JP4329573B2 - Exhaust gas desulfurization method - Google Patents
Exhaust gas desulfurization method Download PDFInfo
- Publication number
- JP4329573B2 JP4329573B2 JP2004060462A JP2004060462A JP4329573B2 JP 4329573 B2 JP4329573 B2 JP 4329573B2 JP 2004060462 A JP2004060462 A JP 2004060462A JP 2004060462 A JP2004060462 A JP 2004060462A JP 4329573 B2 JP4329573 B2 JP 4329573B2
- Authority
- JP
- Japan
- Prior art keywords
- activated carbon
- exhaust gas
- carbon catalyst
- desulfurization
- gas desulfurization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000006477 desulfuration reaction Methods 0.000 title claims description 151
- 230000023556 desulfurization Effects 0.000 title claims description 151
- 238000000034 method Methods 0.000 title claims description 35
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 244
- 239000007789 gas Substances 0.000 claims description 205
- 239000003054 catalyst Substances 0.000 claims description 140
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 86
- 239000003546 flue gas Substances 0.000 claims description 86
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 76
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 claims description 60
- 229910000037 hydrogen sulfide Inorganic materials 0.000 claims description 59
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 54
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 claims description 35
- 239000005871 repellent Substances 0.000 claims description 21
- 239000007864 aqueous solution Substances 0.000 claims description 18
- 229920005989 resin Polymers 0.000 claims description 18
- 239000011347 resin Substances 0.000 claims description 18
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 14
- 229910052760 oxygen Inorganic materials 0.000 claims description 14
- 239000001301 oxygen Substances 0.000 claims description 14
- 238000002485 combustion reaction Methods 0.000 claims description 8
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims description 6
- 239000000243 solution Substances 0.000 claims description 5
- -1 and fluororesin Substances 0.000 claims description 4
- 238000005406 washing Methods 0.000 claims description 4
- 230000006866 deterioration Effects 0.000 claims description 3
- 239000004743 Polypropylene Substances 0.000 claims description 2
- 229920013716 polyethylene resin Polymers 0.000 claims description 2
- 229920001155 polypropylene Polymers 0.000 claims description 2
- 239000002994 raw material Substances 0.000 claims description 2
- 239000000779 smoke Substances 0.000 claims 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 9
- AKEJUJNQAAGONA-UHFFFAOYSA-N sulfur trioxide Chemical compound O=S(=O)=O AKEJUJNQAAGONA-UHFFFAOYSA-N 0.000 description 8
- 230000007423 decrease Effects 0.000 description 7
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 239000011148 porous material Substances 0.000 description 5
- 238000004140 cleaning Methods 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical class C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 230000002940 repellent Effects 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000000295 fuel oil Substances 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000007865 diluting Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 238000004898 kneading Methods 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000011162 core material Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- XUCNUKMRBVNAPB-UHFFFAOYSA-N fluoroethene Chemical group FC=C XUCNUKMRBVNAPB-UHFFFAOYSA-N 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000008235 industrial water Substances 0.000 description 1
- 239000012784 inorganic fiber Substances 0.000 description 1
- 239000003350 kerosene Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005504 petroleum refining Methods 0.000 description 1
- 229920005594 polymer fiber Polymers 0.000 description 1
- 229920001021 polysulfide Polymers 0.000 description 1
- 239000005077 polysulfide Substances 0.000 description 1
- 150000008117 polysulfides Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 229930192474 thiophene Natural products 0.000 description 1
- 150000003577 thiophenes Chemical class 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
Description
本発明は、亜硫酸ガスを含有する排ガスと排煙脱硫用活性炭触媒とを接触させ、該亜硫酸ガスを硫酸として回収除去する排ガス脱硫方法に関する。 The present invention relates to an exhaust gas desulfurization method in which an exhaust gas containing sulfurous acid gas is contacted with an activated carbon catalyst for flue gas desulfurization, and the sulfurous acid gas is recovered and removed as sulfuric acid.
火力発電所用ボイラーなどから排出される多量の燃焼排ガス中には、有毒な亜硫酸ガスが含まれている場合がある。そのような排ガス中から亜硫酸ガスを除去するために、活性炭触媒を用いて、亜硫酸ガスを硫酸として回収する排煙脱硫方法が提案されている（特許文献１〜４）。このような排煙脱硫方法においては、活性炭触媒が充填された触媒充填塔に排ガスを導入し、排ガス中の亜硫酸ガスを活性炭触媒上で排ガス中の酸素ガスにより接触酸化させて三酸化硫黄としている。この三酸化硫黄は、排ガス中の水分と反応して更に硫酸に変換され、活性炭触媒に吸着保持される。そして、活性炭触媒に保持できなくなった硫酸が、活性炭触媒から重力により離脱し、触媒充填塔下部において回収されることとなる。 Toxic sulfurous acid gas may be contained in a large amount of combustion exhaust gas discharged from boilers for thermal power plants. In order to remove sulfurous acid gas from such exhaust gas, flue gas desulfurization methods have been proposed in which sulfurous acid gas is recovered as sulfuric acid using an activated carbon catalyst (Patent Documents 1 to 4). In such a flue gas desulfurization method, exhaust gas is introduced into a catalyst packed tower packed with an activated carbon catalyst, and sulfurous acid gas in the exhaust gas is contact-oxidized with oxygen gas in the exhaust gas on the activated carbon catalyst to form sulfur trioxide. . This sulfur trioxide reacts with moisture in the exhaust gas and is further converted into sulfuric acid, and is adsorbed and held on the activated carbon catalyst. Then, the sulfuric acid that can no longer be held by the activated carbon catalyst is separated from the activated carbon catalyst by gravity and collected at the lower part of the catalyst packed tower.
ところで、火力発電所用ボイラーで燃焼させる燃料として重油が用いられているが、重油を燃料として使用する前に、その中に含有されているメルカプタン類やチオフェン類などの全イオウ成分を水素を用いて硫化水素に還元し、更にクラウス反応を利用し元素状硫黄として回収（水素化脱硫処理）することが、大気汚染を防止する観点から必須となっている。このような水素化脱硫処理は、重油に限らず、軽質油、灯油や軽油等に対しても必要となっている。ここで、このような水素化脱硫処理のオフガスには、硫化水素が含まれているため、オフガスをインシネレーターで燃焼処理して硫化水素を亜硫酸ガスに変換し、その亜硫酸ガスを含有するインシネレーターからの排ガスに対し、前述したような、活性炭触媒を使用する排煙脱硫処理を行うことが必要となる。 By the way, heavy oil is used as fuel to be burned in boilers for thermal power plants, but before using heavy oil as fuel, all sulfur components such as mercaptans and thiophenes contained therein are used with hydrogen. From the viewpoint of preventing air pollution, it is essential to reduce to hydrogen sulfide and then recover it as elemental sulfur (hydrodesulfurization treatment) using the Claus reaction. Such hydrodesulfurization treatment is required not only for heavy oil but also for light oil, kerosene, light oil and the like. Here, since the off-gas of such hydrodesulfurization treatment contains hydrogen sulfide, the off-gas is combusted by an incinerator to convert the hydrogen sulfide into sulfurous acid gas, and the sulfur dioxide gas containing the sulfurous acid gas. It is necessary to perform the flue gas desulfurization treatment using the activated carbon catalyst as described above on the exhaust gas from the synerator.
