Closed scraper, waste alkali incineration system and method for improving alkali ash conveying efficiency

Abstract

The invention belongs to the technical field of waste gas and waste liquid treatment, and discloses a closed scraper machine, a waste alkali incineration system and a method for improving alkali ash conveying efficiency. The scraper conveyor comprises a tube pass, a shell pass, a thermal insulation material, an alkali ash temperature measuring device, a scraper and a crawler belt, a branch flue inlet and / or a branch air duct inlet; and a flue scraper outlet and / or an air duct scraper outlet. On the premise that no extra power source or heat source exists, the alkali ash conveying reliability of the incinerator is improved, the continuous work period is prolonged, and efficient and continuous operation of the whole incineration system is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of waste gas and waste liquid treatment, and more specifically, relates to a closed scraper conveyor and a waste alkali incineration system and a method for improving alkali ash conveying efficiency. Background Art

[0002] A large amount of alkaline waste liquid is produced in the petrochemical, papermaking, printing and other industries, and contains sulfides and organic matter. If it is directly discharged, it will cause serious environmental pollution. At present, high-temperature incineration is a widely used method for treating salt-containing waste liquid. High-temperature incineration refers to the process of decomposing and harmlessly treating organic matter in the incinerated waste. The incineration process consists of gasification, thermal decomposition, and combustion heat transfer processes. According to the requirements of GB18484, the waste to be incinerated is generally incinerated at 1100℃ for more than 2S, so that organic hydrocarbons generate CO2 and H2O, and the residual salt is discharged in a molten state and solid particles.

[0003] The entire process of waste alkali incineration generally includes key equipment such as incinerators, bag filters, air preheaters, dual-axis coolers and crushers for molten salt discharge, and conveyors for alkali ash transportation. Currently, common incinerators include integrated incineration boilers and quenching incinerators. Among them, integrated incineration boilers have the advantages of large scale and high thermal efficiency utilization, which also conforms to the current development trend of large-scale and green, and has become the most widely used incinerator form. Figure 1 As shown, the waste gas and waste liquid are burned at high temperature in the combustion chamber. A part of the molten salt particles gather into molten molten salt and are discharged from the closed molten salt discharge port at the bottom of the furnace and transported to the dissolving tank or baler by a conveyor. Another part of the molten salt particles enter the cooling chamber of the incinerator with the hot flue gas. Part of the molten salt particles in the cooling chamber will fall into the ash collecting trough at the bottom of the cooling chamber due to gravity, and then be transported to the dissolving tank or baler by a conveyor. The other part is discharged from the flue gas outlet of the incinerator into the dust collector. The air is heated by the air preheater and transported to the burner for use as combustion air.

[0004] As a particle with low density and easy to get damp, alkali ash is very susceptible to the external environment. If the sealing effect of the conveyor is not good, firstly, the temperature of the alkali ash in transportation will drop rapidly, causing the alkali ash to get damp and solidify into lumps, forcing the conveyor to stop for cleaning. Secondly, it will cause the alkali ash in the conveyor to leak, thus causing environmental pollution.

[0005] Therefore, in order to address the problems that easily occur during the alkali ash recovery process, it is of great significance to develop an efficient, power-free, and continuously operating alkali ash transportation method. Summary of the invention

[0006] The purpose of the present invention is to address the deficiencies of the prior art and propose a closed scraper and a waste alkali incineration system and a method for improving the efficiency of alkali ash transportation. The present invention improves the reliability and continuous working cycle of alkali ash transportation in the incinerator without additional power source and heat source, and realizes efficient and continuous operation of the entire incineration system.

[0007] In order to achieve the above object, the present invention provides a closed scraper in a first aspect, the scraper comprising:

[0008] Tube side, shell side, alkali ash temperature measuring device, scraper, crawler;

[0009] Branch flue inlet and / or branch air duct inlet; flue scraper outlet and / or air duct scraper outlet;

[0010] The crawler belt is used to realize the circular rolling of the scraper arranged thereon in the pipe passage;

[0011] The tube side is a closed cavity structure, and the cavity size ensures the normal operation of the scraper; the tube side is provided with an alkali ash inlet and an alkali ash outlet;

[0012] The shell side is a hollow shell disposed outside the tube side and completely or partially covering the tube side, or is a coil system consisting of one or more branch pipes;

[0013] The branch flue inlet and the flue scraper outlet are both arranged on the shell side or the tube side;

[0014] The branch air duct inlet and the air duct scraper outlet are both arranged on the shell side or the tube side;

[0015] The flue scraper outlet is connected to a hot flue gas exhaust pipeline; the air duct scraper outlet is connected to a hot air exhaust pipeline.

