CN106221817A - The device and method of high heating value gas is prepared based on double-fluidized-bed biomass pyrolytic - Google Patents

Abstract

The invention discloses a device and method for preparing high calorific value coal gas based on double fluidized bed biomass pyrolysis. The upper part of the reforming cyclone separator (1) passes through the reforming fluidized bed (2) and the bubbling fluidized bed ( 7) communicated, the bottom of the bubbling fluidized bed is connected with the bottom of the calcined fluidized bed (12) through the second U-shaped feeder (11), and the top of the calcined fluidized bed is connected with the calcined cyclone separator (15), The lower part of the calcining cyclone separator is connected to the storage tank (14), and the lower part of the storage tank is provided with a third U-shaped feeder (13) and communicated with the lower part of the reforming fluidized bed at the same time; the lower part of the reforming cyclone separator passes through The first U-shaped feeder (4) communicates with the bubbling fluidized bed; the bottom of the hopper (3) is connected to the screw feeder (5), and the output end of the screw feeder is connected to the inner chamber of the bubbling fluidized bed; The device prepares synthesis gas, which can reduce tar production and pipeline blockage by tar, prolong the service life of equipment, and improve the calorific value and gasification efficiency of synthesis gas.

Description

Device and method for preparing high calorific value gas based on double fluidized bed biomass pyrolysis

technical field

The invention relates to a device for preparing high calorific value gas and a preparation method thereof, in particular to a device for preparing high calorific value gas based on double fluidized bed biomass pyrolysis and a preparation method thereof.

Background technique

At present, human beings are facing the dual pressure of economic growth and environmental protection. Changing the way of energy production and consumption, using modern technology to develop and utilize renewable energy including biomass energy, is conducive to the establishment of a sustainable energy system and the promotion of social and economic development. It is of great significance to improve the ecological environment and get rid of the dependence on fossil energy.

Biomass energy has always been one of the important energy sources for human survival, including energy trees, energy crops, aquatic plants, various organic wastes, etc., which are converted into renewable energy resources through photosynthesis and are organic storage of solar energy. , Biomass energy is the most common renewable energy on the earth, with a huge amount, and it is the fourth energy after coal, oil, and natural gas. It is estimated that the heat equivalent of the earth's annual water and terrestrial biomass production is about 3×10 ²¹ J, which is 10 times the current total energy consumption in the world. my country is quite rich in biomass resources. Only the resources of various agricultural wastes (such as straw, etc.) are 308 million tons of standard coal per year, and the amount of fuelwood resources is 130 million tons of standard coal. The amount can reach 650 million tons of standard coal.

At present, there are many ways to utilize biomass energy, including biomass combustion technology, biomass gasification technology, biomass pyrolysis technology, biomass direct liquefaction technology, biofuel ethanol technology, biodiesel preparation technology, and biohydrogen production technology. , biogas technology, etc., among which biomass gasification is an important way of biomass energy conversion. Biomass has the characteristics of high volatile component content, high carbon activity, low sulfur, nitrogen and ash content, and is an ideal gasification raw material.

Biomass gasification means that after the biomass raw material is processed, it reacts with the gasification agent in the gasification furnace for gasification and cracking to obtain combustible gas, and further purifies the output gas as required to obtain the required product gas. The principle is that under the action of the gasification medium, the biomass undergoes pyrolysis, oxidation, reduction, and reformation reactions. The pyrolysis process is accompanied by the generation of tar. The tar can be further pyrolyzed or catalytically cracked into small molecular hydrocarbons. Thereby obtaining combustible gases such as hydrogen, carbon monoxide, and methane.

At present, the biomass gasifiers used in China are generally fixed bed gasifiers or fluidized bed gasifiers. However, fixed-bed gasifiers are rarely used because of their shortcomings such as small production capacity, large tar output, and low gasification efficiency. Fluidized-bed gasifiers have become the preferred furnace type for biomass gasification because of their High gasification efficiency, wide adaptability of raw materials, large-scale industrial application and relatively low tar content in syngas.

