WO2010008253A2 - 염소계 화합물을 이용한 배가스 내 수은 제거 방법 - Google Patents
염소계 화합물을 이용한 배가스 내 수은 제거 방법 Download PDFInfo
- Publication number
- WO2010008253A2 WO2010008253A2 PCT/KR2009/003984 KR2009003984W WO2010008253A2 WO 2010008253 A2 WO2010008253 A2 WO 2010008253A2 KR 2009003984 W KR2009003984 W KR 2009003984W WO 2010008253 A2 WO2010008253 A2 WO 2010008253A2
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- WIPO (PCT)
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- mercury
- naclo
- exhaust gas
- elemental mercury
- clo
- Prior art date
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/64—Heavy metals or compounds thereof, e.g. mercury
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/54—Nitrogen compounds
- B01D53/56—Nitrogen oxides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/75—Multi-step processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/10—Oxidants
- B01D2251/108—Halogens or halogen compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/30—Alkali metal compounds
- B01D2251/304—Alkali metal compounds of sodium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/60—Inorganic bases or salts
Definitions
- the present invention relates to a method for efficiently removing elemental mercury from flue gas using a chlorine-based compound, and more particularly, OClO, ClO, ClOO, generated by the reaction of NOx contained in the flue gas with NaClO 2 injected from the outside
- the present invention relates to a method for removing elemental mercury, which is difficult to remove by conventional methods, to mercuric oxide, which is a more easily removed form, by using powerful oxidants such as Cl, Cl 2 and transient Cl species.
- mercury exists in the form of an alloy (amalgam) with other metals in nature or HgS reacted with sulfur, which is harmless to the environment and the human body.
- HgS reacted with sulfur
- the situation is different when the element is reduced to elemental mercury and released as exhaust gas by high temperature.
- Mercury reacted with various chemical species in the flue gas is released into the air in toxic forms such as elemental mercury, mercury oxide and particulate mercury.
- the composition ratio of mercury compounds in the flue-gas produced through the combustion process varies depending on the chlorine, sulfur composition, and combustion temperature in the raw materials.
- the proportion of mercury will increase.
- elemental mercury is relatively inactive compared to mercury oxide or particle mercury and is very difficult to remove. Therefore, attempts to oxidize and remove elemental mercury that are difficult to remove with existing air pollution prevention facilities have been studied in the past.
- US 2005/0255022, US 2008/0060520, and Korean Patent Publication No. 2007-0040752 disclose a method of removing elemental mercury using hydrogen peroxide.
- US Patent US 2003/0161771 also introduces a halogen molecule or pyrolysis method to inject a thermolabile molecular halogen precursor into a flue gas and oxidize elemental mercury to Ca (OCl) 2 , MgBr 2 , KI. The same compound as 3 was used.
- US Pat. No. 6,294,139 and Korean Patent No. 0367140 propose a method of oxidizing elemental mercury in a wet scrubber to generate a material capable of oxidizing elemental mercury by reacting NaClO 2 with HCl in a scrubbing solution.
- the present invention is to solve the problems of the above-mentioned prior art and to provide a method for efficiently and easily removing elemental mercury from flue gas, which economically removes trace amounts of mercury contained in flue gas without significant facility investment and operating costs. To provide a method.
- the present invention which calls for, elemental mercury, and NaClO 2 injection step of injecting NaClO 2 in the exhaust gas containing NOx, elemental mercury in the NaClO 2 and said NOx form an oxidant to the above-mentioned objects as mercury oxidation reforming step and It provides a mercury removal method comprising a mercury oxide removal step of removing the mercury oxide from the exhaust gas.
- the NaClO 2 may be injected into the mixture on the powder, aqueous solution or a powder and an aqueous solution, the oxidizing agent is NaClO 2 and a gas phase reaction or gas phase - consisting of OClO, ClO, ClOO and Cl 2 is formed by a solid phase reaction It may be one kind or two or more kinds selected from the group.
- the mercury oxide may be one or two or more selected from the group consisting of HgO, HgOCl and HgCl 2 .
