CN115502183B - A suspension roasting device for dechlorinating fly ash to produce two products and its use method - Google Patents

Abstract

The invention provides a suspension roasting device for producing two products by dechlorination of fly ash and a use method thereof, and relates to the technical field of metallurgy. The suspension roasting device comprises a feeding system, a roasting system, a cooling system, a flue gas dust removal system and a flue gas dechlorination purification system, and further comprises a feed bin, an electronic quantitative feeder, a dryer, a flue gas cut-off valve, an air valve I, a cyclone preheater, a gate valve, a roasting main furnace, a cyclone separator, a stay tank, a combustor, a pneumatic conveying pump II, a cyclone cooler, a final cooler, a pneumatic conveying pump I, a dust remover, a ash returning conveyor, an ash bin, an ash returning impeller, a water washing tower, a neutralization tower, a plate leaf valve, an exhaust fan, a chimney and the like. The invention can produce two products, namely a fly ash roasting product and a fly ash drying product by using the same device and the same fuel and only changing the operation flow of the device and adjusting the temperature parameters.

Description

A suspension roasting device for dechlorinating fly ash to produce two products and its use method

Technical field

The invention relates to the field of metallurgical technology, and in particular to a suspension roasting device for dechlorinating fly ash to produce two products and a method of use.

Background technique

In the 1970s, the global energy crisis, environmental pollution and depletion of mineral resources strongly stimulated the research and development of fly ash utilization. Many international fly ash conferences were held, and the research work became more and more in-depth, and there were also many applications. Great progress. Fly ash has become an eye-catching emerging building material raw material and chemical product raw material in the international market that is rich in resources, low in price, and brings benefits and eliminates harm, and is favored by people. Most of the research work on fly ash has shifted from theoretical research to applied research, especially the research and development and utilization of important resources. The products produced using fly ash are constantly increasing, and the technology is constantly being updated. Compared with the past, the comprehensive utilization of fly ash at home and abroad has undergone major changes, mainly as follows: the guiding ideology of fly ash management has changed from a simple environmental perspective in the past to comprehensive management and resource utilization; the comprehensive utilization of fly ash The utilization methods have evolved from the past applications in roadbed, fill, concrete admixtures, soil modification, etc. to cement raw materials, cement admixture materials, large water conservancy project, pumped concrete, large-volume concrete products, advanced Advanced utilization methods such as fillers. The alumina content of high-aluminum fly ash reaches about 38 to 50%, and the silica content reaches 40 to 45%. If they cannot be utilized, a large amount of alumina resources will be lost. The alumina and silica in fly ash are used as raw materials for making silicon-aluminum alloy to maximize the value of fly ash. After impurity removal by hydrochloric acid leaching, acid-leached fly ash is obtained. After high-temperature roasting to remove residual carbon and hydrogen chloride, the fly ash becomes a qualified raw material for making silicon-aluminum alloys. Fly ash hydrochloric acid leaching impurity removal process Mature, high-temperature roasting of fly ash after acid leaching and impurity removal uses traditional rotary kilns and shaft kilns to remove carbon and dechlorination, which have poor and high costs. Therefore, it is necessary to develop a suspension method for dechlorinating fly ash to produce two products. The roasting device and its use method can well solve the above problems of carbon removal and hydrogen chloride removal.

Contents of the invention

The technical problem to be solved by the present invention is to provide a suspension roasting device and a method of use for dechlorinating fly ash to produce two products in view of the above-mentioned deficiencies in the prior art. The purpose is to use the same set of devices and the same fuel, and only change By adjusting the operation process of the device and adjusting the temperature parameters, two products can be produced. One product is a roasted product that removes carbon residue and hydrogen chloride from fly ash, and the other is a dried fly ash product that removes attached water.

In order to solve the above technical problems, the technical solutions adopted by the present invention are:

On the one hand, the present invention provides a suspension roasting device for dechlorinating fly ash to produce two products, including a feeding system, a roasting system, a cooling system, a flue gas dust removal system and a flue gas dechlorination purification system.

The feeding system includes a silo, an electronic quantitative feeder and a feeder; the electronic quantitative feeder supplies materials in the silo to the feeder;

The roasting system includes dryer, flue gas cut-off valve, air valve 1, first-level cyclone preheater, second-level cyclone preheater, insert valve, main roasting furnace, cyclone separator, retention tank, T11 burner, and T12 combustion The feeder, V08 burner, V19 main burner and pneumatic conveying pump 2; the feeder outlet is connected to the dryer inlet, the dryer outlet is connected to the first-level cyclone preheater inlet; the first-level cyclone preheater outlet The material port is connected to the inlet of the secondary cyclone preheater, and a plug-in valve A is provided on the connected pipe; Slider valve B; the second outlet of the pneumatic conveying pump is connected to the dry fly ash silo; the inlet of the secondary cyclone preheater is connected to the outlet of the cyclone separator, and the outlet of the secondary cyclone preheater is connected to the air inlet of the dryer. , the discharge port of the secondary cyclone preheater is connected with the feed port of the main roasting furnace; the inlet of the cyclone separator is connected with the upper outlet of the main roasting furnace; the outlet of the cyclone separator is connected with the inlet of the secondary cyclone preheater; the outlet of the cyclone separator The feed port is connected with the feed port of the retention tank; the air inlet of the main roasting furnace is connected with the air outlet of the primary cyclone cooler; the flue gas pipe connecting the air inlet of the dryer with the air outlet of the secondary cyclone sub-preheater is installed with a smoke pipe. Gas cut-off valve, air valve one and T11 burner; the flue gas cut-off valve is close to the side of the secondary cyclone preheater, and both ends of the flue gas cut-off valve are connected to the flue gas pipeline; the T11 burner is close to the air inlet of the dryer On the other side, the T11 burner is connected to the flue gas pipe; the air valve is located between the flue gas cut-off valve and the T11 burner, with one end connected to the flue gas pipe and the other end connected to the atmosphere; the T12 burner is connected to the inlet pipe of the first-level cyclone cooler Connection; V08 burner and V19 main burner are respectively connected to the air inlet at the bottom of the main roasting furnace through pipes;

The V08 burner serves as an auxiliary burner to ensure safe combustion of the V19 main burner. The V19 main burner provides the main heat for the suspended roasting device. The T11 burner provides heat when producing dry fly ash alone. The T12 burner is a cold furnace. Provide heat when starting the oven and baking it for the first time;

The cooling system includes a first-level cyclone cooler, a second-level cyclone cooler, a third-level cyclone cooler, a final cooler, and a pneumatic conveying pump; the discharge port of the retention tank is connected to the inlet of the first-level cyclone cooler; the inlet of the first-level cyclone cooler It is connected with the air outlet of the second-level cyclone cooler, and the outlet of the first-level cyclone cooler is connected with the air outlet of the third-level cyclone cooler; the air inlet of the third-level cyclone cooler is connected with the atmosphere, and the air outlet of the third-level cyclone cooler is connected with the air outlet of the second-level cyclone cooler. The inlet of the cyclone cooler is connected, the outlet of the three-stage cyclone cooler is connected with the inlet of the final cooler; the outlet of the final cooler is connected with the pneumatic conveying pump, and the outlet of the pneumatic conveying pump is connected with the fly ash product bin ;

The flue gas dust removal system includes a dust collector, an ash return conveyor, an ash bin, and an ash return impeller;

The flue gas dechlorination purification system includes a water washing tower, a neutralization tower, a leaf valve, an exhaust fan, and a chimney;

The air outlet of the first-level cyclone preheater is connected to the inlet of the dust collector, the exhaust outlet of the dust collector is connected to the air inlet of the water washing tower, the air outlet of the water washing tower is connected to the air inlet of the neutralization tower, and the air outlet of the neutralization tower is connected to the air inlet of the neutralization tower through a leaf valve. The exhaust fan is connected, and the outlet of the exhaust fan is connected with the chimney; the discharge port of the dust collector is connected to the ash return conveyor, the ash bin, and one end of the ash return impeller in turn, and the other end of the ash return impeller is connected to the feed inlet of the dryer.

Further, the electronic quantitative feeder is an electronic belt scale or a spiral scale, and materials are supplied to it from a silo.

Further, the feeder is an impeller feeder or a screw feeder, which is used to reduce the amount of air brought in during feeding.

Further, the dryer is a flash dryer or a drying and dispersing machine.

