Catalytic fluidization gasification reforming integrated device for efficiently treating organic solid waste to prepare hydrogen-rich fuel gas and treatment method

Abstract

The invention provides a device and a method for efficiently treating organic solid waste to prepare hydrogen-rich fuel gas through integration of catalytic fluidization, gasification and reforming, the device comprises a gasification reaction chamber, a multi-stage high-temperature ventilation dust remover and a reforming reaction chamber which are connected in sequence, and a top outlet of the gasification reaction chamber is connected with a top inlet of the reforming reaction chamber through a connecting pipeline; and the multi-stage high-temperature ventilation dust remover is arranged on the connecting pipeline. The pretreated organic solid waste is subjected to a catalytic gasification reaction in the gasification reaction chamber, a reaction pyrolysis product enters the reforming reaction chamber to be subjected to an in-situ catalytic reforming reaction after being subjected to dust removal and filtration, hydrogen-rich fuel gas is obtained, and a part of hydrogen-rich fuel gas is sent back to the gasification reaction chamber. The whole device is integrally installed, the sealing performance is good, the space size is small, the process is safe and reliable, meanwhile, in the treatment method, the organic solid waste fully reacts under the catalytic action in the gasification reaction chamber and the reforming reaction chamber, hydrogen-rich fuel gas with the higher additional value can be obtained, and economic benefits and environmental benefits are both achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of resource treatment of organic solid waste, and in particular to a device and recycling technology for thermochemical conversion of organic solid waste including kitchen waste, municipal sludge, domestic waste, agricultural and forestry waste, etc. Background Art

[0002] Thermochemical conversion is the most commonly used technical approach to convert organic solid waste into energy, but the components of organic solid waste are complex and changeable, and the multi-component interaction mechanism in the thermochemical conversion process is complex, which makes it difficult to directional control the target product. The complete, efficient and green thermochemical decoupling of organic solid waste into high-value chemicals such as high-performance carbon materials, aromatic-rich liquid fuels and high-quality gas has become a development trend in the energy and resource utilization of organic solid waste, and is also a major scientific issue and key engineering technical problem in the fields of materials, chemicals and new energy.

[0003] At present, the thermochemical conversion technology of organic solid waste mainly includes incineration, pyrolysis and gasification. The prior art CN206904985U discloses a gasification and incineration system for domestic waste, including a gasifier, a secondary combustion chamber, a heat exchange device, an acid removal tower, a bag filter and a chimney. The gasification and incineration furnace includes a combustion chamber. The combustible gas generated by pyrolysis in the first combustion chamber enters the secondary combustion chamber through the gasification connecting pipe on the top of the furnace body. The combustible components in the flue gas entering the secondary combustion chamber are mixed with oxygen supplied by the secondary fan, and oxygen-rich high-temperature combustion is carried out. The temperature is controlled at 850℃~1100℃, which prolongs the residence time of the flue gas and ensures that the combustible gas is burned out. However, organic solid waste pyrolysis-incineration technology faces many challenges: organic solid waste has high water content, complex components, and poor uniformity. The pyrolysis processes of different components interact with each other, making it difficult to convert pyrolysis products into high-value products; the organic solid waste pushing device is prone to deformation at high temperatures during the pyrolysis process, causing the pushing mechanism to get stuck, accompanied by problems such as large heat loss of the workpiece and difficulty in sealing the device; the heat transfer characteristics of materials in traditional pyrolysis furnaces are poor and the heating is uneven, resulting in low pyrolysis efficiency and difficulty in controlling product homogenization; the large volatility of pollutant precipitation during the pyrolysis process makes the emission risk of dioxins, acid gases, heavy metals and other pollutants high.

[0004] In order to solve the technical drawbacks of traditional pyrolysis-gasification, based on the heat transfer-adsorption-catalytic coupling effect of porous media in the pyrolysis and gasification process of organic solid waste particles, a new method of using porous media to directionally control the generation of gas phase products was proposed, and a fluidized bed gasifier with porous media enhanced heat and mass transfer was developed and designed. Summary of the invention

[0005] The present invention discloses a device for efficiently treating organic solid waste to produce hydrogen-rich gas by integrating catalytic fluidized gasification and reforming. The device is an organic solid waste treatment device based on porous medium heat transfer, adsorption and catalysis, and simultaneously realizes reforming to produce hydrogen-rich gas and recycling it as hydrogen-rich gas. The specific structure of the device is as follows:

[0006] A device for efficiently treating organic solid waste to produce hydrogen-rich gas by integrating catalytic fluidized gasification and reforming comprises a gasification reaction chamber, a multi-stage high-temperature ventilation dust collector and a reforming reaction chamber connected in sequence. The top outlet of the gasification reaction chamber is connected to the top inlet of the reforming reaction chamber through a connecting pipe, the multi-stage high-temperature ventilation dust collector is installed on the connecting pipe, a metal nozzle is arranged directly below the bottom of the gasification reaction chamber, a first feed inlet and a second feed inlet are arranged on both sides of the metal nozzle, the gasification medium enters from the first feed inlet, the pretreated solid waste particles enter from the second feed inlet, and the hydrogen-rich gas is sprayed upward from the metal nozzle into the gasification reaction chamber; an outlet is arranged at the bottom of the reforming reaction chamber, the outlet is connected to an induced draft fan, the outlet end of the induced draft fan is connected to the metal nozzle through a pipe, the gasification reaction chamber is filled with a spherical porous Al2O3 catalyst, and the reforming reaction chamber is filled with a brick-type Ni-Mg / Al2O3 catalyst.