[0016] According to the present invention, preferably, the branch flue inlet and the branch air duct inlet are both provided with flow regulating devices; the flow regulating device and the alkali ash temperature measuring device are automatically interlocked or manually controlled, so that the flow regulating device can adjust the air intake flow rate according to the measurement result of the alkali ash temperature in the scraper by the alkali ash temperature measuring device. As a preferred solution, when the alkali ash temperature measuring device detects that the alkali ash temperature in the scraper is reduced, the flow of hot flue gas and / or hot air can be increased by the flow regulating device. As a preferred solution, in extreme cases, when the alkali ash temperature measuring device detects that the alkali ash temperature in the scraper is sufficient, the branch flue and / or branch air duct can be closed by the flow regulating device.

[0017] According to the present invention, preferably, the outer wall of the scraper conveyor is evenly covered with insulation material, and the outer wall of the branch flue inlet, the outer wall of the branch air duct inlet, the outer wall of the flue scraper conveyor outlet and the outer wall of the air duct scraper conveyor outlet are also evenly surrounded by the insulation material.

[0018] According to the present invention, preferably, the branch flue inlet and the flue scraper outlet are simultaneously arranged on the shell side or the tube side, the branch flue inlet is arranged close to the alkali ash inlet, and the flue scraper outlet is arranged close to the alkali ash outlet; the branch air duct inlet and the air duct scraper outlet are simultaneously arranged on the shell side or the tube side, the branch air duct inlet is arranged close to the alkali ash inlet, and the air duct scraper outlet is arranged close to the alkali ash outlet;

[0019] The branch flue inlet is used to send the hot flue gas entering the scraper into the tube side and / or the shell side, and together with the flue scraper outlet, it is used to realize the same-direction flow of the hot flue gas and the alkali ash in the tube side; the branch air duct inlet is used to send the hot air entering the scraper into the tube side and / or the shell side, and together with the air duct scraper outlet, it is used to realize the same-direction flow of the hot air and the alkali ash in the tube side. Preferably, the branch flue inlet is used to send the hot flue gas entering the scraper into the tube side, and together with the flue scraper outlet, it is used to realize the same-direction flow of the hot flue gas and the alkali ash in the tube side; the branch air duct inlet is used to send the hot air entering the scraper into the shell side, and together with the air duct scraper outlet, it is used to realize the same-direction flow of the hot air and the alkali ash in the tube side. In the present invention, such a benefit is to avoid the accumulation of ash due to the presence of some alkali ash in the hot flue gas, which is easily caused by long-term circulation in the shell side, and eventually leads to blockage of the shell side.

[0020] According to the present invention, preferably, the branch flue inlet and the flue scraper outlet are simultaneously arranged on the shell side or the tube side, the flue scraper outlet is arranged close to the alkali ash inlet side, and the branch flue inlet is arranged close to the alkali ash outlet side; the branch air duct inlet and the air duct scraper outlet are simultaneously arranged on the shell side or the tube side, the air duct scraper outlet is arranged close to the alkali ash inlet side, and the branch air duct inlet is arranged close to the alkali ash outlet side.

[0021] The branch flue inlet is used to send the hot flue gas entering the scraper into the tube side and / or shell side, and together with the flue scraper outlet, is used to achieve the reverse flow of hot flue gas and alkali ash in the tube side; the branch air duct inlet is used to send the hot air entering the scraper into the tube side and / or shell side, and together with the air duct scraper outlet, is used to achieve the reverse flow of hot air and alkali ash in the tube side. Preferably, the branch flue inlet is used to send the hot flue gas entering the scraper into the shell side, and together with the flue scraper outlet, is used to achieve the reverse flow of hot flue gas and alkali ash in the tube side; the branch air duct inlet is used to send the hot air entering the scraper into the shell side, and together with the air duct scraper outlet, is used to achieve the reverse flow of hot air and alkali ash in the tube side.

