KR100270087B1 - Removal Method of Nitrogen Oxide Flue Gas Generated by Stainless Steel Mixed Acid Pickling Using Sulfamic Acid and Sulfuric Acid - Google Patents
Removal Method of Nitrogen Oxide Flue Gas Generated by Stainless Steel Mixed Acid Pickling Using Sulfamic Acid and Sulfuric Acid Download PDFInfo
- Publication number
- KR100270087B1 KR100270087B1 KR1019960068751A KR19960068751A KR100270087B1 KR 100270087 B1 KR100270087 B1 KR 100270087B1 KR 1019960068751 A KR1019960068751 A KR 1019960068751A KR 19960068751 A KR19960068751 A KR 19960068751A KR 100270087 B1 KR100270087 B1 KR 100270087B1
- Authority
- KR
- South Korea
- Prior art keywords
- acid
- pickling
- nox
- sulfuric acid
- hydrogen peroxide
- Prior art date
Links
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 title claims abstract description 104
- 238000005554 pickling Methods 0.000 title claims abstract description 68
- LNOPIUAQISRISI-UHFFFAOYSA-N n'-hydroxy-2-propan-2-ylsulfonylethanimidamide Chemical compound CC(C)S(=O)(=O)CC(N)=NO LNOPIUAQISRISI-UHFFFAOYSA-N 0.000 title claims abstract description 45
- 239000002253 acid Substances 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 title claims abstract description 20
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 title claims abstract description 15
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 14
- 239000010935 stainless steel Substances 0.000 title claims abstract description 14
- 239000003546 flue gas Substances 0.000 title abstract description 5
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title abstract 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 104
- 239000000654 additive Substances 0.000 claims abstract description 24
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 18
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 18
- 230000000694 effects Effects 0.000 claims description 17
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 12
- 239000007789 gas Substances 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 abstract description 22
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 238000005755 formation reaction Methods 0.000 abstract description 4
- 239000000243 solution Substances 0.000 description 14
- 230000000996 additive effect Effects 0.000 description 7
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 4
- 230000003111 delayed effect Effects 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 230000003746 surface roughness Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000012851 eutrophication Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910000358 iron sulfate Inorganic materials 0.000 description 1
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 235000021110 pickles Nutrition 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 208000023504 respiratory system disease Diseases 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000010626 work up procedure Methods 0.000 description 1
Classifications
-
- 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
- B01D47/00—Separating dispersed particles from gases, air or vapours by liquid as separating agent
-
- 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
- B01D53/77—Liquid phase processes
- B01D53/79—Injecting reactants
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/10—Oxidants
- B01D2251/106—Peroxides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/50—Inorganic acids
- B01D2251/506—Sulfuric acid
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
본 발명은 술파믹산과 황산을 이용하여 스테인레스강 혼산 산세 공정에서 발생하는 산화질소류 배가스를 효율적으로 제거하는 방법에 관한 것으로, 혼산 산세액에 술파믹산과 황산 첨가제를 1중량% 미만으로 첨가함으로써 산세조에서 NOx 생성을 과산화수소가 반응을 개시하기 전까지 지연한 다음 혼산 순환탱크에 과산화수소를 연속하여 첨가함으로써 생성된 NOx 배가스를 제거하는 방법을 제공한다.The present invention relates to a method for efficiently removing nitric oxide flue gas generated in a stainless steel mixed acid pickling process using sulfamic acid and sulfuric acid, wherein the acid pickling solution is added by adding less than 1% by weight of sulfamic acid and sulfuric acid additives. The tank provides a method for removing NOx flue-gases by delaying NOx production until hydrogen peroxide initiates the reaction and then continuously adding hydrogen peroxide to the mixed acid circulation tank.
본 발명은 술파믹산과 황산을 이용하여 초기 NOx 생성 반응을 지연한 다음 상기 술파믹산과 황산 첨가제의 효능이 감소한 후 생성된 NOx는 과산화수소와 반응시켜 최대 효율로 질산으로 제거·회수할 수 있다.In the present invention, after delaying the initial NOx formation reaction using sulfamic acid and sulfuric acid, the efficiency of the sulfamic acid and sulfuric acid additives is reduced, and the generated NOx may be removed and recovered as nitric acid at maximum efficiency by reacting with hydrogen peroxide.
Description
본 발명은 스테인레스강의 혼산 산세 공정에서 발생하는 산세 배가스중 산화질소류를 효율적으로 제거하는 방법에 관한 것이며, 보다 상세하게는 술파믹산과 황산을 이용하여 NOx 생성을 효과적으로 지연함으로써 산세시 발생하는 NOx 배가스를 효율적으로 제거하는 방법에 관한 것이다.The present invention relates to a method for efficiently removing nitrogen oxides from pickling flue gases generated in a mixed acid pickling process of stainless steel, and more particularly, NOx flue gases generated during pickling by effectively delaying NOx formation using sulfamic acid and sulfuric acid. It relates to a method for removing efficiently.
