Detailed Description
The biomass pyrolysis and catalytic cracking coupled reactor apparatus of the present application is described in further detail below. And do not limit the scope of the present application, which is defined by the claims. Certain disclosed specific details provide a thorough understanding of various disclosed embodiments. One skilled in the relevant art will recognize, however, that embodiments may be practiced without one or more of the specific details, with other materials, etc.
Unless the context requires otherwise, in the description and claims, the terms "comprise," comprises, "and" comprising "are to be construed in an open-ended, inclusive sense, i.e., as" including, but not limited to.
Reference in the specification to "an embodiment," "another embodiment," or "certain embodiments," etc., means that a particular described feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, "an embodiment," "another embodiment," or "certain embodiments" do not necessarily all refer to the same embodiments. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Each feature disclosed in this specification may be replaced by an alternative feature serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, the features disclosed are merely generic examples of equivalent or similar features.
The term "catalytic cracking riser reactor" is a riser in which petroleum fractions undergo catalytic cracking reactions; the 'upgrading riser reactor' is a riser for further carrying out catalytic cracking upgrading on pyrolysis oil after biomass fuel pyrolysis to obtain small molecular fuel.
The catalytic cracking process in petroleum processing is a process of changing heavy oil macromolecules into small molecules such as liquefied gas, gasoline, diesel oil and the like under the action of a catalyst. When the gasoline and diesel oil are produced by the heavy oil through the lightening process, the generated coke is attached to the catalyst, the activity of the catalyst can be recovered only through coke burning, and a large amount of heat generated by the coke burning cannot be fully utilized, so that the resource waste is caused. Therefore, a large amount of heat generated by the burning of the catalytic cracking device can be used for the pyrolysis reaction of biomass, and meanwhile, the biomass pyrolysis oil is modified under the action of the catalytic cracking catalyst, but the characteristics of high aromatic hydrocarbon and easy coking of the biomass pyrolysis oil are easy to generate competitive adsorption with petroleum fractions in the catalytic cracking process, so that the conversion rate and the product distribution of the petroleum fractions are influenced. The biomass pyrolysis is coupled with the catalytic cracking of petroleum fractions, so that the self-sufficiency of heat in the biomass pyrolysis process is realized, the quality improvement of biomass pyrolysis oil is realized through catalytic modification, the product distribution and the product quality deterioration caused by competitive adsorption are avoided by using the double lifting pipes, and the fuel meeting the use requirement is produced.
The application is further described as follows:
in one aspect, an apparatus for coupling biomass pyrolysis with fluidized catalytic cracking reaction includes a biomass pyrolysis reactor, a catalyst regenerator, and a catalytic cracking reaction apparatus, wherein the biomass pyrolysis reactor is disposed inside the catalyst regenerator.
In the application, the biomass pyrolysis reactor is arranged in the catalyst regenerator, and the pyrolysis reaction is carried out by utilizing the heat transferred in the catalyst regenerator. The pyrolysis oil after the pyrolysis reaction further enters a catalytic cracking reaction device for further modification into a required product. In the coupling device, the heat of the catalyst regenerator can be utilized, a heat source required by pyrolysis reaction in the prior art is omitted, the abrasion to equipment is increased due to the addition of the heat source in the prior art, and an energy-saving effect is also achieved.
The catalyst regenerator of the present application includes all of the structures disclosed in the prior art. Such as: the catalytic regenerator is a reducing tank body, the diameter of the upper part of the tank body is larger than that of the lower part of the tank body, namely, the upper part of the tank body is a dilute phase section, and the lower part of the tank body is a dense phase section.
At least two groups of cyclone separators are arranged in the dilute phase section, wherein one group of cyclone separators is connected with the upper end part of the biomass pyrolysis reactor. Pyrolysis gas generated by the biomass pyrolysis reaction and biochar pass through a cyclone separator, and then the biochar enters a catalyst regenerator again to be combusted to release energy; the separated pyrolysis gas is separated into pyrolysis oil and non-condensable gas again through the condensed pyrolysis product.
In certain embodiments, the biomass pyrolyzer is a cylindrical straight tube into which the biomass pyrolyzer extends through the bottom of the catalyst regenerator.
The ratio of the pipe diameter of the biomass pyrolyzer to the pipe diameter of the dense-phase section of the catalyst regenerator is 0.1:1-0.5: 1.
In the dense phase section (dense phase bed) of the catalytic regenerator, the pyrolysis reactor is directly buried in the catalyst, the heat transfer efficiency is higher than that of the dilute phase section, the temperature drop caused by rapid temperature rise and severe heat desorption when biomass just enters the pyrolysis reactor can be reduced, and the whole reaction can be controlled under the isothermal condition.
