KR20210097391A - Apparatus for Eliminating Harmful Gas Containing Hydrogen Sulfide - Google Patents

Abstract

The present invention relates to a harmful gas containing hydrogen sulfide removal device, which effectively removes harmful gases including hydrogen sulfide discharged from a sewage treatment plant, a manure treatment plant, a food waste treatment plant, a wastewater treatment plant, or various industrial facilities, and efficiently separates and recovers separated sulfur. More specifically, the harmful gas containing hydrogen sulfide removal device comprises: a liquid catalyst tank containing a predetermined liquid catalyst; a reaction tower in which a spraying means-filler layer having one spray nozzle with one spray hole is installed on an upper part of the liquid catalyst tank and a gas supply port through which exhaust gas is introduced from the facility and a gas discharge port through which the treated gas is discharged are installed; and a circulation means transferring the liquid catalyst to the spray means through a suction port in the liquid catalyst tank.

Description

Harmful gas removal device containing hydrogen sulfide {Apparatus for Eliminating Harmful Gas Containing Hydrogen Sulfide}

The present invention relates to a harmful gas removal device containing hydrogen sulfide, and more particularly, effectively removes harmful gas containing hydrogen sulfide discharged from facilities such as a sewage treatment plant, a manure treatment plant, a food waste treatment plant, a wastewater treatment plant, or various industrial facilities, It relates to a harmful gas removal device containing hydrogen sulfide for efficiently separating and recovering liberated sulfur.

A process of producing biogas by digesting methane gas and food waste generated from a sewage treatment plant, excrement treatment plant, food waste treatment plant, sewage treatment plant, or various industrial facilities (especially, in a digester of a facility that reduces sewage sludge generated during the sewage treatment process) , hydrogen sulfide (H2S), mercaptan (R-SH), phenol (R-OH), methyl ethyl ketone, formaldehyde (HCHO), ammonia (NH3), Noxious gas containing hydrogen sulfide such as amine (R-NH2) is generated. These harmful gases containing hydrogen sulfide cause odor, and when exposed to the human body for a long time, cause olfactory and visual disturbances and nerve abnormalities, and cause corrosion of pipes and equipment. is strictly regulated.

In general, dry and wet processes are widely known as representative methods for treating and detoxifying harmful gases containing hydrogen sulfide. In addition, since it cannot remove harmful gases other than sulfur compounds, there is a disadvantage that a separate device for removing other harmful gases must be added.

Accordingly, a liquid-phase catalytic oxidation method has been proposed as a method to overcome the disadvantages of the conventional wet process method using caustic soda. This method oxidizes a sulfur compound-based gas to solid sulfur using the solubility and redox reaction of the gas at room temperature and pressure. It is to remove and convert hydrocarbon-based, ammonia, and amine-based gases into harmless carbon dioxide and nitrogen. Since the catalyst used at this time is rapidly regenerated by oxygen, there is no need to supply additional chemicals (catalysts) other than the replenishment level, and there are advantages in that wastewater and secondary pollutants are not generated.

The present inventor developed and improved an apparatus for applying the liquid-phase catalytic oxidation method (Utility Model Registration Application No. 20-2000-0001391), and has been registered as registered patents 10-1223159 and 10-1462054 (FIGS. 1a, 1b) reference).

These are basically a liquid catalyst tank 10 containing a predetermined liquid catalyst, a reaction tower 20 in which a spray means 21 - a filler layer 22 is installed on the upper portion of the liquid catalyst tank 10, and the liquid catalyst The circulation means 30 for transferring the liquid catalyst to the spray means 21 through the inlet 31 in the tank 10, respectively, is formed on one side of the reaction tower 20, and harmful gas containing hydrogen sulfide is introduced and It is a harmful gas removal device containing hydrogen sulfide including a gas supply port 23 and a gas discharge port 24 to be discharged. Among them, registered patent 10-1223159 (refer to FIG. 1a) enables the automatic removal of free sulfur deposited in the catalyst tank to ensure worker safety and continuity of device operation, and registered patent 10-1462054 ( 1b) shows that the cost and maintenance cost are significantly reduced compared to the prior art by simplifying the structure of the liquid catalyst tank.

