System and method for obtaining pure hydrogen and methanol from natural gas

Abstract

A system for obtaining pure hydrogen (F) and methanol (G) from natural gas for use in the energy sector, characterized by; a first water injection unit (10) that performs the process of injecting water into methane gas (A), the main component of natural gas, at high temperatures, initiating the first steam methane reforming process and resulting in the production of a gas mixture containing 3H₂ + CO (B), a second water injection unit (20) that performs a second water injection process at a temperature lower than that of the first water injection unit (10) on the 3H₂ + CO (B) gas mixture obtained at the outlet of the first water injection unit (10), initiating the Water-Gas shift reaction and producing a gas mixture containing 4H₂ + CO₂ (C), at least one palladium alloy membrane (30) that receives the gas mixture of 4H₂ + CO₂ (C) obtained at the outlet of the second water injection unit (20), allowing only hydrogen (F) to pass through while separating other gases as 4H₂ (E) and carbon dioxide (D), thereby ensuring the production of high-purity hydrogen (F), at least one methanol production unit (40) designed to utilize the carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the 4H₂ (E) gas to produce methanol (G).

Description

[0001] SYSTEM AND METHOD FOR OBTAINING PURE HYDROGEN AND METHANOL FROM NATURAL GAS

[0002] Technical Field

[0003] The invention relates to an integrated system and method for obtaining pure hydrogen and methanol, aimed at improving natural gas steam reforming processes as an alternative to energy-intensive traditional methods, utilizing a palladium alloy membrane to separate hydrogen from other gases without energy consumption and transferring the resulting CO2 emissions to the methanol production process for reuse in the energy sector.

[0004] Additionally, the invention’s potential integration with renewable energy sources plays a significant role in making the energy sector more sustainable and environmentally friendly. Pure hydrogen production is considered a critical component for the development and application of clean energy technologies, such as fuel cells. Furthermore, this process reduces the challenges associated with the storage and transportation of hydrogen, thereby contributing to the expansion of the hydrogen economy and the decarbonization of energy systems. The economic and operational efficiency of this technology enhances its industrial-scale applicability, while its ability to reduce the carbon footprint is crucial for combating climate change. Consequently, the invention represents a transformative step in the energy sector and environmental sustainability.

[0005] State of The Art

[0006] Natural gas, particularly methane, stands out as a valuable raw material for hydrogen production in a world where the demand for clean and efficient energy sources is growing. Existing methods used to obtain hydrogen from methane gas address the sustainability and efficiency challenges faced in the energy sector but also present several disadvantages. These methods and their shortcomings are as follows: Steam Methane Reforming (SMR): Steam methane reforming, a key process for industrial hydrogen production, involves reacting methane with steam at high temperatures to produce hydrogen and carbon monoxide. However, this process leads to high operating costs due to its energy-intensive nature and requires large-scale facilities, increasing the initial investment cost. Furthermore, SMR generates carbon dioxide emissions, which is a significant drawback in terms of environmental sustainability. (CH4 + H2O CO + 3H2)

[0007] Partial Oxidation of Methane: This method produces hydrogen through controlled combustion of methane at high temperatures, increasing energy consumption and operating costs. The process, which requires controlled combustion, generates harmful by-products, and the complexity of reactor design brings operational and financial burdens. (CH4 + 1 / 2 02 CO + 2H2)

[0008] Autothermal Reforming (ATR): A combination of SMR and partial oxidation, autothermal reforming reacts methane with oxygen and steam, performing both exothermic and endothermic reactions. While this complex process requires high initial investments and precise control systems to maintain stability, it still produces significant greenhouse gas emissions, though less than SMR. (CH4 + x / 2 02 + (1-x)H20 CO + (3-x)H2)

[0009] Metal-Organic Frameworks (MOFs) and Membrane Technologies: MOFs and membrane technologies used for separating hydrogen from methane-containing gas mixtures have the potential to operate at lower temperatures. However, the industrialscale durability and performance of these materials remain uncertain. Additionally, high production costs, material stability issues, and unproven scalability processes present challenges for commercial use.

[0010] Each of these methods offers advantages while also requiring improvement in terms of energy efficiency, environmental impact, and economic feasibility.

