REUSABLE POLYMERIC MATERIAL FOR REMOVING SILOXANE COMPOUNDS IN BIOGAS, METHOD THEREBY AND APPARATUS THEREFOR

Abstract

Provided are a reusable polymeric material for removing siloxane compounds in biogas, a method for removing siloxane using the same, and an apparatus therefor, and more particularly, a polyacrylate-based polymer absorbent for removing siloxane compounds in biogas and a method for removing siloxane compounds in biogas. The method for removing siloxane compounds in biogas includes (a) providing the biogas, and b) absorbing the siloxane compounds in a polymer absorbent by passing the biogas through the polymer absorbent according to any one of claims 1 to 5.

Claims

1. A polyacrylate-based polymer absorbent for removing siloxane compounds in biogas.

2. The polymer absorbent of claim 1, wherein the polymer absorbent is repetitively used through a desorption reproduction process of the siloxane compounds.

3. The polymer absorbent of claim 1, wherein the polymer absorbent is prepared through ion exchange of sodium polyacrylate.

4. The polymer absorbent of claim 1, wherein the polymer absorbent is coated or supported on a porous material.

5. The polymer absorbent of claim 1, wherein when the siloxane concentration of the biogas is equal to or less than 200 ppm, a siloxane removal rate is equal to or greater than 99%.

6. A method for removing siloxane compounds in biogas, the method comprising the steps of: (a) providing the biogas; and (b) absorbing the siloxane compounds in a polymer absorbent by passing the biogas through the polymer absorbent according to claim 5.

7. The method for removing siloxane compounds in biogas of claim 6, wherein the absorbing step (b) includes absorbing the siloxane compounds in the polymer absorbent in a temperature range of 15 to 30° C.

8. The method for removing siloxane compounds in biogas of claim 6, further comprising: desorbing for reproducing the polymer absorbent of claim 5 in a temperature range of 60 to 100° C. after the step (b) or in parallel with the step (b).

9. An apparatus for removing siloxane compounds in biogas, the apparatus comprising: (i) a biogas providing unit; and (ii) one or more absorbing units including a polymer absorbent according to claim 5.

10. The apparatus for removing siloxane compounds in biogas of claim 9, wherein the absorbing units operate in an absorbing step in a temperature range of 15 to 30° C.

11. The apparatus for removing siloxane compounds in biogas of claim 9, wherein the absorbing units are constituted by two or more absorbing units.

12. The apparatus for removing siloxane compounds in biogas of claim 11, wherein at least one of the absorbing units operates in a step of desorbing the siloxane compounds absorbed in a temperature range of 60 to 100° C. in order to reproduce the polymer absorbent.

13. The apparatus for removing siloxane compounds in biogas of claim 12, wherein the absorbing unit operating in the desorbing step operates by using waste heat of an engine operating by biogas from which the siloxane compounds are removed.

14. The apparatus for removing siloxane compounds in biogas of claim 9, the apparatus further comprising: one or more units selected from a water removing unit, a sulfur compound removing unit, a nitride oxide removing unit, a pressing unit, a decompressing unit, and a particle filter unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0032] FIG. 1 is a schematic diagram illustrating a technique for removing siloxane in biogas;

[0033] FIG. 2 is a graph illustrating a siloxane concentration and a total absorption amount over time; and

[0034] FIG. 3 is a graph illustrating desorption performance comparison of siloxane over time.

DETAILED DESCRIPTION OF THE EMBODIMENT

[0035] Advantages and features of the present disclosure, and methods for accomplishing the same will be more clearly understood from exemplary embodiments described below with reference to the accompanying drawings. However, the present disclosure is not limited to the following exemplary embodiments but maybe implemented in various different forms. The exemplary embodiments are provided only to complete disclosure of the present disclosure and to fully provide a person having ordinary skill in the art to which the present disclosure pertains with the category of the disclosure, and the present disclosure will be defined by the appended claims.

