CN113526460B - A device and method for pyrolyzing organic solid waste to extract hydrogen - Google Patents

Abstract

The invention discloses a device for extracting hydrogen from pyrolysis organic solid waste, which comprises a pyrolysis unit, a combustion chamber and a hydrogen purification unit, wherein the combustion chamber and the hydrogen purification unit are respectively communicated with the pyrolysis unit, a first valve is arranged between the pyrolysis unit and the combustion chamber, and a second valve is arranged between the pyrolysis unit and the hydrogen purification unit; the pyrolysis unit is used for pyrolyzing organic solid-phase garbage, gas generated by pyrolysis can enter the combustion chamber to carry out secondary combustion, waste heat generated by secondary combustion is used for supplying heat to the pyrolysis unit, the hydrogen purification unit is used for purifying the pyrolysis gas by hydrogen, and a gas supply channel is further arranged between the hydrogen purification unit and the combustion chamber and used for returning purified gas to the combustion chamber. The invention also provides a method for extracting hydrogen from the pyrolysis organic solid waste. The invention can effectively improve the hydrogen yield, save energy, reduce energy consumption and has good economic benefit.

Description

A device and method for pyrolyzing organic solid waste to extract hydrogen

Technical field

The invention relates to the technical field of hydrogen extraction, and in particular to a device and method for pyrolyzing organic solid waste to extract hydrogen.

Background technique

As a clean energy source, hydrogen has been widely used in various fields. Traditional hydrogen production methods: such as electrolysis, hydrocarbon cracking, hydrocarbon steam reforming, and refinery gas extraction, can all produce hydrogen with higher purity. , but these methods consume high power and are less economical.

Contents of the invention

The purpose of the present invention is to provide a device for pyrolyzing organic solid waste to extract hydrogen, which can increase hydrogen production, save energy, reduce energy consumption, and have good economic benefits.

In order to solve the above technical problems, the present invention provides a device for pyrolyzing organic solid waste to extract hydrogen, including a pyrolysis unit, a combustion chamber and a hydrogen purification unit respectively connected with the pyrolysis unit, and the pyrolysis unit is connected with the hydrogen purification unit. A first valve is provided between the combustion chambers, and a second valve is provided between the hydrogen purification unit;

The pyrolysis unit is used to pyrolyze organic solid waste. The gas generated by pyrolysis can enter the combustion chamber for secondary combustion, and the waste heat generated by the secondary combustion is used to provide heat for the pyrolysis unit. The hydrogen purification unit is used to purify hydrogen from the pyrolysis gas, and a gas supply channel is provided between the hydrogen purification unit and the combustion chamber for the purified gas to return to the combustion chamber.

The working process of extracting hydrogen according to the present invention is as follows:

First, control the initial pyrolysis temperature in the pyrolysis unit between 200 and 400°C, and perform low-temperature pyrolysis of the organic solid waste. At this time, the hydrogen content in the pyrolysis gas is low, only about 5%. If Extraction of hydrogen at this time is less economical; therefore, the second valve is controlled to open and the first valve is closed, and the pyrolysis gas enters the combustion chamber for secondary combustion, and the waste heat generated will continue to provide heat for the pyrolysis unit. When the temperature in the pyrolysis unit reaches above 800°C and the hydrogen content in the pyrolysis gas is high, the first valve can be controlled to open and the second valve to close. The pyrolysis gas enters the hydrogen purification unit for purification, and the remaining gas is returned to combustion. The chamber continues to burn and continuously supplies heat to the pyrolysis unit to ensure that the temperature in the pyrolysis unit is maintained above 800°C and to ensure the production of hydrogen.

In this way, the present invention first performs low-temperature pyrolysis of organic solid waste, and allows the pyrolysis gas to enter the combustion chamber for secondary combustion, and fully utilizes the waste heat generated by the secondary combustion to heat the pyrolysis unit, so that the pyrolysis temperature reaches The preset temperature not only realizes the recycling of waste heat, increases the production of hydrogen, but also saves energy and reduces energy consumption, which has good economic benefits.