Further, the cyclone preheater uses one or more stages, and the cyclone cooler uses one or more stages; the cyclone preheater uses different stages according to the different moisture content of the fly ash, and the fly ash at the exit of the retention tank uses different stages. The temperature of the final cooler and the temperature of fly ash at the final cooler inlet require the number of stages of the cyclone cooler to be selected.

Further, the main roasting furnace is a cylinder with a lining material, and the bottom is a frustum.

Further, the retention tank is a fluidized bed, and the fluidizing air uses compressed air.

Further, the final cooler uses air to directly or indirectly cool fly ash, or uses water to indirectly cool fly ash; when the final cooler uses air for direct or indirect cooling, the cooling inlet pipe of the final cooler is provided with an air Valve 2; the cooling outlet of the final cooler is connected to the air inlet of the dryer; when the final cooler uses water for indirect cooling, the cooling inlet pipe of the final cooler is equipped with a water flow regulating valve, and the cooling outlet of the final cooler is connected to the air inlet of the dryer. Circulating water cooling system or steam network connection.

Further, when the final cooler uses air for direct cooling, the final cooler is a bag dust collector or a high-efficiency cyclone separator; when the final cooler uses air for indirect cooling, the final cooler is a vertical tube cooler or a horizontal Cooling cooler; when the final cooler uses water for indirect cooling to generate cooling return water, the final cooler is a vertical tube cooler or a horizontal cooling cooler; when the final cooler uses water for indirect cooling to generate steam, the final cooler The equipment is a vertical waste heat boiler or a horizontal cooling boiler.

Further, the dust collector is a bag dust collector, an electrostatic precipitator or an electric bag dust collector,

Further, the ash return conveyor is a screw conveyor, an air chute or a chain plate conveyor.

Further, the fuel used by each burner is gaseous fuel, solid fuel or liquid fuel.

On the other hand, the present invention also provides a method for using the above-mentioned suspension roasting device to dechlorinate fly ash to produce silicon-aluminum alloy raw materials, which includes the following steps:

Step 1: Open the flue gas cut-off valve to make the air outlet of the second-level cyclone preheater and the air inlet of the dryer in the path state. Open the plug-in valve A to make the outlet of the first-level cyclone preheater and the second-level cyclone preheater. The inlet of the device is connected, open air valve 2, and other moving equipment and valves are stopped and closed;

Step 2: Start the exhaust fan, slightly open the leaf valve, and there will be a slight negative pressure in the main roasting furnace; start the T12 burner, and when the temperature at the top of the main roasting furnace reaches 400°C, start the V08 burner, and then start the V19 main burner; When the temperature at the top of the main roasting furnace reaches 700°C, start the electronic quantitative feeder and feeder. When the temperature in the main roasting furnace is stable, turn off the T12 burner;

Step 3: After weighing and measuring the fly ash containing attached water from the bottom of the silo through the electronic quantitative feeder and feeder, it is sent from the feeder to the dryer and mixed with the secondary The hot flue gas is heat exchanged in the cyclone preheater. The temperature of the fly ash after heat exchange is 140~200°C. The attached water detaches and enters the first-level cyclone preheater with the flue gas. After the gas-solid separation, it is preheated by the first-level cyclone. The discharge port of the furnace enters the secondary cyclone preheater for further preheating and gas-solid separation. The preheated and separated fly ash enters the bottom of the main roasting furnace through the discharge port of the secondary cyclone preheater;

Step 4: The cold air is preheated to 600-800°C through the third-stage cyclone cooler, the second-stage cyclone cooler, and the first-stage cyclone cooler and enters the main roasting furnace. The fly ash in the main roasting furnace is fully mixed with the hot air. , roasted with high-temperature flue gas heated by the V19 main burner in the main roasting furnace. The temperature of the main roasting furnace is controlled between 700 and 1000°C. The residual carbon in the fly ash is burned out in the main roasting furnace. Fixed water and hydrogen chloride are removed;

Step 5: In the main roasting furnace, fly ash is roasted by high-temperature flue gas and rises along the furnace to the top of the furnace with the high-temperature flue gas and then enters the cyclone separator;

Step 6: The fly ash separated from gas and solid in the cyclone separator enters the retention tank, and the separated high-temperature flue gas enters the secondary cyclone preheater;

Step 7: The fly ash is further dechlorinated in the retention tank to completely remove the hydrogen chloride in the fly ash. The dechlorinated fly ash is passed through the first-level cyclone cooler, the second-level cyclone cooler, and the third-level cyclone cooler. Cold feed into final cooler;

Step 8: The fly ash is finally cooled in the final cooler. The air enters the final cooler through air valve 2 to exchange heat with the fly ash. The fly ash is cooled to below 80°C and is sent into the pulverized coal through the pneumatic transfer pump. After heat exchange, the hot air returns to the dryer for heat recovery.

Step 9: The flue gas discharged from the first-level cyclone preheater enters the dust collector for dust collection. The dust content of the dust-cleaned flue gas reaches the standard and is sent to the water washing tower. The pulverized coal dust recovered by the dust collector is sent to the ash bin through the ash return conveyor. , evenly sent into the dryer by the return ash impeller.

Step 10: In the water washing tower, the hydrogen chloride gas in the flue gas is greatly absorbed by the water. The washed flue gas then enters the neutralization tower and is neutralized by the sodium hydroxide alkali solution. The purified flue gas is sent into the chimney through the exhaust fan. , and finally discharged into the atmosphere.

Furthermore, in the above steps, the load of the suspended roasting device is achieved by increasing the opening of the leaf valve, increasing the heat load of the V19 main burner, and increasing the feeding amount of the electronic quantitative feeder. By observing the roasting main Furnace top temperature and dust collector outlet flue gas temperature are used to match the three factors.

Further, in the step 3, the fly ash in the silo is the fly ash after acid leaching to remove impurities; the proportion of attached water in the fly ash is 3% to 80%.

Further, in the steps 4 and 7, the total removal rate of hydrogen chloride in fly ash is 99.5%. The dechlorination rate is achieved by controlling the roasting temperature of fly ash in the main roasting furnace and controlling the amount of fly ash in the retention tank. residence time is achieved.

Further, in step 8, the final cooler uses air to directly or indirectly cool the fly ash, or uses water to indirectly cool the fly ash.

When the final cooler uses air for direct or indirect cooling, the air enters the final cooler through air valve 2 to exchange heat with fly ash. The flow of air entering the final cooler is controlled by adjusting the opening of air valve 2. After heat exchange, The hot air returns to the dryer through the cooling outlet of the final cooler for heat recovery.

When the final cooler is indirectly cooled by water, the amount of cooling water entering the final cooler is controlled by adjusting the opening of the water flow regulating valve, thereby controlling the final cooling temperature of the fly ash; after cooling, cooling water or steam is generated and sent into the final cooler. Circulating water cooling system or steam network.

Further, in step 10, the water washing tower uses high-strength atomized water to wash the flue gas and absorb more than 90% of the hydrogen chloride in the flue gas, and the neutralization tower uses sodium hydroxide alkali solution to neutralize the remaining hydrogen chloride in the flue gas. Remove.

Furthermore, in steps 9 and 10, the dust content of the flue gas at the outlet of the dust collector and the HCL content of the flue gas at the outlet of the neutralization tower all meet national environmental protection requirements.

