Fly ash and sludge high-temperature sintering building material utilization process and application thereof

Abstract

The application discloses a kind of fly ash and sludge high-temperature sintering building material utilization process, comprising the following steps: S1 fly ash and sludge are mixed, and granulation is carried out after adding auxiliary materials;S2 drying after granulation, control moisture content;S3 then preheating;S4 preheated material enters hearth and is heated, and material gathers and forms sintered body;S5 sintered body cooling separation;S6 after secondary separation, solid high-temperature sintering;S7 cooling crushing;S8 after secondary separation, flue gas cooling coagulation into salt, salt refining, un-settled flue gas removes dust, desulfurization, denitration is discharged after reaching standard.The application fly ash, sludge and smelting secondary aluminum ash jointly act, and the sintered body prepared obtains high activity index, meets the standard of cement active material S75.By introducing fluxing agent sodium sulfate or mirabilite, the glass content of high-temperature sintered body is increased, and the performance of material after high-temperature sintering is further improved.The removal rate of chloride ions is improved.The energy consumption is reduced, and it is green and environment-friendly.

Description

Technical Field

[0001] This invention relates to a high-temperature sintering process for building materials from fly ash and sludge, and its application, specifically relating to B09B, and in the field of solid waste destruction or the transformation of solid waste into useful or harmless substances. Background Technology

[0002] Dioxins and heavy metals are produced during the incineration of municipal solid waste. During re-incineration, heavy metals can still enter the flue gas and be captured, forming new hazardous waste, "fly ash." Currently, there are generally three routes for treating fly ash: high-temperature sintering, high-temperature melting, and co-processing in cement kilns after water washing and dechlorination. High-temperature plasma melting is commonly used, but this technology is currently not mature and its treatment effect is unstable. Co-processing in cement kilns after water washing and dechlorination consumes a lot of energy, and the resulting particles completely lose their activity, making them unsuitable for reuse in building materials. Traditional processes use rotary kilns for high-temperature sintering, which is energy-intensive, has low throughput, and unstable production.

[0003] Chinese invention patent CN201710445049.1 discloses a fly ash sintered brick and its preparation process. Fly ash, coal gangue, and shale are crushed and mixed evenly with papermaking sludge. The mixture is then aged, shaped, dried, and fired to obtain the finished fly ash sintered brick. This method not only reduces raw material costs but also reduces fly ash pollution. However, the resulting building material has a low activity index and poor compressive strength. Chinese invention patent CN201410324537.3 discloses a waste incineration fly ash sintering and volume reduction treatment technology. By adding a dechlorination flux to the fly ash, the volatilization of heavy metals and the decomposition of dioxins are enhanced. Heavy metals and chlorides are highly concentrated in the secondary fly ash within a relatively low temperature range. Further pollutant enrichment and fly ash reduction are achieved through water washing of the secondary fly ash. However, this method has high energy consumption, and the activity is completely lost after washing, preventing the reuse of fly ash in building materials. Summary of the Invention

[0004] To reduce the energy consumption of fly ash treatment and to enable the high-temperature sintering of fly ash into building materials, the first aspect of this invention provides a process for the high-temperature sintering and utilization of fly ash and sludge into building materials, comprising the following steps:

[0005] S1 mixes fly ash and sludge, adds auxiliary materials, and then granulates the mixture;

[0006] After S2 granulation, the material is dried by indirect solar thermal drying in a tunnel kiln and waste heat drying from flue gas to control the moisture content.

[0007] S3 then enters the preheated external bed, where it is preheated with hot air.

[0008] The preheated material from S4 falls into the return leg of the circulating fluidized bed in the furnace in a fluidized manner, mixes with the circulating material in the circulating fluidized bed, and then falls into the dense phase zone of the circulating fluidized bed boiler, where it is heated and the material aggregates to form a sintered body.

[0009] S5 sintered body is cooled and crushed by collision between particles under the action of airflow. The particles enter the first-stage cyclone separator. Particles with a mass fraction of 90-95% enter the feed pipe, pass through the return feeder J valve and the feed leg, and return to the fluidized bed furnace.

[0010] S6 particles with a remaining mass fraction of 5-10% enter the secondary cyclone separator. After separation, the solid particles are mixed with coal powder and fall into the high-temperature sintering chamber together.