Optionally, the pyrolysis unit is a low-temperature magnetization pyrolysis furnace, and the initial temperature in the low-temperature magnetization pyrolysis furnace is 200 to 400°C;

Or, the temperature in the combustion chamber is above 1100°C.

Optionally, the combustion chamber is provided with an exhaust gas outlet channel, and a heat supply pipe is provided inside the pyrolysis unit and communicates with the exhaust gas outlet channel.

Optionally, it also includes a temperature detection unit disposed in the pyrolysis unit, and a controller, the temperature detection unit is used to monitor the pyrolysis temperature, the temperature detection unit, the first valve, the The second valves are all electrically connected to the controller, and the controller can control the opening and closing of the first valve and the second valve according to the monitoring results of the temperature detection unit.

Optionally, the hydrogen purification unit includes a membrane separation device and a pressure swing adsorption device connected in sequence, and the membrane separation device includes at least two stages of membrane separators.

Optionally, it also includes a first compressor and a buffer tank connected in sequence, the pyrolysis gas is compressed by the first compressor and stored in the buffer tank, and the outlet of the buffer tank is separated from the membrane. device connection.

Optionally, a second compressor and a gas storage tank are connected in sequence. The hydrogen purified by the pressure swing adsorption device is pressurized by the second compressor and then stored in the gas storage tank.

Optionally, a post-processing unit communicated with the combustion chamber is also included for post-processing the exhaust gas generated after combustion and discharging it after reaching the standard.

The invention also provides a method for pyrolyzing organic solid waste to extract hydrogen. Based on the device for pyrolyzing organic solid waste to extract hydrogen according to any one of claims 1 to 8, the invention includes the following steps:

The pyrolysis unit is controlled to have an initial temperature, the first valve is opened, and the second valve is closed. The pyrolysis unit pyrolyzes the organic solid waste, and the generated pyrolysis gas enters the combustion chamber for secondary combustion, and the secondary combustion produces The waste heat provides heat for the pyrolysis unit;

When the pyrolysis temperature in the pyrolysis unit reaches the preset temperature, the first valve is controlled to close, the second valve is opened, the generated pyrolysis gas enters the hydrogen purification unit for hydrogen purification, and the remaining gas returns to The combustion chamber continues to burn and continues to provide heat to the pyrolysis unit so that the pyrolysis temperature remains above the preset temperature.

The method for extracting hydrogen from pyrolyzing organic solid waste of the present invention is applicable to the aforementioned device for extracting hydrogen from pyrolyzing organic solid waste. Therefore, it has the same technical effect as the aforementioned device for extracting hydrogen from pyrolyzing organic solid waste, and will not be described again here.

Optionally, the initial temperature is 200-400°C, and the preset temperature is 800°C.

Description of the drawings

Figure 1 is a schematic flow chart of a specific embodiment of a device for pyrolyzing organic solid waste to extract hydrogen provided by the present invention;

Figure 2 is a schematic structural diagram of the hydrogen purification unit in the device for pyrolyzing organic solid waste to extract hydrogen in Figure 1;

Figure 3 is a schematic flow chart of the hydrogen purification unit of Figure 2;

Among them, the reference numbers in Figures 1 to 3 are explained as follows:

1-low temperature magnetization pyrolysis furnace; 2-combustion chamber; 3-hydrogen purification unit; 31-buffer tank; 32-membrane separation device; 33-first compressor; 34-pressure swing adsorption device; 35-gas storage tank; 4-Post-processing unit.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Before introducing the specific solutions of the present invention, the technical ideas are first described.

According to engineering practice, we can know that a large amount of combustible gases, such as hydrogen, carbon monoxide, methane, etc., will be produced during the pyrolysis of organic solid waste. Therefore, if the hydrogen in the pyrolysis gas can be extracted and utilized as a resource, it can produce good economic and environmental benefits without causing a waste of resources.

