Method for treating sewage sludge and method for preparing dimethyl ether and octamethylcyclotetrasiloxane from sewage sludge

Abstract

The present invention relates to a method for treating sewage sludge and a method for preparing dimethyl ether and octamethylcyclotetrasiloxane from sewage sludge, and, more specifically, to a method for treating sewage sludge, and a method for preparing dimethyl ether and octamethylcyclotetrasiloxane by dissolving dried sewage sludge in a solvent, and then adding strain powder and a carbon source and allowing same to stand, the method for treating sewage sludge comprising the steps of: dissolving dried sewage sludge in a solvent; producing a yeast strain, freeze-drying same, and then preparing strain powder; and adding the strain powder and a carbon source to the solution in which the sewage sludge is dissolved, and allowing same to stand.

Description

Method for treating sewage sludge and method for producing dimethyl ether and octamethylcyclotetrasiloxane from sewage sludge

[0001] The present invention relates to a method for treating sewage sludge generated at a sewage treatment plant using a carbon source and a strain, and a method for producing dimethyl ether and octamethylcyclotetrasiloxane from such sewage sludge.

[0002] Generally, sludge is a sediment that is produced when suspended matter in water is separated from the liquid during water purification, sewage, or wastewater treatment. Sewage sludge has a high moisture content and a high organic matter content, making it highly putrefactive and containing various pathogens, which causes foul odors and is harmful to public health and hygiene.

[0003] In particular, sewage sludge generated at sewage treatment plants amounts to more than 1.3 million tons annually due to the rapid increase in population density and economic development in urban areas.

[0004] Sewage sludge generated in this way has relied on being buried in the soil or dumped into the ocean. However, as it causes environmental pollution, the sludge, which has a high organic matter content and high moisture content, causes many problems such as leachate generation and the formation of soft ground after burial, so the treatment method by burial is also gradually being avoided.

[0005] In accordance with these environmental and social conditions, various methods for drying sewage sludge are being developed, and these methods basically have the principle of removing moisture by applying heat to the sludge to evaporate it.

[0006]

[0007] Meanwhile, even if the sludge is dried, the sludge itself does not disappear, so it cannot be said that the pollution-causing factors associated with the sludge have been completely eliminated.

[0008] Accordingly, technology is being developed to recycle sludge instead of discarding it.

[0009] A related prior art is a method for manufacturing artificial soil using purified water, sewage sludge, and pruning byproducts disclosed in Korean Registered Patent No. 10-2277637 (Publication date: July 15, 2021).

[0010] The present invention aims to provide a method to solve problems caused by sewage sludge and to solve the problem of waste utilization.

[0011]

[0012] In addition, the present invention aims to provide a method for producing dimethyl ether, which can be used as an alternative fuel, and octamethylcyclotetrasiloxane, which can be applied to the synthesis of rubber and plastics, from sewage sludge having a foul-smelling and harmful ketone structure.

[0013] The objectives of the present invention are not limited to those mentioned above, and other objectives and advantages of the present invention not mentioned may be understood from the following description and will be more clearly understood from the embodiments of the present invention.

[0014]

[0015] Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the patent claims.

[0016] To solve the aforementioned technical problem, the present invention provides a method for treating sewage sludge comprising the steps of: dissolving dried sewage sludge in a solvent; producing a yeast strain, freeze-drying it, and then preparing a strain powder; and adding the strain powder and a carbon source to the solution in which the sewage sludge is dissolved and allowing it to settle.

[0017]

[0018] It is preferable that the above-mentioned dried sewage sludge has a moisture content of 10 weight% or less.

[0019]

[0020] In the sewage sludge treatment method according to the present invention, it is preferable that the sewage sludge be dissolved in a solvent at a concentration of 5 to 50 mg / mL.

[0021]

[0022] The strain is Dekkera deamine KH3 deposited under accession number KSTC 14262 BP, and it is preferable to include the strain powder at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

[0023]

[0024] In addition, the carbon source is sugarcane molasses and may be included at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

[0025]

[0026] It is preferable that the above-mentioned state be carried out for 48 to 72 hours.

[0027]

[0028] In addition, the present invention provides a method for producing dimethyl ether, which can be used as an alternative fuel, and octamethylcyclotetrasiloxane, which can be applied to the synthesis of rubber and plastics, by dissolving dried sewage sludge in a solvent, adding strain powder and a carbon source, and allowing it to stand.

