System and method for producing pure hydrogen from coal

Abstract

The invention is a system for producing pure hydrogen (E) from coal (A), characterized by; at least one combustion unit (10) configured to heat and burn the mentioned coal (a), at least one water injection unit (20) configured to spray water onto carbon monoxide (b) gas released from the burned coal (a) to initiate a Water-Gas shift reaction and obtain a mixture of carbon dioxide and hydrogen (c), at least one palladium alloy membrane (30) configured to separate hydrogen (e) from the mentioned mixture of carbon dioxide and hydrogen (c) while retaining carbon dioxide (d), providing high-purity hydrogen (e) gas through its high hydrogen permeability and selectivity properties, at least one methanol production unit (40) configured to convert carbon dioxide (d) separated by the mentioned palladium alloy membrane (30) and part of the obtained hydrogen (e) gas into methanol (f).

Description

[0001] DESCRIPTION

[0002] SYSTEM AND METHOD FOR PRODUCING PURE HYDROGEN FROM COAL

[0003] Technical Field

[0004] The invention describes an innovative system and method focused on hydrogen production from carbon monoxide, a byproduct of coal combustion. By aiming to produce hydrogen efficiently and cleanly from fossil fuels, the invention represents a significant step forward in energy transformation and sustainable fuel technologies. Following hydrogen production, part of the hydrogen is used for methanol production, making this invention notable for its environmental sustainability and energy efficiency.

[0005] State of the Art

[0006] The process of heating coal in an oxygen-free (or inert) environment to enhance its carbon content is called carbonization or coking. When coal is heated in an airless environment, the organic groups within decompose into gases and condensates, separating as tar from the coal. The coking process involves the chemical transformation of coal by heating. During this process, water, gases, and other volatile substances within the coal are removed, and the carbon ratio increases. Coking can be performed at low temperatures (450-700°C) or high temperatures (900-1000°C). Before entering the coke oven, coal undergoes preparation steps such as crushing, breaking, and mixing. Low-temperature coking is used for lower-quality coals, while high-temperature coking is preferred for higher-quality coals.

[0007] The coking process is a method to enhance coal quality. However, it also has disadvantages. The coking process can result in the release of environmentally harmful gases, including carbon monoxide, sulfur dioxide, nitrogen oxides, and particulate matter. Moreover, due to the high temperatures required, the coking process increases energy consumption.

[0008] In current techniques, hydrogen production from coal is usually carried out via coal gasification or direct combustion. Gasification produces hydrogen-rich gases by reacting coal with air or oxygen under high temperatures and pressures. However, this process is associated with high energy consumption and environmental impacts, such as greenhouse gas emissions. Furthermore, purifying these gases and obtaining hydrogen in pure form require complex and costly processes. These challenges limit the wide applicability of hydrogen production and reduce environmental sustainability.

[0009] The energy efficiency of hydrogen production from coal is generally low, which increases production costs. Gasification processes often require desulfurization and the removal of other contaminants, adding additional steps and costs. Additionally, managing solid and liquid waste generated from these processes poses environmental and operational challenges.

[0010] Membranes used in current techniques are typically metallic or polymer-based and are widely used in hydrogen purification processes. However, these membranes also have disadvantages. While metallic membranes are effective at high temperatures, they are costly and susceptible to wear. Polymer-based membranes operate at lower temperatures but generally have lower hydrogen selectivity and permeability. Both types of membranes may experience efficiency losses over time in gas purification processes. Additionally, these membranes face stability issues in aggressive chemical environments and high-temperature conditions, shortening their lifespan and requiring frequent replacement or maintenance, which increases operational costs. The effectiveness of such membranes in hydrogen production is limited, and they typically require energy- intensive processes, reducing the overall efficiency of hydrogen production. Thus, developing more durable, cost-effective, and efficient membrane technologies is of great importance.

[0011] These disadvantages underscore the need for more environmentally friendly and sustainable methods of hydrogen production from coal and necessitate the development of alternative technologies.

[0012] Objective of the Invention

[0013] The primary objective of the invention is to produce hydrogen from carbon monoxide obtained from coal using a more efficient and environmentally friendly method. This contributes to sustainable energy production by reducing energy consumption and minimizing carbon emissions. Another objective of the invention is to distinguish hydrogen production from coal through the use of a palladium alloy membrane. This membrane stands out with its high hydrogen permeability and selectivity, enabling the separation of hydrogen in a purer form and reducing by-products. Compared to conventional purification methods, the palladium alloy membrane offers a more effective and energy-efficient alternative, improving the overall process efficiency and reducing environmental impacts. This innovation represents a significant step forward in coal-based hydrogen production technologies.

