CN112179156A

CN112179156A - Bypass air-bleeding energy-saving emission-reduction utilization system and process for cooperatively treating waste in cement kiln

Info

Publication number: CN112179156A
Application number: CN202011069226.9A
Authority: CN
Inventors: 金万金
Original assignee: Dalian 95 Hi Tech New Energy Development Co ltd
Current assignee: Dalian 95 Hi Tech New Energy Development Co ltd
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2021-01-05

Abstract

The invention relates to a bypass air-bleeding energy-saving emission-reducing utilization system and process for cooperatively treating wastes by a cement kiln, which are mainly applied to cement production enterprises. The device comprises a kiln tail smoke chamber, a primary quenching device, a primary quenching fan, an SNCR denitration device, a secondary air mixing fan, a kiln tail bag dust collection device, a kiln tail SP waste heat boiler, an air preheater, an air blower, a dust collector, a tail exhaust fan, a kiln tail chimney and a hot air using device. Wherein kiln tail smoke chamber, one-level rapid cooling device, second grade mix wind device, air heater, dust collector, tail exhaust fan and kiln tail chimney pass through the flue and connect gradually in proper order, and wherein one-level rapid cooling device adopts air cooling, and the second grade mixes wind device and adopts kiln tail SP exhaust-heat boiler export flue gas as cooling gas to cool off, in order to reach the environmental protection requirement, has still set up SNCR denitrification facility in the system. The system can quickly and effectively reduce the temperature of the bypass air-bleeding flue gas, avoid blockage in the pipeline, effectively utilize the heat in the flue gas, reduce the energy consumption of the system and meet the requirement of environmental protection.

Description

Bypass air-bleeding energy-saving emission-reduction utilization system and process for cooperatively treating waste in cement kiln

Technical Field

The invention relates to an energy-saving and emission-reducing system and process, in particular to a bypass air-bleeding energy-saving and emission-reducing utilization system and process for cooperatively treating wastes by a cement kiln, which are mainly used for cement production enterprises.

Background

When the content of harmful elements in the cement raw combustion material is higher or when the cement kiln is used for cooperatively treating wastes, the contents of chlorine, sulfur, alkali and other harmful substances entering the kiln system exceed the standard, the harmful substances are circularly enriched in the system, and particularly the concentrations of alkali, chlorine and sulfur compounds in a kiln tail smoke chamber reach the highest values. This can cause the phenomena of skinning and blocking of the smoke chamber, the decomposing furnace and part of the cyclone, which can affect the normal operation of the system, and even cause the reduction and stop of the production of the system in serious cases. In order to eliminate adverse effects of elements such as chlorine, sulfur, alkali and the like on cement production and improve the adaptability of cement kiln to cooperatively treat wastes, a bypass air release technology is mainly adopted to solve the problems at present.

The bypass air release technology is a measure for opening an air release opening at a position with higher concentration of R +, Cl-and S in a tail smoke chamber of a cement kiln to release part of high-temperature kiln gas and dust so as to reduce the content of R +, Cl-and S and reduce the phenomena of skinning and blocking. Wherein, the high-temperature kiln gas is discharged into the atmosphere after being cooled and dedusted; the collected dust is homogenized through batching and warehousing or discarded.

The current bypass ventilation technology mainly has the following problems in the implementation process. Firstly, high-temperature flue gas in a kiln tail smoke chamber contains dust, and a large amount of alkaline compounds are also arranged on the surface of the dust, so that the dust has high viscosity, and the problem of kiln dust adhesion and blockage exists in the air intake process; secondly, the extracted high-temperature flue gas is discharged into the atmosphere after being cooled and dedusted, the heat of the high-temperature flue gas is not recovered, and the heat consumption of the cement kiln is increased; thirdly, the air quantity of the system can be greatly increased only by adopting the air mixing mode to cool the high-temperature flue gas, so that the selection of the dust collector and the tail exhaust fan is increased, and the manufacturing cost of the system is higher; fourthly, the operation temperature of the rotary kiln reaches more than 1600 ℃, a large amount of NOx which mainly takes a thermal type and a fuel type is generated while various toxic and harmful substances are solidified and decomposed, the concentration of the NOx in smoke of a smoke chamber can even reach more than 1500mg/Nm3, and the emission of a chimney is directly arranged to be difficult to meet the requirement of environmental protection emission;