[0011] The bottom of the S7 high-temperature sintering chamber is vented with high-pressure fluidizing air. The coal powder combustion releases heat, bringing the material to 1350-1450℃. After combustion, the material is cooled, crushed, and sent to the finished product warehouse.

[0012] After separation by the S8 secondary cyclone separator, the flue gas enters the cooling settling chamber, where the temperature drops from 830-880℃ to 280-200℃. The gaseous low-melting-point sodium and potassium salts in the flue gas condense into solid mixed salt particles. The solid mixed salt particles enter the tertiary cyclone separator with the flue gas for settling and separation. The settled solid mixed salt particles then enter the mixed salt refining process.

[0013] In a preferred embodiment, after the three-stage cyclone separator in step S8, the unsettled flue gas enters a bag filter to remove dust, and then undergoes desulfurization and denitrification before being discharged in compliance with emission standards.

[0014] In a preferred embodiment, the high-temperature sintering chamber is an insulated structure, and the bottom is equipped with a rotating tray-type unloading mechanism and a high-pressure fluidizing air distribution plate.

[0015] In a preferred embodiment, the flue gas separated by the secondary cyclone separator in step S8 enters the cooling settling chamber, where the temperature drops from 850°C to 250°C, and the gaseous low-melting-point sodium and potassium salts in the flue gas condense into solid mixed salt particles. The solid mixed salt particles enter the tertiary cyclone separator with the flue gas for settling and separation, and the settled solid mixed salt particles enter the mixed salt refining process.

[0016] In a preferred embodiment, the mass ratio of fly ash to sludge is 1:(0.8-1.2).

[0017] During the experiment, the applicant discovered that when raw ash, sludge, and secondary alumina ash were mixed and sintered, the resulting sintered body had a high activity index, meeting the S75 standard for cement active materials. The applicant speculates that the possible reason is that by introducing secondary alumina ash and sintering at high temperature, glassy minerals can be obtained. These glassy minerals, under normal temperature and water conditions, can react with hydrated lime or calcium hydroxide or gypsum precipitated from cement hydration to generate hydration products with gel properties. These products act as physical fillers in the cement, thereby improving the compressive strength of the material and resulting in a high activity index that meets the S75 standard for cement active materials.

[0018] In a preferred embodiment, the excipients include one or a combination of several of the following: reducing agent, melting agent, and triggering agent.

[0019] In a preferred embodiment, the fly ash, sludge and auxiliary materials comprise, by weight percentage: 40-45% fly ash, 40-45% sludge, 5-10% reducing agent, 1-5% fluxing agent, and 10-20% triggering agent.

[0020] As a preferred embodiment, the auxiliary materials also include waste activated carbon and quartz powder.

[0021] In a preferred embodiment, the quartz powder is derived from general solid waste, specifically artificial quartz sludge powder.

[0022] In a preferred embodiment, the fluxing agent is selected from one or a combination of sodium sulfate or sodium sulfate, and the fluxing agent accounts for 1-5% of the total mass.

[0023] In a preferred embodiment, the triggering agent is secondary aluminum ash from smelting, wherein the components of the secondary aluminum ash from smelting include, by weight percentage, 65-75% alumina, 5-10% sodium chloride, 3-10% sodium fluoroaluminate, and 10-12% elemental aluminum.

[0024] Aluminum ash is the surface crust and slag produced when aluminum is in a molten state during electrolysis, recycling, and deep processing. Compared to waste incineration fly ash, aluminum ash contains not only a large amount of aluminum but also a certain amount of fluorine. During co-processing, it can combine with the abundant calcium (Ca) present in fly ash. Using 10-20% secondary aluminum ash ensures that the fluorine in the aluminum ash is fully solidified. Aluminum ash also contains AlN, which reacts with moisture to generate ammonia when mixed with sludge. The high alkaline content of fly ash further promotes the release of ammonia, and residual ammonia nitrogen may enter the incinerator, increasing the pressure on denitrification during incineration. During the co-thermal treatment of waste incineration fly ash and aluminum ash, CaCO3, Ca(ClO)2, and KFe(SO4)2 decompose during heat treatment, and most of the chloride salts enter the flue gas. In aluminum ash, Al combines with other components to form aluminum-containing mineral phases such as Ca2Al2SiO7, Na6(AlSiO4)6, and Na3AlF6, while the original Al(OH)3 decomposes into oxides. At high temperatures, a large amount of chlorine volatilizes, but due to the combination with elements such as Na, K, and Ca, and the formation of aluminum-containing mineral phases, the volatilization rates of Na, K, and Ca decrease, while the production of HCl increases, necessitating an enhanced deacidification process. Aluminum ash contains a large amount of aluminum, which can serve as an aluminum source to promote vitreous formation and improve the solidification effect of heavy metals. Its impurities do not introduce new heavy metals, and any adverse effects can be mitigated through adjustments. Adding aluminum ash as an aluminum source can improve the co-thermal treatment effect of waste incineration fly ash and sludge, while also facilitating the disposal of aluminum ash.