[0022] In the present invention, the countercurrent flow is beneficial to increase the heat exchange efficiency.

[0023] According to the present invention, preferably, the shell side is a hollow shell covering the lower half of the tube side.

[0024] In the present invention, the shell side is a coil system composed of one or more branch pipes, which has the advantage of avoiding dead corners and dents existing in the cavity shell side and reducing the pressure loss of hot air.

[0025] The second aspect of the present invention provides a system for incinerating waste alkali, the system comprising an incinerator combustion chamber, an air preheater, a hot air duct, a hot flue gas exhaust duct, a cooling chamber, an ash collection trough, a dust collector, an alkali ash treatment device, a branch flue, a branch air duct and the closed scraper;

[0026] The combustion chamber of the incinerator is used to incinerate waste alkali;

[0027] The hot air duct is used to send the hot air preheated by the air preheater into the combustion chamber of the incinerator;

[0028] The hot flue gas exhaust duct is used to send the hot flue gas exhausted from the combustion chamber of the incinerator into the air preheater to preheat the cold air in the air preheater;

[0029] The ash collecting trough is arranged at the lower part of the cooling chamber; the cooling chamber is used to send the alkaline ash in the hot flue gas preheated by the cold air into the ash collecting trough and to send the hot flue gas preheated by the cold air into the dust collector through the cooling chamber outlet;

[0030] The branch flue is led out from the combustion chamber of the incinerator and is used to send the hot flue gas from the incinerator into the tube side and / or shell side of the closed scraper conveyor through the inlet of the branch flue;

[0031] The branch air duct is led out from the hot air duct and is used to send the hot air from the hot air duct into the tube side and / or shell side of the closed scraper conveyor through the inlet of the branch air duct;

[0032] The hot flue gas exhaust pipeline and the hot air exhaust pipeline are used to respectively deliver the hot flue gas and / or hot air entering the tube side and / or the shell side into the dust collector;

[0033] The alkali ash inlet is connected to at least one of the closed molten salt discharge port of the incinerator combustion chamber, the outlet of the ash collecting tank and the ash discharge port of the dust collector, and the alkali ash outlet is connected to the alkali ash treatment device.

[0034] In the present invention, the "incinerator" mentioned is an industrial waste gas and waste liquid incinerator known to those skilled in the art.

[0035] According to the present invention, preferably, the branch flue is led out from the vicinity of the burner of the combustion chamber of the incinerator and / or the vicinity of the closed molten salt discharge port of the combustion chamber of the incinerator. In the present invention, leading out from the vicinity of the burner can ensure a higher initial temperature of the flue gas, while leading out from the closed molten salt discharge port can allow the molten salt in a molten state to be continuously heated by the high-temperature flue gas, thereby preventing the molten salt from condensing due to a drop in temperature.

[0036] According to the present invention, preferably, the alkali ash treatment device is a dissolving tank and / or a packaging machine.

[0037] The third aspect of the present invention provides a method for improving the efficiency of conveying alkali ash from an incinerator, the method using the system comprising:

[0038] The alkali ash entering the tube from the alkali ash inlet is transported to the alkali ash outlet by a circulating rolling scraper, and enters the alkali ash treatment device;

[0039] The hot flue gas in the combustion chamber of the incinerator and / or the hot air in the hot air duct are respectively sent into the tube side and / or the shell side of the closed scraper conveyor through the branch flue and / or the branch air duct;

[0040] The hot flue gas and / or hot air in the closed scraper conveyor is introduced into the hot flue gas exhaust pipeline and / or hot air exhaust pipeline, and sent to the dust collector together with the remaining flue gas generated in the incinerator combustion chamber discharged from the cooling chamber outlet for dust removal.

[0041] In the present invention, when the incinerator is operating normally, the crawler belt is used to realize the scraper arranged thereon to circulate and roll in the pipe, thereby ensuring the sustainable transportation of alkali ash.