일반적으로 스테인레스강의 산세에는 질산과 불산을 적정비로 혼합한 혼산이 가장 산세성이 우수한 것으로 알려져 있고 또한 대부분 이러한 혼산을 사용하고 있다.In general, mixed acid obtained by mixing nitric acid and hydrofluoric acid in an appropriate ratio is known to have the best pickling property in stainless steel pickling, and most of these mixed acid are used.
그러나 상기 질산과 불산을 혼합한 혼산(이하, "혼산"이라 한다)은 산세시 NOx 가스를 발생하며 이는 완벽하게 처리하지 않은 채로 대기중에 방출되면 광화학 스모그의 전구 물질이 되기도 하고 대기중의 수분과 접촉하여 질산을 생성하여 산성비의 원인이 되기도 한다. 그외에도 호흡기 질환 및 하천과 해양을 부영양화하는 원인이 되므로 적조 현상을 초래하기도 한다.However, the mixed acid of nitric acid and hydrofluoric acid (hereinafter referred to as "mixed acid") generates NOx gas during pickling, which, when completely released into the atmosphere, becomes a precursor of photochemical smog and In contact, nitric acid may be produced, causing acid rain. In addition, respiratory diseases and eutrophication of rivers and oceans may cause red tide.
따라서 NOx를 제거하기 위한 여러 가지 방법이 개발되어 왔다. 최근에 Nicholas J. Rossi의 논문 "How to control NOx", Pollution Engineering, April 1995, pp 50-52, 미국 특허 제 4,938,838, 유럽 특허 제 0 267 166 A2 및 일본 특허 소 제60-243289, 소 61-15989, 소 57-19385 등의 공지된 기술에서 제시된 바와 같이 과산화수소, 술파믹산 및 요소를 이용한 NOx 제거 기술의 효과가 매우 우수한 것으로 평가되고 있다.Therefore, various methods for removing NOx have been developed. Recently published by Nicholas J. Rossi, "How to control NOx", Pollution Engineering, April 1995, pp 50-52, U.S. Patent 4,938,838, EP 0 267 166 A2 and Japanese Patent No. 60-243289, Sub 61- 15989, So 57-19385 and the like known in the known technology, the effect of the NOx removal technology using hydrogen peroxide, sulfamic acid and urea is evaluated to be very excellent.
그러나 과산화수소는 고가이므로 상기 기술은 경제적 측면에서 매우 열등하며, 이를 극복하기 위해서는 과산화수소의 사용량을 최소화하고 효율을 극대화할 수 있는 개선된 방법을 필요로 한다.However, because hydrogen peroxide is expensive, the technology is very inferior in terms of economics, and to overcome this, there is a need for an improved method of minimizing the amount of hydrogen peroxide used and maximizing efficiency.
과산화수소에 의한 효과를 향상시키기 위해서는 하기 반응식에서 알 수 있듯이 첨가된 과산화수소가 반응(2)를 일으키기 전에 반응(3)에 사용되도록 하여야 한다.In order to improve the effect by hydrogen peroxide, the added hydrogen peroxide must be used in the reaction (3) before the reaction (2), as can be seen in the following scheme.
즉 반응(4)가 일어나면 과산화수소가 비효율적으로 소비되며 또한 반응(2)가 반응(3)보다 빨리 일어나면 아질산이 질산으로 산화되기 전에 NOx 가스가 먼저 생성되며 일단 NOx가스가 생성되고 나면 제거하기가 어렵게 된다.In other words, when reaction (4) occurs, hydrogen peroxide is consumed inefficiently, and if reaction (2) occurs earlier than reaction (3), NOx gas is first generated before nitrous acid is oxidized to nitric acid, which is difficult to remove once NOx gas is generated. do.
4Fe + 10HNO3+ 8HF → 4FeF2 ++ 4NO3 -+ 6HNO2+6H2O (1) 4Fe + 10HNO 3 + 8HF → 4FeF 2 + + 4NO 3 - + 6HNO 2 + 6H 2 O (1)
2HNO2↔ N2O3+ H2O, N2O3↔ NO + NO2(2)2HNO 2 ↔ N 2 O 3 + H 2 O, N 2 O 3 ↔ NO + NO 2 (2)
HNO2+ H2O2→ HNO3+ H2O (3)HNO 2 + H 2 O 2 → HNO 3 + H 2 O (3)
H2O2→ H2O + 1/2 O2(4)H 2 O 2 → H 2 O + 1/2 O 2 (4)
그러므로 과산화수소를 사용하는 경우 가장 효율적인 방법은 산세되는 시점에서 적정량의 과산화수소가 존재하도록 하는 것이다. 즉 반응(1)의 산세가 일어난 직후 또는 반응(2)가 일어나기 전에 반응(3)이 일어남으로써 NOx가 생성되기 전에 아질산을 질산으로 산화시켜 질산을 재생시키고, 또한 반응(4)가 일어나기 전에 반응(3)이 일어남으로써 과산화수소의 소비를 방지하도록 전체 반응을 유도하는 것이 가장 효율적이라는 것을 본 발명의 주안점으로 착안하게 된 것이다.Therefore, the most efficient way to use hydrogen peroxide is to ensure that an adequate amount of hydrogen peroxide is present at the time of pickling. That is, nitrous acid is regenerated by nitric acid to regenerate nitric acid before reaction (3) takes place immediately after pickling of reaction (1) or before reaction (2) occurs, before NOx is produced, and also before reaction (4) takes place. As a result of (3), the main point of the present invention is that it is most efficient to induce the entire reaction to prevent the consumption of hydrogen peroxide.
