• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
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    • 专利摘要:
    1517438 Removal of nitrogen oxides and sulphur dioxide MONSANTO CO 30 Sept 1976 [1 Oct 1975] 40554/76 Heading C1A Nitrogen oxides and sulphur dioxide are removed from a gaseous mixture by contacting the gaseous mixture with a solid reagent comprising calcium oxide, magnesium oxide or a mixture thereof at a temperature above 650‹C in the presence of an amount of reducing gas comprising carbon monoxide, hydrogen or a mixture thereof sufficient to reduce all of the sulphur dioxide, nitrogen oxides and any oxygen present in the mixture.
    公开号:SU858546A3
    申请号:SU762406243
    申请日:1976-09-30
    公开日:1981-08-23
    发明作者:Милс Стюарт Хенис Джай；Катрин Триподи Мари
    申请人:Монсанто Компани (Фирма)；
    IPC主号:
    专利说明:

    The invention relates to methods for removing sulfur dioxide and nitrogen oxides from flue gases.
    The closest to the proposed _ technical essence and dostigaemo- 3 mu result is a method for cleaning flue gases from sulfur oxides and nitrogen by contacting a gaseous mixture at 335-368 ° C with a solid reagent is d ^ in the presence of a reducing gas. As a solid reagent, copper-aluminum oxide is used [1].
    However, the use of alumina as a solid reagent causes the production of undesirable by-products, such as hydrogen sulfide.
    The purpose of the invention is to simplify the process and prevent the formation of by-products.
    This goal is achieved by the fact that · according to the method of removing sulfur dioxide and nitrogen oxides by them. 25 contacting with the solid reagent at elevated temperatures in the presence of a reducing gas in qual 'stve solid reagent is calcium oxide or magnesium oxide or tsp mixture at 700-1000 ° C. 3
    Sulfur dioxide and nitrogen oxides can be effectively removed from the contents of their flue gases by contacting the latter at 700-1000 ° C with a solid reagent, including calcium oxide, magnesium oxide or a mixture thereof, in the presence of a reducing agent. This is sufficient to remove a total of more than 80% of sulfur dioxide and nitrogen oxides contained in flue gases. The reducing agents may be CO, H 2, or mixtures thereof. A preferred reducing agent is a mixture comprising about 65 to 85% CO and about 15 to 35% hydrogen.
    According to the proposed method, sulfur dioxide and nitrogen oxides are converted into the corresponding sulfides of an alkaline earth metal ion of a solid reagent used in the process, and into nitrogen gas. The latter is released into the atmosphere as a harmless product, while sulfides are regenerated and converted, by steam treatment at 650 ° С and a pressure of about 2 atm, into pure hydrogen sulfide, which can be used either in pure form or converted into pure elemental sulfur or sulfuric acid of a high degree of purity using a number of well-known reactions.
    A suitable and preferred stoichiometric ratio of the reducing agent and the products to be reduced, including oxygen, are in the range of about (2.0-3.0): 1.0. Large ratios lead to the formation of hydrogen sulfide and carbon dioxide - two toxic products, although in harmless quantities.
    The complex reaction sequence can be illustrated by reactions
    7700¾
    N0 (^ 2 -.CO С Оа. 4 N a (1 /
    S0 2 + 3C0 4-Ca0 220-¾ С a S +3 С 0 2
    S 0 2 4- ЗН 2 + С a 0 s a S ЗН g 0 (2)
    PRI me R 1. The use of calcium oxide. 9.0 g (0.16 mol) of calcium oxide are placed in a fixed-bed reactor and fixed with quartz wool. A gas mixture is then introduced into the reactor containing 7.2% COch, 7.2% HgO, 2.1% 0t, 5.6% reducing gas (75% CO and 25% H), 1120 ppm nitrogen oxides and 1120 ppm sulfur dioxide 25 (residue - nitrogen) with a space velocity of 16.80 h1 The temperature is maintained at 820 C for the entire process - 32.8 h. Analysis of the gas obtained from the JQ mass spectrometric line shows an average stress of 91.4% sulfur dioxide and 91.7% nitrogen oxides.
    The concentration of the obtained products, h / min: nitrogen 510 (based on the number of 35 removed nitrogen oxides from the obtained product), hydrogen sulfide 0730, carbon sulfide 24. Distribution of sulfur products in the target solid product, ppm: sulfide 84, sulfate 0, elemental sulfur 0.
    P r and m-r 2. The use of magnesium oxide.
    They act analogously to example 1, but apply 6.4 g (0.16 mol) of magnesium oxide as a solid reagent. The gas involved in the reaction contains 1160 ppm of nitrogen oxides, the temperature is maintained at 970 ° C during the whole process. Analysis of the resulting gas stream shows the removal of 92.1% sulfur dioxide and 81.5% nitrogen oxides from the reacted gas stream. The concentration of products in the resulting gas stream, ppm: nitrogen 470 (based on the number of removed nitrogen oxides) hydrogen sulfide 100-150, carbon sulfide 18. Basics The sulfur component in the solid target product is sulfide. Other possible components — sulfite, sulfate, and elemental sulfur — are either absent or present in small amounts.