The present invention also provides a first method for producing dry fly ash using the above-mentioned suspension roasting device, which includes the following steps:

Step 11: Open the flue gas cut-off valve, so that the outlet of the second-level cyclone preheater and the air inlet of the dryer are in a passage state; open the plug-in valve B, so that the outlet of the first-level cyclone preheater is connected to the second pneumatic conveying pump; others All moving equipment and valves are stopped and closed;

Step 12: Start the exhaust fan, slightly open the leaf valve, and there is a slight negative pressure in the main roasting furnace. Start the T12 burner. When the temperature at the top of the main roasting furnace reaches 300°C, start the V08 burner, and then start the V19 main burner; When the dryer inlet temperature reaches 250~350℃, start the electronic quantitative feeder and feeder;

Step 13: After the fly ash containing attached water is weighed from the bottom of the silo by the electronic quantitative feeder, it is sent from the feeder to the dryer, where it heat exchanges with the hot flue gas from the secondary cyclone preheater. The temperature of the fly ash after heat exchange is 140~200℃. The attached water detaches and enters the first-level cyclone preheater with the flue gas. The fly ash after gas-solid separation passes through the discharge port and inserting plate of the first-level cyclone preheater. Valve B enters the pneumatic conveying pump 2, and then is sent to the dry fly ash silo;

Step 14: The cold air enters the first-level cyclone cooler through the third-level cyclone cooler and the second-level cyclone cooler, is heated by the T12 burner, and enters the air inlet at the bottom of the main roasting furnace through the first-level cyclone cooler; the heated hot air is After the main roasting furnace is further heated by the V19 main burner, it enters the dryer through the cyclone separator and the secondary cyclone preheater;

Step 15: The dried fly ash in the dryer is brought into the first-level cyclone preheater by the hot flue gas for gas-solid separation. The flue gas discharged from the first-level cyclone preheater enters the dust collector for dust collection. The recovered dust is returned to the dryer. The ash conveyor sends the ash into the silo and is evenly sent into the dryer through the ash return impeller;

Step 16: The hot flue gas after dust removal by the dust collector enters the water washing tower. The hydrogen chloride gas in the flue gas is greatly absorbed by the water. The washed flue gas then enters the neutralization tower and is neutralized by the sodium hydroxide alkali solution. The purified flue gas The air is sent into the chimney through the exhaust fan and finally discharged into the atmosphere.

Further, in the above steps, the ability of the device to dry fly ash is achieved by increasing the opening of the leaf valve, increasing the heat load of the V19 main burner, and increasing the feeding amount of the electronic quantitative feeder; by controlling a The outlet temperature of the cyclone preheater is used to control the drying quality of fly ash.

Further, in the step 13, the fly ash in the silo is the fly ash after acid leaching to remove impurities; the proportion of attached water in the fly ash is 3% to 80%.

Further, in step 16, the water washing tower uses high-strength atomized water to wash the flue gas to absorb more than 90% of the hydrogen chloride in the flue gas, and the neutralization tower uses sodium hydroxide alkali solution to neutralize the remaining hydrogen chloride in the flue gas. and removal.

Furthermore, in steps 15 and 16, the dust content of the flue gas at the outlet of the dust collector and the HCL content of the flue gas at the outlet of the neutralization tower all meet national environmental protection requirements.

The present invention also provides a second method for producing dry fly ash using the above-mentioned suspension roasting device, which includes the following steps:

Step 21: Open the air valve 1, close the flue gas cut-off valve, so that the atmosphere and the dryer are in the communication state, open the gate valve B, and other moving equipment and valves are stopped and closed;

Step 22: Start the exhaust fan, open the 20% leaf valve, and start the T11 burner;

Step 23: Start the electronic quantitative feeder and feeder, weigh and measure the fly ash containing attached water from the bottom of the silo through the electronic quantitative feeder, and then send it from the feeder to the dryer; from the air valve The incoming air mixes with the high-temperature flue gas generated by the T11 burner and then enters the dryer. The wet fly ash is dried by the hot flue gas; the temperature of the fly ash after heat exchange is 140~200°C, and the attached water is detached here. After drying After the gas-solid separation in the first-level cyclone preheater, the fly ash enters the pneumatic conveying pump 2 through the plug-in valve B, and is sent to the dry fly ash silo by the pneumatic conveying pump 2;

Step 24: The flue gas after gas-solid separation in the first-level cyclone preheater is discharged from the outlet of the first-level cyclone preheater and sent to the dust collector. The flue gas after dust removal contains a small amount of hydrogen chloride and enters the water washing tower. The hydrogen chloride gas in the flue gas Absorbed by water, the washed flue gas then enters the neutralization tower and is neutralized by sodium hydroxide alkali solution. The purified flue gas is sent to the chimney through the exhaust fan and discharged into the atmosphere.

Step 25: The dust recovered by the dust collector is sent to the ash bin through the ash return conveyor, and evenly sent into the dryer through the ash return impeller.

Further, in the step 23, the fly ash in the silo is the fly ash after impurity removal by acid leaching; the proportion of attached water in the fly ash is 3% to 80%.

Further, in step 24, the water washing tower uses high-intensity atomized water to wash the flue gas to absorb more than 90% of the hydrogen chloride in the flue gas, and the neutralization tower uses sodium hydroxide alkali solution to neutralize the remaining hydrogen chloride in the flue gas. and removal; the dust content in the flue gas at the outlet of the dust collector and the HCL content in the flue gas at the outlet of the neutralization tower all meet national environmental protection requirements.

The beneficial effects of adopting the above technical solution are that the suspension roasting device for dechlorinating fly ash and producing two products provided by the present invention has a compact structure, high single unit production capacity, high degree of automation, high operating rate, and greatly reduced labor intensity. Using a set of equipment and using the same raw material, by adjusting the process operation flow and process operation parameters, two products, namely fly ash roasting products and fly ash drying products, can be produced. The invention has large production capacity, simple process, easy operation, low production cost and high carbon and hydrogen chloride removal rate. The method of the present invention uses fluidization technology to perform cascade utilization and recovery of high-temperature flue gas and material waste heat. During the carbon removal process, the heat released by burning char saves combustion consumption.

Description of the drawings

Figure 1 is a schematic structural diagram of a suspension roasting device for producing two products by dechlorinating fly ash according to an embodiment of the present invention;

Figure 2 is a schematic diagram of cooling water generated when the final cooler provided by the embodiment of the present invention uses water for indirect cooling;

Figure 3 is a schematic diagram of steam generated when the final cooler is indirectly cooled by water according to an embodiment of the present invention.

In the picture: 1. Silo; 2. Electronic quantitative feeder; 3. Dryer; 4. Flue gas cut-off valve; 5. Air valve one; 6. Air valve two; 7. First-level cyclone preheater; 7 -1. Slide valve A; 7-2. Slide valve B; 8. Secondary cyclone preheater; 9. Main roasting furnace; 10. Cyclone separator; 11. Retention tank; 12. First-level cyclone cooler ; 13. Two-stage cyclone cooler; 14. Three-stage cyclone cooler; 15. Final cooler; 16. Pneumatic conveying pump 1; 17. Dust collector; 18. Ash return conveyor; 19. Ash bin; 20. Return Ash impeller; 21. T11 burner; 22. T12 burner; 23. V08 burner; 24. V19 main burner; 25. Pneumatic transfer pump 2; 26. Water washing tower; 27. Neutralization tower; 28. Plate blades Valve; 29. Exhaust fan; 30. Chimney.

Detailed ways

Specific implementations of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the invention but are not intended to limit the scope of the invention.

Example 1

As shown in Figure 1, the suspension roasting device for producing two products by dechlorinating fly ash in this embodiment includes a feeding system, a roasting system, a cooling system, a flue gas dust removal system and a flue gas dechlorination purification system.

The feeding system includes silo 1, electronic quantitative feeder 2 and feeder 2-1.

The roasting system includes dryer 3, flue gas cut-off valve 4, air valve 1-5, first-level cyclone preheater 7, second-level cyclone preheater 8, gate valve A 7-1, gate valve B 7-2, Roasting main furnace 9, cyclone separator 10, retention tank 11, T11 burner 21, T12 burner 22, V08 burner 23, V19 main burner 24 and pneumatic transfer pump 22.

The cooling system includes a first-stage cyclone cooler 12, a second-stage cyclone cooler 13, a third-stage cyclone cooler 14, a final cooler 15, a pneumatic transfer pump 16, and an air valve 26.

The flue gas dust removal system includes a dust collector 17, an ash return conveyor 18, an ash bin 19, and an ash return impeller 20.

The flue gas dechlorination purification system includes a water washing tower 26, a neutralization tower 27, a leaf valve 28, an exhaust fan 29, and a chimney 30.

The electronic quantitative feeder 2 supplies materials in the bin 1 to the feeder 2-1. In this embodiment, the electronic quantitative feeder 2 is an electronic belt scale. The feeder 2-1 is an impeller feeder, used to reduce the amount of air brought in during feeding.