[0025] In a preferred embodiment, the reducing agent is pulverized coal.

[0026] During the experiment, the applicant discovered that by adding fluxing agents such as sodium sulfate or mirabilite to the process, the content of glass in the high-temperature sintered body could be increased, and the quality of the powder after grinding of the high-temperature sintered body could be improved. The possible reason is that after the introduction of fluxing agent sodium sulfate, the reducing agent begins to release heat during the sintering stage. The introduction of sodium sulfate can make the powder reach the melting point quickly, increase the melting rate inside the powder, increase the melting ratio of powder particles, and cause the powder to aggregate to form glass, thereby increasing the content of glass in the sintered body.

[0027] Furthermore, the circulating material is heated to an external temperature of 950-1050℃, which allows the material to heat up rapidly. The preheated material and the circulating material fall into the dense phase zone of the circulating fluidized bed boiler, where the material heats up quickly, thus improving the removal rate of chloride ions.

[0028] In a preferred embodiment, the moisture content in step S2 is 25-30%.

[0029] In a preferred embodiment, the hot air temperature in step S3 is 200-240℃, and the preheated temperature is 140-160℃.

[0030] In a preferred embodiment, the temperature of the circulating material in the circulating fluidized bed in step S4 is 950-1050℃, the temperature of the upper part of the furnace is 1100-1150℃, the flue gas velocity in the furnace is 1.0-1.5m / s in the hot state, the height of the middle and upper part is 5-8m, and the residence time of the flue gas in the high-temperature section is 5-8s.

[0031] The specific reaction in step S4 is as follows: The preheated material falls into the return leg of the circulating fluidized bed in a fluidized state. In the return leg, it mixes with the circulating fluidized bed material at 950℃-1050℃. It then falls into the dense phase zone of the circulating fluidized bed boiler. After being heated to above 600℃, the reducing agent inside the material begins to release heat, and the temperature inside the material particles rapidly rises to 1400℃-1500℃, reaching the melting point of the main components. The powder particles partially melt, and the powder aggregates to form a sintered body. During the circulating sintering process, chloride ions in the material are separated in the form of gaseous sodium chloride, potassium chloride, and sodium sulfate molecules.

[0032] In a preferred embodiment, in step S5, particles cooled to 950-1050℃ and crushed to a particle size of 100±50μm enter the primary cyclone separator. Particles with a particle size of 40±10μm enter the secondary cyclone separator.

[0033] In a preferred embodiment, the cooling temperature of the moving bed cooler is 200-250°C.

[0034] During the high-temperature sintering process, dioxins are incinerated; low-melting-point sodium chloride, potassium chloride, sodium sulfate, and potassium sulfate salts are vaporized and separated from the sintered body.

[0035] After the secondary cyclone separation, the high-temperature flue gas, carrying gaseous sodium and potassium salts and fine dust, enters the cooling and settling chamber, where the flue gas temperature drops to 250°C to prevent the resynthesis of dioxins.

[0036] The ambient temperature primary air is heated to 200℃-250℃ during this process to form medium-temperature primary air. This medium-temperature primary air then enters the high-temperature air preheater (a structure utilizing the furnace's insulation layer), where the hot air is heated to 600-650℃. The high-temperature primary air then passes through the air cap and enters the furnace, maintaining fluidization while supporting the heat release from material combustion. A small amount of high-temperature primary air is also used as fluidizing air to preheat the external bed, saving energy consumption.

[0037] Gaseous low-melting-point sodium and potassium salts in the flue gas condense into solid mixed salt particles, which then enter a three-stage low-temperature cyclone separator. Non-sodium and potassium salt dust not separated in the two-stage cyclone separator remains unseparated in the three-stage separator and is collected by a bag filter with the flue gas. The fly ash collected by the bag filter is returned to the upstream process for regranulation and calcination.