[0007] Furthermore, the inner lining of the device is made of high temperature resistant material which is installed in an integrated manner, has good sealing and integrity, and avoids the spillage of pollutants.

[0008] Furthermore, the first feed inlet of the gasification reaction chamber of the device is also connected to a fan, and a flow valve 1 and a flow meter 1 are sequentially arranged between the outlet of the fan and the first feed inlet. A flow valve 2 and a flow meter 2 are sequentially arranged between the air outlet of the reforming reaction chamber of the device and the induced draft fan. Temperature sensor probes and pressure sensor probes are installed in both the gasification reaction chamber and the reforming reaction chamber. Therefore, the device is compact and operates safely and stably.

[0009] Furthermore, the solid waste includes domestic garbage, urban sludge, biomass, kitchen waste, agricultural and forestry waste, etc.

[0010] The heat transfer coefficient of the porous alumina is 480W / m 2 K, specific surface area is 277.94m 2 / g, the porous alumina has pores of different sizes, and the number percentage distribution of pores of different sizes is as follows:

[0011] <6nm 17.31%

[0012] 6~8nm 16.09%

[0013] 8~10nm 12.07%

[0014] 10~12nm 16.08%

[0015] 12~16nm 18.35%

[0016] 16~20nm 14.06%

[0017] 20~80nm 5.89%

[0018] >80nm 0.16%.

[0019] The present invention also proposes a method for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming based on the above device. In the method, the temperature of the gasification reaction chamber is controlled in the range of 650-800°C, and the volume flow rate ratio of the spherical porous Al2O3 filled in the gasification reaction chamber (2) to the volume flow rate of the gasification medium is 3000-5000h -1 The temperature of the reforming reaction chamber is controlled in the range of 700-850°C, and the volume / gas volume flow ratio of the brick-shaped Ni-Mg / Al2O3 catalyst filled in the reforming reaction chamber (9) is 5000-10000h -1 The gas flow velocity range of the gasified medium entering the gasification reaction chamber is 1.0 to 3.0 m / s.

[0020] Furthermore, the solid waste includes one or more of domestic garbage and organic waste.

[0021] Furthermore, the gasification medium is a mixture of one or more of air, oxygen or water vapor.

[0022] Furthermore, after the organic solid waste is treated in the gasification reaction chamber and the reforming reaction chamber, the product distribution is 35-50% hydrogen, 5-40% CO2, 5-10% methane, and 1-3% ethylene.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Compared with traditional gasification devices, this device integrates fluidized bed catalytic gasification and catalytic reforming, improves the sealing degree of the device, and reduces the possibility of pollutant leakage. The range of raw materials used for gasification is relatively wide, including urban domestic waste, urban sludge, biomass, kitchen waste, agricultural and forestry waste, etc. The process technology is very mature, the process is relatively simple, the process is safe and reliable, the equipment is compact, and the operation rate is high.

[0025] 2. A fluidized bed coupled with porous media to enhance heat and mass transfer is selected as the reaction device. Compared with the traditional fixed bed, rotary kiln and fluidized bed, this device uses hot flue gas (including air, oxygen or water vapor or a mixture) as the gasification medium. The air flow speed is faster, and the hydrogen is atomized and burned using a nozzle. It instantly goes through several stages such as distillation, combustion, and reduction. The gasification process has less pollution and good environmental performance.

[0026] 3. Catalysts are added during the pyrolysis and reforming processes to make the gasification pyrolysis reaction and reforming reaction more thorough, converting tar and other gases into synthesis gas with higher hydrogen content, thereby achieving the purpose of reducing greenhouse gases and increasing synthesis gas production, and then synthesizing chemicals and fuels with higher added value, achieving both economic and environmental benefits.

[0027] 4. At the gas outlet of the reforming reaction chamber, the generated hydrogen is transported to the gasification reaction chamber for reuse and heat supply, thereby improving the energy utilization efficiency.

[0028] 5. Porous Al2O3 is used as a catalyst in the fluidized bed gasification reactor. The porous medium can prevent the reactants from agglomerating during the pyrolysis process, ensuring sufficient reaction during the pyrolysis process. At the same time, in the reaction, due to its three-point site, it has a strong catalytic effect during catalysis. Due to the shape characteristics of the material itself, its specific surface area is large, which increases the contact area with the reactants and further enhances its catalytic effect.

[0029] 6. Porous alumina is an excellent material with low thermal conductivity. During the pyrolysis process, it has a lower thermal conductivity than the traditional quartz sand. This means that during the pyrolysis process, the temperature of the organic matter entering will not rise too quickly, and the organic waste will not volatilize too quickly, so that the reactants can fully react in the fluidized bed gasification reactor, reducing the production of tar and VOCS. This can greatly reduce pollution and increase the gas production rate of synthesis gas. Compared with ordinary media, porous media have a strong adsorption effect, with a bhy value of up to 300. During the reaction process, the generated gas and small molecules of tar can be captured and fully reacted, thereby improving the reaction efficiency. At the same time, the reaction of small molecules can make the reaction more thorough and increase the hydrogen content of the synthesis gas.