[0036] The shapes, sizes, ratios, angles, numbers, and the like illustrated in the accompanying drawings for describing the exemplary embodiments of the present disclosure are merely examples, and the present disclosure is not limited thereto. Like reference numerals generally denote like elements throughout the present specification. Further, in the following description, a detailed explanation of known related technologies may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure. The terms such as “including,” “having,” and “consist of” used herein are generally intended to allow other components to be added unless the terms are used with the term “only”. Any references to singular may include plural unless expressly stated otherwise.

[0037] Components are interpreted to include an ordinary error range even if not expressly stated.

[0038] When the position relation between two parts is described using the terms such as “on”, “above”, “below”, and “next”, one or more parts maybe positioned between the two parts unless the terms are used with the term “immediately” or “directly”.

[0039] When an element or layer is referred to as being “on” another element or layer, it maybe directly on the other element or layer, or intervening elements or layers may be present.

[0040] Although the terms “first”, “second”, and the like are used for describing various components, these components are not confined by these terms. These terms are merely used for distinguishing one component from the other components. Therefore, a first component to be mentioned below may be a second component in a technical concept of the present disclosure.

[0041] Throughout the whole specification, the same reference numerals denote the same elements.

[0042] Since size and thickness of each component illustrated in the drawings are represented for convenience in explanation, the present disclosure is not necessarily limited to the illustrated size and thickness of each component.

[0043] The features of various embodiments of the present disclosure can be partially or entirely bonded to or combined with each other and can be interlocked and operated in technically various ways, and the embodiments can be carried out independently of or in association with each other.

[0044] The present disclosure relates to a poly(meth)acrylate salt-based polymer absorbent for removing siloxane compounds in biogas, a method for removing siloxane compounds in biogas using the same, and a manufacturing apparatus therefor.

[0045] In the present disclosure, a poly(meth)acrylate salt-based polymeric material prepared through ion exchange of sodium poly(meth)acrylate is used as the absorbent of the siloxane compounds.

[0046] Hereinafter, the present disclosure will be described in more detail.

[0047] According to an exemplary embodiment of the present disclosure, the polymer absorbent uses a poly(meth)acrylate-based super absorbing polymeric material.

[0048] According to an exemplary embodiment of the present disclosure, the polymer absorbent is repetitively usable through a desorption reproduction process of the siloxane compounds.

[0049] According to an exemplary embodiment of the present disclosure, the polymer absorbent is prepared by ion exchange of sodium poly(meth)acrylate.

[0050] In the ion exchange, hygroscopic inorganic particles, such as metal chlorides such as LiCl, NaCl, KCl, MgCl.sub.2, and CaCl.sub.2, metal halides such as bromide or iodide are mixed with particles of sodium polyacrylate and the inorganic salt particles may be mixed between the sodium polyacrylate particles, and then sodium ions are exchanged to other cations by deliquescing the inorganic salt molecules by heating and humidifying to prepare the polymer absorbent.

[0051] According to an exemplary embodiment of the present disclosure, the polymer absorbent finally prepared through the ion exchange is supported in a porous honeycomb material.

[0052] According to an exemplary embodiment of the present disclosure, when the concentration of the siloxane compounds in the biogas is equal to or less than 200 ppm, a removal rate of siloxane is equal to or greater than 99%.

[0053] According to an exemplary embodiment of the present disclosure, a method for removing siloxane compounds in biogas includes steps of (a) providing biogas; and (b) passing the biogas through the polymer absorbent.

[0054] According to an exemplary embodiment of the present disclosure, the step (b) includes absorbing the siloxane compounds in the polymer absorbent in a temperature range of 15 to 30° C.

[0055] According to an exemplary embodiment of the present disclosure, the method further include desorbing the siloxane compounds absorbed in the polymer absorbent in a temperature range of 60 to 100° C., after the absorbing step.

[0056] According to an exemplary embodiment of the present disclosure, an apparatus for removing siloxane compounds in biogas performs a reproduction process by performing desorbing the polymer absorbent by using engine waste heat.