[0029]

[0030] It is preferable that the above sewage sludge has a moisture content of 10 weight% or less, and it is preferable that the above sewage sludge be dissolved in a solvent at a concentration of 5 to 50 mg / mL.

[0031]

[0032] The strain is Dekkera deamine KH3 deposited under accession number KSTC 14262 BP, and it is preferable to include the strain powder at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

[0033]

[0034] The carbon source is sugarcane molasses, and it is preferable that the carbon source be included at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

[0035]

[0036] It is preferable that the above-mentioned state be carried out for 48 to 72 hours.

[0037] The sewage sludge treatment method according to the present invention can treat sewage sludge in an environmentally friendly way by using only a carbon source and strain powder without using chemical products such as acids and bases.

[0038]

[0039] In addition, the method for producing dimethyl ether and octamethylcyclotetrasiloxane according to the present invention can produce dimethyl ether that can be used as an alternative fuel from sewage sludge, which is a substance with a strong odor and harmful ketone structure, and octamethylcyclotetrasiloxane that can be applied to rubber and plastic synthesis.

[0040] FIG. 1 is a graph showing the change in material according to the concentration of carbon source and strain powder as an area ratio in the sewage sludge treatment method according to the present invention (in FIG. 1, a: decera diamine KH3 0.5%, carbon source 0.5%, b: decera diamine KH3 0.5%, carbon source 1%, c: decera diamine KH3 0.5%, carbon source 2%, d: decera diamine KH3 1%, carbon source 0.5%, e: decera diamine KH3 1%, carbon source 1%, f: decera diamine KH3 1%, carbon source 2%, g: decera diamine KH3 2%, carbon source 0.5%, h: decera diamine KH3 2%, carbon source 1%, i: decera diamine KH3 2%, carbon source 2%).

[0041] FIG. 2 is a graph showing the amounts of substances generated from sewage sludge as area ratios in the sewage sludge treatment method according to the present invention (in FIG. 2, a: area ratio of 2-nonanone in comparative examples and examples, b: area ratio of dimethyl ether in comparative examples and examples, c: area ratio of octamethylcyclotetrasiloxane in comparative examples and examples, d: area ratio of 2-nonanone, dimethyl ether, and octamethylcyclotetrasiloxane in comparative examples and examples).

[0042] Figure 3 is a bar graph of normalized area values ​​by functional groups in the sewage sludge treatment method according to the present invention.

[0043] FIG. 4 is a graph showing the amount of dimethyl ether and octamethylcyclotetrasiloxane produced from sewage sludge according to the present invention as an area ratio according to settling time (Fig. 4 a: 24 hours, b: 48 hours, c: 72 hours, d: 96 hours).

[0044] FIG. 5 is a graph showing the amount of dimethyl ether and octamethylcyclotetrasiloxane produced from sewage sludge according to the present invention as an area ratio according to settling time (in FIG. 5, a: change in content of 2-nonanone according to settling time, b: change in content of dimethyl ether according to settling time, c: change in content of octamethylcyclotetraoxanol according to settling time).

[0045] Figure 6 is a bar graph of normalized area values ​​by functional groups according to settling time from sewage sludge according to the present invention.

[0046] The aforementioned objectives, features, and advantages will be described in detail below, and accordingly, a person skilled in the art to which the present invention pertains will be able to easily implement the technical concept of the present invention.

[0047] In describing the present invention, detailed descriptions of known technologies related to the present invention are omitted if it is determined that such descriptions could unnecessarily obscure the essence of the invention.

[0048] Hereinafter, preferred embodiments according to the present invention will be described in detail.

[0049] The present invention is not limited to the embodiments disclosed below but can be implemented in various different forms, and the embodiments provided are merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention.

[0050] Throughout the specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less, unless specifically stated otherwise.

[0051]

[0052] Hereinafter, the method for treating sewage sludge according to the present invention and the method for producing dimethyl ether and octamethylcyclotetrasiloxane from sewage sludge will be described in detail.

[0053]

[0054] The present invention provides a method for treating sewage sludge comprising the steps of: dissolving dried sewage sludge in a solvent; producing a yeast strain, freeze-drying it, and then preparing a strain powder; and adding the strain powder and a carbon source to the solution in which the sewage sludge is dissolved and allowing it to stand.

[0055] First, the method for treating sewage sludge according to the present invention includes the step of dissolving a solvent in dried sewage sludge.

[0056] The above sewage sludge is mainly composed of organic matter, microorganisms, inorganic matter, etc., and is generated during sewage treatment in which solid matter settles from wastewater during various treatment processes.

