KR20000040926A - Treating method of wastewater using slag - Google Patents

Treating method of wastewater using slag Download PDF

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Publication number
KR20000040926A
KR20000040926A KR1019980056680A KR19980056680A KR20000040926A KR 20000040926 A KR20000040926 A KR 20000040926A KR 1019980056680 A KR1019980056680 A KR 1019980056680A KR 19980056680 A KR19980056680 A KR 19980056680A KR 20000040926 A KR20000040926 A KR 20000040926A
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South Korea
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slag
mine
wastewater
groundwater
acidic
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KR1019980056680A
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Korean (ko)
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김창균
전희동
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신현준
재단법인 포항산업과학연구원
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Priority to KR1019980056680A priority Critical patent/KR20000040926A/en
Publication of KR20000040926A publication Critical patent/KR20000040926A/en

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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/10—Nature of the water, waste water, sewage or sludge to be treated from quarries or from mining activities

Abstract

PURPOSE: A treating method of acidic wastewater in mine using slag is provided, which is characterized in that wastewater in mine is neutralized and, manganese or aluminium ions are adsorbed by the slag. CONSTITUTION: A method is composed of a slag layer(3) which acidic underground water(1) in mine(7) is passed, a strainer(4) for preventing from discharging slag, and a discharging pipe(8) for discharging treated underground water. In the case of general extraction experiment of slag, the amount of calcium is 200 mg/, but in the case of TCLP(Toxicity Characteristic Leaching Procedure), the amount of slag is 8 times more. Wastewater in mine is neutralized using slag controlling pH 8, and manganese ion and aluminium ion are adsorbed by slag or removed as metal hydrate.

Description

슬래그를 이용한 광산폐수 처리방법Mine Wastewater Treatment Using Slag

본 발명은 폐석탄 광산의 폐 갱내에서 발생하는 산성의 폐 지하수를 제철소 발생 부산물인 슬래그를 이용하여 효과적으로 중화 처리하는 방법에 관한 것이다.The present invention relates to a method for effectively neutralizing acidic groundwater generated in a waste pit of a waste coal mine using slag as a by-product of steel mill generation.

석탄 광산 개발과정과 개발 후 갱내를 적절한 채움재를 이용하여 갱을 폐쇄하지 않을 경우 갱내는 공기와 직접 접촉 혹은 공기가 용존된 지하수와 접촉하여 석탄 지역에 포함되어 있는 FeS와 접촉하게 되어 아래와 같은 산성의 폐 지하수를 발생시킨다.If the pit is not closed using the appropriate filling material in the coal mine development process and after the development, the pit will come into contact with FeS contained in the coal area by direct contact with air or with groundwater where air is dissolved. Generate waste groundwater.

FeS2+ 2H2O + 3O2→Fe2++ 2H2SO4 FeS 2 + 2H 2 O + 3O 2 → Fe 2+ + 2H 2 SO 4

이 폐 지하수는 pH가 3~6 정도로 낮아 주변 광석에 함유되어 있는 Al 및 Mn 등의 성분을 용출시켜 인접 수계로 유출시키게 된다.The waste groundwater has a low pH of 3 to 6, and elutes components such as Al and Mn contained in the surrounding ore and flows into the adjacent water system.

현재까지 가장 잘 알려진 방법은 석회석을 이용하여 중화 처리하거나 황 환원 박테리아를 이용하여 환원시켜 제거하는 방법이 이용되고 있다.To date, the most well known methods are neutralization using limestone or reduction by removal using sulfur reducing bacteria.

상기 석회석은 가격이 톤당 약 10000원 정도 하고 있으며 광산의 규모에 따라 수천톤씩 중화처리용으로 폐광산에 적용되고 있다.The limestone is priced at about 10,000 won per ton, and is applied to waste mines for neutralization by thousands of tons depending on the size of the mine.

이는 폐 광산 발생 지하수 처리를 주관하는 사업주에 매우 큰 경제적인 부담이 될 수 있다.This can be a very economic burden for employers who manage waste mine generation groundwater treatment.