[0030] 7. In the reforming reactor, due to the existence of carbon deposition and sintering in the reaction process, the conversion rate of CH4 and CO2 decreases. A brick-type Al-based Ni-Mg catalyst is used, which can catalyze the secondary reforming reaction of tar, gas, etc., inhibit the production of tar, and convert the tar and gas produced in the fluidized bed gasification reactor into high-hydrogen content synthesis gas, which can achieve the purpose of reducing greenhouse gases and increasing the production of synthesis gas. Then, chemicals and fuels with higher added value are synthesized, which has both economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of the integrated solid waste treatment device of the present invention;

[0032] Figure 2 is a relationship diagram between the change of gasification reaction chamber temperature and the proportion of gasification product components, wherein Industrialsand is the 180-250 μm quartz sand of Example 3, and Porous media is the spherical porous Al2O3 catalyst of Example 1;

[0033] Figure 3The relationship between fluidizing gas velocity and pressure after filling different materials and catalyst materials in the gasification reaction chamber;

[0034] Figure 4 The relationship between the heat transfer coefficient, reaction temperature and gas flow velocity after filling the gasification reaction chamber with different materials and catalyst materials;

[0035] Figure 5 A diagram showing the rate of cracking gas generation after filling the gasification reaction chamber with different materials and catalyst materials;

[0036] Figure 6 The influence of different materials and catalyst materials filled in the gasification reaction chamber on the main components of tar in the outlet flue gas;

[0037] Figure 7 The effect of filling different materials and catalyst materials in the gasification reaction chamber on the PAHs with different ring numbers in the outlet flue gas;

[0038] Figure 8 is the PAHs toxic equivalent concentration after the gasification reaction chamber is filled with quartz sand and porous alumina catalyst;

[0039] Fig. 9 The XRD spectra of the composite catalyst Ni-Mg-Al system catalyst of the present invention before and after reduction, (a) is the XRD spectrum of the Ni-Mg-Al system catalyst before reduction, (b) is the XRD spectrum of the Ni-Mg-Al system catalyst after reduction;

[0040] Fig.10 The NM in the Ni-Mg-Al system catalyst of the composite catalyst of the present invention 10 A In-situ XRD spectrum of the reduction process;

[0041] Fig.11 This is the H2-TPR spectrum of the composite catalyst Ni-Mg-Al system catalyst of the present invention;

[0042] Fig.12 This is the CO2-TPD spectrum of the composite catalyst Ni-Mg-Al system after catalyst reduction of the present invention;

[0043] Fig.13 The composite catalyst NM of the present invention 10 TEM characterization results of catalyst A after reduction, (a) is the TEM result and particle size distribution diagram, (b) EDS element dispersion diagram, (c) is the HRTEM diagram, and (d) is the SAED diffraction diagram;

[0044] Fig.14The activity evaluation of the composite catalyst Ni-Mg-Al system catalyst of the present invention for reforming the pyrolysis gas of organic solid waste, (a) is the effect of reaction temperature and Mg content on the catalytic effect, (b) is the catalyst stability test result;

[0045] Fig.15 The particle temperature distribution in the gasification reaction chamber of the present invention;

[0046] Among them, 1-spherical porous Al2O3 catalyst, 2-gasification reaction chamber, 3-first feed inlet, 4-second feed inlet, 5-metal nozzle, 6-multi-pole high-temperature ventilation dust collector, 7-connecting pipeline, 8-brick-type Ni-Mg / Al2O3 catalyst, 9-reforming reaction chamber, 10-gas outlet, 201-fan, 202-flow valve one, 203-flow meter one, 101-induced draft fan, 102-flow valve two, 103-flow meter two. DETAILED DESCRIPTION

[0047] The present invention will be further explained below in conjunction with the accompanying drawings and specific implementations. The following specific implementations are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0048] Example 1

[0049] A device for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming, the structure of which is as follows Figure 1 As shown, it mainly includes a gasification reaction chamber 2 and a reforming reaction chamber 9 which are interconnected. Specifically, a first feed port 3 and a second feed port 4 are arranged below the gasification reaction chamber 2. Air enters from the first feed port 3. Biomass and urban domestic waste enter from the second feed port 4 after being pre-treated and carry water vapor. A metal nozzle 5 is arranged just below the bottom of the gasification reaction chamber 2 to provide hydrogen-rich gas to the inside of the gasification reaction chamber 2. The combustion of the hydrogen-rich gas provides heat to the gasification reaction chamber 2 to support its reaction, so that the temperature of the gasification reaction chamber 2 is maintained at about 600-800°C. The first feed port 3 and the second feed port 4 are distributed on both sides of the metal nozzle 5. The gasification reaction chamber 2 is also filled with a spherical porous Al2O3 catalyst. After pretreatment, air, biomass and urban domestic waste enter the gasification reaction chamber 2 at a certain flow rate to undergo pyrolysis and catalytic reaction. Under the action of the spherical porous Al2O3 catalyst (Porous alumina), a mixed pyrolysis product including components such as CO2, CH4, CO, H2, fly ash, and tar is finally produced.