그러나 스테인레스 산세 공장은 코일을 연속적으로 산세하고 산세조의 길이가 수십미터에 달하는 대형 공장이 대부분이기 때문에 산세되는 순간에 또는 코일의 상하면에 균일하게 적정량의 과산화수소를 연속적으로 첨가하기가 매우 곤란하다. 또한 산세 공장의 산세조 용량은 보통 10-40m3이며 여기에 과산화수소를 ppm 단위로 미소량을 첨가하기 때문에 침적식 산세조일 경우 과산화수소가 용액 표면에서 산세 표면까지 확산하여 도달하는 데는 약 1-20분 정도의 시간을 필요로 한다.However, since stainless steel pickling plants continuously pickle coils and most large plants have a length of several tens of meters, it is very difficult to continuously add an appropriate amount of hydrogen peroxide continuously at the time of pickling or at the top and bottom of the coil. In addition, the pickling tank capacity of the pickling plant is usually 10-40 m 3 , and a minute amount of hydrogen peroxide is added to the pickling plant. Therefore, in the case of an immersion pickling tank, hydrogen peroxide diffuses from the solution surface to the pickling surface to reach about 1-20 minutes. It needs time.
따라서 산세 용액 표면에 첨가된 과산화수소가 아질산이 생성되는 산세 표면까지 도달하기 전에 물과 산소로 분해되는 반응(4)가 일어나므로 과산화수소에 의한 NOx 제거 효율이 격감되게 된다.Therefore, before the hydrogen peroxide added to the pickling solution surface reaches the pickling surface where nitrous acid is generated, a reaction (4) occurs in which water and oxygen are decomposed, thereby reducing the NOx removal efficiency by hydrogen peroxide.
뿐만 아니라 혼산 산세액의 반응온도는 55-70℃인데 반해 35중량% 과산화수소는 약 35℃에서 분해한다. 따라서 과산화수소를 산세전에 첨가하는 것은 매우 비효율적이다.In addition, the reaction temperature of the mixed acid pickling solution is 55-70 ° C, whereas 35% by weight hydrogen peroxide decomposes at about 35 ° C. Therefore, it is very inefficient to add hydrogen peroxide before pickling.
이에 본 발명의 목적은 혼산 산세액에 술파믹산과 황산을 첨가하여 NOx 가스를 지연함으로써 산세액중 NOx 배가스를 효율적으로 제거하는 방법을 제공하는 것이다.Accordingly, an object of the present invention is to provide a method for efficiently removing NOx exhaust gas in an acid wash by adding sulfamic acid and sulfuric acid to the mixed acid wash to delay the NOx gas.
본 발명의 다른 목적은 상기 술파믹산과 황산을 첨가하여 초기 NOx 가스의 생성을 일정시간 지연한 다음 과산화수소를 연속 사용하여 술파믹산과 황산에 의한 지연효능이 감소한 다음 생성된 NOx 가스와 반응하여 산화질소를 질산으로 제거함과 동시에 질산을 회수하는 방법을 제공하는 것이다.Another object of the present invention is to delay the generation of the initial NOx gas by adding the sulfamic acid and sulfuric acid for a predetermined time and then to reduce the delay effect by the sulfamic acid and sulfuric acid by using hydrogen peroxide continuously and then react with the generated NOx gas and nitrogen oxide It is to provide a method for removing nitric acid and at the same time to recover the nitric acid.
제1도는 과산화수소, 술파믹산 및 황산의 함량 및 첨가 방법에 따른 NOx 지연 효과를 나타낸 그래프.1 is a graph showing the NOx retardation effect according to the content of hydrogen peroxide, sulfamic acid and sulfuric acid and the method of addition.
제2도는 혼산에 첨가하는 술파믹산과 황산 첨가제의 함량 변화에 따른 NOx 지연 효과를 나타낸 그래프이다.2 is a graph showing the NOx retardation effect according to the change in the amount of sulfamic acid and sulfuric acid additives added to the mixed acid.