The main problems of the biomass gasification device put into operation are complex structure, high operating cost, low gasification efficiency and poor adaptability of biomass, but the biggest problem is the large tar output and serious secondary pollution. In order to crack tar, the conventional method is to adopt a two-step method, that is, the biomass is first gasified in a fluidized bed gasifier to generate pyrolysis gas, and then the product gas is converted into synthesis gas through catalytic reforming and tar cracking, and pyrolysis And reforming is carried out in two reactors connected in series.

Contents of the invention

Technical problem: The technical problem to be solved by the present invention is to provide a device and method for preparing high calorific value gas based on double fluidized bed biomass pyrolysis, using the device to prepare high calorific value gas while reducing the output of tar and reducing the amount of gas in the bed. Pipeline blockage, prolong the service life of equipment, while the carbon monoxide and hydrogen produced by thermal cracking and catalytic cracking of tar can increase the calorific value of the product gas, thus also improving the gasification efficiency of biomass.

Technical solution: In order to solve the above-mentioned technical problems, the technical solution adopted by the device for preparing high calorific value gas based on double-fluidized-bed biomass pyrolysis is as follows:

The upper part of the reforming cyclone separator communicates with the bubbling fluidized bed through the reforming fluidized bed, and the lower part of the bubbling fluidized bed communicates with the lower part of the calcined fluidized bed through the second U-shaped feeder, and the calcined fluidized bed The upper part of the calcining cyclone separator is connected to the calcining cyclone separator, and the lower part of the calcining cyclone separator is connected to the storage tank. The lower part of the storage tank is provided with a third U-shaped feeder and communicates with the lower part of the reforming fluidized bed at the same time; the reforming cyclone separator The lower part communicates with the bubbling fluidized bed through the first U-shaped feeder; the lower part of the hopper is connected to the screw feeder, and the output end of the screw feeder is connected to the inner cavity of the bubbling fluidized bed;

The top of the reforming cyclone separator is provided with a synthesis gas outlet connected to the tar cracker, and the top of the calcination cyclone separator is provided with a flue gas outlet connected to the air preheater. Tar cracker; the bottom of the bubbling fluidized bed is provided with a water vapor inlet and a slag discharge pipe, the bottom of the second U-shaped feeder is provided with a second slag discharge pipe, and the bottom of the calcined fluidized bed is provided with an air Inlet and third slag discharge pipe.

The bottom of the bubbling fluidized bed is provided with a hood-type air distribution plate.

The method for preparing high calorific value coal gas by pyrolysis of the present invention comprises the following processes:

The biomass raw material is put into the hopper, and the biomass raw material is sent into the bubbling fluidized bed pre-installed with limestone by the screw feeder. When the fluidized bed is heated to 750-850°C, the biomass raw material is pyrolyzed and gasified in the bubbling fluidized bed to generate pyrolysis gas and solid residue. The pyrolysis gas contains carbon monoxide, hydrogen, carbon dioxide, methane and tar. The solid residue contains coke, and the pyrolysis gas rises into the reforming fluidized bed, and the reforming fluidized bed is heated to keep the temperature of the reforming fluidized bed at 900°C. The solid residue is deposited at the bottom of the bubbling fluidized bed, and the solid The residue and limestone enter the calcined fluidized bed through the second U-shaped feeder, heat the calcined fluidized bed to keep the temperature in the calcined fluidized bed at 950°C, and feed air into the air inlet of the calcined fluidized bed, and the solid The coke in the residue burns with oxygen to release a large amount of heat, which decomposes the calcium carbonate in the limestone into solid particle calcium oxide and gaseous carbon dioxide. At the top of the calcined fluidized bed, the calcium carbonate is completely decomposed into calcium oxide and carbon dioxide to form gas-solid Two-phase product, the gas-solid two-phase product is separated by the calcination cyclone separator, the flue gas enters the air preheater to preheat the air entering the tar cracker, and the calcium oxide passes through the storage tank and returns through the third U-shaped return device To the lower part of the reforming fluidized bed, in the reforming fluidized bed, the pyrolysis gas carries calcium oxide up, and the calcium oxide absorbs carbon dioxide in the pyrolysis gas to form calcium carbonate, which promotes the water-gas shift reaction and methane reforming reaction, and at the same time Calcium oxide, nickel oxide, etc. are used as catalysts for tar cracking. Catalytic cracking of tar generates hydrogen and carbon monoxide gas. High temperature of reforming fluidized bed promotes thermal cracking of tar. Catalytic cracking and thermal cracking reduce tar production, thereby reducing pipeline blockage. Extend the maintenance cycle of equipment and improve production efficiency; the reformed gas is obtained after the pyrolysis gas is reformed in the reforming fluidized bed, and the carbonic acid separated by the reforming cyclone separator is obtained after the reformed gas is separated from the gas by the reforming cyclone separator Calcium is sent back to the bubbling fluidized bed through the first U-shaped feeder to realize the recycling of the heat carrier, and the gas discharged from the synthesis gas outlet of the reforming cyclone separator is synthesis gas, which enters the tar cracker to make the residual tar Further cracking, finally get gas.

