Feed system and anti-blocking method of coal water slurry gasification process

Abstract

The present application relates to a kind of water coal slurry gasification process feed system and anti-blocking method, the present application adopts the balanced distribution technology of internal and external coal slurry passage of branch flow and throttling component combination, can when the flow of outside coal slurry passage is too low (when the flow of outside coal slurry passage is low to 10%~40% of normal flow value), trigger to open protection nitrogen gas bypass, nitrogen flow is maintained 100~1000Nm 3 / h at this time, not only can effectively remove the coal slurry remaining in the passage under continuous production state, leave certain buffer time for production adjustment, but also can effectively prevent high temperature crude synthesis gas (1100~1300℃) in gasifier from backflowing into burner and connecting pipeline to avoid burner and connecting pipeline from being damaged due to strong heat action, to achieve the purpose of protecting burner. That is, through the nitrogen purging system provided by the present application, the risk of triggering interlock shutdown when the flow of outside coal slurry passage is too low can be effectively prevented, and low-flow high-pressure nitrogen gas is used to protect the gasifier device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal water slurry gasification process, and particularly relates to a feeding system of coal water slurry gasification process and a method for preventing blockage. BACKGROUND

[0002] The SE coal water slurry gasification furnace is provided with a process burner at the top of the gasification furnace. High-pressure oxygen and coal water slurry are mixed at the nozzle at the end of the gasification burner through the central oxygen channel, the annular oxygen channel and the inner and outer coal water slurry channels of the process burner. The process burner adopts four channels, two of which are used for coal slurry feeding, and the other two are used for oxygen feeding. The outer coal water slurry channel can be used to separately treat substances such as wastewater, oil sludge and waste slurry which are not easy to be slurried with coal.

[0003] Because the coal water slurry is prone to blockage during feeding, the gasification furnace cannot operate normally. If the gasification furnace continues to operate when the outer coal slurry channel is below the safety limit, the burners and conveying pipelines without cold medium protection will be damaged due to bearing strong heat.

[0004] In the existing coal water slurry device, the coal slurry nitrogen blowing structure is arranged on the coal slurry channel header. When the inner and outer coal slurry conveying and distribution are unbalanced, the outer coal slurry flow is too low or blockage occurs, immediate shutdown is required, which leads to forced stop of production and causes great economic loss. SUMMARY

[0005] The first technical problem to be solved by the present application is to provide a feeding system of coal water slurry gasification process which can eliminate the blockage problem of the outer coal slurry channel in the continuous production state and avoid the loss caused by shutdown according to the status of the prior art.

[0006] The second technical problem to be solved by the present application is to provide a method for preventing blockage of the feeding system of coal water slurry gasification process which can eliminate the blockage problem of the outer coal slurry channel in the continuous production state and avoid the loss caused by shutdown according to the status of the prior art.

[0007] The technical scheme adopted by the present application to solve at least one of the above technical problems is as follows:

[0008] The application discloses a feeding system of a coal water slurry gasification process, which comprises a gasification furnace process burner and a coal slurry feeding pipeline, wherein the gasification furnace process burner is provided with an inner coal slurry channel and an outer coal slurry channel; the coal slurry feeding pipeline is provided with a first pipeline for feeding the inner coal slurry channel and a second pipeline for feeding the outer coal slurry channel; the second pipeline is provided with a first flow detection structure for detecting flow and a first cut-off valve for controlling whether the material flows or not; the second pipeline is further connected with a first high-pressure nitrogen blowing pipeline located downstream of the first cut-off valve; the first high-pressure nitrogen blowing pipeline is provided with a second cut-off valve and a cross line across the second cut-off valve; the cross line is provided with a third cut-off valve; and the first flow detection structure, the first cut-off valve, the second cut-off valve and the third cut-off valve are electrically connected with a controller.

[0009] Preferably, the first pipeline is provided with a second flow detection structure for detecting flow and a fourth cut-off valve for controlling whether the material flows or not.

[0010] Preferably, the first pipeline is connected with a second high-pressure nitrogen blowing pipeline, and the connection position of the second high-pressure nitrogen blowing pipeline and the first pipeline is located between the second flow detection structure and the fourth cut-off valve; and the second high-pressure nitrogen blowing pipeline is provided with a fifth cut-off valve.