The outlet of the feeder 2-1 is connected with the inlet of the dryer 3, and the outlet of the dryer 3 is connected with the inlet of the first-level cyclone preheater 7; the outlet of the first-level cyclone preheater 7 is connected with the second-level cyclone preheater. The inlet of heater 8 is connected, and a plug-in valve A7-1 is provided on the connected pipe; the discharge port of the first-level cyclone preheater 7 is connected to the pneumatic conveying pump 225 at the same time, and a plug-in plate is provided on the connected pipe. Valve B7-2; the 25 outlet of the pneumatic conveying pump is connected to the dry fly ash silo. The inlet of the secondary cyclone preheater 8 is connected to the air outlet of the cyclone separator 10 at the same time. The outlet of the secondary cyclone preheater 8 is connected to the air inlet of the dryer 3. The outlet of the secondary cyclone preheater 8 is connected to the main roasting furnace. 9 feed port is connected; the cyclone separator 10 inlet is connected with the upper outlet of the roasting main furnace 9, the cyclone separator 10 outlet is connected with the secondary cyclone preheater 8 inlet, the cyclone separator 10 outlet is connected with the retention tank 11 feed Mouth connected. The air inlet of the roasting main furnace 9 is connected with the air outlet of the first-level cyclone cooler 12. The flue gas pipe connecting the air inlet of the dryer 3 and the air outlet of the secondary cyclone preheater 8 is equipped with a flue gas cut-off valve 4, an air valve 1 5 and a T11 burner 21; the flue gas cut-off valve 4 is close to the secondary cyclone One side of the preheater 8, and both ends of the flue gas cut-off valve 4 are connected to the flue gas pipe; the T11 burner 21 is close to the air inlet side of the dryer 3, and the T11 burner 21 is connected to the flue gas pipe; air valve 15 Located between the flue gas cut-off valve 4 and the T11 burner 21, one end is connected to the flue gas pipe and the other end is connected to the atmosphere; the T12 burner 21 is connected to the inlet pipe of the primary cyclone cooler 12; the V08 burner 23 and the V19 main combustion The devices 24 are respectively connected with the air inlet at the bottom of the roasting main furnace 9 through pipes.

During the use of the device, the cyclone preheater uses one or more stages as needed. Depending on the moisture content of fly ash, different stages are selected for the cyclone preheater.

The V08 burner serves as an auxiliary burner to ensure safe combustion of the V19 main burner. The V19 main burner provides the main heat for the suspended roasting device. The T11 burner provides heat when producing dry fly ash alone. The T12 burner is a cold furnace. Provide heat when starting the oven and baking it for the first time.

In this embodiment, the dryer 3 adopts a flash dryer. The main roasting furnace 9 is a cylinder with a lining material, and the bottom is a frustum. The retention tank 11 adopts a fluidized bed, and the fluidizing air adopts compressed air.

The outlet of the residence tank 11 is connected with the inlet of the first-level cyclone cooler 12; the inlet of the first-level cyclone cooler 12 is connected with the outlet of the second-level cyclone cooler 13, and the outlet of the first-level cyclone cooler 12 is connected with the third-level cyclone cooler 14. The air outlet is connected. The air inlet of the three-stage cyclone cooler 14 is connected with the atmosphere, the air outlet of the three-stage cyclone cooler 14 is connected with the inlet of the two-stage cyclone cooler 13, and the discharge port of the three-stage cyclone cooler 14 is connected with the feed port of the final cooler 15. The outlet of the final cooler 15 is connected to the pneumatic conveying pump 16, and the outlet of the pneumatic conveying pump 16 is connected to the fly ash product bin. The cold air introduced into the air inlet of the three-stage cyclone cooler 14 is preheated by the two-stage cyclone cooler 13 and the first-stage cyclone cooler 12 and then enters the main roasting furnace 9 . The cooling inlet pipe of the final cooler 15 is provided with an air valve 26. In this embodiment, the final cooler 15 uses air to directly cool fly ash and uses a bag dust collector. The cooling outlet of the final cooler 15 is connected with the air inlet of the dryer 3 . The air inlet is connected to the final cooler 15 through the air valve 26, and the heat-exchanged hot air returns to the dryer 3 through the cooling outlet of the final cooler 15 for use.

During the use of the device, the cyclone cooler uses one or more stages as needed. The number of stages of the cyclone cooler is selected according to the temperature requirements of the fly ash at the exit of the retention tank and the fly ash at the inlet of the final cooler.

The air outlet of the first-level cyclone preheater 7 is connected with the inlet of the dust collector 17, the exhaust outlet of the dust collector 17 is connected with the air inlet of the water washing tower 26, the air outlet of the water washing tower 26 is connected with the air inlet of the neutralization tower 27, and the neutralization tower 27 The air outlet is connected to the exhaust fan 29 through the leaf valve 28, and the outlet of the exhaust fan 29 is connected to the chimney 30. The discharge port of the dust collector 17 is connected in sequence to the ash return conveyor 18, the ash bin 19, and one end of the ash return impeller 20. The other end of the ash return impeller 20 is connected to the feed port of the dryer 3.

In this embodiment, the dust collector 17 adopts a bag dust collector, the ash return conveyor 18 adopts a screw conveyor, and the fuel used by each burner is gaseous fuel.

Example 2

The differences between this embodiment and Embodiment 1 include:

The electronic quantitative feeder 2 is a spiral scale, the feeder 2-1 is a spiral feeder, the dryer 3 adopts a drying and dispersing machine, and the final cooler 15 adopts a high-efficiency cyclone separator. The dust collector 17 adopts an electrostatic precipitator, the ash return conveyor 18 adopts an air chute, and the fuel used by each burner is solid fuel.

Other structures are the same as in Embodiment 1.

Example 3

The differences between this embodiment and Embodiment 1 include:

The final cooler 15 uses air to indirectly cool fly ash and adopts a vertical tube cooler; the dust collector 17 uses an electric bag dust collector, and the ash return conveyor 18 uses a chain plate conveyor.

The fuel used by each of the burners is liquid fuel.

Other structures are the same as in Embodiment 1.

Example 4

The differences between this embodiment and Embodiment 3 include:

The final cooler 15 adopts a horizontal cooling cooler.

Other structures are the same as those in Embodiment 3.

Example 5

The differences between this embodiment and Embodiment 1 include:

The final cooler 15 uses water for indirect cooling and generates cooling water. The cooling outlet of the final cooler 15 is connected to the circulating water cooling system, and the generated cooling water is sent to the circulating water cooling system, as shown in Figure 2. At this time, the cooling inlet of the final cooler 15 is provided with a water flow regulating valve for controlling the amount of cooling water entering the final cooler.

The final cooler 15 adopts a vertical tube cooler.

Other structures are the same as in Embodiment 1.

Example 6

The differences between this embodiment and Embodiment 5 include:

The final cooler 15 adopts a horizontal cooling cooler.

Other structures are the same as those in Embodiment 5.

Example 7

The differences between this embodiment and Embodiment 1 include:

The final cooler 15 uses water for indirect cooling and generates steam. The cooling outlet of the final cooler 15 is connected to the steam network, and the generated steam is sent to the steam network, as shown in Figure 3. At this time, the cooling inlet of the final cooler 15 is provided with a water flow regulating valve for controlling the amount of cooling water entering the final cooler.

The final cooler 15 adopts a vertical waste heat boiler.

Other structures are the same as those in Embodiment 1.

Example 8

The differences between this embodiment and Embodiment 7 include:

The final cooler 15 adopts a horizontal cooling boiler.

Other structures are the same as those in Embodiment 7.

