A process for converting cut hair into methane
By pre-treating, crushing, sieving, mixing, catalyzing, and fermenting hair fragments, they are converted into high-purity methane, solving the problems of insufficient raw materials for methane production and environmental pollution, and realizing efficient and environmentally friendly methane production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HENAN CULTURED DIAMOND RESEARCH INSTITUTE CO LTD
- Filing Date
- 2026-03-02
- Publication Date
- 2026-06-09
AI Technical Summary
The limited and unstable supply of raw materials for methane production, the environmental pollution caused by hair removal methods, and the low biomass conversion efficiency result in high methane production costs and environmental problems.
Through hair pretreatment, crushing and sieving, raw material mixing and catalyst addition, anaerobic fermentation reaction and methane separation and purification steps, the broken hair is converted into methane. Activated carbon and nickel-based catalysts are used to improve reaction efficiency, and pressure swing adsorption and condensation treatment are used to improve methane purity.
It has enabled efficient and environmentally friendly methane production using hair clippings as raw material, solving the problems of unstable raw material supply and environmental pollution, improving methane conversion efficiency and purity, and making it suitable for large-scale industrial production.
Abstract
Description
Technical Field
[0001] This invention relates to the field of energy conversion technology, specifically to a process for converting hair clippings into methane. Background Technology
[0002] In the energy sector, methane, as a clean and efficient energy source, is widely used in various fields, including industry and civilian applications. Currently, methane production mainly relies on fossil fuels, such as natural gas extraction, and biomass fermentation. Fossil fuels are non-renewable resources, and their extraction and use not only face the problem of resource depletion but also cause environmental pollution, such as greenhouse gas emissions. While biomass fermentation has a degree of renewability, commonly used biomass raw materials, such as crop straw and livestock manure, present many inconveniences in collection, transportation, and storage, and the supply of raw materials is greatly limited by season and region.
[0003] Hair clippings are a common type of waste, originating from a wide range of sources, including large quantities generated by barbershops, textile factories, and other similar establishments. Currently, the main methods for disposing of hair clippings are landfill and incineration. Landfilling consumes a significant amount of land resources, and hair clippings are difficult to decompose naturally during the landfill process, potentially polluting the soil and groundwater. Incineration, on the other hand, produces large amounts of harmful gases, such as dioxins, causing serious air pollution.
[0004] The existing technology has the following shortcomings: (1) Raw material limitations: Existing raw materials for methane production, such as fossil fuels and some biomass raw materials, have problems such as limited resources, unstable supply or difficulty in collection. The non-renewable nature of fossil fuels determines that they cannot meet the demand for methane production in the long term; while biomass raw materials are greatly affected by seasons and regions, making it difficult to guarantee a continuous and stable supply, which increases the cost and uncertainty of methane production. (2) Environmental pollution problems: Traditional methods of handling hair clippings, such as landfill and incineration, have caused serious negative impacts on the environment. Landfill leads to the waste of land resources and pollution of soil and groundwater; the harmful gases produced by incineration not only pollute the atmospheric environment, but also pose a threat to human health. (3) Conversion efficiency problems: The existing biomass fermentation method has low conversion efficiency and long reaction cycle in the process of converting biomass into methane. This is mainly because the structure of biomass raw materials is complex and difficult to be rapidly decomposed and utilized by microorganisms, resulting in low methane yield and productivity, which limits its large-scale application. Summary of the Invention
[0005] The purpose of this invention is to provide a process for converting hair fragments into methane, in order to solve the problems of limited raw materials for existing methane production, environmental pollution from hair fragment treatment, and low biomass conversion efficiency, thereby realizing the resource utilization of hair fragments and providing a new, environmentally friendly, and efficient method for methane production.
[0006] Specifically, the technical solution provided by this invention is: a process for converting hair clippings into methane, comprising the following steps:
[0007] Step 1, Hair Pretreatment: Place the collected hair fragments in a washing tank, add a surfactant solution with a mass fraction of 0.5% - 1%, and stir and wash at 30 - 40℃ for 15 - 30 minutes to remove oil and impurities from the hair surface; then rinse with clean water until neutral, drain the water, and place in a drying device to dry at 60 - 80℃ until the moisture content is below 3%;
[0008] Step 2, Hair crushing and sieving: The dried hair fragments are fed into a crusher and crushed into powder with a particle size of less than 2 mm; then the crushed hair powder is sieved through a sieving device to select hair particles with a particle size of 0.5-1.5 mm as raw materials for subsequent reactions.