- the mercury oxide removal step may be performed by one or two methods selected from the group consisting of an electrostatic precipitator, a filter precipitator, and a wet scrubber or a wet desulfurization plant.
- a small amount of mercury contained in the exhaust gas can be efficiently removed at low cost by injecting NaClO 2 into the exhaust gas to generate an oxidizing agent capable of effectively oxidizing elemental mercury.
- OClO, ClO, ClOO, Cl, and Cl 2 are formed to react with NO x contained in the flue gas to oxidize elemental mercury.
- it provides a method of removing elemental mercury in the exhaust gas using NaClO 2 comprising a second step of removing the mercury oxide from the exhaust gas.
- the present invention not only effectively removes elemental mercury, which is difficult to remove with existing air pollution prevention equipment, but also injects chemical additives into the exhaust gas in order to solve the problems in view of the prior art.
- the method of oxidizing mercury to mercury oxide is applied.
- the elemental mercury is converted to mercury oxide according to the present invention, its solubility is greatly increased as shown in Table 1 below.
- OClO, ClO, ClOO, Cl, and Cl 2 are gas phases that can effectively oxidize elemental mercury by chemically reacting with NOx present in the flue gas. Since it is sufficiently generated in), it is possible to convert elemental mercury to mercury oxide more effectively than in the prior art, and it is possible to remove mercury oxide even by applying a method using an electrostatic precipitator, a bag filter, and a wet scrubber.
- NaClO 2 powder or an aqueous solution is first injected to produce a strong oxidant capable of oxidizing elemental mercury contained in the flue gas to mercury oxide.
- a strong oxidant capable of oxidizing elemental mercury contained in the flue gas to mercury oxide.
- the NaClO 2 aqueous solution is injected into the flue gas, the moisture contained in the NaClO 2 mist is evaporated due to the hot flue gas, and NaClO 2 having a few micro size is present in the flue gas.
- the injected NaClO 2 particles and NOx generally present in the flue-gas cause a gas-solid phase reaction (see Schemes (1) and (2) below).
- the oxidant thus produced reacts with elemental mercury to produce HgO, HgOCl and HgCl 2 .
- the following reactions are represented by the following reaction formulas (9) to (19).
- the mercury oxide converted into the oxidized form can be easily removed by an electrostatic precipitator, a filter precipitator and a wet scrubber or a wet desulfurization plant.
- a flue gas with a flow rate of 2.6 l / m containing 150 ppm of NO 2 was passed through a fluidized bed of 1.2 g of NaClO 2 at 130 ° C of exhaust gas temperature, and then 1 l / m containing an elemental mercury concentration of 260 ⁇ g / m 3 at a subsequent stage. When reacted by injection, elemental mercury does not react at all.
- NO 2 reacts with NaClO 2 to form OClO.
- OClO alone does not contribute to oxidizing elemental mercury due to its low reactivity with mercury, whereas OClO generated when NO is present together. It can be seen that and reacts rapidly with NO to generate ClO, ClOO, Cl, and Cl 2 , which play an important role in oxidizing elemental mercury through ClO and the reactions mentioned in Table 2 below. In this process, NO is oxidized to NO 2 and elemental mercury is oxidized to HgO, HgOCl, and HgCl 2 .
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Treating Waste Gases (AREA)
Abstract
Description
특성 | Hg | HgO | HgCl2 |
수용해도(㎍/ℓ)@20℃, 1atm | 20 | 69,000,000 | 53,000 @25℃ |
Claims (5)
- 원소 수은 및 NOx를 포함하는 배가스에 NaClO2를 주입하는 NaClO2 주입 단계;상기 NaClO2와 상기 NOx가 산화제를 형성하여 원소 수은을 산화 수은으로 전화하는 전환단계; 및상기 배가스로부터 산화 수은을 제거하는 산화 수은 제거 단계;를 포함하는 것을 특징으로 하는 수은 제거 방법.
- 제1항에 있어서, 상기 NaClO2는 분말, 수용액상 또는 분말 및 수용액상의 혼합상으로 주입하는 것임을 특징으로 하는 수은 제거 방법.