According to research, as the pyrolysis temperature increases, the hydrogen content in the pyrolysis gas will gradually increase. The "Industrial Solid Waste Treatment Technology" published by Sinopec Press gives the effect of pyrolysis temperature on the gas composition and content. Relevant data are as shown in the table below.

Effect of pyrolysis temperature on gas composition (%)

As can be seen from the above table, when the pyrolysis temperature reaches 815°C, the proportion of hydrogen is as high as about 27.6%, and the production of hydrogen will be greatly increased. However, if high-temperature pyrolysis above 800°C is directly used for organic solid waste, the energy consumption will be high, and the equipment It is complicated, will cause a lot of energy waste, and the economic benefits will not be high.

The present invention is designed based on this technical idea, and the specific solution of the present invention is introduced in detail below.

The words "first", "second" and other words used in this article are only for the convenience of describing two or more structures or components with the same or similar structure and/or function, and do not indicate the order and/or importance. Some kind of special limitation.

Please refer to FIG. 1 , which is a schematic flow chart of a specific embodiment of a device for pyrolyzing organic solid waste to extract hydrogen provided by the present invention.

The invention provides a device for pyrolyzing organic solid waste to extract hydrogen, which includes a pyrolysis unit, a combustion chamber 2 and a hydrogen purification unit 3 respectively connected with the pyrolysis unit. A first gas purification unit is provided between the pyrolysis unit and the combustion chamber 2. A second valve is provided between the valve and the hydrogen purification unit 3. Therefore, by controlling the opening and closing of the first valve and the second valve, the pyrolysis gas can be controlled to enter the combustion chamber 2 for secondary combustion, or to enter the hydrogen purification unit 3. Purify hydrogen gas;

The pyrolysis unit is used to pyrolyze organic solid waste. The gas generated by pyrolysis can enter the combustion chamber 2 for secondary combustion. The waste heat generated by the secondary combustion is used to provide heat for the pyrolysis unit to increase the pyrolysis temperature. When the preset temperature is reached, the hydrogen purification unit 3 is used to purify the pyrolysis gas with hydrogen, and a gas supply channel is provided between the hydrogen purification unit 3 and the combustion chamber 2 for the purified gas to return to the combustion chamber 2 .

The working process of extracting hydrogen according to the present invention is as follows:

First, control the initial pyrolysis temperature in the pyrolysis unit between 200 and 400°C, and perform low-temperature pyrolysis of the organic solid waste. At this time, the hydrogen content in the pyrolysis gas is low, only about 5%. If Extraction of hydrogen at this time is less economical; therefore, the second valve is controlled to open and the first valve is closed, and the pyrolysis gas enters the combustion chamber 2 for secondary combustion, and the waste heat generated will continue to provide heat for the pyrolysis unit. , when the temperature in the pyrolysis unit increases to 800°C, the hydrogen content in the pyrolysis gas is relatively high. At this time, the first valve can be controlled to open, the second valve can be closed, and the pyrolysis gas enters the hydrogen purification unit 3 for purification. The remaining gas returns to the combustion chamber 2 to continue burning, continuing to provide heat for the pyrolysis unit, ensuring that the temperature in the pyrolysis unit is maintained above 800°C, and ensuring the production of hydrogen.

In this way, the present invention first performs low-temperature pyrolysis of organic solid waste, and allows the pyrolysis gas to enter the combustion chamber 2 for secondary combustion, and fully utilizes the waste heat generated by the secondary combustion to provide heat to the pyrolysis unit, so that the pyrolysis temperature Reaching the preset temperature not only realizes the recycling of waste heat, increases the production of hydrogen, but also saves energy and reduces energy consumption, which has good economic benefits; at the same time, it greatly reduces the emission of carbon dioxide, and the total amount of other gases except hydrogen is basically It remains unchanged and significantly contributes to carbon neutrality.

