CN107875977A - A kind of high-pressure spiral fast pyrogenation reaction unit - Google Patents

Abstract

The present invention relates to a kind of high-pressure spiral fast pyrogenation reaction unit, including body of heater, spiral reactor and burner, wherein spiral reactor is arranged in body of heater；Burner is uniformly distributed on the wall of body of heater, is heated for jetting out flames to spiral reactor.The device of the present invention disclosure satisfy that the working condition of HTHP, and can adjust the production composition of thermal decomposition product as requested, improve the thermal efficiency, reduce environmental pollution and production cost.

Description

A high-pressure spiral fast pyrolysis reaction device

technical field

The invention relates to a descending bed rapid pyrolysis reactor used in the coal chemical industry to prepare high value-added products such as high calorific value gas, high-quality semi-coke and high-quality oil, and more specifically relates to a high-pressure spiral rapid pyrolysis reactor Pyrolysis reaction device.

Background technique

my country's energy structure is characterized by rich coal, poor oil, and little gas. As the world's largest coal producer and consumer, coal resources will remain unshakable as my country's leading energy source for a long period of time. According to statistics, my country's proven coal reserves are 114.5 billion tons, of which, medium and low rank coal (lignite, low metamorphic bituminous coal) account for about 55.15% of the country's retained resources. Because low-rank coal has the characteristics of high moisture content, easy weathering, difficulty in sorting, and unsuitable for long-distance transportation and storage, its comprehensive utilization is greatly restricted. With the widespread use of modern comprehensive coal mining technology, coal pyrolysis technology is considered to be the most effective way to efficiently and cleanly utilize coal. However, in the field of pyrolysis, especially rapid pyrolysis has become a new and efficient pyrolysis method.

Rapid pyrolysis refers to the rapid heating of materials to the temperature required for pyrolysis under the condition of no oxygen or limited oxygen, so that the carbon-containing polymers rapidly undergo chemical bond breaking reactions, and the high temperature and high pressure working environment will increase the yield of pyrolysis products. Spawn rate has been greatly improved. At present, fast pyrolysis reactors are generally divided into reaction devices such as fluidized bed, moving bed, and rotating bed, and two methods are used to achieve the temperature distribution of the temperature field and the requirements of the heating rate. However, the use of heat carrier The fast reactor involves a series of complex processes such as the uniform distribution, mixing, and reaction of the carrier and the raw material, as well as the separation, re-preheating, and re-transportation of the downstream carrier and the semi-coke product, resulting in an increase in the failure rate and a decrease in the overall thermal efficiency. There are also carrier-free indirect heat transfer reactors, but the heat transfer efficiency is low, it is difficult to scale up, and more reactors with rectangular cross-sections are used. This structural reactor is only suitable for medium and low temperature, low pressure and normal pressure. Under the working conditions of high temperature and high pressure, the fast pyrolysis reactor without heat carrier still needs to be further developed.

Contents of the invention

Aiming at the deficiencies of the prior art, the present invention provides a new type of rapid pyrolysis reactor with external flame without heat carrier, which overcomes the shortcomings of existing equipment, structure and complex process, etc., can meet the working conditions of high temperature and high pressure, and can Adjust the production composition of pyrolysis products according to requirements, improve thermal efficiency, reduce environmental pollution and production costs.

Specifically, the present invention can achieve the following objectives:

1) Use primary energy to provide heat source, saving energy utilization from the energy structure;

2) Improve the pressure and heat resistance of the reactor to achieve the purpose of high pressure;

3) The reactor adopts a tubular structure, which improves stability, and simplifies the structure to reduce manufacturing costs;

4) Operation without heat carrier, simplify the system, reduce failure rate, improve system operation reliability, reduce energy consumption, and reduce mechanical wear;

5) The external flame greatly reduces the number of welds formed by the arrangement of radiant tubes, and improves the safety and reliability of the reactor under high temperature and high pressure operating conditions;

6) The scope of application is wider, the internal temperature of the reactor can reach 1000 ℃, and the internal pressure capacity can reach 3MPa.