[0038] The sodium and potassium salts collected by the three-stage cyclone separator, with a potassium salt content of 15%-25% based on the original ash salt content, are sold to potash fertilizer production enterprises.

[0039] The second aspect of the present invention provides an application of a high-temperature sintering process for building materials from fly ash and sludge, which is applied to the treatment of fly ash from waste incineration.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] (1) The high-temperature sintering building material utilization process of fly ash and sludge described in this invention, with the combined action of fly ash, sludge and secondary aluminum ash from smelting, produces a sintered body with a high activity index, meeting the S75 standard for cement active materials.

[0042] (2) The high-temperature sintering building material utilization process of fly ash and sludge described in this invention increases the glass content of the high-temperature sintered body by introducing fluxing agent sodium sulfate or mirabilite, thereby further improving the performance of the material after high-temperature sintering.

[0043] (3) The high-temperature sintering building material utilization process of fly ash and sludge described in this invention uses an external surface temperature of 950-1050℃ for the circulating material, which can rapidly raise the temperature of the material. The preheated material and the circulating material fall into the dense phase zone of the circulating fluidized bed boiler, and the material rapidly raises the temperature, thereby improving the removal rate of chloride ions.

[0044] (4) The high-temperature sintering building material utilization process of fly ash and sludge described in this invention utilizes the high-temperature flue gas in the furnace to indirectly heat the air, maintain the temperature of the preceding process, reduce energy consumption, and is green and environmentally friendly.

[0045] (5) The high-temperature sintering building material utilization process of fly ash and sludge described in this invention not only produces building material products with high activity index, but also produces metal salts for use in the fertilizer industry. Attached Figure Description

[0046] Figure 1 This is a flowchart of the device in Embodiment 3 of this application;

[0047] Figure 2 This is a flowchart of the mixed salt refining process after processing in Example 3 of this application;

[0048] Figure 3The diagram shows the equipment flow chart for the fly ash washing and desalination process in Example 6.

[0049] In the diagram: 1. Auxiliary material tank; 2. Fly ash tank; 3. Sludge tank; 4. Mixing and feeding equipment; 5. Feed silo; 6. Primary cyclone separator; 7. Secondary cyclone separator; 8. Tertiary cyclone separator; 9. High-temperature sintering chamber; 10. Dust collector; 11. Cooling and settling chamber. Detailed Implementation

[0050] Example 1

[0051] A process for the high-temperature sintering and utilization of fly ash and sludge in building materials includes the following steps:

[0052] S1 mixes the fly ash in 2 fly ash tanks and the sludge in 3 sludge tanks, adds the auxiliary materials in 1 auxiliary material tanks, and then mixes them through 4 mixing and granulation equipment;

[0053] After S2 granulation, the material is dried by indirect solar thermal drying in a tunnel kiln and waste heat drying from flue gas to control the moisture content.

[0054] S3 then enters the preheated external bed, where it is preheated with hot air.

[0055] After preheating in S4, the material falls into the furnace circulating fluidized bed return leg in a fluidized manner through the 5 feed hopper, mixes with the circulating fluidized bed material, and then falls into the dense phase zone of the circulating fluidized bed boiler, where it is heated and the material aggregates to form a sintered body.

[0056] S5 sintered body is cooled and crushed by collision between particles under the action of airflow. The particles enter the 6-stage cyclone separator. Particles with a mass fraction of 90-95% enter the discharge pipe, pass through the return valve J and discharge leg, and return to the fluidized bed furnace.

[0057] Particles with a remaining mass fraction of 5-10% in S6 enter the secondary cyclone separator 7. After separation, the solid particles are mixed with coal powder and fall into the high-temperature sintering chamber 9 together.

[0058] The bottom of the S7 high-temperature sintering chamber 9 is vented with high-pressure fluidizing air. The coal powder combustion releases heat, bringing the material to 1400℃. After combustion, the material is cooled, crushed, and sent to the finished product warehouse.

[0059] After separation by the S8 secondary cyclone separator 7, the flue gas enters the cooling settling chamber 11, where the temperature drops from 850℃ to 250℃. The gaseous low-melting-point sodium and potassium salts in the flue gas condense into solid mixed salt particles. The solid mixed salt particles enter the tertiary cyclone separator 8 with the flue gas for settling and separation. The settled solid mixed salt particles then enter the mixed salt refining process.

