KR100345737B1 - Purification method of flue gas containing h2s - Google Patents

Purification method of flue gas containing h2s Download PDF

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KR100345737B1
KR100345737B1 KR1019970073578A KR19970073578A KR100345737B1 KR 100345737 B1 KR100345737 B1 KR 100345737B1 KR 1019970073578 A KR1019970073578 A KR 1019970073578A KR 19970073578 A KR19970073578 A KR 19970073578A KR 100345737 B1 KR100345737 B1 KR 100345737B1
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hydrogen sulfide
sulfur
temperature
air
gas
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KR19990053875A (en
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이덕성
정종식
송재활
이재민
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주식회사 포스코
재단법인 포항산업과학연구원
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86—Catalytic processes
    • B01D53/8603—Removing sulfur compounds
    • B01D53/8612—Hydrogen sulfide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/12—Silica and alumina
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/20—Vanadium, niobium or tantalum
    • B01J23/22—Vanadium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/207—Transition metals
    • B01D2255/20723—Vanadium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/209—Other metals
    • B01D2255/2092—Aluminium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/30—Silica

Abstract

PURPOSE: Provided is a purification method of flue gas containing large quantity of H2S without generation of NOx. CONSTITUTION: In a purification method of flue gas containing a large quantity of H2S gas, the method is characterized in that acidic gas undergoes incomplete combustion at flame reaction temperature ranging from 1000 to 1200 deg.C by controlling the amount of air inflow into oxidizing furnace; and H2S gas is further oxidized inside catalytic oxidation reactor in the presence of silica aluminum catalyst supported with vanadium at 150 to 300 deg.C by introducing a certain amount of air corresponding to equivalent ratio of H2S.

Description

고농도 황화수소 함유 가스의 처리 방법Processing method of high concentration hydrogen sulfide containing gas

본 발명은 고농도 황화수소 함유 가스의 처리 방법에 관한 것으로, 보다 상세하게는 고농도 황화수소 함유 산성 가스를 산화로에서 불완전 연소시킨 다음, 잔류 가스를 촉매 산화 반응기에서 처리하여 NOx 발생을 억제하면서 황화수소를 처리하는 방법에 관한 것이다.The present invention relates to a method for treating a high concentration of hydrogen sulfide-containing gas, and more particularly, incomplete combustion of a high concentration of hydrogen sulfide-containing acidic gas in an oxidation furnace, followed by treatment of hydrogen sulfide while treating residual gas in a catalytic oxidation reactor to suppress NOx generation. It is about a method.

제철소, 천연 가스 정제, 정유 공장 등지에서 발생하는 고농도의 황화 수소 함유가스를 산성 가스라 하며, 이들은 통상 클라우스 공정에서 유황으로 제조하여 회수하고 있다. 클라우스 공정은 산성 가스의 연소 반응과 황화 수소와 이산화황의 촉매 반응으로 이루어져 있다.High-concentration hydrogen sulfide-containing gases generated in steel mills, natural gas refineries, refineries, and the like are called acid gases, which are usually produced by sulfur in the Klaus process and recovered. The Klaus process consists of the combustion reaction of acid gases and the catalytic reaction of hydrogen sulfide and sulfur dioxide.

상기 산성 가스는 우선 산화로에서 공기와 반응하여 유황과 이산화황을 생성한다.The acidic gas first reacts with air in an oxidation furnace to produce sulfur and sulfur dioxide.

[반응식 1]Scheme 1

Figure pat00001
Figure pat00001

[반응식 2]Scheme 2

Figure pat00002
Figure pat00002

생성된 유황은 황냉각기에서 회수되고, 반응 (2)에 의해 생성된 이산화황과 미반응잔류 황화수소는 촉매 반응기에서 다음과 같이 유황을 생성한다.The produced sulfur is recovered in a sulfur cooler, and the sulfur dioxide and unreacted residual hydrogen sulfide produced by the reaction (2) produce sulfur in the catalytic reactor as follows.

[반응식 3]Scheme 3

Figure pat00003
Figure pat00003

즉, 황화수소와 이산화황의 비가 2:1이 되어야 최대 황회수율을 얻을 수 있다.That is, the ratio of hydrogen sulfide to sulfur dioxide must be 2: 1 to obtain the maximum sulfur recovery.