[0050] A fan 201 is provided outside the gasification reaction chamber 2, and air is injected into the gasification reaction chamber 2 through the fan 201. A flow valve 202 and a flow meter 203 are provided in the pipeline for injecting air from the fan 201. The flow valve 201 is used to control the air flow rate supplied to the gasification reaction chamber 2, and the flow meter 203 is used to measure the air flow rate in the pipeline. A temperature sensor probe for monitoring the temperature in the gasification reaction chamber 2 and a pressure sensor probe for monitoring the pressure in the gasification reaction chamber are also provided in the gasification reaction chamber 2. The temperature of the gasification reaction chamber 2 is usually controlled between 600°C and 800°C.

[0051] The top outlet of the gasification reaction chamber 2 is connected to the top inlet of the reforming reaction chamber 9 through a connecting pipe 7. A multi-pole high-temperature dust collector 6 is installed on the connecting pipe 7, which can withstand a temperature range of 600-700°C. The multi-pole high-temperature dust collector 6 will intercept and filter the mixed pyrolysis products of the gasification reaction chamber 2, filter and collect particulate matter such as fly ash, and discharge them at the lower end of the dust collector. The filtered mixed pyrolysis products enter the reforming reaction chamber 9. The reforming reaction chamber 9 is filled with a brick-type Ni-Mg / Al2O3 catalyst 8. An outlet 10 is provided at the bottom of the reforming reaction chamber 9. The outlet 10 is connected to a flow valve 102, a flow meter 103 and an induced draft fan 101 in sequence. The flow valve 102 is used to control the airflow of the reforming reaction chamber 9, and the flow meter 103 is used to measure the flow of gas in the pipeline.

[0052] The filtered mixed pyrolysis product undergoes a reforming reaction with the catalyst. The main reaction is the reaction of carbon dioxide and methane to generate carbon monoxide and hydrogen, generating a large amount of hydrogen-rich gas mixture, which is collected at the gas outlet 10 through the induced draft fan 101 and the synthesis gas is drawn out. A part of the collected mixed gas is returned to the metal nozzle 5 of the gasification reaction chamber 2, and after entering the gasification reaction chamber 2, it is mixed with air and burned. The heat generated by the combustion provides heat to the gasification reaction chamber 2 to support its reaction. A temperature sensor probe for monitoring the temperature in the reforming reaction chamber 9 and a pressure sensor probe for monitoring the pressure in the gasification reaction chamber are also provided in the reforming reaction chamber 9. The temperature of the reforming reaction chamber 9 is usually controlled at 700-850°C.

[0053] From the gasification reaction chamber 2, the connecting pipeline 7, the multi-stage high-temperature dust collector 6 to the reforming reaction chamber 9, high-temperature resistant materials are used for integrated connection and installation to improve the sealing degree of the device and avoid leakage of pollutants.

[0054] The working principle of the device for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming provided by the present invention is as follows: first, before the entire reaction is started, hydrogen-rich fuel gas is introduced into the metal nozzle at the bottom of the gasification reaction chamber, and the gasification medium air is sent to the first feed port through the air supply fan, and the air contacts the hydrogen-rich fuel gas. Through the combustion of the hydrogen-rich fuel gas, the temperature in the gasification reaction chamber gradually increases and reaches the temperature of the catalytic reaction. Here, the air flow velocity of the gasification medium entering the gasification reaction chamber is controlled to be in the range of 1.0 to 3.0 m / s; then, after pretreatment, the solid waste and biomass form crushed and dried solid waste particles, which are continuously added to the gasification reaction chamber from the second feed port, and as the air is transported upward from the bottom of the gasification reaction chamber, the solid waste particles are driven to move upward at the same time. In a high temperature environment, solid waste particles come into contact with the spherical porous Al2O3 catalyst and react, and the solid waste begins to undergo pyrolysis, which is a thermal decomposition process that occurs under oxygen-free or low-oxygen conditions, decomposing the waste into smaller molecules, including combustible gas, liquid (tar) and solid residue (carbon black, fly ash). Here, the spherical porous Al2O3 volume / gasification medium volume flow rate ratio is controlled to be 3000-5000h -1 . At the same time, the combustible gas is mixed with the gasification medium (air, oxygen or water vapor). At high temperature, the combustible gas and the gasification medium react chemically. Under the action of the catalyst, the reaction process is completed faster. The generated gasification products include carbon monoxide, hydrogen, methane, etc., which helps to improve the calorific value and quality of the synthesis gas. At the same time, the catalyst makes the gasification reaction more thorough. The catalyst has a strong adsorption effect, and the bhy value is as high as 300. During the reaction process, the small molecules of the generated gas and tar can be captured and fully reacted, thereby improving its reaction efficiency. At the same time, the reaction of small molecules can make the reaction more thorough, increase the hydrogen content of the synthesis gas, and reduce the generation of tar and VOCS; in addition, the use of catalysts can avoid the formation of pollutants such as dioxins. Then, the mixed pyrolysis products containing solid residues enter the connecting pipe part and enter the multi-pole high-temperature dust collector. Through its dust removal and filtration, the solid residue is filtered and intercepted. The clean mixed gas obtained after filtration enters the reforming reaction chamber.

[0055] In the reforming reaction chamber, the reaction temperature is controlled at 700-850℃. The brick-type Al-based Ni-Mg catalyst can catalyze the reforming reaction of tar, gas, etc., inhibit the production of tar, and convert the tar and gas produced in the gasification reaction chamber into high-hydrogen content synthesis gas, thereby achieving the purpose of reducing greenhouse gases and increasing synthesis gas production. Here, the volume flow rate ratio of the brick-type Ni-Mg / Al2O3 catalyst / gas volume is controlled to be 5000-10000h -1 . And then synthesize chemicals and fuels with higher added value, which has both economic and environmental benefits.

