KR19990050178A - Nitrogen Compound Removal from Coke Wastewater by Ammonia Degassing - Google Patents

Nitrogen Compound Removal from Coke Wastewater by Ammonia Degassing Download PDF

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KR19990050178A
KR19990050178A KR1019970069241A KR19970069241A KR19990050178A KR 19990050178 A KR19990050178 A KR 19990050178A KR 1019970069241 A KR1019970069241 A KR 1019970069241A KR 19970069241 A KR19970069241 A KR 19970069241A KR 19990050178 A KR19990050178 A KR 19990050178A
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ammonia
wastewater
coke wastewater
nitrogen
high concentration
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KR1019970069241A
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KR100345728B1 (en
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최준기
오재완
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이구택
포항종합제철 주식회사
신현준
재단법인 포항산업과학연구원
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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
    • C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
    • C02F1/586—Treatment of water, waste water, or sewage by removing specified dissolved compounds by removing ammoniacal nitrogen
    • 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
    • C02F1/20—Treatment of water, waste water, or sewage by degassing, i.e. liberation of dissolved gases
    • 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
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • 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
    • C02F2103/16—Nature of the water, waste water, sewage or sludge to be treated from metallurgical processes, i.e. from the production, refining or treatment of metals, e.g. galvanic wastes

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  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Physical Water Treatments (AREA)

Abstract

본 발명은 암모니아 탈기법을 이용한 코크스 폐수중 질소 화합물 제거 방법에 관한 것으로,The present invention relates to a method for removing nitrogen compounds in coke wastewater using ammonia degassing,

고농도의 질소 화합물을 함유한 코크스 폐수를 활성 슬러지 공정으로 처리하는데 있어서, 그 전처리 단계로써In the treatment of coke wastewater containing a high concentration of nitrogen compounds by activated sludge process, as a pretreatment step

NaOH pH 조정조에서 상기 코크스 폐수를 교반시켜 암모니아성 질소를 암모니아 가스로 전환시키는 단계;Stirring the coke wastewater in a NaOH pH adjustment bath to convert ammonia nitrogen to ammonia gas;

상기 조정조에서 생성된 암모니아 가스를 암모니아 탈기조에서 제거하는 단계;Removing the ammonia gas generated in the adjusting tank in an ammonia degassing tank;

상기 탈기처리된 폐수는 H2SO4pH 조정조에서 교반시켜 pH 7-8로 낮추어 배출하는 단계;를 거치는 고농도 질소 화합물 제거 방법이 제공된다.The degassed wastewater is discharged by stirring in a H 2 SO 4 pH adjustment tank to lower the pH to 7-8.

본 발명에 의하면, 고농도 질소 화합물 함유 코크스 폐수를 처리하는 생물학적 활성 슬러지 처리 공정에 유입하기 전에 전처리 공정으로써 암모니아 탈기장치를 도입하여 고농도 질소 화합물을 효율적으로 제거할 수 있다.According to the present invention, ammonia degassing apparatus can be introduced as a pretreatment step to efficiently remove high concentration nitrogen compounds before entering the biologically activated sludge treatment process for treating high concentration nitrogen compound-containing coke wastewater.

Description

암모니아 탈기법을 이용한 코크스 폐수중 질소 화합물 제거 방법Nitrogen Compound Removal from Coke Wastewater Using Ammonia Degassing

본 발명은 암모니아 탈기법을 이용한 코크스 폐수중 질소 화합물 제거 방법에 관한 것으로, 보다 상세하게는 제철소 코크스 공장에서 발생되는 고농도 질소 화합물을 함유한 안수중 암모니아 탈기 장치를 이용하여 질소 화합물을 제거하는 방법에 관한 것이다.The present invention relates to a method for removing nitrogen compounds in coke wastewater using ammonia degassing, and more particularly, to a method for removing nitrogen compounds using ammonia degassing apparatus in ordination containing high concentration nitrogen compounds generated in a coke plant in a steel mill. will be.

현재까지는 국내에서 질소 화합물을 제거하는데 적용되는 범용 수처리 기술은 생물학적 처리인 질산화-탈질 공법이 대부분이다. 이 공법은 주로 하수에 적용되고 있으며, 특정 폐수에 대해서는 폐수에 함유되어 있는 질소 화합물의 종류 및 기타 오염물의 함유도에 따라 일률적인 적용이 불가능한 실정이다.Until now, most of the general-purpose water treatment technologies applied to remove nitrogen compounds in Korea are biological nitrification-denitrification methods. This method is mainly applied to sewage, and it is impossible to apply uniformly to certain wastewater depending on the type of nitrogen compound and other contaminants contained in the wastewater.

