Zero-emission methanol preparation equipment based on garbage gasification and water electrolysis

Abstract

The embodiment of the utility model provides zero-emission methanol preparation equipment based on garbage gasification and water electrolysis. The equipment comprises a water electrolysis hydrogen production unit, a garbage gasification unit, a first methanol synthesis unit, a second methanol synthesis unit and a gas separation unit, the water electrolysis hydrogen production unit is respectively connected with the garbage gasification unit, the first methanol synthesis unit and the second methanol synthesis unit; the gas separation unit is respectively connected with the garbage gasification unit, the first methanol synthesis unit and the second methanol synthesis unit; the water electrolysis hydrogen production unit generates hydrogen and oxygen through electrolysis; the garbage gasification unit is used for carrying out gasification reaction by using oxygen provided by the water electrolysis hydrogen production unit to prepare synthesis gas containing carbon monoxide, carbon dioxide and hydrogen; the gas separation unit is used for separating carbon monoxide, carbon dioxide and hydrogen in the synthesis gas introduced from the garbage gasification unit, the carbon monoxide and the hydrogen are introduced into the first methanol synthesis unit, and the carbon dioxide is introduced into the second methanol synthesis unit for preparing methanol respectively.

Description

Technical Field

[0001] The embodiments disclosed herein belong to the field of methanol preparation technology, specifically relating to a zero-emission methanol preparation device based on waste gasification and water electrolysis. Background Technology

[0002] Methanol synthesis is an important process in the chemical industry, using a variety of raw materials, including natural gas, naphtha, heavy oil, coal, and their processed products. As one of the main raw materials in the organic chemical industry, methanol has a wide range of applications, such as in the manufacture of formaldehyde, dimethyl terephthalate (DMT), methyl methacrylate (MMA), methylamine, polyvinyl alcohol, chloromethanes, and acetic acid. It can also be used as a solvent and fuel.

[0003] High-temperature gasification (HTG) for hydrogen production from waste is primarily based on a thermochemical process. It converts organic matter in waste into hydrogen-rich syngas through a high-temperature gasification reaction. During this process, organic matter is decomposed into syngas, mainly composed of hydrogen, carbon monoxide, and methane, under anaerobic and high-temperature conditions. Inorganic matter is melted into metals and glassy slag, which can be used as raw materials for roadbeds and building materials. Like coal gasification for methanol production, this method generates large amounts of carbon dioxide and other pollutants, placing significant pressure on the environment. With increasing global environmental regulations, this production method faces growing environmental pressure.

[0004] Meanwhile, the syngas produced by high-temperature gasification of waste has insufficient hydrogen content. If it is used directly as a raw material for methanol synthesis, the following problems will occur:

[0005] I. Effects on reaction rate and conversion rate, including:

[0006] Decreased reaction rate: Methanol synthesis mainly depends on the reaction of carbon monoxide (CO) and hydrogen (H2). When the hydrogen content is insufficient, the effective number of collisions between CO and H2 decreases, leading to a decrease in the reaction rate.

[0007] Reduced conversion rate: Insufficient hydrogen will limit the amount of methanol produced, because methanol synthesis requires sufficient hydrogen to react with CO. Therefore, insufficient hydrogen content will directly lead to a decrease in the conversion rate of methanol.

[0008] II. The impact on catalyst performance, including:

[0009] Decreased catalyst activity: In the methanol synthesis reaction, catalysts (such as copper-based catalysts) play a crucial role. However, insufficient hydrogen content may lead to incomplete utilization of the active sites of the catalyst, thus affecting the overall activity of the catalyst.

[0010] Shortened catalyst life: Insufficient hydrogen may also lead to an increase in side reactions, such as the disproportionation of CO. These side reactions will generate byproducts such as carbon deposits, which will cover the catalyst surface, leading to catalyst deactivation or poisoning, and thus shortening the catalyst's life.

[0011] III. The impact on product distribution, including:

[0012] Increased byproducts: When hydrogen is insufficient, in addition to methanol, more byproducts such as hydrocarbons, ethers, lipids, and ketones may be generated. The formation of these byproducts not only reduces the purity of methanol but also increases the difficulty of subsequent separation and purification.