[0057] The sewage sludge used in the present invention is sewage sludge dried through processes such as sludge heating or dewatering, and has a moisture content of 10 weight% or less.

[0058] The above solvent may be distilled water, deionized water, etc., and it may be more preferable to use one that is pressurized sterilized.

[0059] It is preferable that the above sewage sludge be dissolved in a solvent at a concentration of 5 to 50 mg / mL.

[0060] When the above sewage sludge is dissolved at a concentration of less than 5 mg / mL, a large amount of carbon source and strain powder is used compared to the amount of sewage sludge to be neutralized, which is undesirable in terms of neutralization efficiency, and when the concentration of sewage sludge exceeds 50 mg / mL, there is a problem that the neutralization effect is reduced.

[0061]

[0062] Next, the method for treating sewage sludge according to the present invention includes the step of producing a yeast strain, freeze-drying it, and then manufacturing it into a strain powder.

[0063] At this time, the strain is Dekkera deamine KH3, a Brettanomyces strain deposited under accession number KSTC 14262 BP, and was deposited at the National Institute of Biotechnology and Bioengineering (NIBB) Biological Resource Center under accession number KCTC14262BP on August 6, 2020.

[0064]

[0065] The method for treating sewage sludge according to the present invention includes the step of adding the strain powder and carbon source to the solution in which the sewage sludge is dissolved and allowing it to settle.

[0066] It is preferable that the strain powder be included at a concentration of 5 to 20 mg / mL relative to the total volume of the solution in which the sewage sludge is dissolved.

[0067] If the concentration of the above strain powder is less than 5 mg / mL, there is a problem that the detoxification efficiency of sewage sludge is low, and if it exceeds 20 mg / mL, there is a problem that the detoxification effect is reduced compared to the strain powder used.

[0068]

[0069] In addition, the carbon source may be selected from the group consisting of glycerol, xylose, glucose, sucrose, and sugarcane molasses, and it is preferable that the carbon source be included at a concentration of 5 to 20 mg / mL relative to the total volume of the solution in which the sewage sludge is dissolved.

[0070] If the above concentration is less than 5 mg / mL, there is a problem that the sewage sludge is not neutralized, and if the concentration exceeds 20 mg / mL, there is a problem that the neutralization effect of the sewage sludge is reduced.

[0071] It is preferable that the above period be 48 to 72 hours.

[0072] If the above-mentioned period is less than 48 hours, there is a problem of bad odor because ketones such as 2-nonanone contained in sewage sludge are not treated, and if it exceeds 72 hours, there is a problem of reduced content of dimethyl ether and octamethylcyclotetrasiloxane.

[0073]

[0074] In addition, the present invention provides a method for producing dimethyl ether and octamethylcyclotetrasiloxane by dissolving dried sewage sludge and then adding strain powder and a carbon source.

[0075] In the method for producing dimethyl ether and octamethylcyclotetrasiloxane according to the present invention, 2-nonanone is present in the sewage sludge at 57.28 wt%, 2-undecanone at 8.86 wt%, and 2-decanone at 4.52 wt%, and these ketone compounds are the main volatile substances of the sewage sludge.

[0076]

[0077] By adding the strain powder according to the present invention and a carbon source to the sewage sludge as described above, the content of the aforementioned ketone decreases rapidly, and the content of dimethyl ether and octamethylcyclotetrasiloxane increases.

[0078] To maximize the content of these dimethyl ethers and octamethylcyclotetrasiloxanes and to maximize the detoxification of sewage sludge, a settling process of 48 to 72 hours is required.

[0079] The above dimethyl ether (DME) can be used as a promising alternative fuel for internal combustion engines due to its potential to reduce exhaust emissions and improve efficiency.

[0080] DME is environmentally friendly because it can significantly reduce nitrogen oxide (NOx) and particulate matter emissions compared to fossil fuels.

[0081]

[0082] In addition, DME can be mixed with liquefied petroleum gas for use in spark ignition engines, which can significantly improve engine performance and greatly reduce exhaust emissions.

[0083]

[0084] In addition, octamethylcyclotetrasiloxane (D4), a versatile compound, is widely used across industries, but in the semiconductor industry, ultra-high purity D4 is very important for manufacturing SiCOH films with low dielectric constant, and its purification can be improved by new methods such as simultaneous distillation-extraction.

[0085]

[0086] In addition, D4 can be used as a precursor for an anti-fogging coating using atmospheric pressure dielectric barrier discharge.

