CN108611115B

CN108611115B - Liquefaction equipment and method for biomass liquefaction

Info

Publication number: CN108611115B
Application number: CN201810547386.6A
Authority: CN
Inventors: 耿一博
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-05-31
Filing date: 2018-05-31
Publication date: 2021-09-03
Anticipated expiration: 2038-05-31
Also published as: CN108611115A

Abstract

The invention discloses a liquefaction device and a method for biomass liquefaction, wherein a biomass slurrying heating furnace is communicated with a first reactor, one side of the first reactor is provided with a second reactor, the lower part of the second reactor is provided with a first material conveying pipe, the first reactor is communicated with the first material conveying pipe through a corresponding pipeline, the upper part of the second reactor is communicated with a high-temperature separator, the high-temperature separator is communicated with a reduced pressure distiller, the high-temperature separator is communicated with a feeding pipe of an online hydrogenation reactor through the second material conveying pipe, and the feeding pipe of the online hydrogenation reactor is communicated with a steam-oil separator. The self-produced oil product is used for heat conduction and swelling without using additional media such as heat conduction oil and the like, so that the production cost and the separation and recovery cost are reduced; the chemical stability of the biomass fuel is improved, the condensation of biomass pyrolysis free radical fragments is prevented, and the yield is improved; the calorific value of the oil product is improved, and the oil product can be directly used as diesel oil; the acidity of the oil product is reduced, and a large-scale industrialized device can be realized.

Description

Liquefaction equipment and method for biomass liquefaction

Technical Field

The invention relates to the field of agricultural straw treatment, in particular to liquefaction equipment and a method for biomass liquefaction.

Background

The straw is a general term of stem and leaf parts of mature crops, generally refers to the residual parts of wheat, rice, corn, potatoes, rape, cotton, sugarcane and other crops (generally coarse grain) after seeds are harvested, and the straw is rich in nitrogen, phosphorus, potassium, calcium, magnesium, organic matters and the like. At present, straws are generally burnt and the like, and the existing straw burning causes air pollution to the atmosphere and wastes energy.

As the technology is developed, the industrial treatment of the straws is started, in the prior art, the straws are treated by adopting water at high temperature and high pressure, the cost is high, the danger coefficient is high, the steps of adopting a plurality of reactors are complicated, or the inert gas of nitrogen is adopted as a carrier for cracking. The existing straw cracking process has the defects of high cost, large actual operation difficulty, large process route length investment and the like, and the straws are decomposed into free radical fragments which are easy to coke in the heating process of the preheater, so that the equipment is greatly damaged, and the service life of the equipment is shortened. Accordingly, the prior art is subject to further improvement and development.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention provides a liquefaction apparatus and method for biomass liquefaction, so as to reduce the production cost and the separation and recovery cost, and increase the calorific value of the oil product.

In order to solve the technical problem, the scheme of the invention comprises the following steps:

a liquefaction device for biomass liquefaction comprises a biomass slurrying heating furnace, wherein the biomass slurrying heating furnace is communicated with a first reactor, a second reactor is arranged on one side of the first reactor, a first material conveying pipe is arranged at the lower part of the second reactor, the first reactor is communicated with the first material conveying pipe through a corresponding pipeline, the upper part of the second reactor is communicated with a high-temperature separator, the high-temperature separator is communicated with a reduced-pressure distiller, the high-temperature separator is communicated with a feeding pipe of an online hydrogenation reactor through the second material conveying pipe, a third material conveying pipe is arranged at the upper end of the reduced-pressure distiller, the third material conveying pipe is communicated with the second material conveying pipe, the feeding pipe of the online hydrogenation reactor is communicated with a gasoline separator, and the gasoline separator is communicated with the upper part of the first reactor through a first heat exchanger; the online hydrogenation reactor is communicated with a medium-temperature separator through a second heat exchanger, the medium-temperature separator is communicated with a normal-temperature separator through a third heat exchanger, the normal-temperature separator is communicated with a main circulation compressor, the main circulation compressor is communicated with an auxiliary circulation compressor through a compression pipeline, the auxiliary circulation compressor is communicated with a biomass slurrying heating furnace through a circulation pipeline, a fourth material conveying pipe is arranged on the circulation pipeline, and the fourth material conveying pipe is communicated with the bottom of the first reactor; the compression pipeline is provided with a branch which is communicated with the hydrogen supply pump, and one side of the branch is communicated with the first material conveying pipe.

The liquefaction equipment, wherein, above-mentioned living beings slurrying heating furnace disposes feedway, feedway includes the blendor, the blendor is linked together with the dispersion agitator tank, the dispersion agitator tank is linked together through fifth conveying pipeline and first circulating pump, first circulating pump is linked together through sixth conveying pipeline and swelling agitator tank, the swelling agitator tank is linked together through seventh conveying pipeline and second circulating pump, the second circulating pump is linked together through eighth conveying pipeline and high-pressure pump, the high-pressure pump is linked together through corresponding pipeline and above-mentioned circulation pipeline.