본 발명은, 질산과 불산으로된 산세액을 함유하는 산세조에 술파믹산과 황산 첨가제를 1중량% 미만으로 첨가하고 상기 술파믹산과 황산이 첨가된 산세액으로 스테인레스강을 산세하면서 NOx 생성 반응을 과산화수소가 제거반응을 개시하기 전까지 지연하는 단계; 및 상기 지연 시간동안 산세조를 통과한 산세액에 산세량 혹은 NOx 생성량과 비례하여 연속적으로 과산화수소를 첨가함으로써 술파믹산과 황산에 의한 지연 효능이 감소한 다음 생성된 NOx 가스와 과산화수소가 반응하여 질산을 생성·회수하는 단계;를 포함하는 술파믹산과 황산을 이용한 스테인레스강 혼산 산세시 발생하는 산화질소류 배가스를 제거하는 방법에 관한 것이다.The present invention is to add a sulfuric acid and sulfuric acid additives in less than 1% by weight to a pickling bath containing a pickling solution of nitric acid and hydrofluoric acid, and the NOx formation reaction while pickling stainless steel with the pickling solution to which the sulfamic acid and sulfuric acid is added. Delaying until the removal reaction starts; And the hydrogen peroxide is continuously added to the pickling liquid passing through the pickling tank during the delay time in proportion to the amount of pickling or NOx production, thereby reducing the delay effect of sulfamic acid and sulfuric acid, and then reacting the generated NOx gas with hydrogen peroxide to produce nitric acid. It relates to a method for removing nitric oxide exhaust gas generated during the stainless steel mixed acid pickling using sulfamic acid and sulfuric acid, including the step of recovering.
이하 본 발명에 대하여 상세히 설명한다.Hereinafter, the present invention will be described in detail.
본 발명에서는 산세액에 혼산 산세 온도에서도 쉽게 분해하지 않는 술파믹산과 황산 첨가제를 첨가함으로써 과산화수소에 의한 NOx 제거 반응을 개시하기 전에 황산 및 스테인레스강내의 철이온과 황산이온과의 반응으로 생성된 황산철과 NOx를 1차적으로 반응하여 H2SO4·NO, NOHSO4, Fe(NO)SO4를 생성하며 산세 직후 급격히 NOx가 발생되는 것을 일시적으로 지연시키고 동시에 술파믹산을 NOx의 중간 생성물인 아질산과 반응하여 황산을 재생하고 산세 반응 및 환경에 무해한 질소 가스를 발생함으로써 황산을 단독으로 사용한 경우보다 초기 NOx 지연 반응을 배가시키는 것으로, 하기에 도식화하였다.In the present invention, the addition of sulfamic acid and sulfuric acid additives, which do not readily decompose at mixed acid pickling temperatures, to the pickling solution, the iron sulfate produced by the reaction of iron and sulfuric acid in sulfuric acid and stainless steel before initiating the NOx removal reaction by hydrogen peroxide. Reacts with NOx primarily to produce H 2 SO 4 · NO, NOHSO 4 , Fe (NO) SO 4 , and temporarily delays the rapid generation of NOx immediately after pickling, while sulfamic acid is reacted with nitrous acid, an intermediate of NOx The reaction was regenerated and the acid pickling reaction and generation of nitrogen gas harmless to the environment were shown below to double the initial NOx delayed reaction than when sulfuric acid was used alone.
NO + H2SO4→ H2SO4·NO (5) NO + H 2 SO 4 → H 2 SO 4 · NO (5)
N2O3+ 2H2SO4→ 2NOHSO4+ H2O (6)N 2 O 3 + 2H 2 SO 4 → 2NOHSO 4 + H 2 O (6)
NO + FeSO4→ Fe(NO)SO4(7)NO + FeSO 4 → Fe (NO) SO 4 (7)
NH2SO3H + HNO3→ H2SO4+ N2↑ + H2O (8)NH 2 SO 3 H + HNO 3 → H 2 SO 4 + N 2 ↑ + H 2 O (8)
상기 반응 생성물은 산세액에 침전물로 존재하게 되며 후처리 공정을 거쳐 슬러지로 배출된다.The reaction product is present as a precipitate in the pickling solution and discharged to the sludge after the work-up process.
스테인레스강 산세에는 질산 22중량% 및 불산 4중량%가 혼합된 혼산이 산세액으로 사용된다.For stainless steel pickling, mixed acid mixed with 22% by weight of nitric acid and 4% by weight of hydrofluoric acid is used as the pickling solution.
본 발명에서는 상기 일반적으로 사용되는 산세액에 술파믹산과 황산 첨가제를 1중량% 미만으로 첨가하게 된다. 상기 첨가제가 1중량% 이상 첨가되면 과량의 첨가제로 인해 혼산에서의 산세성 및 표면조도, 광택도 등의 표면물성이 열화한다.In the present invention, the sulfamic acid and sulfuric acid additives are added in an amount of less than 1% by weight to the generally used pickling solution. When the additive is added in an amount of 1% by weight or more, the excess of the additive deteriorates surface properties such as pickling properties and surface roughness and glossiness in mixed acid.
