Escherichia coli for reducing sulfur content of coal, coal desulfurization method and application thereof

Abstract

The invention relates to escherichia coli for reducing the sulfur content of coal, a coal desulfurization method and application thereof, and belongs to the technical field of coal resource utilization. The Escherichia coli capable of reducing the sulfur content of the coal, disclosed by the invention, is an Escherichia coli 2065801 strain; the coal desulfurization method comprises the following steps: mixing coal and sulfuric acid, filtering, cleaning, precipitating and drying to obtain pretreated coal; and carrying out mixed culture on the pretreated coal and the escherichia coli liquid, filtering, drying and precipitating to obtain the desulfurized coal. The Escherichia coli 2065801 strain and the coal desulfurization method have the advantages that the operation is simple, the cost is low, the desulfurization energy consumption is low, the desulfurization efficiency is high, the method is green and environment-friendly, and secondary pollution cannot be caused.

Description

Technical Field

[0001] The present invention relates to the technical field of coal resource utilization, and in particular to an Escherichia coli for reducing the sulfur content of coal and a coal desulfurization method and applications thereof. Background Art

[0002] my country has abundant coal resources, which are widely distributed and of various types. However, the geological conditions in some areas are complex, the coal quality is poor, and it is high-sulfur, high-ash coal with high gas content. The sulfur content in coal is unevenly distributed. Generally speaking, the sulfur content in coal in the southern mining area is higher, and the sulfur content in coal in the northern mining area is lower; the sulfur content in deep coal seams is higher, and the sulfur content in shallow coal seams is lower; the sulfur content in coal with high metamorphism is high, and the sulfur content in coal with low metamorphism is low. my country has more than 100.24 billion tons of coal reserves, of which high-sulfur coal reserves account for about 9.0% of the country's coal resources.

[0003] Sulfur-containing coal will release a large amount of sulfur dioxide during the combustion process, which not only harms human health and leads to an increase in respiratory diseases, but also causes corrosion and damage to buildings and cultural relics. Sulfur dioxide is also one of the main culprits of acid rain, which further causes serious damage to the soil, water bodies and ecosystems. In addition, the mining and use of sulfur-containing coal will also cause land destruction, water resource pollution and other hazards to the environment.

[0004] At present, traditional coal desulfurization methods usually rely on physical or chemical methods. Although these methods can effectively reduce the sulfur content in coal, they still have problems such as high cost, high energy consumption, complex operation, and easy secondary pollution to the environment. There is no economical, environmentally friendly, efficient and convenient coal desulfurization method based on microorganisms in the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide an Escherichia coli and coal desulfurization method for reducing the sulfur content of coal and its application, so as to solve the problems of high cost, high energy consumption, complex operation and easy secondary pollution to the environment in the prior art of coal desulfurization.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides an Escherichia coli for reducing the sulfur content of coal. The Escherichia coli is an Escherichia coli 2065801 strain, which is deposited in the General Microbiology Center of China National Committee for the Preservation of Microorganisms, with the address at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing. The preservation date is September 2, 2024, and the preservation number is CGMCC No. 31819.

[0008] The present invention also provides a coal sulfur pollution removal bacteria agent, and the coal sulfur pollution removal bacteria agent comprises the Escherichia coli.

[0009] The present invention also provides a coal desulfurization method, comprising the following steps:

[0010] (1) Mixing coal and sulfuric acid for 0.5 to 2 hours, filtering, washing the precipitate until the pH is 6.5 to 7.5, and drying to obtain pretreated coal;

[0011] (2) mixing the pretreated coal described in step (1) with the Escherichia coli bacterial solution, culturing for 10 to 20 days, filtering, taking the precipitate and drying it to obtain desulfurized coal;

[0012] The Escherichia coli bacterial liquid is a bacterial liquid prepared using the Escherichia coli.

[0013] Preferably, the mass volume ratio of the mixture of coal and sulfuric acid in step (1) is 5-15 g:100 mL;

[0014] The particle size of the coal in step (1) is 120-140 mesh;

[0015] The pH of the sulfuric acid in step (1) is 2 to 4;

[0016] The drying in step (1) is vacuum drying, the vacuum drying temperature is 30 to 50° C., and the vacuum drying time is 36 to 60 hours.

[0017] Preferably, the method for preparing the Escherichia coli liquid in step (2) comprises the following steps: inoculating Escherichia coli into a fermentation medium, and fermenting and culturing for 6 to 10 hours to obtain the Escherichia coli liquid.