[0011] Emission Challenges in Hydrogen Production

[0012] During the process of hydrogen production from methane gas, several types of harmful gases are typically produced. The primary by-products are carbon monoxide (CO) and carbon dioxide (C02). Additionally, small amounts of other pollutant gases, such as nitrogen oxides (NOx) and sulfur oxides (SOx), can also be generated during the process. These gases are described as follows;

[0013] Carbon Monoxide (CO): CO is produced as a by-product during processes such as steam methane reforming (SMR) and partial oxidation of methane. CO is not only hazardous to human health but also contributes to the greenhouse effect. However, CO is often converted into hydrogen through a Water-Gas shift reaction to mitigate its harmful impact.

[0014] Carbon Dioxide (CO2): CO2 is released during steam methane reforming and the Water- Gas shift reaction, contributing to global warming due to its greenhouse gas effects. Reducing CO2 emissions is a significant aspect of making hydrogen production more environmentally friendly.

[0015] Nitrogen Oxides (NOx): NOx gases form when nitrogen and oxygen in the air and fuel react during high-temperature combustion processes. These gases contribute to acid rain and ozone layer depletion.

[0016] Sulfur Oxides (SOx): SOx gases are formed particularly during the combustion of sulfur- containing fuels. These gases contribute to acid rain and have adverse effects on human health.

[0017] Various purification and treatment technologies have been developed to reduce the emissions of these harmful by-products. For example, carbon capture and storage (CCS) technologies are used to capture CO2 before it is released into the atmosphere and store it underground. For NOx and SOx emissions, technologies such as selective catalytic reduction (SCR) and flue gas desulfurization (FGD) are employed. These treatment methods are crucial for ensuring compliance with environmental regulations and achieving a cleaner environment.

[0018] Producing high-purity hydrogen typically requires energy-intensive processes like pressure swing adsorption (PSA). In hydrogen production from natural gas via the steam methane reforming process, capturing carbon dioxide adds approximately 25-30% to the cost of the hydrogen produced, with 80-85% of the captured CO2 being accounted for. Additionally, the disposal of separated CO2 gas introduces an extra production cost. Generally, the efficiency of steam methane reforming systems ranges between 65% and 75%.

[0019] In conclusion, the invention integrates the processes of hydrogen production from methane, the primary component of natural gas, and the conversion of waste carbon dioxide gas into methanol. This process aims to reduce the carbon footprint in both the energy sector and the chemical industry while providing economic benefits through the production of methanol, a valuable chemical. By overcoming the environmental and economic disadvantages of traditional methods, this invention represents a significant step forward in sustainable energy production and the fight against climate change. This technology can play a critical role in the global transition to clean energy sources and the reduction of carbon emissions, thus making an important contribution toward a greener future.

[0020] Objectives Of The Invention

[0021] The primary objective of the invention is to produce pure hydrogen from natural gas, specifically methane, by reducing energy intensity and enhancing efficiency. This process aims to provide an alternative to conventional methods that require high temperatures, ensuring hydrogen production is both efficient and environmentally friendly.

[0022] Another objective of the invention is to minimize energy consumption by developing a more environmentally friendly and sustainable hydrogen production process. This process involves the effective separation of hydrogen from other gases using palladium alloy membranes, offering a less energy-intensive and more efficient method.

[0023] Another objective of the invention is to significantly reduce CO2 emissions. This is achieved by converting carbon dioxide, a by-product of hydrogen production, into methanol, a valuable chemical. This approach aims to mitigate the environmental impacts of fossil fuel usage.

[0024] Another objective of the invention is to facilitate integration with renewable energy sources, thereby improving the overall sustainability and environmental profile of energy systems. This goal promotes the use of pure hydrogen, especially in clean energy technologies such as fuel cells supported by renewable energy sources.

[0025] Another objective of the invention is to address the existing challenges associated with the storage and transportation of hydrogen. This approach will help expand the hydrogen economy and contribute to a broader decarbonization of energy systems.

[0026] Another objective of the invention is to encourage transformation within the energy sector and provide innovative solutions in the field of environmental sustainability. This particularly emphasizes strategies aimed at reducing the carbon footprint of energy production and chemical manufacturing processes.

[0027] Another objective of the invention is to enhance industrial-scale applicability and ensure a reduction in CO2 emissions. This goal involves achieving the necessary technological advancements for sustainable energy production while considering both economic and operational efficiency.