[0056] The reactions occurring in the reforming reaction chamber are as follows:

[0057] CH4+CO2→2CO+2H2 ΔH 298K =+247.0KJ / mol

[0058] CO2+H2→CO+H2O ΔH 298K =+41.2KJ / mol

[0059] CH4→C+2H2 ΔH 298K =+74.8KJ / mol

[0060] One of the main sources of the performance of brick-type Al-based Ni-Mg catalysts is the interaction between metal supports (Metal-Support Interaction, MSI). Strong MSI will have an "anchoring" effect on active metal particles, restricting the migration and aggregation of metal particles and inhibiting the sintering and carbon deposition of catalysts. In addition, alkaline earth metal additives can provide alkaline sites for catalysis. The alkaline sites on the catalyst surface can enhance the chemical adsorption of CO2 and facilitate the elimination of carbon deposition.

[0061] In this device, the organic solid waste is treated in the gasification reaction chamber and the reforming reaction chamber to obtain a product distribution of 35% to 50% hydrogen, 5% to 40% CO2, 5% to 10% methane, and 1% to 3% ethylene.

[0062] Example 2

[0063] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the spherical porous Al2O3 catalyst is replaced by 160-180 μm quartz sand.

[0064] Example 3

[0065] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the spherical porous Al2O3 catalyst is replaced by 180-250 μm quartz sand.

[0066] Example 4

[0067] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the spherical porous Al2O3 catalyst is replaced by 250-320 μm quartz sand.

[0068] Example 5

[0069] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the spherical porous Al2O3 catalyst is replaced by solid nonporous alumina.

[0070] The properties of the fillers in the above examples are shown in Table 1.

[0071] Table 1

[0072]

[0073] Based on the solid waste treatment device integrating gasification catalysis and reforming of the above-mentioned Examples 1 to 5, the spherical porous alumina catalyst and other fillers in the gasification reaction chamber have different effects on the concentrations of small molecular hydrocarbons, monocyclic benzene series and PAHs in the flue gas during the gasification process of organic solid waste.

[0074] like Figure 2 As shown, when different catalyst fillers are filled in the gasification reaction chamber, the distribution of the gasification reaction products is different. The 180-250 μm quartz sand of Example 2 and the spherical porous Al2O3 catalyst of Example 1 pyrolyze biomass and urban domestic waste at 500°C, 600°C, 650°C, and 700°C, respectively. The gas components after pyrolysis of biomass and urban domestic waste by the catalyst of Example 1 at 650°C and 700°C have the highest H2 and CO contents, and the least CO2 and alkanes. Therefore, using spherical porous Al2O3 as a catalyst is more conducive to reducing the emissions of CO2 and alkanes and generating more H2 and CO.

[0075] like Figure 3 As shown, when spherical porous Al2O3 is used as catalyst in Example 1, the reactor resistance is lower. Figure 4 As shown, the thermal conductivity of the filler in Example 1 is lower than that of the fillers in other examples, which prevents the temperature of the organic matter entering from rising too fast during the pyrolysis process, thus preventing the organic waste from volatilizing too fast. Figure 5 As shown, in the gasification reaction chamber, the rate of precipitation of small molecule alkanes in the organic solid waste in Example 1 is slower, so that the alkanes are fully reacted in the fluidized bed gasification reactor, reducing the generation of tar, polycyclic aromatic hydrocarbons and VOCS, thereby greatly reducing the generation of pollution and improving the final synthesis gas production rate; in particular, the quartz sand particle size of Example 2 is 160-180 μm, which is smaller than the quartz sand particle size of 180-250 μm in Example 3 and the quartz sand particle size of 250-320 μm in Example 4. Compared with Example 1, they crack biomass and urban domestic waste faster, resulting in excessive volatilization of organic waste, so the alkane in the cracking gas is higher.