[0042] According to the present invention, preferably, the hot flue gas and / or hot air fed into the tube side and / or shell side of the closed scraper conveyor flows in the same direction as the alkali ash in the tube side, or flows in the opposite direction.

[0043] In the present invention, the hot flue gas and / or hot air fed into the tube side and / or shell side of the closed scraper conveyor flows in the same direction or in the opposite direction to the alkali ash in the tube side, thereby: on the one hand, it plays a role of heating and heat preservation, ensuring that the temperature of the alkali ash in the tube side will not drop; on the other hand, since the hot flue gas and / or hot air finally flows into the dust collector through the hot flue gas exhaust pipeline and / or the hot air exhaust pipeline, a slight negative pressure is formed in the tube side and / or shell side of the closed scraper conveyor, thereby avoiding the occurrence of alkali ash overflow and leakage.

[0044] According to the present invention, preferably, the alkali ash temperature in the pipe pass is controlled to be within a temperature threshold range by adjusting the intake air flow rate; the temperature threshold range is 100°C-1100°C.

[0045] The beneficial effects of the technical solution of the present invention are as follows:

[0046] 1. The present invention innovates the incinerator alkali ash conveying method to realize automatic control of the temperature of the alkali ash conveying process without additional power source and heat source, so as to avoid the alkali ash from getting damp and agglomerating, and improve the stability and efficiency of alkali ash conveying;

[0047] 2. The present invention ensures a micro-negative pressure environment during the alkali ash transportation process, reduces leakage during the alkali ash transportation process, and is beneficial to environmental protection;

[0048] 3. The present invention does not have complex mechanical and electrical devices, which reduces the probability of failure of the device itself;

[0049] 4. The new closed scraper of the present invention has a modular structure, and the transport volume and distance can be adjusted according to the actual situation on site while ensuring that the main structure remains unchanged.

[0050] 5. The present invention provides a simple and economical method for modifying existing incineration facilities with related problems.

[0051] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0053] Figure 1 A schematic diagram of the existing waste alkali incineration and alkali ash transportation process is shown.

[0054] Figure 2 A schematic diagram of a waste alkali incineration system and an alkali ash conveying process provided by the present invention is shown.

[0055] Figure 3 The diagram shows the arrangement of a closed scraper conveyor and a waste alkali incineration system provided by the present invention.

[0056] Figure 4 A front view of a closed scraper provided in Example 1 of the present invention is shown.

[0057] Figure 5 A top view of a closed scraper provided in Example 2 of the present invention is shown.

[0058] The following are the descriptions of the reference numerals:

[0059] 1. Branch flue entrance; 2. Branch air duct entrance; 3. Duct scraper outlet; 4. Flue scraper outlet; 5. Flow control device; 6. Incinerator combustion chamber; 7. Air preheater; 8. Hot air duct; 9. Cooling chamber; 11. Ash collecting trough; 12. Dust collector; 13. Branch flue; 14. Branch air duct; 15. Alkali ash entrance; 16. Alkali ash outlet; 17. Hot flue gas discharge pipeline; 18. Hot air discharge pipeline; 19. Closed scraper; 21. Cold air; 22. Hot flue gas at the cooling chamber outlet; 23. Closed molten salt discharge port; 24. Dissolution tank; 25. Alkali ash; 26. Conveyor;

[0060] 10. Tube side; 20. Shell side; 30. Insulation material; 40. Scraper; 50. Alkali ash temperature measuring device; 60. Track. DETAILED DESCRIPTION

[0061] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0062] Example 1

[0063] This embodiment provides a closed scraper machine, such as Figure 2 , 4 As shown, the scraper comprises:

[0064] Tube side 10, shell side 20, insulation material 30, alkali ash temperature measuring device 50, scraper 40, crawler belt 60;

[0065] Branch flue inlet 1 and branch air duct inlet 2; flue scraper outlet 4 and air duct scraper outlet 3;

[0066] The crawler belt 60 is used to realize the cyclic rolling of the scraper 40 disposed thereon in the pipe 10;

