JP4979160B2 - Reprocessing method of desulfurization agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for treating a hydrogen sulfide removing agent consisting essentially of iron oxide into safe waste or recovering the hydrogen sulfide adsorbing function thereof after being used for removing hydro gen sulfide generated in a sewage treatment site. SOLUTION: A treating agent 8 for regenerating the hydrogen sulfide removing agent 1 consisting essentially of iron oxide by dipping or the like consists of a hydroxide of an alkali metal or alkaline earth metal and an oxidizing agent. Further, a surfactant can be added, sometimes aeration into the regenerating treating agent is carried out. At least 2 desulfurization columns 2 and 3 are mounted as a hydrogen sulfide removing apparatus. While the hydrogen sulfide removing treatment is performed in one of the desulfurization columns, the regenerating treatment can be performed in another column.

Description

尚、上記反応においては、微量のＳが生成される。
反応によって生成される硫酸ソーダＮａ２ＳＯ４は、通称湯の花などと呼称して湯浴剤などに使用される無害なものである。
【００１７】
図２はこの再生処理液８における次亜塩素酸ナトリウム濃度と再生率を示しており、使用前（バージン）の状態のものと比較すると次亜塩素酸ナトリウム濃度の差異に基づく差はほとんど無く概ね８０％程度再生されることがわかる。
図３は、脱硫化水素剤のバージンと使用済み脱硫化水素剤及びその再生処理後のＸ線回折パターンを示している。
尚、本図において、処理前はＸ線強度目盛り上４００、処理後は同８００嵩上げして表示してある。
【００１８】
以上説明してきたように、本実施の形態では、再生処理液８に脱硫化水素剤１を浸漬するから、全量均等に再生処理を行うことができる。
再生処理液８は、処理に際し有毒ガスを発生させることなく安全である。
本実施の形態では、図１において２基の脱硫塔２，３を設置したので、脱硫処理と再生処理を平行して行うことができ大変効率的であるし、再生に際し使用後の脱硫化水素剤を脱硫塔から外部に取り出すこともないからペレットの破損を防止できるし、安全作業、省力化を達成することもできるなどの利点がある。
【００１９】
次に、図４に基づいて実施の形態２を説明する。
尚、本実施の形態２において、前記実施の形態１と同様の構成部分は同一の符号を付してその具体的な説明は省略する。
本実施の形態では、脱硫塔３の下面からエアレーション１２を行い、再生反応の促進を図るようになっている。
図中１３はエア配管であり、図外の空気源から清浄な空気１４を圧送し、内部に万遍無く空気の泡を供給する。この空気は反応が最良に行われるように温度調整することもできる。
【００２０】
以上、本発明の実施の形態を説明してきたが、本発明の具体的な構成は本実施の形態に限定されるものでなく、発明の要旨を逸脱しない範囲の設計変更等があっても本発明に含まれる。
例えば、酸化剤として空気を使用しエアレーション、太陽光で酸化を行うこともできる。この場合、脱硫化水素剤をアルカリ金属またはアルカリ土類金属の水酸化物溶液に浸漬し、その状態でエアレーションを行って濾別後、人口乾燥または自然乾燥させることによって再生することもできる。
この反応は以下のようになり、有毒ガスを発生させることなく再生処理が行われる。