[0014] A further objective of the invention is to reduce the cost of the coal gasification process and enhance the widespread applicability of this technology.

[0015] Another objective of the invention is to utilize carbon dioxide, which is generated during hydrogen production, as an added value in methanol production. This approach ensures the reuse of waste gases, making waste management more efficient and providing economic benefits.

[0016] Another objective of the invention is to make hydrogen production from coal more environmentally friendly and sustainable, aiming to play a significant role in the transformation of fossil fuels into clean energy.

[0017] An additional objective of the invention is to enhance the overall efficiency and safety of the process, contributing to the development of coal-based hydrogen production technologies. This innovative approach seeks to make industrial-scale hydrogen production more environmentally friendly, economical, and sustainable, offering an innovative perspective to the energy sector. By overcoming the challenges of transforming fossil fuels into clean energy, the invention provides a new perspective on energy transition.

[0018] To achieve the above objectives, the invention is a system for producing pure hydrogen from coal, comprising; at least one combustion unit configured to heat and burn the mentioned coal, at least one water injection unit configured to spray water onto carbon monoxide gas released from the burned coal to initiate a Water-Gas shift reaction and obtain a mixture of carbon dioxide and hydrogen, at least one palladium alloy membrane configured to separate hydrogen from the mentioned mixture of carbon dioxide and hydrogen while retaining carbon dioxide, providing high-purity hydrogen gas through its high hydrogen permeability and selectivity properties, at least one methanol production unit configured to use part of the hydrogen gas obtained and the carbon dioxide separated by the palladium alloy membrane to produce methanol.

[0019] Explanation of Figures

[0020] Figure- 1 represents the system for producing pure hydrogen from coal as described in the invention.

[0021] Explanation of Part References

[0022] A. Coal

[0023] B. Carbon monoxide

[0024] C. Mixture of carbon dioxide and hydrogen

[0025] D. Carbon dioxide

[0026] E. Hydrogen

[0027] F. Methanol

[0028] 10. Combustion Unit

[0029] 20. Water Injection Unit

[0030] 30. Palladium-Alloy Membrane

[0031] 40. Methanol Production Unit

[0032] Detailed Description of the Invention

[0033] Referring to Figure 1 , in the system for producing pure hydrogen (E) from coal (A), the coal (A) is heated and burned using a combustion unit (10). As a result of burning the coal (A), carbon monoxide (B) gas is released. Water is sprayed onto the mentioned carbon monoxide (B) gas using a water injection unit (20), initiating a Water-Gas shift reaction, and as a result, a mixture of carbon dioxide and hydrogen (C) is obtained. Subsequently, the mentioned gas mixture (C) is passed through a palladium alloy membrane (30). The palladium alloy membrane (30) allows hydrogen (E) in the gas mixture (C) to pass through while retaining carbon dioxide (D). Due to the high hydrogen permeability and selectivity properties of the palladium alloy membrane (30), high-purity hydrogen (E) gas is obtained. A portion of the obtained hydrogen (E) gas — preferably between 3% and 13% — and the carbon dioxide (D) separated by the palladium alloy membrane (30) are converted into methanol (F) using a methanol production unit (40). Thus, the invention ensures the reuse of waste gases, making waste management more efficient and providing economic benefits.

[0034] At the core of this process lies the Water-Gas shift reaction, which can be formulated as follows:

[0035] CO(g) + H2O (vapor) CO2(g) + H2(g)

[0036] This reaction occurs at a temperature range of 150-450°C and releases a small amount of energy, approximately 41 .1 kJ (10 kcal) per mole, making it mildly exothermic. During this process, carbon monoxide (B) and water vapor transform into carbon dioxide (D) and hydrogen (E) gases, which is of great industrial importance.

[0037] With the use of the palladium alloy membrane (30), the hydrogen (E) obtained from the mentioned Water-Gas shift reaction is separated at high purity without consuming energy. The palladium alloy membrane (30) allows hydrogen (E) to pass through while retaining carbon dioxide (D), ensuring a highly selective separation process.

[0038] In methanol (F) production, carbon dioxide (D) and hydrogen (E) gases react at high temperatures of 230-255°C to produce methanol (F). This process begins by increasing the pressure of carbon dioxide (D) and hydrogen (E) to 300-330 bar and feeding them into a reactor, resulting in methanol (F) with high efficiency and purity.

[0039] Overall, this process aims to reuse waste gases from the mining sector, thereby reducing environmental impacts and increasing economic benefits. This approach seeks to establish a sustainable industrial model by converting waste gases into valuable chemical products, thus creating both environmental and economic value.