한편, 박테리아 이용방법도 적용되고 있으나, 이는 계절에 따른 온도 변화나 폐광산 지하수를 저류하여 처리할 수 있는 넓은 지역이 필요하다.On the other hand, the use of bacteria has also been applied, but this requires a large area that can be treated by seasonal temperature changes or stored underground mine groundwater.

또한, 황을 환원 제거할 수 있는 박테리아는 혐기성 미생물로 공기가 없는 상태에서만 생장할 수가 있어 만약 이 들이 공기에 노출될 경우 폐광산 발생 지하수 처리에 큰 문제가 발생하게 된다.In addition, bacteria capable of reducing and removing sulfur can be grown only in the absence of air as anaerobic microorganisms, and if they are exposed to air, a great problem arises in treating waste mine-generated groundwater.

또한, 겨울에는 온도가 낮아져 이들 미생물의 생장이 둔화되어 처리효율이 급격히 저하된다.In addition, in winter, the temperature is lowered, the growth of these microorganisms is slowed down, and the treatment efficiency is drastically lowered.

상기와 같이, 종래 방법들은 경제성이나 기술적인 측면에서 많은 문제점을 내포하고 있어 그 적용에 한계성을 갖고 있다.As described above, the conventional methods have many problems in economical or technical aspects and have limitations in their application.

본 발명자들은 상기한 종래방법의 제반 문제점을 해결하기 위하여 연구를 행하고, 그 결과에 근거하여 본 발명을 행하게 된 것으로서, 본 발명은 광산폐수를 중화 처리하는 방법에 있어 고로슬래그를 폐갱내 채움재로 이용하여 광산 발생 산성 지하수를 수계 유출 전 슬래그층을 통과시켜 중화시킬 뿐만 아니라 지하수중에 포함되어 있는 Mn과 Al이온등을 슬래그에 흡착 제거시킬 수 있는 슬래그를 이용한 광산폐수 처리 방법을 제공하고자 하는데, 그 목적이 있다.The present inventors have conducted research to solve the above problems of the conventional method, and based on the results, the present invention uses the blast furnace slag as a filling material in the mine shaft in the method of neutralizing the mine wastewater. It is intended to provide a method for treating mine wastewater using slag that can neutralize acid generated underground water through the slag layer prior to the outflow of water, and also adsorb and remove Mn and Al ions contained in the groundwater to the slag. There is this.

도 1은 본 발명을 구현할 수 있는 광산폐수 중화처리장의 일례를 나타내는 개략도1 is a schematic diagram showing an example of a mine wastewater neutralization treatment plant that can implement the present invention

도 2는 광산 발생 산성 지하수의 유량변화에 따른 pH의 변화를 나타내는 그래프Figure 2 is a graph showing the change in pH according to the flow rate of acid generated underground ground water

* 도면의 주요부분에 대한 부호의 설명 *Explanation of symbols on the main parts of the drawings

1... 광산 발생 산성 지하수 2... 슬래그 채움 층 6... 처리수1. mine-generated acidic groundwater 2 ... slag-filled layer 6 ... treated water

이하, 본 발명에 대하여 설명한다.EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated.

본 발명은 광산폐수를 처리하는 방법에 있어서, 고로 슬래그를 폐갱내 채움재로 이용하여 슬래그 채움층을 형성하여 광산 발생 산성 지하수를 수계 유출 전에 상기 고로 슬래그층을 통과시켜 pH를 8이상으로 한 다음, pH가 6이하인 광산 발생 산성 지하수에 혼합하여 중화시켜 광산 발생 산성 지하수를 처리하는 슬래그를 이용한 광산폐수 처리 방법에 관한 것이다.The present invention is a method for treating mine wastewater, using a blast furnace slag as a filling material in the mine shaft to form a slag filling layer to pass the blast furnace slag layer before the outflow of the acid generated acidic groundwater to the pH to 8 or more, The present invention relates to a method for treating mine wastewater using slag which is neutralized by mixing with neutralized acidic groundwater having a pH of 6 or less.

