CN113975919A

CN113975919A - Dry-method chlorine component recovery process based on cooperative disposal of chlorine-containing solid wastes by cement kiln

Info

Publication number: CN113975919A
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: 2022-01-28
Anticipated expiration: 2041-09-30
Also published as: CN113975919B

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 from an urban waste incineration power plant, is a typical hazardous waste containing chlorine components (potassium chloride and sodium chloride), has the chlorine content of 10 percent, and is even higher [ Zhang Lei, Zhang Yunze. sodium and potassium salt separation application in a fly ash cement kiln cooperative 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 cement kiln co-processing solid wastes (Lizhong, Hantao, Xiaoshengdou, and the like), the research of cement kiln bypass ventilation technology, 2012.6:29-32, the high content of potassium, sodium, chlorine and sulfur in raw materials and fuels can bring serious consequences to the stable operation of a cement production line system, the prominent phenomenon is that the skinning and blocking phenomena are easy to occur at the positions of a kiln tail smoke chamber, a blanking slope, a necking and a cone of a lowest stage cyclone cylinder, and the stable and normal operation of a firing system can be influenced in serious cases. That is, in cement production lines, the area at 800-.

Theoretically, KCl, NaCl, CaCl₂The 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, the cement raw material is a mixture of a plurality of inorganic salt compounds, so the cement raw material is theoreticallyAnalytically, these salt mixtures form eutectic point components and the vaporization temperature is also reduced. According to the analysis of the skinning blockage phenomenon in the actual production, the boiling point of the mixed salt containing the chlorine component is 800-900 ℃. Therefore, during the cement production process, the chlorine-containing component is gasified at high temperature, condensed at 900 ℃ and enters the high-temperature zone in the cement production unit again along with the cement raw material, thereby forming the cyclic enrichment of the chlorine-containing component in the cement production unit.

Lei Rui Qing et al [ Lei Rui Qing, etc.. NaCl-CaCl₂-BaCl₂And NaCl-KCl-BaCl₂Calculation 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 salt₂In 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.

The Bawenzhong and the like analyze the circulating mechanism of chlorine in the cement production process [ Bawenzhong, and the like, the bypass air release technology of the cement kiln and the brief introduction of waste heat utilization, the 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 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 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 below 1450 ℃ in the kiln, so that it is re-volatilized shortly 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 for co-processing chlorine-containing wastes 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 and the like are adopted in the pretreatment scheme of the chlorine-containing waste suitable for pretreatment [ Ninghuayu, research on chloride ion elution and cement solidification in waste incineration fly ash, cement 2018, (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 with water for reuse. The chlorine-containing component entering the liquid phase enters the urban 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.

Zhangzhiku, etc. (Zhang Zhikun, Wangjing, Lihaotan, etc. washing dechlorination of municipal refuse incineration fly ash and cement solidification technology, scientific technology and engineering, 2019, 19(35): 395-. 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 the 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 again.

Mulocolline cement kiln synergetic treatment solid waste bypass air release technology shallow analysis Chinese cement 2019, (4): 105-. Cooling the bypass air-bleeding high-temperature flue gas (about 1000-1100 ℃) to 450-500 ℃ by an shock cooling machine, entering a primary cyclone cylinder to primarily remove particles, then doping cold air at a flue, reducing the temperature of the flue gas to below 250 ℃, entering a comprehensive reactor, removing dust and other harmful substances, and then sending the flue gas into an inlet of a kiln tail dust remover by an induced draft fan. 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 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 and dust particles, the collection efficiency on chlorine-containing components is also 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 wet method can dissolve the chlorine-containing components in the fly ash chlorine-containing waste into the liquid phase and separate the chlorine-containing components from the insoluble components in the fly ash, but the chlorine-containing compounds dissolved in the liquid phase need to be crystallized and separated out and need to be matched with units such as chloride crystallization, dehydration, drying and the like.

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 disposed of separately.

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 Nm³Flue 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 vent 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 due to the fact that straws contain abundant potassium and sodium, the molar ratio of potassium, sodium and chlorine reaches 3, potassium is abundant, and therefore the straw powder materials and the straws can be favorably reacted with chlorine elements in smoke dust to generate potassium chloride (the advantages of envelopment faithfulness, Zhangiumben and Zhang Fubin). Meanwhile, in the environment with the temperature of 600 ℃, alkali metal chloride in the straw biomass starts to be gasified, and the gasification is basically finished at the temperature of 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 mole ratio of chlorine to potassium in the co-disposal solid waste, and the spraying amount is generally controlled to be 50-100 kg/ten thousand Nm³The flue gas aims to improve the separation rate of chlorine element in the smoke dust and reduce the content of chlorine in the cement clinker, so that the waste of potassium resource in the straw can be caused too much, and the chlorination of chlorine in the smoke dust is not facilitated too little.