[0028] Another objective of the invention is to play a critical role in combating climate change by reducing carbon emissions. This approach aims to support the global transition to clean energy sources and make a significant contribution toward a greener future.

[0029] Another objective of the invention is to overcome the limitations of existing hydrogen production technologies and provide advanced solutions in terms of energy efficiency, environmental impact, and economic feasibility. This approach aims to address challenges in the industry with innovative and effective solutions, shaping the future of energy production.

[0030] Explanation of the Figures

[0031] Figure- 1 provides a representative view of the system for obtaining pure hydrogen and methanol from natural gas, which is the subject of the invention.

[0032] Explanation of Part References

[0033] 10. First Water Injection Unit C. 4H2+CO2 20. Second Water Injection Unit D. Carbon Dioxide

[0034] 30. Palladium Alloy Membrane E. 4H2

[0035] 40. Methanol Production Unit F. Hydrogen

[0036] A. Methane H. 3H2

[0037] B. 3H2+CO G. Methanol

[0038] Detailed Description Of The Invention

[0039] Referring to Figure 1 , the system for obtaining pure hydrogen and methanol (G) from natural gas, which is the subject of the invention, includes; a first water injection unit (10) that performs the process of injecting water into methane gas (A), the primary component of natural gas, at high temperatures, initiating the first steam methane reforming process and resulting in the production of a gas mixture containing 3H2+ CO (B), a second water injection unit (20) that performs a second water injection process at a temperature lower than that of the first water injection unit (10) on the 3H2+ CO (B) gas mixture obtained at the outlet of the first water injection unit (10). This initiates the second Water-Gas shift reaction and produces a gas mixture containing 4H2+ CO2(C), at least one palladium alloy membrane (30) that receives the gas mixture of 4H2+ CO2(C) obtained at the outlet of the second water injection unit (20), allowing only hydrogen (F) to pass through while separating other gases as 4H2(E) and carbon dioxide (D), thereby ensuring the production of high-purity hydrogen (F), at least one methanol production unit (40) designed to utilize the carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the 4H2(E) gas to produce methanol (G).

[0040] Since 3H2(H) of the 4H2(E) gas is used for methanol production, pure hydrogen (F) gas can be obtained at the system’s output.

[0041] Operating Principle of the Invention:

[0042] The system begins with methane gas (A), the primary component of natural gas. When methane (A) enters the first water injection unit (10), the steam methane reforming process occurs at high temperatures (approximately 1000°C), producing hydrogen (F) gas and a gas mixture containing carbon monoxide, represented as 3H2+ CO (B). The gas mixture of 3H2+ CO (B) is then directed to the second water injection unit (20). Here, an additional reforming process is performed at a lower temperature (approximately 400°C), increasing hydrogen production efficiency and producing a gas mixture enriched with carbon dioxide, represented as 4H2+ CO2(C).

[0043] The 4H2+ CO2(C) gas mixture produced is then passed through the palladium alloy membrane (30). This membrane allows hydrogen (F) molecules to pass through while retaining larger gas molecules such as carbon monoxide and carbon dioxide (D), thereby isolating pure hydrogen (F).

[0044] The obtained pure hydrogen (E) can be used for energy production or storage. The system also separates by-products like carbon dioxide (D). This carbon dioxide (D) is directed to the methanol production unit (40), where it reacts with additional hydrogen (F) through a chemical process to form methanol (G). This transformation converts carbon dioxide (D), a by-product, into methanol (G), a valuable chemical, reducing potential environmental impacts.

[0045] Process Steps of the Method Used in the Invention:

[0046] A. Methane gas (A) taken from the system input is injected with water at high temperatures through the first water injection unit (10), initiating the first steam methane reforming process and resulting in the production of a gas mixture containing hydrogen gas (F) and carbon monoxide, represented as 3H2+ CO (B).

[0047] B. The obtained gas mixture of 3H2+ CO (B) is injected with water at high temperatures through the second water injection unit (20), initiating the Water-Gas shift reaction and resulting in a gas mixture with a higher hydrogen content, represented as 4H2+ CO2(C).