현재까지는 산화로에 투입하는 공기의 양을 조절하여 이 비를 맞추고 있는데, 비를 정확하게 맞추기 힘들고, 이 비를 맞출 경우 로온도가 상승하여 설비의 관리가 어려워지거나 설비의 재질을 고온에도 견디는 고가의 재질을 사용해야 하는 문제가 있다.Up to now, this ratio is adjusted by adjusting the amount of air input to the oxidation furnace, and it is difficult to accurately match the ratio, and if this ratio is met, the furnace temperature rises, making it difficult to manage the equipment or the material of the equipment to withstand high temperatures. There is a problem with using a material.

따라서 상기 로온을 낮추기 위하여 산화로에 수증기를 공급하는 방법을 주로 이용하고 있으나, 이는 상기 반응(3)에서 열역학적 평형 반응에 의해 수증기의 함량이 높아지면 정반응이 방해받아 황회수율이 떨어지며, 수증기가 공급되는 만큼 전체 유량이 늘어나 공정 전체에 압력이 증가하거나 설비가 커지는 문제가 있다.Therefore, the method of supplying water vapor to the oxidation furnace is mainly used to lower the temperature of the furnace, but when the content of water vapor is increased by the thermodynamic equilibrium reaction in the reaction (3), the reaction is hindered and the yield of sulfur is reduced, and the water vapor is supplied. As a result, the total flow rate is increased, and there is a problem that the pressure is increased or the facility is large throughout the process.

또한 로 온도가 높아짐에 따라 투입되는 공기의 양이 늘어나 NOx가 발생하므로 환경 문제를 야기시킬 수 있다.In addition, as the furnace temperature increases, the amount of air introduced increases, resulting in NOx, which may cause environmental problems.

이에 본 발명의 목적은 상기와 같은 로 온도의 상승에 따른 문제점을 해소하고자 산화로에서 황화수소와 이산화황을 저온에서 불완전 연소시킨 다음 남은 황화수소를 촉매 산화 반응기에서 처리하는 고농도 황화수소 함유 가스의 처리 방법을 제공하고자 한다.Accordingly, an object of the present invention is to provide a method for treating a high concentration of hydrogen sulfide-containing gas in which hydrogen sulfide and sulfur dioxide are incompletely combusted at low temperature in an oxidation furnace and then the remaining hydrogen sulfide is treated in a catalytic oxidation reactor in order to solve the problems caused by the rise of the furnace temperature. I would like to.

본 발명에 의하면,According to the invention,

고농도 황화수소 함유 가스를 처리하는데 있어서,In treating high concentration of hydrogen sulfide containing gas,

산성 가스를 산화로에서 투입하는 공기량을 조절하여 1000-1200℃의 불꽃 반응 온도에서 불완전 연소시켜 생성된 유황을 제거하는 단계; 및Controlling the amount of air introduced into the oxidation furnace to remove sulfur produced by incomplete combustion at a flame reaction temperature of 1000-1200 ° C .; And

미반응 황화 수소는 촉매 산화 반응기에서 산화시켜 유황을 제조하는 단계;를 포함하는 고농도 황화수소 함유 가스의 처리 방법이 제공된다.Unreacted hydrogen sulfide is oxidized in a catalytic oxidation reactor to produce sulfur. A method for treating a high concentration hydrogen sulfide containing gas is provided.

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

우선 고농도 황화수소 함유 산성 가스를 공기와 함께 불꽃산화시켜 유황을 생성한다. 로온을 가능한한 낮게 유지하는 쪽으로 공기의 양을 적게 투입하여 연소시킨다. 로온도는 1000-1200℃를 유지하는 것이 바람직하다.First, high concentration hydrogen sulfide-containing acid gas is flame-oxidized with air to produce sulfur. Combustion is carried out with less air to keep the furnace as low as possible. The furnace temperature is preferably maintained at 1000-1200 ℃.

로온이 높아지면 황회수율이 증가하는 반면, 설비의 관리가 어려워지거나 설비의 재질을 고온에 견디는 것으로 바꾸어야 하고 생성물중에 질소 산화물이 증가하여 후공정에의 영향과 대기중으로 방출시 환경 오염을 유발할 수 있다.If the furnace temperature is increased, the recovery of sulfur is increased, but the management of the equipment is difficult or the material of the equipment needs to be changed to withstand high temperature, and the nitrogen oxides in the product increase, which may affect the post process and cause environmental pollution when released into the atmosphere. .

한편 로온이 너무 낮아지면 황회수율이 떨어지고 불꽃의 안정적인 유지가 어려워질 수 있다. 따라서 산화로에 투입되는 공기의 양은 불꽃이 안정적으로 유지되는 범위에서 가능한한 적게 투입되는 것이 바람직하다.On the other hand, if the low temperature is too low, the yield of sulfur may decrease and it may be difficult to maintain a stable flame. Therefore, it is preferable that the amount of air introduced into the oxidation furnace be introduced as little as possible in a range where the flame is stably maintained.