【００２１】
再生処理に脱硫塔を使用する場合において、再生処理液８の各成分の濃度は、脱硫塔の容積や脱硫化水素剤の量、外気温、処理時間など各種条件により、任意に設定することができる。
再生処理液８は脱硫化水素剤１を浸漬するだけで反応させるとしたが、図１の脱硫塔２、３の上部に一点鎖線で示す配管１５、１６を設け、配管９、１０で供給する再生処理液８を循環させるようにしても良い。
脱硫化水素剤１は静止状態だけでなく、流動状態で再生処理液８に接触させるようにしても良い。
脱硫塔の設置数、配管状態は任意に設定することができる。
脱硫化水素剤１はペレットの状態で再生処理を行うとしたが、半砕するなど最適な状態で再生処理することができる。
【００２２】
【発明の効果】
本発明にあたっては、硫化水素によって飽和された使用済み脱硫化水素剤から硫化水素や亜硫酸ガス等の有毒ガス発生させない安定した化合物に変成できる。
使用前の脱硫化水素剤と略同等の脱硫効果を有するように、かつ安全作業で効率的に再生することができる。
有効に再利用できるから、省資源に役立つ。
複数の脱硫塔の一方を脱硫作業に、残余を再生作業に使用することにより、脱硫作業を停止させることなく行うことができるなど効果が得られる。
【図面の簡単な説明】
【図１】本発明実施の形態１の脱硫反応と再生反応を同時に行うシステムを示す説明図である。
【図２】実施の形態１の次亜塩素酸ナトリウム濃度と再生率を示すグラフである。
【図３】実施の形態１の脱硫化水素剤の使用前、処理前、処理後のＸ線回折パターンを示すグラフである。
【図４】実施の形態２のエアレーションを行う脱硫化水素装置としての脱硫塔を示す説明図である。
【符号の説明】
１ 脱硫化水素剤
２、３ 脱硫塔
４ 排ガス
５、６ 排ガスを導入する配管
７ 切替弁
８ 再生処理液
９、１０ 再生処理液を導入する配管
１２ エアレーション
１３ エア配管
１５、１６ 再生処理液を戻す配管[0001]
BACKGROUND OF THE INVENTION
The present invention is safe after using a desulfurization agent mainly composed of iron oxide used to remove hydrogen sulfide generated in sewage treatment plants, human waste treatment plants, food industry wastewater treatment plants, landfill disposal sites, and the like. The present invention relates to a regeneration treatment agent that treats waste or restores its hydrogen sulfide adsorption function, a regeneration treatment method that uses the regeneration treatment agent, and a regeneration treatment apparatus that uses the regeneration treatment method.
[0002]
[Prior art]
Conventionally, in sewage treatment plants etc., toxic hydrogen sulfide is generated during the treatment process. Therefore, a treatment filled with a pellet-shaped desulfurization agent mainly composed of iron oxide or iron hydroxide is provided. Hydrogen sulfide is removed by passing the gas through the inside of the dehydrosulfurizing agent in the treatment tower.
In this method, since the desulfurization agent in the tower gradually deteriorates, it is replaced with a new desulfurization agent approximately every six months to one year.
By the way, the main component of this used dehydrosulfurizing agent is iron sulfide, which is extremely reactive, and when left in the air, it reacts violently with oxygen in the air and burns, thereby producing sulfurous acid gas. appear.
For this reason, conventionally, after adding water to the spent desulfurization agent saturated with hydrogen sulfide, the waste is buried in a treatment place or the like in a wet state as industrial waste.
[0003]
[Problems to be solved by the invention]
However, since the main component of the used dehydrosulfurizing agent disposed of in landfill is iron sulfide, hydrogen sulfide or sulfurous acid gas is generated over a long period of time, resulting in a new disaster at the landfill site. There is a risk of doing.
Further, since the desulfurized agent after use is disposed of in the landfill as described above, newly produced desulfurized agent is consumed one after another, which is not preferable from the viewpoint of resource protection.
[0004]
The present invention has been made to solve the above-described problems in conventional processing, and generates toxic gases such as hydrogen sulfide and sulfite gas from a spent desulfurization agent saturated with hydrogen sulfide. It is an object of the present invention to provide a recycling method useful for resource saving, which can be converted into a stable compound that is not allowed to be used, and can be reused with a desulfurization effect equivalent to that of a dehydrosulfurizing agent before use.
Since the used dehydrosulfurizing agent is iron sulfide as described above, the present inventors use various oxidizing agents including hydrogen peroxide as means for converting this into iron oxide or iron hydroxide. As a result of earnest research, it was found that it can be converted to iron oxide or iron hydroxide without generating toxic gas by treating with sodium hypochlorite or a liquid sharing alkali with hydrogen peroxide.
[0005]
[Means for Solving the Problems]
In the method for regenerating a hydrodesulfurizing agent according to claim 1 of the present invention, an oxidizing agent selected from alkali metal or alkaline earth metal hydroxide, carbonate and aqueous ammonia, sodium hypochlorite or hydrogen peroxide. A desulfurization agent regeneration treatment method comprising contacting a regeneration treatment agent comprising a desulfurization agent with at least two desulfurization devices filled with a pellet-shaped desulfurization agent mainly composed of iron oxide. In the meantime, while the desulfurization treatment is being performed, the remaining apparatus is a method of regenerating the desulfurization agent, and the regeneration process is performed by introducing the regeneration treatment agent into the desulfurization apparatus. The way to do it.
[0006]
According to a second aspect of the present invention, there is provided a regeneration treatment method for a desulfurization agent according to claim 1, wherein when the regeneration treatment for the desulfurization agent is performed in a desulfurization apparatus, Aerate inside.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 of the present invention will be described below.
FIG. 1 shows a system for simultaneously performing a desulfurization reaction and a regeneration reaction according to this embodiment.
The hydrodesulfurizing agent 1 is formed in a pellet form with iron oxide as a main component. In the present embodiment, as shown in FIG. 1, the dehydrosulfurizing agent 1 is divided into two desulfurization towers 2, 3 is filled.
The desulfurization towers 2 and 3 introduce the exhaust gas 4 containing hydrogen sulfide in the process of the sewage treatment tower into the pipes 5 and 6, and the pipes 5 and 6 are only one of the switching valves 7. Distribution is possible. That is, only one of the desulfurization towers 2 and 3 is formed so as to perform a desulfurization action and the other is in a dormant state.
In addition, the desulfurization towers 2 and 3 are provided with pipes 9 and 10 for introducing the regeneration treatment liquid 8 of the desulfurized hydrogen agent 1, and only the one where the exhaust gas 4 is not introduced by the control is regenerated. The liquid 8 is introduced.
In this figure, the exhaust gas 4 is introduced into the desulfurization tower 2 from the pipe 5, and the exhaust gas 4 passes through a number of dehydrosulfurizing agents 1, so that hydrogen sulfide is adsorbed and then discharged as a treated gas from the exhaust pipe 11. At the same time, the desulfurization tower 3 is used as a desulfurization agent regenerator, and the regenerative treatment liquid 8 is introduced from the pipe 10 until the desulfurization agent 1 is immersed, and a predetermined treatment is performed. The desulfurization agent 1 is regenerated by being kept in that state until the time elapses.
[0015]
The operation of the desulfurization tower 3 will be described. In this case, the desulfurization tower 3 is put into a resting state as described above, and the regeneration treatment liquid 8 is introduced into the desulfurization tower 3 to be used as a desulfurization agent regeneration device.
The regeneration treatment liquid 8 introduced into the desulfurization tower 3 is preferably sodium hypochlorite or a solution obtained by adding an alkali such as sodium hydroxide to hydrogen peroxide solution, and the concentration of sodium hypochlorite and hydrogen peroxide solution. It is better to add 50 ppm to 1000 ppm of an anionic surfactant or a nonionic surfactant to a solution of about 2% or more.
[0016]
The regeneration treatment liquid 8 is brought into contact with a used dehydrosulfurizing agent at room temperature or by heating, preferably at a heating temperature of 80 ° C. for 30 minutes to 3 hours, preferably for 2 hours in a stationary state or in a fluid state, and then the treatment liquid is taken out and pellets In the case of, it is evacuated or decompressed for about 30 minutes, and then artificially or naturally dried.
This reaction is as follows, and the regeneration process is performed without generating toxic gas.