[0009] Step 3, Raw material mixing and catalyst addition: Mix the sieved hair particles with activated carbon particles at a mass ratio of 1:0.1-0.3 to form a mixed raw material; add 3%-8% of nickel-based catalyst by mass of the mixed raw material and stir thoroughly to ensure uniform dispersion of the catalyst;
[0010] Step 4, Anaerobic fermentation reaction: Transfer the mixed raw materials to an anaerobic fermenter, introduce nitrogen into the fermenter to remove the air inside, and make the oxygen content inside the fermenter less than 1%; adjust the temperature inside the fermenter to 35-45℃ and the pressure to 0.1-0.3MPa, and carry out the anaerobic fermentation reaction for 10-15 days;
[0011] Step 5, Methane Separation and Purification: After the fermentation reaction is completed, the gas generated in the fermenter is separated into methane gas by pressure swing adsorption using a gas separation device. The separated methane gas is then condensed in a condenser at -10 to 0℃ to remove the water content, resulting in methane gas with a purity of not less than 95%.
[0012] Preferably, the surfactant is sodium dodecylbenzenesulfonate or fatty alcohol polyoxyethylene ether.
[0013] Preferably, the drying equipment is a hot air circulating oven with an air velocity controlled at 0.5 - 1.5 m / s.
[0014] Preferably, the crusher is a hammer mill with a rotation speed of 1500-2000 r / min.
[0015] Preferably, the screening equipment is a vibrating screen with a vibration frequency of 20-30Hz.
[0016] Preferably, the nickel-based catalyst contains a nickel mass fraction of not less than 60%, and the catalyst surface is loaded with 5%-10% alumina as a co-catalyst.
[0017] Preferably, the anaerobic fermenter is a vertical cylindrical tank with an external insulation layer and an internal stirring device with a stirring speed of 10-20 r / min.
[0018] Preferably, the gas separation device includes multiple adsorption towers, each filled with a molecular sieve, which is either a 5A molecular sieve or a 13X molecular sieve.
[0019] Compared with existing technologies, the advantages of this invention are: (1) Abundant and environmentally friendly raw materials: This invention uses hair fragments as raw materials. Hair fragments are widely available and inexpensive. Converting them into methane realizes the resource utilization of waste, avoids the pollution of the environment caused by traditional treatment methods, and solves the problems of limited raw materials for existing methane production and environmental pollution caused by hair fragment treatment. (2) High conversion efficiency: Through hair pretreatment, crushing and sieving, the specific surface area of the hair is increased, providing good reaction conditions for microorganisms. At the same time, the addition of activated carbon and nickel-based catalysts further promotes the reaction, improves the conversion efficiency and yield of methane, and overcomes the problem of low conversion efficiency of existing biomass. (3) High product quality: The generated methane gas is separated and purified by pressure swing adsorption and condensation treatment, which can obtain methane gas with a purity of not less than 95%, meeting the requirements of different fields for methane purity and improving the market competitiveness of the product. (4) Strong process controllability: The present invention has precisely controlled the parameters of each process step, such as cleaning temperature and time, drying temperature and moisture content, crushing particle size, fermentation temperature and pressure, etc., which ensures the stability and repeatability of the process and facilitates large-scale industrial production. Detailed Implementation
[0020] Example 1
[0021] This embodiment provides a process for converting hair clippings into methane. The process for converting hair clippings into methane according to the present invention includes the following steps:
[0022] I. Hair Pretreatment: Place the collected hair fragments in a washing tank, add a surfactant solution with a mass fraction of 0.5% - 1%, and stir and wash at 30 - 40℃ for 15 - 30 minutes to remove grease and impurities from the hair surface. The surfactant reduces the surface tension of water, enhances the washing effect, and effectively removes grease and impurities from the hair, providing clean raw materials for subsequent processing. Then rinse with clean water until neutral, drain the water, and place in a drying device to dry at 60 - 80℃ until the moisture content is below 3%. Appropriate temperature and time ensure that the hair is thoroughly dried, avoiding the influence of moisture on subsequent reactions.
[0023] II. Hair Grinding and Sieving
[0024] The dried hair fragments are fed into a pulverizer and pulverized into powder with a particle size of less than 2 mm. Pulverization increases the specific surface area of the hair, which is beneficial for subsequent reactions. The pulverized hair powder is then sieved, selecting hair particles with a particle size of 0.5-1.5 mm as raw materials for the subsequent reactions. A suitable particle size range ensures the uniformity of the reactants and the efficiency of the reaction process.