[0018] Preferably, the volume ratio of the Escherichia coli to the fermentation medium is 0.5-3 g:100 mL;

[0019] The fermentation medium is LB medium.

[0020] Preferably, the fermentation temperature is 30-40°C, and the fermentation speed is 150-200 rpm.

[0021] Preferably, the mass volume ratio of the pretreated coal and the Escherichia coli liquid mixed in step (2) is 0.5-2 g: 80-120 mL;

[0022] The initial live bacterial concentration of the E. coli solution in step (2) is 2×10 8 ~5×10 8 cfu / mL.

[0023] Preferably, the culture temperature in step (2) is 30-40° C., and the culture speed is 150-200 rpm;

[0024] The drying in step (2) is vacuum drying, the vacuum drying temperature is 30 to 50° C., and the vacuum drying time is 36 to 60 hours.

[0025] The invention also provides application of the coal desulfurization method in reducing the sulfur content of coal.

[0026] The present invention has the following technical effects and advantages:

[0027] (1) The Escherichia coli 2065801 strain of the present invention has strong activity and adaptability, can tolerate and adapt to the complex living environment of sulfur-containing coal, and exhibits the characteristics of high growth rate and high reproduction rate;

[0028] (2) The Escherichia coli 2065801 strain of the present invention can reduce the content of hydroxyl groups, ether bonds and sulfides in coal, and convert sulfur in coal into an easily removable form through biochemical reactions, thereby efficiently removing sulfur from coal;

[0029] (3) The coal desulfurization method of the present invention first oxidizes the coal with sulfuric acid, and uses vacuum drying to retain the oxidative properties of the pretreated coal, and then mixes the pretreated coal with the Escherichia coli XX strain with sulfur pollution removal function, thereby efficiently removing sulfur from the coal and reducing the pollutant content in the coal. The method has the characteristics of simple operation, low cost, low desulfurization energy consumption, high desulfurization efficiency, green environmental protection, and no secondary pollution.

[0030] (4) The coal desulfurization method of the present invention combines microbial technology with clean coal technology, successfully reducing the sulfur content in coal, thereby reducing the environmental pollution caused by sulfur oxide emissions, improving the fuel calorific value and combustion efficiency of coal, realizing the green utilization of coal resources, and facilitating the sustainable development of the coal chemical industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the apparent morphology of Escherichia coli 2065801 strain on a plate.

[0032] Collection Instructions

[0033] The Escherichia coli is Escherichia coli 2065801 strain, which is deposited in the General Microbiology Center of China Culture Collection Administration, located at No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. The deposit date is September 2, 2024, and the deposit number is CGMCC No.31819. DETAILED DESCRIPTION

[0034] The present invention provides an Escherichia coli for reducing the sulfur content of coal. The Escherichia coli is an Escherichia coli 2065801 strain, which is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration, with an address of No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, a deposit date of September 2, 2024, and a deposit number of CGMCC No. 31819.

[0035] The present invention also provides a coal sulfur pollution removal bacteria agent, and the coal sulfur pollution removal bacteria agent comprises the Escherichia coli.

[0036] The present invention also provides a coal desulfurization method, comprising the following steps:

[0037] (1) Mixing coal and sulfuric acid for 0.5 to 2 hours, preferably 1 hour, filtering, washing the precipitate until the pH is 6.5 to 7.5, preferably 7, and drying to obtain pretreated coal;

[0038] (2) mixing the pretreated coal described in step (1) with the Escherichia coli bacterial solution, culturing for 10 to 20 days, preferably 15 days, filtering, taking the precipitate and drying it to obtain desulfurized coal;

[0039] The Escherichia coli bacterial liquid is a bacterial liquid prepared using the Escherichia coli.

[0040] In the present invention, the step (1) further includes drying the coal before mixing the coal and sulfuric acid;

[0041] The drying is vacuum drying, the vacuum drying temperature is 30-50° C., preferably 40° C.; the vacuum drying time is 36-60 hours, preferably 48 hours.

[0042] In the present invention, the mass volume ratio of the mixture of coal and sulfuric acid in step (1) is 5-15 g:100 mL, preferably 10 g:100 mL;

[0043] The particle size of the coal in step (1) is 120-140 mesh, preferably 130 mesh;

[0044] The pH of the sulfuric acid in step (1) is 2 to 4, preferably 3;

[0045] The drying in step (1) is vacuum drying, the vacuum drying temperature is 30-50° C., preferably 40° C.; the vacuum drying time is 36-60 h, preferably 48 h.