In some embodiments, the inlet ends of the cyclones in the dilute phase section are in communication with the dilute phase section and the outlet ends are in communication with the environment.
In certain embodiments, the catalysts of the present application include, but are not limited to, catalysts used in catalytic cracking reactions in the petrochemical field. Such as molecular sieve catalysts, metal oxide based catalysts.
In certain embodiments, the catalyst regenerator is connected to the catalytic cracking reactor by a catalyst regeneration ramp and a catalyst regeneration ramp.
The catalytic cracking reactor of the present application is all catalytic cracking reaction units of the prior art. Such as a two-stage riser reactor.
In certain embodiments, the catalytic cracking reaction apparatus comprises a two-stage riser reactor, i.e., a catalytic cracking riser reactor and an upgrading riser reactor.
In certain embodiments, the pyrolysis oil produced by the pyrolysis reaction of the biomass enters the upgrading riser to further carry out the upgrading reaction.
The catalytic cracking process in petroleum processing is a process of changing heavy oil macromolecules into small molecules such as liquefied gas, gasoline, diesel oil and the like under the action of a catalyst. When the gasoline and diesel oil are produced by the heavy oil through the lightening process, the generated coke is attached to the catalyst, the activity of the catalyst can be recovered only through coke burning, and a large amount of heat generated by the coke burning cannot be fully utilized, so that the resource waste is caused. Therefore, a large amount of heat generated by the coke burning of the catalytic cracking unit is used for the pyrolysis reaction of the biomass, and meanwhile, the biomass pyrolysis oil is upgraded through the action of the catalytic cracking catalyst. Through the coupling use of the biomass pyrolyzer and the two-section riser reactor, the pyrolysis oil is introduced into the modified riser reactor, so that competitive adsorption of the biomass pyrolysis oil and the petroleum fraction in the catalytic cracking process can be better avoided, and the conversion rate and the product distribution of the petroleum fraction are further improved.
In the present application, the biomass includes but is not limited to cellulose and lignin agricultural and forestry waste.
The method can fully utilize the existing petroleum fraction catalytic cracking device, adopts a double-riser catalytic cracking reactor, one riser carries out catalytic cracking modification on the biomass pyrolysis oil, and the other riser carries out catalytic cracking on the petroleum fraction, so that the scale of the single biomass pyrolysis oil modification device can be improved through the catalytic cracking of the petroleum fraction, and the influence on the operation and the economic benefit of the device due to the too small scale of the single biomass pyrolysis oil modification device can be avoided. Meanwhile, the two risers are separately subjected to catalytic cracking reaction, so that competitive adsorption of biomass pyrolysis oil and petroleum fractions can be avoided, and the two reactors can determine appropriate reaction conditions according to the reaction rules of different fractions. Reaction products of the modification riser and the cracking riser enter the same fractionating tower to be separated, so that the instability of the products after the biomass pyrolysis oil reaction is relieved.
In another aspect, a method of biomass pyrolysis coupled with fluidized catalytic cracking, comprising:
catalytically reacting catalytically cracked material oil in a catalytic cracking reaction device, separating reacted oil gas and spent catalyst through a cyclone separator, feeding the spent catalyst into a catalyst regenerator for combustion, and separating the oil gas in a fractionating tower;
the biomass raw material enters a biomass pyrolysis reactor for pyrolysis reaction, and the biomass pyrolysis reactor is arranged in a catalyst regenerator;
and the pyrolysis oil obtained after the biomass pyrolysis reaction enters a catalytic cracking reaction device for catalytic reaction.
And condensing the products after the biomass pyrolysis reaction to obtain pyrolysis oil and non-condensable gas, wherein the non-condensable gas enters the biomass pyrolysis reactor. The non-condensable gas is used as stripping gas of biomass pyrolysis reaction.
The fraction separated from the oil gas in the fractionating tower comprises: cracked gas, gasoline, diesel oil, recycle oil, slurry oil and the like. The recycle oil can be returned to the catalytic cracking reaction device again for catalytic reaction.
In certain embodiments, the catalytically cracked feedstock oil is heat exchanged with the pyrolysis products prior to being passed to the catalytic cracking reactor. The heat in the pyrolysis reaction and the catalytic cracking reaction process is recycled as much as possible, so that the effect of energy conservation can be achieved.
In certain embodiments, the catalytic cracking reaction apparatus includes a cracking riser reactor and an upgrading riser reactor, the catalytic cracking feedstock or/and recycle oil enters the cracking riser reactor for reaction, and the pyrolysis oil after the biomass pyrolysis reaction enters the upgrading riser reactor for reaction.
In some embodiments, the regeneration reaction occurs in the catalyst regenerator at a temperature of 600-720 ℃.
High-temperature regenerant and flue gas generated by the regeneration reaction of the catalyst provide reaction heat for biomass pyrolysis.
