Biomass pyrolysis volatile component fractionation and on-line catalysis system and biomass pyrolysis volatile component fractionation and on-line catalysis method

Abstract

The invention relates to the technical field of renewable energy source development and utilization, and particularly discloses a biomass pyrolysis volatile component fractionation and on-line catalysis system and method.The biomass pyrolysis volatile component fractionation and on-line catalysis system comprises a pyrolysis reactor, the pyrolysis reactor is connected with a high-temperature dust remover through a first pipeline, and the high-temperature dust remover is connected with a pyrolysis steam separator through a second pipeline; the pyrolysis steam separator is connected with a first catalytic reactor and a second catalytic reactor through two third pipelines respectively, the first catalytic reactor is connected with a first condenser through a fourth pipeline, the second catalytic reactor is connected with a second condenser through a fifth pipeline, and the first condenser and the second condenser are connected with a tail gas purifier. And the tail gas purifier is connected with the induced draft fan through a seventh pipeline. According to the method, fractionation and online catalysis of biomass pyrolysis steam are achieved, a high-value bio-oil product can be obtained, a large amount of heat loss caused by a conventional fractionation condensation method is avoided, and the energy utilization efficiency is improved while the quality of the bio-oil product is improved.

Description

Technical Field

[0001] This invention relates to the field of renewable energy development and utilization technology, and in particular to a biomass pyrolysis volatilization fractionation and online catalytic system and method. Background Technology

[0002] Biomass, as the only carbon-containing renewable energy source on Earth, can make a significant contribution to my country's dual-carbon goals through large-scale development and utilization. Pyrolysis technology can convert biomass into bio-oil, which has enormous potential to partially replace conventional fossil fuels. However, due to the complex composition and high oxygen content of biomass, its pyrolysis oil contains hundreds of high-oxygen components, posing a significant challenge to its quality improvement. For example, the pyrolysis products of cellulose and hemicellulose, the three major biomass components, mainly include various dehydrated sugars, aldehydes, ketones, acids, and other small-molecule oxygenated organic compounds, while lignin pyrolysis products are mainly composed of larger-molecule phenols and their oligomers. The differences in structure and properties of these oxygenated product components make it difficult to deoxygenate and improve bio-oil using a single method. Therefore, it is necessary to fractionate and separate the components of bio-oil and improve them separately to enhance its utilization value.

[0003] The main existing method for fractional separation of bio-oil components is fractional condensation, which separates the heavy and light components of bio-oil by controlling the condensation temperature. Although this method can effectively separate bio-oil components, it has the following problems: (1) it cannot achieve online upgrading of the fractional components, and the collected condensed oil at each stage still needs to be upgraded offline; (2) the heat released by the high-temperature pyrolysis vapor during the condensation process is not utilized, and the bio-oil still needs to be heated again in the subsequent offline upgrading process, resulting in a huge waste of heat. Therefore, it is urgent to develop a technical means that can simultaneously achieve fractional separation and online upgrading of biomass pyrolysis oil products, so as to break through the existing technical bottlenecks and promote the application of biomass pyrolysis technology.

[0004] Therefore, in order to solve such problems, we propose a biomass pyrolysis volatile matter fractionation and online catalytic system and method. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and to propose a biomass pyrolysis volatile matter fractionation and online catalytic system and method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A biomass pyrolysis volatile matter fractionation and online catalytic system includes a pyrolysis reactor and a high-temperature dust collector. The pyrolysis reactor is connected to the high-temperature dust collector via a first pipe. The high-temperature dust collector is connected to a pyrolysis vapor separator via a second pipe. The pyrolysis vapor separator is connected to a catalytic reactor one and a catalytic reactor two via two third pipes, respectively. The catalytic reactor one is connected to a condenser one via a fourth pipe. The catalytic reactor two is connected to a condenser two via a fifth pipe. The condenser one and the condenser two are connected to a tail gas purifier via two sixth pipes, and the tail gas purifier is connected to an induced draft fan via a seventh pipe.

[0008] Preferably, the pyrolysis reactor includes a reactor, the top of which is connected to a hopper for storing biomass raw materials via an eighth pipe, and the eighth pipe is equipped with a feeder for quantitatively adding biomass to the reactor. An air inlet valve for controlling air flow is provided on the top side of the reactor, and a discharge machine for discharging pyrolysis carbon products is provided at the bottom of the reactor.

[0009] Preferably, the high-temperature dust collector is equipped with ceramic fiber filter bags, a pulse-type soot blower, and a ash discharge port at the bottom for ash removal.