이하, 본 발명에 대하여 상세히 설명한다.EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

본 발명에서 중화처리될 수 있는 광산폐수는 석탄 광산의 폐 갱도에서 발생하는 pH 3~6의 산성의 지하수등을 들 수 있으며, 이러한 산성의 지하수에는 통상 28~34mg/L 정도의 망간 이온 및 2~3 mg/L 정도의 알루미늄 이온등이 포함되어 있다.Acid wastewater that can be neutralized in the present invention may include acidic groundwater having a pH of 3 to 6 generated in the coal mine of coal mines, and such acidic groundwater usually contains about 28 to 34 mg / L of manganese ions and 2 Aluminum ions of about 3 mg / L are included.

본 발명에서 폐갱내 채움재로 이용되는 고로 슬래그로는 통상 미국 EPA에서 제정한 산성 조건의 용출실험 방법인 TCLP(Toxicity Characteristic Leaching Procedure)법 시험을 통과한 슬래그등을 들 수 있으며, 그 대표적인 고로 슬래그 조성은 하기 표 1과 같다.Blast furnace slag used in the present invention as a filling material in the pulmonary cavity includes slag that has passed the TCLP (Toxicity Characteristic Leaching Procedure) test, which is a dissolution test method under acidic conditions usually established by the US EPA, and the representative blast furnace slag composition Is shown in Table 1 below.

[고로 슬래그의 용출실험 결과(농도 : mg/L)][Effusion Experiment Results of Blast Furnace Slag (Concentration: mg / L)] CaCa AsAs CdCD PbPb AgAg SeSe BaBa Cr6+ Cr 6+ 용출시험결과Dissolution test result 16401640 TrTr TrTr TrTr TrTr TrTr TrTr TrTr 기준standard 55 1One 55 55 1One 100100 55

상기 표 1에 나타난 바와 같이, 통상 공해공정법의 슬래그 용출실험은 pH 중성 조건하에서 실시되며 이 경우 고로 슬래그의 Ca 용출량은 200mg/L를 나타내지만 TCLP 법에 의해 산성 조건하에서 용출된 슬래그는 이 보다 8배나 높은 농도를 나타냄을 알 수 있는데, 이는 TCLP 법에 의하여 보다 정확히 고로 슬래그의 알칼리성을 이용한 중화제 역할을 결정할수 있다.As shown in Table 1, the slag dissolution test of the conventional pollution process method is carried out under pH neutral conditions, in which case the amount of Ca elution of blast furnace slag is 200mg / L, but the slag eluted under acidic conditions by TCLP method It can be seen that the concentration is 8 times higher, which can be more accurately determined by the TCLP method using the alkalinity of the blast furnace slag.

또한, 용출 실험 결과 산성 조건하에서도 모든 유해성분이 미량함유(Trace)수준으로 나타나 폐광산지역의 중화제로 이용되더라도 유해성 문제가 야기되지 않음을 알수 있다.In addition, the dissolution test results show that all harmful components are trace level even under acidic conditions, so that even if used as a neutralizer in the abandoned mine area, no harmful problem is caused.

본 발명에서는 광산 발생 산성의 지하수를 고로 슬래그가 채워진 슬래그채움층을 통과시켜 지하수의 pH가 8이상이 되도록 상승시킨 다음, pH가 6이하인 광산 발생 산성 지하수에 혼합하여 pH가 7정도가 되도록 하여 최종적으로 수계로 유출시킨다.In the present invention, the acidic ground water of the mine generated acid is passed through the slag-filled slag-filled layer to raise the pH of the groundwater to 8 or more, and then mixed with the acid generated acidic ground water having a pH of 6 or less so that the pH is about 7 To the water system.

상기와 같이 본 발명에 따라 고로 슬래그를 이용하여 광산 발생 산성 지하수를 처리하므로써, 부가적으로 상기 산성 지하수중에 포함되어 있는 Mn과 Al 이온등이 동시에 슬래그에 흡착 제거된다.By treating the mine-generated acidic groundwater using the blast furnace slag according to the present invention as described above, Mn and Al ions and the like contained in the acidic groundwater are additionally adsorbed and removed at the same time.