- 제1항에 있어서, 상기 산화제는 NaClO2와 기상 반응 또는 기상-고상 반응을 통해 형성되는 OClO, ClO, ClOO 및 Cl2로 이루어지는 그룹에서 선택된 1종 또는 2종 이상임을 특징으로 하는 수은 제거 방법.
- 제1항에 있어서, 상기 산화 수은은 HgO, HgOCl 및 HgCl2로 구성되는 그룹에서 선택되는 1종 또는 2종 이상인 것을 특징으로 하는 수은 제거 방법.
- 제1항에 있어서, 상기 산화 수은 제거 단계는 전기 집진기, 여과 집진기 및 습식 스크러버 또는 습식 탈황설비로 이루어지는 그룹에서 선택된 1종 또는 2종의 방법에 의해 이루어지는 것임을 특징으로 하는 수은 제거 방법.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN200980104537XA CN101939082A (zh) | 2008-07-17 | 2009-07-17 | 利用了氯系化合物的废气内汞除去方法 |
JP2010535896A JP4733784B2 (ja) | 2008-07-17 | 2009-07-17 | 塩素系化合物を用いた排ガス中の水銀を除去する方法 |
US12/743,604 US8017096B2 (en) | 2008-07-17 | 2009-07-17 | Method of removing mercury from exhaust gas using chlorine compound |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR10-2008-0069595 | 2008-07-17 | ||
KR1020080069595A KR100953535B1 (ko) | 2008-07-17 | 2008-07-17 | 염소계 화합물을 이용한 배가스 내 수은 제거 방법 |
Publications (2)
Publication Number | Publication Date |
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WO2010008253A2 true WO2010008253A2 (ko) | 2010-01-21 |
WO2010008253A3 WO2010008253A3 (ko) | 2010-05-14 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/KR2009/003984 WO2010008253A2 (ko) | 2008-07-17 | 2009-07-17 | 염소계 화합물을 이용한 배가스 내 수은 제거 방법 |
Country Status (5)
Country | Link |
---|---|
US (1) | US8017096B2 (ko) |
JP (1) | JP4733784B2 (ko) |
KR (1) | KR100953535B1 (ko) |
CN (1) | CN101939082A (ko) |
WO (1) | WO2010008253A2 (ko) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20160002952A (ko) * | 2013-04-26 | 2016-01-08 | 사노피 | 5-클로로-티오펜-2-카복실산 [(s)-2-[메틸-3-(2-옥소-피롤리딘-1-일)-벤젠설포닐아미노]-3-(4-메틸 피페라진-1-일)-3-옥소-프로필]아미드의 타르트레이트 염 |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107261811B (zh) * | 2017-07-18 | 2021-02-05 | 叶俊歆 | 一种用于处理含汞工业废气的过滤分离装置 |
KR102404379B1 (ko) * | 2021-11-29 | 2022-05-31 | 대구대학교 산학협력단 | 고체상의 염화암모늄의 열분해를 이용한 원소수은 산화 및 질소산화물 제거 장치 및 이를 이용한 원소수은 산화 및 질소산화물 제거방법 |
Citations (3)
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JP2001162135A (ja) * | 1999-12-10 | 2001-06-19 | Mitsubishi Heavy Ind Ltd | 水銀除去方法 |
KR20020044537A (ko) * | 2000-12-05 | 2002-06-15 | 로버트 제이. 에드워즈 | 원소형 수은 배출의 제어 방법 |
KR100367140B1 (ko) * | 1994-09-21 | 2003-02-19 | 라브 에스. 아. | 기체를습식정화하여기체오염물질을제거하는방법 |
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JPS63315136A (ja) | 1987-04-03 | 1988-12-22 | Zensuke Inoue | 排ガス中の水銀および窒素酸化物の同時除去方法 |
US6117333A (en) * | 1997-04-22 | 2000-09-12 | Union Oil Company Of California | Removal of hydrocarbons, mercury and arsenic from oil-field produced water |
US6284199B1 (en) * | 1999-03-31 | 2001-09-04 | Mcdermott Technology, Inc. | Apparatus for control of mercury |