Among them, in this embodiment, the pyrolysis unit is a low-temperature magnetization pyrolysis furnace 1, which is used for low-temperature magnetization pyrolysis of organic solid waste. The initial temperature in the low-temperature magnetization pyrolysis furnace 1 can be set to 200 to 400°C.

Low-temperature magnetization pyrolysis means that magnetized air is introduced into the pyrolysis furnace. After the air is magnetized, the activity of oxygen in the air is greatly increased, thus reducing the amount of air entering the furnace. On the one hand, it can reduce energy consumption; on the other hand, It also correspondingly reduces the content of nitrogen entering the furnace and increases the calorific value of pyrolysis combustible gas. At the same time, the pyrolyzed solid waste is also magnetized, the cohesion between molecules is reduced, and the pyrolysis effect is effectively improved.

Specifically, the low-temperature magnetization pyrolysis furnace 1 may include a thermal decomposition chamber and a feed bin located on the thermal decomposition chamber. The feed bin is connected to the thermal decomposition chamber. A screen for carrying garbage is provided in the thermal decomposition chamber. An ash cleaning device is provided below the screen for discharging the incinerated ash from the thermal decomposition chamber; an air chamber is provided outside the thermal decomposition chamber, and multiple air chambers are provided on the air chamber for air to enter the thermal decomposition chamber from the air chamber. The air duct is provided with an oxygen magnetizing device outside the feed bin, and the oxygen magnetizing device is connected with an air pipe for inputting oxygen in the magnetized air into the air chamber.

By using the above-mentioned low-temperature magnetization pyrolysis furnace 1, when the organic solid phase garbage is processed, the igniter is first ignited on the screen, and then the organic solid phase garbage is put in from the material opening, and the garbage falls onto the screen; At the same time, the oxygen in the air is magnetized by the oxygen magnetizing device, and the magnetized oxygen is sent to the air chamber through the trachea. The magnetized oxygen fills the air chamber, and then enters the thermal decomposition chamber through the air duct to mix with the garbage on the screen. After full contact, the air containing a large amount of magnetized oxygen is forced into the thermal decomposition chamber to pressurize the thermal decomposition chamber, making the garbage magnetized and decomposed more fully; the ash generated after the decomposition of the garbage is automatically sent out of the thermal decomposition chamber through the ash cleaning device. , the whole process is efficient.

Among them, the temperature in the combustion chamber 2 can be set to above 1100°C. Of course, since the main function of the combustion chamber 2 is to provide heat for the low-temperature magnetization pyrolysis furnace 1, the temperature in the combustion chamber 2 is not strictly limited, as long as it can ensure that the temperature in the low-temperature magnetization pyrolysis furnace 1 can be stabilized at It can be above 800°C, and can be stabilized between 800°C and 950°C. At this time, the hydrogen production is high and the economic benefits are good.

At the same time, the combustion chamber 2 supplies heat to the low-temperature magnetization pyrolysis furnace 1. Specifically, a heat supply pipe can be provided inside the low-temperature magnetization pyrolysis furnace 1. The combustion chamber 2 is provided with an exhaust gas outlet channel, and the exhaust gas outlet channel is connected to the heat supply pipe. In this way, the exhaust gas generated after the secondary combustion can enter the heating pipe to provide heat to the low-temperature magnetization pyrolysis furnace 1 and increase the pyrolysis temperature.

In practical applications, the heat supply pipe can also be arranged in the interlayer of the low-temperature magnetization pyrolysis furnace 1.

Further, it also includes a temperature detection unit arranged in the pyrolysis unit, and a controller. The temperature detection unit is used to monitor the pyrolysis temperature. The temperature detection unit, the first valve, and the second valve are all electrically connected to the controller. The controller can control the opening and closing of the first valve and the second valve according to the monitoring results of the temperature detection unit. Specifically, when the temperature detection unit detects that the pyrolysis temperature is lower than 800°C, the controller controls the first valve to open, and the second valve is opened. The second valve is closed, and the pyrolysis gas enters the combustion chamber 2 for full combustion; when the temperature detection unit detects that the pyrolysis temperature reaches 800°C, the controller controls the first valve to close, the second valve to open, and the pyrolysis gas enters the hydrogen purification unit 3 , carry out hydrogen purification, and effectively improve the intelligence level of the present invention.