The reforming fluidized bed is preheated by the bubbling fluidized bed, and the temperature reaches about 900 degrees Celsius, which causes the internal tar to undergo high-temperature thermal cracking. At the same time, due to the presence of compounds such as calcium oxide and nickel oxide, the catalytic tar undergoes catalytic cracking reactions. Two kinds of cracking The reaction reduces the production of tar in the bed, thereby reducing the clogging of pipes by tar, and the cracking of tar can generate additional heat.

The high-temperature flue gas separated by the calcination cyclone separator can be used to preheat the air in the air preheater, and the synthesis gas separated by the reforming cyclone separator is rich in a large amount of high calorific value hydrogen, carbon monoxide and other gases, and the tar cracker can further remove tar , produce high calorific value gas, and can be used for gas turbine, diesel engine power generation, heating and heating, so as to realize the cogeneration of heat and electricity.

Beneficial effect: compared with the prior art, the present invention has the following advantages:

(1) Reduce the output of tar, increase the calorific value of synthesis gas, and improve the efficiency of biomass gasification. In the device of the present invention, in the reforming fluidized bed, the tar is catalyzed and cracked by the heat carrier particles calcium oxide and nickel oxide, and combustible gases such as hydrogen and carbon monoxide are decomposed, and hydrogen and carbon monoxide are decomposed by high-temperature thermal cracking at the same time, which promotes the reduction of tar production. , so as to reduce pipeline blockage, prolong equipment maintenance cycle, improve production efficiency, and the increase of combustible gases such as hydrogen will increase the calorific value of gas and improve the overall gasification efficiency.

(2) The cyclic regeneration of the heat carrier catalyst is realized. Taking limestone heat carrier as an example, in the calcination fluidized bed, the heat of coke combustion causes the main component of limestone, calcium carbonate, to decompose into CaO and CO ₂ at high temperature, and CaO carries heat into the reforming fluidized bed reactor, which is The entire reaction provides heat. During this process, CaO absorbs CO ₂ in the pyrolysis gas, promotes the water gas shift reaction CO+H ₂ O=H ₂ +CO ₂ and methane reforming reaction, and at the same time, CaO acts as a catalyst to rapidly catalytically crack the tar produced by pyrolysis , to generate small molecular gases such as _H2 and CO, so that the tar content in the pyrolysis gas is reduced, and the output of synthesis gas is greatly increased. CaO regenerates CaCO ₃ after absorbing CO ₂ , and returns it to the fluidized bed gasifier, realizing the recycling of the heat carrier catalyst.

(3) The graded conversion of biomass energy has been realized. In the present invention, the biomass raw material is firstly gasified in a pyrolysis fluidized bed to obtain pyrolysis gas, tar and coke. The coke enters the calcination fluidized bed for combustion, and its heat is converted to the heat carrier, which returns this part of the heat to the reforming fluidized bed to provide the required heat for tar cracking and pyrolysis gas reforming. In addition, the coke is burned in the calcined fluidized bed, which improves the dust removal rate and can significantly reduce impurities such as dust and carbon particles in the synthesis gas. The pyrolysis gas generated by gasification is subsequently reformed, which reduces the requirements for the gasification process.

(4) Compared with the conventional method for producing synthesis gas from biomass, the present invention facilitates the integration of heat. In the present invention, the heat generated by the combustion of coke in the calcined fluidized bed will be provided to the pyrolysis gas through the heat carrier, providing conditions for the reformation of the pyrolysis gas and the cracking reaction of tar. This makes full use of the originally difficult to handle coke.