しかしながら、水素化脱硫処理オフガスをインシネレーターで燃焼処理して硫化水素ガスを亜硫酸ガスに変換した場合、燃焼処理が完全であれば、得られる排ガス中に硫化水素ガスが混入しないはずであるが、燃焼温度低下、酸素不足等のために排ガス中に硫化水素ガスが混入することが有り得る。活性炭触媒を使用する排煙脱硫の際に、処理すべき排ガス中に硫化水素ガスが混入した場合、元素状硫黄、ポリサルファイド、あるいはポリチオン酸が活性炭触媒上に蓄積しやすくなり、一旦蓄積すると活性炭触媒の脱硫性能が低下するという問題がある。 However, when the hydrodesulfurization treatment off-gas is combusted with an incinerator and the hydrogen sulfide gas is converted to sulfurous acid gas, if the combustion treatment is complete, hydrogen sulfide gas should not be mixed into the obtained exhaust gas. In addition, hydrogen sulfide gas may be mixed into the exhaust gas due to a decrease in combustion temperature, lack of oxygen, and the like. In the case of flue gas desulfurization using an activated carbon catalyst, if hydrogen sulfide gas is mixed in the exhaust gas to be treated, elemental sulfur, polysulfide, or polythionic acid tends to accumulate on the activated carbon catalyst, and once accumulated, the activated carbon catalyst There is a problem that the desulfurization performance of the steel is lowered.
最近、硫化水素ガスの除去に関し、硫化水素ガスを含有する空気を粒状活性炭や活性炭素繊維に接触させ、硫化水素ガスを硫酸に変換して除去することが報告されている（非特許文献１）。 Recently, with regard to the removal of hydrogen sulfide gas, it has been reported that air containing hydrogen sulfide gas is brought into contact with granular activated carbon or activated carbon fiber, and the hydrogen sulfide gas is converted to sulfuric acid to be removed (Non-patent Document 1). .
しかしながら、非特許文献１で使用した硫化水素ガスを含有する空気の酸素濃度は２１容量％であり、一方、燃焼排ガスの場合には、酸素濃度は１５容量％以下であり、酸素濃度の点で大きく相違する。また、非特許文献１で使用した硫化水素ガスを含有する空気には、亜硫酸ガスが含まれていないが、一方、排ガスの場合には、亜硫酸ガスを多量に含有しており、亜硫酸ガスの存在の有無の点でも相違する。しかも、硫化水素ガスと亜硫酸ガスとが共存する系では酸素濃度が相対的に低下するとクラウス反応により元素状硫黄が析出し易くなる。このため、非特許文献１の硫化水素ガスの除去技術は、亜硫酸ガスを含有する排ガスの排煙脱硫方法には適用できないと考えられていた。 However, the oxygen concentration of the air containing hydrogen sulfide gas used in Non-Patent Document 1 is 21% by volume. On the other hand, in the case of combustion exhaust gas, the oxygen concentration is 15% by volume or less. It is very different. The air containing hydrogen sulfide gas used in Non-Patent Document 1 does not contain sulfurous acid gas. On the other hand, in the case of exhaust gas, it contains a large amount of sulfurous acid gas and the presence of sulfurous acid gas. It is different also in the presence or absence of. Moreover, in a system in which hydrogen sulfide gas and sulfurous acid gas coexist, elemental sulfur is likely to precipitate due to the Claus reaction when the oxygen concentration is relatively lowered. For this reason, it was thought that the removal technique of the hydrogen sulfide gas of the nonpatent literature 1 is not applicable to the flue gas desulfurization method of the waste gas containing sulfurous acid gas.
本発明は、以上の従来の技術の問題を解決しようとするものであり、亜硫酸ガスと１５容量％以下の酸素とを含有する排ガスを、排煙脱硫用活性炭触媒と接触させることにより、排ガス中の亜硫酸ガスを硫酸として回収除去する排ガス脱硫方法において、排ガスが硫化水素ガスを含有していたとしても、排煙脱硫用活性炭触媒の脱硫性能を低下させないようにすることを目的とする。 The present invention is intended to solve the above-described problems of the conventional technology, and by contacting an exhaust gas containing sulfurous acid gas and 15% by volume or less of oxygen with an activated carbon catalyst for flue gas desulfurization, In the exhaust gas desulfurization method in which the sulfurous acid gas is recovered and removed as sulfuric acid, even if the exhaust gas contains hydrogen sulfide gas, the desulfurization performance of the activated carbon catalyst for flue gas desulfurization is not lowered.
本発明者は、硫化水素ガスに由来する元素状硫黄が排煙脱硫用活性炭触媒上に生成する時期について検討したところ、排煙脱硫用活性炭触媒が十分に湿潤していない状態の時期、即ち、排煙脱硫用活性炭触媒に初めて排ガスを接触させる際又は暫く排煙脱硫を中断した後に改めて排煙脱硫用活性炭触媒に排ガスを接触させる際に、元素状硫黄が排煙脱硫用活性炭触媒上に生成しやすいこと、逆に排煙脱硫用活性炭触媒が湿潤していると元素状硫黄が排煙脱硫用活性炭触媒上に生成し難いこと、さらに撥水化処理された排煙脱硫用活性炭は速やかに湿潤化できないために硫化水素による脱硫性能の低下が起きやすいこと、を見出し、本発明を完成させた。 The present inventor has examined the time when elemental sulfur derived from hydrogen sulfide gas is produced on the activated carbon catalyst for flue gas desulfurization, the time when the activated carbon catalyst for flue gas desulfurization is not sufficiently wet, that is, Elemental sulfur is generated on the flue gas desulfurization activated carbon catalyst when the flue gas desulfurization activated carbon catalyst is contacted with the exhaust gas for the first time or when the flue gas desulfurization is interrupted for a while and then the flue gas desulfurization activated carbon catalyst is contacted again. On the other hand, if the activated carbon catalyst for flue gas desulfurization is wet, elemental sulfur is difficult to form on the activated carbon catalyst for flue gas desulfurization. The inventors have found that the desulfurization performance is likely to deteriorate due to hydrogen sulfide because it cannot be wetted, and the present invention has been completed.