In order to realize or reach above-mentioned object, the present invention adopts following technical scheme:

According to the present invention, a kind of high-pressure spiral rapid pyrolysis reaction device is provided, comprising furnace body, spiral reactor and burner, wherein spiral reactor is installed in furnace body; Burner is evenly arranged on the wall of furnace body, with The spiral reactor is heated by spraying flame.

According to one embodiment of the present invention, the spiral reactor includes a feed inlet, a reactor tube body, a pyrolysis gas outlet and a coke outlet, wherein the feed inlet is arranged on the upper part of the spiral reactor, and the reactor tube body is a spiral The main body of the spiral reactor, the pyrolysis gas outlet and the coke outlet are all arranged at the lower part of the spiral reactor.

According to one embodiment of the present invention, the wall thickness of the steel plate of the reactor pipe body is 6-15mm, the diameter of the reactor pipe body is 50-300mm, the middle diameter of the spiral reactor is 100-3000mm, and the section of the reactor pipe body The distance is not less than 180mm.

According to an embodiment of the present invention, the heat-resistant temperature of the reactor tube body is 500-1200° C., and the residence time of the materials in the reactor tube body is 6-9 s.

According to an embodiment of the present invention, the unfolded length of the spiral reactor is 12-405m, the height of the spiral reactor is 6-405m, and the spiral number of the spiral reactor is 1-390.

According to an embodiment of the present invention, the absolute pressure that the reactor tube bears is 1.0-10 MPa.

According to an embodiment of the present invention, the distance between every two adjacent spiral reactors is 100-9000 mm.

According to an embodiment of the present invention, the structure of the furnace body is rectangular, cylindrical or annular.

According to an embodiment of the present invention, the walls of the furnace body are built with high temperature resistant insulation materials to prevent heat loss.

According to an embodiment of the present invention, the wall thickness of the furnace body is not less than 300mm.

By adopting the above technical scheme, the present invention has the following advantages compared to the prior art:

1) The spiral reactor of the present invention adopts a heat-resistant steel pipe body and a spiral form, which has stronger high temperature and high pressure resistance.

2) The device of the present invention adopts an external flame, which greatly reduces the number of welds formed by the arrangement of radiant tubes, makes the integrity of the reactor tube body better, and improves the safety and reliability of the spiral reactor under high temperature and high pressure operating conditions Sex, which fundamentally reduces the risk of explosion.

3) The spiral reactor of the present invention is integrally installed in a furnace body full of flames and uniform in temperature, so that the distribution inside the spiral reactor is also more uniform, and this design avoids structural damage caused by large temperature differences.

4) Compared with the existing heat carrier fast pyrolysis reactor, the reactor of the present invention simplifies the structure, reduces the manufacturing cost, and improves the material utilization rate.

5) The reactor tube body of the spiral reactor of the present invention not only reduces the furnace height, increases the radiation surface of the tube body, but also increases the residence time of the material in the spiral reactor at the same height, thereby improving the thermal efficiency. Solution efficiency and reaction completeness.

6) The manufacture and installation of the whole device of the present invention are relatively simple, and the construction period is short.

7) The device of the present invention can realize diversified and large-scale industrial production according to the size of the production scale.

8) The device of the present invention can make the pyrolysis more thorough under the environment of high temperature and high pressure, the yield of pyrolysis gas is higher, and more importantly, it provides favorable conditions for the downstream production process.

9) Ribs can be installed on the inner wall of the reactor tube, which not only improves the strength of the tube body but also increases the radiation surface of the tube body in the unit space.

10) The present invention adopts the heating form of external heating and internal cloth, which greatly reduces the amount of welds on the reactor body, reduces the workload of installation and flaw detection, and more importantly, the safety of the reactor is higher under high temperature and high pressure environment. The use of the pipe body greatly simplifies the complexity of the structure, improves the utilization rate of materials, reduces the manufacturing cost, and can meet the requirements of the working environment with higher internal pressure and higher temperature.