산세처리하고자 하는 스테인레스 강판을 혼산 순환 탱크로 부터 시편 표면에 술파믹산과 황산 첨가제가 1중량% 미만으로 첨가된 혼산 산세액이 일정 유량으로 흘러갈 수 있도록 설치한 산세 반응조를 이용하여 50-70℃의 혼산 산세 반응온도에서 산세하였다.The stainless steel plate to be pickled is 50-70 ° C using a pickling reactor installed so that the mixed acid pickling solution containing sulfamic acid and sulfuric acid additives of less than 1% by weight is flowed from the mixed acid circulation tank at a certain flow rate. Mixed acid pickling at Pickled at the reaction temperature.
산세시 혼산에 첨가된 술파믹산과 황산 첨가제에 의하여 초기 NOx 발생을 지연하는 동안 산세조를 통과한 산세액에 과산화수소를 연속적으로 첨가함으로써 술파믹산과 황산의 효능이 감소한 다음 생성된 NOx가 과산화수소와 반응하여 질산으로 제거되었고 질산은 회수하였다.The effect of sulfamic acid and sulfuric acid is reduced by continuously adding hydrogen peroxide to the pickling solution that has passed through the pickling bath while the initial NOx generation is delayed by the sulfamic acid and sulfuric acid additives added to the mixed acid during pickling, and then the generated NOx reacts with the hydrogen peroxide. Nitric acid was removed and nitric acid was recovered.
상기 과산화수소의 함량은 산세량(단위시간당 산세표면적) 및 NOx 생성량에 비례하여 첨가하였다.The hydrogen peroxide content was added in proportion to the pickling amount (pickling surface area per unit time) and the NOx production amount.
본 발명은 술파믹산과 황산 첨가제를 이용하여 초기 NOx 생성 반응을 지연한 다음 상기 술파믹산과 황산 첨가제의 NOx 지연효능이 감소한 후 생성된 NOx를 과산화수소와 반응시켜 최대 효율로 질산으로 제거·회수할 수 있었다.According to the present invention, after delaying the initial NOx formation reaction using sulfamic acid and sulfuric acid additives, the NOx delaying effect of the sulfamic acid and sulfuric acid additives is reduced, and the generated NOx is reacted with hydrogen peroxide to remove and recover nitric acid with maximum efficiency. there was.
이하, 실시예를 통하여 본 발명을 상세히 설명한다.Hereinafter, the present invention will be described in detail through examples.
[실시예 1]Example 1
과산화수소, 술파믹산 및 황산의 함량 및 주입 방법에 따른 NOx 제거 효과Effects of NOx Removal by Contents of Hydrogen Peroxide, Sulfamic Acid and Sulfuric Acid and Injection Methods
본 실험은 과산화수소, 술파믹산 및 황산의 주입 방법에 따른 NOx 제거 효과를 보기 위한 것으로, 종래의 방법에 의하여 첨가제는 전혀 첨가하지 않고 스테인레스강을 산세처리한 실시예 (가), 변형된 종래 방법으로 술파믹산과 황산 첨가제는 첨가하지 않고 과산화수소를 산세후 연속첨가한 실시예 (나), 종래의 방법으로 과산화수소를 일시에 산세조에 투입한 실시예 (다) 및 본 발명의 방법에 의하여 술파믹산과 황산 첨가제를 첨가한 다음 과산화수소를 혼산 순환 탱크에 연속 첨가한 실시예(라)에 대하어 NOx 제거율을 측정하고 그 결과를 제1도에 나타내었다.This experiment is to see the NOx removal effect according to the injection method of hydrogen peroxide, sulfamic acid and sulfuric acid. Example of the pickling treatment of stainless steel without adding any additives by the conventional method (A), the modified conventional method Example (b) in which hydrogen peroxide was continuously added after pickling without addition of sulfamic acid and sulfuric acid additives, Example (c) in which hydrogen peroxide was added to a pickling bath at a time by a conventional method, and by the method of the present invention, sulfamic acid and sulfuric acid The removal rate of NOx was measured for Example (d) in which hydrogen peroxide was continuously added to the mixed acid circulation tank after the addition of the additive, and the result is shown in FIG.
105mm × 170mm의 스테인레스 시편(STS304)을 산세 반응조에 장착하고 40L의 혼산순환탱크로 부터 시편 표면에 산세액이 일정 유량으로 흘러가도록 하였다.A 105 mm × 170 mm stainless specimen (STS304) was mounted in a pickling reactor and the pickling solution flowed at a constant flow rate from the 40 L mixed acid circulation tank to the specimen surface.