[0046] In the present invention, the method for preparing the Escherichia coli liquid in step (2) comprises the following steps: inoculating Escherichia coli into a fermentation medium, and fermenting and culturing for 6 to 10 hours, preferably 8 hours, to obtain the Escherichia coli liquid.

[0047] In the present invention, the volume ratio of the Escherichia coli to the fermentation medium is 0.5-3 g:100 mL, preferably 1 g:100 mL;

[0048] The fermentation medium is LB medium;

[0049] The LB medium uses water as solvent and includes the following components in concentrations: 5-15 g / L tryptone, preferably 10 g / L; 3-7 g / L yeast extract, preferably 5 g / L; 15-20 g / L sodium chloride, preferably 18 g / L; pH is 6.5-7.5, preferably 7.0.

[0050] In the present invention, the temperature of the fermentation culture is 30-40°C, preferably 37°C; the rotation speed of the fermentation culture is 150-200 rpm, preferably 180 rpm.

[0051] In the present invention, the mass volume ratio of the pretreated coal and the Escherichia coli liquid mixed in step (2) is 0.5-2 g: 80-120 mL, preferably 0.8-1.5 g: 90-110 mL, and more preferably 1 g: 105 mL;

[0052] The initial live bacterial concentration of the E. coli solution in step (2) is 2×10 8 ~5×10 8 cfu / mL, preferably 3×10 8 cfu / mL.

[0053] In the present invention, the culture temperature in step (2) is 30-40°C, preferably 37°C; the culture speed is 150-200 rpm, preferably 180 rpm;

[0054] The drying in step (2) is vacuum drying, and the vacuum drying temperature is 30-50° C., preferably 40° C.; the vacuum drying time is 36-60 h, preferably 48 h.

[0055] In the present invention, step (2) further comprises washing the precipitate with distilled water before drying.

[0056] The invention also provides application of the coal desulfurization method in reducing the sulfur content of coal.

[0057] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0058] In the embodiment of the present invention, the SHZ-D (III) type circulating water vacuum pump is purchased from Zhengzhou Kerui Instrument Equipment Co., Ltd.

[0059] Example 1: Coal desulfurization in Longfeng Coal Mine

[0060] (1) Coal collection and pretreatment: Coal was collected from Longfeng Coal Mine in Bijie City, Guizhou Province. The soil pH of the mine site was 5.5 and the annual average temperature of the mining area was 14.3°C. 30 g of the collected coal was crushed to a particle size of 130 mesh, vacuum dried at 40°C for 48 h to remove moisture, and then added with 300 mL of sulfuric acid with pH = 3 for 1 h. Then, it was filtered using a SHZ-D (III) type circulating water vacuum pump, and the precipitate was washed with distilled water to pH = 7, and then vacuum dried at 40°C for 48 h to retain the oxidative properties of the coal to obtain pretreated coal.

[0061] (2) Preparation of fermentation medium: 10 g of tryptone, 5 g of yeast extract and 5 g of sodium chloride were mixed in 1 L of water, the pH was adjusted to 7.0, and then sterilized by high pressure steam at 121°C for 20 min to obtain LB medium;

[0062] (3) Preparation of Escherichia coli culture liquid: 20 mL of Escherichia coli 2065801 strain was added to 200 mL of LB medium and fermented at 37°C and 180 rpm for 8 h to obtain an initial viable bacterial concentration of 3 × 10 8 cfu / mL of Escherichia coli liquid, the apparent morphology of Escherichia coli 2065801 strain is as follows Figure 1 As shown;

[0063] (4) Coal desulfurization: 1 g of pretreated coal was sterilized by ultraviolet irradiation for 1 h, then mixed with 105 mL of Escherichia coli culture solution, cultured at 37 °C and 180 rpm for 15 d, then filtered using a SHZ-D (III) circulating water vacuum pump and a Buchner funnel, washed with distilled water, and vacuum dried at 40 °C for 48 h to obtain desulfurized coal;

[0064] (5) Desulfurization result determination: The desulfurized coal was cleaned with distilled water. Referring to the literature of Cai Chuanchuan et al. (Cai Chuanchuan, Yang Minghu, Pan Lulu, et al. Study on the type and content of sulfur in coal samples of different densities based on XPS technology [J]. Coal Preparation Technology, 2018, (05): 56-59), the XPS analysis method was used to determine the relative contents of C, O, S and other elements on the surface of coal, pretreated coal and desulfurized coal collected from Longfeng Coal Mine, and the sulfur removal rate of coal was calculated. The results are shown in Table 1.