[0060] After the three-stage cyclone separator 8 in step S8, the unsettled flue gas enters the bag filter 10 to remove dust from the flue gas, and then passes through desulfurization and denitrification before being discharged in compliance with standards.

[0061] The high-temperature sintering chamber is an insulated structure, and its bottom is equipped with a rotating tray-type unloading mechanism and a high-pressure fluidizing air distribution plate.

[0062] The fly ash, sludge, and auxiliary materials comprise, by weight percentage: 45% fly ash, 45% sludge, and 10% reducing agent.

[0063] The reducing agent is pulverized coal; the sludge is sludge with a water content of 80 wt%.

[0064] The moisture content in step S2 is 25%.

[0065] In step S3, the hot air temperature is 220°C, and the preheated temperature is 150°C.

[0066] In step S4, the temperature of the circulating material in the circulating fluidized bed is 1000±50℃, the temperature of the upper part of the furnace is 1125±25℃, the flue gas velocity in the furnace is 1.25m / s under hot conditions, the height of the middle and upper part is 8m, and the residence time of the flue gas in the high-temperature section is 8s.

[0067] In step S5, particles cooled to 1000±50℃ and crushed to a diameter of 100±50μm enter the primary cyclone separator. Particles with a diameter of 40±10μm enter the secondary cyclone separator.

[0068] The moving bed cooler has a cooling temperature of 225°C.

[0069] Example 2

[0070] A high-temperature sintering process for building materials utilization of fly ash and sludge is described. The specific implementation method is the same as in Example 1, except that the fly ash, sludge and auxiliary materials include, by weight percentage: 40% fly ash, 40% sludge, 5% reducing agent and 15% triggering agent.

[0071] The reducing agent is pulverized coal; the sludge is sludge with a water content of 80 wt%; the triggering agent is secondary aluminum ash from smelting, wherein the components, by weight percentage, include 65-75% alumina, 5-10% sodium chloride, 3-10% sodium fluoroaluminate, and 10-12% elemental aluminum.

[0072] Example 3

[0073] A high-temperature sintering process for building materials utilization of fly ash and sludge is described. The specific implementation method is the same as in Example 1, except that the fly ash, sludge and auxiliary materials include, by weight percentage: 25% fly ash, 48% sludge, 3% reducing agent, 13% triggering agent, 3% fluxing agent, 3% waste activated carbon and 5% quartz powder.

[0074] The fluxing agent is sodium sulfate; the reducing agent is pulverized coal; the sludge is sludge with a water content of 80 wt%; the triggering agent is secondary aluminum ash from smelting, the components of which, by weight percentage, include 65-75% alumina, 5-10% sodium chloride, 3-10% sodium fluoroaluminate, and 10-12% elemental aluminum. The quartz powder is derived from general solid waste, specifically artificial quartz sludge powder.

[0075] See equipment flow chart Figure 1 The flowchart for the post-processing salt refining process is shown below. Figure 2 .

[0076] Example 4

[0077] A process for utilizing fly ash and sludge in high-temperature sintering building materials, with the same implementation method as Example 1, except that the temperature of the circulating material in the circulating fluidized bed in step S4 is 775±25℃.

[0078] Example 5

[0079] A process for utilizing fly ash and sludge in high-temperature sintering building materials, with the same implementation method as Example 1, except that the temperature of the circulating material in the circulating fluidized bed in step S4 is 815±15℃.

[0080] Example 6

[0081] This technology employs fly ash washing and desalination, utilizing a three-stage countercurrent rinsing process to wash fly ash, kiln ash, or similar powdery materials to remove soluble substances. The process consists of four subsystems: a fly ash washing and desalination system, a washing liquid purification system, an evaporation and salt production system, and a drying system. First, the fly ash undergoes pulping, washing, and separation in the fly ash washing and desalination system. The separated mud cake is dried and then sent to a resource recovery facility for disposal. The separated liquid is treated by the washing liquid purification system and then sent to the evaporation and salt production system to crystallize and separate potassium and sodium salts from the fly ash washing liquid, producing industrial by-products. The condensate is recovered and returned to the process system for reuse. (Refer to existing fly ash washing and desalination technology.) Equipment diagram reference. Figure 3 .