[0067] The tube side 10 is a closed cavity structure, and the cavity size ensures the normal operation of the scraper 40; the tube side 10 is provided with an alkali ash inlet 15 and an alkali ash outlet 16;

[0068] The shell side 20 is a hollow shell covering the lower half of the tube side 10;

[0069] The heat-insulating material 30 evenly covers the entire outer wall of the scraper;

[0070] The branch flue inlet 1 and the flue scraper outlet 4 are both arranged on the tube side 10, the branch flue inlet 1 is arranged close to the alkali ash inlet 15, and the flue scraper outlet 4 is arranged close to the alkali ash outlet 16; the branch flue inlet 1 is used to send the hot flue gas entering the scraper into the tube side 10, and together with the flue scraper outlet 4, is used to realize the same direction flow of hot flue gas and alkali ash in the tube side 10;

[0071] The branch duct inlet 2 and the duct scraper outlet 3 are both arranged on the shell side 20, the branch duct inlet 2 is arranged close to the alkali ash inlet 15, and the duct scraper outlet 3 is arranged close to the alkali ash outlet 16; the branch duct inlet 2 is used to send the hot air entering the scraper into the shell side, and together with the duct scraper outlet 3, is used to realize the same direction flow of hot air and alkali ash in the tube side 10;

[0072] The branch flue inlet 1 and the branch air duct inlet 2 are both provided with a flow regulating device 5; the flow regulating device 5 is automatically interlocked with the alkali ash temperature measuring device 50, so that the flow regulating device 5 can adjust the intake air flow rate according to the measurement result of the alkali ash temperature in the scraper conveyor by the alkali ash temperature measuring device 50.

[0073] The flue scraper outlet 4 is connected to a hot flue gas exhaust pipeline 17 ; the air duct scraper outlet 3 is connected to a hot air exhaust pipeline 18 .

[0074] The outer wall of the branch flue inlet 1, the outer wall of the branch air duct inlet 2, the outer wall of the flue scraper outlet 4 and the outer wall of the air duct scraper outlet 3 are also uniformly surrounded by the thermal insulation material 30.

[0075] This embodiment also provides a system for incinerating waste alkali, such as Figure 2 , 3 As shown, the system includes an incinerator combustion chamber 6, an air preheater 7, a hot air duct 8, a hot flue gas exhaust duct, a cooling chamber 9, an ash collecting trough 11, a dust collector 12, an alkali ash treatment device, a branch flue 13, a branch air duct 14 and the above-mentioned closed scraper 19;

[0076] The incinerator combustion chamber 6 is used to incinerate waste alkali;

[0077] The hot air duct 8 is used to deliver the hot air preheated by the air preheater 7 into the combustion chamber 6 of the incinerator;

[0078] The hot flue gas exhaust duct (not shown) is used to send the hot flue gas exhausted from the incinerator combustion chamber 6 into the air preheater 7 to preheat the cold air 21 in the air preheater 7; the cold air 21 enters the air preheater 7 from the external environment.

[0079] The ash collecting trough 11 is arranged at the lower part of the cooling chamber 9; the cooling chamber 9 is used to send the alkaline ash in the hot flue gas after being preheated by the cold air 7 into the ash collecting trough 11 and to send the hot flue gas after being preheated by the cold air into the dust collector through the cooling chamber outlet;

[0080] The branch flue 13 is led out from the vicinity of the burner of the combustion chamber of the incinerator, and is used to send the hot flue gas from the incinerator into the tube 10 of the closed scraper conveyor through the branch flue inlet 1;

[0081] The branch air duct 14 is led out from the hot air duct and is used to send the hot air from the hot air duct into the shell side 20 of the closed scraper conveyor through the branch air duct inlet;

[0082] The hot flue gas exhaust pipeline 17 and the hot air exhaust pipeline 18 are used to respectively deliver the hot flue gas and hot air entering the tube side 10 and the shell side 20 into the dust collector 12;

[0083] The alkaline ash inlet 15 is connected to the outlet of the ash collecting tank 11 , and the alkaline ash outlet 16 is connected to the dissolution tank 24 .