[0065] The calculation formula for sulfur removal rate is:

[0066]

[0067] Table 1 Relative content of elements on the surface of coal in Longfeng Coal Mine

[0068]

[0069] The results show that after pretreatment, the oxygen content of the coal from Longfeng Coal Mine decreased by 2.32% and the carbon content increased by 2.40%; after the pretreated coal was desulfurized by Escherichia coli liquid, the oxygen content of the coal decreased by 4.64% and the carbon content increased by 4.7%; the sulfur removal rate of the coal from Longfeng Coal Mine by Escherichia coli liquid was 45.16%.

[0070] Example 2: Coal Desulfurization in Yingpanhao Coal Mine

[0071] (1) Coal collection and pretreatment: Coal was collected from Yingpanhao Coal Mine in Tongren City, Guizhou Province. 30 g of the collected coal was crushed to a particle size of 120 mesh, vacuum dried at 30°C for 60 h to remove moisture, and then added with 300 mL of sulfuric acid with a pH of 2 for 0.5 h. Then, it was filtered using a SHZ-D (III) type circulating water vacuum pump, and the precipitate was washed with distilled water to a pH of 7, and then vacuum dried at 30°C for 60 h to retain the oxidative properties of the coal to obtain pretreated coal.

[0072] (2) Fermentation medium preparation: LB medium was prepared using the method described in Example 1;

[0073] (3) Preparation of Escherichia coli culture liquid: 20 mL of Escherichia coli 2065801 strain was added to 200 mL of LB medium and fermented at 37°C and 180 rpm for 6 h to obtain an initial viable bacterial concentration of 3 × 10 8 cfu / mL of Escherichia coli liquid, the apparent morphology of Escherichia coli 2065801 strain is as follows Figure 1 As shown;

[0074] (4) Coal desulfurization: 0.8 g of pretreated coal was sterilized by ultraviolet irradiation for 1 h, then mixed with 120 mL of Escherichia coli culture solution, cultured at 37 °C and 150 rpm for 20 d, then filtered using a SHZ-D (III) circulating water vacuum pump and a Buchner funnel, washed with distilled water, and vacuum dried at 30 °C for 60 h to obtain desulfurized coal;

[0075] (5) Desulfurization result determination: The sulfur removal rate of the coal from Yingpanhao Coal Mine was determined and calculated using the method described in Example 1. The results are shown in Table 2.

[0076] Table 2 Relative content of elements on the surface of coal in Yingpanhao Coal Mine

[0077]

[0078] The results show that after pretreatment, the oxygen content of the coal from Yingpanhao Coal Mine increased by 0.98% and the carbon content decreased by 1.06%; after the pretreated coal was desulfurized by Escherichia coli liquid, the oxygen content of the coal increased by 3.11% and the carbon content decreased by 2.63%; the sulfur removal rate of the coal from Yingpanhao Coal Mine by Escherichia coli liquid was 59.70%.

[0079] Example 3: Coal desulfurization in Qishuwan Coal Mine

[0080] (1) Coal collection and pretreatment: Coal was collected from Qishuwan Coal Mine in Ordos City, Inner Mongolia Autonomous Region. 30 g of the collected coal was crushed to a particle size of 140 mesh, vacuum dried at 50°C for 36 h to remove moisture, and then added with 300 mL of sulfuric acid with pH = 4 for 2 h. Then, it was filtered using a SHZ-D (III) type circulating water vacuum pump, and the precipitate was washed with distilled water to pH = 7, and then vacuum dried at 50°C for 36 h to retain the oxidative properties of the coal to obtain pretreated coal.