Please refer to Figures 2 and 3. Figure 2 is a schematic structural diagram of the hydrogen purification unit in the device for pyrolyzing organic solid waste to extract hydrogen in Figure 1; Figure 3 is a schematic flow chart of the hydrogen purification unit in Figure 2.

In the present invention, the hydrogen purification unit 3 includes a membrane separation device 32, a first compressor 33 and a pressure swing adsorption device 34 connected in sequence. The membrane separation device 32 includes at least two-stage membrane separators, and the pyrolysis gas first passes through the two-stage membranes. The separator performs secondary purification, and the pressure after membrane purification is about 0.1MPa. It is then pressurized to 1.0-1.5MPa through the first compressor 33 and enters the pressure swing adsorption device 34 for three purifications, finally obtaining hydrogen with a purity of more than 99.99%.

Among them, the purification of incoming hydrogen gas using the membrane separation device 32 and the pressure swing adsorption device 34 is a mature process in the existing technology, and will not be described again here.

Furthermore, it also includes a second compressor and a buffer tank 31 connected in sequence to facilitate temporary storage of the pyrolysis gas. The outlet of the buffer tank 31 is connected to the membrane separation device 32.

It also includes a third compressor and a gas storage tank 35 connected in sequence. The high-purity hydrogen purified by the pressure swing adsorption device 34 is compressed by the third compressor and stored in the gas storage tank 35 to facilitate storage, transportation and subsequent use. .

In addition, it also includes a post-processing unit 4 connected to the combustion chamber 2, which is used to post-process the exhaust gas generated after combustion. The exhaust gas will be discharged after it meets the requirements of the "Domestic Waste Incineration Pollution Control Standard" to avoid pollution to the environment. , more green and environmentally friendly.

The present invention also provides a method for pyrolyzing organic solid waste to extract hydrogen. Based on the aforementioned device for pyrolyzing organic solid waste to extract hydrogen, it includes the following steps:

The initial temperature in the pyrolysis unit is controlled, the first valve is opened, and the second valve is closed. The pyrolysis unit pyrolyzes the organic solid waste, and the generated pyrolysis gas enters the combustion chamber 2 for secondary combustion. The waste heat provides heat for the pyrolysis unit;

When the temperature in the pyrolysis unit reaches the preset temperature, the first valve is controlled to close and the second valve is opened. The generated pyrolysis gas enters the hydrogen purification unit 3 for hydrogen purification, and the remaining gas returns to the combustion chamber 2 to continue burning. The pyrolysis unit is supplied with heat to maintain the pyrolysis temperature above a preset temperature.

The method for extracting hydrogen from pyrolyzing organic solid waste of the present invention is applicable to the aforementioned device for extracting hydrogen from pyrolyzing organic solid waste. Therefore, it has the same technical effect as the aforementioned device for extracting hydrogen from pyrolyzing organic solid waste, and will not be described again here.

Among them, the initial temperature of the above-mentioned pyrolysis unit is 200-400°C, and the preset temperature is 800°C.

In practical applications, the pyrolysis temperature can be maintained at 800°C to 950°C. At this time, the economic benefits are high and the hydrogen production is stable.

The device and method for extracting hydrogen from pyrolysis organic solid waste provided by the present invention have been introduced in detail above. Specific examples are used in this article to illustrate the principles and embodiments of the present invention. The description of the above examples is only for Help understand the method of the present invention and its core ideas. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of the claims of the present invention.