또한 제철소에서 배출되는 고농도 질소 화합물이 함유된 코크스 폐수의 경우에도 도 1에서와 마찬가지로 일반적인 생물학적 처리 공법을 적용하고 있어 폐수에 함유된 고농도 질소화합물을 효과적으로 제거하기가 곤란하다.In addition, in the case of coke wastewater containing a high concentration of nitrogen compounds discharged from the steel mill, it is difficult to effectively remove the high concentration of nitrogen compounds contained in the waste water, as in the general biological treatment method is applied as in FIG.

즉, 도 1을 참조하여 살펴보면, 코크스 페수에서 발생하는 폐수는 1차적으로 조정조로 유입되는데 이는 수량과 수질을 균등화하려는 목적을 갖는다.That is, referring to Figure 1, the wastewater generated from the coke wastewater is introduced into the adjustment tank primarily, which has the purpose of equalizing the quantity and water quality.

상기 조정조에서 주어진 체류시간만큼 잔류한 고농도 질소 화합물 함유 폐수는 그 다음 단계로 폭기조로 유입되는데 여기서는 활성 미생물을 이용하여 폐수내에 함유된 미생물에 의해 분해가능한 유기물을 제거한다.Wastewater containing high concentrations of nitrogen compounds remaining for a given residence time in the adjusting tank is introduced into the aeration tank as a next step, where the active microorganisms are used to remove organic matter decomposable by the microorganisms contained in the wastewater.

상기 폭기조에서 미생물에 의해 유기물이 제거된 폐수는 다음 단계로 침전지로 유입하여 처리수 방류 목적으로 슬러지와 물 성분의 고액 분리가 일어나게 되며, 침전지에서 분리된 슬러지의 일부는 폐슬러지로서 슬러지 처리 시설로 이송되며, 일부는 폭기조 미생물을 보충하기 위하여 폭기조로 반송되는 공정으로 이루어져 있다.Wastewater from which the organic matter is removed by the microorganisms in the aeration tank flows into the sedimentation basin in the next step, and solid-liquid separation of sludge and water components occurs for the purpose of discharge of the treated water. It is transported, and part consists of the process returned to the aeration tank to replenish the aeration tank microorganisms.

이와 같이 이루어진 공정에서는 폭기조의 미생물에 의해 제거되는 오염물이 미생물에 의해 분해가능한 유기물 성분이며, 질소 화합물도 공정 변경에 따라 질산화-탈질 반응을 이용하여 제거할 수 있으나, 코크스 폐수와 같이 고농도 질소 화합물이 함유되어 있는 경우에는 그 적용이 매우 불안정하다.In this process, the contaminants removed by the microorganisms in the aeration tank are organic components that can be decomposed by the microorganisms. Nitrogen compounds can also be removed by nitrification-denitrification according to the process change, but high concentration nitrogen compounds such as coke wastewater If present, its application is very unstable.

이에 본 발명의 목적은 생물학적 처리 공정인 활성 슬러지 공정에 코크스 폐수를 유입하기 전에 암모니아 탈기 장치를 도입하여 코크스 폐수내의 질소 화합물을 1차적으로 제거하는 고농도 질소화합물 제거 방법을 제공하려는데 있다.Accordingly, an object of the present invention is to provide a high concentration nitrogen compound removal method for removing nitrogen compounds in the coke wastewater by introducing an ammonia degassing device prior to introducing the coke waste water into the activated sludge process, which is a biological treatment process.

도 1은 종래의 폐수 처리 공법의 개략도, 및1 is a schematic view of a conventional wastewater treatment method, and

도 2는 본 발명에 의한 폐수 처리 공정의 개략도이다.2 is a schematic diagram of a wastewater treatment process according to the present invention.

본 발명에 의하면,According to the invention,

고농도의 질소 화합물을 함유한 코크스 폐수를 활성 슬러지 공정으로 처리하는데 있어서, 그 전처리 단계로써In the treatment of coke wastewater containing a high concentration of nitrogen compounds by activated sludge process, as a pretreatment step

NaOH pH 조정조에서 상기 코크스 폐수를 교반시켜 암모니아성 질소를 암모니아 가스로 전환시키는 단계;Stirring the coke wastewater in a NaOH pH adjustment bath to convert ammonia nitrogen to ammonia gas;

상기 조정조에서 생성된 암모니아 가스를 암모니아 탈기조에서 제거하는 단계;Removing the ammonia gas generated in the adjusting tank in an ammonia degassing tank;

상기 탈기처리된 폐수는 H2SO4pH 조정조에서 교반시켜 pH 7-8로 낮추어 배출하는 단계;를 거치는 고농도 질소 화합물 제거 방법이 제공된다.The degassed wastewater is discharged by stirring in a H 2 SO 4 pH adjustment tank to lower the pH to 7-8.