[0025] III. Raw material mixing and catalyst addition
[0026] The sieved hair particles are mixed evenly with activated carbon particles at a mass ratio of 1:0.1-0.3 to form a mixed raw material. Activated carbon has a large specific surface area and good adsorption properties, providing a site for microorganisms to attach and promoting the reaction. 3%-8% (by mass) of a nickel-based catalyst is added to the mixed raw material and stirred thoroughly to ensure uniform dispersion. The nickel-based catalyst can lower the activation energy of the reaction, increasing the reaction rate and conversion efficiency.
[0027] IV. Anaerobic Fermentation: Transfer the mixed raw materials to an anaerobic fermenter. Introduce nitrogen gas into the fermenter to purge air, ensuring the oxygen content is below 1%. An anaerobic environment is essential for methane fermentation, guaranteeing the normal growth and metabolism of anaerobic microorganisms. Adjust the temperature inside the fermenter to 35-45℃ and the pressure to 0.1-0.3 MPa to initiate the anaerobic fermentation reaction for 10-15 days. Suitable temperature and pressure conditions provide a suitable growth environment for microorganisms, promoting methane production.
[0028] V. Methane Separation and Purification
[0029] After the fermentation reaction is complete, the gas produced in the fermenter is passed through a gas separation device, where methane gas is separated using pressure swing adsorption (PSA). PSA has advantages such as simple operation and high separation efficiency, and can effectively separate methane gas. The separated methane gas is then passed through a condenser and condensed at -10 to 0°C to remove moisture, yielding methane gas with a purity of not less than 95%. This condensation treatment further improves the purity of the methane, meeting the requirements of various applications.
[0030] Example 2
[0031] This embodiment provides a specific implementation of a process for converting hair fragments into methane. 10 kg of collected hair fragments are placed in a washing tank, and a 0.5% sodium dodecylbenzenesulfonate solution is added. The mixture is stirred and washed at 30°C for 15 minutes, then rinsed with water until neutral. After draining, the hair fragments are placed in a hot air circulating oven and dried at 60°C until the moisture content is 2%. The air velocity in the hot air circulating oven is controlled at 0.5 m / s.
[0032] The dried hair fragments were fed into a hammer mill at a speed of 1500 r / min and pulverized into powder with a particle size of less than 2 mm. The pulverized hair powder was then sieved through a vibrating screen at a vibration frequency of 20 Hz, and 8 kg of hair particles with a particle size of 0.5-1.5 mm were selected as raw materials for subsequent reactions.
[0033] 8 kg of sieved hair particles were mixed evenly with 0.8 kg of activated carbon particles to form a mixed raw material. 3% by mass of a nickel-based catalyst was added to the mixed raw material. The nickel-based catalyst contained 60% nickel by mass, and 5% by mass of alumina was loaded on the catalyst surface as a co-catalyst. The mixture was stirred thoroughly to ensure uniform dispersion of the catalyst.
[0034] The mixed raw materials were transferred to a vertical cylindrical anaerobic fermenter. The fermenter was equipped with an external insulation layer and an internal stirring device with a rotation speed of 10 r / min. Nitrogen gas was introduced into the fermenter to purge the air inside, bringing the oxygen content to 0.5%. The temperature inside the fermenter was adjusted to 35°C and the pressure to 0.1 MPa, and the anaerobic fermentation reaction was initiated for 10 days.
[0035] After the fermentation reaction is complete, the gas produced in the fermenter is passed through a gas separation device, which includes multiple adsorption towers filled with 5A molecular sieves. Methane gas is separated using pressure swing adsorption (PSA). The separated methane gas then passes through a condenser and is condensed at -10°C to remove moisture, yielding methane gas with a purity of 96%.
[0036] Example 3
[0037] This embodiment provides a specific implementation of a process for converting hair clippings into methane. 15 kg of collected hair clippings are placed in a washing tank, and a 1% (w / w) fatty alcohol polyoxyethylene ether solution is added. The mixture is stirred and washed at 40°C for 30 minutes, then rinsed with water until neutral. After draining, the hair clippings are placed in a hot air circulating oven and dried at 80°C until the moisture content is 1%. The air velocity in the hot air circulating oven is controlled at 1.5 m / s.
[0038] The dried hair fragments were fed into a hammer mill at a speed of 2000 r / min and pulverized into powder with a particle size of less than 2 mm. The pulverized hair powder was then sieved through a vibrating screen at a vibration frequency of 30 Hz, and 12 kg of hair particles with a particle size of 0.5-1.5 mm were selected as raw materials for subsequent reactions.