[0087]

[0088] Example 1: Treatment of sewage sludge 1

[0089] Incineration ash and sugarcane molasses as a carbon source were purchased from commercial suppliers. Yeast strains were produced in-house on a large scale, freeze-dried, and then ground into powder.

[0090] Sewage sludge was dissolved at a concentration of 25 mg / mL (2.5%), sugarcane molasses was prepared at 5 mg / mL, and Dekkera deamine KH3 powder at the same concentration was used with pressurized distilled water to make the final volume 5 mL.

[0091] Sewage sludge, sugarcane molasses, and decera diamine were thoroughly mixed and left to stand at room temperature for 24 to 96 hours.

[0092]

[0093] Example 2: Treatment of sewage sludge 2

[0094] The mixture was prepared in the same manner as in Example 1 above, except that the concentration of sugarcane molasses was changed to 10 mg / mL (1%).

[0095]

[0096] Example 3: Treatment of sewage sludge 3

[0097] The mixture was prepared in the same manner as in Example 1 above, except that the concentration of sugarcane molasses was modified to 20 mg / mL (2%).

[0098]

[0099] Example 4: Treatment of sewage sludge 4

[0100] The mixture was prepared in the same manner as in Example 1, except that the concentration of decera diamine KH3 was changed to 10 mg / mL (1%).

[0101]

[0102] Example 5: Treatment of sewage sludge 5

[0103] The mixture was prepared in the same manner as in Example 1 above, except that the concentration of sugarcane molasses was changed to 10 mg / mL (1%) and the concentration of decera diamine KH3 was changed to 10 mg / mL (1%).

[0104]

[0105] Example 6: Treatment of sewage sludge 6

[0106] The mixture was prepared in the same manner as in Example 1 above, except that the concentration of sugarcane molasses was changed to 10 mg / mL (1%) and the concentration of decera diamine KH3 was changed to 20 mg / mL (1%).

[0107]

[0108] Example 7: Treatment of sewage sludge 7

[0109] The mixture was prepared in the same manner as in Example 1, except that the concentration of decera diamine KH3 was changed to 20 mg / mL (2%).

[0110]

[0111] Example 8: Treatment of sewage sludge 8

[0112] The mixture was prepared in the same manner as in Example 1 above, except that the concentration of sugarcane molasses was changed to 10 mg / mL (1%) and the concentration of decera diamine KH3 was changed to 20 mg / mL (2%).

[0113]

[0114] Example 9: Detoxification of sewage sludge 9

[0115] The mixture was prepared in the same manner as in Example 1 above, except that the concentration of sugarcane molasses was changed to 20 mg / mL (2%) and the concentration of decera diamine KH3 was changed to 20 mg / mL (2%).

[0116]

[0117] Comparative Example 1

[0118] A control group was prepared by dissolving sewage sludge at a concentration of 25 mg / mL (2.5%). Table 1 below shows the substances and content constituting Examples 1 to 9 and Comparative Example 1 above.

[0119] Wastewater Sludge (mg / mL) Strain Powder (mg / mL) Carbon Source (mg / mL) Example 1 2555 Example 2 25510 Example 3 25520 Example 4 25105 Example 5 251010 Example 6 251020 Example 7 25205 Example 8 252010 Example 9 252020 Comparative Example 125--

[0120]

[0121] Experiment 1: Analysis of Material Changes According to the Concentration of Strain Powder and Carbon Source

[0122] In the sewage sludge treatment method according to the present invention, changes in matter according to the concentration of strain powder and carbon source were analyzed, and the results are shown in FIGS. 1, 2, and 3.

[0123] FIG. 1 is a graph showing the change in material according to the concentration of carbon source and strain powder as an area ratio in the sewage sludge treatment method according to the present invention (in FIG. 1, a: decera diamine KH3 0.5%, carbon source 0.5%, b: decera diamine KH3 0.5%, carbon source 1%, c: decera diamine KH3 0.5%, carbon source 2%, d: decera diamine KH3 1%, carbon source 0.5%, e: decera diamine KH3 1%, carbon source 1%, f: decera diamine KH3 1%, carbon source 2%, g: decera diamine KH3 2%, carbon source 0.5%, h: decera diamine KH3 2%, carbon source 1%, i: decera diamine KH3 2%, carbon source 2%), with sugarcane molasses and decera diamine KH3 Shows the chromatogram of the treated sewage sludge.