即ち、本発明は、亜硫酸ガスと１５容量％以下の酸素とを含有する排ガスを、活性炭と撥水性樹脂とを含む排煙脱硫用活性炭触媒と接触させることにより、排ガス中の亜硫酸ガスを硫酸として回収する排ガス脱硫方法において、該排ガスに混入する可能性のある硫化水素ガスによる該排煙脱硫用活性炭触媒の脱硫性能の低下を防止するために、該排ガスを該排煙脱硫用活性炭触媒に接触させる前に、該排煙脱硫用活性炭触媒を湿潤状態とすることを特徴とする排ガス脱硫方法を提供する。 That is, in the present invention, the sulfurous acid gas in the exhaust gas is converted into sulfuric acid by contacting the exhaust gas containing sulfurous acid gas and 15% by volume or less of oxygen with an activated carbon catalyst for flue gas desulfurization containing activated carbon and a water repellent resin. In the exhaust gas desulfurization method to be recovered, the exhaust gas is brought into contact with the flue gas desulfurization activated carbon catalyst in order to prevent deterioration of the desulfurization performance of the flue gas desulfurization activated carbon catalyst due to hydrogen sulfide gas that may be mixed into the exhaust gas. Provided is an exhaust gas desulfurization method characterized in that the activated carbon catalyst for flue gas desulfurization is brought into a wet state before being activated.
本発明の排ガス脱硫方法によれば、排ガスに硫化水素ガスが含有されていたとしても、元素状硫黄やポリチオン酸が排煙脱硫用活性炭触媒に付着しないようにすることができ、特に、排ガスを排煙脱硫用活性炭触媒に最初に接触させる際に起きる「排煙脱硫用活性炭触媒の脱硫性能の低下」を抑制することができ、長期に亘り安定して亜硫酸ガスを排ガスから除去することができる。 According to the exhaust gas desulfurization method of the present invention, elemental sulfur and polythionic acid can be prevented from adhering to the activated carbon catalyst for flue gas desulfurization even if hydrogen sulfide gas is contained in the exhaust gas. It is possible to suppress the “degradation of desulfurization performance of the activated carbon catalyst for flue gas desulfurization” that occurs when the activated carbon catalyst for flue gas desulfurization is first contacted, and to remove sulfurous acid gas from the exhaust gas stably over a long period of time. .
本発明の排ガス脱硫方法は、亜硫酸ガスと１５容量％以下の酸素とを含有する排ガスを、活性炭と撥水性樹脂とを含む排煙脱硫用活性炭触媒と接触させることにより、排ガス中の亜硫酸ガスを硫酸として回収する方法であり、該排ガスに混入する可能性のある硫化水素ガスによる該排煙脱硫用活性炭触媒の脱硫性能の低下を防止するために、該排ガスを該排煙脱硫用活性炭触媒に接触させる前に、該排煙脱硫用活性炭触媒を湿潤状態とすることを特徴とするものである。これにより、排ガス中に硫化水素ガスが混入したとしても、硫化水素ガスを原因とする排煙脱硫用活性炭触媒の脱硫性能の低下を抑制することができ、長期に亘り安定して亜硫酸ガスを排ガスから除去することができる。ここで、該排煙脱硫用活性炭触媒を排ガスと接触させる前とは、「未使用の排煙脱硫用活性炭触媒に初めて排ガスを接触させる前」、又は「排ガスを排煙脱硫用活性炭触媒に接触させた後に脱硫処理を中断し、その後に改めて排煙脱硫用活性炭触媒に排ガスを接触させる前」の両方の意味を含む。 In the exhaust gas desulfurization method of the present invention, an exhaust gas containing sulfurous acid gas and 15% by volume or less of oxygen is brought into contact with an activated carbon catalyst for flue gas desulfurization containing activated carbon and a water-repellent resin, whereby sulfurous acid gas in the exhaust gas is reduced. This is a method for recovering as sulfuric acid, and in order to prevent deterioration of the desulfurization performance of the activated carbon catalyst for flue gas desulfurization due to hydrogen sulfide gas that may be mixed into the exhaust gas, the exhaust gas is used as the activated carbon catalyst for flue gas desulfurization. Before the contact, the activated carbon catalyst for flue gas desulfurization is wetted. As a result, even if hydrogen sulfide gas is mixed in the exhaust gas, it is possible to suppress a decrease in the desulfurization performance of the activated carbon catalyst for flue gas desulfurization caused by the hydrogen sulfide gas, and to stably discharge the sulfurous acid gas over a long period of time. Can be removed. Here, before contacting the flue gas desulfurization activated carbon catalyst with the exhaust gas, "before contacting the exhaust gas for the first time with an unused flue gas desulfurization activated carbon catalyst" or "contacting the exhaust gas with the activated carbon catalyst for flue gas desulfurization" It includes both meanings of “before the desulfurization treatment is interrupted after the exhaust gas is exhausted and then the exhaust gas is again brought into contact with the activated carbon catalyst for flue gas desulfurization”.