산세도중 발생하는 NOx는 NOx 측정기를 통해 1분 간격으로 11O분간 측정하고 그 값을 컴퓨터에 자동입력하였다. NOx측정기는 오존을 이용하여 NO2를 산화한 다음 NO2센서를 사용하는 것으로, 측정되는 NOx 제거율을 ppm단위로 표시하였다.NOx generated during pickling was measured for 11 minutes at 1 minute intervals using a NOx meter and the value was automatically entered into the computer. The NOx analyzer oxidizes NO 2 using ozone and then uses a NO 2 sensor, and indicates the measured NOx removal rate in ppm.
실시예 (가)의 경우 첨가제를 전혀 첨가하지 않고 스테인레스강을 산세시킨 다음 NOx 제거율을 측정한 비교예이다. 제1도에서 보듯이 산세 시작과 동시에 약 6,500㎎/㎥의 NOx가 발생되었다.Example (A) is a comparative example in which the NOx removal rate was measured after pickling stainless steel without adding any additives. As shown in FIG. 1, about 6,500 mg / m 3 of NOx was generated at the same time as pickling began.
실시예 (나)는 술파믹산과 황산 첨가제는 첨가하지 않고 과산화수소를 혼산 순환탱크에 연속하여 첨가하였다. NOx 제거율을 측정한 결과 산세 초반부에 발생한 약 4,000㎎/㎥의 NOx를 과산화수소가 제거하지 못하였고 과산화수소를 첨가하는 도중에도 약 500ppm 정도가 잔류하였으며 과산화수소를 중단한 다음에 발생한 NOx는 약 6,500㎎/㎥ 였다.In Example (b), hydrogen peroxide was continuously added to the mixed acid circulation tank without the addition of sulfamic acid and sulfuric acid additives. As a result of measuring NOx removal rate, hydrogen peroxide could not remove about 4,000mg / ㎥ of NOx generated at the beginning of pickling, and about 500ppm remained during hydrogen peroxide addition, and NOx generated after stopping hydrogen peroxide was about 6,500mg / ㎥ It was.
실시예 (다)는 종래의 방법에 의한 비교예로 연속 첨가할 과산화수소(1.6㎖/분 × 77분 =123㎖)을 산세전에 일시에 첨가하고 술파믹산 및 황산은 첨가하지 않았다.Example (C) was a comparative example by a conventional method, and hydrogen peroxide (1.6 mL / min x 77 min = 123 mL) to be added continuously was added at a time before pickling, and no sulfamic acid and sulfuric acid were added.
초기 30분간은 완벽하게 NOx 생성을 지연하는 듯하였으나 이후에 NOx가 급격하게 생성되었다. 과산화수소를 중단한 다음 발생된 NOx량은 약 6,500㎎/㎥였다.The initial 30 minutes seemed to completely delay the NOx production, but after that the NOx produced rapidly. The amount of NOx produced after stopping hydrogen peroxide was about 6,500 mg / m 3.
실시예 (라)는 22중량%의 질산과 4중량%의 불산을 혼합한 스테인레스강 혼산 산세액에 산세전에 술파믹산과 황산을 각각 0.5중량%썩 첨가하고 NOx를 지연한 다음 술파믹산과 황산에 의한 NOx 지연 효능이 남아 있는 동안에 혼산 순환 탱크에 과산화수소를 분당 1.6㎖로 연속적으로 80분간 첨가하고 NOx를 제거하였다. 나아가 과산화수소를 첨가하지 않은 경우에 대하여도 NOx 발생량을 관찰하였다.Example (d) added 0.5 wt% of sulfamic acid and sulfuric acid to each of the stainless steel mixed acid pickling solution containing 22% by weight of nitric acid and 4% by weight of hydrofluoric acid, and delayed NOx and then added to sulfamic acid and sulfuric acid. Hydrogen peroxide was continuously added to the mixed acid circulation tank at 1.6 ml / min for 80 minutes while the NOx delaying effect was maintained and NOx was removed. Furthermore, the amount of NOx generated was also observed even when hydrogen peroxide was not added.
제1도에서 보듯이 산세 초반에 NOx가 발생하지 않을 뿐만 아니라 후반에 과산화수소를 첨가하는 동안에도 거의 완벽하게 생성된 NOx 가스를 지연하였으며 과산화수소를 중단한 다음에 약 6,500㎎/㎥의 NOx가 측정되었다.As shown in FIG. 1, NOx was not generated in the early stage of pickling but also delayed the NOx gas produced almost completely during the addition of hydrogen peroxide in the late stage, and about 6,500 mg / m3 of NOx was measured after stopping the hydrogen peroxide. .