    Example 3. The use of calcined dolomite.
    Analogously to example 1, 8.9 g (O, 18 mol) of calcined dolomite (58% calcium oxide and 39% magnesium oxide) are placed in a reactor, withstanding a temperature of 895 ° C. Analysis of the resulting gas stream shows the removal of 94.4% of sulfur dioxide and 94.8% of nitrogen oxides. The concentration of products in the resulting gas stream, ppm: nitrogen 530 (based on the number of removed nitrogen oxides), hydrogen sulfide 58-140, carbon dioxide 18. In the target solid product, the main sulfur compound is sulfide. Other possible sulfur components are sulfate or elemental sulfur.
    The table shows the amount of sulfur dioxide and nitrogen oxides removed from the flue gas, depending on the temperature when using various solid reagents.
    Thus, the proposed method allows you to effectively and simply remove oxides of nitrogen and sulfur from flue gases.
    Oxide calcium Magnesium oxide Calcined Dolomite Temperature, 0 С Removal, S0 2 ,% RemovalN0 ^% temperature / s Removing so 2 ,% Removal Ν0 (χ λ % Temperature ° C Removing S0 X % DeleteN0,% ‘205 11.9 - 220 45.8 10.7 840 73.2 70.7 280 38.1 - 320 1,0 4.2 885 93.7 92.8 355 39.9 - 500 21.7 19.0 895 94.4 94.8 465 40.3 - 665 35,3 25.7 905 93.6 93.8 555 29.3 - 780 29.0 51.1 665 33,2 16.8 875 90.1 84.3 720 59.9 25.1 955 93.6 85.8 775 61.5 70.6 970 92.1 81.5 820 91.4 91.7 975 92.1 78.0
    885 88.8
    83.6
    权利要求:
    Claims (1)
    [1]
    This invention relates to methods for removing sulfur dioxide and nitrogen oxides from flue gases. The closest to the proposed technical essence and the achieved result is a method of cleaning flue gases from sulfur oxides and nitrogen by contacting the gas mixture at 335-368 ° C with a solid reagent in the presence of a reducing gas. - Copper-alumina l is used as a solid reagent. However, the use of alumina as a solid reagent causes undesirable products, such as hydrogen sulfide, to be produced. The purpose of the invention is to simplify the process and prevent the formation of by-products. This goal is achieved by the fact that according to the method of removal of sulfur dioxide and nitrogen oxides by them. contact with a solid reagent at high temperatures in the presence of a reducing gas; calcium oxide or magnesium oxide is used as a solid reagent or and the mixture at 700-1000 ° C. Sulfur dioxide and oxides of nitrogen can be effectively removed from the flue gases containing them by contacting the latter at 700-1000 ° C with a solid reagent, including calcium oxide, magnesium oxide, or a mixture of them, in the presence of a reducing agent. This is sufficient to remove a total of more than 80% of sulfur dioxide and nitrogen oxides contained in flue gases. CO, H or mixtures of them can be reducing agents. The preferred reducing agent is a mixture comprising about 65 to 85% CO and about 15 to 35% hydrogen. According to the proposed method, sulfur dioxide and nitrogen oxides are converted into the corresponding sulfides of the alkaline earth metal ion of the solid reagent used in the process and into the nitrogen gas. The latter is emitted into the atmosphere as a harmless product, while sulphides are regenerated and converted by steam treatment at 50 ° C and a pressure of about 2 atm to pure hydrogen sulfide, which can be used either in its pure form, or it can be converted to pure elemental sulfur, or high-purity sulfuric acid using a number of well-known reactions. The stoichiometric ratio of the reducing agent and the products to be reduced, including oxygen, are expedient and preferable: values are approximately (2, (} - 3.0 |: 1.0. Large ratios lead to the formation of hydrogen sulfide and carbon monoxide) toxic products, though in harmless quantities. The complex sequence of reactions can be illustrated by the reactions 77оОЬ 2 N00) 2-, С O -S5o 24C02.tNcL SO ,, 13 О 4-С а О С and S + -3 С О g 22 CaS ZN2.0 Example: use of calcium oxide, 9.0 g (0.16 mol) of calcium oxide is placed in a reactor base layer and fix it with quartz wool. A lawn mixture containing 7.2% CO2, 7.2% HgO 2.1% Oi, 5.6% reducing gas (75% CO and 25% H ), 1120 ppm of nitrogen oxides and 1120 ppm of sulfur dioxide (residue - nitrogen) with a bulk velocity of 16.80 h. The temperature is maintained at 820 s during the whole process - 32.8 h. Analysis obtained by mass spectrometry gas shows the removal of an average of 91.4% sulfur dioxide and 91.7% nitrogen oxides. Concentrations of the resulting product h / min: nitrogen 510 {based on the amount of nitrogen oxides removed from the resulting product), hydrogen sulfide OrZ carbon monoxide 24. Distribution of sulfur products in the target solid product, ppm of sulfide 84, sulfate O, elemental sulfur O Pr and m p 2, the use of magnesium oxide. Proceed analogously to example 1, 6-, 4 