[0081] (2) Fermentation medium preparation: LB medium was prepared using the method described in Example 1;

[0082] (3) Preparation of Escherichia coli culture liquid: 20 mL of Escherichia coli 2065801 strain was added to 200 mL of LB medium and fermented at 37°C and 180 rpm for 10 h to obtain an initial viable bacterial concentration of 3 × 10 8 cfu / mL of Escherichia coli liquid, the apparent morphology of Escherichia coli 2065801 strain is as follows Figure 1 As shown;

[0083] (4) Coal desulfurization: 1.5 g of pretreated coal was sterilized by ultraviolet irradiation for 1 h, then mixed with 110 mL of Escherichia coli culture solution, cultured at 37 °C and 200 rpm for 10 d, then filtered using a SHZ-D (III) circulating water vacuum pump and a Buchner funnel, washed with distilled water, and vacuum dried at 50 °C for 36 h to obtain desulfurized coal;

[0084] (5) Desulfurization result determination: The sulfur removal rate of the coal from Qishuwan Coal Mine was determined and calculated using the method described in Example 1. The results are shown in Table 3.

[0085] Table 3 Relative content of elements on the surface of coal in Qishuwan Coal Mine

[0086]

[0087]

[0088] The results show that after pretreatment, the oxygen content of the coal from Qishuwan Coal Mine increased by 1.51% and the carbon content decreased by 1.36%; after the pretreated coal was desulfurized by Escherichia coli liquid, the oxygen content of the coal increased by 1.78% and the carbon content decreased by 1.53%; the sulfur removal rate of the coal from Qishuwan Coal Mine by Escherichia coli liquid was 41.67%.

[0089] As can be seen from the above embodiments, the present invention provides an Escherichia coli for reducing the sulfur content of coal and a coal desulfurization method and application thereof. The Escherichia coli 2065801 strain and the coal desulfurization method of the present invention can efficiently remove sulfur from coal and reduce the content of pollutants in coal, and have the characteristics of simple operation, low cost, low desulfurization energy consumption, high desulfurization efficiency, green environmental protection, and no secondary pollution.

[0090] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An Escherichia coli for reducing the sulfur content of coal, It is characterized in that The Escherichia coli is the Escherichia coli 2065801 strain, which is deposited in the General Microbiology Center of the China Culture Collection Administration, located at No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. The deposit date is September 2, 2024, and the deposit number is CGMCC No.31819.

2. A coal sulfur pollution removal agent, It is characterized in that The coal sulfur pollution removal agent includes the Escherichia coli described in claim 1.

3. A method for desulfurizing coal, It is characterized in that The steps include: (1) Mixing coal and sulfuric acid for 0.5 to 2 hours, filtering, washing the precipitate until the pH is 6.5 to 7.5, and drying to obtain pretreated coal; (2) mixing the pretreated coal described in step (1) with the Escherichia coli bacterial solution, culturing for 10 to 20 days, filtering, taking the precipitate and drying it to obtain desulfurized coal; The Escherichia coli bacterial liquid is a bacterial liquid prepared using the Escherichia coli described in claim 1.

4. The method for desulfurizing coal according to claim 3, It is characterized in that The mass volume ratio of the mixture of coal and sulfuric acid in step (1) is 5-15 g:100 mL; The particle size of the coal in step (1) is 120-140 mesh; The pH of the sulfuric acid in step (1) is 2 to 4; The drying in step (1) is vacuum drying, the vacuum drying temperature is 30 to 50° C., and the vacuum drying time is 36 to 60 hours.

5. The method for desulfurizing coal according to claim 3, It is characterized in that The preparation method of the Escherichia coli liquid in step (2) comprises the following steps: inoculating Escherichia coli into a fermentation medium, and fermenting and culturing for 6 to 10 hours to obtain the Escherichia coli liquid.

6. The method for desulfurizing coal according to claim 5, It is characterized in that The volume ratio of the Escherichia coli to the fermentation medium is 0.5-3 g:100 mL; The fermentation medium is LB medium.

7. The method for desulfurizing coal according to claim 6, It is characterized in that The fermentation temperature is 30-40°C, and the fermentation speed is 150-200 rpm.

8. The method for desulfurizing coal according to claim 3, It is characterized in that The mass volume ratio of the pretreated coal and the Escherichia coli liquid in step (2) is 0.5-2 g: 80-120 mL; The initial live bacterial concentration of the E. coli solution in step (2) is 2×10 8 ~5×10 8 cfu / mL.

9. The method for desulfurizing coal according to claim 3, It is characterized in that The culture temperature in step (2) is 30-40° C. and the culture speed is 150-200 rpm; The drying in step (2) is vacuum drying, the vacuum drying temperature is 30 to 50° C., and the vacuum drying time is 36 to 60 hours.

10. Use of the coal desulfurization method according to any one of claims 3 to 9 in reducing the sulfur content of coal.

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