11) The pyrolysis gas outlet of the present invention is arranged at the lower part of the spiral reactor and the upper part of the discharge area, and the pyrolysis gas is quickly exported from the outlet through the pressure difference between the inside and outside of the spiral reactor. The pyrolysis gas outlet is set at the bottom, and the particles pass through the entire spiral reactor from top to bottom, making it pyrolyzed more completely. Compared with the top and middle, the pyrolysis gas outlet is set, which reduces the number of carried particles in the gas and improves the Quality of pyrolysis gas.

Description of drawings

The above and/or additional aspects and advantages of the present invention will be more apparent and easily understood in the description of the embodiments in conjunction with the accompanying drawings, wherein:

Fig. 1 is the structural representation of the high-pressure spiral rapid pyrolysis reaction device along A-A direction of the embodiment of the present invention;

Fig. 2 is a sectional view of Fig. 1;

Fig. 3 is the structural representation of the spiral reactor of the embodiment of the present invention;

Fig. 4 is a cross-sectional view along B-B direction of Fig. 3 .

Explanation of reference signs

1 spiral reactor, 2 furnace body, 3 burner, 4 feed inlet, 5 reactor tube body, 6 pyrolysis gas outlet, 7 coke outlet.

Detailed ways

It should be understood that the embodiments of the invention shown in the exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in the present invention, those skilled in the art will readily appreciate that many modifications are possible without materially departing from the teachings of the subject matter of the invention. Accordingly, all such modifications are intended to be included within the scope of this invention. Other substitutions, modifications, changes and deletions can be made to the designs, operating conditions and parameters of the following exemplary embodiments without departing from the gist of the present invention.

As shown in Figures 1-4, the present invention provides a high-pressure spiral fast pyrolysis reaction device, the pyrolysis device adopts a spiral structure with an external flame, including a furnace body 2, a spiral reactor 1 and a burner 3, wherein The spiral reactor 1 is installed in the body of furnace 1 and includes a feed inlet 4, a reactor pipe body 5, a pyrolysis gas outlet 6 and a coke outlet 7; the burners 3 are evenly arranged on the wall of the body of furnace 2, with The spiral reactor 1 is heated by spraying flame.

In the present invention, the spiral reactor 1 is placed in the furnace body 2, the material flows inside the spiral reactor 1, and the burner 3 is installed on the furnace wall, wherein the burner 3 is located on the regenerative radiant tube, vertically The upper and lower layers of regenerative radiant tubes adopt a staggered distribution method, which makes the distribution of the reaction materials more uniform during the falling process, and is evenly arranged along the ring in the horizontal direction; the capacity and number of burners 3 can be adjusted according to the actual situation. The heat required by the furnace body 2 is arranged in a reasonable and orderly manner, and the flame ejected from the burner 3 is heated outside the spiral reactor 1, which greatly reduces the weld seam of the spiral reactor 1, and the safety under high pressure is higher.

In the embodiment of the present invention, the walls of the furnace body 2 are built with heat-resistant insulation materials to prevent heat loss, and the thickness of the walls of the furnace body 2 is greater than or equal to 300mm.

In the present invention, the material enters the reactor tube body 5 through the feed port 4, passes through the uniform distribution area in the upper part of the spiral reactor 1, and then passes through the high-temperature spiral reactor 1, and the material is in the process of falling. The high-temperature gas in the type reactor 1 is in contact with the tube wall of the spiral reactor 1 to form a high-efficiency heat exchange form in which three heat transfer modes of convection, heat conduction and radiation are simultaneously carried out, so that the material can be rapidly pyrolyzed within 6-9s The reaction produces pyrolysis gas and semi-coke, which fall into the discharge area at the lower end of the spiral reactor 1. Finally, the semi-coke produced by the reaction is discharged through the coke outlet 7, and the high-temperature and high-pressure pyrolysis gas is exported through the pyrolysis gas outlet 6.

In the embodiment of the present invention, the structure of the furnace body 2 can be in various forms such as rectangle, cylinder or ring.