In the above reaction, a trace amount of S is generated.
Sodium sulfate Na2SO4 produced by the reaction is called harmless hot water blossom or the like, and is harmless for use in hot water baths.
[0017]
FIG. 2 shows the sodium hypochlorite concentration and the regeneration rate in the regeneration treatment solution 8, and there is almost no difference based on the difference in the sodium hypochlorite concentration compared with the state before use (virgin). It can be seen that about 80% is reproduced.
FIG. 3 shows the virgin desulfurization agent, the used dehydrosulfurization agent, and the X-ray diffraction pattern after the regeneration treatment.
In this figure, the X-ray intensity scale 400 is displayed before the processing, and 800 is increased after the processing.
[0018]
As described above, in the present embodiment, since the desulfurization agent 1 is immersed in the regeneration treatment liquid 8, the regeneration treatment can be performed uniformly in the entire amount.
The regeneration processing liquid 8 is safe without generating toxic gas during processing.
In the present embodiment, since two desulfurization towers 2 and 3 are installed in FIG. 1, desulfurization treatment and regeneration treatment can be performed in parallel, which is very efficient. Since the agent is not taken out from the desulfurization tower, the pellets can be prevented from being damaged, and safety work and labor saving can be achieved.
[0019]
Next, Embodiment 2 will be described with reference to FIG.
In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the detailed description thereof is omitted.
In the present embodiment, aeration 12 is performed from the lower surface of the desulfurization tower 3 to promote the regeneration reaction.
In the figure, reference numeral 13 denotes an air pipe, which cleanly feeds clean air 14 from an air source outside the figure, and uniformly supplies air bubbles inside. The temperature of the air can also be adjusted so that the reaction takes place optimally.
[0020]
Although the embodiment of the present invention has been described above, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the invention, Included in the invention.
For example, air can be used as an oxidizing agent, and oxidation can be performed by aeration or sunlight. In this case, it can be regenerated by immersing the desulfurizing agent in a hydroxide solution of an alkali metal or alkaline earth metal, performing aeration in that state, filtering, and then artificially drying or naturally drying.
This reaction is as follows, and the regeneration process is performed without generating toxic gas.