[0048] C. The gas mixture of 4H2+ CO2(C) obtained at the outlet of the second water injection unit (20) is passed through at least one palladium alloy membrane (30). This membrane separates the 4H2+ CO2(C) gas mixture into 4H2(E) and carbon dioxide (D), ensuring the production of pure hydrogen (F). D. The carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the 4H2(E) gas are used in the methanol production unit (40) to produce methanol (G). This process reduces energy intensity and increases efficiency, offering a more sustainable and environmentally friendly hydrogen production method compared to traditional techniques. Furthermore, the use of the palladium alloy membrane (30) minimizes energy consumption and significantly reduces carbon dioxide (D) emissions. This technology promotes transformation in the energy sector and provides innovative solutions in the field of environmental sustainability, thereby contributing to the decarbonization of energy systems.

Claims

CLAIMS1. A system for obtaining pure hydrogen (F) and methanol (G) from natural gas for use in the energy sector, characterized by:• a first water injection unit (10) that performs the process of injecting water into methane gas (A), the main component of natural gas, at high temperatures, initiating the first steam methane reforming process and resulting in the production of a gas mixture containing 3H2+ CO (B),• a second water injection unit (20) that performs a second water injection process at a temperature lower than that of the first water injection unit (10) on the 3H2+ CO (B) gas mixture obtained at the outlet of the first water injection unit (10), initiating the Water-Gas shift reaction and producing a gas mixture containing 4H2+ CO2(C),• at least one palladium alloy membrane (30) that receives the gas mixture of 4H2+ CO2(C) obtained at the outlet of the second water injection unit (20), allowing only hydrogen (F) to pass through while separating other gases as 4H2(E) and carbon dioxide (D), thereby ensuring the production of high-purity hydrogen (F),• at least one methanol production unit (40) designed to utilize the carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the 4H2(E) gas to produce methanol (G).

2. A system for obtaining pure hydrogen (F) and methanol (G) from natural gas according to claim 1, characterized by the water injected by the first water injection unit (10) being at a temperature of 1000°C.

3. A system for obtaining pure hydrogen (F) and methanol (G) from natural gas according to claim 1 , characterized by the water injected by the second water injection unit (20) being at a temperature of 400°C.

4. A method for obtaining pure hydrogen (F) and methanol (G) from natural gas for use in the energy sector, characterized by: a first water injection unit (10) that performs the process of injecting water into methane gas (A), the main component of natural gas, at high temperatures,initiating the first steam methane reforming process and resulting in the production of a gas mixture containing 3H2+ CO (B),• a second water injection unit (20) that performs a second water injection process at a temperature lower than that of the first water injection unit (10) on the 3H2+ CO (B) gas mixture obtained at the outlet of the first water injection unit (10), initiating the Water-Gas shift reaction and producing a gas mixture containing 4H2+ CO2(C),• at least one palladium alloy membrane (30) that receives the gas mixture of 4H2+ CO2(C) obtained at the outlet of the second water injection unit (20), allowing only hydrogen (F) to pass through while separating other gases as 4H2(E) and carbon dioxide (D), thereby ensuring the production of high-purity hydrogen (F),• at least one methanol production unit (40) designed to utilize the carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the 4H2(E) gas to produce methanol (G); where the process steps are characterized by:• Methane gas (A) taken from the system input being injected with water at high temperatures through the first water injection unit (10), initiating the first steam methane reforming process and resulting in the production of a gas mixture containing hydrogen gas (F) and carbon monoxide, represented as 3H2+ CO (B),• The obtained gas mixture of 3H2+ CO (B) being injected with water at high temperatures through the second water injection unit (20), initiating the water- gas shift reaction and resulting in a gas mixture with a higher hydrogen content, represented as 4H2+ CO2(C),The gas mixture of 4H2+ CO2(C) obtained at the outlet of the second water injection unit (20) being passed through at least one palladium alloymembrane (30), which separates the gas mixture into 4H2(E) and carbon dioxide (D), thereby ensuring the production of pure hydrogen (F),• The carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the 4H2(E) gas being used in the methanol production unit (40) to produce methanol (G).

5. A method for obtaining pure hydrogen (F) and methanol (G) from natural gas according to claim 4, characterized by the first water injection unit (10) performing water injection at a temperature of 1000°C.

6. A method for obtaining pure hydrogen (F) and methanol (G) from natural gas according to claim 4, characterized by the second water injection unit (20) performing water injection at a temperature of 400°C.

Images