The liquefaction equipment, wherein, the above-mentioned sixth conveying pipeline is linked together through the ninth conveying pipeline and the upper portion of dispersion agitator tank.

The liquefaction equipment, wherein, above-mentioned eighth conveying pipeline is linked together through the tenth conveying pipeline and the upper portion of swelling agitator tank.

The liquefaction equipment is characterized in that the mixer is provided with a biomass bin and a solvent tank, the biomass bin is used for providing biomass materials for the mixer, and the solvent tank is used for providing reaction solvent for the mixer.

The liquefaction equipment is characterized in that the medium temperature separator is communicated with the solvent tank through a corresponding pipeline.

The liquefaction equipment is characterized in that the first reactor and the second reactor are both circulating suspension bed reactors.

A method for directly liquefying biomass into fuel oil by using the liquefying device comprises the following steps:

crushing biomass, fully mixing the crushed biomass with superfine hydrated ferric oxide in a mixer, sequentially passing through a dispersion stirring tank and a swelling stirring tank, entering a biomass slurry heating furnace for preheating, sequentially passing through a first reactor and a second reactor under the conditions that the reaction temperature is 250-550 ℃ and the pressure is 10-150 Pa to obtain a crude product, sequentially treating the crude product through a high-temperature separator, a reduced-pressure distiller, an online hydrogenation reactor, a medium-temperature separator and a normal-temperature separator to obtain a water-containing substance with the water content of 35 percent and semi-finished oil, and recovering pyroligneous liquor from the water-containing substance with the water content of 35 percent, wherein the heat value of the semi-finished oil is equal to 75-80 percent of the heat value of diesel oil.

The method specifically comprises the following steps: the biomass is plant straw; the biomass liquefaction circulating solvent adopts coal tar to catalyze and prehydrogenation, and is prepared into material slurry with solid concentration of 20-30%; after ten cycles of the method, the coal tar can be replaced by the high-fraction still bottom oil generated by the process.

The invention provides liquefaction equipment and a method for biomass liquefaction, which do not use extra media such as heat conduction oil and the like, use part of self-produced oil products for heat conduction, and reduce the production cost and the separation and recovery cost; the chemical stability of the biomass fuel is improved, the condensation of biomass pyrolysis free radical fragments is prevented, and the yield is improved; the heat value of the oil product is improved, generally exceeds 40MJ/Kg, and the oil product can be directly used as diesel oil; the acidity of the oil product is reduced and can reach Ph 5-7; can realize large-scale industrialized devices, each set of equipment produces more than 10 tons of oil per hour, and the oil production efficiency is greatly improved.

Drawings

FIG. 1 is a schematic diagram of a liquefaction plant in accordance with the present invention.

Detailed Description

The invention provides a liquefaction device and a method for biomass liquefaction, and the invention is further described in detail below in order to make the purpose, technical scheme and effect of the invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a liquefaction device for biomass liquefaction, which is shown in figure 1 and comprises a biomass slurrying heating furnace 7, wherein, the biomass slurrying heating furnace 7 is communicated with the first reactor 9, one side of the first reactor 9 is provided with a second reactor 10, the lower part of the second reactor 10 is provided with a first material conveying pipe 21, the first reactor 10 is communicated with the first material conveying pipe 21 through a corresponding pipeline, the upper part of the second reactor 10 is communicated with a high temperature separator 13, the high temperature separator 13 is communicated with a reduced pressure distiller 14, the high temperature separator 13 is communicated with a feeding pipe of the on-line hydrogenation reactor 15 through a second material conveying pipe 22, the upper end of the reduced pressure distiller 14 is provided with a third material conveying pipe 23, the third material conveying pipe 23 is communicated with the second material conveying pipe 22, the feeding pipe of the on-line hydrogenation reactor 15 is communicated with a gasoline separator 12, and the gasoline separator 12 is communicated with the upper part of the first reactor 9 through a first heat exchanger 11; the online hydrogenation reactor 15 is communicated with the medium temperature separator 16 through a second heat exchanger 24, the medium temperature separator 16 is communicated with the normal temperature separator 17 through a third heat exchanger 25, the normal temperature separator 17 is communicated with the main circulation compressor 18, the main circulation compressor 18 is communicated with the auxiliary circulation compressor 8 through a compression pipeline 26, the auxiliary circulation compressor 8 is communicated with the biomass slurrying heating furnace 7 through a circulation pipeline 27, a fourth material conveying pipe 28 is arranged on the circulation pipeline 27, and the fourth material conveying pipe 28 is communicated with the bottom of the first reactor 9; the compression line 26 is provided with a branch 29, the branch 29 is connected to the hydrogen supply pump 20, and one side of the branch 29 is connected to the first feed pipe 21.