[0021]
When a desulfurization tower is used for the regeneration treatment, the concentration of each component of the regeneration treatment liquid 8 can be arbitrarily set according to various conditions such as the volume of the desulfurization tower, the amount of the desulfurization agent, the outside air temperature, and the treatment time. it can.
The regeneration treatment liquid 8 is allowed to react by simply immersing the hydrodesulfurization agent 1. However, pipes 15 and 16 indicated by alternate long and short dash lines are provided on the upper parts of the desulfurization towers 2 and 3 in FIG. The regeneration processing solution 8 may be circulated.
The hydrodesulfurizing agent 1 may be brought into contact with the regeneration treatment liquid 8 not only in a stationary state but also in a fluid state.
The number of installed desulfurization towers and the piping state can be arbitrarily set.
The dehydrosulfurizing agent 1 is regenerated in the form of pellets, but can be regenerated in an optimal state such as half-crushed.
[0022]
【Effect of the invention】
In the present invention, a spent desulfurization agent saturated with hydrogen sulfide can be transformed into a stable compound that does not generate toxic gases such as hydrogen sulfide and sulfurous acid gas.
It can be efficiently regenerated in a safe operation so as to have a desulfurization effect substantially equivalent to that of the dehydrosulfurizing agent before use.
Since it can be reused effectively, it helps save resources.
By using one of the plurality of desulfurization towers for the desulfurization operation and the remainder for the regeneration operation, an effect can be obtained such that the desulfurization operation can be performed without stopping.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a system for simultaneously performing a desulfurization reaction and a regeneration reaction according to Embodiment 1 of the present invention.
FIG. 2 is a graph showing the sodium hypochlorite concentration and the regeneration rate in the first embodiment.
FIG. 3 is a graph showing X-ray diffraction patterns before, before and after use of the desulfurizing agent of Embodiment 1.
4 is an explanatory view showing a desulfurization tower as a desulfurization hydrogen apparatus for performing aeration according to Embodiment 2. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Dehydrosulfurization agent 2, 3 Desulfurization tower 4 Exhaust gas 5, 6 Pipe | tube 7 which introduce | transduces exhaust gas Switching valve 8 Regeneration processing liquid 9, 10 Piping which introduce | generates regeneration processing liquid 12 Aeration 13 Air piping 15, 16 Return the regeneration processing liquid Piping

Claims (2)

Desulfurized hydrogen in which a regeneration treatment agent comprising an alkali metal or alkaline earth metal hydroxide, carbonate and aqueous ammonia and an oxidizing agent selected from sodium hypochlorite or hydrogen peroxide is brought into contact with the desulfurizing agent. A method for regenerating the agent,
Install at least two desulfurization devices filled with pellet-shaped desulfurization agent mainly composed of iron oxide,
On the other hand, while the desulfurization treatment is being performed, the remaining apparatus is a method for regenerating the desulfurization agent,
A regeneration treatment method for a desulfurization agent, wherein the regeneration treatment is performed by introducing a regeneration treatment agent into a desulfurization apparatus.   The method for regenerating a dehydrosulfurizing agent according to claim 1, wherein when the regeneration treatment for the dehydrosulfurizing agent is performed in the dehydrosulfurizing apparatus, aeration is performed in the regenerating treating agent.

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