本発明で使用する排煙脱硫用活性炭触媒は、亜硫酸ガスを含有する排ガスと接触したときに、該亜硫酸ガスを吸着し、酸化して、硫酸として回収除去するための触媒であり、活性炭と撥水性樹脂とを含む触媒である。このような排煙脱硫用活性炭触媒としては、繊維状活性炭、粒状活性炭、不織布状活性炭又はこれらを原料として加工された活性炭を、水に対する接触角が９０度以上を示す撥水性樹脂、例えば、テトラフルオロエチレン等のフッ素樹脂、ポリプロピレン樹脂、ポリエチレン樹脂もしくはこれらを含む撥水性樹脂で、撥水化処理したもの、例えば、繊維状もしくは粒子状活性炭と撥水性樹脂とを混合・混錬し、活性炭を撥水性樹脂に担持させたものを好ましく使用できる。更に、撥水性樹脂を補強部材として使用する場合でも撥水化処理効果が発現するのでより好ましい。排煙脱硫用活性炭触媒の具体例としては、活性炭粉末にフッ素樹脂粒子又はフッ素樹脂分散液を担持させて成形した活性炭触媒（特開平１０−３１４５８６号公報、請求項１〜５）、無機繊維や高分子繊維からなる芯材シートの両面に活性炭素繊維抄紙シートを積層した活性炭触媒（特開２０００−２６３６７８号公報）、活性炭粉末とフッ素樹脂とを剪断力を付加しながら混練して成形した活性炭触媒（特開平１１−２９０６８８号公報、請求項１〜６）、粒状活性炭に微細な撥水性物質を担持させた活性炭触媒の撥水化処理物（特開平１０−３１４５８５号公報、請求項１〜４）等を好ましく使用することができる。また、排煙脱硫用活性炭触媒は、ハニカム構造等のダストスルー構造に成形されたものを好ましく使用することができる。 The activated carbon catalyst for flue gas desulfurization used in the present invention is a catalyst for adsorbing and oxidizing the sulfurous acid gas when it comes into contact with the exhaust gas containing sulfurous acid gas, and recovering and removing it as sulfuric acid. A catalyst containing an aqueous resin. Examples of the activated carbon catalyst for flue gas desulfurization include fibrous activated carbon, granular activated carbon, nonwoven activated carbon, or activated carbon processed using these as raw materials, a water-repellent resin having a contact angle with water of 90 degrees or more, for example, tetra Fluorine resin such as fluoroethylene, polypropylene resin, polyethylene resin or water-repellent resin containing these, water-repellent treated, for example, mixing or kneading fibrous or particulate activated carbon and water-repellent resin, Those carried on a water-repellent resin can be preferably used. Furthermore, even when a water-repellent resin is used as a reinforcing member, it is more preferable because a water-repellent treatment effect is exhibited. Specific examples of the activated carbon catalyst for flue gas desulfurization include activated carbon catalyst (Japanese Patent Laid-Open No. 10-314586, claims 1 to 5) formed by supporting activated carbon powder with fluororesin particles or a fluororesin dispersion, inorganic fibers, Activated carbon catalyst (Japanese Patent Laid-Open No. 2000-263678) in which activated carbon fiber papermaking sheets are laminated on both sides of a core material sheet made of polymer fiber, activated carbon formed by kneading activated carbon powder and fluororesin while applying shearing force Catalyst (JP-A-11-290688, claims 1-6), water-repellent treated product of activated carbon catalyst in which fine activated water repellent material is supported on granular activated carbon (JP-A-10-314585, claims 1-6) 4) etc. can be used preferably. Moreover, as the activated carbon catalyst for flue gas desulfurization, a catalyst molded into a dust-through structure such as a honeycomb structure can be preferably used.
本発明の排ガス脱硫方法の対象となる、亜硫酸ガスを含有する排ガスとしては、硫化水素ガスが混入する可能性がある種々の燃焼排ガス等、例えば、硫化水素含有ガス中の硫化水素を亜硫酸ガスに変換するために、該硫化水素含有ガスを燃焼炉で燃焼させて得られる排ガスを対象とすることができる。従って、硫化水素ガスが常時混入した排ガスでも対象とすることができる。これは、本発明の排ガス脱硫方法においては、排ガスを排煙脱硫用活性炭触媒に接触させる前に、排煙脱硫用活性炭触媒を予め湿潤させておくことにより、排煙脱硫用活性炭触媒の脱硫性能に対する硫化水素ガスの悪影響を排除できるからである。排ガス中に硫化水素ガスが混入した場合、その許容濃度範囲は、多すぎると活性炭触媒を予め湿潤させておいても脱硫性能の低下を引き起こすので、５００ｐｐｍを超えないようにすることが好ましい。下限については、本来的に含有していないことが好ましいので特に制限はない。 As an exhaust gas containing sulfurous acid gas, which is an object of the exhaust gas desulfurization method of the present invention, various combustion exhaust gases that may contain hydrogen sulfide gas, for example, hydrogen sulfide in a hydrogen sulfide-containing gas is converted into sulfurous acid gas. In order to convert, exhaust gas obtained by burning the hydrogen sulfide-containing gas in a combustion furnace can be targeted. Therefore, even exhaust gas in which hydrogen sulfide gas is always mixed can be targeted. In the exhaust gas desulfurization method of the present invention, the desulfurization performance of the exhaust gas desulfurization activated carbon catalyst is obtained by previously moistening the exhaust gas desulfurization activated carbon catalyst before contacting the exhaust gas with the exhaust gas desulfurization activated carbon catalyst. This is because the adverse effect of hydrogen sulfide gas on the water can be eliminated. When the hydrogen sulfide gas is mixed in the exhaust gas, if the allowable concentration range is too large, desulfurization performance is deteriorated even if the activated carbon catalyst is wetted in advance. Therefore, it is preferable not to exceed 500 ppm. The lower limit is not particularly limited because it is preferably not inherently contained.
また、排ガス中の酸素濃度は、排ガス生成時に燃焼反応で酸素が消費されているので、１５容量％以下、場合により１０容量％以下であるが、酸素濃度が低すぎるとそもそも亜硫酸ガスを酸化できなくなるので、亜硫酸ガスの濃度にもよるが、０．５容量％を下回らないようにすることが好ましい。 Further, the oxygen concentration in the exhaust gas is 15% by volume or less and sometimes 10% by volume or less because oxygen is consumed in the combustion reaction when the exhaust gas is generated. However, if the oxygen concentration is too low, sulfur dioxide gas can be oxidized in the first place. Therefore, it is preferable not to fall below 0.5% by volume, although it depends on the concentration of sulfurous acid gas.
また、亜硫酸ガスは、活性炭触媒上で酸化されて三酸化硫黄となり、更に硫酸となるが、そのためには三酸化硫黄と反応する水が必要である。この水は、通常、排ガス中に含まれる水蒸気から供給されるが、不足する場合は脱硫系外から排煙脱硫用活性炭触媒に供給してもよい。また、この水としては、通常の工業用水、脱硫工程で生成した硫酸を含む希硫酸水溶液を好ましく使用することができる。 In addition, sulfurous acid gas is oxidized on the activated carbon catalyst to form sulfur trioxide and further to sulfuric acid. For this purpose, water that reacts with sulfur trioxide is required. This water is usually supplied from water vapor contained in the exhaust gas, but if it is insufficient, it may be supplied from outside the desulfurization system to the activated carbon catalyst for flue gas desulfurization. Moreover, as this water, the normal industrial water and the dilute sulfuric acid aqueous solution containing the sulfuric acid produced | generated by the desulfurization process can be used preferably.