[0013] Methanol quality decline: Due to the increase of by-products and the decrease in methanol conversion rate, the quality of the final methanol product may decline, such as insufficient purity or high impurity content.

[0014] IV. Impacts on energy consumption and costs, including:

[0015] Increased energy consumption: To compensate for the impact of insufficient hydrogen on the reaction rate and conversion, it may be necessary to increase reaction temperature or pressure, which will increase energy consumption. At the same time, due to the increase in by-products and the shortening of catalyst life, more energy is required for subsequent processing and catalyst replacement.

[0016] Increased costs: Insufficient hydrogen content leads to decreased methanol production, reduced quality, and increased energy consumption, all of which directly increase production costs. Furthermore, frequent catalyst replacements and byproduct disposal also incur additional costs.

[0017] Therefore, how to solve the above problems has become a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0018] The embodiments disclosed herein aim to at least solve one of the technical problems existing in the prior art, and provide a zero-emission methanol preparation device based on waste gasification and water electrolysis.

[0019] The first aspect of the embodiments of this disclosure provides a zero-emission methanol preparation device based on waste gasification and water electrolysis, comprising: a water electrolysis hydrogen production unit, a waste gasification unit, a first methanol synthesis unit, a second methanol synthesis unit, and a gas separation unit;

[0020] The water electrolysis hydrogen production unit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively; the gas separation unit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively.

[0021] The water electrolysis hydrogen production unit electrolyzes to produce hydrogen and oxygen; the waste gasification unit uses the oxygen provided by the water electrolysis hydrogen production unit to perform a gasification reaction to produce syngas including carbon monoxide, carbon dioxide and hydrogen; the gas separation unit is used to separate carbon monoxide, carbon dioxide and hydrogen in the syngas fed into the waste gasification unit, so that carbon monoxide and hydrogen are fed into the first methanol synthesis unit and carbon dioxide is fed into the second methanol synthesis unit.

[0022] The first methanol synthesis unit produces methanol from hydrogen and carbon monoxide, while the second methanol synthesis unit produces methanol from carbon dioxide and hydrogen provided by the water electrolysis hydrogen production unit.

[0023] Optionally, the gas separation unit includes a methanol cleaning subunit and a heating subunit. The methanol cleaning subunit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively. The methanol cleaning subunit is used to remove acidic gases from the synthesis gas introduced by the waste gasification unit, so that hydrogen and carbon monoxide in the introduced gas can flow to the first methanol synthesis unit.

[0024] The heating subunit is used to heat the methanol cleaning subunit so that the carbon dioxide dissolved in the methanol cleaning subunit is separated and flows to the second methanol synthesis unit.

[0025] Optionally, it also includes a sulfur recovery unit connected to the methanol cleaning subunit, wherein the sulfur recovery unit is used to reduce the sulfur component of the acid gas to sulfur.

[0026] Furthermore, it also includes a waste drying unit, which is used to dry waste.

[0027] Furthermore, it also includes a waste screening unit, which is used to screen waste and transport the screened waste to a waste drying unit.

[0028] Furthermore, it also includes a waste crushing unit, which is used to crush the waste and transport the crushed waste to the waste screening unit.

[0029] Furthermore, it also includes: an odor treatment unit and a leachate treatment unit, wherein the odor treatment unit is used to deodorize the odor generated by the waste; and the leachate treatment unit is used to collect the leachate generated by the waste and transport it to the leachate treatment station.

[0030] The beneficial effects of the embodiments of this disclosure include:

[0031] In this disclosure, a waste gasification unit is used to achieve waste recycling, which is beneficial to environmental protection. In addition, the waste gasification unit and the water electrolysis hydrogen production unit compensate each other for raw materials, so that the raw material ratio of the two synthesis units is reasonable, ensuring the quality of methanol, while avoiding material waste and pollutant emissions. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a zero-emission methanol preparation device based on waste gasification and water electrolysis, according to an embodiment of this disclosure.