Further, the biomass slurry heating furnace 7 is provided with a feeding device, the feeding device includes a mixer 3, the mixer 3 is communicated with a dispersion stirring tank 4, the dispersion stirring tank 4 is communicated with a first circulating pump 5 through a fifth conveying pipe 30, the first circulating pump 5 is communicated with a swelling stirring tank 6 through a sixth conveying pipe 31, the swelling stirring tank 6 is communicated with a second circulating pump 33 through a seventh conveying pipe 32, the second circulating pump 33 is communicated with a high pressure pump 19 through an eighth conveying pipe 34, and the high pressure pump 19 is communicated with the circulating pipeline 27 through a corresponding pipeline.

In particular, the sixth feed pipe 31 is connected to the upper portion of the dispersion agitator tank 4 through a ninth feed pipe 35. The eighth feed passage 34 is connected to the upper portion of the swelling agitator tank 6 through a tenth feed passage 36. The mixer 3 is provided with a biomass bin 2 and a solvent tank 1, the biomass bin 2 is used for providing biomass materials for the mixer 3, and the solvent tank 1 is used for providing reaction solvents for the mixer 3. The medium temperature separator 16 is communicated with the solvent tank 1 through a corresponding pipeline, so that the solvent can be recycled, and the biomass preparation primary solvent is a hydrogen supply circulating solvent subjected to catalytic hydrogenation. The biomass liquefaction circulating solvent adopts coal tar (anthracene section) for catalytic prehydrogenation, has relatively stable solvent property and good slurrying property, and can be prepared into a biomass liquefaction circulating solvent with the solid concentration of 20-30%. The high-concentration biomass slurry with good fluidity is pre-hydrogenated by the material slurry and the circulating solvent, the hydrogen supply performance is obviously improved, the circulating solvent with strong hydrogen supply performance enables the biomass to be effectively prevented from condensing the thermally decomposed free radical fragments of the biomass in the heating process of the preheater, coking is prevented, the heating operation period is prolonged, the heat utilization rate is improved, and the hydrogen supply solvent can also improve the conversion rate and the oil yield of the biomass liquefaction process. After ten circulation operations, the high-fraction still bottom oil generated by the process can be used for replacing the anthracene segment of the coal tar, so that the biomass can be better thermally melted, the possibility of invasion of toxic substances of the coal tar is avoided, the production cost is reduced, and the yield is improved. The anthracene section coal tar (having solubility to hydrogen) and the cauldron bottom oil have good solubility (can fully react) to the biomass, have improved the yield of sudden strain of a muscle schizolysis greatly.

The first reactor 9 and the second reactor 10 are both circulating suspension bed reactors, and a forced circulating suspension bed reactor is adopted, because the inside of the forced circulating suspension bed reactor is in a fully-returning mixed flow mode, the axial temperature distribution of the biomass liquefaction reactor is uniform, the reaction temperature is easy to control, the reaction temperature can be controlled through the feeding temperature, the cold hydrogen production control of the side line of the reactor is not needed, the product property is stable, because the gas retention coefficient of the forced circulating suspension bed reactor is low, the utilization rate of the liquid phase of the reactor is high, the forced circulating suspension bed enables the inside of the reactor to obtain higher liquid velocity, the deposition of biomass ash and an additional catalyst in the reactor can be effectively prevented, the material temperature in the reactor is between 250 ℃ and 550 ℃, the pressure is between 15Pa and 150Pa, and different biomasses adopt different working conditions.

The invention also provides a method for directly liquefying biomass into fuel oil by using the liquefying equipment, which comprises the following steps:

crushing biomass, fully mixing the crushed biomass with superfine hydrated ferric oxide in a mixer 3, sequentially passing through a dispersing stirring tank 4 and a swelling stirring tank 6, entering a biomass slurry heating furnace 7 for preheating, sequentially passing through a first reactor 9 and a second reactor 10 under the conditions that the reaction temperature is 250-550 ℃ and the pressure is 10-150 Pa to obtain a crude product, sequentially passing through a high-temperature separator 13, a reduced-pressure distiller 14, an online hydrogenation reactor 15, a medium-temperature separator 16 and a normal-temperature separator 17 to obtain a water-containing substance with the water content of 35 percent and semi-finished oil, and recovering the wood vinegar liquid of the water-containing substance with the water content of 35 percent, wherein the heat value of the semi-finished oil is equal to 75-80 percent of that of diesel oil. And it specifically still includes: the biomass is plant straw; the biomass liquefaction circulating solvent adopts coal tar to catalyze and prehydrogenation, and is prepared into material slurry with solid concentration of 20-30%; after ten cycles of the method, the coal tar can be replaced by the high-fraction still bottom oil generated by the process.