Example 9

This embodiment provides a method for using the suspension roasting device of Embodiment 1 or 2 to dechlorinate fly ash to produce silicon-aluminum alloy raw materials, including the following steps:

Step 1: Open the flue gas cut-off valve 4, so that the air outlet of the second-level cyclone preheater 8 and the air inlet of the dryer 3 are in the passage state, open the gate valve A7-1, and make the outlet of the first-level cyclone preheater 7 It is connected with the inlet of the secondary cyclone preheater 8, opens the air valve 26, and other moving equipment and valves are stopped and closed;

Step 2: Start the exhaust fan 29, slightly open the leaf valve 28, and there is a slight negative pressure in the main roasting furnace 9; start the T12 burner 22, and when the top temperature of the main roasting furnace 9 reaches 400°C, start the V08 burner 23, Restart the V19 main burner 24; when the temperature at the top of the main roasting furnace 9 reaches 700°C, start the electronic quantitative feeder 2 and the feeder 2-1; when the temperature in the furnace of the main roasting furnace 9 is stable, close the T12 burner 22;

Step 3: Use the electronic quantitative feeder 2 and the feeder 2-1 to weigh and measure the fly ash containing 3 to 80% attached water from the bottom of the silo 1 through the electronic quantitative feeder 2, and then use the feeder to 2-1 is sent to the dryer 3, and is heat exchanged with the hot flue gas from the secondary cyclone preheater 8. The temperature of the fly ash after heat exchange is 140~200°C, and the attached water detaches and enters the first level with the flue gas. Cyclone preheater 7. After gas-solid separation, the discharge port of the first-level cyclone preheater 7 enters the second-level cyclone preheater 8 for further preheating and gas-solid separation. The preheated and separated fly ash is preheated by the second-level cyclone preheater 7. The outlet of the heater 8 enters the bottom of the main roasting furnace 9;

Step 4: The cold air is preheated to 600-800°C through the third-stage cyclone cooler 14, the second-stage cyclone cooler 13, and the first-stage cyclone cooler 12 and enters the main roasting furnace 9. The fly ash in the main roasting furnace 9 is mixed with The hot air is fully mixed, and is roasted by the high-temperature flue gas heated by the V19 main burner 24 in the main roasting furnace 9. The temperature of the main roasting furnace is controlled at 700-1000°C. The residual carbon in the fly ash is burned in the main roasting furnace 9. After burning, the fixed water and hydrogen chloride in the fly ash are removed;

Step 5: In the main roasting furnace 9, the fly ash is roasted by the high-temperature flue gas and rises along the furnace to the top of the furnace with the high-temperature flue gas and then enters the cyclone separator 10;

Step 6: The fly ash separated from gas and solid in the cyclone separator 10 enters the retention tank 11, and the separated high-temperature flue gas enters the secondary cyclone preheater 8;

Step 7: The fly ash is further dechlorinated in the retention tank 11 to completely remove the hydrogen chloride in the fly ash. The dechlorinated fly ash is passed through the first-level cyclone cooler 12, the second-level cyclone cooler 13, and the third-level cyclone cooler. The cold 14 from the cyclone cooler is sent to the final cooler;

Step 8: The fly ash is finally cooled in the final cooler 15. The fly ash is cooled to below 80°C and sent to the fly ash product bin through the pneumatic conveying pump 16;

Step 9: The flue gas discharged from the first-level cyclone preheater 7 enters the dust collector 17 for dust collection. The dust content of the dust-cleaned flue gas reaches the standard and is sent to the water washing tower 26. The pulverized coal dust recovered by the dust collector 17 passes through the return ash conveyor. 18 is sent into the ash bin 19, and is evenly sent into the dryer 3 by the return ash impeller 20;

Step 10: In the water washing tower 26, the hydrogen chloride gas in the flue gas is greatly absorbed by the water. The washed flue gas then enters the neutralization tower 27 and is neutralized by the sodium hydroxide alkali solution. The purified flue gas passes through the exhaust fan 29 It is sent into the chimney 30 and finally discharged into the atmosphere.

In the above steps, the load of the suspended roasting device is achieved by increasing the opening of the leaf valve 29, increasing the heat load of the V19 main burner 24, and increasing the feeding amount of the electronic quantitative feeder 2. By observing the roasting main The top temperature of the furnace 9 and the flue gas temperature at the outlet of the dust collector 17 are used to achieve matching of the three factors.

In step 3, the fly ash in the silo 1 is the fly ash after impurity removal by acid leaching.

In step 4, the residual carbon in the fly ash is burned out in the main roasting furnace 9, and the heat released can reduce the amount of fuel consumed by the V19 main burner 24.

In the steps 4 and 7, the total removal rate of hydrogen chloride in fly ash is 99.5%. The dechlorination rate is achieved by controlling the roasting temperature of fly ash in the main roasting furnace 9 and controlling the concentration of fly ash in the retention tank 11. Dwell time achieved.

In step 8, the final cooler 15 uses air to directly cool the fly ash. The air enters the final cooler 15 through the air valve 26 to exchange heat with the fly ash. The air enters the final cooling by adjusting the opening of the air valve 26. The flow rate of the air in the device 15 is controlled, and the heat-exchanged hot air returns to the dryer 3 through the cooling outlet of the final cooler 15 for heat recovery.

In step 10, the water washing tower 26 uses high-intensity atomized water to wash the flue gas and absorb more than 90% of the hydrogen chloride in the flue gas. The neutralization tower 26 uses sodium hydroxide alkali solution to neutralize and remove the remaining hydrogen chloride in the flue gas. remove.

In the steps 9 and 10, the dust content of the flue gas at the outlet of the dust collector 17 and the HCL content of the flue gas at the outlet of the neutralization tower 27 all meet the national environmental protection requirements.

Example 10

This embodiment is a method of using the suspension roasting device of Embodiment 3 or 4 to dechlorinate fly ash to produce silicon-aluminum alloy raw materials. The differences between this embodiment and Embodiment 9 include:

In step 8, the final cooler 15 uses air to indirectly cool the fly ash.

Other procedures are the same as those in Example 9.

Example 11

This embodiment is a method of using the suspension roasting device of Embodiment 5 or 6 to dechlorinate fly ash to produce silicon-aluminum alloy raw materials. The differences between this embodiment and Embodiment 9 include:

In step 8, the final cooler 15 uses water to indirectly cool the fly ash. By adjusting the opening of the water flow control valve, the amount of cooling water entering the final cooler 15 is controlled, thereby controlling the final cooling temperature of the fly ash. . The cooling water generated by the final cooler 15 is sent to the circulating water cooling system through the cooling outlet of the final cooler 15 .

Other procedures are the same as those in Example 9.

Example 12

This embodiment is a method of using the suspension roasting device of Embodiment 7 or 8 to dechlorinate fly ash to produce silicon-aluminum alloy raw materials. The differences between this embodiment and Embodiment 11 include:

In step 8, the final cooler 15 uses water to indirectly cool the fly ash. By adjusting the opening of the water flow control valve, the amount of cooling water entering the final cooler 15 is controlled, thereby controlling the final cooling temperature of the fly ash. . After being cooled by the final cooler 15, the steam generated is sent to the steam network through the cooling outlet of the final cooler 15.

Other procedures are the same as those in Example 11.

Example 13

This embodiment provides a first method for producing dry fly ash using the suspension roasting device of Embodiment 1, which includes the following steps:

Step 11: Open the flue gas cut-off valve 4, so that the outlet of the second-level cyclone preheater 8 and the air inlet of the dryer 3 are in a passage state; open the plug-in valve B 7-2, so that the outlet of the first-level cyclone preheater 7 is connected with the air inlet of the dryer 3. The pneumatic conveying pump 2 and 25 are connected; other moving equipment and valves are stopped and closed;

Step 12: Start the exhaust fan 29, slightly open the leaf valve 28, there is a slight negative pressure in the main roasting furnace 9, start the T12 burner 22, when the top temperature of the main roasting furnace 9 reaches 300°C, start the V08 burner 23, Restart V19 main burner 24; when the inlet temperature of dryer 3 reaches 250~350°C, start electronic quantitative feeder 2 and feeder 2-1;

Step 13: After the fly ash containing 3 to 80% attached water is weighed and measured from the bottom of the silo 1 by the electronic quantitative feeder 2, it is sent to the dryer 3 from the feeder 2-1 and mixed with the secondary cyclone. The hot flue gas is heat exchanged in the preheater 8. The temperature of the fly ash after the heat exchange is 140-200°C. The attached water detaches and enters the first-level cyclone preheater 7 with the flue gas. The fly ash after gas-solid separation passes through The discharge port of the first-level cyclone preheater 7 and the gate valve B 7-2 enter the pneumatic conveying pump 225, and then are sent to the dry fly ash silo;

Step 14: The cold air enters the first-level cyclone cooler 12 through the third-level cyclone cooler 14 and the second-level cyclone cooler 13, is heated by the T12 burner 22, and enters the bottom air inlet of the roasting main furnace 9 through the first-level cyclone cooler 12; The heated hot air is further heated by the V19 main burner 24 in the main roasting furnace 9, and then enters the dryer 3 through the cyclone separator 10 and the secondary cyclone preheater 8;

Step 15: The dried fly ash in the dryer 3 is brought into the first-level cyclone preheater 7 by the hot flue gas for gas-solid separation. The flue gas discharged from the first-level cyclone preheater 7 enters the dust collector 17 for dust collection and recycling. The dust is sent to the ash bin 19 through the ash return conveyor 18, and evenly sent into the dryer 3 through the ash return impeller 20;

Step 16: The hot flue gas after dust removal by the dust collector 17 enters the water washing tower 26. The hydrogen chloride gas in the flue gas is greatly absorbed by the water. The washed flue gas then enters the neutralization tower 27 and is neutralized by the sodium hydroxide alkali solution. The purified flue gas is sent into the chimney 30 through the exhaust fan 29, and finally discharged into the atmosphere.