[0011] Preferably, the coal slurry feeding pipeline is provided with a feeding pump for providing power for feeding; and the second pipeline is provided with a coal slurry resistance component upstream of the first cut-off valve for reducing fluid flow; the feeding power of the feeding pump and the coal slurry resistance component can be matched to regulate the flow ratio of the inner coal slurry channel and the outer coal slurry channel; however, the regulation mode is influenced by the structure of the coal slurry resistance component, and the regulation of the two flow paths is fixed, which is not flexible; the application can further input small flow nitrogen through the second high-pressure nitrogen blowing pipeline to make the regulation of the two flow paths more flexible.

[0012] Preferably, the coal slurry feeding pipeline is provided with a third flow detection structure and a total material cut-off valve.

[0013] Preferably, the third flow detection structure comprises two groups of interval arranged flow meters; and the total material cut-off valve is located downstream of the third flow detection structure.

[0014] Preferably, the first flow detection structure comprises three groups of interval arranged flow meters.

[0015] Preferably, the second flow detection structure comprises one group of interval arranged flow meters.

[0016] A method for preventing blockage of a feeding system of a coal water slurry gasification process, which comprises the following steps:

[0017] The coal slurry feeding pipeline inputs the coal slurry into the inner coal slurry passage of the process burner of the gasification furnace through a first pipeline and into the outer coal slurry passage of the process burner of the gasification furnace through a second pipeline;

[0018] When the first flow detection structure detects that the flow in the second pipeline is lower than a set value, it is determined that partial material accumulation occurs in the second pipeline, the first cut-off valve and the second cut-off valve are closed, the third cut-off valve is opened, and the high-pressure nitrogen gas of the first high-pressure nitrogen gas blowing pipeline is input into the second pipeline through a cross line at a small flow rate to dredge the accumulated material; at this time, the first pipeline keeps feeding into the inner coal slurry passage;

[0019] When the first flow detection structure detects that the flow in the second pipeline meets the requirements, it is determined that the material in the second pipeline has been dredged, the first cut-off valve is opened, the second cut-off valve and the third cut-off valve are closed, and the second pipeline is restored to feeding into the outer coal slurry passage; at this time, the first pipeline also keeps the feeding state into the inner coal slurry passage.

[0020] Preferably, in the state of blowing the accumulated material in the second pipeline with the high-pressure nitrogen gas of the first high-pressure nitrogen gas blowing pipeline through the cross line, the flow rate of the blowing high-pressure nitrogen gas is 100-1000 Nm 3 / h, so as to prevent the high-temperature crude synthesis gas (1100-1300℃) in the gasification furnace from backflowing into the burner and the connecting pipeline.

[0021] Compared with the prior art, the present application has the advantages that: the present application adopts the inner-outer coal slurry passage balanced distribution technology combined with branch flow and throttling components, which can trigger the opening of the protection nitrogen gas bypass when the flow in the outer coal slurry passage is too low (when the flow in the outer coal slurry passage is low to 10%-40% of the normal flow value), at this time, the nitrogen flow is maintained at 100-1000 Nm 3 / h, which not only effectively removes the residual coal slurry in the passage to leave a certain buffer time for production adjustment in the continuous production state, but also effectively prevents the high-temperature crude synthesis gas (1100-1300℃) in the gasification furnace from backflowing into the burner and the connecting pipeline, and the small flow rate of the input nitrogen gas can also supplement the material flow in the outer coal slurry passage to prevent dry burning, so as to avoid the damage of the burner and the connecting pipeline due to the strong heat effect, thereby achieving the purpose of protecting the burner. That is, through the nitrogen blowing system provided by the present application, the risk of triggering interlock shutdown when the coal slurry flow in the outer coal slurry passage is too low can be effectively prevented, and the gasification furnace device can be protected by using low-flow high-pressure nitrogen gas. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The process flow chart of the embodiment 1 of the present application. DETAILED DESCRIPTION

[0023] The present application will be further described in detail below with reference to the embodiments of the drawings.

[0024] Embodiment 1

[0025] The feeding system of the coal water slurry gasification process in the embodiment includes a gasifier process burner and a coal slurry feeding pipeline. The gasifier process burner has an inner coal slurry passage and an outer coal slurry passage. The coal slurry feeding pipeline is provided with a first pipeline 1 for feeding the inner coal slurry passage and a second pipeline 2 for feeding the outer coal slurry passage. The second pipeline 2 is provided with a first flow detection structure 10 for detecting flow, a first shut-off valve 100 for controlling whether the material flows or not, and a first high-pressure nitrogen blowing pipeline 01 connected downstream of the first shut-off valve 100. The first high-pressure nitrogen blowing pipeline 01 is provided with a second shut-off valve 200 and a cross line across the second shut-off valve 200. The cross line is provided with a third shut-off valve 300. The first flow detection structure 10, the first shut-off valve 100, the second shut-off valve 200, and the third shut-off valve 300 are electrically connected to a controller. The following flow detection structures and shut-off valves are also electrically connected to the controller.