本発明の排ガス脱硫方法においては、前述したように、硫化水素ガスによる該排煙脱硫用活性炭触媒の脱硫性能の低下を防止するために、排ガスを排煙脱硫用活性炭触媒に接触させる前に、排煙脱硫用活性炭触媒を湿潤状態とする。ここで、排煙脱硫用活性炭触媒の湿潤状態とは、排煙脱硫用活性炭触媒の水分含有量が好ましくは３０重量％以上、より好ましくは４０重量％以上となっている状態である。これは、排煙脱硫用活性炭触媒の水分含有量が３０重量％未満であると、水分の効果が小さく、排ガスに硫化水素が混入した場合に排煙脱硫用活性炭触媒の脱硫性能が急激に低下するという傾向があるためである。水分含有量の上限は触媒の細孔容積の関係から決まるが、通常は７０重量％程度であり、それ以上の場合は触媒表面を水分が覆い、その性能が低下する傾向があり好ましくない。なお、水分含有量の測定は排煙脱硫用活性炭触媒を１２０〜１２５℃で恒量になるまで乾燥することにより行う。 In the exhaust gas desulfurization method of the present invention, as described above, before the exhaust gas is brought into contact with the flue gas desulfurization activated carbon catalyst in order to prevent the desulfurization performance of the activated carbon catalyst for flue gas desulfurization due to hydrogen sulfide gas, The activated carbon catalyst for flue gas desulfurization is in a wet state. Here, the wet state of the activated carbon catalyst for flue gas desulfurization is a state where the moisture content of the activated carbon catalyst for flue gas desulfurization is preferably 30% by weight or more, more preferably 40% by weight or more. This is because the moisture content of the activated carbon catalyst for flue gas desulfurization is less than 30% by weight, and the desulfurization performance of the activated carbon catalyst for flue gas desulfurization decreases drastically when hydrogen sulfide is mixed into the exhaust gas. This is because there is a tendency to do. The upper limit of the water content is determined by the relationship between the pore volume of the catalyst, but is usually about 70% by weight. If it exceeds the upper limit, the catalyst surface is covered with water, and the performance tends to decrease, which is not preferable. The moisture content is measured by drying the activated carbon catalyst for flue gas desulfurization at 120 to 125 ° C. until it reaches a constant weight.
排煙脱硫用活性炭触媒を湿潤状態とするための具体的手段としては、温度３０℃以上の水もしくは硫酸水溶液、水蒸気、又は水蒸気を添加して増湿させた硫化水素ガス非含有ガスを排煙脱硫用活性炭触媒と接触させることが挙げられる。ここで、排煙脱硫用活性炭触媒に水もしくは硫酸水溶液を接触させる場合に、３０℃以上の温度のものを使用する理由は、撥水処理化した脱硫用活性炭触媒では、液状の水は細孔内に浸入しづらく、水蒸気の状態で細孔内に浸透、凝縮させる必要があるためである。そのために硫酸水溶液を使用する場合には撥水化処理した脱流用活性炭を湿潤させるのに必要な水蒸気圧を示す温度にする必要がある。たとえば５０重量％の硫酸水溶液を使用する場合には３０℃の水と同等な水蒸気圧を示す５０℃以上の温度のものを使用する必要がある。水蒸気を使用する場合には撥水処理に用いた撥水性樹脂が変質しない１５０℃以下の温度のものを使用することが好ましい。 As a specific means for bringing the activated carbon catalyst for flue gas desulfurization into a wet state, flue gas containing water or sulfuric acid aqueous solution having a temperature of 30 ° C. or higher, water vapor, or hydrogen sulfide gas-free gas that has been humidified by adding water vapor The contact with the activated carbon catalyst for desulfurization is mentioned. Here, when the activated carbon catalyst for flue gas desulfurization is brought into contact with water or a sulfuric acid aqueous solution, the reason for using a catalyst having a temperature of 30 ° C. or higher is that, in the activated carbon catalyst for desulfurization treated with water repellency, liquid water is pores. This is because it is difficult to penetrate into the pores and it is necessary to penetrate and condense into the pores in the state of water vapor. For this reason, when an aqueous sulfuric acid solution is used, it is necessary to set the temperature to indicate the water vapor pressure necessary for wetting the activated carbon for deflowing which has been made water repellent. For example, when a 50% by weight sulfuric acid aqueous solution is used, it is necessary to use one having a temperature of 50 ° C. or higher that exhibits a water vapor pressure equivalent to 30 ° C. water. When water vapor is used, it is preferable to use one having a temperature of 150 ° C. or less at which the water-repellent resin used for the water-repellent treatment does not change.
水蒸気を添加して増湿させた硫化水素ガス非含有ガスとしては、相対湿度を５０％以上に増湿させた、硫化水素ガスを含まない空気や排ガスを使用することができる。このような硫化水素ガス非含有ガスの温度は、活性炭触媒を湿潤させるに十分な水分を含有すべきである点及び撥水化処理に用いた撥水性樹脂の変質を防止する点から、好ましくは３０〜１５０℃である。中でも、排煙脱硫用活性炭触媒が撥水性樹脂により撥水性を示し、脱硫用活性炭触媒の外表面や細孔内を湿潤状態とすることが容易ではない点に鑑み、排煙脱硫用活性炭触媒を湿潤状態とするための好ましい具体的手段としては、ガス状の水である水蒸気を用いて排煙脱硫用活性炭触媒を湿潤状態とすることが好ましい。 As the hydrogen sulfide gas-free gas that has been humidified by adding water vapor, air or exhaust gas that does not contain hydrogen sulfide gas and has a relative humidity increased to 50% or more can be used. The temperature of such a hydrogen sulfide gas-free gas is preferably from the point that it should contain sufficient water to wet the activated carbon catalyst and to prevent alteration of the water-repellent resin used in the water-repellent treatment. 30 to 150 ° C. Among them, in view of the fact that the activated carbon catalyst for flue gas desulfurization exhibits water repellency by the water repellent resin and it is not easy to wet the outer surface and pores of the activated carbon catalyst for desulfurization, the activated carbon catalyst for flue gas desulfurization is As a preferable specific means for making the wet state, it is preferable to make the activated carbon catalyst for flue gas desulfurization wet by using water vapor which is gaseous water.
本発明の排ガス脱硫方法においては、前述のように湿潤させた排煙脱硫用活性炭触媒の湿潤状態を維持させながら、排煙脱硫用活性炭触媒に排ガスを接触させることが好ましい。これにより、排ガス脱硫方法の実施の開始時から終了時に至るまで排煙脱硫用活性炭触媒の脱硫性能の低下を防止することができる。 In the exhaust gas desulfurization method of the present invention, the exhaust gas is preferably brought into contact with the activated carbon catalyst for flue gas desulfurization while maintaining the wet state of the activated carbon catalyst for flue gas desulfurization as described above. Thereby, the fall of the desulfurization performance of the activated carbon catalyst for flue gas desulfurization can be prevented from the start to the end of the execution of the exhaust gas desulfurization method.