disclosure of Invention

In view of the problems in the prior art, the invention provides a cement kiln bypass air-bleeding exhaust waste gas energy-saving and emission-reduction utilization system and process, which can comprehensively utilize heat in bypass air-bleeding high-temperature flue gas, reduce energy consumption of cement production, save system cost and meet increasingly strict environmental protection emission requirements.

The technical scheme adopted by the invention is as follows: a cement kiln bypass air-bleeding exhaust waste gas energy-saving emission-reduction utilization system and a process thereof comprise a kiln tail smoke chamber, a primary quenching device, a primary quenching fan, an SNCR denitration device, a secondary air mixing fan, a kiln tail bag dust collection device, a kiln tail SP waste heat boiler, an air preheater, an air blower, a dust collector, a tail exhaust fan, a kiln tail chimney and a hot air using device; the kiln tail smoke chamber, the primary quenching device, the SNCR denitration device, the secondary air mixing device, the air preheater, the dust collector, the tail exhaust fan and the kiln tail chimney are sequentially connected through a flue, a cooling air inlet of the primary quenching device is connected with an outlet of the primary quenching fan, and an inlet of the primary quenching fan is connected with air; a cooling air inlet of the secondary air mixing device is connected with an outlet of a secondary air mixing fan, an inlet of the secondary air mixing fan is connected with a dust-collected outlet of a kiln tail bag, the dust-collected outlet of the kiln tail bag is simultaneously connected with a kiln tail chimney, and the dust-collected inlet of the kiln tail bag is connected with an outlet of a kiln tail SP waste heat boiler; the air inlet of the air preheater is connected with the outlet of the air blower, and the air outlet of the air preheater is connected with the inlet of the hot air using device.

The hot air using device is a tertiary air pipe or a kiln tail SP waste heat boiler or a kiln head AQC waste heat boiler.

The flue gas outlet of the primary quenching device, the flue gas outlet of the secondary air mixing device, the hot air outlet of the air preheater and the hot flue gas outlet of the air preheater are respectively provided with a thermocouple.

The primary quenching device is connected with a primary quenching fan and is provided with a valve for controlling air quantity; the secondary air mixing device and the secondary air mixing fan are connected with an air pipe, and a valve for controlling air quantity is arranged on the air pipe; and a valve for controlling the air quantity is arranged on the air inlet of the air preheater and the air blower connecting air pipe.

The first-stage quenching device adopts a volute structure or a sleeve structure.

The first-stage quenching device of the volute structure is cylindrical, two ends of the cylinder are connected with a flue gas pipeline, and a cooling air inlet is arranged at the tangential position of the side surface of the cylinder.

The primary quenching device of the sleeve structure is composed of two concentric sleeves inside and outside, and the end part of each sleeve is provided with an end plate, so that a closed cavity is formed between the two sleeves; wherein, interior sleeve pipe both ends are connected with flue gas pipeline, offer a plurality of holes on the interior sleeve pipe circumference wall, and the outer tube pipe wall is equipped with the cooling air entry.

The temperature of the smoke outlet of the first-stage quenching device is 500-1100 ℃, the temperature of the smoke outlet of the second-stage air mixing device is 300-950 ℃, the temperature of the hot air outlet of the air preheater is 200-800 ℃, and the temperature of the hot smoke outlet of the air preheater is 100-360 ℃.