In some embodiments, the outlet temperature of the biomass pyrolysis reactor is 500 to 650 ℃ and the reaction pressure is 0.1 to 0.4 MPa.
In some embodiments, the time for the pyrolysis reaction of the biomass is 0.5 to 30 seconds.
In some embodiments, the outlet temperature of the upgrading lift reactor is 450-600 ℃ and the reaction time is 1-4 s. The reaction pressure is 0.1-0.4 MPa.
In some embodiments, the outlet temperature of the cracking riser reactor is 450-550 ℃, the reaction time is 1-3s, and the reaction pressure is 0.1-0.4 MPa.
In some embodiments, the pyrolysis gas separated from the biomass pyrolysis product is condensed, and the condensation process can adopt air cooling, water cooling or other condensation modes, wherein the final condensation temperature is 40-80 ℃ and the normal pressure is realized.
Through the coupling of the biomass pyrolysis reaction with the catalytic cracking reaction of the present application, advantages thereof include:
(1) the heat of the biomass pyrolysis process is derived from the heat in the catalyst regenerator, a heat carrier is not needed, the abrasion of the heat carrier to the reactor is reduced, and meanwhile, the separation of a reaction product and the heat carrier is also reduced. In addition, the biochar generated in the biomass pyrolysis process and the coke generated in the catalytic cracking process are combusted to supply heat, so that the heat generated by burning the spent catalyst is fully utilized, and the energy consumption is reduced.
(2) The process provided by the application realizes the one-time generation of high-quality bio-gasoline and diesel oil by biomass, and the pyrolysis reactor and the catalytic cracking reactor can flexibly change the operation conditions. By adopting the technical process of catalytic cracking of petroleum fractions, the scale effect of the device can be fully utilized, the influence of unstable supply of biomass raw materials can be relieved, and the production cost can be reduced.
(3) Particularly, the biomass pyrolyzer is coupled with the catalytic cracking devices of the two sections of riser reactors, the cracking riser performs catalytic cracking reaction on the fresh raw materials, and the upgrading riser performs catalytic cracking on pyrolysis oil and recycle oil, so that the influence of the pyrolysis oil on the catalytic cracking of the fresh raw materials can be avoided, and the independent control of the catalytic cracking of the fresh raw materials and the upgrading of the biomass pyrolysis oil can be realized.
The following examples are intended to further illustrate the invention only and are not intended to limit the scope of the invention.
Example 1
Referring to FIG. 1, this example is a reactor unit with a biomass pyrolyzer coupled to a catalytic cracking reactor unit of a two-stage riser generator. The catalytic cracking reaction device comprises two sections of riser reactors and a catalytic cracking reaction settler II, wherein the two sections of riser reactors are respectively a catalytic cracking riser reactor I' and an upgrading riser reactor I.
As shown in fig. 1, the biomass pyrolysis reactor III is disposed in the catalyst regenerator IV through the bottom of the catalyst regenerator, the pyrolysis reactor III is a cylindrical straight pipe, and the upper end of the pyrolysis reactor III is located at the upper portion in the catalyst regenerator IV. The catalyst regenerator IV is respectively connected with the cracking riser reactor I' and the upgrading riser reactor I.
The upper end of the biomass pyrolysis reactor III is connected with a cyclone separator 14, and pyrolysis gas in biomass pyrolysis products is separated from coke in the cyclone separator. The top outlet of the cyclone separator is connected with a condenser VII, and the pyrolysis gas enters the condenser VII to be condensed. And the condenser VII is connected with the oil-gas separation tank VI, the condensed pyrolysis product is separated in the oil-gas separation tank VI and is separated into uncondensed non-condensable gas and pyrolysis oil, the non-condensable gas is used as pre-lifting gas 3 and enters the biomass pyrolysis reactor III, and the pyrolysis oil 4 enters the upgrading riser reactor I to further carry out catalytic upgrading reaction according to the requirement.
The catalytic cracking settler is connected with a catalyst regenerator IV through a catalyst spent inclined tube 15, and spent catalyst in the settler is sent into the regenerator for regeneration. The catalyst regenerator IV is connected with the cracking riser reactor I 'and the upgrading riser reactor I through catalyst regeneration inclined pipes (16, 16'). The catalytic cracking reaction device can be used for all petrochemical catalytic reactions in the prior art, and the pyrolysis oil can be mixed with raw materials used for modification reaction thereof or only the pyrolysis oil enters the upgrading riser reactor I for catalytic cracking reaction.
