A device for heating and processing of fine coal gasification slag stream

Abstract

The application discloses a kind of heating and processing device for fine slag fluid of pulverized coal gasification, belong to the field of fine slag fluid resource utilization of pulverized coal gasification, including main combustion chamber, secondary combustion chamber and shaft flue;Between main combustion chamber and secondary combustion chamber, and between secondary combustion chamber and shaft flue are provided with cyclone separator, the back material part of the cyclone separator is communicated with main combustion chamber, and energy recovery part is further provided in the shaft flue, and the energy recovery part is communicated with main combustion chamber, and the fuel of the main combustion chamber is the fine slag generated after pulverized coal gasification;The fine slag after pulverized coal gasification is burned by the main combustion chamber, and the energy in tail gas is recovered and filled into main combustion chamber for secondary use by energy recovery part;Secondary combustion chamber is simultaneously used to burn material again, to realize the resource utilization of fine slag after pulverized coal gasification, solid particles and gas are separated by cyclone separator, and solid particles are burned again in main combustion chamber, so that fine slag after pulverized coal gasification is burned more fully.

Description

Technical Field

[0001] This invention belongs to the field of resource utilization technology of fine slag fluid from pulverized coal gasification, and specifically relates to a heating and treatment device for fine slag fluid from pulverized coal gasification. Background Technology

[0002] Currently, the resource utilization pathways for pulverized coal gasification slag mainly fall into two categories, but both have significant limitations. One category involves applying it to building material production, soil and water remediation, or the preparation of high-value-added materials. However, in the building materials sector, the high residual carbon content (typically around 20%, and sometimes exceeding 40%) and correspondingly high loss on ignition of the gasification slag not only fail to meet the requirements for cement admixtures, but the residual carbon also hinders the cementitious reaction, affecting the performance of building materials and making direct resource utilization difficult. Although there are laboratory studies on high-value utilization technologies such as the preparation of novel foamed concrete and non-fired ceramsite, these technologies are often limited by processing scale or economic efficiency, making large-scale industrial application difficult. The other mainstream technology involves co-firing the slag using circulating fluidized bed boilers or conventional pulverized coal boilers to recover the residual calorific value from the slag. However, this approach faces serious challenges: First, the high moisture content of gasified fine slag, when directly co-fired, reduces boiler efficiency and corrodes boiler pipelines; simultaneously, increased ash content in the flue gas exacerbates equipment wear. Second, due to the high ash content of the fine slag, its calorific value is far lower than that of conventional fuel coal, severely limiting the co-firing ratio and processing scale. Third, the residual carbon particles in the gasified fine slag, after undergoing high-temperature gasification, may have their pore structure blocked by molten inorganic matter, resulting in lower reactivity than raw coal, leading to incomplete combustion and poor incineration. Furthermore, attempts have been made to return the fine slag to the coal slurry preparation system for recycling, but this easily leads to increased equipment wear and decreased gasification system efficiency. Therefore, currently, a large amount of pulverized coal gasification fine slag is still disposed of through landfill, which not only occupies land but also poses environmental risks such as surface dust, water and heavy metal pollution due to its high moisture content, resulting in resource waste.

[0003] In summary, existing technologies have failed to effectively address the challenges of large-scale, efficient, and economical resource utilization posed by the high moisture content and low calorific value of pulverized coal gasification slag. Therefore, there is an urgent need to develop a new technology capable of large-scale, efficient, and low-cost resource utilization of pulverized coal gasification slag, particularly a technological approach that can effectively reduce its moisture content and improve its energy recovery efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a heating and treatment device for fine slag fluid from pulverized coal gasification, addressing the aforementioned shortcomings and solving the problem of the difficulty in efficiently utilizing the high moisture content of fine coal gasification slag in the prior art.

[0005] This invention is achieved through the following scheme: A heating and treatment device for fine slag fluid from pulverized coal gasification includes a main combustion chamber, a secondary combustion chamber, and a vertical flue. Cyclone separators are installed between the main combustion chamber and the secondary combustion chamber, and between the secondary combustion chamber and the vertical flue. The return section of the cyclone separator is connected to the main combustion chamber. An energy recovery section is also installed in the vertical flue, and the energy recovery section is connected to the main combustion chamber. The fuel in the main combustion chamber is the fine slag produced after pulverized coal gasification.