[0026] The first pipeline 1 is provided with a second flow detection structure 20 for detecting flow and a fourth shut-off valve 400 for controlling whether the material flows or not. The first pipeline 1 is connected with a second high-pressure nitrogen blowing pipeline 02. The connection between the second high-pressure nitrogen blowing pipeline 02 and the first pipeline 1 is located between the second flow detection structure 20 and the fourth shut-off valve 400. The second high-pressure nitrogen blowing pipeline 02 is provided with a fifth shut-off valve 500.

[0027] The coal slurry feeding pipeline is provided with a feeding pump for providing power for feeding. The second pipeline 2 is provided with a coal slurry resistance component 3 upstream of the first shut-off valve 100 for reducing fluid flow. The feeding power of the feeding pump and the coal slurry resistance component 3 can cooperate to regulate the flow ratio of the inner coal slurry passage and the outer coal slurry passage.

[0028] The coal slurry feeding pipeline is provided with a third flow detection structure 30 and a total material shut-off valve 600. The third flow detection structure 30 includes two groups of flow meters arranged at intervals. The total material shut-off valve is located downstream of the third flow detection structure 30. The first flow detection structure 10 includes three groups of flow meters arranged at intervals. The second flow detection structure 20 includes one group of flow meters arranged at intervals.

[0029] The anti-blocking method of the feeding system of the coal water slurry gasification process in the embodiment includes the following steps:

[0030] The coal slurry feeding pipeline inputs the coal slurry into the inner coal slurry passage of the gasifier process burner through the first pipeline 1 and into the outer coal slurry passage of the gasifier process burner through the second pipeline 2.

[0031] When the first flow detection structure 10 detects that the flow in the second pipeline 2 is lower than the set value, it is determined that partial material accumulation occurs in the second pipeline 2, the first cut-off valve 100 and the second cut-off valve 200 are closed, the third cut-off valve 300 is opened, and the high-pressure nitrogen gas in the first high-pressure nitrogen gas blowing pipeline 01 is input into the second pipeline 2 at a small flow rate through the cross line to dredge the accumulated material; at this time, the first pipeline 1 keeps feeding the inner side coal slurry channel; when the high-pressure nitrogen gas in the first high-pressure nitrogen gas blowing pipeline 01 is input into the second pipeline 2 to dredge the accumulated material, the flow rate of the high-pressure nitrogen gas for blowing is 100-1000 Nm 3 / h, so as to prevent the high-temperature crude synthesis gas at 1100-1300℃ in the gasifier from backflowing into the burner and the connecting pipeline;

[0032] When the first flow detection structure 10 detects that the flow in the second pipeline 2 meets the requirements, it is determined that the material in the second pipeline 2 has been dredged, the first cut-off valve 100 is opened, the second cut-off valve 200 and the third cut-off valve 300 are closed, and the second pipeline 2 returns to the outer side coal slurry channel feeding; at this time, the first pipeline 1 also keeps the inner side coal slurry channel feeding state.

[0033] If serious blockage occurs, the work is stopped, the cut-off valves on the first high-pressure nitrogen gas blowing pipeline 01 and the second high-pressure nitrogen gas blowing pipeline 02 are opened, and high-flow-rate nitrogen gas is used for blowing.

[0034] When the coal slurry amount of the gasifier feeding is 50 m 3 / h, the coal slurry amount of the inner side coal slurry channel is 40-45 m 3 / h (80%-90% of the total coal slurry flow rate of the gasification), and the coal slurry amount of the outer side coal slurry channel is 5-10 m 3 / h (10%-20% of the total coal slurry flow rate of the gasification), when the flow rate of the outer side coal slurry channel is reduced to below 5% of the coal slurry flow rate, it is determined that blockage occurs in the outer side coal slurry channel, at this time, the outer side coal slurry cut-off valve is closed, and the outer side coal slurry channel nitrogen protection cut-off valve is opened, at this time, the nitrogen pressure needs to be higher than the pressure of the gasifier, and the blowing amount of the outer side channel protection nitrogen gas is controlled to be 100-300 Nm 3 / h, so as to prevent the gasifier from stopping. When the blowing amount of the protection nitrogen gas is reduced to 100 Nm 3 / h, at this time, it is indicated that the protection nitrogen gas has not dredged the pipeline, at this time, the stopping program is executed, and high-flow-rate nitrogen gas is used for blowing.