In the present invention, the spiral reactor 1 is arranged inside the furnace body 2, and adopts a spiral tubular structure design. The spiral reactor 1 body has three material distribution areas, a reaction area and a discharge area formed from top to bottom. Partly, the feed port 4 of the spiral reactor 1 is the coke discharge port 7 at the upper part and the lower part, and the feed port 4 and the coke discharge port 7 are both arranged vertically. As shown in FIG. 3 , the feed port 4 of the spiral reactor 1 is in one-to-one correspondence with the feed port of the top reactor, and the coke outlet 7 of the spiral reactor 1 is in one-to-one correspondence with the coke outlet of the furnace body 2 . The tube wall of the spiral reactor 1 bears the effect of internal pressure. In order to meet the high-pressure process requirements, the thickness of the steel plate on the outer wall of the spiral reactor 1 can be increased. The material of the reactor tube 5 is heat-resistant cast steel to adapt to long-term Under high-temperature conditions, the thickness of the pipe wall can be 6-15mm according to the pressure and diameter. All solder joints are welded airtightly, and flaw detection is carried out. All incoming and outgoing materials are high-temperature and high-pressure resistant equipment; The ability to realize the control of the internal temperature of the spiral reactor 1 can make the temperature in the reactor tube body 5 reach: T=500-1200 ° C, which meets the temperature conditions required for rapid pyrolysis, and the temperature of the reactor tube body 5 The diameter is determined comprehensively according to factors such as production capacity, pressure bearing capacity, heating efficiency and material flow conditions, and can be set as: Φ=50-300mm. The height, helix angle, pitch diameter and total number of turns of the spiral reactor 1 must meet the requirements of the residence time of the material in the furnace body 2 and the requirements of the falling speed, wherein the helix angle must be greater than the angle of repose of the material (such as the The angle of repose is 27-45°), and the helix angle θ=30-90°.

In the present invention, in order to ensure the service life of the reactor tube body 5 and the heat transfer efficiency of the wall surface, the wall thickness of the steel plate of the reactor tube body 5 can be set as: δ=6-15mm; The middle diameter of the reactor 1 is: D=(2-10)Φ=100-3000mm; the pitch of the reactor tube body 5 of the spiral reactor is calculated by the helix angle θ (referring to when a helix rises one full turn The distance from the starting point to the end point): p=tanθ*πD=180mm-∞; the rapid heating rate of the material should be: C>100°C/s, so the material should be rapidly heated to 500-1200°C, which is in the reactor tube body 5 The movement time can be determined as: t=6-9s, the friction coefficient of pulverized coal to the pipe wall: μ=0.3-0.5, and the extended length of the reactor pipe body 5 can be calculated according to the residence time and friction coefficient of the material: L=1 /2(g*sinθ-μg*cosθ)*t ² , thus the expanded length of the spiral reactor 1: L=12-405m, the height of the spiral reactor 1: H=L*sinθ=6- 405m. The spiral number n of a single spiral reactor 1 is 1-390.

In the embodiment of the present invention, the absolute pressure that can be endured in the reactor tube body 5 is P: 1.0-10.0 MPa; the reactor tube body 5 adopts a spiral structure, which not only reduces the height of the furnace body 2, but also increases the radiation surface of the tube body , but also increases the residence time of the material in the spiral reactor 1, thereby not only improving the thermal efficiency but also more fully and thoroughly pyrolyzing the material; adding ribs to the inner wall of the reactor tube 5 not only improves the strength of the tube but also The radiation surface of the pipe body is added in the unit space. The spiral reactor 1 is arranged according to a certain rule in the furnace body 2, and its number can be determined according to the actual production capacity requirements. Each row can be set up to 2-10, and 2-10 rows can be arranged along the horizontal direction, or other, corresponding The distance between two adjacent spiral reactors 1: D1=(1-3)*D=100-9000mm.