US6808692B2 (en) | 2002-02-14 | 2004-10-26 | Oehr Klaus H | Enhanced mercury control in coal-fired power plants |
US20040131523A1 (en) | 2002-06-05 | 2004-07-08 | Exxonmobil Research And Engineering Company | Oxidation of NOx's with chlorine dioxide in combination with a thermal NOx removal process |
US7628967B2 (en) | 2002-10-01 | 2009-12-08 | Airborne Industrial Minerals, Inc. | Removal of Hg, NOx, and SOx with using oxidants and staged gas/liquid contact |
JP4098698B2 (ja) | 2003-10-22 | 2008-06-11 | 株式会社日本触媒 | 排ガス処理方法 |
US7264784B2 (en) | 2003-10-22 | 2007-09-04 | Nippon Shokubai Co., Ltd. | Method for treating exhaust gas |
US7514052B2 (en) | 2004-01-06 | 2009-04-07 | General Electric Company | Method for removal of mercury emissions from coal combustion |
KR20070040752A (ko) | 2004-05-11 | 2007-04-17 | 네셔날 에어로노틱스 앤드 스페이스 어드민스트레이션 | SOx, NOx 및 중금속 배출을 감소시키기 위하여과산화수소를 사용하는 방법 및 장치 |
US7582271B2 (en) | 2004-05-11 | 2009-09-01 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Emission control system |
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-
2008
- 2008-07-17 KR KR1020080069595A patent/KR100953535B1/ko active IP Right Grant
-
2009
- 2009-07-17 JP JP2010535896A patent/JP4733784B2/ja not_active Expired - Fee Related
- 2009-07-17 US US12/743,604 patent/US8017096B2/en not_active Expired - Fee Related
- 2009-07-17 CN CN200980104537XA patent/CN101939082A/zh active Pending
- 2009-07-17 WO PCT/KR2009/003984 patent/WO2010008253A2/ko active Application Filing
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JP2001162135A (ja) * | 1999-12-10 | 2001-06-19 | Mitsubishi Heavy Ind Ltd | 水銀除去方法 |
KR20020044537A (ko) * | 2000-12-05 | 2002-06-15 | 로버트 제이. 에드워즈 | 원소형 수은 배출의 제어 방법 |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20160002952A (ko) * | 2013-04-26 | 2016-01-08 | 사노피 | 5-클로로-티오펜-2-카복실산 [(s)-2-[메틸-3-(2-옥소-피롤리딘-1-일)-벤젠설포닐아미노]-3-(4-메틸 피페라진-1-일)-3-옥소-프로필]아미드의 타르트레이트 염 |
JP2016518381A (ja) * | 2013-04-26 | 2016-06-23 | サノフイ | 5−クロロ−チオフェン−2−カルボン酸[(s)−2−[メチル−3−(2−オキソ−ピロリジン−1−イル)−ベンゼンスルホニルアミノ]−3−(4−メチル−ピペラジン−1−イル)−3−オキソ−プロプリル]アミドの酒石酸塩 |
KR102388926B1 (ko) | 2013-04-26 | 2022-04-22 | 베이징 리앤신 파마수티컬 씨오., 엘티디. | 5-클로로-티오펜-2-카복실산 [(s)-2-[메틸-3-(2-옥소-피롤리딘-1-일)-벤젠설포닐아미노]-3-(4-메틸 피페라진-1-일)-3-옥소-프로필]아미드의 타르트레이트 염 |
Also Published As
Publication number | Publication date |
---|---|
KR100953535B1 (ko) | 2010-04-21 |
KR20100008952A (ko) | 2010-01-27 |
US20110052468A1 (en) | 2011-03-03 |
JP4733784B2 (ja) | 2011-07-27 |
CN101939082A (zh) | 2011-01-05 |
US8017096B2 (en) | 2011-09-13 |
JP2011504805A (ja) | 2011-02-17 |
WO2010008253A3 (ko) | 2010-05-14 |
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