[0035] Example 2:

[0036] The difference between this embodiment and example 1 is that:

[0037] Since the regulation mode of the flow of the first pipeline 1 and the second pipeline 2 in the embodiment 1 is affected by the structure of the coal slurry resistance component 3, the regulation is fixed, that is, in the case of a certain structure of the coal slurry resistance component 3, the control of the flow of the two paths is also certain, which is not flexible enough. When the flow control requirements of the inner coal slurry passage and the outer coal slurry passage are high in actual production, a small flow of nitrogen can be input through the second high-pressure nitrogen blowing pipeline 02 to make the regulation of the flow of the two paths more flexible.

Claims

1. A feed system of a coal water slurry gasification process, comprising a gasifier process burner and a coal slurry feeding pipeline, the gasifier process burner having an inner coal slurry passage and an outer coal slurry passage, the coal slurry feeding pipeline being provided with a first pipeline for feeding the inner coal slurry passage and a second pipeline for feeding the outer coal slurry passage, characterized in that: The second pipeline is provided with a first flow detection structure for detecting flow, a first cut-off valve for controlling whether material flows or not, and a first high-pressure nitrogen blowing pipeline downstream of the first cut-off valve, which is provided with a second cut-off valve and a cross line across the second cut-off valve, and the cross line is provided with a third cut-off valve, and the first flow detection structure, the first cut-off valve, the second cut-off valve and the third cut-off valve are electrically connected with a controller.

2. The feed system for an entrained-flow coal water slurry gasification process according to claim 1, wherein: The first pipeline is provided with a second flow detection structure for detecting flow, and a fourth cut-off valve for controlling whether material flows or not.

3. The feed system for an entrained-flow coal water slurry gasification process of claim 2 wherein: The first pipeline is connected with a second high-pressure nitrogen blowing pipeline, and the connection between the second high-pressure nitrogen blowing pipeline and the first pipeline is located between the second flow detection structure and the fourth cut-off valve, and the second high-pressure nitrogen blowing pipeline is provided with a fifth cut-off valve.

4. The feed system for an entrained-flow coal water slurry gasification process of claim 3 wherein: The coal slurry feeding pipeline is provided with a feeding pump for providing power for feeding, and the second pipeline is provided with a coal slurry resistance component upstream of the first cut-off valve for reducing fluid flow.

5. The feed system for an entrained-flow coal water slurry gasification process of claim 4 wherein: The coal slurry feeding pipeline is provided with a third flow detection structure and a total material cut-off valve.

6. The feed system for an entrained-flow coal water slurry gasification process of claim 5 wherein: The third flow detection structure includes two groups of flow meters arranged at intervals.

7. The feed system for an entrained-flow coal water slurry gasification process according to any one of claims 1 to 6, characterized in that: The first flow detection structure includes three groups of flow meters arranged at intervals.

8. A feed system for an entrained-flow coal water slurry gasification process according to any one of claims 2 to 6, wherein: The second flow detection structure includes one group of flow meters arranged at intervals.

9. A method of preventing plugging in a feed system of a coal water slurry gasification process, characterized by The method comprises the following steps: The coal slurry feeding pipeline inputs coal slurry into the inner coal slurry passage of the gasification furnace process burner through the first pipeline, and into the outer coal slurry passage of the gasification furnace process burner through the second pipeline. When the first flow detection structure detects that the flow in the second pipeline is lower than the set value, it is determined that partial material accumulation occurs in the second pipeline, the first cut-off valve and the second cut-off valve are closed, the third cut-off valve is opened, and the high-pressure nitrogen gas in the first high-pressure nitrogen blowing pipeline is input into the second pipeline through the cross line at a small flow rate to dredge the accumulated material; at this time, the first pipeline remains to feed the inner coal slurry passage. When the first flow detection structure detects that the flow in the second pipeline meets the requirements, it is determined that the material in the second pipeline has been dredged, the first cut-off valve is opened, the second cut-off valve and the third cut-off valve are closed, and the second pipeline is restored to feed the outer coal slurry passage; at this time, the first pipeline also remains in the feeding state of the inner coal slurry passage.

10. The method of claim 9, wherein the method further comprises: providing a water supply to the coal slurry gasification process feed system. The high-pressure nitrogen gas of the first high-pressure nitrogen gas blowing pipeline is input into the second pipeline through the cross line to blow the accumulated material in the unblocked state, and the flow rate of the high-pressure nitrogen gas for blowing is 100-1000 Nm 3 / h, so as to prevent the high-temperature crude synthesis gas at 1100-1300 ℃ in the gasification furnace from backflowing into the burner and the connecting pipeline.

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