However, these prior technologies made it possible to effectively remove harmful gases including hydrogen sulfide emitted from facilities such as various industrial facilities and to efficiently separate and recover liberated sulfur. A problem was found. ① The gas discharged from various facilities contains a considerable amount of dust, which is collected and accumulated in the liquid catalyst. The dust accumulated in the liquid catalyst not only clogs some of the plurality of spray nozzles corresponding to the spray means or a part of the filler layer, but also contaminates the recovered glass sulfur, making recycling difficult. ② The reaction tower is usually equipped with an inspection window to observe the inside (see Fig. 1c), but it is difficult to check whether the spray nozzle or the filler layer inside is blocked through the inspection window. ③ Contrary to the theory, ammonia in the gas discharged from the facility is not sufficiently removed by the liquid catalyst, so the ammonia odor remains in the finally discharged gas.

① ② above cause drift and dead space, eventually reducing the efficiency of the removal device (at this time, it is difficult to detect the blockage that causes the decrease in efficiency), and periodic cleaning and regeneration of the spray nozzle or filler layer is required. and ③ causes surrounding air pollution and civil complaints.

Utility model registration application No. 20-2000-0001391 Registered Patent 10-1223159 Registered Patent 10-1462054

The present invention prevents the spraying means or the filler layer from clogging even if there is dust contained in the gas discharged from various facilities, and when it is clogged, it can be checked immediately. intended to provide.

Another object of the present invention is to provide a harmful gas removal device containing hydrogen sulfide capable of removing dust or dust and ammonia contained in the gas discharged from the facility.

The present invention for achieving the above object,

a liquid catalyst tank containing a predetermined liquid catalyst; A reaction tower in which a spraying means-filler layer is installed on the upper portion of the liquid catalyst tank and having one spray nozzle with one spray hole, a gas supply port through which exhaust gas is introduced from the facility and a gas outlet through which the treated gas is discharged; and It is characterized in that it is a harmful gas removal device containing hydrogen sulfide including a circulation means for transferring the liquid catalyst to the spraying means through the suction port in the liquid catalyst tank.

As described above, according to the present invention, since the liquid catalyst is sprayed by one large-size injection nozzle, the blocking of the injection nozzle is prevented even if the exhaust gas of various facilities contains dust, and even if it is blocked, it can be immediately detected and corrected. be able to Accordingly, the structure of the reaction tower is simplified as well as easy to manage, so that the cost and maintenance cost can be significantly reduced compared to the conventional apparatus.

In addition, according to the present invention, by removing dust or dust and ammonia contained in the gas discharged from the facility in advance, the removal device by the liquid-phase catalytic oxidation method is not blocked, and high-purity free sulfur that is not contaminated can be recovered and recycled. do. Prevention of blockage or immediate detection and correction of blockage enables efficient operation of the device, and high-purity free sulfur is an ancillary revenue, which in turn has the effect of reducing the operating cost of the device.

1A and 1B are conceptual cross-sectional views of an example of a harmful gas removal device including hydrogen sulfide to which a liquid catalyst method according to the prior art is applied.
Figure 1c is a photograph showing an example of the inspection window formed in the reaction tower in the removal device according to the present invention.
Figure 2 is a conceptual diagram of a harmful gas removal device according to the present invention.
Figure 3a is a conceptual diagram of a spraying means consisting of a plurality of spray nozzles according to the prior art.
Figure 3b is an example of various injection nozzles applied to the pre-experiment for the present invention.
Figure 3c is an example of an injection nozzle confirmed to be suitable as a spray means of the harmful gas removal device according to the present invention.
Figures 4a and 4b are a conceptual diagram and an installation example photograph of a harmful gas removal device according to the present invention in which a washing unit is installed, respectively.
5 is a conceptual view showing an example in which an oxidation tank is additionally installed in the harmful gas removal device according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. However, the accompanying drawings are only examples for easily explaining the content and scope of the technical idea of the present invention, and thereby the technical scope of the present invention is not limited or changed. It will be natural for those skilled in the art that various modifications and changes can be made within the scope of the technical spirit of the present invention based on these examples.

In the present invention, hydrogen sulfide, mercaptans, amines, and other irritating gaseous substances (hereinafter referred to as 'noxious gas containing hydrogen sulfide') are dissolved in a liquid phase (liquid catalyst) containing a catalyst to form an oxidation/reduction reaction of the catalyst. It relates to a harmful gas removal device containing hydrogen sulfide to which a method of removing harmful gas components is applied.