The working process of the invention is as follows: an air discharge opening is formed in the enrichment part of the tail smoke chamber R +, Cl-and S-of the cement kiln, part of high-temperature smoke with high R +, Cl-and S contents and 1200 ℃ is extracted through a bypass air intake flue, the high-temperature smoke enters a primary quenching device through a flue and is mixed and cooled with cold air from the outlet of a primary quenching fan, and in order to prevent viscous dust in the smoke from being blocked due to adhesion on the inner wall surface of the primary quenching device, the primary quenching device adopts a volute structure or a sleeve structure. The first-stage quenching device of the volute structure is simple in structure, cooling air enters from the tangential direction and moves along the wall surface due to the inertia effect, so that hot flue gas is wrapped in the cooling air, and dust is prevented from being bonded and blocked on the wall surface; the one-level quenching device of the sleeve structure has the advantages that cooling air enters from small holes in the wall surface of the inner sleeve to generate certain air pressure, dust is prevented from being bonded and blocked on the wall surface, and meanwhile, the cooling air can be effectively mixed with smoke to reduce the temperature. The temperature of the flue gas cooled by the primary quenching device is reduced to 500-1100 ℃, and the cooling air quantity entering the primary quenching device is adjusted by adjusting the opening degree of a valve on an air pipe connected with the primary quenching device and a primary quenching fan, so that the temperature of the cooled flue gas is optimally 850-1050 ℃. The flue gas then enters an SNCR denitration device to remove NOx in the flue gas. The denitrated flue gas enters a secondary air mixing device, is fully mixed with the cooling flue gas at the outlet of a secondary air mixing fan and is cooled to 300-950 ℃, and the cooling air quantity entering the secondary air mixing device is adjusted by adjusting the opening degree of a valve on an air pipe connecting the secondary air mixing device and the secondary air mixing fan, so that the temperature of the cooled flue gas is optimal to 650 ℃. The inlet of the secondary air mixing fan is connected with the outlet of the kiln tail bag for collecting dust, the outlet of the kiln tail bag for collecting dust is connected with a kiln tail chimney, and the inlet of the kiln tail bag for collecting dust is connected with the outlet of the kiln tail SP waste heat boiler. The hot flue gas cooled by the secondary air mixing device enters an air preheater, and exchanges heat with cold air input by an air blower through a heat exchange surface of the air preheater, the temperature of the air is increased to 200-800 ℃ after heat exchange, and the temperature of the flue gas after heat exchange is reduced to 100-360 ℃. The opening degree of a valve on an air inlet of the air preheater and an air pipe connected with a blower is adjusted, and the amount of cold air input into the air preheater is adjusted, so that the outlet temperature of hot air after heat exchange of the air preheater is optimally 450-550 ℃, and the temperature of outlet flue gas after heat exchange of the air preheater is optimally 160 ℃. Then the flue gas enters a dust collector for dust removal. And the flue gas after dust removal enters a kiln tail chimney through a tail exhaust fan to be discharged. The hot air at the outlet of the air preheater can be sent to a tertiary air pipe and enters the decomposing furnace as combustion-supporting air. Or can be sent to the inlet of the kiln tail SP waste heat boiler to increase the steam production of the kiln tail SP waste heat boiler. The steam can also be sent to the inlet of the kiln head AQC waste heat boiler, so that the steam production of the kiln head AQC boiler is increased.

The invention has the following beneficial effects:

1. the first-level quenching device adopts a volute structure or a sleeve structure, a cooling isolation layer is formed between hot flue gas and the wall surface of the device, the problem that dust in bypass air-bleeding flue gas is easy to adhere and block on the wall surface can be effectively solved, and the good and stable operation of the system is ensured.