[0006] Based on the structure of the heating and treatment device for fine slag fluid from pulverized coal gasification described above, the cyclone separator between the main combustion chamber and the secondary combustion chamber is a first-stage cyclone separator, and the cyclone separator between the secondary combustion chamber and the vertical flue is a second-stage cyclone separator; the feed port for the fine slag produced after pulverized coal gasification is located on the inlet flue of the first-stage cyclone separator, and a buffer silo is provided above the feed port.

[0007] Based on the structure of the heating and treatment device for fine slag fluid from pulverized coal gasification described above, a primary return feeder is provided at the bottom of the primary cyclone separator, and a secondary return feeder is provided at the bottom of the secondary cyclone separator; both the primary and secondary return feeders are connected to the bottom of the main combustion chamber.

[0008] Based on the structure of the heating and treatment device for fine slag fluid from pulverized coal gasification described above, the inlet of the secondary combustion chamber is connected to the outlet of the primary cyclone separator, and the outlet of the secondary combustion chamber is connected to the inlet of the secondary cyclone separator.

[0009] Based on the structure of the heating and treatment device for fine slag fluid in pulverized coal gasification described above, the secondary combustion chamber is an overall U-shaped structure, which is surrounded by a membrane wall, and the medium inside the pipe is a mixture of steam and water.

[0010] Based on the structure of the heating and treatment device for fine slag fluid in pulverized coal gasification described above, the main combustion chamber has a rectangular cross-section, and the inner surfaces of all four walls of the main combustion chamber are covered with wear-resistant plastic; a screen-type superheater is provided in the upper part of the main combustion chamber.

[0011] Based on the structure of the heating and treatment device for fine slag fluid in pulverized coal gasification described above, the energy recovery unit is used to heat the air, and the outlet of the energy recovery unit is connected to the main combustion chamber and the secondary combustion chamber.

[0012] Based on the structure of the heating and processing device for fine slag fluid from pulverized coal gasification described above, a primary air inlet and a secondary air inlet are respectively provided at the bottom of the main combustion chamber. The primary air inlet and the secondary air inlet are located in the lower middle part of the main combustion chamber and are positioned at different heights. A tertiary air inlet is provided on the feed inlet of the secondary combustion chamber. The primary air inlet, the secondary air inlet and the tertiary air inlet are respectively connected to the air outlet of the energy recovery unit through pipelines.

[0013] Based on the structure of the heating and treatment device for fine slag fluid from pulverized coal gasification described above, a medium-temperature superheater, a low-temperature superheater, a high-temperature economizer, a high-temperature air preheater, a low-temperature economizer, and a low-temperature air preheater are sequentially arranged in the tail shaft flue; the high-temperature air preheater and the low-temperature air preheater form an energy recovery section, and the high-temperature air preheater and the low-temperature air preheater are connected in series.

[0014] Based on the structure of the heating and treatment device for fine slag fluid in pulverized coal gasification described above, two primary cyclone separators, two secondary cyclone separators, two secondary combustion chambers, and two vertical flues are provided. The main combustion chamber is connected to one primary cyclone separator, one secondary cyclone separator, one secondary combustion chamber, and one vertical flue to form a combustion path.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: (1) This scheme uses the main combustion chamber to burn the fine slag after pulverized coal gasification, and uses the energy recovery section to recover the energy in the tail gas and charge it into the main combustion chamber for secondary use, which reduces the energy demand during the overall combustion. At the same time, the secondary combustion chamber is used to burn the material again, which maximizes the resource utilization of the fine slag after pulverized coal gasification. The cyclone separator separates the solid particles and the gas, and the solid particles return to the main combustion chamber for combustion, so that the fine slag after pulverized coal gasification is burned more completely. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention.