According to the present invention, a liquid catalyst tank 10 containing a predetermined liquid catalyst (LC), a spraying means 21 having a single injection nozzle on the upper portion of the liquid catalyst tank 10-filler layer 22 ) is installed, the reaction tower 20 having a gas supply port 23 through which exhaust gas is introduced from the facility and a gas outlet 24 through which the treated gas is discharged, and a suction port 31 in the liquid catalyst tank 10. It relates to a harmful gas removal device containing hydrogen sulfide including a circulation means (30) for transferring the liquid catalyst to the spray means (21) through the. A conceptual diagram of a removal device according to the present invention is shown in FIG. 2 . Although the illustration of the circulation means 30 is omitted in FIG. 2, the circulation means 30 may refer to those shown in FIGS. 1A, 1B or 5 .

The liquid catalyst tank 10 is a container in which the liquid catalyst circulates in the harmful gas removal device containing hydrogen sulfide.

The reaction tower 20 is a space in which the falling liquid catalyst and the exhaust gas flowing in and passing through the gas supply port 23 contact and react. In the reaction tower 20, the atomizing means 21-filler layer 22 is installed in one or multiple stages, or a one-layer spraying means 21 and a plurality of filler layers 22 are installed. .

The spray means 21 functions to spray the liquid catalyst sent by the circulation means 30 to the filler layer 22 . According to the prior art, as shown in Figures 1a, 1b and 3a, the spraying means 21 was composed of a plurality of spray nozzles. For example, in the case of an inflow gas volume of 200 m 3 /min and a diameter of 2 m of the reaction tower 20, 32 injection nozzles for spraying at 18.5 liter/min were installed and operated. However, when a large number of spray nozzles are applied As described above, it causes problems such as difficulty in checking for occlusion and occlusion due to dust, and increase in pressure and load in the facility due to occlusion.

Accordingly, the inventors of the present invention performed a pre-experiment targeting pipe-type, perforated and single-spherical injection nozzles of various sizes and shapes as shown in FIG. 3B . As a result, applying one single hole and one spherical injection nozzle shown at the bottom of FIG. 3B as the spraying means 21 so that the liquid catalyst is sprayed on the upper entire surface of the filler layer 22 not only minimizes clogging, but also minimizes clogging. It was confirmed that an immediate response was possible. In particular, the so-called full corn type spiral nozzle shown in FIG. 3c exhibits characteristics such as a large spray area, even spraying, minimal blockage, and immediate confirmation when blockage is applied to the removal device according to the present invention. was most appropriate for

In the present invention, the filler layer 22 is filled with a large specific surface area, for example, a pall ring or tellertte filler, so that the sprayed liquid catalyst efficiently comes into contact with the rising exhaust gas while flowing down the surface of the filler. In the prior art, a filler of a single standard was used. As described above, partial blockage occurs depending on the area, thereby continuously reducing the efficiency of the removal device, and frequent (2 to 3 times/year) cleaning or replacement of the filler is required. there was Accordingly, the present inventors have found that, as a result of various preliminary experiments, when a filler of a larger size is stacked on the filler layer, the occlusion is significantly reduced under the same conditions, so that it is cleaned in the normal device inspection/repair process performed every 1 to 2 years. It was enough. Since the filler layer is not agitated, fillers of different sizes are not mixed as a whole and remain in a layered manner. Since the size of the filler is too subdivided and stacked is rather difficult to fill and wash/regeneration of the filler, it is preferable to use 2-3 kinds of filler. In an example of the removal device according to the present invention, the filler layer 22 was configured using the filler having the shape and standard shown in the following table, but is not limited thereto. In FIG. 2 , it is conceptually illustrated that three types of fillers having different sizes are applied.

In the present invention, the circulation means 30 transfers the liquid catalyst in the liquid catalyst tank 10 to the spray means 21 so that the liquid catalyst continues to circulate.

On the other hand, as described above, the gas discharged from various facilities contains a considerable amount of dust or ammonia. The dust is collected in the liquid catalyst and accumulated while circulating together. The accumulated dust is deposited on the liquid catalyst transfer pipe, the circulation pump 32, the spray means 21, the filler layer 22, etc. to inhibit the operation of the removal device and shorten the life. In addition to shortening, it contaminates the separated free sulfur, reducing its recycling value. In addition, the ammonia contained in the gas is not sufficiently removed by the liquid catalyst, contrary to the theory, so there is a problem that the ammonia gas is included in the final discharged gas.

It is preferable to additionally install a washing unit 40 for removing dust or dust and ammonia contained in the gas introduced therein at the front end of the gas supply port 23 of the removal device according to the present invention.

In the present invention, the washing unit 40 may adopt various structures and shapes capable of adsorbing and removing dust or ammonia in gas. However, for the convenience of manufacturing and maintenance of the entire removal device, it is preferable that the configuration of the washing unit 40 be the same as that of the 'removal device' except that water is used instead of the liquid catalyst.