In the embodiment of the present invention, the burner 3 is used to provide the main heat source required for the pyrolysis of the material in the spiral reactor 1, and is evenly distributed on the furnace body 2 along the height direction and the horizontal direction of the body, so that the reaction zone forms a Or multiple uniform temperature fields to meet the temperature required for the pyrolysis of materials in the spiral reactor 1. At the same time, the temperature of the furnace body 2 can be flexibly adjusted through the capabilities of each burner 3, so as to obtain reliable and stable temperature fields. , thus greatly improving the quality and output of products. The distance between burners 3 and the number of layers should be set according to the strength requirements of the furnace body and the height of the reactor. 2-10 layers can be arranged from bottom to top, and the number of each layer can be set according to the actual required heat.

In the embodiment of the present invention, the pyrolysis gas outlet 6 is set at the lower part of the spiral reactor 1 and the upper part of the discharge area, and the pyrolysis gas is quickly exported from the outlet through the pressure difference between the inside and outside of the spiral reactor 1 . The pyrolysis gas outlet 6 is set in the lower part, and the particles pass through the entire spiral reactor 1 from top to bottom, making its pyrolysis more complete. Compared with the top and middle, the pyrolysis gas outlet 6 is set to reduce the number of carried particles in the gas , improving the quality of pyrolysis gas.

In the embodiment of the present invention, the discharge area is located at the bottom of the spiral reactor 1, and the coke outlet 7 is arranged at the bottom of the discharge area, that is, the bottom of the spiral reactor 1, and the semi-coke passes through the gravity and the spiral reactor 1 The combined effect of the internal pressure is exported to the spiral reactor 1 through the coke outlet 7 .

In the present invention, the pyrolysis gas needs to be transported at high temperature and high pressure to meet the requirements of the downstream process. However, the existing fast pyrolysis reactor with a rectangular cross-section without heat carrier is only suitable for low-pressure transport and cannot meet the process requirements. Compared with the existing rectangular cross-section and circular cross-section heat-carrier-free rapid pyrolysis reactors, the present invention has wider application range, more reliable structure and higher safety. First of all, the structural form of the tube type is relatively stronger in pressure bearing capacity, more uniform in structural force, and better in stability. In addition, the present invention adopts the heating form of external heating and internal cloth, and the weld seam of the reactor body is greatly reduced, making the installation And the workload of flaw detection is reduced, and more importantly, the safety of the reactor under high temperature and high pressure environment is higher. The use of the pipe body greatly simplifies the complexity of the structure, improves the utilization rate of materials and reduces the manufacturing cost, and can meet the requirements of higher internal pressure and higher temperature working environment.

Example

As shown in Figures 1-4, the present invention designs a fast pyrolysis reactor in the form of a descending bed spiral. The pyrolysis device adopts a spiral structure with an external flame, and its main structure includes: spiral reactor 1, furnace body 2 and burner 3; wherein the spiral reactor 1 includes a feed inlet 4, a reactor tube body 5, a pyrolysis gas outlet 6 and a coke outlet 7, the spiral reactor 1 is installed in the furnace body 2, and the burner 3 Evenly arranged on the side wall of the furnace body, the burner 3 sprays flames to heat the spiral reactor 1 .

The furnace body 2 is circular, and the spiral reactor 1 is placed in the circular furnace body 2. The material flows inside the spiral reactor 1, and the flame is heated outside the spiral reactor 1, which greatly reduces the cost of the spiral reactor 1. Welding seam, under high pressure state, the safety is higher; the material enters the reactor tube body 5 through the feed port 4, and is uniformly distributed in the upper part of the spiral reactor 1, and then passes through the high-temperature spiral reactor 1, During the falling process, the material is in contact with the high-temperature gas in the spiral reactor 1 and the tube wall of the spiral reactor 1, forming a high-efficiency heat exchange form in which three heat transfer modes of convection, heat conduction and radiation are simultaneously carried out, so that the material is in the spiral reactor. The pyrolysis reaction is rapidly completed in the reactor 1, and pyrolysis gas and semi-coke are generated, which fall into the discharge area at the lower end of the spiral reactor 1, and finally the semi-coke produced by the reaction is discharged through the coke outlet 7, and the high-temperature and high-pressure heat The decomposed gas is exported through the pyrolysis gas outlet 6.

