KR100288578B1 - Sorting and method to purify soil, in the maintenance and restoration of the place reclaimed from rubbish - Google Patents

Abstract

The present invention is to treat the contaminated soil in the landfill and to recycle it as a useful land, digging out the contaminated soil to screen and remove coarse particles and polymer-based waste, screening the particles through a screen to separate the vinyl components by wind power According to the method for purifying contaminated soil of the present invention, the method comprising the step of heating and desorbing the pretreated soil after removal or adjusting the pH and reaction conditions of the pretreated soil and reacting with microorganisms, can not only prevent environmental pollution. However, the treated soil can be recycled into useful land.

Description

Sorting and method to purify soil, in the maintenance and restoration of the place reclaimed from rubbish}

The present invention relates to a method for treating contaminated soil using a thermal desorption process or a biological treatment process.

Various wastes and industrial wastes, which constitute the largest part of the environmental pollution source, are finally landfilled and then moved through various media such as water, soil, and atmosphere, and continue to change and transform, resulting in soil pollution, groundwater pollution, and odors. By affecting natural ecosystems, including humans. However, the damage caused by soil-mediated soil pollution is relatively slower than the damage caused by water quality and air pollution, and the delivery route is complicated. Therefore, the treatment technology has not been established.

Existing techniques for the purification of contaminated soil, for example, in-situ, soil vapor extraction method that extracts contaminants by placing multiple injection holes in the contaminated area and injecting high-temperature steam into the installed injection holes. vapor extraction), soil solidfication to solidify contaminated soil by injecting a solidifying agent into the contaminated soil injection hole, and bioremediation to decompose organic pollutants by locally injecting microorganisms and nutrients into the injection hole. ), Incineration treatment, which incinerators directly incinerate contaminants. However, in Korea, there is a lack of knowledge and experience in soil environment purification technology, and the development of treatment technology is still insufficient. In the foreign countries, the physical / chemical treatment technology field is relatively developed and is in the application stage. The field of in-situ bioremediation has been actively researched since the 1970s and is in its application stage.

Accordingly, the present inventors stabilized the contaminated soils of about 1000 poor landfill sites that are left in Korea by using thermal desorption or biological treatment techniques, which are novel and advanced compared to the existing technologies, and recycle them (sports facilities, parking lots, flower gardens, barns, farmland). The present invention was completed by developing a technology that can be used.

It is an object of the present invention to provide a method for stabilizing contaminated soil in a landfill and treating it to a recyclable level, and a sorting device used therein.

1 is a flow chart of the waste sorting and stabilization method of the soil of the present invention,

2 is a schematic diagram of an example of a sorting apparatus used in the present invention,

3 is a schematic diagram of one example of a bioreactor used in the present invention.

<Description of the symbols for the main parts of the drawings>

10: rotary sorter drum 11: screen

12: rotary gear 13: reducer

14: heating burner 1 15: heating burner 2

16: Inlet 17: Conveyor

18: guide plate 19: blower discharge hood

100 bioreactor drum 101 temperature controller

102: rotary regulator 103: ceramic heater

104: acid substrate 105: strain injection port

106: exhaust gas line 107: blower

108: flow meter 109: filter

110: washing machine 111: adsorption filtration tower

112: contaminated soil

In order to achieve the above object, in one aspect of the present invention (1) the step of excavating the contaminated soil in the landfill to remove coarse particles and polymer-based waste; (2) separating the contaminated soil by passing it through a screen and drying in wind to separate the vinyl component; And (3) provides a method for the purification of contaminated soil comprising the step of heat desorption by heating the treated soil to 150 to 350 ℃.

In another aspect of the present invention, the microorganisms are added to the soil by adjusting the pH of the pretreated soil to 7 to 8, the temperature to 30 to 50 ° C. and the humidity to 40 to 50% as step (3). It provides a method comprising the step of decomposing and removing contaminating organic material.

In order to achieve another object of the present invention, in the present invention, the contaminated soil inlet 16, the heating burners 14 and 15 for heating the contaminated soil located adjacent to the inlet, separating the heat treated soil and other wastes. The method of claim 1 comprising a rotary sorter drum 10 equipped with a screen 11 and an outlet 18 for discharging waste and a blower discharge hood 19 for separating by wind the vinyl component in the waste. Provides a sorting device for contaminated soil to carry out.

Hereinafter, the present invention will be described in more detail.

The present invention is to purify and recover the contaminated soil in the landfill, the process is as follows.

First, the contaminated soils of landfills are excavated, uncoated coarse particles and polymer wastes are separately incinerated, and contaminated soils separated from the screen are removed by various methods of thermal desorption or biotreatment.

Subsequently, organic contaminants such as pesticides, volatile organic compounds (VOCs, SVOCs), and polychlorinated biphenyls contained in the contaminated soil after the pretreatment are decomposed by thermal desorption or microbial reaction processes.

In the thermal desorption process, the contaminated soil is heated to a temperature at which contaminants can be volatilized in the contaminated soil, for example, 150 to 350 ° C., to desorb and remove various contaminants in the contaminated soil by vaporization or thermal oxidative decomposition.