That is, in the present invention, the washing unit 40 includes a water tank 41; A single or multi-stage spraying means (42a)-filler layer (42b) is installed on the upper portion of the water tank, and the gas inlet (42c) through which the exhaust gas flows from the facility and the gas supply port (23) of the removal device a reaction tower 42 having a gas outlet 42d connected thereto; and a circulation means (43) for transferring water to the spray means (42a) through an inlet in the water tank (41). The functions and characteristics of each component of the washing unit 40 may be the same as those of the component of the removal device corresponding thereto, and thus a detailed description thereof will be omitted.

A simplified conceptual diagram and an installation example (a 250cm diameter removal device installed in a public sewage terminal treatment plant in Uijeongbu City) of the removal device according to the present invention including the washing unit 40 are attached to FIGS. 4a and 4b, respectively.

On the other hand, in the present invention, it is preferable to further provide an oxidation tank 51 for accelerating the oxidation (regeneration) of the liquid catalyst so as to further increase the removal efficiency of the harmful gas containing hydrogen sulfide (see FIG. 5). At this time, the oxidation tank 51 is connected to the liquid catalyst tank 10 to circulate the liquid catalyst, and a predetermined oxygen (air) supply means (not shown) supplies sufficient oxygen to the liquid catalyst remaining in the oxidation tank 51 . By doing so, the oxidation (regeneration) of the liquid catalyst is faster. The liquid catalyst regenerated in this way may be returned to the liquid catalyst tank 10 or may be directly transferred to the spraying means 21 through the circulation means 30 . This perfectly oxidized (regenerated) liquid catalyst rapidly oxidizes harmful gas components including hydrogen sulfide in the contacting gas to convert it into harmless and odorless free sulfur, carbon dioxide, water, nitrogen, etc. The oxidation tank 51 is applied in the form of a bioreactor in which the iron oxidizing bacterium Thiobacillus ferrooxidans is immobilized and oxygen (air) is supplied so that the oxidation (regeneration) of the liquid catalyst in the oxidation tank 51 can be made faster and more effectively. It will also be possible Since the bioreactor in which bacteria are immobilized is well known in the art, a detailed description thereof will be omitted.

LC. liquid catalyst
10. Liquid catalyst tank
20. Reaction Tower
21. Spray means 22. Filler layer
23. Gas inlet 24. Gas outlet
30. Circulation means
31. Inlet 32. Circulation Pump
40. Flush unit
41. Water tank 42. Reaction tower 42a. spraying means
42b. Filler layer 42c. gas inlet 42d. gas outlet
43. Circulation means
51. Oxidation tank

Claims (8)

a liquid catalyst tank containing a predetermined liquid catalyst;
a reaction tower in which a spraying means-filler layer is installed on the upper portion of the liquid catalyst tank and has one spray nozzle, and a gas supply port through which exhaust gas is introduced from the facility and a gas outlet through which the treated gas is discharged; and
Circulation means for transferring the liquid catalyst to the spray means through the suction port in the liquid catalyst tank;
According to claim 1,
In the filler layer,
Noxious gas removal device containing hydrogen sulfide, characterized in that the filling material of a larger standard is stacked as it goes down.
3. The method of claim 2,
In the filler layer,
Noxious gas removal device containing hydrogen sulfide, characterized in that the filler of small-medium-large size is stacked from above.
4. The method according to any one of claims 1 to 3,
at the front end of the gas supply port
Noxious gas removal device containing hydrogen sulfide, characterized in that a washing unit for removing dust or dust and ammonia contained in the inflow gas is additionally installed.
5. The method of claim 4,
The washing unit is
water tank ;
a reaction tower in which a spray means-filler layer is installed on the upper portion of the water tank, a gas inlet through which exhaust gas is introduced from the facility, and a gas outlet connected to the gas supply port of the removal device; and
and a circulation means for transferring water to the spray means through an inlet in the water tank.
6. The method of claim 5,
The spray means is a harmful gas removal device containing hydrogen sulfide, characterized in that it has one injection nozzle.
6. The method of claim 5,
In the filler layer,
Noxious gas removal device containing hydrogen sulfide, characterized in that the filler of small-medium-large size is stacked from above.
4. The method according to any one of claims 1 to 3,
Noxious gas removal apparatus comprising hydrogen sulfide, characterized in that it further comprises an oxidation tank connected to the liquid catalyst tank to circulate the liquid catalyst, and to promote oxidation of the liquid catalyst by supplying oxygen.

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