2. And the waste heat in the bypass air-bleed waste gas is fully utilized through an air preheater. Hot air generated by the air preheater can be sent into a tertiary air pipe and then enters the decomposing furnace to be used as combustion-supporting air, so that the tertiary air quantity extracted by the kiln head grate cooler is correspondingly reduced, the zero pressure surface of the grate cooler moves forwards, the increase of the heat quantity of flue gas entering the kiln head boiler is influenced, and the steam production quantity of the kiln head boiler is correspondingly increased; hot air generated by the air preheater can be sent to an inlet of the kiln tail SP boiler, so that the steam production of the kiln tail SP boiler can be increased; hot air generated by the air preheater can also be sent to the inlet of the kiln head AQC boiler, so that the steam production of the kiln head AQC boiler can be increased; by the method, the power generated by the waste heat of the cement kiln can be effectively improved by about 5-30%.

3. Partial flue gas rich in harmful components such as potassium, sodium, chlorine and sulfur is discharged from the kiln tail smoke chamber through the system, and then a part of tertiary air is supplemented through the air preheater, so that the oxygen content of the flue gas in the decomposing furnace is improved, and the effects of improving the combustion condition of the kiln system, improving the coal combustion efficiency and reducing the coal consumption are achieved.

4. The high-temperature and high-alkali flue gas is cooled by the air preheater, so that the cooling air volume doped in the system can be effectively reduced, the capacities of the dust collector and the tail exhaust fan are greatly reduced, and the total cost of the bypass air discharge comprehensive utilization system is reduced.

5. The tail smoke chamber of the cement kiln is an enrichment part with the maximum concentration of NOx, an air discharge port is arranged at the enrichment part to discharge part of high-temperature kiln gas, and the temperature of the part of high-temperature kiln gas is reduced to 850-1050 ℃ after the part of high-temperature kiln gas is mixed with air by a primary quenching device. At this temperature, adopt SNCR denitration technology, the chemical reaction that takes place that aqueous ammonia and high concentration NOx can be more abundant, and the denitration effect is better, the improvement of phase-change like this system denitration efficiency. The ammonia water that the device used compares and to reduce before the bypass is let out the wind, under the circumstances that satisfies the environmental protection requirement, can practice thrift the running cost of system about 10%.

6. The secondary air mixing device adopts flue gas obtained after dust collection and dust removal of a kiln tail SP waste heat boiler outlet through a kiln tail bag, and the oxygen content in the flue gas is low to form a low-temperature oxygen-deficient reducing atmosphere, so that the NOx content in the flue gas after air mixing is greatly reduced, and compared with the secondary air mixing method adopting air, the NOx concentration in the flue gas discharged by the system can be reduced from about 400mg/m3 to about 320mg/m3, so that the increasingly severe environment-friendly emission requirements are met.

7. After harmful components such as potassium, sodium, chlorine, sulfur and the like in the system are discharged by the method, the alkali content in the system is reduced, so that the requirement of production enterprises for producing low-alkali cement is met.

Drawings

FIG. 1 is a process system diagram I of the present invention

FIG. 2 is a schematic diagram II of a process system of the present invention

FIG. 3 is a schematic view of a process system of the present invention III

FIG. 4 is a schematic structural view of a spiral case type primary quenching device

FIG. 5 is a schematic structural view of a bushing type primary quenching device

Labeled as: kiln tail smoke chamber 1, primary quenching device 2, primary quenching fan 3, secondary air mixing device 4, secondary air mixing fan 5, air preheater 6, air blower 7, dust collector 8, tail exhaust fan 9, kiln tail chimney 10, tertiary air pipe 11, kiln tail SP boiler 12, kiln head AQC boiler 13, SNCR denitrification facility 14, kiln tail bag dust collection 15, cooling air inlet 6, outer sleeve 17, inner sleeve 18, flue gas inlet 19, flue gas outlet 20

Detailed Description

The following is further described with reference to the accompanying drawings.

The text is first briefly explained as follows:

SNCR: selective Non-Catalytic Reduction, a denitration technique, i.e. Selective Non-Catalytic Reduction;

AQC: air Quenching Cooler, grate Cooler;

SP: suspension Preheater, Suspension Preheater.