본 발명에 있어서, 광산 발생 산성 지하수에 대한 고로 슬래그의 사용량은 광산 발생 산성 지하수의 pH값에 근거하여 결정하는 것이 바람직하며, 보다 바람직하게는 광산 발생 산성 지하수의 pH값 및 함유되어 있는 Mn 및 Al 이온등의 함량등에 기초하여 결정하는 것이 바람직하다.In the present invention, the amount of blast furnace slag used for the acid generated acidic groundwater is preferably determined based on the pH value of the acid generated acidic groundwater, and more preferably the pH value of the acid generated acidic groundwater and the contained Mn and Al. It is preferable to determine based on the content of ions and the like.

본 발명에 있어서는 예를 들면, 약 3000톤의 슬래스를 채움재로 사용하는 경우에는 분당 약 750L의 산성의 지하수를 중화처리할 수 있으며, 이때의 슬래그 알칼리도 생산량은 하루 약 800kg/day가 돤다.In the present invention, for example, when using about 3000 tons of slag as a filler, about 750 liters of acidic groundwater per minute can be neutralized, and the slag alkalinity is about 800 kg / day per day.

이하, 실시예를 통하여 본 발명을 보다 구체적으로 설명한다.Hereinafter, the present invention will be described in more detail with reference to Examples.

실시예Example

도 1에는 본 발명이 적용될 수 있는 광산폐수 중화처리장의 일례가 나타나 있는데, 본 실험에서는 이 광산폐수 중화처리장을 이용하였다.1 shows an example of a mine wastewater neutralization plant to which the present invention can be applied. In this experiment, this mine wastewater neutralization plant was used.

상기 광산폐수 중화처리장은 도 1에 나타난 바와 같이, 갱내(7)의 산성 지하수(1)가 통과되는 고로슬래그가 충진된 슬래그 채움층(3), 슬래그의 유출을 방지하기 위한 스트레이너(4), 스트레이너(4)를 통과한 처리수가 수두차에 의하여 수계로 방출되는 방출관(8)으로 구성되어 있다.The mine wastewater neutralization treatment plant, as shown in Figure 1, the blast furnace slag-filled slag filling layer (3) through which the acidic groundwater (1) in the pit (7) passes, a strainer (4) for preventing the outflow of slag, It consists of the discharge pipe 8 which discharges the process water which passed the strainer 4 to water system by the head difference.

도 1에서 부호 2는 산성 지하수 층을, 부호 5는 웨어를, 그리고 부호 6은 처리수를나타낸다.In FIG. 1, 2 represents an acidic groundwater layer, 5 represents a weir, and 6 represents treated water.

도 1의 슬래그 채움층(3)에는 상기 표 1의 조성을 갖는 고로 슬래그를 채웠다.The slag filling layer 3 of FIG. 1 was filled with blast furnace slag having the composition of Table 1 above.

pH가 6인 광산 발생 산성 지하수를 도 2와 같이 유량을 변화시키면서 상기와 같이 고로 슬래그가 채워진 슬래그 채움층을 통과시켜 통과 유량에 따른 처리수의 pH변화를 조사하고, 그 결과를 도 2에 나타내었다.Passing the blast furnace slag-filled slag-filled layer as described above while changing the flow rate of the acid-produced acidic groundwater having a pH of 6, the pH change of the treated water according to the flow rate was investigated, and the result is shown in FIG. It was.

도 2에 나타난 바와 같이, 광산 발생 산성 지하수의 통과 유량 500mL에서 부터 처리수의 pH는 8이상을 나타내고 있음을 알 수 있는데, 이것은 고로 슬래그가 산성 지하수의 pH를 8정도로 유지하는데 매우 유용하다는 것을 의미하는 것이다.As shown in FIG. 2, it can be seen that the treated water has a pH of 8 or more from a flow rate of 500 mL of photoacidic acidic groundwater, which means that the blast furnace slag is very useful for maintaining the pH of the acidic groundwater at about 8. It is.

상기와 같이 처리된 처리수는 pH가 6인 광산 발생 산성 지하수와 1:1의 부피비로 희석 혼합되어 pH가 7로 조정되어 수계로 최종 방류된다.The treated water treated as described above is diluted and mixed in a volume ratio of 1: 1 with photoacidic acidic groundwater having a pH of 6, and the pH is adjusted to 7 to be finally discharged into the water system.