[0084] This embodiment adopts the above system to transport the incinerator alkali ash, which improves the transportation efficiency. The specific transportation method includes:

[0085] The alkali ash 25 entering the tube side 10 from the alkali ash inlet 15 is transported to the alkali ash outlet 16 by a circulating rolling scraper 40 and enters the dissolving tank 24;

[0086] The hot flue gas in the combustion chamber 6 of the incinerator and the hot air in the hot air duct 8 are respectively sent into the tube side 10 and the shell side 20 of the closed scraper through the branch flue 13 and the branch air duct 14, and flow in the same direction as the alkali ash 25 in the tube side 10; the alkali ash temperature in the tube side 10 is controlled within the temperature threshold range by adjusting the air intake flow rate 5; the temperature threshold range is 250°C.

[0087] The hot flue gas and hot air in the closed scraper 19 are respectively introduced into the hot flue gas exhaust pipeline 17 and the hot air exhaust pipeline 18, and sent to the dust collector 12 together with the remaining flue gas generated in the incinerator combustion chamber discharged from the cooling chamber outlet for dust removal.

[0088] Example 2

[0089] This embodiment provides a closed scraper machine, such as Figure 2 , 5 As shown, the difference between the scraper machine of this embodiment and embodiment 1 is only that:

[0090] The shell side 20 is a coil system composed of multiple branch pipes, which has the advantage of avoiding dead corners and bumps in the cavity shell side, reducing the pressure loss of hot air, and avoiding dead corners and bumps, thereby avoiding the phenomenon of granular alkali ash gathering and clogging in dead corners.

[0091] The branch flue inlet 1 and the flue scraper outlet 4 are both arranged on the shell side 20, the flue scraper outlet 4 is arranged close to the alkali ash inlet 15, and the branch flue inlet 1 is arranged close to the alkali ash outlet 16; the branch flue inlet 1 is used to send the hot flue gas entering the scraper into the shell side 20, and together with the flue scraper outlet 4, is used to achieve the reverse flow of hot flue gas and alkali ash in the tube side 10;

[0092] The branch duct inlet 2 and the duct scraper outlet 3 are simultaneously arranged on the pipe line 10, the duct scraper outlet 3 is arranged close to the alkali ash inlet 15, and the branch duct inlet 2 is arranged close to the alkali ash outlet 16; the branch duct inlet 2 is used to send the hot air entering the scraper into the pipe line 10, and together with the duct scraper outlet 3, is used to realize the reverse flow of hot air and alkali ash in the pipe line 10.

[0093] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A closed scraper, It is characterized in that The scraper comprises: Tube side, shell side, alkali ash temperature measuring device, scraper, crawler; Branch flue inlet and / or branch air duct inlet; flue scraper outlet and / or air duct scraper outlet; The crawler belt is used to realize the circular rolling of the scraper arranged thereon in the pipe passage; The tube side is a closed cavity structure, and the cavity size ensures the normal operation of the scraper; the tube side is provided with an alkali ash inlet and an alkali ash outlet; The shell side is a hollow shell disposed outside the tube side and completely or partially covering the tube side, or is a coil system consisting of one or more branch pipes; The branch flue inlet and the flue scraper outlet are both arranged on the shell side or the tube side; The branch air duct inlet and the air duct scraper outlet are both arranged on the shell side or the tube side; The flue scraper outlet is connected to a hot flue gas exhaust pipeline; the air duct scraper outlet is connected to a hot air exhaust pipeline.

2. The enclosed scraper according to claim 1, in, The branch flue inlet and the branch air duct inlet are both provided with flow regulating devices; the flow regulating devices are automatically interlocked or manually controlled with the alkali ash temperature measuring device, so that the flow regulating devices can adjust the air intake flow rate according to the measurement result of the alkali ash temperature in the scraper conveyor by the alkali ash temperature measuring device.

3. The enclosed scraper according to claim 1, in, The outer wall of the scraper is evenly covered with insulation material, and the outer wall of the branch flue inlet, the outer wall of the branch air duct inlet, the outer wall of the flue scraper outlet and the outer wall of the air duct scraper outlet are also evenly surrounded by insulation material.

