipe; Spraying bentonite and an adhesive at the same time by the bentospray method on top of the groundwater exclusion layer to form the order layer to stably bond between the groundwater exclusion layer and the bentonite by adhering the adhesive to the bentonite before the bentonite; And forming a protective soil layer on top of the order layer. The method of claim 1, The bentospray method is a method for constructing a waste landfill, characterized in that the weight ratio of bentonite and the adhesive is 5 to 12: 1 and sprayed simultaneously on the groundwater exclusion layer. The method of claim 1, The bentospray method is a method of constructing a waste landfill, characterized in that the mixture of the bentonite in the sand 70 to 95% by weight. The method of claim 1, The bentospray method is a method for constructing a waste landfill, characterized in that the bentonite is mixed with 8 to 20% by weight of zeolite. The method of claim 1, The bentospray method is a method for constructing a waste landfill, characterized in that the bentonite is pulverized into 10 to 18 mesh. The method of claim 1, The bentospray method comprises 10 to 20% by weight of a water-soluble neutral adhesive, 1.5 to 2.0% by weight of ammonia, 0.8 to 1.0% by weight of ethyl alcohol, 0.5 to 0.8% by weight of glycerin, 0.06% by weight of yeast, and 20 to 80% by weight of water. A method of constructing a waste landfill characterized by using an adhesive. The method of claim 1, The bentospray method is 35 to 60% by weight of polymer or latex, 0.7 to 2.0% by weight of suspension (cellulose gum), 0.15 to 8.0% by weight of carbohydrate (starch or starch), 0.8 to 1.0% by weight of ammonia, 0.8 to 5.0 biodegradable anion soap A method of constructing a waste landfill comprising the use of an adhesive comprising: by weight, yeast 0.06% by weight, and up to 35% by weight of water. The method of claim 1, The bentospray method is a method for constructing a waste landfill, characterized by using an adhesive comprising 30 to 68% by weight asphalt emulsion, 0.5 to 1.2% by weight emulsion, 0.5 to 4.0% by weight other additives, 30 to 70% by weight water. The method of claim 1, In the forming of the order layer, after installing a high density polyethylene (HDPE) film on the upper portion of the groundwater exclusion layer, a method for constructing a waste landfill is characterized in that the order layer is formed on the high density polyethylene film by the bentospray method. The method of claim 1, In the forming of the order layer, after forming the order layer by the bentospray method, a method of constructing a waste landfill comprising installing a polyethylene (P.E) film on top of the order layer. The method of claim 1, Forming the order layer is a method of constructing a waste landfill, characterized in that to spray the bentonite and adhesive so that the dry thickness of the order layer is 6 to 9 mm.