[0082] Performance testing

[0083] 1. Activity Index: The activity index of the final products of Examples 1-2 was obtained by referring to the test of GB / T 18046-2017 Appendix A (Regulatory Appendix) Determination of Activity Index, Flowability Ratio and Initial Setting Time Ratio of Slag Powder.

[0084] 2. Vitreous content: The vitreous content of the final products of Examples 1-3 was determined by referring to Appendix C (Normative Appendix) of GB / T 18046-2017, which specifies the method for determining the vitreous content of slag powder.

[0085] 3. Chloride ion residue: The chloride ion residue of the final products of Examples 3-5 was determined by referring to the chemical analysis method of chloride ions in cement (JC / T 1073-2008).

[0086] The test results are shown in Table 1.

[0087] Table 1

[0088]

Claims

1. A process for the high-temperature sintering and utilization of fly ash and sludge in building materials, characterized in that, Includes the following steps: S1 mixes fly ash and sludge, adds auxiliary materials, and then granulates the mixture; the auxiliary materials include a reducing agent and a triggering agent; the reducing agent is pulverized coal, and the triggering agent is secondary aluminum ash from smelting. After S2 granulation, the material is dried by indirect solar thermal drying in a tunnel kiln and waste heat drying from flue gas to control the moisture content. S3 then enters the preheated external bed, where it is preheated with hot air. The preheated material in S4 falls into the return leg of the circulating fluidized bed furnace in a fluidized manner, mixes with the circulating fluidized bed material, and then falls into the dense phase zone of the circulating fluidized bed boiler. Under heat, the material aggregates to form a sintered body; the temperature of the circulating fluidized bed material is 950-1050℃. S5 sintered body is cooled and crushed by collision between particles under the action of airflow. The particles enter the first-stage cyclone separator. Particles with a mass fraction of 90-95% enter the feed pipe, pass through the return feeder J valve and the feed leg, and return to the fluidized bed furnace. Particles with a remaining mass fraction of 5-10% in S6 enter the secondary cyclone separator. The separated solids are mixed with coal powder and fall into the high-temperature sintering chamber together. The bottom of the S7 high-temperature sintering chamber is vented with high-pressure fluidizing air. The coal powder combustion releases heat, bringing the material to 1350-1450℃. After combustion, the material is cooled, crushed, and sent to the finished product warehouse. After separation by the S8 secondary cyclone separator, the flue gas enters the cooling settling chamber, where the temperature drops from 830-880℃ to 280-200℃. The gaseous low-melting-point sodium and potassium salts in the flue gas condense into solid mixed salt particles. The solid mixed salt particles enter the tertiary cyclone separator with the flue gas for settling and separation. The settled solid mixed salt particles then enter the mixed salt refining process.

2. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 1, characterized in that, After the three-stage cyclone separator in step S8, the unsettled flue gas enters the bag filter to remove dust, and then passes through desulfurization and denitrification before being discharged in compliance with standards.

3. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 1, characterized in that, The mass ratio of fly ash to sludge is 1:(0.8-1.2).

4. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 1, characterized in that, The excipients also include a fluxing agent.

5. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 4, characterized in that, The fluxing agent is selected from one or a combination of sodium sulfate or mirabilite, and the fluxing agent accounts for 1-5% of the total mass of fly ash, sludge and auxiliary materials.

6. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 4, characterized in that, The components of the secondary aluminum ash from the smelting process, by weight percentage, include 65-75% alumina, 5-10% sodium chloride, 3-10% sodium fluoroaluminate, and 10-12% elemental aluminum.

7. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 1, characterized in that, The moisture content in step S2 is 25-30%.

8. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 1, characterized in that, In step S3, the hot air temperature is 200-240℃, and the preheated temperature is 140-160℃.

9. The high-temperature sintering building material utilization process for fly ash and sludge according to claim 1, characterized in that, In S4, the temperature of the upper part of the furnace is 1100-1150℃, the hot flow velocity of the flue gas in the furnace is 1.0-1.5m / s, the height of the upper part of the furnace is 5-8m, and the residence time of the flue gas in the high-temperature section of the furnace is 5-8s.

10. An application of the high-temperature sintering building material utilization process of fly ash and sludge according to any one of claims 1-9, characterized in that, It is used in the treatment of fly ash from waste incineration.

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