[0010] Preferably, the pyrolysis vapor separator is equipped with a nano-ceramic ultrafiltration membrane in the middle, the micropore size of the nano-ceramic ultrafiltration membrane is between 1-50nm, the two third pipes of the pyrolysis vapor separator correspond to the two sides of the nano-ceramic ultrafiltration membrane respectively, a first pipeline pressure regulating valve is provided on the sixth pipe connected to the first condenser, and a second pipeline pressure regulating valve is provided on the sixth pipe connected to the second condenser.

[0011] Preferably, the catalytic reactor is filled with a heavy oil cracking catalyst, which is a noble metal-based catalyst or a transition metal-based catalyst, and a heating jacket is provided on the outside of the catalytic reactor.

[0012] Preferably, the condenser can be a direct condenser or an indirect condenser, and the bottom of the condenser is provided with a first drain valve.

[0013] Preferably, the interior of the second catalytic reactor is filled with a light oil deoxygenation catalyst or an acidic molecular sieve, and the exterior of the second catalytic reactor is also equipped with a heating jacket. The first pipe, the second pipe, the third pipe, the fourth pipe, and the fifth pipe are all covered with insulation material.

[0014] Preferably, the second condenser can be a direct condenser or an indirect condenser, and the bottom of the second condenser is provided with a second drain valve.

[0015] Preferably, the exhaust gas purifier is filled with organic vapor adsorption material, including biochar and activated carbon.

[0016] A method for fractionation and online catalysis of volatile matter from biomass pyrolysis, the method comprising the following steps:

[0017] Step 1: Biomass undergoes continuous autothermal pyrolysis in pyrolysis reactor 1 to generate high-temperature pyrolysis crude steam;

[0018] Step 2: The high-temperature pyrolysis crude steam enters the high-temperature dust collector 2 to filter out the solid particles in the high-temperature pyrolysis crude steam and obtain clean steam;

[0019] Step 3: The clean steam enters the pyrolysis steam separator 3, where the clean steam is separated into heavy and light components using a nano-ceramic ultrafiltration membrane 3-1;

[0020] Step 4: The heavy component enters the catalytic reactor 4 for online catalytic reaction, and is condensed by the condenser 5 to obtain monophenol products; the light component enters the catalytic reactor 6 for online catalytic reaction, and is condensed by the condenser 7 to obtain low oxygen aldehyde, ketone and hydrocarbon products.

[0021] Step 5: The non-condensable gases discharged from condenser 1 5 and condenser 2 7 are purified by exhaust gas purifier 9 and then discharged into the atmosphere by induced draft fan 10.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention enables the fractional separation and online catalysis of biomass pyrolysis vapors to obtain high-value bio-oil products, while avoiding the large heat loss caused by conventional fractional condensation methods. This improves both the quality of bio-oil products and energy utilization efficiency. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the present invention.

[0026] In the diagram: 1. Pyrolysis reactor; 1-1. Hopper; 1-2. Feeder; 1-3. Reactor; 1-4. Discharge machine; 1-5. Inlet valve; 2. High-temperature dust collector; 3. Pyrolysis vapor separator; 3-1. Nano-ceramic ultrafiltration membrane; 4. Catalytic reactor one; 5. Condenser one; 5-1. First drain valve; 6. Catalytic reactor two; 7. Condenser two; 7-1. Second drain valve; 8-1. First pipeline pressure regulating valve; 8-2. Second pipeline pressure regulating valve; 9. Tail gas purifier; 10. Exhaust fan. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0028] Reference Figure 1 A biomass pyrolysis volatilization fractionation and online catalytic system includes the following main equipment: a pyrolysis reactor 1, a high-temperature dust collector 2, a pyrolysis vapor separator 3, a first catalytic reactor 4, a first condenser 5, a second catalytic reactor 6, a second condenser 7, a tail gas purifier 9, and an induced draft fan 10. All related equipment are connected by pipelines. The pyrolysis reactor 1 is connected to the high-temperature dust collector 2 via a first pipeline. The high-temperature dust collector 2 is connected to the pyrolysis vapor separator 3 via a second pipeline. The pyrolysis vapor separator 3 is connected to the first catalytic reactor 4 and the second catalytic reactor 6 via two third pipelines, respectively. The first catalytic reactor 4 is connected to the first condenser 5 via a fourth pipeline. The second catalytic reactor 6 is connected to the second condenser 7 via a fifth pipeline. The first condenser 5 and the second condenser 7 are each connected to the tail gas purifier 9 via two sixth pipelines. The tail gas purifier 9 is connected to the induced draft fan 10 via a seventh pipeline. The tail gas purifier is filled with organic vapor adsorption material, which includes, but is not limited to, biochar and activated carbon.