[0040] The steps of the process used in the system for producing pure hydrogen (E) from coal (A) are as follows:

[0041] A) Heating and burning the coal (A) using a combustion unit (10); B) Spraying water onto the carbon monoxide (B) gas released from the burned coal (A) using at least one water injection unit (20) to initiate a Water-Gas shift reaction and produce a mixture of carbon dioxide and hydrogen (C), C) Passing the hydrogen (E) from the mentioned mixture of carbon dioxide and hydrogen (C) through at least one palladium alloy membrane (30) with high hydrogen permeability and selectivity properties to obtain high-purity hydrogen (E) gas while retaining carbon dioxide (D), D) Using the carbon dioxide (D) separated by the palladium alloy membrane (30) and a portion of the obtained hydrogen (E) gas to produce methanol (F) through a methanol production unit (40).

Claims

CLAIMS1. The invention is a system for producing pure hydrogen (E) from coal (A), characterized by; at least one combustion unit (10) configured to heat and burn the mentioned coal (a), at least one water injection unit (20) configured to spray water onto carbon monoxide (b) gas released from the burned coal (a) to initiate a Water- Gas shift reaction and obtain a mixture of carbon dioxide and hydrogen (c), at least one palladium alloy membrane (30) configured to separate hydrogen (e) from the mentioned mixture of carbon dioxide and hydrogen (c) while retaining carbon dioxide (d), providing high-purity hydrogen (e) gas through its high hydrogen permeability and selectivity properties, at least one methanol production unit (40) configured to convert carbon dioxide (d) separated by the mentioned palladium alloy membrane (30) and part of the obtained hydrogen (e) gas into methanol (f).

2. The system for producing pure hydrogen (E) from coal (A) according to claim 1 , characterized in that the methanol production unit (40) is configured to operate at high temperatures between 230-255°C and pressure ranges of 300-330 bar to convert carbon dioxide (D) and hydrogen (E) gases into methanol (F).

3. The system for producing pure hydrogen (E) from coal (A) according to claim 1 , characterized in that the water injection unit (20) is configured to initiate the Water- Gas shift reaction at a temperature range of 150-450°C.

4. The system for producing pure hydrogen (E) from coal (A) according to claim 1 , characterized in that the amount of hydrogen (E) used in methanol production by the methanol production unit (40) ranges between 3% and 13% of the total hydrogen (E) produced by the system.

5. The system for producing pure hydrogen (E) from coal (A) according to claims 1 and 3, characterized in that the Water-Gas shift reaction initiated by the water injection unit (20) is configured to occur exothermically, releasing 41.1 kJ (10 kcal) of energy per mole.

6. A method for producing pure hydrogen (E) from coal (A), comprising: at least one combustion unit (10) configured to heat and burn the mentioned coal (a),• at least one water injection unit (20) configured to spray water onto carbon monoxide (b) gas released from the burned coal (a) to initiate a Water-Gas shift reaction and obtain a mixture of carbon dioxide and hydrogen (c),• at least one palladium alloy membrane (30) configured to separate hydrogen (e) from the mentioned mixture of carbon dioxide and hydrogen (c) while retaining carbon dioxide (d), providing high-purity hydrogen (e) gas through its high hydrogen permeability and selectivity properties,• at least one methanol production unit (40) configured to convert carbon dioxide (d) separated by the mentioned palladium alloy membrane (30) and part of the obtained hydrogen (e) gas into methanol (f),• characterized by the process steps of:• heating and burning the coal (a) using a combustion unit (10),• spraying water onto the carbon monoxide (b) gas released from the burned coal (a) using at least one water injection unit (20) to initiate a Water-Gas shift reaction and produce a mixture of carbon dioxide and hydrogen (c),• passing hydrogen (e) from the mentioned mixture of carbon dioxide and hydrogen (c) through at least one palladium alloy membrane (30) with high hydrogen permeability and selectivity properties to obtain high-purity hydrogen (e) gas while retaining carbon dioxide (d),• using the carbon dioxide (d) separated by the palladium alloy membrane (30) and part of the obtained hydrogen (e) gas to produce methanol (f) through a methanol production unit (40).

7. The method for producing pure hydrogen (E) from coal (A) according to claim 6, characterized in that the process step of initiating the Water-Gas shift reaction by spraying water onto the carbon monoxide (B) gas released from the burned coal (A) is carried out at a temperature range of 150-450°C.

8. The method for producing pure hydrogen (E) from coal (A) according to claim 6, characterized in that the process step of producing methanol (F) through a methanol production unit (40) is carried out at high temperatures between 230-255°C and pressure ranges of 300-330 bar.

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