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

본 발명은 코크스 폐수를 암모니아 탈기 장치를 도입하여 질소 화합물을 1차 제거한 다음 생물학적 처리 공정인 활성 슬러지 공정에 유입함으로써 고농도 질소 화합물을 효율적으로 제거한다.The present invention efficiently removes high concentrations of nitrogen compounds by introducing the ammonia degassing apparatus to the coke wastewater to remove the nitrogen compounds first and then to the activated sludge process, which is a biological treatment process.

본 발명에서 처리하고자 하는 고농도 질소 화합물을 함유한 코크스 폐수는 pH가 7전후로, 이중 질소 농도는 공정 구성 및 운전 상황에 따라 상이하나 일반적으로 400-1000mg/l로 매우 높으며 대부분 NH4 +이온형으로 이루어져 있다.The coke wastewater containing high nitrogen compounds to be treated in the present invention has a pH of about 7, and the double nitrogen concentration is different depending on the process configuration and operation, but is generally high at 400-1000 mg / l, and mostly NH 4 + ion type. consist of.

상기 폐수내의 NH4 +성 질소는 수중에서 NH4 +→ NH3+ H+와 같이 반응하여 평형을 유지하는데, pH가 높아지면 오른쪽으로 반응이 진행하고, 수온 상승에 의해서도 NH3생성비가 증가한다.NH 4 + nitrogen in the waste water reacts with NH 4 + → NH 3 + H + in water to maintain equilibrium, but when the pH is increased, the reaction proceeds to the right, and the NH 3 production ratio is increased by increasing the water temperature. .

따라서 본 발명에서는 고농도 질소 화합물을 함유한 코크스 폐수를 먼저 NaOH pH 조정조에서 pH를 10.5-11까지 상승시키면서 교반시켜 암모니아성 질소를 암모니아로 전환시킨다.Therefore, in the present invention, coke wastewater containing a high concentration of nitrogen compound is first stirred while raising the pH to 10.5-11 in a NaOH pH adjusting tank to convert ammonia nitrogen to ammonia.

질소 화합물이 NH3가스 상태로 함유되어 있는 코크스 폐수를 암모니아 탈기조에서 송풍기(blower)로 공기 폭기하여 폐수내의 질소 화합물을 저감시킨다.The coke wastewater containing the nitrogen compound in the NH 3 gas state is aerated by a blower in an ammonia degassing tank to reduce the nitrogen compound in the wastewater.

상기 암모니아 탈기조에서 제거된 암모니아는 기존의 설비 라인에 적용하기 위하여 일단 제습 장치(Demister)를 거친 다음 암모니아 분해로에서 소각 처리한다.The ammonia removed in the ammonia degassing tank is first incinerated in an ammonia cracking furnace after passing through a dehumidifier (Demister) for application to an existing installation line.

이와 같이 탈기처리된 폐수를 그대로 후속 공정인 생물학적 활성 슬러지 공정으로 유입하는 경우에는 강알칼리성 폐수가 미생물에 악영향을 미치므로 이를 방지하기 위하여 H2SO4pH 조정조에서 미생물에 영향이 없는 pH로 낮춘다.In this manner, when entering the degassing of the treated waste water as subsequent processing biological activated sludge process, because the highly alkaline effluent adversely affect microorganism lower in H 2 SO 4 pH-adjusting tank to not affect the microorganisms pH In order to prevent this.

이하, 본 발명의 실시예를 설명한다.Hereinafter, embodiments of the present invention will be described.

실시예Example

코크스 폐수중의 암모니아성 질소 농도가 약 500mg/l인 유입수를 NaOH가 충분히 첨가된 NaOH 조정조에 투입하고 교반한 다음 암모니아 탈기를 거쳐 H2SO4조정조에서 교반시키면서 중화시켜 암모니아성 질소를 제거하였다.The influent water having ammonia nitrogen concentration of about 500 mg / l in the coke wastewater was introduced into a NaOH control tank with sufficient NaOH, stirred, and neutralized while stirring in a H 2 SO 4 control tank through ammonia degassing to remove ammonia nitrogen.

상기 총 체류 시간에 따른 처리수의 암모니아성 질소 농도를 측정하고 이를 하기표 1에 나타내었다.The ammonia nitrogen concentration of the treated water according to the total residence time was measured and shown in Table 1 below.