(5) Cogeneration of heat and electricity has been realized. While utilizing biomass energy, the device outputs high-calorific-value syngas and high-temperature flue gas, among which high-calorific-value syngas can be used for gas turbine or diesel engine power generation, heating, etc., and produces high-calorific product gas and high-temperature flue gas It can heat water vapor for steam turbine power generation, preheat air required for fluidized bed, energy saving and emission reduction.

(6) Realized the application of distributed energy system. The device is suitable for many scenarios and complements the centralized energy system to help solve the problem of energy supply in scattered and remote areas. The source of bed materials is extensive and most of them are wastes with no practical use value, which reduces environmental pollution and energy shortage. question.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

In the figure there are: reforming cyclone separator 1, reforming fluidized bed 2, hopper 3, first U-shaped feeder 4, screw feeder 5, hood type air distribution plate 6, bubbling fluidized bed 7, The first slag discharge pipe 8, the second slag discharge pipe 9, the third slag discharge pipe 10, the second U-shaped feeder 11, the calcined fluidized bed 12, the third U-shaped feeder 13, the storage tank 14, Calcination cyclone separator 15, air preheater 16 and tar cracker 17.

detailed description

The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings.

Implementation plan one:

As shown in Figure 1, a device for preparing high calorific value gas based on double fluidized bed biomass pyrolysis of the present invention includes a reforming cyclone separator 1, a reforming fluidized bed 2, a hopper 3, a first U-shaped return Feeder 4, screw feeder 5, hood type air distribution plate 6, bubbling fluidized bed 7, first slag discharge pipe 8, second slag discharge pipe 9, third slag discharge pipe 10, second U-shaped return Feeder 11, calcined fluidized bed 12, third U-shaped feeder 13, storage tank 14, calcined cyclone separator 15, air preheater 16 and tar cracker 17. The bottom of the bubbling fluidized bed 7 is provided with a water vapor inlet. The bottom of the calcining fluidized bed 12 is provided with an air inlet. The top of the reforming cyclone separator 1 is provided with a synthesis gas outlet. The top of the calcining cyclone separator 15 is provided with a flue gas outlet. The lower part of the first U-shaped feeder 4 is provided with a first feeder air inlet. Air is introduced into the first return air inlet as the return air to promote the process of return. The lower part of the second U-shaped feeder 11 is provided with a second feeder air inlet. Air is introduced into the second return air inlet as the return air to promote the process of return. The lower part of the third U-shaped feeder 13 is provided with a third feeder air inlet. Air is introduced into the third return air inlet as the return air to promote the process of return. The discharge port of the hopper 3 is connected to the feed end of the screw feeder 5, and the discharge end of the screw feeder 5 is located in the inner cavity of the bubbling fluidized bed 7, and the lower part of the bubbling fluidized bed 7 passes through the second U Type return feeder 11 communicates with the lower part of the calcined fluidized bed 12, the upper part of the calcined fluidized bed 12 communicates with the upper part of the calcined cyclone separator 15, and the lower part of the calcined cyclone separator 15 passes through the third U-shaped return feeder 13 It communicates with the lower part of the reforming fluidized bed 2, and the upper part of the reforming fluidized bed 2 communicates with the upper part of the reforming cyclone separator 1, and the lower part of the reforming cyclone separator 1 passes through the first U-shaped feeder 4 and The lower part of the bubbling fluidized bed 7 is connected.

Further, the device for preparing high calorific value gas based on biomass pyrolysis in double fluidized beds also includes a hood-type air distribution plate 6 fixed on the bottom surface inside the bubbling fluidized bed 7 . The hood-type air distribution plate 6 is set to distribute the air evenly, so that the biomass raw material in the bubbling fluidized bed 7 is evenly mixed with water vapor, and a good fluidization state is established. At the same time, the directional blowing effect of the hood is beneficial to coke and The limestone enters the calcining fluidized bed 12 through the second U-shaped feeder 11 .