[0029] Pyrolysis reactor 1 is a self-heating, continuous-feed fixed-bed reactor. Its main function is to generate heat by burning a portion of the biomass to pyrolyze the remaining biomass. The working process is as follows: Biomass feedstock is stored in hopper 1-1. The biomass is quantitatively added to reactor 1-3 by feeder 1-2, where the pyrolysis reaction takes place. The heat required for the pyrolysis reaction is generated by the combustion of a portion of the biomass, and the air required for combustion enters through inlet valve 1-5, with its flow rate controlled. The biomass feed rate and air flow rate are controlled by feeder 1-2 and inlet valve 1-5, respectively, to maintain the pyrolysis temperature in reactor 1-3 within the range of 400-700℃. The pyrolysis char product is discharged through discharge machine 1-4.

[0030] High-temperature dust collector 2 primarily removes dust from the high-temperature biomass pyrolysis crude steam obtained from the previous pyrolysis reactor 1. It is internally equipped with ceramic fiber filter bags to efficiently filter solid particles from the high-temperature biomass pyrolysis crude steam, yielding clean steam. High-temperature dust collector 2 is also equipped with a pulse-jet blower for timed dust removal to prevent dust from clogging the filter bags. The collected dust is discharged through the bottom ash outlet.

[0031] The pyrolysis vapor separator 3 contains a nano-ceramic ultrafiltration membrane 3-1 with a micropore size between 1-50 nm. Lighter components with molecular dynamic diameters smaller than this pore size can pass through the membrane in the purified vapor after dust removal, while heavier components with larger pore sizes cannot. The nanopore size of the membrane separates the light and heavy components in the purified vapor obtained after dust removal by the high-temperature dust collector 2, avoiding the energy waste caused by conventional condensation and staged separation. Through the pyrolysis vapor separator 3, the purified vapor is separated into heavy and light components.

[0032] Catalytic reactor 4 is a fixed-bed reactor filled with heavy oil cracking catalysts such as noble metal-based catalysts like Pt, Pd, and Ru, or transition metal-based catalysts like Fe, Ni, and Co. It performs an online catalytic reaction on the heavy components separated by pyrolysis vapor separator 3 to prepare monophenolic products. The catalytic reactor 4 is externally equipped with a heating jacket, which can be heated using electric heating or high-temperature flue gas generated from pyrolysis carbon combustion, with the temperature controlled between 400-700℃ to provide a heat source for the catalytic cracking reaction.

[0033] Condenser 5 uses direct condensation (spraying) or indirect condensation (condenser coil) to condense the steam at the outlet of catalytic reactor 4 to obtain liquid upgraded bio-oil rich in phenol monomers, which is discharged through the first drain valve 5-1 at the bottom of condenser 5.

[0034] Catalytic reactor 2 (6) is a fixed-bed reactor filled with light oil deoxygenation catalysts such as amphoteric metal oxides like ZrO2 and CeO2, or acidic molecular sieves like ZSM-5 and MCM-41. It performs an online catalytic reaction on the light components separated by pyrolysis vapor separator 3 to prepare low-oxygen products such as aldehydes, ketones, and hydrocarbons. Catalytic reactor 2 (6) is externally equipped with a heating jacket, which can be heated using electric heating or high-temperature flue gas generated from pyrolysis carbon combustion, with the temperature controlled between 300-600℃ to provide a heat source for the catalytic deoxygenation reaction.

[0035] Condenser 2 7 uses direct condensation (spraying) or indirect condensation (condenser coil) to condense the steam at the outlet of catalytic reactor 2 6 to obtain upgraded bio-oil rich in aldehydes, ketones and hydrocarbons, which is discharged through the second drain valve 7-1 at the bottom of condenser 2 7.

[0036] The two third pipes of the pyrolysis vapor separator 3 correspond to the two sides of the nano-ceramic ultrafiltration membrane 3-1, respectively. A first pipeline pressure regulating valve 8-1 is installed on the sixth pipe connected to condenser 1 5, and a second pipeline pressure regulating valve 8-2 is installed on the sixth pipe connected to condenser 2 7. The main function of the induced draft fan 10 is to discharge non-condensable gases into the atmosphere. Simultaneously, in conjunction with the first and second pipeline pressure regulating valves 8-1 and 8-2, it regulates the pressure difference between the two downstream pipelines of the pyrolysis vapor separator 3 to balance the flow resistance caused by the nano-ceramic ultrafiltration membrane 3-1. The exhaust gas purifier 9 is a tank filled with biochar or activated carbon to adsorb non-condensable organic gases in the exhaust gas, thus purifying the exhaust gas and preventing harmful gases from being released into the atmosphere.

