JP2005161116A - Hydrogen sulfide removing material, hydrogen sulfide removing method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen sulfide removing material capable of efficiently removing hydrogen sulfide from a gas or a liquid efficiently containing hydrogen sulfide and having less labor in manufacture, and a hydrogen sulfide removing method utilizing the hydrogen sulfide removing material. <P>SOLUTION: The hydrogen sulfide removing material stores the hydrogen sulfide removing agent 1a containing iron hydroxide as a main component and having the maximum size of 0.4-25 mm in a bag 1b of nonwoven fabric comprising a synthetic resin through which a gas and a liquid can be permeated. The gas containing hydrogen sulfide or the liquid containing hydrogen sulfide is introduced into a hydrogen sulfide removing device filled with the hydrogen sulfide removing material, is contacted with small pieces of the hydrogen sulfide removing agent to react iron hydroxide with hydrogen sulfide and is adsorbed. Thereby, hydrogen sulfide in the gas containing hydrogen sulfide or the liquid containing hydrogen sulfide is removed. The hydrogen sulfide removing agent having lowered hydrogen sulfide removing function after hydrogen sulfide removal is regenerated in the hydrogen sulfide removing device by feeding a regenerating agent comprising an alkaline solution and an oxidizing agent to the hydrogen sulfide removing device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a desulfurized water material for removing hydrogen sulfide from a hydrogen sulfide-containing gas or a hydrogen sulfide-containing liquid generated by fermentation in a treatment process such as a sewage treatment plant, and a desulfurization treatment method and apparatus using the same. .

  In sewage treatment plants, manure treatment plants, food industry wastewater treatment plants, landfill disposal sites, etc., gas generated by fermentation of sludge contains toxic hydrogen sulfide in addition to carbon dioxide gas. Hydrogen treatment removes hydrogen sulfide in the gas and renders it harmless.

  As a method for removing hydrogen sulfide, a method is known in which hydrogen sulfide is removed by chemical reaction and adsorption between hydrogen sulfide and iron hydroxide (see Patent Document 1).

  FIG. 5 is a schematic view showing an example in which a conventional desulfurized water material is filled in a desulfurized hydrogen apparatus. In FIG. 5, a hydrogen sulfide-containing gas is introduced into the desulfurization apparatus 2 filled with pellets 13 that are desulfurized water material, and the hydrogen sulfide in the gas reacts with the desulfurized water material 13 and is adsorbed and removed. The

  As the pellets 13 filled in the desulfurization apparatus 2, a pellet obtained by compressing a desulfurization agent such as limonite (limonite) mainly composed of iron hydroxide into a columnar shape with an organic binder is used.

Also, if the desulfurization function of the pellet deteriorates as the desulfurization treatment time elapses, the pellet is taken out from the desulfurization device, and the pellet is washed and regenerated with a regenerant comprising an alkaline solution and an oxidizing agent. Return to the dehydrosulfurizer and use repeatedly.
JP 2002-253963 A

  However, the above-described pellet-shaped desulfurized water material filled as it is has the following problems.

(1) Since the pellets are compression-molded in a columnar shape, not only is the production time consuming, but the pellet surface reacts by contact with hydrogen sulfide, but it is difficult for hydrogen sulfide to penetrate inside the pellet, so a considerable part Remains unreacted and the reaction efficiency is poor and wasteful.

(2) Since the pellets are columnar, they are not uniformly filled in the desulfurized hydrogen apparatus, so that gas passages are formed in the desulfurized hydrogen apparatus, and in particular, voids larger than the inside of the tower are formed in the wall portion. As a result, the gas does not flow uniformly and the contact with the pellets becomes non-uniform, and the ability of the dehydrosulfurizing agent is not fully utilized.

(3) Since the pellets are swollen by water generated by the reaction of hydrogen sulfide and iron hydroxide and the volume is increased, when taking out from the desulfurization apparatus and regenerating it, it takes a lot of labor and time to take out and workability Is bad.

(4) Since the pellets are manufactured by compression molding using a binder, a blackened and dirty drainage is produced by the reaction between the binder and the regenerant during regeneration.

  Therefore, the present invention provides a desulfurized water material that can be efficiently dehydrogenated from a gas or liquid containing hydrogen sulfide and that does not require time-consuming production, and a desulfurized hydrogen treatment method that uses this desulfurized water material. To do.

  The desulfurized water material of the present invention is characterized in that a hydrodesulfurizing agent mainly composed of iron hydroxide and / or iron oxide is contained in a fluid-permeable bag.