As shown in fig. 1, a kiln tail smoke chamber, a primary quenching device, an SNCR denitration device, a secondary air mixing device, an air preheater, a dust collector, a tail exhaust fan and a kiln tail chimney are sequentially connected through a flue, a cooling air inlet of the primary quenching device is connected with an outlet of the primary quenching fan, and an inlet of the primary quenching fan is connected with air; a cooling air inlet of the secondary air mixing device is connected with an outlet of a secondary air mixing fan, an inlet of the secondary air mixing fan is connected with a dust-collected outlet of a kiln tail bag, the dust-collected outlet of the kiln tail bag is simultaneously connected with a kiln tail chimney, and the dust-collected inlet of the kiln tail bag is connected with an outlet of a kiln tail SP waste heat boiler; the air inlet of the air preheater is connected with the outlet of the air blower, and the air outlet of the air preheater is connected with the tertiary air pipe.

In the system, thermocouples are respectively arranged at a smoke outlet of the primary quenching device, a smoke outlet of the secondary air mixing device, a hot air outlet of the air preheater and a hot smoke outlet of the air preheater and are used for detecting the temperature of a medium.

A valve for controlling air quantity is arranged on a connecting air pipe of the primary quenching device and the primary quenching fan; the second-stage air mixing device is connected with the second-stage air mixing fan, and an air pipe is provided with a valve for controlling air quantity; the air inlet of the air preheater and the air blower are connected with an air pipe, valves for controlling air quantity are arranged on the air pipe, and the flow of the medium is adjusted by controlling the opening of the valves.

The specific working process is as follows: an air discharge port is arranged at the enrichment part of the tail smoke chamber R +, Cl-and S of the cement kiln, part of high-temperature smoke with high R +, Cl-and S contents and the temperature of 1200 ℃ is extracted through a bypass air intake flue, and the high-temperature smoke enters a primary quenching device through a flue and is mixed and cooled with cold air from the outlet of a primary quenching fan. The temperature of the flue gas cooled by the primary quenching device is reduced to 500-1100 ℃, and the cooling air quantity entering the primary quenching device is adjusted by adjusting the opening degree of a valve on an air pipe connected with the primary quenching device and a primary quenching fan, so that the temperature of the cooled flue gas is optimally 850-1050 ℃. The flue gas then enters an SNCR denitration device to remove NOx in the flue gas. The denitrated flue gas enters a secondary air mixing device, is fully mixed with the cooling flue gas at the outlet of a secondary air mixing fan and is cooled to 300-950 ℃, and the cooling air quantity entering the secondary air mixing device is adjusted by adjusting the opening degree of a valve on an air pipe connecting the secondary air mixing device and the secondary air mixing fan, so that the temperature of the cooled flue gas is optimally 650 ℃. The inlet of the secondary air mixing fan is connected with the outlet of the kiln tail bag for collecting dust, the outlet of the kiln tail bag for collecting dust is connected with a kiln tail chimney, and the inlet of the kiln tail bag for collecting dust is connected with the outlet of the kiln tail SP waste heat boiler. The hot flue gas cooled by the secondary air mixing device enters an air preheater, and exchanges heat with cold air input by an air blower through a heat exchange surface of the air preheater, the temperature of the air is increased to 200-800 ℃ after heat exchange, and the temperature of the flue gas after heat exchange is reduced to 100-360 ℃. The opening degree of a valve on an air inlet of the air preheater and an air pipe connected with a blower is adjusted, and the amount of cold air input into the air preheater is adjusted, so that the outlet temperature of hot air after heat exchange of the air preheater is optimally 450-550 ℃, and the temperature of outlet flue gas after heat exchange of the air preheater is optimally 160 ℃. Then the flue gas enters a dust collector for dust removal. And the flue gas after dust removal enters a kiln tail chimney through a tail exhaust fan to be discharged. The hot air at the outlet of the air preheater can be sent to a tertiary air pipe and enters the decomposing furnace as combustion-supporting air.