4. The enclosed scraper according to claim 1, in, The branch flue inlet and the flue scraper outlet are both arranged on the shell side or the tube side, the branch flue inlet is arranged close to the alkali ash inlet, and the flue scraper outlet is arranged close to the alkali ash outlet; The branch duct inlet and the duct scraper outlet are simultaneously arranged on the shell side or the tube side, the branch duct inlet is arranged close to the alkali ash inlet side, and the duct scraper outlet is arranged close to the alkali ash outlet side.

5. The enclosed scraper according to claim 1, in, The branch flue inlet and the flue scraper outlet are both arranged on the shell side or the tube side, the flue scraper outlet is arranged close to the alkali ash inlet, and the branch flue inlet is arranged close to the alkali ash outlet; The branch duct inlet and the duct scraper outlet are simultaneously arranged on the shell side or the tube side, the duct scraper outlet is arranged close to the alkali ash inlet side, and the branch duct inlet is arranged close to the alkali ash outlet side.

6. The enclosed scraper according to claim 1, in, The shell side is a hollow shell covering the lower half of the tube side.

7. A system for incineration of spent alkali, It is characterized in that The system comprises an incinerator combustion chamber, an air preheater, a hot air duct, a hot flue gas exhaust duct, a cooling chamber, an ash collecting trough, a dust collector, an alkali ash treatment device, a branch flue, a branch air duct and a closed scraper according to any one of claims 1 to 6; The combustion chamber of the incinerator is used to incinerate waste alkali; The hot air duct is used to send the hot air preheated by the air preheater into the combustion chamber of the incinerator; The hot flue gas exhaust duct is used to send the hot flue gas exhausted from the combustion chamber of the incinerator into the air preheater to preheat the cold air in the air preheater; The ash collecting trough is arranged at the lower part of the cooling chamber; the cooling chamber is used to send the alkaline ash in the hot flue gas preheated by the cold air into the ash collecting trough and to send the hot flue gas preheated by the cold air into the dust collector through the cooling chamber outlet; The branch flue is led out from the combustion chamber of the incinerator and is used to send the hot flue gas from the incinerator into the tube side and / or shell side of the closed scraper conveyor through the inlet of the branch flue; The branch air duct is led out from the hot air duct and is used to send the hot air from the hot air duct into the tube side and / or shell side of the closed scraper conveyor through the inlet of the branch air duct; The hot flue gas exhaust pipeline and the hot air exhaust pipeline are used to respectively deliver the hot flue gas and / or hot air entering the tube side and / or the shell side into the dust collector; The alkali ash inlet is connected to at least one of the closed molten salt discharge port of the incinerator combustion chamber, the outlet of the ash collecting tank and the ash discharge port of the dust collector, and the alkali ash outlet is connected to the alkali ash treatment device.

8. The system for incineration of spent alkali according to claim 7, in, The branch flue is led out from the vicinity of the burner of the combustion chamber of the incinerator and / or the vicinity of the closed molten salt discharge port of the combustion chamber of the incinerator; The alkali ash treatment device is a dissolving tank and / or a packaging machine.

9. A method for improving the efficiency of conveying alkali ash from an incinerator. It is characterized in that The method adopts the system of claim 7 or 8, comprising: The alkali ash entering the tube from the alkali ash inlet is transported to the alkali ash outlet by a circulating rolling scraper, and enters the alkali ash treatment device; The hot flue gas in the combustion chamber of the incinerator and / or the hot air in the hot air duct are respectively sent into the tube side and / or the shell side of the closed scraper conveyor through the branch flue and / or the branch air duct; The hot flue gas and / or hot air in the closed scraper conveyor is introduced into the hot flue gas exhaust pipeline and / or hot air exhaust pipeline, and sent to the dust collector together with the remaining flue gas generated in the incinerator combustion chamber discharged from the cooling chamber outlet for dust removal.

10. The method for improving the efficiency of conveying alkali ash from an incinerator according to claim 9, in, The hot flue gas and / or hot air fed into the tube side and / or shell side of the closed scraper conveyor flows in the same direction as the alkali ash in the tube side, or flows in the opposite direction; The alkali ash temperature in the pipe is controlled to be within a temperature threshold range by adjusting the intake air flow; the temperature threshold range is 100°C-1100°C.

Images