The cooling tower can use the existing cooling tower capable of realizing direct heat exchange, preferably is a slag self-cleaning cooling tower and comprises an upper tower body, a middle annular support, a lower tower body, a thermal state powder bin, a flue gas inlet and outlet, a powder spraying port and a coarse powder material outlet, wherein the inner cavities of the upper tower body, the lower tower body and the thermal state 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 at least provided with a small tower diameter section with the diameter reduced by 10-20% and a calabash belly structure with the diameter expanded by 10-20%, the lower tower body is composed of an outer barrel body and a central tube, the outer barrel body is positioned at the periphery of the central tube and is coaxial with the central 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, further removes dust under the action of centrifugal force, and heats the central pipe at the same time, so that the temperature of the central pipe is above the melting point and 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 temperature of high-temperature flue gas, the inner side of the central tube is in contact with fluidized potassium chloride powder materials for cooling, and part of the potassium chloride powder materials are heated by the inner wall at high temperature 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 is provided with at least 1 gourd neck, so that the structure has the following technical effects on the fluidization 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 diagram of a slag self-cleaning cooling tower A according to the present invention.

FIG. 4 is a sectional view taken along line A-A.

Fig. 5 is a sectional view B-B.

Fig. 6 is a front view of the middle annular seat a 2.

Fig. 7 is a top view of the middle annular seat a 2.

Fig. 8 is a front view of the annular saddle-shaped silo a 6.

Fig. 9 is a top view of the annular saddle-shaped silo a 6.

Fig. 10 is a left side view of the annular saddle-shaped silo a 6.

Fig. 11 is a cross-sectional view C-C of fig. 9.

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, calabash belly intrados; a2-2, an inner arc surface of the horn mouth; a2-3, heat-resistant concrete; a2-4, concrete protective steel plates; a2-5, a support pad; a3, powder spraying port; a3-1, lower layer powder spraying port; a3-2, a middle layer powder spraying port; a3-3, an upper powder spraying port; a3-4, a dust return port; a4, a lower tower body; a4-1, an outer cylinder; a4-2, central tube; a4-3, a bell mouth outer arc surface; a5, air inlet; a5-1, short air inlet pipe; a5, an annular saddle-shaped stock bin; a5-1, an annular gap-shaped feed inlet; a5-2, saddlepeak; a5-3, saddle type inclined plane; a5-4, a dust discharge pipe; a5-5, saddle bottom; a5-6, dust unloading valve; a7, a thermal state powder bin; a8, powder blanking pipe; a9, powder unloading valve.

Fig. 12 is a schematic structural diagram of a powder material spiral heat exchanger B of the present invention.

FIG. 13 is a top view of the powder material spiral heat exchanger of the present invention.

Fig. 14 is a sectional view a-a of fig. 12.

FIG. 15 is a partially enlarged view of (i).

FIG. 16 is a partially enlarged view.

Fig. 17 is a structural schematic view of a helical blade B3.

Wherein: b1, powder inlet; 2. a spiral upper housing; b2-1, an upper end sealing plate of the upper shell; b2-2, an upper shell lower end closing plate; b2-3, an upper shell flange; b2-4, a perspective hole; b3, helical blades; b4, heat exchange tubes; b5, an exhaust port; b6-1, an upper end purge gas inlet pipe; b6-2, lower end purge gas inlet pipe; b6-3, blowing the 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, and an upper end socket; b10, concrete foundation; b11-1, a water inlet end sealing head; b11-2, sealing the 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, annular conductive baffle disc; b16, air guide ring; b17, an annular permanent magnet blocking disc; b18, an annular cushion block; b19, a junction tube; b20, and a vent.

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 the 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; and a powder outlet at the bottom of the cooling tower is connected with a heat exchanger (a powder material spiral heat exchanger B in the embodiment), and a powder outlet of the heat exchanger is respectively connected with an external discharge pipeline and a powder spraying inlet of the cooling tower. The flue gas outlet at the top of the cooling tower is respectively connected with a powder outlet pipeline of the heat exchanger and a gas inlet of the pulverizer through a bag-type dust collector 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 method comprises the steps that solid waste containing chlorine components enters a cement production line (including but not limited to a feed hopper 1, a multi-stage cyclone dust collector 3, a decomposition furnace 4 and a rotary kiln 6 which are sequentially connected and shown in the figure), the chlorine components are gasified and enter flue gas in the rotary kiln 6 under a high-temperature environment, part of the 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 4-8% of the total flue gas of the kiln head by volume percent), the led-out 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 1150-1200 ℃), and then is sent into a high-temperature dust collector to be dedusted and then sent into a cooling tower. Coal gas or natural gas, oxygen-enriched air or oxygen are introduced into the temperature-controlled combustion chamber 9 for combustion, and meanwhile, straw powder materials are sprayed into the temperature-controlled combustion chamber through a powder nozzle 10 above a combustor 11 for combustion, so that chlorine elements in particulate matters in the flue gas are promoted 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-treatment solid waste, and the preferable spraying amount is controlled to be 50-100 kg/ten thousand Nm³Flue 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-pipe cyclone dust remover 8-2 or a ceramic filter dust remover 8-1, more than 80% of particles can be removed by the multi-pipe 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 and then 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-plus-one temperature of 450 ℃ are discharged from the bottom of the tower and then sent into a powder material spiral heat exchanger B to indirectly exchange heat and cool the temperature 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. 3-11, the technical scheme includes an upper tower body a1, a middle annular support a2, a lower tower body A4, a hot powder bin a7, a gas inlet A5 (a flue gas inlet), a gas outlet a1-1 (a flue gas outlet), a powder spraying port A3, a powder discharging pipe A8 (a coarse powder material outlet), wherein inner cavities of the upper tower body a1, the lower tower body A4 and the hot powder bin a7 are axially communicated, the upper tower body a1 is open at the upper end and the lower end, a small tower diameter section a1-4 with a diameter reduced by 10-20% and a calabash belly section a1-5 with a diameter enlarged by 10-20% are arranged in the middle, 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 located 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 a circular 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 calabash belly outer arc surface A1-6 of the upper tower body A1 is connected with the calabash belly inner arc surface A2-1 of the middle annular support A2 and is contacted, fixed and sealed through arc surfaces.

The lower part of the central pipe A4-2 is cylindrical, the upper port of the central pipe A4-2 is an outward-expanding bell-mouth-shaped structural body, the central pipe A4-2 is fixedly suspended on the middle annular support A2 through a bell mouth, and the bell-mouth extrados surface A4-3 is connected with the bell-mouth intrados surface A2-2 of the middle annular support and is fixed and sealed through cambered surface contact.

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

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 cylinder A4-1 of the lower tower body A4 is connected with the upper end opening of an outer ring of an annular saddle-shaped storage bin A6, a thermal state powder bin A7 is arranged in an inner ring of the annular saddle-shaped storage bin A6, a thermal state powder bin A7 is embedded in the inner ring of the annular saddle-shaped storage 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 storage 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 bunker 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 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 greater 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 arranged on 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 arranged on 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 the annular seam structure in the tower, and the removed dust enters the annular saddle-shaped stock 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 A4-2 is in long-term contact with the entering converter flue gas, the temperature is close to or even reaches the temperature of the flue gas of the electric furnace, the inner side of the central tube 4-2 is in contact with fluidized powder material for cooling, and part of the material is 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.

The flue gas of the converter in the central pipe A4-2 exchanges heat with the powder material sprayed from the lower powder spraying port A3-1, and then 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 sprayed powder material at the middle layer powder spraying port A3-2 and enters the calabash belly section A1-5 of the upper tower body A1, and 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 to be 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 violently 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 blockage 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 diffuses and flows to the periphery, 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 the 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 fully cooled by the calabash segment A1-5 is reduced to below 200 ℃, the gas-solid mixture leaves the calabash segment A1-5, passes through the small tower diameter segment A1-4, and is subjected to step-by-step gas-solid heat exchange in the large tower diameter segment 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 segment A1-2 and is discharged from a gas outlet A1-1.

The structure of the powder material spiral heat exchanger B in this embodiment is described in detail in the prior application entitled "a powder material spiral heat exchanger" under application number 202010667081.6. Referring to fig. 12-17, the technical scheme includes that the powder heat exchanger comprises 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 head B11-1, a water outlet end head B11-2, a spiral lower shell B12 and a powder outlet B13, the heat exchange tube array B4 axially penetrates through tube holes 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 to both ends along a spiral blade axis B3 through the upper end orifice plate B7-1 and the lower end orifice plate A7-2 to the water inlet end head B11-1, the central water inlet tube B8-1 and the water outlet end head B11-2 and the central water outlet tube B8-2, constitute a coaxial rotating body.

The rotary body is positioned in a closed cylinder 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 cylinder from two ends of the cylinder 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 is composed 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 is coaxial with the cylinder and is arranged on a concrete foundation at 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 which extend 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 nest B4 is composed of a plurality of metal tubes arranged in parallel, two ends of each metal tube are firmly and hermetically connected to an upper end orifice plate B7-1 and a lower end orifice plate B7-2 respectively, the upper end orifice plate B7-1 is firmly and hermetically connected with the water inlet end seal head B11-1, the lower end orifice 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 head B11-2 and the lower end sealing plate of the cylinder, 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 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 lower end sealing plate of the cylinder; the air guide ring B16, the annular cushion block B18, the annular permanent magnet baffle disk B17 and the annular conductive baffle disk B15 are coaxial with the central water outlet pipe B8-2.

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

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 B19 wiring tube.

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 holes is fixedly connected with the spiral blades B3 through intermittent welding.

An annular cushion block B18, an annular permanent magnet baffle disc B17 and an annular conductive baffle disc B15 are sequentially arranged and can be sleeved on a 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 two ends of an upper end orifice plate B7-1 and a lower end orifice plate B7-2 along the axial direction of a helical blade 3 to form the transportation of a coaxial rotating body, 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, and the fly ash and cooling water flowing in the reverse direction in a heat exchange tube array 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 below 100 ℃, and steam generated after the cooling water is heated 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 an annular conductive baffle disc B15 led out from a conductive baffle disc wire connecting tube B19, and the rotating body moves upwards in an inclined mode under the action of electromagnetic force between an annular permanent magnet baffle disc B17 and an annular conductive baffle disc B15;

(2) opening a water inlet valve (not shown in the figure), injecting cooling water into the rotating body, enabling the cooling water to enter a water inlet end socket B11-1 through a central water inlet pipe B8-1, to cross an upper end pore plate B7-1, to enter a heat exchange tube nest B4, to cross a lower end pore plate B7-2, to enter a water outlet end socket B11-2, and to converge into a central water outlet pipe B8-2;

(3) after the heat exchange tube nest 4 is filled with water, the rotating body is started to drive the upper end orifice plate B7-1, the lower end orifice plate B7-2, the helical blade B3, the heat exchange tube nest B4 and the like to rotate together, meanwhile, hot powder discharged through the powder inlet B1 enters the inner cavity of the cylinder body, under the rotating and conveying actions of the helical blade B3, the powder in the inner cavity of the cylinder body moves upwards in an inclined mode and reversely exchanges heat with cooling water in the heat exchange tube nest B4, and cooled fly ash is discharged from the powder outlet B13;

(4) the discharge amount of the powder and the flow rate of the cooling water were 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 of enabling the solid wastes containing the chlorine components to enter a cement production line, enabling the chlorine-containing components to be gasified and enter flue gas in a high-temperature environment in the rotary kiln, and leading out part of the flue gas 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 of chlorine components from chlorine-containing solid waste based on cement kiln co-processing as claimed in claim 2, wherein coal gas or natural gas, oxygen-enriched air or oxygen and straw powder are introduced into the temperature-controlled combustion chamber to combust so as to adjust the temperature of flue gas to more than 1150 ℃.

4. The dry-method chlorine component recovery process based on cement kiln co-processing chlorine-containing solid waste, as claimed in claim 3, wherein the amount of the straw-like powder material added depends on the mole ratio of chlorine to potassium in the co-processing solid waste, and the amount of the sprayed powder material is controlled to be 50-100 kg/ten thousand Nm³Flue 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 of chlorine-containing solid wastes with the cement kiln as claimed in any one of claims 1 to 6, wherein the potassium chloride powder material discharged from the bottom of the cooling tower is sent to a heat exchanger for indirect heat exchange and temperature reduction, and then part of the potassium chloride powder material is discharged as a potassium chloride-containing product, and the rest part of the potassium chloride powder material is returned to the cooling tower for heat exchange with flue gas.

8. 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.

9. 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.

10. The dry recovery process for chlorine components based on cooperative disposal of chlorine-containing solid wastes in a cement kiln as recited in claim 7, 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.