In the above steps, the ability of the device to dry fly ash is achieved by increasing the opening of the leaf valve 28, increasing the heat load of the V19 main burner 23, and increasing the feeding amount of the electronic quantitative feeder 2; by controlling a The outlet temperature of the 7-stage cyclone preheater is used to control the drying quality of fly ash.

In step 13, the fly ash in the silo 1 is the fly ash after acid leaching to remove impurities.

In step 16, the water washing tower 26 uses high-strength atomized water to wash the flue gas and absorb more than 90% of the hydrogen chloride in the flue gas. The neutralization tower 27 uses sodium hydroxide alkali solution to neutralize the remaining hydrogen chloride in the flue gas. Remove.

In the steps 15 and 16, the dust content of the flue gas at the outlet of the dust collector 17 and the HCL content of the flue gas at the outlet of the neutralization tower 27 all meet the national environmental protection requirements.

Example 14

This embodiment provides a second method for producing dry fly ash using the suspension roasting device of Embodiment 1, which includes the following steps:

Step 21: Open the air valve 15, close the flue gas cut-off valve 4, so that the atmosphere and the dryer 3 are connected, open the gate valve B7-2, and other moving equipment and valves are stopped and closed;

Step 22: Start the exhaust fan 29, open the 20% leaf valve 28, and start the T11 burner 21;

Step 23: Start the electronic quantitative feeder 2 and the feeder 2-1, and weigh the fly ash containing attached water from the bottom of the silo 1 through the electronic quantitative feeder 2, and then through the feeder 2-1 It is sent to the dryer 3; the air entering from the air valve 5 is mixed with the high-temperature flue gas generated by the T11 burner 21 and then enters the dryer 3. The wet fly ash is dried by the hot flue gas; the temperature of the fly ash after heat exchange is 140~200℃, the attached water is separated here, and the dried fly ash enters the pneumatic conveying pump 225 through the gate valve B7-2 after gas-solid separation in the first-stage cyclone preheater 7, and is sent by the pneumatic conveying pump 225 into dry fly ash silo;

Step 24: The flue gas after gas-solid separation in the first-level cyclone preheater 7 is discharged from the outlet of the first-level cyclone preheater 7 and sent to the dust collector 17. The dust-removed flue gas contains a small amount of hydrogen chloride and enters the water washing tower 26. The flue gas The hydrogen chloride gas in the flue gas is absorbed by water, and the washed flue gas then enters the neutralization tower 27 and is neutralized by sodium hydroxide alkali solution. The purified flue gas is sent to the chimney 30 through the exhaust fan 29 and discharged into the atmosphere;

Step 25: The dust recovered by the dust collector 17 is sent to the ash bin 19 through the ash return conveyor 18, and is evenly sent into the dryer 3 through the ash return impeller 20.

In the step 23, the fly ash in the silo 1 is the fly ash after acid leaching to remove impurities; the proportion of attached water in the fly ash is 3% to 80%.

In the step 24, the water washing tower 26 uses high-strength atomized water to wash the flue gas and absorb more than 90% of the hydrogen chloride in the flue gas. The neutralization tower 27 uses sodium hydroxide alkali solution to neutralize the remaining hydrogen chloride in the flue gas. Removal; The dust content of the flue gas at the outlet of dust collector 17 and the HCL content of the flue gas at the outlet of neutralization tower 27 all meet the national environmental protection requirements.

The suspension roasting device for dechlorinating fly ash to produce two products has a compact structure, high single unit production capacity, high degree of automation, high operating rate, and greatly reduced labor intensity. Using a set of equipment and using the same raw material, by adjusting the process operation flow and process operation parameters, two products, namely fly ash roasting products and fly ash drying products, can be produced. The invention has large production capacity, simple process, easy operation, low production cost and high carbon and hydrogen chloride removal rate. The method of the present invention uses fluidization technology to perform cascade utilization and recovery of high-temperature flue gas and material waste heat. During the carbon removal process, the heat released by burning char saves combustion consumption.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, but not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the claims of the present invention. .

Claims (27)