[0017] Figure 2 This is a layout diagram of the present invention; Attached reference numerals: 1. Main combustion chamber; 2. Screen-type superheater; 3. Inlet flue of primary cyclone separator; 4. Primary cyclone separator; 5. Primary return feeder; 6. Secondary combustion chamber; 7. Secondary cyclone separator; 8. Secondary return feeder; 9. Medium-temperature superheater; 10. Low-temperature superheater; 11. High-temperature economizer; 12. High-temperature air preheater; 13. Low-temperature economizer; 14. Low-temperature air preheater; 15. Buffer silo; 16. Primary air inlet; 17. Secondary air inlet; 18. Tertiary air inlet. Detailed Implementation

[0018] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0019] Any feature disclosed in this specification (including any appended claims and abstract) may be replaced by other equivalent or similar features, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0020] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a predetermined orientation, or be constructed and operated in a predetermined orientation. Therefore, they should not be construed as limitations on this invention.

[0021] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0022] Example 1 like Figures 1-2 As shown, the present invention provides a technical solution: A heating and treatment device for fine slag fluid from pulverized coal gasification includes a main combustion chamber 1, a secondary combustion chamber 6, and a vertical flue. Cyclone separators are installed between the main combustion chamber 1 and the secondary combustion chamber 6, and between the secondary combustion chamber 6 and the vertical flue. The return section of the cyclone separator is connected to the main combustion chamber 1. An energy recovery section is also installed in the vertical flue, which is connected to the main combustion chamber 1. The fuel in the main combustion chamber 1 is the fine slag produced after pulverized coal gasification.

[0023] Based on the above structure, this scheme uses the main combustion chamber 1 to burn the fine slag after pulverized coal gasification. The energy recovery unit recovers the energy from the exhaust gas and feeds it back into the main combustion chamber 1 for secondary utilization, reducing the overall energy demand during combustion. At the same time, a secondary combustion chamber 6 is used to re-burn the material, maximizing the resource utilization of the fine slag after pulverized coal gasification. A cyclone separator separates the solid particles and gas, and the solid particles return to the main combustion chamber 1 for combustion, making the combustion of the fine slag after pulverized coal gasification more complete.

[0024] As an example, the cyclone separator between the main combustion chamber 1 and the secondary combustion chamber 6 is a primary cyclone separator 4, and the cyclone separator between the secondary combustion chamber 6 and the vertical flue is a secondary cyclone separator 7; the feed port for the fine slag produced after pulverized coal gasification is set on the inlet flue 3 of the primary cyclone separator, and a buffer silo 15 is set above the feed port.

[0025] Based on the above structure, the fine slag produced after pulverized coal gasification is fed into the inlet flue 3 of the first-stage cyclone separator. This allows the fine slag to be separated once in the first-stage cyclone separator 4. Then, the large particles are fed into the main combustion chamber 1 from the bottom of the first-stage cyclone separator 4 for combustion. By setting up a buffer silo 15, the fine slag can be efficiently fed into the first-stage cyclone separator 4, avoiding excessive amounts.

[0026] As an example, a primary return feeder 5 is provided at the bottom of the primary cyclone separator 4, and a secondary return feeder 8 is provided at the bottom of the secondary cyclone separator 7; both the primary return feeder 5 and the secondary return feeder 8 are connected to the bottom of the main combustion chamber 1.

[0027] Based on the above structure, the return feeders of both stages of the cyclone separator are connected to the main combustion chamber 1, and the material collected by the cyclone separator is recycled and burned again, realizing automated and efficient combustion operation.

[0028] As an example, the feed inlet of the secondary combustion chamber 6 is connected to the air outlet of the primary cyclone separator 4, and the discharge outlet of the secondary combustion chamber 6 is connected to the air inlet of the secondary cyclone separator 7.

[0029] Based on the above structure, efficient connection of the primary cyclone separator 4, the secondary cyclone separator 7, the main combustion chamber 1, and the secondary combustion chamber 6 can be achieved, enabling efficient utilization of the fine slag produced after pulverized coal gasification.

[0030] As an example, the secondary combustion chamber 6 has a U-shaped structure. The U-shaped secondary combustion chamber 6 is surrounded by a membrane wall, and the medium inside the pipe is a mixture of gas and water. This can prolong the time that the material spends in the secondary combustion chamber 6 and achieve complete combustion as much as possible.