As shown in fig. 2, a kiln tail smoke chamber, a primary quenching device, an SNCR denitration device, a secondary air mixing device, an air preheater, a dust collector, a tail exhaust fan and a kiln tail chimney are sequentially connected through a flue, a cooling air inlet of the primary quenching device is connected with an outlet of the primary quenching fan, and an inlet of the primary quenching fan is connected with air; a cooling air inlet of the secondary air mixing device is connected with an outlet of a secondary air mixing fan, an inlet of the secondary air mixing fan is connected with a dust-collected outlet of a kiln tail bag, the dust-collected outlet of the kiln tail bag is simultaneously connected with a kiln tail chimney, and the dust-collected inlet of the kiln tail bag is connected with an outlet of a kiln tail SP waste heat boiler; and an air inlet of the air preheater is connected with an outlet of the air blower, and an air outlet of the air preheater is connected with an inlet of the SP waste heat boiler at the kiln tail.

The specific working process is as follows: an air discharge port is arranged at the enrichment part of the tail smoke chamber R +, Cl-and S of the cement kiln, part of high-temperature smoke with high R +, Cl-and S contents and the temperature of 1200 ℃ is extracted through a bypass air intake flue, and the high-temperature smoke enters a primary quenching device through a flue and is mixed and cooled with cold air from the outlet of a primary quenching fan. The temperature of the flue gas cooled by the primary quenching device is reduced to 500-1100 ℃, and the cooling air quantity entering the primary quenching device is adjusted by adjusting the opening degree of a valve on an air pipe connected with the primary quenching device and a primary quenching fan, so that the temperature of the cooled flue gas is optimally 850-1050 ℃. The flue gas then enters an SNCR denitration device to remove NOx in the flue gas. The denitrated flue gas enters a secondary air mixing device, is fully mixed with the cooling flue gas at the outlet of a secondary air mixing fan and is cooled to 300-950 ℃, and the cooling air quantity entering the secondary air mixing device is adjusted by adjusting the opening degree of a valve on an air pipe connecting the secondary air mixing device and the secondary air mixing fan, so that the temperature of the cooled flue gas is optimally 650 ℃. The inlet of the secondary air mixing fan is connected with the outlet of the kiln tail bag dust collection, the outlet of the kiln tail bag dust collection is connected with a kiln tail chimney, and the inlet of the kiln tail bag dust collection is connected with the outlet of the kiln tail SP waste heat boiler. The hot flue gas cooled by the secondary air mixing device enters an air preheater, and exchanges heat with cold air input by an air blower through a heat exchange surface of the air preheater, the temperature of the air is increased to 200-800 ℃ after heat exchange, and the temperature of the flue gas after heat exchange is reduced to 100-360 ℃. The opening degree of a valve on an air inlet of the air preheater and an air pipe connected with a blower is adjusted, and the amount of cold air input into the air preheater is adjusted, so that the outlet temperature of hot air after heat exchange of the air preheater is optimally 450-550 ℃, and the temperature of outlet flue gas after heat exchange of the air preheater is optimally 160 ℃. Then the flue gas enters a dust collector for dust removal. And the flue gas after dust removal enters a kiln tail chimney through a tail exhaust fan to be discharged. The hot air at the outlet of the air preheater can be sent to the inlet of the kiln tail SP waste heat boiler, so that the steam production of the kiln tail SP waste heat boiler is increased.

As shown in fig. 3, a kiln tail smoke chamber, a primary quenching device, an SNCR denitration device, a secondary air mixing device, an air preheater, a dust collector, a tail exhaust fan and a kiln tail chimney are sequentially connected through a flue, a cooling air inlet of the primary quenching device is connected with an outlet of the primary quenching fan, and an inlet of the primary quenching fan is connected with air; a cooling air inlet of the secondary air mixing device is connected with an outlet of a secondary air mixing fan, an inlet of the secondary air mixing fan is connected with a dust-collected outlet of a kiln tail bag, the dust-collected outlet of the kiln tail bag is simultaneously connected with a kiln tail chimney, and the dust-collected inlet of the kiln tail bag is connected with an outlet of a kiln tail SP waste heat boiler; an air inlet of the air preheater is connected with an outlet of the air blower, and an air outlet of the air preheater is connected with an inlet of the kiln head AQC waste heat boiler.