In the microbial reaction process, conditions for microbial growth of the pretreated contaminated soil, for example, pH is adjusted to 7 to 8 (controlled by acid or alkali), humidity to 40 to 50%, and temperature to 30 to 50 ° C, Microorganisms capable of decomposing organic substances, oxygen and various nutrients necessary for respiration growth of these microorganisms are supplied and reacted with contaminated soil to biologically decompose and remove contaminated organic substances in contaminated soil. In this process, contaminated organics in contaminated soil are fed and the oxygen supplied is rapidly decomposed and consumed by the respiratory activity of aerobic and anaerobic microorganisms to produce CO _2, H ₂ O, lower hydrocarbons and heat. A microorganism that can be used in the present invention include Bacillus subtilis (Bacillus subtilis), Bacillus poly miksa (Bacillius polymyxa), also Pseudomonas (Rhodopseudomonas), auto tropic bakteo (Autotrophic bactor), Pseudomonas (Pseudomonas), nitro bakteo (Nitro bacter ), Trichoderma viride , Cellulomonas Ep, Actinomyces , Filamentous fungi , and may be used in combination of two or more thereof. Bacillius sp. Strain KHR-10-MX, cellulomonas sp. KHR-15-MX and the combination strain KHR-5-MX, which are the strains described in the inventors' patent No. 134204, alone or in combination It is preferable to mix and use.

In this way, the contaminated soil in landfills can be purified and recycled into useful land (flower complexes, barns, parks, sports facilities, etc.).

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example 1 Purification of Contaminated Soil by Thermal Desorption Process

Soil was taken from the landfill site of Nanjido, Seoul, and the coarse solid contaminants were screened and incinerated, and the contaminants were separated through the screen. Subsequently, the thermal desorption process was performed using the rotary sorting apparatus shown in FIG. First, the pretreated contaminated soil was introduced into the inlet 16 of the rotary sorter drum 10 having a horizontal cylindrical shape using a conveyor 17. The heating burner 1 (14) and the heating burner 2 (15) are heated to maintain 150 to 350 ° C, and the reduction gear 13 and the cylindrical rotary gear 12 attached to the rotary sorter drum 10 interlock with each other for the drum 10 The heat was transferred directly or indirectly to the drum 10 while rotating the thermally decomposed contaminants.

The sorter was discharged by particle size through the front and rear end screens 11 of the rotary sorter 10, and the residual vinyls were discharged by being separated by wind pressure through the blower discharge hood 19 while being discharged along the guide plate 18.

The removal rate of the contaminated organic material according to the rotational speed and temperature of the contaminated soil was measured by the soil contamination test method and is shown in Table 1 below.

Example 2 Purification of Contaminated Soil by Biological Process

Contaminated soil in Nanjido, Seoul (used as a landfill for 15 years), Sangseo-dong land in Daedeok-gu, Daejeon (used as a landfill for 1 year and 5 months), Singi-dong landfill in Gongju-si (used as a landfill for 7 years) and Gugyo-ri landfill site in Buyeo-eup, Buyeo-eup (used as landfill for 17 years) Each was taken as an excavator, the coarse solid contaminant was selected and incinerated in the same manner as in Example 1, and the screen and wind treatment were used to remove the vinyl component.

Subsequently, the pretreated contaminated soil 112 is introduced into the bioreactor 100 illustrated in FIG. 3, and the temperature of the bioreactor is maintained at 30 to 50 ° C. with the ceramic heater 103 of the temperature controller 101. Bacillus strain KHR-10-MX (Korean Patent No. 134204) was introduced into the strain injection port 105 by adjusting the pH to 7-8 and the humidity to 45%. The fresh air by the blower 107 is passed through the filter 109 while controlling the air flow rate to the flow meter 108 to be supplied through the acid substrate 104, and the bioreactor 100 is operated using the rotation controller 102. The biological reaction proceeded while rotating at 5 to 17 rpm. The generated gas was discharged through the exhaust gas line 106 to be exhausted through the exhaust gas cleaner 110 and the adsorption tower 111.

The dominant species microorganisms and degradation mechanisms in the bioreactor 100 are as follows:

The removal rate of contaminants in the contaminated soil over time in each test group was measured by the soil contamination test method and is shown in Table 2 below.

According to the method of the present invention, the contaminated soil in the landfill can be efficiently purified to prevent environmental pollution, and the purified soil can be reused as useful land to maximize the use of land and save national finances. .

Claims (1)

(1) digging the contaminated soil in the landfill to selectively remove coarse particles and polymer-based waste; (2) screening the contaminated soil particle by screen and separating and removing the vinyl component by wind; And (3) Bacillus sp. KHR-10-MX, Cellulomonas genus after adjusting the pH of the pretreated soil to 7 to 8, the temperature to 30 to 50 ° C. and the humidity to 40 to 50%. Cellulomonas sp.) KHR-15-MX and complex strain KHR-5-MX A method for purifying contaminated soil comprising the step of decomposing organic matter in the soil by introducing at least one microorganism selected from the group.