  A known dehydrosulfurizing agent containing essentially iron hydroxide, for example, limonite (limonite), which is iron hydroxide, can be used as the dehydrosulfurizing agent stored in the bag. In particular, iron sludge is used to remove scale and metal powder on the surface of steel, and to use metal sludge (hereinafter referred to as “metal sludge”) that is produced by acid washing with an alkali and neutralized with alkali. It is suitable because it is high.

  Metal sludge dehydrated with limonite, filter press, etc. is usually in the shape of a lump, so it can be crushed into granular, powdery, flaky small pieces that are easy to store in bags, compared to conventional pellets. The contact area of the gas or liquid can be increased, and since it is used as it is without compression molding, the reaction is promoted and the desulfurization efficiency can be improved. The maximum size of the small piece is preferably 0.4 to 25 mm, particularly 2 to 5 mm.

  A fluid-permeable material is used for the cloth forming the bag containing the desulfurizing agent. The bag material is made to function by bringing the hydrogen sulfide containing gas and hydrogen sulfide containing liquid into contact with each other and the hydrogen sulfide containing gas or hydrogen sulfide containing liquid is contained in the bag. The one that permeates the alkaline solution and oxidizing agent used in the above is used. In addition, during the reaction or regeneration of the hydrodesulfurizing agent, the dehydrosulfurizing agent repeatedly expands and contracts, so the surface peels off as a powder, so that the peeled powder does not flow out of the powder. Use a material that is difficult to penetrate. Moreover, since it has durability with respect to the gas or liquid to be processed, and also when an alkali and an oxidizing agent are used as the regenerant in the regeneration of the desulfurization agent, it must have durability against these.

  As the fabric satisfying the above conditions, a fabric knitted with synthetic fiber or cotton, or a nonwoven fabric made of a synthetic resin such as polypropylene or polyethylene is suitable.

  The size and thickness of the bag are appropriately determined in consideration of the capacity of the desulfurization agent, the size and filling amount of the desulfurization agent apparatus filled with the desulfurized water material, the convenience of handling, and the like.

  The desulfurized water material of the present invention is filled in a desulfurized hydrogen device, and the hydrogen sulfide-containing liquid or desulfurized hydrogen-containing gas introduced into the desulfurized hydrogen device permeates the bag, Hydrogen sulfide in the liquid or gas is removed by reaction and adsorption.

  In addition, the desulfurization agent whose desulfurization function has been reduced is applied to a desulfurization device using a rejuvenating agent that uses an antkari solution such as sodium hydroxide in combination with an oxidizing agent such as sodium hypochlorite, hydrogen peroxide, and air. By sending it in, the desulfurized hydrogen agent in the bag can be regenerated. In this case, regeneration can be performed more efficiently than adding a small amount of surfactant. Of course, it is possible to remove the desulfurization agent from the bag and regenerate it. However, it takes time and is not easy to work. Is efficient.

  According to the present invention, the bag is deformed in the desulfurization apparatus to ensure a uniform gap, so that there is no bias in the gas passage in the apparatus, the contact between the desulfurization agent and hydrogen sulfide is not uneven, The reaction part is reduced and the chemical reaction and adsorption are promoted to increase the hydrogen sulfide absorption efficiency of the desulfurization agent. As a result, the amount of desulfurization agent used can be reduced compared to the pellets, so the desulfurization device has Can be miniaturized.

  In addition, according to the present invention, since a large amount of the desulfurization agent can be charged into and taken out from the desulfurization apparatus in units of bags, workability is good. Furthermore, since no binder is used, the drainage from the regeneration process is not contaminated.

  FIG. 1 is a schematic view showing an example in which a desulfurized water material of the present invention is filled in a desulfurized hydrogen apparatus. In FIG. 1, a desulfurized hydrogen raw material 1 containing a granular dehydrosulfurizing agent 1 a obtained from metal sludge in a polypropylene nonwoven fabric bag 1 b is filled in a desulfurized hydrogen apparatus 2.

  FIG. 2 is a schematic view showing one embodiment of a desulfurization hydrogen treatment facility using the desulfurized water material of the present invention. In this embodiment, two desulfurization devices 2 and 3 are arranged, and a hydrogen sulfide-containing gas 4 discharged in the sewage treatment process is introduced into the desulfurization devices 2 and 3 through the introduction pipes 5 and 6. Is done. The hydrogen sulfide-containing gas 4 can be circulated only to one of the desulfurization devices by the switching valve 7, and the other desulfurization device is deactivated to regenerate the desulfurization agent 1a. In FIG. 2, the hydrogen sulfide-containing gas 4 is introduced into the desulfurization device 2 through the introduction pipe 5, passes through the non-woven bag 1b of the desulfurized water material 1, contacts the desulfurization agent 1a, reacts and adsorbs. The desulfurized hydrogen is removed and the treated gas rendered harmless is discharged into the atmosphere through the exhaust pipe 11.