[0076] like Figure 6 and Figure 7As shown in the figure, when porous alumina is used as a catalyst in the gasification reaction chamber, the concentration of monocyclic benzene series and PAHs in the flue gas is significantly reduced compared with other fillers. The results show that the reduction of the heat transfer coefficient of the fluidized bed material reduces the heat transfer rate between the bed material and the organic solid waste, reduces the precipitation rate of volatiles in the organic solid waste, and thus reduces the concentration of PAHs precursors, i.e. small molecular hydrocarbons, in the flue gas, thereby inhibiting the formation of PAHs. Figure 4 The heat transfer coefficient is 540W / m 2 K of 250 ~ 320μm quartz sand, alternative heat transfer coefficient 730W / m 2 When the bed material is 160~180μm quartz sand of K, Figure 7 It can be seen that the total concentration of PAHs in the flue gas at the outlet of the fluidized bed of the gasification reaction chamber is reduced, and the total concentration of PAHs in the 250-320μm quartz sand bed material is reduced by 32.9% compared with the 160-180μm quartz sand. Further, when solid alumina with similar heat transfer coefficient and specific surface area is used to replace 250-320μm quartz sand as bed material, the total concentration of PAHs in the flue gas at the outlet of the fluidized bed of the gasification reaction chamber is reduced again, and the total concentration of PAHs in the solid alumina bed material is reduced by 29.2% compared with the 250-320μm quartz sand bed material. When porous alumina with similar heat transfer coefficient and the same crystal structure is used to replace solid alumina as bed material, the total concentration of PAHs in the flue gas at the outlet of the fluidized bed of the gasification reaction chamber is further reduced, and the total concentration of PAHs in the porous alumina catalyst is reduced by 20.9% compared with the solid alumina catalyst bed material. In addition, the capillary adsorption effect of porous alumina bed reduces the precipitation rate of PAHs precursors in flue gas, promotes the oxidation of PAHs precursors, and reduces the concentration of PAHs precursors and PAHs in flue gas. Figure 8 As shown, Example 1 compared with Example 3 pyrolysis biomass ( Figure 8 left side) and municipal solid waste ( Figure 8 The toxic equivalent concentration (TEQ conc) of polycyclic aromatic hydrocarbons (PAHs) in the gas composition when the spherical porous Al2O3 is used as a catalyst is also significantly reduced. On the one hand, the lower thermal conductivity of the spherical porous Al2O3 prevents the organic solid waste from heating up too quickly, thus preventing the organic waste from volatilizing too quickly, allowing the small molecule alkanes to fully react in the fluidized bed gasification reactor, reducing the production of tar and VOCS. On the other hand, the spherical porous Al2O3 has adsorption properties and can adsorb organic matter. The particle temperature distribution in the gasification reaction chamber 2 is shown in FIG. Fig.15 As shown, the particle temperature distribution is uniform.

[0077] The brick-shaped Al-based Ni-Mg catalyst in Example 1 was prepared in the following manner:

[0078] Step 1: The Al2O3 carrier is pretreated before use. The spherical activated alumina is crushed into powder in a pulverizer and then placed in a muffle furnace and calcined at 900°C for 15 hours.

[0079] Step 2, weigh a certain amount of pretreated Al2O3 powder, dissolve a certain amount of Mg(NO3)2·6H2O in deionized water, add Al2O3 powder while stirring, and impregnate at 60°C for 6 hours, dry the impregnation solution in a 110°C oven until the water is evaporated, cool it and place it in a muffle furnace for calcination at 850°C for 15 hours, and crush it to obtain a catalyst carrier. In this embodiment, the mass percentage of MgO in the carrier is adjusted to 10%.

[0080] Step 3, weigh a certain amount of the above catalyst carrier powder, dissolve a certain amount of Ni(NO3)2·6H2O in deionized water, add the catalyst carrier powder while heating, and immerse for 6 hours at a constant temperature of 60°C with stirring, dry the impregnation solution in an oven at 110°C until the water is evaporated, grind to powder after cooling, press tablets, calcine in a muffle furnace, and grind to a particle size of 0.25-0.42nm. The mass percentage of NiO in the carrier is controlled to be 18%.

[0081] In this embodiment, the catalyst prepared is a catalyst with nickel as the active component and Mg / Al as the mixed carrier. 10 -Al2O3.

[0082] Example 6

[0083] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the brick-shaped Al-based Ni-Mg catalyst is prepared in the following manner.

[0084] Step 1: The Al2O3 carrier is pretreated before use. The small spherical activated alumina is crushed into powder in a pulverizer and then placed in a muffle furnace and calcined at 900°C for 15 hours.

[0085] Step 2, weigh a certain amount of the above-mentioned pretreated Al2O3 powder, dissolve a certain amount of Ni(NO3)2·6H2O in deionized water, add the pretreated Al2O3 powder while heating, stir and impregnate for 6 hours at 60°C constant temperature, dry the impregnation solution in an oven at 110°C until the water is evaporated, grind it into powder after cooling, press it into tablets, calcine it in a muffle furnace, and grind it into paper particles with a particle size of 0.25-0.42nm. The mass percentage of NiO in the carrier is controlled to be 18%.

[0086] In this embodiment, the mass percentage of MgO in the carrier is adjusted to 0, that is, a catalyst with nickel as the active component, Ni / M0-Al2O3, is directly synthesized.

[0087] Example 7

[0088] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the brick-shaped Al-based Ni-Mg catalyst is prepared in the following manner.

[0089] Step 1: The Al2O3 carrier is pretreated before use. The spherical activated alumina is crushed into powder in a pulverizer and then placed in a muffle furnace and calcined at 900°C for 15 hours.

[0090] Step 2, weigh a certain amount of pretreated Al2O3 powder, dissolve a certain amount of Mg(NO3)2·6H2O in deionized water, add Al2O3 powder while stirring, and impregnate at 60°C for 6 hours, dry the impregnation solution in a 110°C oven until the water is evaporated, cool it and place it in a muffle furnace for calcination at 850°C for 15 hours, and crush it to obtain a catalyst carrier. In this embodiment, the mass percentage of MgO in the carrier is adjusted to 5%.

[0091] Step 3, weigh a certain amount of the above catalyst carrier powder, dissolve a certain amount of Ni(NO3)2·6H2O in deionized water, add the catalyst carrier powder while heating, and immerse for 6 hours at a constant temperature of 60°C with stirring, dry the impregnation solution in an oven at 110°C until the water is evaporated, grind to powder after cooling, press tablets, calcine in a muffle furnace, and grind to a particle size of 0.25-0.42nm. The mass percentage of NiO in the carrier is controlled to be 18%.