排煙脱硫用活性炭触媒の湿潤状態を維持するための手法の具体例としては、排ガス中の水蒸気分圧の調整を行うか、又は排煙脱硫用活性炭触媒に水もしくは硫酸水溶液による洗浄を行うことが挙げられる。ここで、排ガス中の水蒸気分圧の調整を行う場合、硫化水素ガスが排ガス中に存在し且つ相対湿度が低すぎると、長時間にわたり、排煙脱硫用活性炭触媒の脱硫性能が徐々に低下するため、排ガス中の水蒸気分圧を相対湿度５０％以上となるように調整することが好ましい。この場合、排ガス中の水蒸気分圧を温度１５０℃以下で相対湿度５０％以上となるように調整することが好ましい。１５０℃を超えると撥水化処理に用いた撥水性樹脂の変質を招くので、好ましくない。なお、排煙脱硫用活性炭触媒の湿潤状態を維持するために、排煙脱硫用活性炭触媒を水もしくは硫酸水溶液により洗浄を行っても、水蒸気を用いた場合よりは効率的ではないが、排煙脱硫用活性炭触媒の湿潤状態を向上させることができる。この場合、排煙脱硫用活性炭触媒を水又は硫酸水溶液で連続的に、間欠的に、又はワンスルーで洗浄することができる。更に、洗浄に使用した水又は硫酸水溶液を循環使用することもできる。 Specific examples of techniques for maintaining the wet state of the activated carbon catalyst for flue gas desulfurization include adjusting the partial pressure of water vapor in the exhaust gas, or washing the activated carbon catalyst for flue gas desulfurization with water or sulfuric acid aqueous solution. Is mentioned. Here, when adjusting the water vapor partial pressure in the exhaust gas, if hydrogen sulfide gas is present in the exhaust gas and the relative humidity is too low, the desulfurization performance of the activated carbon catalyst for flue gas desulfurization gradually decreases over a long period of time. Therefore, it is preferable to adjust the water vapor partial pressure in the exhaust gas so that the relative humidity is 50% or more. In this case, it is preferable to adjust the water vapor partial pressure in the exhaust gas so that the relative humidity is 50% or more at a temperature of 150 ° C. or less. If it exceeds 150 ° C., the water-repellent resin used for the water-repellent treatment is deteriorated, which is not preferable. In order to maintain the wet state of the activated carbon catalyst for flue gas desulfurization, cleaning the activated carbon catalyst for flue gas desulfurization with water or an aqueous sulfuric acid solution is less efficient than using steam, The wet state of the activated carbon catalyst for desulfurization can be improved. In this case, the activated carbon catalyst for flue gas desulfurization can be washed with water or a sulfuric acid aqueous solution continuously, intermittently or one-through. Furthermore, the water or sulfuric acid aqueous solution used for washing | cleaning can also be recycled.
また、本発明の排ガス脱硫方法においては、排ガスを排煙脱硫用活性炭触媒に接触させる前に、排ガス中の硫化水素ガス濃度を計測することが好ましい。硫化水素ガス濃度計測は公知の測定方法に従って行うことができる。硫化水素ガス濃度を計測することにより、排ガスの脱硫を行う際に、リアルタイムで排ガス中の硫化水素ガス濃度を把握することできる。従って、硫化水素ガス濃度に応じて、排煙脱硫用活性炭触媒の湿潤状態（水分含有量）のレベルの決定、あるいは湿潤状態とする手法の選択や、湿潤状態とする操作の頻度、操作の軽重を決定することができる。ここで、排ガス中の硫化水素ガス濃度が５０ｐｐｍ以下であれば、排ガス中の水蒸気分圧を相対湿度５０％以上にすることにより、排煙脱硫用活性炭触媒の脱硫性能の低下を防止できるが、排ガス中の硫化水素ガス濃度が５０ｐｐｍを超える場合には大幅な脱硫性能の低下が懸念される。従って、硫化水素ガス濃度が５０ｐｐｍ以上と検出された場合には、湿潤状態を高めるために、該ガス中の水蒸気分圧を相対湿度７０％以上に調整するか、及び／又は水もしくは硫酸水溶液で該排煙脱硫用活性炭触媒の洗浄を行うかもしくは洗浄に使用する水もしくは硫酸水溶液の量を増大させることが好ましい。洗浄液の量を増大させることは、水蒸気による触媒の水分含有量を速やかに高くする効果及び洗浄液の量が増大することによって触媒の表面を液膜で覆うことで一時的な硫化水素の流入による性能低下を抑制できる効果がある。 In the exhaust gas desulfurization method of the present invention, it is preferable to measure the hydrogen sulfide gas concentration in the exhaust gas before contacting the exhaust gas with the activated carbon catalyst for flue gas desulfurization. The hydrogen sulfide gas concentration measurement can be performed according to a known measurement method. By measuring the hydrogen sulfide gas concentration, the hydrogen sulfide gas concentration in the exhaust gas can be grasped in real time when the exhaust gas is desulfurized. Therefore, depending on the hydrogen sulfide gas concentration, the determination of the wet state (moisture content) level of the activated carbon catalyst for flue gas desulfurization, the selection of the method for making the wet state, the frequency of the operation to make the wet state, the weight of the operation Can be determined. Here, if the hydrogen sulfide gas concentration in the exhaust gas is 50 ppm or less, it is possible to prevent a decrease in the desulfurization performance of the activated carbon catalyst for flue gas desulfurization by making the water vapor partial pressure in the exhaust gas 50% or more, When the hydrogen sulfide gas concentration in the exhaust gas exceeds 50 ppm, there is a concern that the desulfurization performance will be significantly reduced. Therefore, when the hydrogen sulfide gas concentration is detected to be 50 ppm or more, in order to enhance the wet state, the water vapor partial pressure in the gas is adjusted to 70% or higher relative humidity and / or with water or a sulfuric acid aqueous solution. It is preferable to wash the activated carbon catalyst for flue gas desulfurization or increase the amount of water or sulfuric acid aqueous solution used for washing. Increasing the amount of cleaning liquid is effective for quickly increasing the moisture content of the catalyst due to water vapor, and the performance of the inflow of hydrogen sulfide by covering the surface of the catalyst with a liquid film by increasing the amount of cleaning liquid There is an effect of suppressing the decrease.
以下、本発明を実施例により具体的に説明する。 Hereinafter, the present invention will be specifically described by way of examples.
実施例１
粒状活性炭９０重量部に対し、ポリテトラフルオロチレン水分散液（樹脂固形分６０重量％）（ダイキン工業製）を固形分濃度で１０重量部になるように混合し、加圧ニーダーを用いて混練した後、ロールを用いて厚さ０．８ｍｍの平板状シートを作成した。この平板状シートの半量を歯車状ロールで波型に加工し、前記平板状シートと交合に積層することにより、ハニカム状の排煙脱硫用活性炭触媒を得た。
Example 1
To 90 parts by weight of granular activated carbon, a polytetrafluoroethylene aqueous dispersion (resin solid content 60% by weight) (manufactured by Daikin Industries) is mixed so as to have a solid content concentration of 10 parts by weight, and kneaded using a pressure kneader. Then, a flat sheet having a thickness of 0.8 mm was prepared using a roll. Half of the flat sheet was processed into a corrugated shape with a gear-shaped roll, and laminated with the flat sheet to obtain a honeycomb-shaped activated carbon catalyst for flue gas desulfurization.