체류 시간에 따른 코크스 폐수중 암모니아성 질소의 제거 효율Removal Efficiency of Ammonia Nitrogen in Coke Wastewater with Retention Time 체류 시간(hr)Retention time (hr) 처리수 암모니아성 질소 농도(mg/l)Treated Water Ammonia Nitrogen Concentration (mg / l) 제거율(%)% Removal 1One 430430 1414 33 360360 2828 6.56.5 290290 4242

또한 상기 공정중 암모니아 탈기조에서 폭기하기 위해 첨가하는 공기량에 따른 코크스 폐수중의 암모니아성 질소의 제거 효율을 측정하고 그 결과를 하기표 2에 나타내었다.In addition, the removal efficiency of the ammonia nitrogen in the coke wastewater according to the amount of air added to aeration in the ammonia degassing tank during the process was measured and the results are shown in Table 2 below.

공기량에 따른 코크스 폐수중의 암모니아성 질소의 제거 효율Removal Efficiency of Ammonia Nitrogen in Coke Wastewater According to Air Volume 공기량(m3Air/min)Air volume (m 3 Air / min) 처리수 암모니아성 질소 농도(mg/l)Treated Water Ammonia Nitrogen Concentration (mg / l) 제거율(%)% Removal 1,0001,000 460460 7.77.7 2,0002,000 411411 17.817.8 3,0003,000 285285 43.043.0

상기표 1과 2에 의하면, 생물학적 처리 공정인 활성 슬러지 공정에서 고농도 질소 화합물 함유 코크스 폐수를 처리하기 전에 전처리 단계로 암모니아 탈기를 거침으로써 효과적으로 고농도 질소 화합물을 제거함을 알 수 있다.According to Tables 1 and 2 above, it can be seen that the high concentration nitrogen compound is effectively removed by subjecting ammonia degassing to the pretreatment step before treating the high concentration nitrogen compound-containing coke wastewater in the activated sludge process, which is a biological treatment process.

본 발명에 의하면, 고농도 질소 화합물 함유 코크스 폐수를 처리하는 생물학적 활성 슬러지 처리 공정에 유입하기 전에 전처리 공정으로써 암모니아 탈기장치를 도입하여 고농도 질소 화합물을 효율적으로 제거할 수 있다.According to the present invention, ammonia degassing apparatus can be introduced as a pretreatment step to efficiently remove high concentration nitrogen compounds before entering the biologically activated sludge treatment process for treating high concentration nitrogen compound-containing coke wastewater.

Claims (1)

고농도의 질소 화합물을 함유한 코크스 폐수를 활성 슬러지 공정으로 처리하는데 있어서, 그 전처리 단계로써In the treatment of coke wastewater containing a high concentration of nitrogen compounds by activated sludge process, as a pretreatment step NaOH pH 조정조에서 상기 코크스 폐수를 교반시켜 암모니아성 질소를 암모니아 가스로 전환시키는 단계;Stirring the coke wastewater in a NaOH pH adjustment bath to convert ammonia nitrogen to ammonia gas; 상기 조정조에서 생성된 암모니아 가스를 암모니아 탈기조에서 제거하는 단계;Removing the ammonia gas generated in the adjusting tank in an ammonia degassing tank; 상기 탈기처리된 폐수는 H2SO4pH 조정조에서 교반시켜 pH 7-8로 낮추어 배출하는 단계;를 거치는 암모니아 탈기법을 이용한 코크스 폐수중 고농도 질소 화합물 제거 방법The degassed wastewater is agitated in a H 2 SO 4 pH adjustment tank to lower the pH to 7-8 and discharged. The method for removing high concentration nitrogen compounds in the coke wastewater using the ammonia degassing method.
KR1019970069241A 1997-12-16 1997-12-16 Method for eliminating nitrogen compounds from coke wastewater using ammonia stripping KR100345728B1 (en)

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CN104162449A (en) * 2014-08-22 2014-11-26 陕西驭腾实业有限公司 Pyrolysis catalyst for coking wastewater and preparation method of pyrolysis catalyst
CN104891702A (en) * 2014-03-06 2015-09-09 彭传义 Three-phase azeotropy ammonia removing reactor

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CN109626694B (en) * 2019-01-23 2022-06-17 杭州卧特松环保科技有限公司 Process for purifying high-salt high-ammonia nitrogen wastewater

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KR100195579B1 (en) * 1997-02-27 1999-06-15 이광열 Method for treating waste water containing ammonia nitrogen

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104891702A (en) * 2014-03-06 2015-09-09 彭传义 Three-phase azeotropy ammonia removing reactor
CN104162449A (en) * 2014-08-22 2014-11-26 陕西驭腾实业有限公司 Pyrolysis catalyst for coking wastewater and preparation method of pyrolysis catalyst

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