[0092] In this embodiment, a catalyst Ni / M5-Al2O3 is prepared, which uses nickel as an active component and Mg / Al as a mixed carrier.

[0093] Example 8

[0094] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the brick-shaped Al-based Ni-Mg catalyst is prepared in the following manner.

[0095] Step 1: The Al2O3 carrier is pretreated before use. The spherical activated alumina is crushed into powder in a pulverizer and then placed in a muffle furnace and calcined at 900°C for 15 hours.

[0096] Step 2, weigh a certain amount of pretreated Al2O3 powder, dissolve a certain amount of Mg(NO3)2·6H2O in deionized water, add Al2O3 powder while stirring, and impregnate at 60°C for 6 hours, dry the impregnation solution in a 110°C oven until the water is evaporated, calcine in a muffle furnace at 850°C for 15 hours after cooling, and obtain the catalyst carrier after crushing. In this embodiment, the mass percentage of MgO in the carrier is adjusted to 20%.

[0097] Step 3, weigh a certain amount of the above catalyst carrier powder, dissolve a certain amount of Ni(NO3)2·6H2O in deionized water, add the catalyst carrier powder while heating, and immerse for 6 hours at a constant temperature of 60°C with stirring, dry the impregnation solution in an oven at 110°C until the water is evaporated, grind it into powder after cooling, press the tablets into a muffle furnace for calcination, and then grind it into a particle size of 0.25-0.42nm. The mass percentage of NiO in the carrier is controlled to be 18%.

[0098] In this embodiment, the catalyst prepared is a catalyst with nickel as the active component and Mg / Al as the mixed carrier. 20 -Al2O3.

[0099] Example 9

[0100] The process of pyrolysis, gasification and reforming of biomass and municipal solid waste is the same as that of Example 1, except that the brick-shaped Al-based Ni-Mg catalyst is prepared in the following manner.

[0101] Step 1: The Al2O3 carrier is pretreated before use. The spherical activated alumina is crushed into powder in a pulverizer and then placed in a muffle furnace and calcined at 900°C for 15 hours.

[0102] Step 2, weigh a certain amount of pretreated Al2O3 powder, dissolve a certain amount of Mg(NO3)2·6H2O in deionized water, add Al2O3 powder while stirring, and impregnate at 60°C for 6 hours, dry the impregnation solution in a 110°C oven until the water is evaporated, calcine in a muffle furnace at 850°C for 15 hours after cooling, and obtain a catalyst carrier after crushing. In this embodiment, the mass percentage of MgO in the carrier is adjusted to 30%.

[0103] Step 3, weigh a certain amount of the above catalyst carrier powder, dissolve a certain amount of Ni(NO3)2·6H2O in deionized water, add the catalyst carrier powder while heating, and immerse for 6 hours at a constant temperature of 60°C with stirring, dry the impregnation solution in an oven at 110°C until the water is evaporated, grind to powder after cooling, press tablets, calcine in a muffle furnace, and grind to a particle size of 0.25-0.42nm. The mass percentage of NiO in the carrier is controlled to be 18%.

[0104] In this embodiment, the catalyst prepared is a catalyst with nickel as the active component and Mg / Al as the mixed carrier. 30 -Al2O3.

[0105] The BET specific surface area and pore structure test of the catalyst prepared in each of the above embodiments was carried out using the ASAP2405 specific surface measuring instrument produced by Micromeritics, USA. The adsorption test was carried out using N2 at a constant temperature of 77K. Before adsorption, the sample was evacuated at 120°C and 350°C for 1h and 2h respectively. The specific surface area was obtained by combining the BET equation with the N2 adsorption isotherm. It is shown in Table 2 below.

[0106] Table 2 Physical property parameters of Ni-Mg-Al system after reduction

[0107]

[0108] a Calculated using the BET equation; b Calculated using the BJH method when P / P0=0.99; c Calculated using the BJH method during the desorption stage; d Calculated based on the XRD spectrum of the reduced catalyst and the Scherrer formula.

[0109] Table 3 Comparison of basic strength of Ni-Mg-Al catalyst after reduction

[0110]

[0111] aThe total basicity of NM0A catalyst is taken as 1.00.

[0112] Depend on Fig. 9 and Fig.10 It can be seen that when the catalyst calcination temperature is 850℃, NM5A and NM 10 The phase composition of Ni, Mg and Al in A is Ni-MgO-Al2O3-MgAl2O4-NiAl2O4, while NM 20 A and NM 30 The composition of phase A is Ni-MgO-Al2O3-MgAl2O4-NiAl2O4-MgNiO2.

[0113] As shown in Table 2, all catalysts in the Ni-Mg-Al system are mesoporous materials. The surface area of ​​Al2O3 decreases due to the addition of MgO, but as the percentage of MgO increases, the specific surface area of ​​the composite catalyst increases, especially when the mass percentage of MgO is 10%, the specific surface area is the largest, and the Ni metal particle size is the smallest and the dispersion is the most uniform. As shown in Table 3, among which NM 10 Catalyst A has the most basic centers and the strongest basicity.

[0114] like Fig.11 and Fig.12 It can be seen that with the increase of MgO percentage, the amount of hydrogen consumed in the reduction process also increases, and the temperature of carbon dioxide desorption also increases. 10 A corresponds to a narrower desorption peak, indicating that the adsorption center distribution of the catalyst is relatively uniform.