g (.0.16 mol) of magnesium oxide are used as a solid reagent. The reacting gas contains 1160 ppm of nitrogen oxides, the temperature is maintained at 970 ° C throughout the process. Analysis of the resulting gas stream shows the removal of 92.1% sulfur dioxide and 81.5% nitrogen oxides from the gas stream that has entered into the reaction. The concentration of products in the resulting gas stream, ppm: nitrogen 470 (based on the amount of nitrogen oxides removed) of hydrogen sulfide 100-150, carbon monoxide 18. The main sulfur component in the solid target product is sulfide. Other possible components - sulfite, sulfate and elemental sulfur are either absent or present in insignificant amounts. Example 3. Application of calcined dolomite. Analogously to example 1, 8.9 g (0.18 mol; calcined dolomite (58% calcium oxide and 39% magnesium oxide) are placed in a reactor, maintaining a temperature of 895 s. Analysis of the resulting gas stream shows the removal of 94.4% sulfur dioxide and 94.8 % nitrogen oxides. Product concentration in the resulting gas stream, ppm: nitrogen 530 (based on the amount of nitrogen oxides removed), hydrogen sulfide 58-140, carbon dioxide sulfur dioxide 18. Sulfide is the main sulfur compound in the target solid product. Other possible sulfur components sulphate or elemental sulfur is practically and absent.The table shows the amount of removed sulfur dioxide and nitrogen oxides,% of flue gases, depending on the temperature when using various solid reagents.Thus, the proposed method allows you to effectively and easily remove oxides of nitrogen and sulfur from flue gases. of the invention f. A method for removing sulfur dioxide and nitrogen oxides from gases by contacting with solid active reagent at high temperatures in the presence of a reducing gas, characterized in that, in order to simplify the process and By avoiding the formation of by-products, calcium oxide or magnesium oxide or their mixtures, in particular, will be used as a solid reagent 66, and the process will be carried out at a temperature of 700 ° C. S. sources of information taken into account in the examination 1. Ayay Sood, KItreli IR Ihd. and Eng, Chem Prod. Res. and Oevelop, 1974, v.l3, I 3, p. 180-185.
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    同族专利:
    公开号 | 公开日
    BE846772A|1977-03-30|
    DE2644244A1|1977-04-14|
    US4011299A|1977-03-08|
    CA1050733A|1979-03-20|
    GB1517438A|1978-07-12|
    FR2326222B1|1980-03-14|
    JPS5243776A|1977-04-06|
    FR2326222A1|1977-04-29|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US2090828A|1932-06-25|1937-08-24|John W Beckman|Process for purifying sulphur dioxide bearing gases|
    FR1276886A|1960-12-09|1961-11-24|Aug Klonne|Process for gas purification|
    US3454355A|1966-05-20|1969-07-08|Chevron Res|Method of removing sulfur dioxide and nitrogen oxides from gases|
    US3459494A|1966-12-14|1969-08-05|Standard Oil Co|Process for decomposition of oxides of nitrogen|
    US3717700A|1970-08-25|1973-02-20|Us Interior|Process and apparatus for burning sulfur-containing fuels|
    US3699037A|1970-10-28|1972-10-17|Chevron Res|Catalytic cracking|
    AU5567173A|1972-06-16|1974-11-14|Princeton Chemical Res Inc|Regeneration of solid sorbents regeneration of solid sorbents|
    FR2197814B1|1972-08-29|1975-01-03|Heurtey Sa|
    GB1438119A|1972-09-01|1976-06-03|Exxon Research Engineering Co|Removal of nitrogen oxides and sulphur oxides from gases|JPS5539366B2|1975-11-12|1980-10-11|
    CA1173763A|1980-08-21|1984-09-04|Roger W. Fenstermaker|Engine performance operating on field gas as enginefuel|
    US4321242A|1980-09-30|1982-03-23|United States Steel Corporation|Low sulfur content hot reducing gas production using calcium oxide desulfurization with water recycle|
    US4517165A|1981-03-03|1985-05-14|Rockwell International Corporation|Combustion method|
    GB2172277B|1985-03-13|1989-06-21|Hokkaido Electric Power|Preparation process of desulfurizing and denitrating agents|
    FR2587236B1|1985-09-13|1987-11-13|Inst Francais Du Petrole|PROCESS FOR THE REMOVAL OF SULFUR OXIDES FROM A GAS BY MEANS OF AN ABSORPTION MASS REGENERABLE BY REACTION WITH HYDROGEN SULFIDE|
    US4718361A|1986-11-21|1988-01-12|The United States Of America As Represented By The Department Of Energy|Alkali injection system with controlled CO2 /O2 ratios for combustion of coal|
    US4829036A|1988-04-21|1989-05-09|Sanitech, Inc.|Regeneration process for spent SO2 -NOX sorbents|
    JP2674428B2|1992-07-06|1997-11-12|株式会社神戸製鋼所|Catalyst for removing nitrogen oxides and method for removing nitrogen oxides|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    US05/618,729|US4011299A|1975-10-01|1975-10-01|Process for removing sulfur dioxide and nitrogen oxides from gases|
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