1. A suspension roasting device for producing two products by dechlorinating fly ash, which is characterized by: including a feeding system, a roasting system, a cooling system, a flue gas dust removal system and a flue gas dechlorination purification system; The feeding system includes a silo (1), an electronic quantitative feeder (2) and a feeder (2-1); The roasting system includes a dryer (3), a flue gas cut-off valve (4), an air valve (5), a cyclone preheater, a sliding plate valve, a main roasting furnace (9), a cyclone separator (10), and a retention tank ( 11), T11 burner (21), T12 burner (22), V08 burner (23), V19 main burner (24) and pneumatic transfer pump two (25); the cyclone preheater includes one-stage cyclone preheating (7), two-stage cyclone preheater (8); The cooling system includes a cyclone cooler, a final cooler (15), and a pneumatic transfer pump (16); the cyclone cooler includes a first-level cyclone cooler (12), a second-level cyclone cooler (13), and a third-level cyclone cooler (13). 14); The flue gas dust removal system includes a dust collector (17), an ash return conveyor (18), an ash bin (19), and an ash return impeller (20); The flue gas dechlorination purification system includes a water washing tower (26), a neutralization tower (27), a leaf valve (28), an exhaust fan (29), and a chimney (30); The electronic quantitative feeder (2) supplies the materials in the silo (1) to the feeder (2-1); The outlet of the feeder (2-1) is connected to the inlet of the dryer (3), and the outlet of the dryer (3) is connected to the inlet of the first-level cyclone preheater (7); the first-level cyclone preheater (7) The discharge port is connected to the inlet of the secondary cyclone preheater (8), and a plug valve A (7-1) is provided on the connected pipe; the discharge port of the primary cyclone preheater (7) is connected to the pneumatic conveyor at the same time. The second pump (25) is connected, and a plug valve B (7-2) is provided on the connected pipeline; the outlet of the second pneumatic conveying pump (25) is connected to the dry fly ash silo; the secondary cyclone preheater (8 ) inlet is connected to the air outlet of the cyclone separator (10), the air outlet of the secondary cyclone preheater (8) is connected to the air inlet of the dryer (3), and the outlet of the secondary cyclone preheater (8) is connected to the roasting port. The feed port of the main furnace (9) is connected; the inlet of the cyclone separator (10) is connected with the upper outlet of the roasting main furnace (9), and the outlet of the cyclone separator (10) is connected with the inlet of the secondary cyclone preheater (8). The discharge port of the separator (10) is connected to the feed port of the retention tank (11); the air inlet of the roasting main furnace (9) is connected to the air outlet of the first-level cyclone cooler (12); the air inlet of the dryer (3) is connected to the air inlet of the main roasting furnace (9). The flue gas pipe connected to the outlet of the secondary cyclone sub-preheater is equipped with a flue gas cut-off valve (4), air valve one (5) and T11 burner (21); the flue gas cut-off valve (4) is close to the secondary cyclone On the side of the preheater (8), and both ends of the flue gas cut-off valve (4) are connected to the flue gas pipe; on the side of the T11 burner (21) close to the air inlet of the dryer (3), the T11 burner (21) Connected to the flue gas pipe; air valve one (5) is located between the flue gas cut-off valve (4) and the T11 burner (21), with one end connected to the flue gas pipe and the other end connected to the atmosphere; the T12 burner (22) is connected to the flue gas pipe. The inlet pipe of the first-level cyclone cooler (12) is connected; the V08 burner (23) and the V19 main burner (24) are respectively connected to the bottom air inlet of the roasting main furnace (9) through pipes; The V08 burner (23) serves as an auxiliary burner to ensure the safe combustion of the V19 main burner (24). The V19 main burner (24) provides the main heat for the suspension roasting device, and the T11 burner (21) is used to separately produce dry powder. The T12 burner (22) provides heat when starting the cold furnace and first drying the furnace; The outlet of the retention tank (11) is connected with the inlet of the first-level cyclone cooler (12); the inlet of the first-level cyclone cooler (12) is connected with the outlet of the second-level cyclone cooler (13), and the first-level cyclone cooler (12) The discharge port is connected with the air outlet of the three-stage cyclone cooler (14); the air inlet of the three-stage cyclone cooler (14) is connected with the atmosphere, and the air outlet of the three-stage cyclone cooler (14) is connected with the secondary cyclone cooler (13) The inlet is connected, and the discharge port of the three-stage cyclone cooler (14) is connected with the feed port of the final cooler (15); the discharge port of the final cooler (15) is connected with the pneumatic conveying pump (16), and the pneumatic conveying pump (16) is connected. 16) The discharge port is connected to the fly ash product bin; The air outlet of the first-level cyclone preheater (7) is connected with the inlet of the dust collector (17), the exhaust outlet of the dust collector (17) is connected with the air inlet of the water washing tower (26), and the air outlet of the water washing tower (26) is connected with the neutralization tower. (27) The air inlet is connected, the air outlet of the neutralization tower (27) is connected with the exhaust fan (29) through the leaf valve (28), the outlet of the exhaust fan (29) is connected with the chimney (30); the dust collector (17) outlet The material port is connected to one end of the ash return conveyor (18), the ash bin (19), and the ash return impeller (20) in sequence. The other end of the ash return impeller (20) is connected to the feed port of the dryer (3). 2. The suspension roasting device for producing two products by dechlorinating fly ash according to claim 1, characterized in that: the electronic quantitative feeder (2) is an electronic belt scale or a spiral scale, and is composed of a silo (1 ) supplies materials to it. 3. The suspension roasting device for producing two products by dechlorinating fly ash according to claim 1, characterized in that: the feeder (2-1) is an impeller feeder or a screw feeder. Reduce the amount of air introduced during feeding. 4. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the dryer (3) is a flash dryer or a drying and dispersing machine. 5. The suspension roasting device for producing two products by dechlorinating fly ash according to claim 1, characterized in that: the cyclone preheater and the cyclone cooler can be removed or increased in number as needed during use. One or more stages; select different cyclone preheater stages according to the different moisture content of the fly ash; according to the temperature of the fly ash at the outlet of the retention tank (11), the imported fly ash of the final cooler (15) The temperature requirements select the number of stages of the cyclone cooler. 6. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the main roasting furnace (9) is a cylinder with a lining material, and the bottom is a frustum. body. 7. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the retention tank (11) is a fluidized bed, and the fluidizing air adopts compressed air. 8. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the final cooler (15) uses air to directly or indirectly cool fly ash, or uses water to cool indirectly. Fly ash; when the final cooler (15) adopts air direct or indirect cooling, the cooling inlet pipe of the final cooler (15) is provided with air valve two (6), and the cooling outlet of the final cooler (15) is connected with the dryer. The air inlet of the machine (3) is connected; when the final cooler (15) uses water for indirect cooling, the cooling inlet pipe of the final cooler (15) is provided with a water flow regulating valve, and the cooling outlet of the final cooler (15) Connected to circulating water cooling system or steam network. 9. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 8, characterized in that: when the final cooler (15) adopts air direct cooling, the final cooler (15) is a bag type Dust collector or high-efficiency cyclone separator; when the final cooler (15) adopts air indirect cooling, the final cooler (15) is a vertical tube cooler or a horizontal refrigeration cooler; the final cooler (15) uses water When indirect cooling produces cooling return water, the final cooler (15) is a vertical tube cooler or a horizontal refrigeration cooler; when the final cooler (15) is indirectly cooled with water to generate steam, the final cooler (15) is Vertical waste heat boiler or horizontal cooling boiler. 10. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the dust collector (17) is a bag dust collector, an electrostatic precipitator or an electric bag dust collector. 11. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the ash return conveyor (18) is a screw conveyor, an air chute or a chain plate conveyor. 12. The suspension roasting device for dechlorinating fly ash to produce two products according to claim 1, characterized in that: the fuel used by each burner is gaseous fuel, solid fuel or liquid fuel. 13. A method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash, characterized in that: the method uses the suspension roasting device of claim 1 for production, and includes the following steps: Step 1: Open the flue gas cut-off valve (4), so that the air outlet of the secondary cyclone preheater (8) and the air inlet of the dryer (3) are in a path state, open the plug-in valve A (7-1), and make a The outlet of the first-level cyclone preheater (7) is connected to the inlet of the second-level cyclone preheater (8), open the second air valve (6), and other moving equipment and valves are stopped and closed; Step 2: Start the exhaust fan (29), slightly open the leaf valve (28), and there will be a slight negative pressure in the main roasting furnace (9); start the T12 burner (22), when the top temperature of the main roasting furnace (9) reaches 400 °C, start the V08 burner (23), then start the V19 main burner (24); when the temperature at the top of the main roasting furnace (9) reaches 700°C, start the electronic quantitative feeder (2) and feeder (2- 1), when the temperature in the main roasting furnace (9) is stable, close the T12 burner (22); Step 3: After weighing and measuring the fly ash containing attached water from the bottom of the silo (1) through the electronic quantitative feeder (2) and the feeder (2-1), It is sent from the feeder (2-1) to the dryer (3) and exchanges heat with the hot flue gas from the secondary cyclone preheater (8). The temperature of the fly ash after heat exchange is 140~200°C. The attached water detaches and enters the primary cyclone preheater (7) with the flue gas. After gas-solid separation, it enters the secondary cyclone preheater (8) from the outlet of the primary cyclone preheater (7) for further preheating and incorporation. Solid separation, the preheated and separated fly ash enters the bottom of the main roasting furnace (9) from the outlet of the secondary cyclone preheater (8); Step 4: The cold air is preheated to 600~800°C through the third-stage cyclone cooler (14), the second-stage cyclone cooler (13), and the first-stage cyclone cooler (12) and enters the main roasting furnace (9). The fly ash in the furnace (9) is fully mixed with the hot air, and is roasted by the high-temperature flue gas heated by the V19 main burner (24) in the main roasting furnace (9). The temperature of the main roasting furnace (9) is controlled to be between 700 and At 1000°C, the residual carbon in the fly ash is burned out in the main roasting furnace (9), and the fixed water and hydrogen chloride in the fly ash are removed; Step 5: In the main roasting furnace (9), fly ash is roasted by high-temperature flue gas and rises along the furnace to the top of the furnace with the high-temperature flue gas and then enters the cyclone separator (10); Step 6: The fly ash separated from gas and solid in the cyclone separator (10) enters the retention tank (11), and the separated high-temperature flue gas enters the secondary cyclone preheater (8); Step 7: The fly ash is further dechlorinated in the retention tank (11) to completely remove the hydrogen chloride in the fly ash. The dechlorinated fly ash is passed through the first-level cyclone cooler (12) and the second-level cyclone cooler. (13), the three-stage cyclone cooler (14) is cold-sent into the final cooler (15); Step 8: The fly ash is finally cooled in the final cooler (15). The fly ash is cooled to below 80°C and sent to the fly ash product bin through the pneumatic transfer pump (16); Step 9: The flue gas discharged from the first-level cyclone preheater (7) enters the dust collector (17) for dust collection. The dust content of the dust-cleaned flue gas reaches the standard and is sent to the water washing tower (26). The dust collected by the dust collector (17) The fly dust is sent to the ash bin (19) through the ash return conveyor (18), and is evenly sent into the dryer (3) by the ash return impeller (20); Step 10: In the water washing tower (26), the hydrogen chloride gas in the flue gas is greatly absorbed by the water. The washed flue gas then enters the neutralization tower (27) and is neutralized by the sodium hydroxide alkali solution. The purified flue gas It is sent into the chimney (30) through the exhaust fan (29), and finally discharged into the atmosphere. 