[0115] like Fig.13 The figure shows the NM after restoration. 10 TEM (transmission electron microscopy) characterization results of catalyst A, NM 10 Catalyst A is spherical in shape and has a particle size of 5-7 nm. In the EDS elemental analysis, it can be seen that the active component Ni and the auxiliary agent MgO are uniformly dispersed on the surface of the carrier Al2O3.

[0116] like Fig.14 As shown in the stability test of 750℃ high temperature reaction for 60h, it was found that NM0A catalyst had the worst stability and activity, and the CO2 and CH4 conversion rates were only about 40% at the end of the reaction. When the MgO doping amount was 10mol%, the catalytic performance was the best, and the CO2 and CH4 conversion rates were the highest and both remained at about 85%.

[0117] The conversion rate of reactants of the composite catalyst containing Mg remained basically unchanged in the 60h stability test. After the reaction, the specific surface area of ​​the catalyst only decreased slightly, the particle size of the Ni metal particles in the active center only increased slightly, and the amount of carbon on the surface was also very small. This is mainly due to the addition of 10% MgO additive, which, on the one hand, enhances the thermal stability of the catalyst and strengthens the interaction between the metal and the carrier (Metal-Support Interaction, MSI). Strong MSI will have an "anchoring" effect on the active metal particles, limiting the migration and aggregation of metal particles. The active center Ni metal is less likely to migrate and sinter, inhibiting the sintering and carbon deposition of the catalyst. On the other hand, NM 10 Catalyst A has the most basic center numbers and the strongest basicity. The more basic sites on the catalyst surface, the stronger its ability to adsorb, activate and catalyze CO2, and produce more oxygen species, resulting in less carbon deposits and better catalytic performance.

Claims

1. A device for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming, characterized in that: The device comprises a gasification reaction chamber (2), a multi-stage high-temperature ventilation dust collector (6) and a reforming reaction chamber (9) which are connected in sequence. The top outlet of the gasification reaction chamber (2) is connected to the top inlet of the reforming reaction chamber (9) through a connecting pipe (7). The multi-stage high-temperature ventilation dust collector (6) is installed on the connecting pipe (7). A metal nozzle (5) is arranged directly below the bottom of the gasification reaction chamber (2). A first feed port (3) and a second feed port (4) are arranged on both sides of the metal nozzle (5). The gasification medium is fed from the first feed port (3) to the reforming reaction chamber (9). ) enters, pretreated organic solid waste particles enter from the second feed inlet (4), and hydrogen-rich fuel gas is sprayed upward from the metal nozzle (5) into the gasification reaction chamber (2); a gas outlet (10) is provided at the bottom of the reforming reaction chamber (9), the gas outlet (10) is connected to an induced draft fan (101), and the outlet end of the induced draft fan (101) is connected to the metal nozzle (5) through a pipeline, the gasification reaction chamber (2) is filled with a spherical porous Al2O3 catalyst, and the reforming reaction chamber (9) is filled with a brick-type Ni-Mg / Al2O3 catalyst.

2. The device for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 1 is characterized in that: The inner lining of the device is made of high temperature resistant material which is installed in an integrated manner.

3. The device for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 1 is characterized in that: The first feed port (3) of the gasification reaction chamber (2) is also connected to a fan (201), and a flow valve 1 (202) and a flow meter 1 (203) are sequentially arranged between the outlet of the fan (201) and the first feed port (3); and a flow valve 2 (102) and a flow meter 2 (103) are sequentially arranged between the gas outlet (10) and the fan (101).

4. The device for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 1 is characterized in that: A temperature sensor probe and a pressure sensor probe are installed in the gasification reaction chamber (2) and the reforming reaction chamber (9).

5. The method for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 1, characterized in that: The heat transfer coefficient of the porous alumina is 480W / m 2 K, specific surface area is 277.94m 2 / g, the porous alumina has pores of different sizes, and the number percentage distribution of pores of different sizes is as follows: <6nm 17.31% 6~8nm 16.09% 8~10nm 12.07% 10~12nm 16.08% 12~16nm 18.35% 16~20nm 14.06% 20~80nm 5.89% >80nm 0.16%.

6. A method for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming, using the device as claimed in any one of claims 1 to 4, characterized in that: The temperature of the gasification reaction chamber is controlled in the range of 650-800°C, and the volume flow ratio of the spherical porous Al2O3 filled in the gasification reaction chamber (2) to the volume flow rate of the gasification medium is 3000-5000h -1 The temperature of the reforming reaction chamber is controlled in the range of 700-850°C, and the volume / gas volume flow ratio of the brick-shaped Ni-Mg / Al2O3 catalyst filled in the reforming reaction chamber (9) is 5000-10000h -1 The gas velocity range of the gasification medium entering the gasification reaction chamber is 1.0 to 3.0 m / s.

7. The method for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 6, characterized in that: The solid waste includes one or more of domestic garbage and organic waste.

8. The method for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 6, characterized in that: The gasification medium is one or more mixtures of air, oxygen or water vapor.

9. The method for efficiently treating organic solid waste to produce hydrogen-rich fuel gas by integrating catalytic fluidized gasification and reforming according to claim 6, characterized in that: The organic solid waste is treated in a gasification reaction chamber and a reforming reaction chamber to obtain products with a distribution of 35-50% hydrogen, 25-40% CO, 5-10% methane and 1-3% ethylene.

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