The method for preparing synthesis gas based on the above-mentioned device for preparing high calorific value coal gas by pyrolysis of double fluidized bed biomass includes the following process:

Put the biomass raw material into the hopper 3, send the biomass raw material into the bubbling fluidized bed 7 pre-installed with limestone from the screw feeder 5, and at the same time, feed water into the water vapor inlet at the bottom of the bubbling fluidized bed 7 Steam, when the bubbling fluidized bed 7 is heated to 750-850°C, the biomass raw material is pyrolyzed and gasified in the bubbling fluidized bed 7 to generate pyrolysis gas and solid residue, and the pyrolysis gas contains carbon monoxide and hydrogen , carbon dioxide, methane and tar and other products, the solid residue contains coke, the pyrolysis gas rises to the reforming fluidized bed 2, and the reforming fluidized bed 2 is heated to keep the temperature of the reforming fluidized bed 2 at 900 °C, and the solid The residue is deposited at the bottom of the bubbling fluidized bed 7, and the solid residue and limestone enter the calcined fluidized bed 12 through the second U-shaped feeder 11, and the calcined fluidized bed 12 is heated to maintain the temperature in the calcined fluidized bed 12. At 950°C, air is introduced into the air inlet of the calcining fluidized bed 12, and the coke in the solid residue is combusted with oxygen to release a large amount of heat, so that the calcium carbonate in the limestone is decomposed into solid particle calcium oxide and gaseous carbon dioxide. At the top of the chemical bed 12, calcium carbonate is completely decomposed into calcium oxide and carbon dioxide to form a gas-solid two-phase product. After the gas-solid two-phase product is separated by the calcining cyclone separator 15, the calcium oxide is returned through the third U-shaped feeder 13. To the lower part of the reforming fluidized bed 2, in the reforming fluidized bed 2, the pyrolysis gas carries calcium oxide up, and the calcium oxide absorbs carbon dioxide in the pyrolysis gas to form calcium carbonate, which promotes the water gas shift reaction and methane reforming reaction At the same time, calcium oxide, nickel oxide, etc. are used as catalysts for tar cracking. Catalytic cracking of tar generates hydrogen and carbon monoxide gas. The high temperature of reforming fluidized bed 2 promotes thermal cracking of tar. Blockage, prolong equipment maintenance cycle, improve production efficiency, pyrolysis gas reformed in reforming fluidized bed 2 to obtain reformed gas, reformed gas through reforming cyclone separator 1 gas-solid separation, reforming cyclone separation The calcium carbonate separated from the device 1 is sent back to the bubbling fluidized bed 7 through the first U-shaped return device 4 to realize the recycling of the heat carrier, and the gas discharged from the synthesis gas outlet of the reforming cyclone separator 1 is synthesis gas.

In the above-mentioned device, the dried biomass is sent into the bubbling fluidized bed 7 by the screw feeder 5, reacts with water vapor, is pyrolyzed and gasified, and the generated pyrolysis gas rises into the reforming reaction bed, increasing the weight Adjust the temperature of the reactor to promote the pyrolysis reaction of tar and reduce the output of tar. The hydrogen and carbon dioxide produced at the same time can increase the calorific value of the synthesis gas; the solid residue after pyrolysis is mainly coke, and coke and heat carrier calcium carbonate enter through the feeder In the calcining fluidized bed 12; the calcining fluidized bed 12 is fed with oxygen, so that the coke burns in the oxygen to release heat, and provides heat for the decomposition of calcium carbonate. separation, the flue gas is discharged, and the calcium oxide particles return to the lower part of the reforming reaction bed, and rise under the entrainment of the pyrolysis gas flow. The calorific value of the whole gas, the reformed gas is separated from gas and solid to obtain synthesis gas, and the regenerated calcium carbonate particles are returned to the bubbling fluidized bed 7 for recycling; the sensible heat of the produced synthesis gas can be used to provide heat for biomass drying .

In the above method, limestone is selected as heat-carrying particles, decomposed and heated in the calcined fluidized bed 12, providing heat for the reaction in the reforming fluidized bed 7, and promoting the water-gas shift reaction, methane reforming reaction and tar cracking reaction, and then Regeneration, to achieve recycling. The heat-carrying particles can also choose _Ni /Al ₂ O ₃ or Ca/Al ₂ O ₃ .