[0037] The biomass pyrolysis volatilization fractionation and online catalytic system covers all pipes between pyrolysis reactor 1 and high-temperature dust collector 2, between high-temperature dust collector 2 and pyrolysis vapor separator 3, between pyrolysis vapor separator 3 and catalytic reactor 4, between pyrolysis vapor separator 3 and catalytic reactor 6, between catalytic reactor 4 and condenser 5, and between catalytic reactor 6 and condenser 7 with thermal insulation material. This is to minimize heat loss from biomass pyrolysis vapor and improve energy utilization efficiency. Specifically, the first, second, third, fourth, and fifth pipes are all covered with insulation material.

[0038] The relevant electrical equipment in this system is controlled by the existing PLC.

[0039] Example 1:

[0040] Biomass undergoes a continuous autothermal pyrolysis reaction in pyrolysis reactor 1. Biomass raw materials are fed into hopper 1-1, and the feed rate is controlled by feeder 1-2. The biomass enters reactor 1-3, and the air flow is controlled by air inlet valve 1-5. The pyrolysis temperature in reactor 1-3 is controlled at 500℃. At this temperature, the biomass undergoes a pyrolysis reaction, generating high-temperature pyrolysis crude steam, which enters high-temperature dust collector 2 through the first pipe at the lower end of reactor 1-3. Solid pyrolysis char is discharged by discharge machine 1-4.

[0041] High-temperature pyrolysis crude steam enters high-temperature dust collector 2, where it is purified by using ceramic fiber filter bags to remove dust. This means filtering out solid particles from the high-temperature pyrolysis crude steam to obtain clean steam, which is the purified high-temperature pyrolysis steam. The clean steam is then blown away by a pulse-type soot blower, and the collected solid particles are discharged from the bottom ash discharge port.

[0042] The purified high-temperature pyrolysis steam (net steam) enters the pyrolysis steam separator 3 through a second pipe. This separator is equipped with a nano-ceramic ultrafiltration membrane 3-1 with an average pore size of 3 nm. The nano-ceramic ultrafiltration membrane 3-1 separates the purified high-temperature pyrolysis steam into heavy and light components. Specifically, small-molecule aldehydes, ketones, acids, and dehydrated sugars in the purified high-temperature pyrolysis steam can pass through the nano-ceramic ultrafiltration membrane 3-1 and then enter the second catalytic reactor 6, while large-molecule phenols and their oligomers cannot pass through and enter the first catalytic reactor 4. The pyrolysis steam separator 3 effectively separates the small-molecule and large-molecule components in the purified high-temperature pyrolysis steam.

[0043] The heavy component enters the catalytic reactor 4, where it undergoes an online catalytic reaction using a cracking catalyst. After condensation in the condenser 5, monophenolic products are obtained. The catalytic reactor 4 is filled with a Ru / C catalyst, and the temperature of the catalytic bed is controlled at 500℃. This catalyst can further crack phenolic oligomers to generate monophenolic substances. The product after catalytic reforming enters the condenser 5 for condensation, and the liquid product rich in monophenolic components is collected. This product can be used as a chemical raw material to prepare high-value phenolic chemicals such as phenol.

[0044] Lighter components enter catalytic reactor 26, where they undergo online catalytic reaction using metal oxides or acidic molecular sieves. After condensation in condenser 27, low-oxygen aldehydes, ketones, and hydrocarbons are obtained. Specifically, catalytic reactor 26 maintains a catalytic bed temperature of 450°C. The bed is filled with CeO2 catalyst, which catalyzes further conversion of small molecule components such as acids, aldehydes, and oligosaccharides to produce aldehydes and ketones. Alternatively, ZSM-5 molecular sieves can be used to prepare olefins, aromatic hydrocarbons, and other hydrocarbons. The products from catalytic reforming then enter condenser 27 for further condensation, collecting the liquid product rich in aldehydes, ketones, and hydrocarbons. This liquid can be used as a chemical raw material to prepare ketone and hydrocarbon chemicals, or further upgraded through hydrodeoxygenation to produce fuel oil.