  The hydrogen sulfide-containing gas is not introduced into the other desulfurization apparatus 3 and is in a resting state. During this period, the desulfurization agent 1a is regenerated. In this embodiment, an example of using caustic soda as an alkaline solution and sodium hypozinc acid as an oxidizing agent is used as a regenerating agent. The caustic soda 8 is introduced through the introduction / discharge pipe 9 until the liquid level reaches a level sufficient to immerse the desulfurized water material 1 in the desulfurization apparatus 3. Sodium hypozinc acid soda 10 is introduced from a pipe 12 for introduction / discharge connected to the lower part of the desulfurization apparatus 3. The regenerating agent permeates through the non-woven bag 1b and comes into contact with the dehydrosulfurizing agent 1a to regenerate. When the regeneration is completed, the treatment liquid is discharged from the introduction / discharge pipe 12 and waited for the next desulfurization operation.

  When the hydrogen sulfide concentration in the treated gas is measured and the chemical reaction of the desulfurization apparatus 2 that has been performing the desulfurization process is saturated or has reached a state close thereto, the switching valve 7 is switched to sulfidize. The hydrogen-containing gas 4 is introduced into the other desulfurized hydrogen apparatus 3 and the one dehydrosulfurized apparatus 2 is put into a resting state, during which the dehydrosulfurizing agent is regenerated.

  Thereafter, the hydrogen sulfide can be continuously removed from the hydrogen sulfide-containing gas by repeating the same operation and alternately performing the desulfurization process of the desulfurization apparatus and the regeneration process of the desulfurization agent.

  FIG. 3 is a graph showing the relationship between the desulfurized hydrogen adsorption ratio and the number of desulfurized hydrogen treatments for the desulfurized water material of the present invention, and FIG. 4 is a graph showing the relationship between the permeation amount of the treatment liquid and the number of desulfurized hydrogen treatments.

  In FIG. 3, a polypropylene non-woven fabric bag containing metal sludge was filled into a desulfurization apparatus, and desulfurization and regeneration were repeated in the apparatus. In the regeneration treatment, sodium zinc oxalate was used as an oxidizing agent up to twice, and hydrogen peroxide was used thereafter. As a result, although the adsorption amount was different due to the difference in the regeneration treatment, the desulfurization treatment could be performed stably with the desulfurized water material filled in the apparatus.

  Further, as shown in FIG. 4, in the example of regeneration using sodium hypozinc acid as the oxidizing agent, the permeation amount of the treatment liquid could be kept substantially constant even when the number of times increased.

It is a schematic diagram which shows the example which filled the desulfurized water raw material of this invention into the desulfurization hydrogen apparatus. It is the schematic which shows one Example of the desulfurization hydrogen treatment equipment using the desulfurization water raw material of this invention. It is a graph which shows the relationship between the desulfurization hydrogen adsorption ratio by the desulfurization water raw material of this invention, and the frequency | count of a desulfurization process. It is a graph which shows the relationship between the permeation | transmission amount of the desulfurization water raw material processing liquid of this invention, and the frequency | count of a desulfurization process. It is a schematic diagram which shows the example which filled the conventional desulfurization water raw material into the desulfurization hydrogen apparatus.

Explanation of symbols

1: Desulfurized water material 1a: Desulfurized hydrogen agent 1b: Non-woven fabric bag 2, 3: Desulfurized hydrogen device 4: Hydrogen sulfide-containing gas 5, 6: Pipe for introduction 7: Switch valve 8: Alkaline solution (caustic soda)
9: Pipe for introduction / discharge 10: Oxidizing agent (sodium zinc oxalate)
11: Exhaust pipe 12: Pipe for introduction / discharge 13: Pellet

Claims (4)

  A desulfurized water material characterized by containing a hydrodesulfurizing agent mainly composed of iron hydroxide and / or iron oxide in a fluid-permeable bag.   A desulfurized hydrogen apparatus comprising the desulfurized water material according to claim 1 filled in the apparatus.   A desulfurization treatment method comprising removing hydrogen sulfide from a hydrogen sulfide-containing fluid by feeding the hydrogen sulfide-containing fluid into the desulfurization apparatus according to claim 2.   The desulfurized water material whose desulfurized hydrogen function is reduced by the desulfurized hydrogen treatment method according to claim 3 is regenerated in the desulfurized hydrogen apparatus by feeding a regenerant into the desulfurized hydrogen apparatus. Desulfurization treatment method.

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