따라서 본 발명의 방법에 의하면 술파믹산과 황산을 산세액에 첨가함으로써 과산화수소가 NOx와 반응을 개시하기 전까지 NOx 발생을 총분히 지연할 수 있었으며 과산화수소는 NOx 생성량과 비례하여 연속적으로 첨가하는 것이 효율적이었다.Therefore, according to the method of the present invention, by adding sulfamic acid and sulfuric acid to the pickling solution, it was possible to delay NOx generation until hydrogen peroxide started to react with NOx, and it was efficient to add hydrogen peroxide continuously in proportion to the NOx production amount.
[실시예 2]Example 2
혼산에 첨가하는 술파믹산과 황산 첨가제의 함량 변화에 따른 NOx 제거 효과 본 실시예는 첨가하는 술파믹산과 황산의 적정량을 결정하기 위한 시험으로 혼산산세액에 첨가제를 전혀 첨가하지 않은 실시예 (가), 황산을 1중량% 첨가한 실시예 (나), 술파믹산을 1중량% 첨가한 실시예 (다) 및 술파믹산과 황산을 각각 0.5중량%씩 첨가한 실시예(라)에 대하여 NOx 제거율을 측정하고 그 결과를 제2도에 나타내었다.Effect of NOx removal according to the change of sulfamic acid and sulfuric acid additives added to the mixed acid This Example is a test to determine the appropriate amount of the sulfamic acid and sulfuric acid to be added Example (A) The NOx removal rate was compared to Example (b) in which 1% by weight of sulfuric acid was added, Example (c) in which 1% by weight of sulfamic acid was added, and Example (d) in which 0.5% by weight of sulfamic acid and sulfuric acid were added, respectively. Measurements were made and the results are shown in FIG.
첨가제를 사용하지 않은 실시예 (가)의 경우 NOx 생성량을 500㎎/㎥까지 지연하는데 걸리는 시간은 1분 정도였으며, 황산을 1중량% 첨가한 (나)의 경우 지연 시간은 약 5분, 술파믹산을 1중량% 첨가한 (다)의 경우 지연 시간은 약 10분간, 그리고 황산과 술파믹산을 각각 0.5중량%씩 첨가한 (라)의 경우는 18분 정도였다.In the case of Example (A) without using an additive, the time required to delay NOx production amount to 500 mg / m 3 was about 1 minute, and in case of (B) with 1% by weight of sulfuric acid, the delay time was about 5 minutes, and sulfa In the case of (C) in which 1% by weight of mymic acid was added, the delay time was about 10 minutes, and in the case of (D) in which 0.5% by weight of sulfuric acid and sulfamic acid were added, respectively, about 18 minutes.
상기 시험 결과로 부터 황산보다 술파믹산이 NOx 지연 효과가 양호하였으며 특히 술파믹산과 황산을 혼합하여 사용한 경우에 가장 NOx 지연 효과가 우수한 것으로 나타났다.From the above test results, sulfamic acid showed better NOx retardation effect than sulfuric acid, and especially when the mixture of sulfamic acid and sulfuric acid was used, the NOx retardation effect was excellent.
이는 상기 반응식 (5)-(8)에서 알 수 있듯이 술파믹산이 NOx의 중간 생성물인 아질산을 분해하여 질소를 발생하고 황산을 재생함으로써 NOx 억제에 이중 효과를 나타내기 때문이다.This is because sulfamic acid has a dual effect on NOx inhibition by decomposing nitrous acid, which is an intermediate product of NOx, generating nitrogen and regenerating sulfuric acid, as shown in the above Reactions (5)-(8).
한편 상기 첨가제 함량이 많을수록 초기 NOx 생성이 지연되는 효과는 비례함을 알수 있다. 그러나 첨가제가 과량이면 산세성 및 표면조도, 광택도 등과 같은 표면품질이 열화하는 관계로 첨가제의 총량은 1중량%를 기준하였다.On the other hand, as the additive content increases, the effect of delaying the initial NOx production can be seen to be proportional. However, if the additive is excessive, the surface quality such as pickling, surface roughness, glossiness, etc. deteriorates, so the total amount of the additive is based on 1 wt%.