[0045] Finally, the non-condensable gas is purified by the exhaust gas purifier 9 and discharged into the atmosphere by the induced draft fan 10. In summary, this system can achieve staged separation and online catalysis of biomass pyrolysis vapors to obtain high-value bio-oil products, and avoids the large amount of heat loss caused by conventional staged condensation methods, thereby improving both the quality of bio-oil products and energy utilization efficiency.

[0046] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A biomass pyrolysis volatile matter fractionation and online catalytic system, characterized in that, The device includes a pyrolysis reactor (1) and a high-temperature dust collector (2). The pyrolysis reactor (1) is connected to the high-temperature dust collector (2) through a first pipe. The high-temperature dust collector (2) is connected to a pyrolysis vapor separator (3) through a second pipe. The pyrolysis vapor separator (3) is connected to a catalytic reactor one (4) and a catalytic reactor two (6) through two third pipes, respectively. The catalytic reactor one (4) is connected to a condenser one (5) through a fourth pipe. The catalytic reactor two (6) is connected to a condenser two (7) through a fifth pipe. The condenser one (5) and the condenser two (7) are connected to a tail gas purifier (9) through two sixth pipes, respectively. The tail gas purifier (9) is connected to an induced draft fan (10) through a seventh pipe.

2. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The pyrolysis reactor (1) includes a reactor (1-3). The top of the reactor (1-3) is connected to a hopper (1-1) for storing biomass raw materials through an eighth pipe. The eighth pipe is equipped with a feeder (1-2) for quantitatively adding biomass into the reactor (1-3). An air inlet valve (1-5) for controlling air flow is provided on the top side of the reactor (1-3). The bottom of the reactor (1-3) is equipped with a discharge machine (1-4) for discharging pyrolysis carbon products.

3. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The high-temperature dust collector (2) is equipped with ceramic fiber filter bags and a pulse-type soot blower. The bottom of the high-temperature dust collector (2) is provided with a ash discharge port for ash discharge.

4. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The pyrolysis vapor separator (3) is equipped with a nano-ceramic ultrafiltration membrane (3-1) in the middle. The micropore size of the nano-ceramic ultrafiltration membrane (3-1) is between 1-50nm. The two third pipes of the pyrolysis vapor separator (3) correspond to the two sides of the nano-ceramic ultrafiltration membrane (3-1) respectively. The sixth pipe connected to the condenser one (5) is equipped with a first pipeline pressure regulating valve (8-1), and the sixth pipe connected to the condenser two (7) is equipped with a second pipeline pressure regulating valve (8-2).

5. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The catalytic reactor (4) is filled with a heavy oil cracking catalyst, which is a noble metal-based catalyst or a transition metal-based catalyst. The catalytic reactor (4) is equipped with a heating jacket.

6. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The condenser (5) can be used for direct condensation or indirect condensation, and the bottom of the condenser (5) is provided with a first drain valve (5-1).

7. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The catalytic reactor 2 (6) is filled with light oil deoxygenation catalyst or acidic molecular sieve. The catalytic reactor 2 (6) is also equipped with a heating jacket. The first pipe, second pipe, third pipe, fourth pipe and fifth pipe are all covered with heat insulation material.

8. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The second condenser (7) can adopt direct condensation or indirect condensation type, and the bottom of the second condenser (7) is provided with a second drain valve (7-1).

9. The biomass pyrolysis volatilization fractionation and online catalytic system according to claim 1, characterized in that, The exhaust gas purifier (9) is filled with organic vapor adsorption materials, including biochar and activated carbon.

10. A method for fractionation and online catalysis of volatile components from biomass pyrolysis, characterized in that, The method includes the following steps: Step 1: Biomass undergoes continuous autothermal pyrolysis in pyrolysis reactor 1 to generate high-temperature pyrolysis crude steam; Step 2: The high-temperature pyrolysis crude steam enters the high-temperature dust collector 2 to filter out the solid particles in the high-temperature pyrolysis crude steam and obtain clean steam; Step 3: The clean steam enters the pyrolysis steam separator 3, where the clean steam is separated into heavy and light components using a nano-ceramic ultrafiltration membrane 3-1; Step 4: The heavy component enters the catalytic reactor 4 for online catalytic reaction, and is condensed by the condenser 5 to obtain monophenol products; the light component enters the catalytic reactor 6 for online catalytic reaction, and is condensed by the condenser 7 to obtain low oxygen aldehyde, ketone and hydrocarbon products. Step 5: The non-condensable gases discharged from condenser 1 5 and condenser 2 7 are purified by exhaust gas purifier 9 and then discharged into the atmosphere by induced draft fan 10.

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