14. The method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash according to claim 13, characterized in that: the load of the suspension roasting device is increased by increasing the opening of the leaf valve (28) and increasing the V19 main combustion. The heat load of the device (24) is realized by increasing the feeding amount of the electronic quantitative feeder (2). The three factors are realized by observing the temperature at the top of the roasting main furnace (9) and the flue gas temperature at the outlet of the dust collector (17). match. 15. The method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash according to claim 13, characterized in that: in the step 3, the fly ash in the silo (1) is the powder after acid leaching to remove impurities. Coal ash; the proportion of attached water in fly ash is 3% to 80%. 16. The method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash according to claim 13, characterized in that: in the steps 4 and 7, the total removal rate of hydrogen chloride in fly ash is 99.5%. The chlorine rate is achieved by controlling the roasting temperature of the fly ash in the main roasting furnace (9) and controlling the residence time of the fly ash in the retention tank (11). 17. The method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash according to claim 13, characterized in that: in step 8, the final cooler (15) uses air to directly or indirectly cool fly ash, or uses Water indirectly cools fly ash; When the final cooler (15) uses air for direct or indirect cooling, the air enters the final cooler (15) through the second air valve (6) to exchange heat with the fly ash. The air enters by adjusting the opening of the second air valve (6). The flow rate of air in the final cooler (15), the hot air after heat exchange returns to the dryer (3) through the cooling outlet of the final cooler (15) for heat recovery; When the final cooler (15) adopts water indirect cooling, the amount of cooling water entering the final cooler (15) is controlled by adjusting the opening of the water flow regulating valve, thereby controlling the final cooling temperature of the fly ash; after cooling, the The cooling water or steam is sent to the circulating water cooling system or steam network. 18. The method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash according to claim 13, characterized in that: in the step 10, the water washing tower (26) uses high-intensity atomized water to wash the flue gas, and the flue gas is More than 90% of the hydrogen chloride in the flue gas is absorbed, and the neutralization tower (27) uses sodium hydroxide alkali solution to neutralize and remove the remaining hydrogen chloride in the flue gas. 19. The method for producing silicon-aluminum alloy raw materials by dechlorinating fly ash according to claim 13, characterized in that: in the steps 9 and 10, the dust content of the flue gas at the outlet of the dust collector (17), the neutralization tower (27) Export flue gas containing HCL meets national environmental protection requirements. 20. A method for producing dry fly ash, characterized in that: the method uses the suspension roasting device of claim 1 for production, and includes the following steps: Step 11: Open the flue gas cut-off valve (4), so that the outlet of the second-level cyclone preheater (8) and the air inlet of the dryer (3) are in a passage state; open the plug-in valve B (7-2), so that the first-level cyclone The outlet of the preheater (7) is connected to the second pneumatic conveying pump (25); other moving equipment and valves are stopped and closed; Step 12: Start the exhaust fan (29), slightly open the leaf valve (28), there will be a slight negative pressure in the main roasting furnace (9), start the T12 burner (22), when the top temperature of the main roasting furnace (9) reaches 300 °C, start the V08 burner (23), then start the V19 main burner (24); when the inlet temperature of the dryer (3) reaches 250~350°C, start the electronic quantitative feeder (2), feeder ( 2-1); Step 13: After the fly ash containing attached water is weighed and measured from the bottom of the silo (1) by the electronic quantitative feeder (2), it is sent to the dryer (3) from the feeder (2-1) and mixed with The hot flue gas from the secondary cyclone preheater (8) is heat exchanged. The temperature of the fly ash after heat exchange is 140~200°C. The attached water detaches and enters the primary cyclone preheater (7) with the flue gas. The solid-separated fly ash enters the pneumatic conveying pump two (25) through the discharge port of the first-level cyclone preheater (7) and the gate valve B (7-2), and then is sent to the dry fly ash silo; Step 14: The cold air enters the first-level cyclone cooler (12) through the third-level cyclone cooler (14) and the second-level cyclone cooler (13), is heated by the T12 burner (22), and passes through the first-level cyclone cooler (12). Enters the air inlet at the bottom of the main roasting furnace (9); the heated hot air is further heated by the V19 main burner (24) in the main roasting furnace (9), and then passes through the cyclone separator (10) and the secondary cyclone preheater (8) Enter the dryer (3); Step 15: The dried fly ash in the dryer (3) is carried by the hot flue gas into the first-level cyclone preheater (7) for gas-solid separation. The flue gas discharged from the first-level cyclone preheater (7) enters the dust collector. (17) Dust collection is carried out, and the recovered dust is sent to the ash bin (19) through the ash return conveyor (18), and evenly sent to the dryer (3) through the ash return impeller (20); Step 16: The hot flue gas after dust removal by the dust collector (17) enters the water washing tower (26). The hydrogen chloride gas in the flue gas is greatly absorbed by the water. The washed flue gas then enters the neutralization tower (27) to be hydrogenated. The sodium lye is neutralized, and the purified flue gas is sent into the chimney (30) through the exhaust fan (29), and finally discharged into the atmosphere. 21. The method for producing dry fly ash according to claim 20, characterized in that: the ability of the suspended roasting device to dry fly ash is achieved by increasing the opening of the leaf valve (28) and increasing the V19 main burner. (24) The heat load is achieved by increasing the feeding amount of the electronic quantitative feeder (2); the fly ash drying quality is controlled by controlling the air outlet temperature of the first-level cyclone preheater (7). 22. The method for producing dry fly ash according to claim 20, characterized in that: in the step 13, the fly ash in the silo (1) is the fly ash after impurity removal by acid leaching; The proportion of attached water in the ash is 3% to 80%. 23. The method for producing dry fly ash according to claim 20, characterized in that: in the step 16, the water washing tower (26) washes the flue gas with high-strength atomized water to remove more than 90% of the flue gas. The hydrogen chloride is absorbed, and the neutralization tower (27) uses sodium hydroxide alkali solution to neutralize and remove the remaining hydrogen chloride in the flue gas. 24. The method for producing dry fly ash according to claim 20, characterized in that: in the steps 15 and 16, the dust content of the flue gas at the outlet of the dust collector (17), the flue gas at the outlet of the neutralization tower (27) The HCL contained in the gas meets the national environmental protection requirements. 25. A method for producing dry fly ash, characterized in that: the method uses the suspension roasting device of claim 1 for production, and includes the following steps: Step 21: Open the air valve one (5), close the flue gas cut-off valve (4), so that the atmosphere and the dryer (3) are in the channel state, open the gate valve B (7-2), and other moving equipment and valves are in the Stopped, closed state; Step 22: Start the exhaust fan (29), open the 20% leaf valve (28), and start the T11 burner (21); Step 23: Start the electronic quantitative feeder (2) and feeder (2-1), and weigh the fly ash containing attached water from the bottom of the silo (1) through the electronic quantitative feeder (2) , sent to the dryer (3) from the feeder (2-1); the air entering from the air valve one (5) mixes with the high-temperature flue gas generated by the T11 burner (21) and then enters the dryer (3). The fly ash is dried by the hot flue gas; the temperature of the fly ash after heat exchange is 140~200°C, and the attached water is separated here. The dried fly ash is separated from gas and solid in the first-level cyclone preheater (7). The gate valve B (7-2) enters the pneumatic conveying pump two (25), and is sent to the dry fly ash silo by the pneumatic conveying pump two (25); Step 24: The flue gas after gas-solid separation in the first-level cyclone preheater (7) is discharged from the outlet of the first-level cyclone preheater (7) and sent to the dust collector (17). The flue gas after dust removal contains a small amount of hydrogen chloride. In the water washing tower (26), the hydrogen chloride gas in the flue gas is absorbed by water. The washed flue gas then enters the neutralization tower (27) and is neutralized by sodium hydroxide alkali solution. The purified flue gas passes through the exhaust fan (29) Send it into the chimney (30) and discharge it into the atmosphere; Step 25: The dust recovered by the dust collector (17) is sent to the ash bin (19) through the ash return conveyor (18), and evenly sent into the dryer (3) through the ash return impeller (20). 26. The method for producing dry fly ash according to claim 25, characterized in that: in the step 23, the fly ash in the silo (1) is the fly ash after impurity removal by acid leaching; The proportion of attached water in the ash is 3% to 80%. 27. The method for producing dry fly ash according to claim 25, characterized in that: in the step 24, the water washing tower (26) washes the flue gas with high-strength atomized water to remove more than 90% of the flue gas. The hydrogen chloride absorbed by the neutralization tower (27) uses sodium hydroxide alkali solution to neutralize and remove the remaining hydrogen chloride in the flue gas; the dust content of the flue gas at the outlet of the dust collector (17), the dust content of the flue gas at the outlet of the neutralization tower (27) HCL all meet national environmental protection requirements.