And ultrafine hydrated iron oxide is prepared by taking ultrafine hydrated iron oxide as a liquefaction catalyst, divalent Fe as a raw material and partial liquefied oil as a carrier of the raw material straws. The catalyst has the characteristics of small particle size and high catalytic activity, and can directly liquefy biomass with low catalyst preparation cost and low addition amount and a relatively simple preparation process.

And the vacuum distillation is a mature and effective separation method for removing tar and solids, the distillate of the vacuum distillation hardly contains tar pitch and is a raw material for catalytic hydrogenation of a circulating solvent, and the residue of the vacuum distillation contains 5% of solids.

The circulating solvent and the biomass liquefaction primary product adopt forced circulation suspension hydrogenation. The suspension bed reactor can update the catalyst in the reactor at any time, the operation life of stable hydrogenation is prolonged, the risk of the fixed bed reaction caused by the increase of the carbon deposition pressure difference of the catalyst is avoided, the stable hydrogenation depth enables the product to have stable properties, and compared with the fixed bed, the suspension bed has more stable operability, longer operation period and wider raw material adaptability.

It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

Claims

1. A liquefaction device for biomass liquefaction comprises a biomass slurrying heating furnace and is characterized in that the biomass slurrying heating furnace is communicated with a first reactor, a second reactor is arranged on one side of the first reactor, a first material conveying pipe is arranged on the lower portion of the second reactor, the first reactor is communicated with the first material conveying pipe through a corresponding pipeline, the upper portion of the second reactor is communicated with a high-temperature separator, the high-temperature separator is communicated with a reduced-pressure distiller, the high-temperature separator is communicated with a feeding pipe of an online hydrogenation reactor through the second material conveying pipe, a third material conveying pipe is arranged at the upper end of the reduced-pressure distiller, the third material conveying pipe is communicated with the second material conveying pipe, the feeding pipe of the online hydrogenation reactor is communicated with a steam-oil separator, and the steam-oil separator is communicated with the upper portion of the first reactor through a first heat exchanger; the online hydrogenation reactor is communicated with a medium-temperature separator through a second heat exchanger, the medium-temperature separator is communicated with a normal-temperature separator through a third heat exchanger, the normal-temperature separator is communicated with a main circulation compressor, the main circulation compressor is communicated with an auxiliary circulation compressor through a compression pipeline, the auxiliary circulation compressor is communicated with a biomass slurrying heating furnace through a circulation pipeline, a fourth material conveying pipe is arranged on the circulation pipeline, and the fourth material conveying pipe is communicated with the bottom of the first reactor; a branch is arranged on the compression pipeline and is communicated with the hydrogen supply pump, and one side of the branch is communicated with the first material conveying pipe;

the biomass slurrying heating furnace is provided with a feeding device, the feeding device comprises a mixer, the mixer is communicated with a dispersing and stirring tank, the dispersing and stirring tank is communicated with a first circulating pump through a fifth conveying pipe, the first circulating pump is communicated with a swelling and stirring tank through a sixth conveying pipe, the swelling and stirring tank is communicated with a second circulating pump through a seventh conveying pipe, the second circulating pump is communicated with a high-pressure pump through an eighth conveying pipe, and the high-pressure pump is communicated with the circulating pipeline through a corresponding pipeline; the sixth material conveying pipe is communicated with the upper part of the dispersing and stirring tank through a ninth material conveying pipe; the eighth material conveying pipe is communicated with the upper part of the swelling and stirring tank through a tenth material conveying pipe.

2. The liquefaction plant as claimed in claim 1, wherein the mixer is provided with a biomass silo for supplying the biomass material to the mixer and a solvent tank for supplying the reaction solvent to the mixer.

3. The liquefaction plant according to claim 2, characterized in that said medium-temperature separator is in communication with the solvent tank through a respective conduit.

4. The liquefaction plant according to claim 1, wherein said first reactor and said second reactor are circulating suspended bed reactors.

5. A method for direct liquefaction of biomass into fuel oil using the liquefaction plant of claim 1, comprising the steps of:

crushing biomass, fully mixing the crushed biomass with hydrated ferric oxide in a mixer, sequentially passing through a dispersion stirring tank and a swelling stirring tank, entering a biomass slurry heating furnace for preheating, sequentially passing through a first reactor and a second reactor under the conditions that the reaction temperature is 250-550 ℃ and the pressure is 10-150 Pa to obtain a crude product, sequentially treating the crude product through a high-temperature separator, a reduced-pressure distiller, an online hydrogenation reactor, a medium-temperature separator and a normal-temperature separator to obtain a water-containing substance with the water content of 35 percent and semi-finished oil, and recovering pyroligneous liquor from the water-containing substance with the water content of 35 percent, wherein the heat value of the semi-finished oil is equal to 75-80 percent of the heat value of diesel oil.