A cyclone separator is arranged in the catalytic cracking reaction settler II. The upper end parts of the catalytic cracking riser reactor I' and the upgrading riser reactor I are respectively connected with a cyclone separator, oil gas is separated from the catalyst by the cyclone separator, and the separated spent catalyst enters a catalyst regenerator III through a catalyst spent inclined tube 15 for combustion regeneration. The top of the catalytic cracking reaction settler II is connected with a fractionating tower V, oil gas obtained after the modification reaction enters the fractionating tower V to further separate corresponding components and recycle oil 13, and the recycle oil can further return to the modification reactor I for the modification reaction.
The process flow of the device for coupling biomass pyrolysis and catalytic cracking comprises the following steps:
the dried and crushed biomass raw material 1 enters the bottom of the biomass pyrolysis reactor III through a feeder, and the pyrolysis noncondensable gas 3 introduced from the bottom of the pyrolysis reactor III is fluidized and lifted to enter the inside of the pyrolysis reactor III. And carrying out pyrolysis reaction under the heating of a high-temperature catalyst and flue gas in a catalyst regenerator IV to generate pyrolysis gas and biochar, wherein the outlet temperature of the biomass pyrolysis reactor is 500-650 ℃, the reaction pressure is 0.1-0.4MPa, and the time of the biomass pyrolysis reaction is 0.5-3 s. The temperature in the catalyst regenerator IV under normal pressure is 600-720 ℃. And transferring heat to the biomass pyrolysis reactor by using the catalyst and the flue gas in the catalyst regenerator to allow the biomass to carry out pyrolysis reaction.
After pyrolysis oil gas 2 and biochar flowing out of the top of the pyrolysis reactor III are separated by the cyclone separator, the biochar enters the catalytic regenerator IV to be combusted to release heat, and the spent catalyst is regenerated by combining with newly added fuel 6. And the pyrolysis oil gas is condensed by a condenser VII and then enters an oil-gas separation tank VI to be separated into pyrolysis oil 4 and non-condensable gas 3. The non-condensable gas enters the bottom of the biomass pyrolysis reactor III to be used as fluidizing gas, the pyrolysis oil 4 enters the upgrading riser reactor I, and the pyrolysis oil and the regenerated catalyst are subjected to contact reaction and move upwards under the action of the pre-stripping gas 7, wherein the outlet temperature of the upgrading riser reactor is 450-fold, the reaction time is 1-4s, and the reaction pressure is 0.1-0.4 MPa. Fresh catalytic cracking raw material 5 enters a cracking riser reactor I' after heat exchange with pyrolysis gas in a condenser VII, and then enters a recycle oil 13 fraction separated from a fractionating tower to contact with a regenerated catalyst for catalytic cracking reaction, wherein the outlet temperature of the cracking riser reactor is 450-550 ℃, the reaction time is 1-3s, and the reaction pressure is 0.1-0.4 MPa. The reaction substance entering the catalytic cracking riser I' can be one of fresh catalytic cracking raw material, recycle oil fraction or the combination of the two according to the actual situation.
At the outlet of the catalytic cracking reaction device, reaction oil gas and a coking catalyst are separated by a cyclone separator, the coking spent catalyst enters a stripping section of a settler II for stripping so as to desorb adsorbed oil gas and reduce the coke yield, and the stripped spent catalyst enters a catalyst regenerator IV for coking regeneration through a catalyst spent inclined tube 15; the reaction oil gas 9 enters a fractionating tower V for further separation into cracked gas 10, gasoline 11(<200 ℃), diesel 12 (200-. The recycle oil returns to the cracking riser to carry out secondary conversion.
Experimental example 1:
the experimental example employed a reaction apparatus in which the biomass pyrolyzer of example 1 was coupled to a catalytic cracking reaction apparatus of a two-stage riser generator. Pine sawdust was used as a raw material, a fluidized bed type pyrolysis reactor was fixed, fluidizing gas was nitrogen, biomass pyrolysis reaction time was 20 seconds, and distribution of the obtained product and properties of pyrolysis oil were as shown in tables 1 and 2.
TABLE 1 pyrolysis product distribution
TABLE 2 pyrolysis oil properties
And carrying out catalytic cracking modification on the Pyrolysis Oil (PO) obtained at the reaction temperature of 510 ℃, wherein a fixed fluidized bed reactor is adopted as a modified riser reactor, and the reaction temperature of the pyrolysis oil catalytic cracking is 500 ℃. The catalytic cracking riser reactor is internally used for carrying out catalytic cracking reaction by taking vacuum wax oil of petroleum fraction as a raw material, and the reaction temperature is 500 ℃. Two industrial catalytic cracking equilibrium agents which take USY and ZSM-5 as active components are respectively adopted as catalysts, and the weight hourly space velocity is 15h-1The vacuum wax oil properties are shown in Table 3, and the product distribution is shown in Table 4.
TABLE 3 basic Properties of certain vacuum wax oils
TABLE 4 Bio-oil upgrading and Petroleum fraction catalytic cracking product distribution