得られたハニカム状の排煙脱硫用活性炭触媒を、５０ｍｍ角の断面形状を有する触媒充填塔等に高さが２０００ｍｍとなるように充填することにより触媒層を構成させた。この触媒層に対し、触媒充填塔内の上方から、約５０℃に加温した水をシャワーリングし、排煙脱硫用活性炭触媒を５０重量％の湿潤状態とした。 The obtained activated carbon catalyst for flue gas desulfurization was packed in a catalyst packed tower having a cross section of 50 mm square so as to have a height of 2000 mm to form a catalyst layer. The catalyst layer was showered with water heated to about 50 ° C. from above in the catalyst packed tower to make the activated carbon catalyst for flue gas desulfurization 50% by weight wet.
その湿潤状態となった触媒層に、酸素濃度５容量％、亜硫酸ガス濃度１０００ｐｐｍ、硫化水素ガス１０ｐｐｍ、炭酸ガス１０容量％及び残余窒素ガスからなる模擬排ガスを触媒と接触する前に水蒸気を加えて相対湿度８０％、温度５０℃として５ｍ3／時の流量で通過させた。１００時間後の脱硫率は９０％であり、８０００時間後（約１年後）の脱硫率は８６％であった。 Water vapor is added to the catalyst layer in a wet state before contacting the catalyst with a simulated exhaust gas comprising an oxygen concentration of 5 vol%, a sulfurous acid gas concentration of 1000 ppm, a hydrogen sulfide gas of 10 ppm, a carbon dioxide gas of 10 vol%, and a residual nitrogen gas. It was passed at a flow rate of 5 m 3 / hour at a relative humidity of 80% and a temperature of 50 ° C. The desulfurization rate after 100 hours was 90%, and the desulfurization rate after 8000 hours (about 1 year later) was 86%.
実施例２
実施例１と同様に、触媒充填塔に排煙脱硫用活性炭触媒を充填して触媒層で構成させた。この触媒層に対し、触媒充填塔内の上方から、約５０℃に加温した５ｗｔ％硫酸溶液を２４時間シャワーリングし、排煙脱硫用活性炭触媒を水分含有量５０重量％の湿潤状態とした。
Example 2
In the same manner as in Example 1, the catalyst packed tower was filled with the activated carbon catalyst for flue gas desulfurization and constituted with a catalyst layer. The catalyst layer was showered with a 5 wt% sulfuric acid solution heated to about 50 ° C. for 24 hours from above in the catalyst packed tower to make the activated carbon catalyst for flue gas desulfurization wet with a moisture content of 50% by weight. .
その湿潤状態となった触媒層に、酸素濃度５容量％、亜硫酸ガス濃度１０００ｐｐｍ、硫化水素ガス１０ｐｐｍ、炭酸ガス１０容量％及び残余窒素ガスからなる相対湿度６０％、温度５０℃の模擬排ガスを５ｍ3／時の流量で通過させた。なお、模擬排ガスを触媒層に通過させている間、脱硫によって生成した希硫酸を２倍に希釈した希硫酸水溶液を連続的に触媒層に循環通過させた。１００時間後の脱硫率は８７％であり、８０００時間後（約１年後）の脱硫率は約８３％であった。 5 m of simulated exhaust gas having a relative humidity of 60% and a temperature of 50 ° C. composed of 5% by oxygen concentration, 1000 ppm of sulfurous acid gas, 10 ppm of hydrogen sulfide gas, 10% by volume of carbon dioxide gas and residual nitrogen gas is placed on the wet catalyst layer. It was passed at a flow rate of 3 / hour. While the simulated exhaust gas was passed through the catalyst layer, a dilute sulfuric acid aqueous solution obtained by diluting diluted sulfuric acid generated by desulfurization twice was continuously circulated through the catalyst layer. The desulfurization rate after 100 hours was 87%, and the desulfurization rate after 8000 hours (after about one year) was about 83%.
実施例３
実施例１と同様に、触媒充填塔に排煙脱硫活性炭触媒を充填して触媒層を構成させた。この触媒層に対し、触媒充填塔の上方から、約５０℃に加温した５ｗｔ％硫酸水溶液を２４時間シャワーリングし、排煙脱硫用活性炭触媒を５０重量％の湿潤状態とした。
Example 3
As in Example 1, the catalyst packed tower was packed with the flue gas desulfurization activated carbon catalyst to form a catalyst layer. The catalyst layer was showered with a 5 wt% sulfuric acid aqueous solution heated to about 50 ° C. for 24 hours from the top of the catalyst packed tower to make the activated carbon catalyst for flue gas desulfurization 50% by weight wet.
その湿潤状態となった触媒層に、酸素濃度５容量％、亜硫酸ガス濃度１０００ｐｐｍ、炭酸ガス１０容量％及び残余窒素ガスからなる相対湿度８０％、温度５０℃の模擬排ガスを５ｍ3／時の流量で通過させた。なお、模擬排ガスを触媒層に通過させている間、脱硫によって生成した希硫酸を２倍に希釈した希硫酸水溶液を連続的に触媒層に循環通過させた。２００時間毎に硫化水素ガスを３００ｐｐｍの濃度で模擬排ガスに３０分間にわたり添加し、硫化水素ガス添加時には触媒層に循環通過させる希硫酸水溶液の流量を３倍に増加させた。１００時間後の脱硫率は８７％であり、８０００時間後（約１年後）の脱硫率は８４％であった。 A flow rate of 5 m 3 / h of simulated exhaust gas having an oxygen concentration of 5 vol%, a sulfurous acid gas concentration of 1000 ppm, a carbon dioxide gas of 10 vol% and a residual nitrogen gas of 80% relative humidity and a temperature of 50 ° C. is applied to the wet catalyst layer. It was passed through. While the simulated exhaust gas was passed through the catalyst layer, a dilute sulfuric acid aqueous solution obtained by diluting diluted sulfuric acid generated by desulfurization twice was continuously circulated through the catalyst layer. Every 200 hours, hydrogen sulfide gas was added to the simulated exhaust gas at a concentration of 300 ppm over 30 minutes, and when the hydrogen sulfide gas was added, the flow rate of the dilute sulfuric acid aqueous solution that was circulated through the catalyst layer was tripled. The desulfurization rate after 100 hours was 87%, and the desulfurization rate after 8000 hours (about 1 year later) was 84%.