Claims (8)

1. A device for pyrolyzing organic solid waste to extract hydrogen, characterized in that it includes a pyrolysis unit, a combustion chamber (2) and a hydrogen purification unit (3) respectively connected to the pyrolysis unit, and the pyrolysis unit A first valve is provided between the unit and the combustion chamber (2), and a second valve is provided between the unit and the hydrogen purification unit (3); The pyrolysis unit is used to pyrolyze organic solid waste. The gas generated by pyrolysis can enter the combustion chamber (2) for secondary combustion. The waste heat generated by the secondary combustion is used to provide energy for the pyrolysis unit. To provide heat, the hydrogen purification unit (3) is used to purify the pyrolysis gas with hydrogen, and a gas supply channel is provided between the hydrogen purification unit (3) and the combustion chamber (2) for The purified gas returns to the combustion chamber (2); The initial temperature in the pyrolysis unit is 200-400°C; under stable working conditions, the temperature in the pyrolysis unit is 800-950°C; The combustion chamber (2) is provided with an exhaust gas outlet channel, and a heat supply pipe is provided inside the pyrolysis unit and communicates with the exhaust gas outlet channel. 2. The device for pyrolyzing organic solid waste to extract hydrogen according to claim 1, characterized in that the pyrolysis unit is a low-temperature magnetization pyrolysis furnace (1); Or, the temperature in the combustion chamber (2) is above 1100°C. 3. The device for extracting hydrogen from pyrolysis organic solid waste according to claim 1, further comprising a temperature detection unit disposed in the pyrolysis unit, and a controller, the temperature detection unit is used to detect heat The temperature detection unit, the first valve, and the second valve are all electrically connected to the controller, and the controller can control the first temperature according to the monitoring result of the temperature detection unit. valve and the opening and closing of the second valve. 4. The device for extracting hydrogen from pyrolysis organic solid waste according to any one of claims 1 to 3, characterized in that the hydrogen purification unit (3) includes a membrane separation device (32) connected in sequence, a first compression machine (33) and a pressure swing adsorption device (34), the membrane separation device (32) includes at least two-stage membrane separators, and the first compressor (33) is used to purify the membrane separation device (32) The subsequent gas is pressurized. 5. The device for extracting hydrogen from pyrolysis organic solid waste according to claim 4, characterized in that it also includes a second compressor and a buffer tank (31) connected in sequence, and the pyrolysis gas is compressed by the second compressor. After being compressed, it is stored in the buffer tank (31), and the outlet of the buffer tank (31) is connected to the membrane separation device (32). 6. The device for extracting hydrogen from pyrolysis organic solid waste according to claim 4, characterized in that it also includes a third compressor and a gas storage tank (35) connected in sequence, and the pressure swing adsorption device (34) purifies The resulting hydrogen is compressed by the third compressor and stored in the gas storage tank (35). 7. The device for extracting hydrogen from pyrolysis organic solid waste according to claim 1, further comprising a post-processing unit (4) connected to the tail gas outlet channel for post-processing the tail gas generated after combustion. , and discharge it after reaching the standard. 8. A method for pyrolyzing organic solid waste to extract hydrogen, based on the device for pyrolyzing organic solid waste to extract hydrogen according to any one of claims 1-7, characterized in that it includes the following steps: The pyrolysis unit is controlled to have an initial temperature, the first valve is opened, and the second valve is closed. The pyrolysis unit pyrolyzes the organic solid waste, and the generated pyrolysis gas enters the combustion chamber (2) for secondary combustion. The waste heat generated by the secondary combustion provides heat for the pyrolysis unit; When the pyrolysis temperature in the pyrolysis unit reaches the preset temperature, the first valve is controlled to close, the second valve is opened, and the generated pyrolysis gas enters the hydrogen purification unit (3) for purification of hydrogen. The gas returns to the combustion chamber (2) to continue burning, and continues to provide heat to the pyrolysis unit to keep the pyrolysis temperature above the preset temperature; The initial temperature is 200-400°C, and the preset temperature is 800-950°C.