The specific working process is as follows: an air discharge port is arranged at the enrichment part of the tail smoke chamber R +, Cl-and S of the cement kiln, part of high-temperature smoke with high R +, Cl-and S contents and the temperature of 1200 ℃ is extracted through a bypass air intake flue, and the high-temperature smoke enters a primary quenching device through a flue and is mixed and cooled with cold air from the outlet of a primary quenching fan. The temperature of the flue gas cooled by the primary quenching device is reduced to 500-1100 ℃, and the cooling air quantity entering the primary quenching device is adjusted by adjusting the opening degree of a valve on an air pipe connected with the primary quenching device and a primary quenching fan, so that the temperature of the cooled flue gas is optimally 850-1050 ℃. The flue gas then enters an SNCR denitration device to remove NOx in the flue gas. The denitrated flue gas enters a secondary air mixing device, is fully mixed with the cooling flue gas at the outlet of a secondary air mixing fan and is cooled to 300-950 ℃, and the cooling air quantity entering the secondary air mixing device is adjusted by adjusting the opening degree of a valve on an air pipe connecting the secondary air mixing device and the secondary air mixing fan, so that the temperature of the cooled flue gas is optimally 650 ℃. The inlet of the secondary air mixing fan is connected with the outlet of the kiln tail bag dust collection, the outlet of the kiln tail bag dust collection is connected with a kiln tail chimney, and the inlet of the kiln tail bag dust collection is connected with the outlet of the kiln tail SP waste heat boiler. The hot flue gas cooled by the secondary air mixing device enters an air preheater, and exchanges heat with cold air input by an air blower through a heat exchange surface of the air preheater, the temperature of the air is increased to 200-800 ℃ after heat exchange, and the temperature of the flue gas after heat exchange is reduced to 100-360 ℃. The opening degree of a valve on an air inlet of the air preheater and an air pipe connected with a blower is adjusted, and the amount of cold air input into the air preheater is adjusted, so that the outlet temperature of hot air after heat exchange of the air preheater is optimally 450-550 ℃, and the temperature of outlet flue gas after heat exchange of the air preheater is optimally 160 ℃. Then the flue gas enters a dust collector for dust removal. And the flue gas after dust removal enters a kiln tail chimney through a tail exhaust fan to be discharged. The hot air at the outlet of the air preheater can be sent to the inlet of the kiln head AQC waste heat boiler, so that the steam production of the kiln head AQC boiler is increased.

As shown in FIG. 4, the first-stage quenching device is a cylindrical structure, two ends of the cylinder are connected with a flue gas pipeline, and a cooling air inlet is arranged at the tangential position of the side surface of the cylinder. The cooling air entering the cylinder through the cooling air tangential inlet rotates on the inner wall of the cylinder due to the inertia effect, so that a cooling layer is formed on the inner wall of the cylinder and completely wraps the hot flue gas, and the blockage caused by the adhesion of sticky dust in the high-temperature flue gas on the inner wall surface of the primary quenching device is fundamentally prevented.

As shown in fig. 5, the primary quenching device is composed of two concentric sleeves inside and outside, and the end of each sleeve is provided with an end plate, so that a closed cavity is formed between the two sleeves; wherein, interior sleeve pipe both ends are connected with flue gas pipeline, offer a plurality of holes on the interior sleeve pipe circumference wall, and the outer tube pipe wall is equipped with the cooling air entry. Because the cooling air radially enters the inner sleeve through the small holes on the wall surface of the inner sleeve, certain air pressure is generated, and dust is prevented from being adhered and blocked on the wall surface. Simultaneously, hot flue gas can mix with cooling air fast, the effectual temperature that reduces the flue gas.