比較例１
触媒層を湿潤状態としないこと以外は、実施例１と同様に模擬排ガスを触媒層に通過させた。その結果、１００時間後の脱硫率は７３％であり、１４００時間（約２ヶ月）後の脱硫率は６９％であった。
Comparative Example 1
Simulated exhaust gas was passed through the catalyst layer in the same manner as in Example 1 except that the catalyst layer was not wet. As a result, the desulfurization rate after 100 hours was 73%, and the desulfurization rate after 1400 hours (about 2 months) was 69%.
比較例２
硫化水素添加時に触媒層に循環する希硫酸水溶液の流量を増加させないこと以外は実施例３と同様な操作を行った。その結果、１００時間後の脱硫率は８７％であり、８０００時間（約１年後）の脱硫率は５１％であった。
Comparative Example 2
The same operation as in Example 3 was performed except that the flow rate of the dilute sulfuric acid aqueous solution circulating to the catalyst layer was not increased when hydrogen sulfide was added. As a result, the desulfurization rate after 100 hours was 87%, and the desulfurization rate after 8000 hours (about 1 year later) was 51%.
本発明の排ガス脱硫方法によれば、石油精製、天然ガス精製等の硫黄回収装置オフガスのように、硫化水素ガスが混入する可能性のある排ガス中の亜硫酸ガスを希硫酸として除去し、回収する際に、排煙脱硫用活性炭触媒を硫化水素ガスにより被毒させず、長期に亘り安定的に亜硫酸ガスを除去することができる。 According to the exhaust gas desulfurization method of the present invention, the sulfurous acid gas in the exhaust gas in which hydrogen sulfide gas may be mixed is removed as dilute sulfuric acid and recovered, such as off-gas of a sulfur recovery device such as petroleum refining and natural gas refining. At this time, the activated carbon catalyst for flue gas desulfurization is not poisoned by hydrogen sulfide gas, and sulfurous acid gas can be stably removed over a long period of time.
Claims (11)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004060462A JP4329573B2 (en) | 2004-03-04 | 2004-03-04 | Exhaust gas desulfurization method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004060462A JP4329573B2 (en) | 2004-03-04 | 2004-03-04 | Exhaust gas desulfurization method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2005246252A JP2005246252A (en) | 2005-09-15 |
| JP4329573B2 true JP4329573B2 (en) | 2009-09-09 |
Family
ID=35027249
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004060462A Expired - Lifetime JP4329573B2 (en) | 2004-03-04 | 2004-03-04 | Exhaust gas desulfurization method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4329573B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110127629A (en) * | 2019-04-25 | 2019-08-16 | 南京聚拓化工科技有限公司 | A kind of wet process sulfide prepares the device and technique of sulfuric acid |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5553966B2 (en) * | 2008-03-19 | 2014-07-23 | 千代田化工建設株式会社 | Mercury adsorbent and smoke treatment method using the adsorbent |
| JP5076471B2 (en) * | 2006-12-05 | 2012-11-21 | 千代田化工建設株式会社 | Method for producing carbon-based catalyst for flue gas desulfurization |
| CN102059094A (en) * | 2010-11-22 | 2011-05-18 | 山西新华化工有限责任公司 | Preparation method of sulfur-removal activated carbon containing copper |
| CN111487363B (en) * | 2020-05-07 | 2022-08-16 | 内蒙古浦瑞芬环保科技有限公司 | Method for measuring performance of desulfurization and denitrification activated carbon and application thereof |
-
2004
- 2004-03-04 JP JP2004060462A patent/JP4329573B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110127629A (en) * | 2019-04-25 | 2019-08-16 | 南京聚拓化工科技有限公司 | A kind of wet process sulfide prepares the device and technique of sulfuric acid |
| CN110127629B (en) * | 2019-04-25 | 2020-11-17 | 南京聚拓化工科技有限公司 | Device and process for preparing sulfuric acid from sulfide by wet process |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2005246252A (en) | 2005-09-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| RU2447936C1 (en) | Carbon-based catalyst for flue gas desulphurisation and method of producing said catalyst and use thereof in removing mercury from flue gases | |
| JP4831295B2 (en) | Exhaust gas desulfurization method | |
| US20070207923A1 (en) | Flue Gas Purification Process Using A Sorbent Polymer Composite Material | |
| JP6230818B2 (en) | Exhaust gas treatment apparatus and exhaust gas treatment method | |
| WO2009093574A1 (en) | System and method for treating discharge gas from coal-fired boiler | |
| KR20060112217A (en) | Exhaust gas treatment device and exhaust gas treatment method | |
| BRPI0616030A2 (en) | SO3 removal method from a flue gas stream | |
| CA2603601C (en) | Process for the removal of heavy metals from gases, and compositions therefor and therewith | |
| CN101053746B (en) | Method for ethylene glycol removing SOx (X=2 or 3) in flue gas | |
| CN101502741A (en) | Method for removing SOx from gas using polyethylene glycol | |
| JP2003138277A (en) | Mercury removal method and its system | |
| WO2004035176A1 (en) | Production of sulphur and activated carbon | |
| CN106714938A (en) | A process for the oxidation of hydrogen sulfide to sulfur trioxide with subsequent sulfur trioxide removal and a plant for carrying out the process | |
| JP4329573B2 (en) | Exhaust gas desulfurization method | |
| CN103432890A (en) | Method for removing SOx in gas by using modified polyethylene glycol | |
| CN108816018A (en) | Waste gas processing method and the method for handling the exhaust gas containing organic matter | |
| JP4326276B2 (en) | Gas purification device and flue gas desulfurization system | |
| US9764280B2 (en) | Complexation and removal of mercury from flue gas desulfurization systems | |
| CA2887440A1 (en) | Exhaust gas treatment apparatus and exhaust gas treatment method | |
| WO2005054126A1 (en) | Carbon material and flue gas treatment apparatus | |
| US20190009210A1 (en) | Enhanced injection of mercury oxidants | |
| JP2005238074A (en) | Regenerating method of active carbon catalyst for flue gas desulfurization | |
| JP2004337776A (en) | Exhaust gas treating apparatus | |
| AU2016349302B2 (en) | Method and plant design for reduction of start-up sulfur oxide emissions in sulfuric acid production | |
| JP6235705B2 (en) | Method for treating gas containing zero-valent mercury and mercury separation system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20061020 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20090226 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20090310 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20090430 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090526 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20090608 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4329573 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120626 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130626 Year of fee payment: 4 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140626 Year of fee payment: 5 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |