CN113975919B

CN113975919B - Dry-method chlorine component recovery process based on synergistic treatment of chlorine-containing solid wastes by cement kiln

Info

Publication number: CN113975919B
Application number: CN202111158906.2A
Authority: CN
Inventors: 吴高明; 吴晓晖; 吴轶可; 卫书杰
Original assignee: WUHAN WUTUO TECHNOLOGY CO LTD
Current assignee: WUHAN WUTUO TECHNOLOGY CO LTD
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-03-28
Anticipated expiration: 2041-09-30
Also published as: CN113975919A

Abstract

The invention discloses a dry-method chlorine component recovery process for cooperatively treating chlorine-containing solid waste based on a cement kiln, which solves the problems of long process, high energy consumption, high equipment investment and operation cost and environmental pollution in the conventional wet-method chlorine-containing component treatment. The technical scheme includes that solid waste containing chlorine components enters a cement production line, the chlorine components are gasified and enter flue gas under the high-temperature environment in a rotary kiln, part of the flue gas is led out from a kiln head flue gas hood of the rotary kiln, the led-out part of the flue gas is sent into a cooling tower after being dedusted by a dry method to directly exchange heat with potassium chloride powder materials for cooling, the chlorine components in the flue gas are condensed and enter the potassium chloride powder materials, the flue gas after heat exchange is discharged from the top of the cooling tower, and the potassium chloride powder materials after heat exchange are discharged from the bottom of the cooling tower. The method has the advantages of simple process, low investment cost and operation cost, environmental friendliness, energy conservation, consumption reduction and effective recovery of potassium chloride products.

Description

Dry-method chlorine component recovery process based on cooperative disposal of chlorine-containing solid wastes by cement kiln

Technical Field

The invention belongs to the field of solid waste treatment, relates to a resource recycling process of potassium chloride during synergistic treatment of chlorine-containing solid waste by a cement kiln, and particularly relates to a dry recycling process of chlorine components in synergistic treatment of chlorine-containing solid waste based on the cement kiln.

Background

In the industrial structure adjustment catalog released by the revision of the national committee for improvement in 2019, fly ash co-processed by a cement kiln is listed as a first item of building material encouragement. The fly ash is derived from municipal waste incineration power plants, is a typical hazardous waste containing chlorine components (potassium chloride + sodium chloride), has a chlorine content of 10 percent, and is even higher [ Zhang Lei, zhang Yunze ] the application of sodium and potassium salt separation in a fly ash cement kiln synergistic treatment line.

The cement kiln has the characteristics of high temperature, large heat capacity and thermal inertia, long residence time in a high-temperature logistics area, thorough decomposition of harmful components and the like, and the cement kiln is utilized to cooperatively treat solid wastes such as domestic garbage, fly ash and the like, so that the mainstream development direction of urban solid waste disposal is provided. According to the production site tracking analysis of synergistic treatment of solid waste in the cement kiln [ Li Guojiang, han Tao, xiaoshengdan, and the like. That is, in cement production lines, the area at 800-900 ℃ is prone to skinning and plugging.

Theoretically, KCl, naCl, caCl ₂ The melting points of the crystals are 770 ℃, 801 ℃, 772 ℃ and 1420 ℃, 1465 ℃ and 1935 ℃ respectively, so that theoretically, the chlorine-containing compounds can be gasified only by heating to at least 1400 ℃. However, since the cement raw material is a mixture of a plurality of inorganic salt compounds, theoretically, the salt mixture forms a eutectic point component, and the gasification temperature is also reduced. According to the analysis of the skinning and blocking phenomena occurring in the actual production, the boiling point of the mixed salts containing the chlorine component is between 800 and 900 ℃. Therefore, during the cement production process, the chlorine-containing component is gasified at high temperature, condensed at 800-900 ℃ and enters the high-temperature area in the cement production unit again along with the cement raw material, thereby forming cyclic enrichment of the chlorine-containing component in the cement production unit.

Li Ruiqing et al [ Li Ruiqing, et al, naCl-CaCl ₂ -BaCl ₂ And NaCl-KCl-BaCl ₂ Calculation of ternary molten salt phase diagram chemical metallurgy 1988,9 (2): 10-16 ] NaCl-KCl-BaCl is obtained by analyzing the phase diagram of the multicomponent molten salt ₂ In the ternary molten salt system, the minimum eutectic parameter is 542 ℃ and the calculated value of the minimum eutectic is 535 ℃. In the production process of preparing metal lithium by electrolyzing molten salt LiCl, a proper amount of KCl crystal is added, so that the temperature of the electrolytic bath can be reduced to 400 ℃, and the production condition is improved.

Bao Wenzhong, et al, analyzed the chlorine circulation mechanism in cement production [ Bao Wenzhong, et al, cement kiln bypass ventilation technology and waste heat utilization profile, cement technology, 2013, (6): 96-99 ]. The chlorine entering the burning zone is almost totally volatilized, only a very small part is carried away by the clinker, and the chloride volatilized from the raw meal and the fuel can form alkali chloride with alkali in the raw meal or with alkali steam which enters the kiln gas and is not combined with the sulfur. Chlorine brought into kiln gas in the volatilization process is more prone to react with potassium to generate potassium chloride, and the excessive chlorine can form sodium chloride with sodium only after the potassium chloride is formed. At temperatures between 800 ℃ and 900 ℃, the vapor pressure of the compound approaches zero, i.e., the compound almost completely condenses on the surface of the raw meal, causing skinning and plugging in certain areas or equipment. The alkali chloride has a lower vapor pressure than other alkali compounds and reaches its boiling point at a firing temperature below 1450 ℃ in the kiln, so that it re-volatilizes soon after entering the kiln. Therefore, when the chlorine content in the raw meal exceeds a certain limit, the alkali circulation increases sharply, leading to severe skinning in preheaters or pipelines at temperatures in the range of 800 ℃ to 1000 ℃, while alkali chloride can also form a low-melting mixture with alkali sulfate, adhere to the surface of the raw meal, reduce the flowability of the raw meal, leading to increased skinning. In the cement kiln, chlorine elements exist to promote the circulation of alkali.

Due to the restriction of the inherent characteristics of the cement production process, after the wastes containing potassium chloride components such as household garbage, fly ash and the like enter the rotary cement kiln production line for cooperative treatment, the chlorine-containing components (mainly potassium chloride and sodium chloride) are circulated and enriched in the cement production line, and ring formation and blockage in the rotary cement kiln are caused in serious cases, so that the normal production of the rotary cement kiln is influenced. Meanwhile, chlorine elements brought along with the waste materials finally enter the cement clinker, so that the content of chloride ions in the cement is increased, and the quality of the water cement is influenced. The efficiency of the rotary cement kiln in co-processing chlorine-containing waste is always at a low level.

In order to improve the efficiency of the rotary cement kiln for cooperatively treating chlorine-containing waste such as fly ash and the like, two technical routes of pretreatment of the chlorine-containing waste and bypass air discharge treatment of cement production are adopted at present.

The chlorine-containing waste pretreatment is to perform dechlorination pretreatment on the chlorine-containing waste before the chlorine-containing waste enters the cement production unit, and the dechlorinated solid residue enters the cement production unit for recycling. Because a lot of chlorine-containing wastes are not suitable for pretreatment, the chlorine-containing wastes can only directly enter a cement production unit and are separated out through bypass air discharge treatment.

At present, wet treatment processes such as water washing or acid washing are adopted in the pretreatment scheme of the chlorine-containing waste suitable for pretreatment [ Ning Huayu ] researches on chloride ion elution and cement solidification in waste incineration fly ash, cement 2018 and (12) 9-12 ].

The water washing process is divided into two schemes of potassium chloride resource recovery and non-recovery. The non-recovery scheme of potassium chloride resource is to wash the solid waste containing chlorine fly ash and other waste with water for reuse. The chlorine-containing component entering the liquid phase enters the municipal sewage treatment system along with the discharged circulating water, and the chlorine component is not recovered.

The potassium chloride resource recovery scheme is to wash the chlorine-containing fly ash with water, recycle the washing water, and recover the industrial salt prepared by concentrating and crystallizing the chlorine-containing compound.

3425 Zxft 3425 [ 3562 Zxft 3562, 4324 Zxft 4324, 3245 Zxft 3245, etc. ] the washing dechlorination and cement solidification technology of municipal refuse incineration fly ash, science technology and engineering, 2019, 19 (35): 395-401 ] the dechlorination rate reaches 74.64% when the liquid-solid ratio is 20. The technology has large investment and relatively high disposal cost.

The bypass air-release treatment is to directly discharge part of waste gas (the temperature is above 900 ℃) in a kiln tail smoke chamber (generally called as bypass air-release), and discharge potassium, sodium, chlorine and the like which are circularly enriched in the smoke gas from a production system by taking dust out of the discharged waste gas, thereby realizing the operation of a cement kiln system and the stability of the quality of cement products. For smoke dust particles led out by bypass air release, if the chlorine content is high, potassium chloride products are mostly extracted by water washing and acid washing at present, and residues obtained after potassium chloride is extracted are dried and then mixed into cement clinker, or mixed with cement raw materials and then enter a cement production unit.

Mu Luying [ Mu Luying ] cement kiln co-processing solid waste bypass air release technology shallow analysis, chinese cement 2019, (4): 105-107 ] field pilot plant is carried out to investigate the separation and collection effect of chlorine-containing components at different flue gas temperatures. The bypass air-bleeding high-temperature flue gas (about 1000-1100 ℃) is cooled to 450-500 ℃ by an shock cooling machine, enters a primary cyclone cylinder to primarily remove particles, then is doped with cold air at a flue, enters a comprehensive reactor after the temperature of the flue gas is reduced to below 250 ℃, and is sent to the inlet of a kiln tail dust remover through a draught fan after dust and other harmful substances are removed. In the pilot test, the chloride ions in the bypass flue gas are not condensed on the dust at 450 ℃, and a large amount of chloride ions are attached to the dust after the temperature of the flue gas is reduced to 250 ℃. The content of chloride ions in the smoke dust particles collected by the primary cyclone cylinder is only 1.87%, the chlorine content in the smoke dust particles removed by the comprehensive processor is 19.58%,79.94% of the smoke dust particles are captured in the primary cyclone dust collector, and 20.06% of the smoke dust particles are captured in the comprehensive processor. Although the primary cyclone dust collector has higher collection efficiency on smoke dust particles, the collection efficiency on chlorine-containing components is higher and reaches 27.64 percent.

Part of the flue gas is led out from the tail of the cement rotary kiln, so that an enrichment cycle chain of chlorine element in a cement production line is broken, and a local open loop is formed. Cooling, dedusting and purifying the extracted flue gas, and trapping the chloride in a gaseous state along with the smoke dust. The collected smoke dust particles are mixed into cement clinker and are ground into a cement product.

No matter the chlorine extraction and separation scheme is a pretreatment chlorine extraction and separation scheme or a bypass air-release chlorine extraction and separation scheme, the chlorine-containing solid powder needs to be subjected to wet treatment of water washing or acid washing to separate out chlorides, and the technical schemes have the following defects:

1) And (4) processing the process route length. The chlorine-containing components in the fly ash chlorine-containing waste can be dissolved in the liquid phase and separated from the insoluble components in the fly ash by adopting a wet method, but the chlorine-containing compounds dissolved in the liquid phase need to be crystallized and separated, and units such as chloride crystallization, dehydration, drying and the like need to be matched.

2) The wet process has the risk of secondary pollution of waste liquid. Although the water washing solution or the acid washing solution in the wet treatment process is recycled, the concentrated solution is crystallized to extract chlorine-containing compounds such as potassium chloride, fly ash or smoke particles contain a small amount of organic chlorine compounds besides inorganic chlorine-containing compounds, the components are enriched along with the circulation of the circulating solution, the crystallization effect is influenced in the process of concentrating and crystallizing the inorganic chlorine-containing compounds, and a small amount of the components are mixed into crystals of the chlorine-containing compounds. In order to improve the separation efficiency of the inorganic chlorine-containing compounds, the circulating concentrated solution must be partially discharged and independently disposed.

3) Large investment, high operation cost and high energy consumption. The treatment process comprises operation units such as washing/pickling, crystallization separation, drying and the like, particularly, solid-phase residues after wet chlorine extraction can enter a cement production unit only after being dried, and the whole treatment process has the advantages of multiple operation units, high energy consumption, large investment and high operation cost.

4) The chlorine content in the cement clinker is relatively high. The technical scheme of the process for blending the smoke dust particles with low chlorine content back to the cement clinker can relieve ring formation and blockage in a kiln in the production process of the rotary cement kiln, and can not cause the standard exceeding of harmful components in the cement. However, after all, the addition of the components into the cement clinker leads to the increase of the content of chlorine components in the cement, and meanwhile, a large amount of smoke particles still exist in the process of not participating in the sintering reaction of the cement clinker, and the participation of the components has certain influence on the quality of cement products. And also results in the waste of potassium chloride resources.

In order to solve the problems of high separation cost of chlorine-containing components, large risk of secondary environmental pollution and the like in the synergistic treatment of chlorine-containing waste by a rotary cement kiln and improve the efficiency of the synergistic treatment of the chlorine-containing waste by the rotary cement kiln, a new technology which has no secondary pollution, low operation cost and less investment needs to be developed urgently.

Disclosure of Invention

The invention aims to solve the technical problems and provides a dry method recovery process for chlorine components in synergistic treatment of chlorine-containing solid wastes based on a cement kiln, which has the advantages of simple process, low investment cost and operation cost, environmental friendliness, energy conservation and consumption reduction and can effectively recover potassium chloride products.

The technical scheme includes that solid waste containing chlorine components enters a cement production line, the chlorine components are gasified and enter flue gas under the high-temperature environment in a rotary kiln, part of the flue gas is led out from a kiln head flue gas hood of the rotary kiln, the led-out part of the flue gas is sent into a cooling tower after being dedusted by a dry method to directly exchange heat with potassium chloride powder materials for cooling, the chlorine components in the flue gas are condensed and enter the potassium chloride powder materials, the flue gas after heat exchange is discharged from the top of the cooling tower, and the potassium chloride powder materials after heat exchange are discharged from the bottom of the cooling tower.

The dry dedusting comprises the steps of conveying part of the flue gas from the kiln head flue gas hood into a temperature control combustion chamber to adjust the temperature to be more than 1150 ℃, then conveying the flue gas into a high-temperature deduster to remove dust, and then conveying the flue gas into a cooling tower.

Introducing coal gas or natural gas, oxygen-enriched air or oxygen and straw powder materials into the temperature-controlled combustion chamber for combustion so as to adjust the temperature of the flue gas to be more than 1150 ℃.

The adding amount of the straw powder material is determined according to the molar ratio of chlorine to potassium in the co-processing solid waste, and the spraying amount is controlled to be 50-100 kg/ten thousand Nm ³ Flue gas.

And the smoke dust particles separated by the high-temperature dust remover are sent into the rotary kiln.

The high-temperature dust remover is a multi-tube cyclone dust remover or a ceramic filter film dust remover.

And after the potassium chloride powder material discharged from the bottom of the cooling tower is sent into a heat exchanger for indirect heat exchange and temperature reduction, part of the potassium chloride powder material is discharged as a potassium chloride-containing product, and the rest of the potassium chloride powder material is returned into the cooling tower for heat exchange with flue gas.

After the heat-exchanged flue gas discharged from the top of the cooling tower is dedusted by a bag-type dust collector, part of the flue gas is led out to be used as carrier gas to convey potassium chloride powder materials discharged from a heat exchanger into a cooling tower to exchange heat with the flue gas, and the rest of the flue gas enters a pulverizer to heat cement raw materials; the powder discharged from the bottom of the bag-type dust collector is a potassium chloride-containing product.

In view of the problems in the background art, the inventor makes the following improvements:

the traditional process of wet treatment on the smoke led out by the bypass air release is abandoned, and the common understanding that the chloride is led into the liquid phase through water washing is overcome. Analysis shows that the flue gas temperature of the rotary kiln is high, almost all the chloride in the flue gas is gas phase, dry-method high-temperature dust removal is directly carried out under the condition, the dust is separated out in one step, the chloride content in the dust is extremely low, the dust can be directly returned to the rotary kiln in a thermal state (the waste heat of the dust is favorably recycled), the chlorine content in the cement is effectively reduced, and the aim of removing chlorine of the system is fulfilled; the dedusted chlorine-containing flue gas is not washed by a wet method, but is sent into a cooling tower to be directly subjected to heat exchange and temperature reduction by using a circularly cooled potassium chloride powder material, and simultaneously, a potassium chloride component in the flue gas is condensed and enters the potassium chloride powder material to realize the recovery of potassium chloride; the flue gas after heat exchange discharged from the top of the cooling tower contains potassium chloride dust, a potassium chloride product (containing more than 60 mass percent of potassium chloride) can be separated and recovered through the bag-type dust remover, and the separated low-temperature flue gas can enter a pulverizer to heat a cement raw material to further recover waste heat.

Potassium chloride powder materials at the bottom of the tower enter a heat exchanger to indirectly exchange heat with cooling water to recover heat energy, the temperature is reduced to below 150 ℃, the potassium chloride powder materials are sent to a cooling tower in a circulating mode, the potassium chloride powder materials are used as heat exchange media to directly exchange heat and condense high-temperature flue gas, potassium chloride in the flue gas is continuously condensed in the potassium chloride powder materials, and the recovery rate and the content of potassium chloride products are effectively improved.

Furthermore, in order to reduce the condensation of potassium chloride into dust in the dry dedusting process, the temperature of the flue gas before entering the high-temperature deduster is preferably increased to more than 1150 ℃, so that a temperature control combustion chamber is additionally arranged in front of the high-temperature deduster, and when the temperature of the flue gas is lower than 1150 ℃, the flue gas is heated and warmed through the temperature control combustion chamber. Further, straw powder materials are preferably sprayed into the temperature-controlled combustion chamber, and the straws contain abundant potassium and sodium, and the molar ratio of potassium, sodium and chlorine reaches 3, so that the potassium is abundant, thereby being beneficial to reacting with chlorine elements in smoke dust to generate potassium chloride (Bao Wenzhong, zhang Lei and Zhang Fubin. Cement kiln bypass air release technology and waste heat utilization introduction: cement technology, 2013. (6): 96-99 (chlorine brought into kiln gas in the volatilization process of chlorine components is more likely to react with potassium to generate potassium chloride, and the excessive chlorine can form sodium chloride with sodium generally only after the potassium chloride is formed). At the same time, at temperatureIn the environment of 600 ℃, alkali metal chloride in the straw biomass starts to be gasified, and the gasification is basically finished at 900 ℃. Therefore, chlorine elements in the particles in the flue gas can be promoted to be fully gasified to generate potassium chloride steam. The straw powder material can be rice, wheat and other straws, the spraying amount is determined according to the mol ratio of chlorine to potassium in the co-processing solid waste, and the spraying amount is generally controlled to be 50-100 kg/ten thousand Nm ³ The flue gas aims to improve the separation rate of chlorine elements in the smoke dust and reduce the content of chlorine in cement clinker, so that excessive potassium resources in the straws are wasted, and insufficient chlorine is not beneficial to chlorination of chlorine in the smoke dust.

The cooling tower can use the cooling tower that has the direct heat transfer of current realization, and preferred slag is from clearing up the cooling tower, including last tower body, middle part ring carrier, lower tower body, hot powder storehouse, the flue gas is advanced, is exported, and the powder spouts the mouth, and thick powder material export, wherein, go up tower body, lower tower body and the axial of hot powder storehouse inner chamber link up, it is uncovered for upper end and lower extreme to go up the tower body, the middle part exists at least that one section diameter reduces 10-20% small tower footpath section and lower part diameter and enlarges 10-20% calabash tripe form structure, the tower body comprises outer barrel and center tube down, outer barrel is located the center tube periphery, and is coaxial with the center tube.

The slag self-cleaning cooling tower device creatively arranges a central tube in the cooling tower and skillfully forms a circular seam structure for gas flowing. The structure has the functions of adhesion resistance and slag self-cleaning. High-temperature gas tangentially enters the inner circular seam of the cooling tower from the gas inlet of the cooling tower, is further dedusted under the action of centrifugal force, and the central pipe is heated to make the temperature of the central pipe be higher than the melting point or even the boiling point of the potassium chloride component. The central tube is made of heat-resistant steel or ceramic material with good heat conductivity, the outer side of the central tube is in long-term contact with the entering high-temperature gas, the temperature is close to or even reaches the high-temperature flue gas temperature, the inner side of the central tube is in contact with the fluidized potassium chloride powder material for cooling, and part of the potassium chloride powder material is heated by the high temperature of the inner wall to be molten and adhered to the inner wall; in addition, gaseous potassium chloride components in the high-temperature flue gas are cooled by the powder material and are reduced to the temperature below the boiling point, condensed into fog drops which are adsorbed by the powder material and possibly adhered to the wall surface when contacting and colliding with the inner wall of the central tube. And (3) the adhesive layer is thickened along with the increase of the wall surface adhesive surface, the thermal resistance is increased, the temperature of the inner wall surface of the central pipe is increased, and when the temperature is higher than the boiling point of the slag component, the slag layer is melted and falls off.

On the other hand, the cooling tower structure is skillfully designed into a variable-diameter gourd-shaped structure, and at least 1 gourd-shaped neck is arranged, so that the structure has the following technical effects on the fluidization and mixing of the gas-solid mixture:

a, the gas-solid mixture can pass through a dense phase region, a dilute phase region, a dense phase region and a dilute phase region for many times through the change of the inner diameter, which is beneficial to the sufficient fluidization of biomass, increases the turbulent motion effect of airflow in a fluidized bed and strengthens the gas-solid mixing.

And b, the sidewall effect and the channeling existing in the operation process of the fluidized bed are completely avoided through the change of the inner diameter.

And c, the powder material grading efficiency is high. The change of the tower diameter can cause the gas phase flow velocity to change correspondingly, the gas phase flow velocity is large in the inner diameter reducing area, the powder material with smaller particle size is brought into the previous inner diameter expanding area, and the powder material with larger particle size falls into the next inner diameter expanding area. As the temperature in the tower is gradually reduced from bottom to top, the gas phase flow velocity is gradually reduced from bottom to top, the powder material with larger particle size falling to the next area is intercepted in the area and further contacted with the gas-solid mixture under the fluidization action of the larger gas phase flow velocity when passing through the area with the reduced inner diameter, molten fog drops are adhered, the particle size is further increased, and when the particle size is larger than the critical sedimentation particle size, the powder material passes through the small tower diameter section and enters the thermal state powder bin.

The heat exchanger can use the heat exchanger of the existing various indirect heat exchanges, is preferably a powder material spiral heat exchanger, and comprises a powder inlet, a spiral upper shell, spiral blades, a heat exchange tube array, an exhaust port, an upper end orifice plate, a lower end orifice plate, a central water inlet pipe, a central water outlet pipe, a water inlet end seal head, a water outlet end seal head, a spiral lower shell and a powder outlet, wherein the heat exchange tube array penetrates through pipe holes in the spiral blades along the axial direction of the spiral blades, is respectively connected and fixed on the upper end orifice plate and the lower end orifice plate, and is respectively and sequentially connected with the water inlet end seal head, the central water inlet pipe, the water outlet end seal head and the central water outlet pipe along the axial two ends of the spiral blades through the upper end orifice plate and the lower end orifice plate to form a coaxial rotating body.

The powder material spiral heat exchanger disclosed by the invention is compact in structure, high in space utilization rate and high in heat exchange efficiency. When the powder material is cooled or heated, the powder material can be filled into the cavity of the cylinder to be passed through, so that the whole heat exchange tube array is submerged, and the heat exchange area is large.

Has the advantages that:

the invention has simple process, small occupied area and low investment cost and operation cost, and compared with the traditional wet method chloride removal process, the invention saves the investment by more than 60 percent, the occupied area by more than 60 percent and the operation cost by more than 50 percent; the dry dedusting process does not consume water resources in the whole process, is environment-friendly, does not have secondary pollution, saves energy and reduces consumption; the recovery rate of the potassium chloride is high and can reach more than 80 percent; the cement quality is improved, high-content potassium chloride products can be recycled, the flue gas treatment cost is reduced, and the exhaust emission is reduced.

Drawings

FIG. 1 is a process flow diagram of example 1 of the present invention.

FIG. 2 is a process flow diagram of example 2 of the present invention.

Wherein, 1, a feed hopper; 2. a main induced draft fan; 3. a cyclone dust collector; 4. a decomposing furnace; 5. a bypass air inducing port; 6. a rotary kiln; 7. a bag-type dust collector; 8-1, a ceramic filter dust remover; 8-2, a multi-pipe cyclone dust collector; 9. a temperature controlled combustion chamber; 10. a powder nozzle; 11. a burner; 12. a kiln head sealing cover; A. a slag self-cleaning cooling tower; B. powder material spiral heat exchanger.

FIG. 3 is a schematic structural view of a slag self-cleaning cooling tower A according to the present invention.

FIG. 4 isbase:Sub>A sectional view taken along line A-A.

Fig. 5 is a front view of the middle annular seat A2.

Fig. 6 is a top view of the middle annular seat A2.

Fig. 7 is a front view of the ring-shaped saddle-type bunker A6.

Fig. 8 is a top view of the annular saddle-shaped silo A6.

Fig. 9 is a left side view of the annular saddle-shaped silo A6.

Wherein: wherein: a1, an upper tower body; a1-1, a gas outlet; a1-2, an outlet end tower diameter contraction section; a1-3, a large tower diameter section; a1-4, a small tower diameter section; a1-5, calabash belly section; a1-6, calabash belly extrados; a2, a middle annular support; a2-1, a calabash belly inner cambered surface; a2-2, an inner arc surface of the horn mouth; 2-3, heat-resistant concrete; a2-4, a concrete protective steel plate; a2-5, a support pad; a3, a powder spraying port; a3-1, a lower layer powder spraying port; a3-2, a middle layer powder spraying port; a3-3, an upper layer powder spraying port; a3-4, a dust return port; a4, a lower tower body; a4-1, an outer cylinder body; a4-2, a central tube; a4-3, a bell mouth outer arc surface; a5, an air inlet; a5-1, a short gas inlet pipe; a6, an annular saddle-shaped stock bin; a6-1, an annular gap-shaped feed inlet; a6-2, saddle peak; a6-3, saddle-shaped inclined plane; a6-4, a dust discharging pipe; a6-5, saddle bottom; a6-6, a dust unloading valve; a7, a thermal state powder bin; a8, a powder feeding pipe; a9, powder unloading valve.

Fig. 10 is a schematic structural diagram of a powder material spiral heat exchanger B of the present invention.

FIG. 11 is a top view of the powder material spiral heat exchanger of the present invention.

Fig. 12 isbase:Sub>A sectional viewbase:Sub>A-base:Sub>A of fig. 12.

Fig. 13 is a partially enlarged view of (1) in fig. 10.

Fig. 14 is a partially enlarged view of fig. 10 (2).

Fig. 15 is a schematic structural view of the helical blade B3.

Wherein: b1, a powder inlet; 2. a spiral upper housing; b2-1, an upper end sealing plate of the upper shell; b2-2, a lower end sealing plate of the upper shell; b2-3, an upper shell flange; b2-4, a perspective hole; b3, helical blades; b4, heat exchange tubes; b5, an exhaust port; b6-1, and a purge gas inlet pipe at the upper end; b6-2, a lower end purge gas inlet pipe; b6-3, blowing a scavenging gas at the upper end to spray out the circular seam; b6-4, blowing the scavenging gas at the lower end to spray out the circular seam; b6-5, a lower end purge gas lead-out port; b7-1, an upper end orifice plate; b7-2, a lower end orifice plate; b8-1, a central water inlet pipe; b8-2, a central water outlet pipe; b9-1, an upper end bearing seat; b9-2, a lower end bearing seat; b9-3, a bearing; b10-1, sealing an upper end; b10, concrete foundation; b11-1, sealing a water inlet end; b11-2, sealing a water outlet end; b12, a spiral lower shell; b12-1, an upper end sealing plate of the lower shell; b12-2, a lower end sealing plate of the lower shell; b12-3, a lower shell flange; b13, powder outlet; b14, a sealing ring; b15, an annular conductive baffle disc; b16, a gas guide ring; b17, an annular permanent magnet baffle disc; b18, annular cushion blocks; b19, a junction tube; b20, emptying.

Detailed Description

The invention is further explained below with reference to the drawings in which:

referring to fig. 1 and 2, the system for the dry separation of chlorine-containing components based on the synergistic disposal of solid waste in a cement kiln comprises a rotary kiln 6, wherein a kiln head flue gas hood 12 of the rotary kiln 6 is provided with a bypass induced draft opening 5, the bypass induced draft opening 5 is connected with a flue gas inlet in the middle of a cooling tower (in this embodiment, a slag self-cleaning cooling tower a) through a dry dust removal device, and the middle of the cooling tower is provided with a powder injection port; the powder exit linkage heat exchanger (be powder material spiral heat exchanger B in this embodiment) at the cooling tower bottom, the powder export of heat exchanger is connected the powder mouth of spouting of outer pipeline and cooling tower respectively. The flue gas outlet at the top of the cooling tower is respectively connected with the powder outlet pipeline of the heat exchanger and the gas inlet of the pulverizer through a bag-type dust remover 7

The dry dedusting device comprises a temperature control combustion chamber 9 and a high-temperature deduster which are sequentially connected, and a dust outlet at the bottom of the high-temperature deduster is connected with the rotary kiln 6. The lower part of the temperature control combustion chamber 9 is provided with a combustor 11, and a plurality of powder nozzles 10 are arranged above the combustor 11 and along the circumferential direction of the combustion chamber.

In the present invention, the high temperature dust collector may be a ceramic filter dust collector 8-1 (see FIG. 1) or a multi-cyclone dust collector 8-2 (see FIG. 2).

The process comprises the following steps:

the solid waste containing the chlorine component enters a cement production line (including but not limited to a feed hopper 1, a multi-stage cyclone dust collector 3, a decomposing furnace 4 and a rotary kiln 6 which are sequentially connected and are shown in the figure), the chlorine component is gasified and enters flue gas in the rotary kiln 6 under the high-temperature environment, and partial flue gas is led out from a kiln head flue gas hood 12 of the rotary kiln 6 through a bypass air inlet 5 (the led-out flue gas accounts for 4 of the total flue gas of the kiln head)8 percent by volume), the extracted part of the flue gas is firstly sent into a temperature control combustion chamber 9 to adjust the temperature to be more than 1150 ℃ (preferably 1150 to 1200 ℃), then sent into a high temperature dust remover to remove dust and then sent into a cooling tower. Introducing coal gas or natural gas, oxygen-enriched air or oxygen into the temperature-controlled combustion chamber 9 for combustion, and simultaneously spraying straw powder materials through a powder nozzle 10 above the combustor 11 for combustion so as to promote chlorine elements in the particles in the flue gas to be fully gasified to generate potassium chloride steam. The adding amount of the straw powder material is determined according to the molar ratio of chlorine to potassium in the co-processing solid waste, and the preferable spraying amount is controlled to be 50-100 kg/ten thousand Nm ³ Flue gas. And the smoke dust particles separated by the high-temperature dust remover are sent into the rotary kiln 6.

The high-temperature dust remover is a multi-cyclone dust remover 8-2 or a ceramic filter dust remover 8-1, more than 80% of particles can be removed by the multi-cyclone dust remover 8-2, and more than 95% of particles can be removed by the ceramic filter dust remover 8-1.

The flue gas is dedusted by a dry method, then is sent into a slag self-cleaning cooling tower A to directly exchange heat with cooled potassium chloride powder materials (the temperature is lower than 150 ℃) sprayed into the tower for cooling, chlorine-containing components in the flue gas are condensed and enter the potassium chloride powder materials, the flue gas with the heat exchange temperature lower than 250 ℃ is discharged from the top of the tower, the potassium chloride powder materials with the heat exchange temperature raised to 350-450 ℃ are discharged from the bottom of the tower and then are sent into a powder material spiral heat exchanger B to indirectly exchange heat and cool to below 150 ℃, part of the potassium chloride-containing products are discharged as potassium chloride-containing products, and the rest of the flue gas returns into the slag self-cleaning cooling tower A to exchange heat with the flue gas.

After the heat-exchanged flue gas discharged from the top of the cooling tower is dedusted by a bag-type dust collector 7, part of the flue gas is led out to be used as carrier gas to convey part of potassium chloride powder material discharged from a powder material spiral heat exchanger to a slag self-cleaning cooling tower A for heat exchange with the flue gas, and the rest part of the flue gas is sent to a pulverizer to heat cement raw materials; the powder discharged from the bottom of the bag-type dust collector 7 is a potassium chloride-containing product.

The structure of the cooling tower a for self-cleaning of slag in this embodiment is described in detail in the prior application No. 202010667032.2 entitled "high temperature soot powder fluidization cooling tower based on self-cleaning of slag". Referring to fig. 3-9, the technical scheme includes an upper tower body A1, a middle annular support A2, a lower tower body A4, a thermal state powder bin A7, a gas inlet A5 (a flue gas inlet), a gas outlet A1-1 (a flue gas outlet), a powder spraying inlet A3, a powder discharging pipe A8 (a coarse powder material outlet), inner cavities of the upper tower body A1, the lower tower body A4 and the thermal state powder bin A7 are axially communicated, the upper tower body A1 is open at the upper end and the lower end, at least one small tower diameter section A1-4 with a diameter reduced by 10-20% and a calabash belly section A1-5 with a diameter expanded by 10-20% are arranged in the middle of the upper tower body A1, the lower tower body A4 is composed of an outer cylinder body A4-1 and a central pipe A4-2, and the outer cylinder body A4-1 is positioned at the periphery of the central pipe A4-2 and is coaxial with the central pipe A4-2.

The upper end of an outer cylinder A4-1 of the lower tower body A42 is connected and sealed with the lower edge of the middle annular support A2, and the central tube A4-2, the middle annular support A2 and the outer cylinder A4-1 form an annular seam space structure with a closed upper end and an open lower end.

The upper tower body A1 is placed on the middle annular support A2, and the outer arc surface A1-6 of the gourd belly of the upper tower body A1 is connected with the inner arc surface A2-1 of the gourd belly of the middle annular support A2 and is contacted, fixed and sealed through the arc surfaces.

The lower part of the central pipe A4-2 is cylindrical, the upper end port of the central pipe A4-2 is an outwards-expanded horn mouth-shaped structural body, the central pipe A4-2 is fixedly suspended on the middle annular support A2 through a horn mouth, and the outer arc surface A4-3 of the horn mouth is connected with the inner arc surface A2-2 of the horn mouth of the middle annular support and is fixed and sealed through arc surface contact.

The calabash tripe intrados A2-1 of middle part ring carrier A2 be located with middle part ring carrier A2's horn mouth intrados A2-2's top evenly sets up a plurality of middle level powder mouth of spouting A3-3 along circumference between two cambered surfaces, the directional calabash tripe center of direction is spouted into to middle level powder mouth of spouting A3-3's powder, middle part ring carrier A2 supports through a plurality of stands.

And an air inlet 5 is tangentially arranged on the side wall of the upper end of the outer cylinder A4-1. The lower end opening of an outer barrel A4-1 of the lower tower body A4 is connected with the upper end opening of an outer ring of the annular saddle-shaped stock bin A6, a thermal state powder bin A7 is arranged in an inner ring of the annular saddle-shaped stock bin A6, the thermal state powder bin A7 is embedded in the inner ring of the annular saddle-shaped stock bin A6, the upper end opening of the thermal state powder bin A7 is flush with the upper end opening of the annular saddle-shaped stock bin, and the diameter of the upper end opening of the thermal state powder bin A7 is equal to that of the central pipe.

An annular gap-shaped feed inlet A6-1 of the annular saddle-shaped feed bin A6 corresponds to the annular gap of the lower tower body A4 and is positioned right below the annular gap of the lower tower body A4, and the width of the annular gap is equivalent to that of the annular gap.

The inclination angle of the saddle surface of the annular saddle-shaped storage bin A6 is larger than the repose angle of dust, and the bottoms of the two saddles are connected with a dust discharging pipe A6-4 and a dust discharging valve A6-6. The inclination angle of the calabash tripe is larger than the angle of repose of the powder material.

The annular saddle-shaped bunker A6 is characterized in that a plurality of lower-layer powder spraying ports A3-1 are uniformly formed in the inner annular wall of the annular saddle-shaped bunker A6 along the circumferential direction, the powder spraying direction of the lower-layer powder spraying ports A3-1 points to the center of a lower port of a central pipe, a plurality of upper-layer powder spraying ports A3-3 are uniformly formed in the small tower diameter section of the upper tower body A1 along the circumferential direction, and the powder spraying direction of the upper-layer powder spraying ports A3-3 is horizontal or inclined downwards.

The working principle is as follows:

the flue gas is introduced into the tower from the gas inlet A5 of the outer cylinder A4-1, the gas generates rotational flow to carry out cyclone dust removal under the control of an inner annular seam structure of the tower, and the removed dust enters the annular saddle-shaped bin A6. The dedusted high-temperature gas enters the central pipe A4-2 from the lower port of the central pipe A4-2, and is mixed and fluidized with the powder material sprayed from the lower layer powder spraying port A3-1 to form a gas-solid mixture.

In the central tube A4-2, the gas-solid mixture rises along with the airflow and carries out high-efficiency heat exchange, the temperature of the powder material rises, the temperature of the flue gas is reduced, and the powder material and the inner wall of the central tube 4-2 carry out heat exchange.

The central tube A4-2 is made of heat-resistant steel or ceramic material with good heat conductivity, the outer side of the central tube is in long-term contact with the entering converter flue gas, the temperature is close to or even reaches the electric furnace flue gas temperature, the inner side of the central tube 4-2 is in contact with fluidized powder materials for cooling, and part of the materials are heated by the high temperature of the inner wall to be molten and adhered to the inner wall of the central tube A4-2; in addition, under the cooling action of the sprayed powder material, the temperature of potassium chloride in the converter flue gas is reduced to be lower than the boiling point temperature, the potassium chloride is condensed and adsorbed by the powder material, and the potassium chloride is possibly adhered to the wall surface when contacting and colliding with the inner wall of the central pipe A4-2. The adhesive layer is thickened and the thermal resistance is increased along with the increase of the wall surface adhesive surface, the temperature of the inner wall surface of the central tube A4-2 is increased, and when the temperature is higher than the boiling point of the adhesive layer, the adhesive layer on the inner wall is melted and falls off.

After the converter flue gas exchanges heat with the powder material sprayed from the lower layer powder spraying inlet A3-1 in the central pipe A4-2, the flue gas is cooled. The flue gas after primary cooling continues to rise, when the flue gas passes through the upper port of the central pipe A4-2, the flue gas is mixed with the powder material sprayed from the middle layer powder spraying port A3-2, and enters the calabash belly section A1-5 of the upper tower body A1, meanwhile, the powder material is sprayed from the upper layer powder spraying port A3-3, and is settled to the lower edge of the calabash belly section A1-5, and is in countercurrent contact with the rising gas-solid mixture and mixed. As the sectional area of the calabash belly section A1-5 is suddenly increased, the flow velocity of the gas-solid mixture from the central pipe A4-2 is suddenly reduced, violent turbulence is generated, a rotational flow is formed, the rotational flow is vigorously mixed with the settled powder material, rapid heat exchange is carried out, and the temperature of the flue gas is further reduced.

In the calabash belly section A1-5, due to the obstruction of the powder material layer settled in the central area, and simultaneously, due to the sudden increase of the sectional area of the calabash belly section A1-5, airflow is diffused and flows to the periphery, so that the further mixing of the gas-solid mixture in the calabash belly section A1-5 is intensified, and the retention time is prolonged.

The powder material and the gas-solid mixture exchange heat and adsorb partial condensed fog drops, the particle size is further increased, the fog drops are settled in a thermal state powder bin 7 after the particle size exceeds the critical particle size, and the fog drops are discharged through a powder discharging pipe A8 and a powder ash discharging valve A9 and enter waste heat recovery equipment.

The temperature of the gas-solid mixture after being fully cooled by the calabash section A1-5 is reduced to below 200 ℃, the gas-solid mixture leaves the calabash section A1-5, passes through the small tower diameter section A1-4, and is subjected to step-by-step gas-solid heat exchange in the large tower diameter section A1-3, the temperature of the flue gas is reduced to below 150 ℃, and the cooled converter flue gas carries powder materials to pass through the outlet end tower diameter contraction section A1-2 and be discharged from a gas outlet A1-1.

The structure of the spiral heat exchanger B for powder material in this embodiment is described in detail in application No. 202010667081.6, a prior application entitled "a spiral heat exchanger for powder material". Referring to fig. 10-15, the technical scheme includes a powder inlet B1, a spiral upper shell B2, a spiral blade B3, a heat exchange tube array B4, an exhaust port B5, an upper end orifice plate B7-1, a lower end orifice plate A7-2, a central water inlet tube B8-1, a central water outlet tube B8-2, a water inlet end seal B11-1, a water outlet end seal B11-2, a spiral lower shell B12, and a powder outlet B13, wherein the heat exchange tube array B4 axially penetrates through a tube hole on the spiral blade B3 along the spiral blade B3, is respectively connected and fixed to the upper end orifice plate B7-1 and the lower end orifice plate A7-2, and is respectively connected with the water inlet end seal B11-1, the central water inlet tube B8-1, the water outlet end seal B11-2, and the central water outlet tube B8-2 along the spiral blade axis B3 through the upper end orifice plate B7-1 and the lower end orifice plate A7-2 in sequence to form a coaxial rotator.

The rotating body is positioned in a closed cylindrical cavity formed by the spiral upper shell B2 and the spiral lower shell B12, and the central water inlet pipe B8-1 and the central water outlet pipe B8-2 extend out of the cylindrical body from two ends of the cylindrical cavity; the spiral upper shell B2 consists of an upper shell upper end seal plate B2-1, an upper shell lower end seal plate B2-2, an upper shell flange B2-3 and a perspective hole B2-4; the spiral lower shell B12 consists of a lower shell upper end sealing plate B12-1, a lower shell lower end sealing plate B12-2 and a lower shell flange B12-3.

The rotating body and the cylinder are coaxial and are arranged on a concrete foundation in an inclination of 1.5-5%, the cylinder is fixedly arranged on the concrete foundation, the rotating body is fixedly arranged on an upper end bearing seat B9-1 and a lower end bearing seat B9-2 through a central water inlet pipe B8-1 and a central water outlet pipe B8-2 extending out of the cylinder and bearings arranged on the central water inlet pipe B8-1 and the central water outlet pipe B8-2, and the upper end bearing seat B9-1 and the lower end bearing seat B9-2 are fixedly arranged on the concrete foundation.

The heat exchange tube array B4 is composed of a plurality of metal tubes which are arranged in parallel, two ends of each metal tube are firmly and hermetically connected to an upper end pore plate B7-1 and a lower end pore plate B7-2 respectively, the upper end pore plate B7-1 is firmly and hermetically connected with the water inlet end seal head B11-1, the lower end pore plate B7-2 is firmly and hermetically connected with the water outlet end seal head B11-2, the convex tops of the water inlet end seal head B11-1 and the water outlet end seal head B11-2 are provided with central holes, and the central water inlet tube B8-1 and the central water outlet tube B8-2 are firmly and hermetically connected to the centers of the water inlet end seal head and the water outlet end seal head respectively; the water inlet end sealing head and the central water inlet pipe B8-1 can be installed together in a welding mode or directly cast into a whole, and the central water inlet pipe B8-1 can also be connected through a short pipe flange at a convex top which is cast into a whole with the water inlet end sealing head B11-1; the water outlet end sealing head B11-2 and the central water outlet pipe B8-2 can be installed together in a welding mode or directly cast into a whole, and the central water outlet pipe B8-2 can also be connected through a short pipe flange at the convex top which is cast into a whole with the water outlet end sealing head B11-2.

An annular cushion block B18, an annular permanent magnet baffle disc B17 and an annular conductive baffle disc B15 are sequentially arranged between the outside of the convex top of the water outlet end sealing head B11-2 and the cylindrical lower end sealing plate, the annular permanent magnet baffle disc B17 is embedded in an air guide ring B16, and the air guide ring B16, the annular cushion block B18 and the annular permanent magnet baffle disc B17 are sleeved on the central water outlet pipe B8-2 and are tightly fixed on the water outlet end sealing head B11-2; the annular conductive baffle disc B17 is sleeved on the central water outlet pipe B8-2 and is tightly fixed on the cylindrical lower end sealing plate; the air guide ring B16, the annular cushion block B18, the annular permanent magnet baffle disc B17 and the annular conductive baffle disc B15 are coaxial with the central water outlet pipe B8-2.

A lower end scavenging gas inlet pipe B6-2 is arranged on the lower end sealing plate B2-2 of the upper shell, and the lower end scavenging gas inlet pipe B6-2 is sequentially communicated with a lower end scavenging gas spraying circular seam B6-4 and a lower end scavenging gas leading-out port B6-5; an upper end scavenging gas inlet pipe B6-1 is arranged on the upper end sealing plate B2-1 of the upper shell, and the upper end scavenging gas inlet pipe B6-1 is communicated with an upper end scavenging gas spraying circular seam B6-3.

The annular cushion block B18 is made of a heat insulating material with high compressive strength, and the air guide ring B16 is made of a heat insulating material.

And a wiring tube is arranged on the lower end sealing plate B12-2 of the lower shell, and the electrified lead of the annular conductive baffle disc B15 is led out of the cylinder body through the wiring tube B19.

The spiral upper shell B2 and the spiral lower shell B12 are positioned and fixedly connected through a flange.

The heat exchange tube array B4 penetrating through the spiral blade tube hole is fixedly connected with the spiral blade B3 through intermittent welding.

An annular cushion block B18, an annular permanent magnet baffle disc B17 and an annular conductive baffle disc B15 which are arranged in sequence can be sleeved on the central water outlet pipe B8-2 extending out of the outer side of the cylinder.

The working principle is as follows:

in the device, a water inlet end socket B11-1, a central water inlet pipe B8-1, a water outlet end socket B11-2 and a central water outlet pipe B8-2 are respectively and sequentially connected with an upper end orifice plate B7-1 and a lower end orifice plate B7-2 along the two axial ends of a helical blade 3 to form the coaxial transportation of a rotator, so that the fly ash is driven to obliquely and upwards flow to a powder outlet B13 from a closed cylindrical cavity surrounded by a helical upper shell B2 and a helical lower shell B12, the fly ash and cooling water flowing reversely in a heat exchange tube B4 exchange heat through the tube wall, the temperature of the fly ash is reduced, the temperature of the cooling water is increased, when the fly ash is discharged from the powder outlet B13, the temperature is reduced to be below 100 ℃, and the cooling water is heated to generate steam and is led out from the central water outlet pipe B8-2. The rotating body is driven to rotate by a transmission device arranged at the outer end of the central water inlet pipe B8-1.

A starting step:

(1) Before the rotating body is started, the annular conductive baffle disc B15 is electrified through an electrified lead of the annular conductive baffle disc B15 led out from the conductive baffle disc wiring tube B19, and the rotating body moves upwards in an inclined mode under the action of electromagnetic force between the annular permanent magnet baffle disc B17 and the annular conductive baffle disc B15;

(2) Opening a water inlet valve (not shown in the figure), injecting cooling water into the rotating body, wherein the cooling water enters a water inlet end socket B11-1 through a central water inlet pipe B8-1, passes through an upper end pore plate B7-1, enters a heat exchange tube array B4, passes through a lower end pore plate B7-2, enters a water outlet end socket B11-2 and converges into a central water outlet pipe B8-2;

(3) After the heat exchange tube array 4 is filled with water, starting the rotating body to drive the upper end orifice plate B7-1, the lower end orifice plate B7-2, the helical blade B3, the heat exchange tube array B4 and the like to rotate together, discharging hot powder into the inner cavity of the cylinder body through the powder inlet B1, enabling the powder in the inner cavity of the cylinder body to move upwards in an inclined manner under the rotating and conveying effects of the helical blade B3 to reversely exchange heat with cooling water in the heat exchange tube array B4, and discharging cooled fly ash from the powder outlet B13;

(4) The discharge amount of the powder and the flow rate of the cooling water are adjusted to control the temperature of the fly ash discharged from the powder outlet B13.

Claims

1. A dry method recovery process for chlorine components based on cooperative disposal of chlorine-containing solid wastes by a cement kiln comprises the steps that the solid wastes containing the chlorine components enter a cement production line, the chlorine-containing components are gasified and enter flue gas under the high-temperature environment in the rotary kiln, and part of the flue gas is led out from a kiln head flue gas hood of the rotary kiln;

2. The dry-method recovery process for chlorine components in the chlorine-containing solid waste based on the cement kiln co-processing of the claim 1, wherein the dry-method dust removal comprises the steps of feeding part of the flue gas from the kiln head flue gas hood into a temperature-controlled combustion chamber to adjust the temperature to be more than 1150 ℃, feeding the flue gas into a high-temperature dust remover to remove dust, and feeding the flue gas into a cooling tower.

3. The dry-method recovery process for chlorine components in synergic treatment of chlorine-containing solid wastes based on the cement kiln as claimed in claim 2, characterized in that coal gas or natural gas, oxygen-enriched air or oxygen, and straw powder materials are introduced into the temperature-controlled combustion chamber for combustion to adjust the temperature of flue gas to more than 1150 ℃.

4. The dry recovery process for chlorine components in the co-processing chlorine-containing solid waste based on the cement kiln as claimed in claim 3, wherein the addition amount of the straw powder material depends on the molar ratio of chlorine to potassium in the co-processing solid waste, and the injection amount is controlled to be 50-100 kg/ten thousand Nm ³ Flue gas.

5. The dry recovery process for chlorine components from chlorine-containing solid wastes based on cement kiln co-processing as claimed in claim 2, wherein the dust particles separated by the high temperature dust remover are sent into the rotary kiln.

6. The dry recovery process for chlorine components based on cement kiln co-processing of chlorine-containing solid waste according to claim 2, characterized in that the high temperature dust collector is a multi-tube cyclone dust collector or a ceramic filter dust collector.

7. The dry recovery process for chlorine components from the co-disposal chlorine-containing solid waste based on the cement kiln as claimed in any one of claims 1 to 6, wherein the flue gas after heat exchange discharged from the top of the cooling tower is dedusted by a bag-type dust collector, a part of the flue gas is extracted as a carrier gas to convey potassium chloride powder material discharged from a heat exchanger to a cooling tower for heat exchange with the flue gas, and the rest of the flue gas is sent to a pulverizer to heat cement raw materials; the powder discharged from the bottom of the bag-type dust collector is a potassium chloride-containing product.

8. The dry recovery process for chlorine components from chlorine-containing solid wastes by cement kiln co-processing according to any one of claims 1 to 6, wherein the cooling tower is a slag self-cleaning cooling tower, and comprises an upper tower body, a middle annular support, a lower tower body, a hot powder bin, a flue gas inlet, a flue gas outlet, a powder spray inlet, and a coarse powder material outlet, wherein the inner cavities of the upper tower body, the lower tower body and the hot powder bin are axially communicated, the upper tower body is open at the upper end and the lower end, the middle part of the upper tower body is provided with at least one small tower diameter section with a diameter reduced by 10 to 20 percent, and the lower part of the upper tower body is provided with a calabash-shaped structure with a diameter enlarged by 10 to 20 percent, the lower tower body is composed of an outer cylinder and a central tube, and the outer cylinder is positioned at the periphery of the central tube and is coaxial with the central tube.

9. The dry recovery process for chlorine components based on cooperative disposal of chlorine-containing solid wastes in a cement kiln as claimed in claim 1, wherein the heat exchanger is a powder material spiral heat exchanger, and comprises a powder inlet, a spiral upper shell, spiral blades, a heat exchange tube array, an exhaust port, an upper end orifice plate, a lower end orifice plate, a central water inlet pipe, a central water outlet pipe, a water inlet end seal head, a water outlet end seal head, a spiral lower shell and a powder outlet, wherein the heat exchange tube array axially penetrates through the pipe holes on the spiral blades along the spiral blades, is respectively fixedly connected to the upper end orifice plate and the lower end orifice plate, and is respectively and sequentially connected to the water inlet end seal head, the central water inlet pipe, the water outlet end seal head and the central water outlet pipe along the axial two ends of the spiral blades through the upper end orifice plate and the lower end orifice plate to form a coaxial rotator.