상기 산화로에서 생성된 유황은 유황 냉각기에서 냉각하여 액체 상태로 회수되고, 미반응 공정 가스는 촉매 산화 반응기에서 산화시켜 유황을 제조한다.Sulfur produced in the oxidation furnace is cooled in a sulfur cooler and recovered in a liquid state, and unreacted process gas is oxidized in a catalytic oxidation reactor to produce sulfur.

상기 산화로에 투입된 공기의 양이 적으므로 공정 가스중의 대부분은 황화수소이고 이산화황은 극미량 존재하게 된다.Since the amount of air introduced into the oxidation furnace is small, most of the process gas is hydrogen sulfide and trace amounts of sulfur dioxide are present.

산화촉매 반응기에서는 상기 공정 가스와 공기를 혼합시켜 촉매상에서 상기 언급한 반응(1)을 일으켜 유황을 생성한다.In the oxidation catalyst reactor, the process gas and air are mixed to generate the above-mentioned reaction (1) on the catalyst to produce sulfur.

반응(1)은 비가역 반응으로 이론적으로는 완전 전환이 가능한 반응이다. 또한 온도가 낮아질수록 전환율이 높아지는 특성을 갖는다.Reaction (1) is an irreversible reaction, theoretically a complete conversion is possible. In addition, as the temperature is lowered, the conversion rate is higher.

상기 촉매 산화 반응기에서 사용되는 측매는 실리카, 알루미나, 실리카 알루미나등의 담체에 전이금속 산화물을 담지한 촉매가 반응 활성이 있으며, 바나듐을 실리카 알루미나에 담지한 촉매가 가장 활성이 우수하다.The catalyst used in the catalytic oxidation reactor is a catalyst having a transition metal oxide supported on a carrier such as silica, alumina, silica alumina, and the catalyst having vanadium on silica alumina is the most active.

상기 촉매 산화 반응기에 투입되는 산소(공기)의 양은 반응 활성과 선택도면에서 공정 가스중에 함유된 황화수소량의 당량비만큼만 있으면 충분하다.The amount of oxygen (air) introduced into the catalytic oxidation reactor is sufficient to be equal to the ratio of the amount of hydrogen sulfide contained in the process gas in terms of reaction activity and selectivity.

투입되는 산소의 양이 보다 많아지면, 부산물로 이산화황이 생성되고, 적으면 황화수소의 전환율이 떨어지게 된다.If the amount of oxygen added is higher, sulfur dioxide is produced as a by-product, and if less, the conversion rate of hydrogen sulfide decreases.

상기 촉매 산화 반응기의 반응 온도가 너무 낮아지면 활성이 떨어지고 설비 및 촉매상에 생성된 유황이 침적되는 문제가 있고, 온도가 높아지면 평형 전환율이 떨어지며 에너지 소모가 많은 문제가 있다.If the reaction temperature of the catalytic oxidation reactor is too low, there is a problem that the activity is reduced and the sulfur produced on the equipment and the catalyst is deposited, and if the temperature is high, the equilibrium conversion is lowered and energy consumption is high.

따라서 반응 온도는 150-300℃에서 가장 적절한 결과를 얻을 수 있으며, 250℃가 보다 바람직하다.Therefore, the reaction temperature can obtain the most appropriate result from 150-300 degreeC, and 250 degreeC is more preferable.

이하, 실시예를 통하여 본 발명을 구체적으로 설명한다.Hereinafter, the present invention will be described in detail through examples.

실시예 1Example 1

황화수소 70%, 수증기 30%로된 혼합 증기 300Nm3/hr과 공기 320Nm3/hr를 산화로에 도입하고 불꽃연소시켰다. 산화로의 온도 1088℃로 반응후 생성물을 분석한 결과 황화수소는 84Nm3/hr, 이산화황은 0.2Nm3/hr이었다. 생성물중 질소 산화물은 검출되지 않았다.Introducing the mixed vapor 300Nm 3 / hr air and 320Nm 3 / hr of hydrogen sulphide in 70%, 30% water vapor in the oxidation and allowed to flame combustion. The product was analyzed after the reaction at the temperature of the oxidation furnace at 1088 ° C. As a result, hydrogen sulfide was 84 Nm 3 / hr and sulfur dioxide was 0.2 Nm 3 / hr. No nitrogen oxides were detected in the product.