[0033] Figure 2 This is a schematic diagram of a zero-emission methanol preparation device based on waste gasification and water electrolysis, according to another embodiment of this disclosure. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] The embodiments of this application will be further described in detail below with reference to the accompanying drawings and examples. The detailed descriptions and accompanying drawings of the following embodiments are used to exemplarily illustrate the principles of this application, but should not be used to limit the scope of this application; that is, this application is not limited to the described embodiments. In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicating orientation or positional relationships are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range.

[0036] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application depending on the specific circumstances.

[0037] like Figure 1 As shown, a zero-emission methanol preparation device based on waste gasification and water electrolysis is disclosed. The device includes a water electrolysis hydrogen production unit, a waste gasification unit, a first methanol synthesis unit, a second methanol synthesis unit, and a gas separation unit.

[0038] The water electrolysis hydrogen production unit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively. The gas separation unit is also connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively.

[0039] The water electrolysis unit produces hydrogen and oxygen through electrolysis. The waste gasification unit uses the oxygen provided by the water electrolysis unit to perform a gasification reaction to produce syngas, which includes carbon monoxide, carbon dioxide, and hydrogen. The gas separation unit separates the carbon monoxide, carbon dioxide, and hydrogen from the syngas introduced from the waste gasification unit, allowing the carbon monoxide and hydrogen to be introduced into the first methanol synthesis unit, and the carbon dioxide to be introduced into the second methanol synthesis unit.

[0040] The first methanol synthesis unit produces methanol from hydrogen and carbon monoxide, while the second methanol synthesis unit produces methanol from carbon dioxide and hydrogen provided by the water electrolysis unit.

[0041] In some embodiments, the waste gasification unit uses waste or RDF fuel as the feedstock for the gasification reaction. Using waste or RDF fuel can replace bituminous coal, achieving resource recycling.

[0042] In this disclosure, a waste gasification unit is used to achieve waste recycling, which is beneficial to environmental protection. In addition, the waste gasification unit and the water electrolysis hydrogen production unit compensate each other for raw materials, so that the raw material ratio of the two synthesis units is reasonable, ensuring the quality of methanol, while avoiding material waste and pollutant emissions.

[0043] In some embodiments, the gas separation unit includes a methanol cleaning subunit and a heating subunit. The methanol cleaning subunit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively. The methanol cleaning subunit is used to remove acidic gases from the synthesis gas introduced by the waste gasification unit so that hydrogen and carbon monoxide in the introduced gas can flow to the first methanol synthesis unit.

[0044] The heating subunit is used to heat the methanol washing subunit so that the carbon dioxide dissolved in the methanol washing subunit is separated and flows to the second methanol synthesis unit.

[0045] In some embodiments, the preparation apparatus further includes a sulfur recovery unit connected to a methanol cleaning subunit, which is used to reduce the sulfur component of the acidic gas to sulfur.

[0046] refer to Figure 2In some embodiments, the methanol production equipment further includes a waste drying unit for drying the waste. Drying the waste using this unit can significantly increase its calorific value and reduce its volume, thereby more effectively producing RDF fuel (waste-derived fuel). Additionally, drying can reduce the moisture content of the waste, thus improving gasification efficiency.

[0047] In some embodiments, the methanol preparation equipment further includes a waste screening unit for screening waste and conveying the screened waste to a waste drying unit.

[0048] The beneficial effects of using waste sorting units include:

[0049] 1. The waste screening unit can effectively remove large debris (such as stones and metals) and small impurities (such as dust and sand), thereby reducing the burden on subsequent processing equipment.

[0050] 2. The screened waste is more uniform, which helps to improve the working efficiency of the waste drying unit and other processing equipment.

[0051] 3. The screening process can remove substances that are not suitable for use as RDF fuel, ensuring that the final RDF fuel has a higher calorific value and more stable combustion performance.

[0052] 4. By screening, the particle size of the material entering the waste drying unit can be controlled, making the dried material more suitable for further processing into high-quality RDF fuel.

[0053] 5. After removing unnecessary impurities, the waste drying unit and other processing equipment can work more efficiently, thereby reducing the energy consumption of the entire system.