[0031] As an example, the main combustion chamber 1 has a rectangular cross-section, and the inner surfaces of all four walls of the main combustion chamber 1 are covered with wear-resistant plastic.

[0032] As an example, a screen-type superheater 2 is provided in the upper part of the main combustion chamber 1. As an example, the energy recovery unit is used to heat the air, and the outlet of the energy recovery unit is connected to the main combustion chamber 1 and the secondary combustion chamber 6. Based on the above structure, the energy of the exhaust gas is recovered through the energy recovery unit to heat the air. The heated gas is fed into the main combustion chamber 1 and the secondary combustion chamber 6, which can reduce the overall energy input and make the combustion in the main combustion chamber 1 and the secondary combustion chamber 6 more complete.

[0033] As an example, a primary air inlet 16 and a secondary air inlet 17 are respectively provided at the bottom of the main combustion chamber 1. The primary air inlet 16 and the secondary air inlet 17 are located in the lower middle part of the main combustion chamber 1, and the primary air inlet 16 and the secondary air inlet 17 are set at different heights.

[0034] A tertiary air inlet 18 can be provided on the feed inlet of the secondary combustion chamber 6.

[0035] The primary air inlet 16, the secondary air inlet 17, and the tertiary air inlet 18 are connected to the air outlet of the energy recovery unit through pipelines.

[0036] Based on the above structure, since there are more fine slags in the main combustion chamber 1, in order to efficiently agitate the materials and achieve complete combustion, two air inlets are set in the middle and lower part of the main combustion chamber 1; at the same time, an air inlet is set on the feed port of the secondary combustion chamber 6, on the one hand to provide power for the materials in the secondary combustion chamber 6, and on the other hand to feed in heat flow to make the combustion more complete.

[0037] As an example, the tail shaft flue is provided with a medium-temperature superheater 9, a low-temperature superheater 10, a high-temperature economizer 11, a high-temperature air preheater 12, a low-temperature economizer 13, and a low-temperature air preheater 14 in sequence; the high-temperature air preheater 12 and the low-temperature air preheater 14 form an energy recovery section, and the high-temperature air preheater 12 and the low-temperature air preheater 14 are connected in series.

[0038] Based on the above structure, air preheating can be achieved more efficiently through the secondary air preheater, which on the one hand increases the energy recovery efficiency of exhaust gas, and on the other hand allows the main combustion chamber 1 and the secondary combustion chamber 6 to burn more completely.

[0039] As an example, there are two primary cyclone separators 4, two secondary cyclone separators 7, two secondary combustion chambers 6, and two vertical flues. The main combustion chamber 1 is connected to one primary cyclone separator 4, one secondary cyclone separator 7, one secondary combustion chamber 6, and one vertical flue to form a combustion path.

[0040] Based on the above structure, this scheme can make combustion more complete and efficient by setting two combustion paths. This scheme can adapt to the direct incineration of fine slag from pulverized coal gasifiers with high moisture content and achieve good combustion effect.

[0041] This design adopts a two-stage combustion (main combustion chamber + secondary combustion chamber) + two-stage separation (primary cyclone separator + secondary cyclone separator); the gasification fine slag feed port is located on the inlet flue of the primary cyclone separator; the main combustion chamber is connected to the secondary combustion chamber through the primary cyclone separator; the secondary combustion chamber is connected to the tail shaft flue through the secondary cyclone separator; the secondary combustion chamber adopts a U-shaped structure; the gasification fine slag separated by the primary and secondary cyclone separators is returned to the main combustion chamber through the primary and secondary return feeders respectively; this invention can adapt to the direct combustion of fine slag from pulverized coal gasification furnaces with high moisture content, and achieve good combustion effect.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A heating and treatment apparatus for fine slag fluid from pulverized coal gasification, characterized in that, It includes a main combustion chamber (1), a secondary combustion chamber (6) and a vertical flue; a cyclone separator is provided between the main combustion chamber (1) and the secondary combustion chamber (6), and between the secondary combustion chamber (6) and the vertical flue. The return section of the cyclone separator is connected to the main combustion chamber (1). An energy recovery section is also provided in the vertical flue. The energy recovery section is connected to the main combustion chamber (1). The fuel of the main combustion chamber (1) is the fine slag produced after pulverized coal gasification.