실시예 2Example 2

적정 로온 산정Estimation of titration low temperature

공기의 양을 계속 줄이면서 로 온도를 관찰한 것을 제외하고는 실시예 1과 동일한 방법으로 실험하였다.The experiment was carried out in the same manner as in Example 1 except that the furnace temperature was continuously observed while the amount of air was continuously reduced.

그 결과 로온이 1000℃ 이하가 되면 불꽃이 꺼지는 것을 발견하였으며, 이때 생성물을 분석한 결과 황화수소가 145Nm3/hr로서 황화수소의 전환율이 낮아 적절한 산화로의 온도는 최소 1000℃이상이어야 함을 알 수 있었다.As a result, the flame was extinguished when the furnace temperature was below 1000 ℃, and the analysis of the product showed that the hydrogen sulfide was 145Nm 3 / hr and the conversion rate of hydrogen sulfide was low, so that the temperature of an appropriate oxidation furnace should be at least 1000 ℃. .

비교예 1Comparative Example 1

클라우스 공정에 따른 비교Comparison by Klaus Process

공기를 540Nm3/hr을 도입한 것을 제외하고는 실시예 1과 동일한 방법으로 실험하였다.Experiment was carried out in the same manner as in Example 1 except that 540 Nm 3 / hr air was introduced.

산화로 온도 1420℃에서 반응후, 생성물을 분석한 결과 황화수소는 56Nm3/hr이었고, 이산화황은 28Nm3/hr이었다. 또한 생성물중 질소 산화물의 농도는 350ppm이었다. 즉 로온이 높고 질소 산화물 발생이 많음을 알 수 있다.After the reaction at an oxidation furnace temperature of 1420 ° C., the product was analyzed to find that hydrogen sulfide was 56 Nm 3 / hr and sulfur dioxide was 28 Nm 3 / hr. The concentration of nitrogen oxides in the product was 350 ppm. That is, it can be seen that the low temperature and the generation of nitrogen oxides are high.

실시예 3Example 3

실시예 1에서 연소후 생성된 공정 가스를 냉각기에서 유황을 제거한 다음 산화촉매 반응기에 도입하고 210Nm3/hr의 공기를 혼합하여 바나듐이 담지된 실리카 알루미나 촉매를 이용하여 250℃에서 반응시켰다.In Example 1, the process gas produced after combustion was removed by sulfur in a cooler, introduced into an oxidation catalyst reactor, and 210 Nm 3 / hr of air was mixed and reacted at 250 ° C. using a silica alumina catalyst loaded with vanadium.

반응 생성물을 분석한 결과, 황화수소 0.8Nm3/hr 그리고 이산화황 0.3Nm3/hr이었다.Analysis of the reaction product showed hydrogen sulfide 0.8Nm 3 / hr and sulfur dioxide 0.3Nm 3 / hr.

상기한 바에 따르면, 산화로의 온도를 낮게 유지할 수 있어 공기의 투입량을 가능한한 적게 조절할 수 있으므로, 질소 산화물을 생성하지 않고 고농도 황화수소 함유 가스를 처리할 수 있다.According to the above, since the temperature of the oxidation furnace can be kept low and the input amount of air can be adjusted as little as possible, it is possible to treat a high concentration of hydrogen sulfide-containing gas without generating nitrogen oxides.

Claims (1)

고농도 황화수소 함유 가스를 처리하는데 있어서,In treating high concentration of hydrogen sulfide containing gas, 산성 가스를 산화로에서 투입하는 공기량을 조절하여 1000-1200℃의 불꽃 반응 온도에서 불완전 연소시켜 생성된 유황을 제거하는 단계; 및Controlling the amount of air introduced into the oxidation furnace to remove sulfur produced by incomplete combustion at a flame reaction temperature of 1000-1200 ° C .; And 촉매 산화 반응기에서 바나듐이 담지된 실리카 알루미나 촉매존재하에 150-300℃온도에서 황화수소 당량비만큼 공기를 투입하여 미반응 황화 수소를 산화시켜 유황을 제조하는 단계 ;Preparing sulfur by oxidizing unreacted hydrogen sulfide by injecting air at an equivalence ratio of hydrogen sulfide at a temperature of 150-300 ° C. in the presence of a vanadium-supported silica alumina catalyst in a catalytic oxidation reactor; 를 포함하는 고농도 황화수소 함유 가스의 처리 방법Method for treating high concentration hydrogen sulfide containing gas containing
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US5292492A (en) * 1992-05-04 1994-03-08 Mobil Oil Corporation Recovering sulfur from ammonia acid gas stream

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US5292492A (en) * 1992-05-04 1994-03-08 Mobil Oil Corporation Recovering sulfur from ammonia acid gas stream

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