[0124] In the sewage sludge treatment method according to the present invention, distinct differences in the chemical profiles of sewage sludge according to the concentrations of strain powder and carbon source were found, as in Examples 1 to 9 and Comparative Example 1.

[0125] In Comparative Example 1, which consisted only of sewage sludge, the most abundant compounds were ketones such as 2-nonanone (57.28%), 2-undecanone (8.86%), and 2-decanone (4.52%). These ketone compounds were the main components of the volatile profile of the untreated sewage sludge.

[0126] Other compounds detected in smaller proportions included siloxanes such as octamethylcyclotetrasiloxane (4.42%) and hexamethylcyclotrisiloxane (1.82%), and other volatile substances such as benzaldehyde (1.03%) and 2-nonanol (0.95%).

[0127] In contrast, sewage sludge treated with sugarcane molasses and decera diamine KH3 powder showed significant changes in its volatility profile.

[0128]

[0129] FIG. 2 is a graph showing the amounts of substances generated from sewage sludge in the sewage sludge treatment method according to the present invention as area ratios (in FIG. 2, a: area ratio of 2-nonanone in comparative examples and examples, b: area ratio of dimethyl ether in comparative examples and examples, c: area ratio of octamethylcyclotetrasiloxane in comparative examples and examples, d: area ratio of 2-nonanone, dimethyl ether, and octamethylcyclotetrasiloxane in comparative examples and examples), showing the area percentages of 2-nonanone, dimethyl ether, and octamethylcyclotetrasiloxane in all of Comparative Example 1 and Examples 1 to 9, and showing the differences in the relative presence of these compounds across the sample groups. The most noticeable change is the significant increase in dimethyl ether (DME) and octamethylcyclotetrasiloxane for all examples.

[0130] For example, in examples containing sewage sludge, 10 mg / mL (1%) of sugarcane molasses, and 10 mg / mL (1%) of decera diamine KH3 powder, the most abundant compounds were dimethyl ether (28.51%) and octamethylcyclotetrasiloxane (16.84%), and other components such as ethyl acetate (5.50%) and hexamethylcyclotrisiloxane (3.35%) also appeared in the profile.

[0131] Examples containing 10 mg / mL of sugarcane molasses and 10 mg / mL of decera diamine KH3 powder contained high amounts of dimethyl ether and octamethylcyclotetrasiloxane, which are compounds that are absent or present in minimal amounts in Comparative Example 1.

[0132]

[0133] FIG. 3 is a bar graph of normalized area values ​​by functional groups in the sewage sludge treatment method according to the present invention, showing the normalized area values ​​(%) of functional groups in Comparative Example 1 and Examples 1 to 9, and also showing the differences in functional group composition between sample groups.

[0134] This indicates that the microbial conversion ability of the Brettanomyces strain Dekeradiamine KH3 is excellent.

[0135] Specifically, the dominant ketones in Comparative Example 1, such as 2-nonanone and 2-undecanone, were effectively reduced and converted into dimethyl ether and other siloxane compounds. This change highlights the role of dekeradiamine KH3 in leading the bioconversion process facilitated by the addition of sugarcane molasses as a carbon source.

[0136]

[0137] Experimental Example 2: Analysis of changes in components according to settling time

[0138] Changes in components according to settling time in the sewage sludge treatment method according to the present invention were analyzed, and the results are shown in FIGS. 4, 5, and 6.

[0139] Analysis of time-based samples showed notable changes in the volatility profiles of the Examples and Comparative Example 1.

[0140] In Comparative Example 1, the control group, the ketone compound 2-nonanone was consistently present at all times.

[0141] In the examples according to the present invention, the area ratio of 2-nonanone was such that no 2-nonanone was present due to the treatment of the strain and carbon source.

[0142]

[0143] FIG. 4 is a graph showing the amount of dimethyl ether and octamethylcyclotetrasiloxane produced from sewage sludge according to the present invention as an area ratio according to the settling time (Fig. 5 a: 24 hours, b: 48 hours, c: 72 hours, d: 96 hours), and FIG. 4 shows chromatograms of sewage sludge treated at different times using the strain and carbon source according to the present invention.

[0144] When sewage sludge was treated with 10 mg / mL (1%) sugarcane molasses and 10 mg / mL (1%) decera diamine KH3 powder, 2-nonanone was completely removed, which represents a shift in the volatility profile from Comparative Example 1. This suggests a reduction in ketones, which are often associated with undesirable odors, for a more favorable compound.

[0145] With respect to dimethyl ether (DME), it was not present in Comparative Example 1 at all points in time.