[0057] According to an exemplary embodiment of the present disclosure, the apparatus for removing the siloxane compounds in the biogas continuously operates by alternately absorbing and desorbing by constituting a siloxane compound absorbing unit as one or more multistage.

[0058] According to an exemplary embodiment of the present disclosure, the apparatus for removing the siloxane compounds in the biogas further includes one or more units selected from a water removing unit, a sulfur compound removing unit, a nitride oxide removing unit, a pressing unit, a decompressing unit, and a particle filter unit.

[0059] Next, Preparation Example and Examples of the present disclosure will be described. However, the following Preparation Example and Examples are to exemplify the present disclosure and the present disclosure is not limited to the following Preparation Example and Examples.

Preparation Example

[0060] A polymer absorbent according to the present disclosure used ion-exchanged poly(meth)acrylate salt which was known as a super absorbing polymer.

[0061] In order to prepare the polymer absorbent, sodium polyacrylate particles having an average diameter of 50 μm was used and mixed and added with lithium chloride particles having an average diameter of 30 μm with a weight ratio of 1:2 in a mixing chamber, and then deliquesced while being mixed well for 3 hr at a temperature of 60° C. in humidity of 100% to obtain an ion-exchanged deliquescent material. In addition, the ion-exchanged deliquescence was sufficiently dried in a dryer and grinded again to obtain particles of the ion-exchanged polyacrylate salt.

[0062] Next, the ion-exchanged polyacrylate salt was dissolved in distilled water at a concentration of 30 wt % and then coated on a polyethylene fiber nonwoven sheet having bent portions waved in a lateral direction and a thickness of 0.08 mm while flowing the deliquescence to manufacture a polymer absorbent product of the present disclosure. A coated thickness of the finally prepared polyacrylate salt is about 50 mm and about 44 g per 1 m.sup.2 is coated.

Example 1

[0063] Absorption performance of silicagel which is known as an existing siloxane absorbent was compared with that of a reusable polymer absorbent according to the present disclosure prepared according to Preparation Example at room temperature (25° C.). A pollutant to be evaluated was used by preparing siloxane simulator gas in biogas by heating, at 100° C. and 1 atm, a liquid siloxane compound as decamethylcyclopentasiloxane (D5) represented by the following Chemical Formula (1).

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[0064] Thereafter, as illustrated in FIG. 2, in the case of the reusable polymer absorbent, it was verified that the ability (absorption performance per unit weight) to remove the siloxane similar to silicagel was shown.

Example 2

[0065] Desorption (reproduction) performance according a reproduction (heating) temperature of a reusable polymer absorbent at a low temperature according to the present disclosure was compared with that of silicagel known as an existing siloxane absorbent. As illustrated in FIG. 3, it was verified that the reusable polymer absorbent at the low temperature according to the present disclosure had excellent desorption performance to such an extent that the siloxane removal rate reached 99% even in the case where the desorption test was performed at a low temperature (60° C.) and in a nitrogen atmosphere of normal pressure while the absorbent layer was heated at 60° C. Accordingly, it can be seen that in the case of silicagel which is an absorption and desorption material for removing the existing siloxane compounds, even at 150° C., the desorption performance is almost not shown, but the reusable polymer absorbent according to the present disclosure has very excellent reproduction performance.

[0066] Although the exemplary embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and may be embodied in many different forms without departing from the technical concept of the present disclosure. Therefore, the exemplary embodiments of the present disclosure are provided for illustrative purposes only but not intended to limit the technical concept of the present disclosure. The scope of the technical concept of the present disclosure is not limited thereto. Therefore, it should be understood that the above-described exemplary embodiments are illustrative in all aspects and do not limit the present invention. The protective scope of the present disclosure should be construed based on the following claims, and all the technical concepts in the equivalent scope thereof should be construed as falling within the scope of the present disclosure.