[0039] 12 kg of sieved hair particles were mixed evenly with 3.6 kg of activated carbon particles to form a mixed raw material. 8% nickel-based catalyst (70% nickel by mass) was added to the mixed raw material, and 10% alumina was loaded on the catalyst surface as a co-catalyst. The mixture was stirred thoroughly to ensure uniform dispersion of the catalyst.
[0040] The mixed raw materials were transferred to a vertical cylindrical anaerobic fermenter. The fermenter was equipped with an external insulation layer and an internal stirring device with a rotation speed of 20 r / min. Nitrogen gas was introduced into the fermenter to purge the air inside, bringing the oxygen content to 0.8%. The temperature inside the fermenter was adjusted to 45℃ and the pressure to 0.3 MPa, and the anaerobic fermentation reaction was initiated for 15 days.
[0041] After the fermentation reaction is complete, the gas produced in the fermenter is passed through a gas separation device, which includes multiple adsorption towers filled with 13X molecular sieves. Methane gas is separated using pressure swing adsorption (PSA). The separated methane gas then passes through a condenser and is condensed at 0°C to remove moisture, yielding methane gas with a purity of 97%.
[0042] In summary, the process for converting hair clippings into methane according to the present invention has high feasibility and practicality, and can effectively convert hair clippings into high-purity methane gas, thereby realizing the resource utilization of waste.
[0043] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A process for converting hair clippings into methane, characterized in that, Includes the following steps: Step 1, Hair Pretreatment: Place the collected hair fragments in a washing tank, add a surfactant solution with a mass fraction of 0.5% - 1%, and stir and wash at 30 - 40℃ for 15 - 30 minutes to remove oil and impurities from the hair surface; then rinse with clean water until neutral, drain the water, and place in a drying device to dry at 60 - 80℃ until the moisture content is below 3%; Step 2, Hair crushing and sieving: The dried hair fragments are fed into a crusher and crushed into powder with a particle size of less than 2 mm; then the crushed hair powder is sieved through a sieving device to select hair particles with a particle size of 0.5-1.5 mm as raw materials for subsequent reactions. Step 3, Raw material mixing and catalyst addition: Mix the sieved hair particles with activated carbon particles at a mass ratio of 1:0.1-0.3 to form a mixed raw material; add 3%-8% of the mass of the mixed raw material to the mixed raw material and stir thoroughly to ensure that the catalyst is evenly dispersed. Step 4, Anaerobic fermentation reaction: Transfer the mixed raw materials to an anaerobic fermenter, introduce nitrogen into the fermenter to remove the air inside, and make the oxygen content inside the fermenter less than 1%; adjust the temperature inside the fermenter to 35-45℃ and the pressure to 0.1-0.3MPa, and carry out the anaerobic fermentation reaction for 10-15 days; Step 5, Methane Separation and Purification: After the fermentation reaction is completed, the gas generated in the fermenter is separated into methane gas by pressure swing adsorption using a gas separation device. The separated methane gas is then condensed in a condenser at -10 to 0℃ to remove the water content, resulting in methane gas with a purity of not less than 95%.
2. The process for converting hair clippings into methane according to claim 1, characterized in that, The surfactant is sodium dodecylbenzenesulfonate or fatty alcohol polyoxyethylene ether.
3. The process for converting hair clippings into methane according to claim 1, characterized in that, The drying equipment is a hot air circulating oven with an air velocity controlled between 0.5 and 1.5 m / s.
4. The process for converting hair clippings into methane according to claim 1, characterized in that, The pulverizer is a hammer mill with a rotation speed of 1500-2000 r / min.
5. The process for converting hair clippings into methane according to claim 1, characterized in that, The screening equipment is a vibrating screen with a vibration frequency of 20-30Hz.
6. The process for converting hair clippings into methane according to claim 1, characterized in that, The nickel-based catalyst contains a nickel mass fraction of not less than 60%, and the catalyst surface is loaded with alumina with a mass fraction of 5%-10% as a co-catalyst.
7. The process for converting hair clippings into methane according to claim 1, characterized in that, The anaerobic fermenter is a vertical cylindrical tank with an external insulation layer and an internal stirring device with a rotation speed of 10-20 r / min.
8. The process for converting hair clippings into methane according to claim 1, characterized in that, The gas separation device includes multiple adsorption towers, each filled with a molecular sieve, which is either 5A or 13X molecular sieve.