[0146] In Examples 1 to 9, there were slight variations in the production of dimethyl ether. At 24 hours, the production of dimethyl ether was highest at 20.40% and decreased to 17.53% at 48 hours. At 72 hours, the production of DME peaked again at 23.34% but dropped slightly to 19.29% at 96 hours. This indicates that the production of DME is most pronounced at the 72-hour mark and then decreases at 96 hours.

[0147]

[0148] FIG. 5 is a graph showing the amount of dimethyl ether and octamethylcyclotetrasiloxane produced from sewage sludge according to the present invention as an area ratio according to settling time (in FIG. 5, a: change in content of 2-nonanone according to settling time, b: change in content of dimethyl ether according to settling time, c: change in content of octamethylcyclotetrasiloxane according to settling time), and shows the area percentages of 2-nonanone, dimethyl ether and octamethylcyclotetrasiloxane (D4) in Comparative Example 1 and various time-based treatment samples.

[0149] In Comparative Example 1, the presence of D4 gradually increased from 24 hours to 48 hours (10.9% and 13.65%, respectively), and then remained constant at 72 hours and 96 hours (13.2% and 13.4%).

[0150] In the embodiments according to the present invention, the generation of D4 showed a slight decrease over time. At 24 and 48 hours, the percentage of the area of ​​D4 did not change (20.33% and 20.02%, respectively).

[0151] However, after 72 hours, the rate decreased to 15.10%, and after 96 hours, it decreased further to 13.96%.

[0152] This gradual decrease in D4 indicates that although the yield is lower compared to DME, it does not disappear completely like 2-nonanone.

[0153]

[0154] FIG. 6 is a bar graph of normalized area values ​​by functional groups over time from sewage sludge according to the present invention, and shows the normalized area percentage (%) of functional groups in Comparative Example 1 and embodiments according to the present invention.

[0155] These values ​​show changes in the functional group composition over time and represent the temporal variation of the volatility profile due to the detoxification process.

[0156]

[0157] Although the present invention has been described above with reference to the illustrated drawings, the present invention is not limited by the embodiments and drawings disclosed in this specification, and it is obvious that various modifications can be made by a person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration according to the present invention were not explicitly described while describing the embodiments of the present invention above, it is natural to acknowledge that the effects predictable by said configuration should also be recognized.

Claims

1. A step of dissolving dried sewage sludge in a solvent; A step of producing a mother strain, freeze-drying it, and then preparing strain powder; and A method for treating sewage sludge, comprising the step of adding the strain powder and carbon source to the solution in which the sewage sludge is dissolved and allowing it to settle.

2. In Paragraph 1, A method for treating sewage sludge characterized in that the above-described dried sewage sludge has a moisture content of 10 weight% or less.

3. In Paragraph 1, A method for treating sewage sludge characterized in that the above sewage sludge is dissolved in a solvent at a concentration of 5 to 50 mg / mL.

4. In Paragraph 1, A method for treating sewage sludge characterized in that the strain is Dekkera deamine KH3, deposited under accession number KCTC 14262 BP.

5. In Paragraph 1, A method for treating sewage sludge, characterized in that the carbon source is selected from the group consisting of glycerol, xylose, glucose, sucrose, and sugarcane molasses.

6. In Paragraph 1, A method for treating sewage sludge characterized by including the strain powder at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

7. In Paragraph 1, A method for treating sewage sludge characterized in that the carbon source is included at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

8. In any one of paragraphs 1 through 7, A method for treating sewage sludge characterized by the above-mentioned state being performed for 48 to 72 hours.

9. A method for producing dimethyl ether and octamethylcyclotetrasiloxane by dissolving dried sewage sludge in a solvent, adding strain powder and a carbon source, and allowing it to stand.

10. In Paragraph 9, A method characterized by the above sewage sludge being dissolved at a concentration of 5 to 50 mg / mL.

11. In Paragraph 9, A method characterized in that the strain is Dekkera deamine KH3, deposited under accession number KCTC 14262 BP.

12. In Paragraph 9, A method characterized by including the strain powder at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

13. In Paragraph 9, A method characterized in that the carbon source is selected from the group consisting of glycerol, xylose, glucose, sucrose, and sugarcane molasses.

14. In Paragraph 9, A method characterized by including the carbon source at a concentration of 5 to 20 mg / mL relative to the total volume of the sewage sludge.

15. In any one of paragraphs 9 through 14, A method characterized by the above-mentioned state being performed for 48 to 72 hours.

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