한편, 채워진 슬래그의 사용주기는 슬래그의 일정 유량 유속이 감소하는 시점을 기준으로 슬래그를 교체한 후 다시 채워줘 사용하면 된다.On the other hand, the use period of the filled slag is to replace the slag on the basis of the point when the fixed flow rate of the slag is reduced and then refill it to use.

상술한 바와 같이, 본 발명은 고로 슬래그를 이용하여 광산폐수를 중화 처리하여 pH를 8정도로 조절함과 동시에 폐수 중에 함유되어 있는 Mn과 Al이온을 슬래그에 흡착 제거하거나 슬래그층을 통과한 후 금속 수화물 침전물로서 제거할수 있어 광산폐수 발생으로 인한 주변 생태계의 파괴를 경제적이고도 기술적으로 용이하게 방지할수 있는 효과가 있는 것이다.As described above, the present invention neutralizes the mine wastewater by using the blast furnace slag to adjust the pH to about 8, while simultaneously adsorbing and removing the Mn and Al ions contained in the wastewater to the slag or passing through the slag layer, the metal hydrate As it can be removed as a sediment, it is economically and technically easy to prevent the destruction of the surrounding ecosystem due to the generation of mine wastewater.

Claims (1)

광산폐수를 처리하는 방법에 있어서, 고로 슬래그를 폐갱내 채움재로 이용하여 슬래그 채움층을 형성하여 광산 발생 산성 지하수를 수계 유출전에 상기 슬래그 채움층을 통과시켜 pH를 8이상으로 한 다음, pH가 6이하인 광산 발생 산성 지하수에 혼합하여 중화시켜 광산 발생 산성 지하수를 처리하는 것을 특징으로 하는 슬래그를 이용한 광산폐수 처리 방법In the method of treating mine wastewater, the slag filling layer is formed by using the blast furnace slag as the filling material in the abandoned mine shaft, and the acid generated underground groundwater is passed through the slag filling layer before the outflow of the water so that the pH is 8 or more, and then the pH is 6 A method for treating mine wastewater using slag, characterized in that it is mixed with neutralized acid-produced acidic groundwater which is less than and neutralized to treat acid-produced acidic ground water.
KR1019980056680A 1998-12-21 1998-12-21 Treating method of wastewater using slag KR20000040926A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20010044785A (en) * 2001-03-24 2001-06-05 김헌출 Remediation of contaminated subsurface using reactive barriers having blast furnace slag or steel-manufacturing slag
KR100342766B1 (en) * 2000-11-16 2002-07-03 권형기 Remediation method of contaminated substances using subsidiary reactive barriers having blast furnace slag or steel manufacturing slag
KR100397236B1 (en) * 2000-11-16 2003-09-19 한라산업개발 주식회사 Remediation method of contaminated subsurface and chlorinated organic compounds of ground water using hrm sludge or e/p dust
RU2622132C1 (en) * 2016-05-17 2017-06-13 федеральное государственное бюджетное образовательное учреждение высшего образования "Пермский национальный исследовательский политехнический университет" Way to neutralise the acidic mine waters
CN109626905A (en) * 2018-12-29 2019-04-16 紫金矿业集团股份有限公司 A method of underground filling is used for based on slag is neutralized

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100342766B1 (en) * 2000-11-16 2002-07-03 권형기 Remediation method of contaminated substances using subsidiary reactive barriers having blast furnace slag or steel manufacturing slag
KR100397236B1 (en) * 2000-11-16 2003-09-19 한라산업개발 주식회사 Remediation method of contaminated subsurface and chlorinated organic compounds of ground water using hrm sludge or e/p dust
KR20010044785A (en) * 2001-03-24 2001-06-05 김헌출 Remediation of contaminated subsurface using reactive barriers having blast furnace slag or steel-manufacturing slag
RU2622132C1 (en) * 2016-05-17 2017-06-13 федеральное государственное бюджетное образовательное учреждение высшего образования "Пермский национальный исследовательский политехнический университет" Way to neutralise the acidic mine waters
CN109626905A (en) * 2018-12-29 2019-04-16 紫金矿业集团股份有限公司 A method of underground filling is used for based on slag is neutralized

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