Implementation plan two:

As shown in Figure 1, a device for preparing high calorific value gas based on double fluidized bed biomass pyrolysis of the present invention includes a reforming cyclone separator 1, a reforming fluidized bed 2, a hopper 3, a first U-shaped return Feeder 4, screw feeder 5, hood type air distribution plate 6, bubbling fluidized bed 7, first slag discharge pipe 8, second slag discharge pipe 9, third slag discharge pipe 10, second U-shaped return Feeder 11, calcined fluidized bed 12, third U-shaped feeder 13, storage tank 14, calcined cyclone separator 15, air preheater 16 and tar cracker 17.

It can be known from Embodiment 1 that after the high-temperature flue gas and high-calorific-value syngas are separated from the calcination cyclone separator 15 and the reforming cyclone separator 1 . The high-temperature flue gas can be sent into the boiler to heat the working medium (water or steam) in the heating surface, and share the energy source of the boiler part, so as to achieve the purpose of energy saving and emission reduction. The heated working medium can be sent into The steam turbine generates electricity, and the high-temperature flue gas can continue to enter the air preheater 16 to preheat the air that is about to enter the calcining fluidized bed 12 to provide additional heat for the combustion of the calcining fluidized bed 12. At the same time, the high-temperature flue gas is undergoing multiple After the heat exchange, the temperature also drops, and after being discharged through the dust collector, the harm and pollution caused are also greatly reduced. The high-calorific-value syngas can be sold or used as high-calorific-value product gas after passing through the dust collector, and can also be sent to a gas turbine for power generation, and the high-temperature gas generated can be used for heating. To sum up, the cogeneration of heat and electricity in the same device can be realized, and the efficient utilization of biomass energy can be realized, which not only solves the problem of waste gas biomass treatment, but also helps alleviate the problem of energy shortage and realize resource Recycling.

Implementation plan three:

As shown in Figure 1, a device for preparing high calorific value gas based on double fluidized bed biomass pyrolysis of the present invention includes a reforming cyclone separator 1, a reforming fluidized bed 2, a hopper 3, a first U-shaped return Feeder 4, screw feeder 5, hood type air distribution plate 6, bubbling fluidized bed 7, first slag discharge pipe 8, second slag discharge pipe 9, third slag discharge pipe 10, second U-shaped return Feeder 11, calcined fluidized bed 12, third U-shaped feeder 13, storage tank 14, calcined cyclone separator 15, air preheater 16 and tar cracker 17.

The device has a simple structure and is easy to build, and its scale can be changed according to actual needs. It is suitable for a variety of scenes and sites. The source of bed materials is wide, which can be lignocellulosic materials such as straws and trees other than grain and fruits in the agricultural and forestry production process. , leftovers from the agricultural product processing industry, agricultural and forestry waste, and livestock manure and waste in the production process of animal husbandry are reliable distributed energy systems that can complement centralized energy systems and help solve the problem of distributed and remote areas. Energy supply problems.

Claims (5)

1. the device preparing high heating value gas based on double-fluidized-bed biomass pyrolytic, it is characterised in that reformation cyclonic separation The top of device (1) is connected with bubbling fluidized bed (7) by reformation fluid bed (2), and the 2nd U is passed through in the bottom of bubbling fluidized bed (7) Type material returning device (11) and the bottom Lian Liantong of calcining fluid bed (12), calcine the top connection calcining cyclonic separation of fluid bed (12) Device (15), the bottom of calcining cyclone separator (15) connects storage tank (14), and the bottom of storage tank (14) is provided with the 3rd U-shaped returning charge Device (13) connects with the bottom of reformation fluid bed (2) simultaneously；The first U-shaped material returning device is passed through in the bottom of reformation cyclone separator (1) (4) connect with bubbling fluidized bed (7)；The bottom of hopper (3) connects screw feeder (5), the output termination drum of screw feeder (5) The inner chamber of bubble fluid bed (7)；

The top of reformation cyclone separator (1) is provided with syngas outlet and connects tar cracker (17), calcining cyclone separator (15) Top be provided with exhanst gas outlet and connect air preheater (16), the import input air of economizer bank in air preheater (16), Outlet connects tar cracker (17)；The bottom of described bubbling fluidized bed (7) is provided with steam entry and scum pipe (8), the 2nd U The bottom of type material returning device (11) is provided with the second scum pipe (9), and the bottom of calcining fluid bed (12) is provided with air intake and the 3rd row Slag pipe (10).