2. The heating and treatment device for fine slag fluid from pulverized coal gasification according to claim 1, characterized in that: The cyclone separator between the main combustion chamber (1) and the secondary combustion chamber (6) is a first-stage cyclone separator (4), and the cyclone separator between the secondary combustion chamber (6) and the vertical shaft flue is a second-stage cyclone separator (7). The feed port for the fine slag produced after pulverized coal gasification is set on the inlet flue (3) of the first-stage cyclone separator, and a buffer silo (15) is set above the feed port.

3. The heating and treatment device for fine slag fluid from pulverized coal gasification according to claim 2, characterized in that: The bottom of the primary cyclone separator (4) is provided with a primary return feeder (5), and the bottom of the secondary cyclone separator (7) is provided with a secondary return feeder (8); both the primary return feeder (5) and the secondary return feeder (8) are connected to the bottom of the main combustion chamber (1).

4. The heating and treatment device for fine slag fluid from pulverized coal gasification according to claim 3, characterized in that: The feed inlet of the secondary combustion chamber (6) is connected to the air outlet of the primary cyclone separator (4), and the discharge outlet of the secondary combustion chamber (6) is connected to the air inlet of the secondary cyclone separator (7).

5. The heating and treatment apparatus for fine slag fluid from pulverized coal gasification according to any one of claims 1 to 4, characterized in that: The secondary combustion chamber (6) is U-shaped in shape. The U-shaped secondary combustion chamber (6) is surrounded by a membrane wall, and the medium inside the pipe is a mixture of steam and water.

6. The heating and treatment apparatus for fine slag fluid from pulverized coal gasification according to any one of claims 1 to 4, characterized in that: The main combustion chamber (1) has a rectangular cross-section, and the inner surfaces of the four walls of the main combustion chamber (1) are all covered with wear-resistant plastic; a screen-type superheater (2) is provided in the upper part of the main combustion chamber (1).

7. The heating and treatment apparatus for fine slag fluid from pulverized coal gasification according to any one of claims 1 to 4, characterized in that: The energy recovery unit is used to heat the air, and the outlet of the energy recovery unit is connected to the main combustion chamber (1) and the secondary combustion chamber (6).

8. The heating and treatment apparatus for fine slag fluid from pulverized coal gasification according to claim 7, characterized in that: The main combustion chamber (1) is provided with a primary air inlet (16) and a secondary air inlet (17) at the bottom. The primary air inlet (16) and the secondary air inlet (17) are located in the middle and lower part of the main combustion chamber (1) and are located at different heights. The secondary air inlet (16) and the secondary air inlet (17) are provided with a tertiary air inlet (18) at the feed inlet of the secondary combustion chamber (6). The primary air inlet (16), the secondary air inlet (17) and the tertiary air inlet (18) are respectively connected to the air outlet of the energy recovery unit through pipelines.

9. A heating and treatment apparatus for fine slag fluid from pulverized coal gasification according to any one of claims 1 to 4, characterized in that: The tail shaft flue is provided with a medium-temperature superheater (9), a low-temperature superheater (10), a high-temperature economizer (11), a high-temperature air preheater (12), a low-temperature economizer (13), and a low-temperature air preheater (14) in sequence; the high-temperature air preheater (12) and the low-temperature air preheater (14) form an energy recovery section, and the high-temperature air preheater (12) and the low-temperature air preheater (14) are connected in series.

10. The heating and treatment apparatus for fine slag fluid from pulverized coal gasification according to claim 7, characterized in that: The primary cyclone separator (4), secondary cyclone separator (7), secondary combustion chamber (6) and vertical flue are each configured as two. The main combustion chamber (1) is connected to one primary cyclone separator (4), secondary cyclone separator (7), secondary combustion chamber (6) and vertical flue to form a combustion path.

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