In this preferred embodiment, the walls of the furnace body 2 are built with high-temperature-resistant insulation materials to prevent heat loss. The thickness of the furnace wall is greater than or equal to 300mm, and the burner 3 is installed on the outer wall of the furnace body 2. In order to ensure that the reactor For the service life of the pipe body 5 and the heat transfer efficiency of the wall surface, the wall thickness of the steel plate of the reactor pipe body 5 can be set as: δ=10mm; in order to ensure smooth flow of materials, the middle diameter of the spiral reactor is: D=500mm, The helix angle θ is 45°; the pitch of the reactor tube body 5 is calculated by the helix angle θ: p=1.72m; the rapid heating rate of the material should be: C>100°C/s, so the material should be heated to 1000°C quickly, Its movement time in the tube of the spiral reactor 1 can be determined as t=6s, and the extended length of the reactor tube body 5 can be calculated according to the residence time of the material and the friction coefficient: L=30m, thus the spiral reactor 1 The extended length of the spiral reactor: L=80m, the number of spiral turns of the spiral reactor 1 is 5, the height of the spiral reactor: H=56m; the distance between adjacent spiral reactors 1 is 600mm.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the implementation scope of the present invention; if it does not depart from the spirit and scope of the present invention, any modification or equivalent replacement of the present invention shall be covered by the claims of the present invention. within the scope of protection.

Claims (10)

1. A kind of 1. high-pressure spiral fast pyrogenation reaction unit, it is characterised in that including body of heater, spiral reactor and burner, its Described in spiral reactor be arranged in the body of heater；The burner is uniformly distributed on the wall of the body of heater, is used for Jet out flames and heated to the spiral reactor.
2. 2. high-pressure spiral fast pyrogenation reaction unit according to claim 1, it is characterised in that the spiral reactor Including charging aperture, reactor body, pyrolysis gas outlet and coke outlet, wherein the charging aperture is arranged on the spiral reactor Top, the reactor body is the main body of the spiral reactor, and the pyrolysis gas outlet and the coke outlet are all provided with Put in the bottom of the spiral reactor.
3. 3. high-pressure spiral fast pyrogenation reaction unit according to claim 2, it is characterised in that the reactor body Steel plate wall thickness is 6-15mm, a diameter of 50-300mm of the reactor body, and the central diameter of the spiral reactor is 100- 3000mm, the pitch of the reactor body are not less than 180mm.
4. 4. high-pressure spiral fast pyrogenation reaction unit according to claim 3, it is characterised in that the reactor body Heat resisting temperature is 500-1200 DEG C, and residence time of the material in the reactor tube body is 6-9s.
5. 5. high-pressure spiral fast pyrogenation reaction unit according to claim 4, it is characterised in that the spiral reactor Length of run be 12-405m, the reactor body of the spiral reactor is highly 6-405m, the spiral reactor Spiral number be 1-390.
6. 6. high-pressure spiral fast pyrogenation reaction unit according to claim 5, it is characterised in that the reactor body is held The absolute pressure received is 1.0-10MPa.
7. 7. high-pressure spiral fast pyrogenation reaction unit according to claim 6, it is characterised in that per two neighboring spiral The spacing of reactor is 100-9000mm.
8. 8. high-pressure spiral fast pyrogenation reaction unit according to claim 1, it is characterised in that the structure of the body of heater is Rectangle, tubular or annular.
9. 9. high-pressure spiral fast pyrogenation reaction unit according to claim 1, it is characterised in that the wall of the body of heater is adopted Built by laying bricks or stones with resistant to elevated temperatures insulation material, for preventing scattering and disappearing for heat.
10. 10. high-pressure spiral fast pyrogenation reaction unit according to claim 9, it is characterised in that the wall of the body of heater Thickness is not less than 300mm.