The device preparing high heating value gas based on double-fluidized-bed biomass pyrolytic the most according to claim 1, its feature exists In, the described bottom in bubbling fluidized bed (7) is provided with wind-cowl air distribution plate (6).

3. the method that high heating value gas is prepared in a device pyrolysis as claimed in claim 1, it is characterised in that described method Including procedure below:

Putting into biomass material in hopper (3), biomass material is sent into the bubbling being preinstalled with limestone by screw feeder (5) In fluid bed (7), meanwhile, the steam entry to bubbling fluidized bed (7) bottom is passed through steam, when bubbling fluidized bed (7) quilt When being heated to 750 850 DEG C, biomass material is pyrolytic gasification in bubbling fluidized bed (7), generates pyrolysis gas and solid residue, Comprising carbon monoxide, hydrogen, carbon dioxide, methane and tar in pyrolysis gas, solid residue comprises coke, and pyrolysis gas rises to weight In whole fluid bed (2), heated reformate fluid bed (2), make the temperature of reformation fluid bed (2) be maintained at 900 DEG C, solid residue deposits Calcining fluid bed (12) is entered through the second U-shaped material returning device (11) at the bottom of bubbling fluidized bed (7), solid residue and limestone In, heating and calcining fluid bed (12), make the temperature in calcining fluid bed (12) be maintained at 950 DEG C, to calcining fluid bed (12) Air intake is passed through air, the coke in solid residue and oxygen combustion, releases substantial amounts of heat, makes the calcium carbonate in limestone Being decomposed into solid particulate oxidation calcium and atmospheric carbon dioxide, at the top of calcining fluid bed (12), calcium carbonate is completely decomposed into oxygen Change calcium and carbon dioxide, form gas-particle two-phase product, this gas-particle two-phase product after calcining cyclone separator (15) separates, flue gas Entering air preheater (16) preheating and enter the air of tar cracker, calcium oxide passes through storage tank (14), through the 3rd U-shaped returning charge Device (13) returns to the bottom of reformation fluid bed (2), and in reformation fluid bed (2), pyrolysis gas carries calcium oxide and rises, calcium oxide Absorb the carbon dioxide in pyrolysis gas, form calcium carbonate, promote water gas shift reaction and methane reforming reaction, meanwhile, oxidation Calcium, nickel oxide etc. generate hydrogen and CO (carbon monoxide converter) gas, reformation fluid bed as the catalyst of coke tar cracking, catalytic cracking of tar (2) high temperature promotes tar to produce thermal cracking, and catalytic pyrolysis and thermal cracking promote tar yield to reduce, thus reduce line clogging feelings Condition, extension device maintenance period, improves production efficiency；Pyrolysis gas obtains reformation gas after reforming in reformation fluid bed (2), reforms Gas is after reformation cyclone separator (1) gas solid separation, and reformation cyclone separator (14) isolated calcium carbonate is through the first U-shaped returning charge Device (4) sends back in bubbling fluidized bed (7), it is achieved heat transfer medium circuit utilizes, from the syngas outlet of reformation cyclone separator (1) Discharge gas is synthesis gas, enters tar cracker (17) and makes residu tar crack further by high temperature, finally gives coal gas.

The method of high heating value gas is prepared in pyrolysis the most according to claim 3, it is characterised in that reformation fluid bed (2) is subject to To the preheating of bubbling fluidized bed (7), temperature reaches 900 degrees centigrade, makes internal tar produce high temperature pyrolysis, simultaneously because There is the compound such as calcium oxide, nickel oxide, catalytic tar generation catalytic cracking reaction, in two kinds of cracking reactions promote bed, tar produces Amount reduces, thus reduces pipeline by tar stopping state, and can produce additional heat after coke tar cracking.

The method of high heating value gas is prepared in pyrolysis the most according to claim 3, it is characterised in that calcining cyclone separator (15) isolated high-temperature flue gas can be used for air preheater (16) preheated air, reformation cyclone separator (1) isolated conjunction Becoming gas rich in gases such as the hydrogen of a large amount of high heating values, carbon monoxides, tar cracker (17) can further remove tar removing, raw Output high heating value gas, and can be used for gas turbine, diesel power generation, heating, thus realize thermoelectricity gas alliance.