[0054] In some embodiments, the waste screening unit includes a multi-panel screen, a magnetic separator, and an air separator, through which RDF raw materials are obtained from municipal solid waste through multi-stage screening using the multi-panel screen, magnetic separator, and air separator.

[0055] In some embodiments, the methanol preparation equipment further includes a waste crushing unit for crushing waste and conveying the crushed waste to the waste screening unit.

[0056] The benefits of using waste shredding units include:

[0057] 1. The waste crushing unit can break large pieces of waste into smaller, more uniform particles, which helps to ensure consistency and efficiency in subsequent waste screening and drying processes.

[0058] 2. Crushed waste materials are easier to accurately screen through the waste screening unit, removing unnecessary impurities.

[0059] 3. The crushed waste has a smaller volume and surface area, which allows it to reach the required degree of dryness more quickly during the waste drying process, thereby reducing the overall processing time.

[0060] 4. Uniform small particles can be more evenly distributed in the processing equipment, improving the equipment's working efficiency and stability.

[0061] 5. The crushed waste has a larger surface area, which is conducive to moisture evaporation and organic matter decomposition, thereby increasing the calorific value of the final RDF fuel.

[0062] 6. Uniform small particles are more stable during combustion, reducing incomplete combustion and improving combustion efficiency and environmental performance.

[0063] In some embodiments, the waste crushing unit includes a coarse crusher to initially crush the waste for subsequent sorting.

[0064] In some embodiments, the methanol preparation equipment further includes an odor treatment unit for deodorizing odors generated from waste.

[0065] The beneficial effects of using an odor treatment unit include:

[0066] 1. The odor control unit, through effective deodorization technology, can significantly reduce the malodorous gases generated in waste storage ponds and during the treatment process, providing a cleaner and more comfortable working environment.

[0067] 2. The highly efficient odor treatment unit can ensure that the treated gas meets national and local emission standards, avoiding fines or legal action due to excessive emissions.

[0068] 3. Odorous gases may contain corrosive components. Effective odor treatment can reduce the corrosion of equipment and buildings by these gases and extend their service life.

[0069] 4. Reduce equipment damage and repair frequency caused by malodorous gases, thereby reducing maintenance costs.

[0070] In some embodiments, the methanol production equipment further includes a leachate treatment unit for collecting leachate generated from waste and transporting it to a leachate treatment station.

[0071] The beneficial effects of using a permeate treatment unit include:

[0072] 1. Liquids typically contain high concentrations of organic matter, heavy metals, and other harmful substances. Effective collection and treatment can prevent these pollutants from entering the soil and groundwater, protecting the environment from pollution.

[0073] 2. After treatment at the leachate treatment station, the leachate can meet national and local emission standards, ensuring that it will not have a negative impact on the environment.

[0074] 3. Effective management of permeate can reduce equipment damage and downtime caused by permeate leakage or improper handling, thereby improving overall production efficiency.

[0075] One specific example provided in this disclosure includes:

[0076] The proposed solution includes the following steps: the preparation equipment comprises a water electrolysis hydrogen production unit, a waste gasification unit, a first methanol synthesis unit, a second methanol synthesis unit, and a gas separation unit. Specifically:

[0077] (1) Electrolysis water hydrogen production unit

[0078] (1-1) Water is injected into the electrolysis hydrogen production unit to produce H2 and O2.

[0079] (1-2) A portion of H2 enters the first methanol synthesis unit to replenish the H2 content, ensuring the reaction rate and purity of methanol production in the first methanol synthesis unit.

[0080] (1-3) Another portion of H2 enters the second methanol synthesis unit and is used to produce methanol in the second methanol synthesis unit.

[0081] (1-4) O2 enters the waste gasification unit, participates in the waste gasification reaction, produces syngas, and at the same time assists in combustion and provides heat.

[0082] (2) Waste gasification unit

[0083] (2-1) The waste gasification unit ensures the temperature and oxygen environment required for the reaction. Syngas (main components: CO, CO2, H2) is generated through the reaction and enters the gas separation unit, which includes a methanol washing subunit and a heating subunit.

[0084] (2-2) The synthesis gas is cleaned and separated by the gas methanol cleaning subunit so that CO and H2 enter the first methanol synthesis unit.