본 발명의 방법에 의하면 과산화수소를 사용하여 NOx와 반응하기 전에 술파믹산과 황산으로 하여금 산세시 발생하는 초기 NOx를 지연하게 함으로써 NOx 생성을 과산화수소의 반응개시전까지 지연시키고 과산화수소를 연속적으로 첨가함으로써 술파믹산과 황산 첨가제에 의한 NOx 지연 효능이 감소한 다음 생성된 NOx와 과산화수소를 반응시켜 혼산 산세시 발생하는 NOx를 최대 효율로 질산으로 제거·회수할 수 있었다.According to the method of the present invention, before reacting with NOx using hydrogen peroxide, sulfamic acid and sulfuric acid delay the initial NOx generated during pickling, thereby delaying NOx production until the start of the reaction of hydrogen peroxide, and continuously adding hydrogen peroxide to the sulfamic acid and The NOx retardation effect of the sulfuric acid additives was reduced, and then the produced NOx and hydrogen peroxide were reacted to remove and recover NOx generated during mixed acid pickling with nitrate at maximum efficiency.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019960068751A KR100270087B1 (en) | 1996-12-20 | 1996-12-20 | Removal Method of Nitrogen Oxide Flue Gas Generated by Stainless Steel Mixed Acid Pickling Using Sulfamic Acid and Sulfuric Acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019960068751A KR100270087B1 (en) | 1996-12-20 | 1996-12-20 | Removal Method of Nitrogen Oxide Flue Gas Generated by Stainless Steel Mixed Acid Pickling Using Sulfamic Acid and Sulfuric Acid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| KR19980049999A KR19980049999A (en) | 1998-09-15 |
| KR100270087B1 true KR100270087B1 (en) | 2000-10-16 |
Family
ID=19489622
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1019960068751A KR100270087B1 (en) | 1996-12-20 | 1996-12-20 | Removal Method of Nitrogen Oxide Flue Gas Generated by Stainless Steel Mixed Acid Pickling Using Sulfamic Acid and Sulfuric Acid |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR100270087B1 (en) |
-
1996
- 1996-12-20 KR KR1019960068751A patent/KR100270087B1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| KR19980049999A (en) | 1998-09-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5985223A (en) | Removal of NOx and SOx emissions form pickling lines for metal treatment | |
| CA2312652C (en) | Reduction of toxic substances in waste gas emissions | |
| AU2003275051B2 (en) | Process for reducing the level of NOx in waste gas streams using sodium chlorite | |
| US3991167A (en) | Process for lowering nitrogen oxides in effluent gases | |
| US4400362A (en) | Removal of nitrogen oxides from gas | |
| KR100270087B1 (en) | Removal Method of Nitrogen Oxide Flue Gas Generated by Stainless Steel Mixed Acid Pickling Using Sulfamic Acid and Sulfuric Acid | |
| KR100306153B1 (en) | Stainless steel pickling method using urea and sulfuric acid to remove nitrogen oxide exhaust gas and improve surface properties | |
| Buck et al. | NOX removal in the stainless steel pickling industry with hydrogen peroxide | |
| KR19980051212A (en) | Removal Method of Nitric Oxide Flue Gas Generated by Pickling Stainless Steel Mixed Acid Using Sulfuric Acid | |
| CN111359398A (en) | Method for denitration and whitening of flue gas | |
| TW200835546A (en) | Method for purifying nitrous gas containing waste gas | |
| JP7537863B2 (en) | Denitration equipment and method | |
| JPH02214524A (en) | Nitrogen oxide removal method | |
| SU1106530A1 (en) | Method of removing nitric oxide from effluent gas | |
| JPS5889987A (en) | Treatment for purification of waste water after desulfurization and denitration | |
| JPS581616B2 (en) | Denitrification reaction tower | |
| JPS62262729A (en) | Method for removing nitrogen oxide contained in exhaust gas | |
| KR100609351B1 (en) | Simultaneous Deodorization and Denitrification of Chemical Refining Facilities | |
| JPH0526526B2 (en) | ||
| JPS6136447B2 (en) | ||
| CN110013761A (en) | A kind of deep purifying fine de-sulfur denitrating technique | |
| JPS5823135B2 (en) | Chitsusosankabutsujiyokiyohouhou | |
| JP2003117568A (en) | Method and apparatus for treating nitrogen compound-containing water | |
| JPH0471618A (en) | Treatment of gaseous nox | |
| JPS5949048B2 (en) | Wet treatment method for exhaust gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PA0109 | Patent application |
Patent event code: PA01091R01D Comment text: Patent Application Patent event date: 19961220 |
|
| A201 | Request for examination | ||
| PA0201 | Request for examination |
Patent event code: PA02012R01D Patent event date: 19980729 Comment text: Request for Examination of Application Patent event code: PA02011R01I Patent event date: 19961220 Comment text: Patent Application |
|
| PG1501 | Laying open of application | ||
| E701 | Decision to grant or registration of patent right | ||
| PE0701 | Decision of registration |
Patent event code: PE07011S01D Comment text: Decision to Grant Registration Patent event date: 20000707 |
|
| GRNT | Written decision to grant | ||
| PR0701 | Registration of establishment |
Comment text: Registration of Establishment Patent event date: 20000727 Patent event code: PR07011E01D |
|
| PR1002 | Payment of registration fee |
Payment date: 20000728 End annual number: 3 Start annual number: 1 |
|
| PG1601 | Publication of registration | ||
| FPAY | Annual fee payment |
Payment date: 20030701 Year of fee payment: 4 |
|
| PR1001 | Payment of annual fee |
Payment date: 20030701 Start annual number: 4 End annual number: 4 |
|
| LAPS | Lapse due to unpaid annual fee | ||
| PC1903 | Unpaid annual fee |
Termination category: Default of registration fee Termination date: 20050409 |