[0085] (2-3) The methanol cleaning subunit is heated by the heating subunit to separate the CO2 dissolved in the low-temperature methanol and enter the second methanol synthesis unit for methanol production.

[0086] (3) Gas separation unit

[0087] The gas separation unit includes a methanol washing subunit and a heating subunit. The methanol washing subunit stores a low-temperature methanol solution. Utilizing the characteristic that methanol has extremely high solubility for acidic gases (such as CO2, H2S, COS, etc.) at low temperatures, these acidic gases are removed from the feed gas and introduced into the sulfur recovery unit.

[0088] (4) Sulfur recovery unit

[0089] The sulfur components (H2S, COS) in the discharged acidic gas are reduced to sulfur and stored.

[0090] (5) First methanol synthesis unit

[0091] (5-1) Main reaction:

[0092]

[0093] (5-2) Secondary reactions:

[0094] CO2+3H2→CH3OH+H2O (ΔH=-58kJ / mol)

[0095] (6) Second methanol synthesis unit

[0096] reaction:

[0097] CO2+3H2→CH3OH+H2O (ΔH=-58kJ / mol).

[0098] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.

Claims

1. A zero-emission methanol preparation device based on waste gasification and water electrolysis, characterized in that, include: The unit consists of a water electrolysis hydrogen production unit, a waste gasification unit, a first methanol synthesis unit, a second methanol synthesis unit, and a gas separation unit. The water electrolysis hydrogen production unit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively; the gas separation unit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively. The water electrolysis hydrogen production unit electrolyzes to produce hydrogen and oxygen; the waste gasification unit uses the oxygen provided by the water electrolysis hydrogen production unit to perform a gasification reaction to produce syngas including carbon monoxide, carbon dioxide and hydrogen; the gas separation unit is used to separate carbon monoxide, carbon dioxide and hydrogen in the syngas fed into the waste gasification unit, so that carbon monoxide and hydrogen are fed into the first methanol synthesis unit and carbon dioxide is fed into the second methanol synthesis unit. The first methanol synthesis unit produces methanol from hydrogen and carbon monoxide, while the second methanol synthesis unit produces methanol from carbon dioxide and hydrogen provided by the water electrolysis hydrogen production unit.

2. The zero-emission methanol preparation equipment based on waste gasification and water electrolysis according to claim 1, characterized in that, The gas separation unit includes a methanol cleaning subunit and a heating subunit. The methanol cleaning subunit is connected to the waste gasification unit, the first methanol synthesis unit, and the second methanol synthesis unit, respectively. The methanol cleaning subunit is used to remove acidic gases from the synthesis gas introduced by the waste gasification unit, so that hydrogen and carbon monoxide in the introduced gas can flow to the first methanol synthesis unit. The heating subunit is used to heat the methanol cleaning subunit so that the carbon dioxide dissolved in the methanol cleaning subunit is separated and flows to the second methanol synthesis unit.

3. The zero-emission methanol preparation equipment based on waste gasification and water electrolysis according to claim 2, characterized in that, Also includes: A sulfur recovery unit is connected to the methanol cleaning subunit, and the sulfur recovery unit is used to reduce the sulfur component of acidic gas to sulfur.

4. The zero-emission methanol preparation equipment based on waste gasification and water electrolysis according to claim 1, characterized in that, Also includes: Waste drying unit, which is used to dry waste.

5. The zero-emission methanol preparation equipment based on waste gasification and water electrolysis according to claim 4, characterized in that, Also includes: A waste screening unit is used to screen waste and then transport the screened waste to a waste drying unit.

6. The zero-emission methanol preparation equipment based on waste gasification and water electrolysis according to claim 5, characterized in that, Also includes: The waste crushing unit is used to crush waste and transport the crushed waste to the waste screening unit.

7. The zero-emission methanol preparation equipment based on waste gasification and water electrolysis according to claim 6, characterized in that, Also includes: The odor treatment unit and the leachate treatment unit are provided, wherein the odor treatment unit is used to deodorize the odor generated by the waste. The leachate treatment unit is used to collect leachate generated from waste and transport it to the leachate treatment station.

Images