Claims

1. The utility model provides a cement kiln is bypass of handling discarded object in coordination and is let out wind energy saving and emission reduction and utilize system and technology, includes kiln tail smoke chamber, one-level rapid cooling device, one-level rapid cooling fan, SNCR denitrification facility, second grade mix wind device, second grade mix wind fan, kiln tail bag and gather dust, kiln tail SP exhaust-heat boiler, air heater, air blower, dust collector, tail exhaust fan, kiln tail chimney, hot-blast operative installations, its characterized in that: the kiln tail smoke chamber, the primary quenching device, the SNCR denitration device, the secondary air mixing device, the air preheater, the dust collector, the tail exhaust fan and the kiln tail chimney are sequentially connected through a flue, a cooling air inlet of the primary quenching device is connected with an outlet of the primary quenching fan, and an inlet of the primary quenching fan is connected with air; a cooling air inlet of the secondary air mixing device is connected with an outlet of a secondary air mixing fan, an inlet of the secondary air mixing fan is connected with a dust-collected outlet of a kiln tail bag, the dust-collected outlet of the kiln tail bag is simultaneously connected with a kiln tail chimney, and the dust-collected inlet of the kiln tail bag is connected with an outlet of a kiln tail SP waste heat boiler; the air inlet of the air preheater is connected with the outlet of the air blower, and the air outlet of the air preheater is connected with the inlet of the hot air using device.

2. The bypass air-bleeding energy-saving emission-reduction utilization system and process for waste co-disposal of cement kiln according to claim 1 are characterized in that: the hot air using device is a tertiary air pipe or a kiln tail SP waste heat boiler or a kiln head AQC waste heat boiler.

3. The bypass air-bleeding energy-saving emission-reducing utilization system and process for waste co-disposal of cement kiln according to claim 2 are characterized in that: the flue gas outlet of the primary quenching device, the flue gas outlet of the secondary air mixing device, the hot air outlet of the air preheater and the hot flue gas outlet of the air preheater are respectively provided with a thermocouple.

4. The bypass air-bleeding energy-saving emission-reduction utilization system and process for waste co-disposal of cement kiln as claimed in claim 2, characterized in that: the primary quenching device is connected with a primary quenching fan and is provided with a valve for controlling air quantity; the secondary air mixing device and the secondary air mixing fan are connected with an air pipe, and a valve for controlling air quantity is arranged on the air pipe; and a valve for controlling the air quantity is arranged on the air inlet of the air preheater and the air blower connecting air pipe.

5. The bypass air-bleeding energy-saving emission-reduction utilization system and process for waste co-disposal of cement kiln as claimed in claim 2, characterized in that: the first-stage quenching device adopts a volute structure or a sleeve structure.

6. The bypass air-bleeding energy-saving emission-reduction utilization system and process for waste co-disposal of cement kiln according to claim 5, characterized in that: the first-stage quenching device of the volute structure is cylindrical, two ends of the cylinder are connected with a flue gas pipeline, and a cooling air inlet is arranged at the tangential position of the side surface of the cylinder.

7. The bypass air-bleeding energy-saving emission-reduction utilization system and process for waste co-disposal of cement kiln according to claim 5, characterized in that: the primary quenching device of the sleeve structure is composed of two concentric sleeves inside and outside, and the end part of each sleeve is provided with an end plate, so that a closed cavity is formed between the two sleeves; wherein, interior sleeve pipe both ends are connected with flue gas pipeline, offer a plurality of holes on the interior sleeve pipe circumference wall, and the outer tube pipe wall is equipped with the cooling air entry.

8. The bypass air-bleeding energy-saving emission-reduction utilization system and process for waste co-disposal by using the cement kiln as claimed in any one of claims 1 to 4, wherein: the temperature of the smoke outlet of the first-stage quenching device is 500-1100 ℃, the temperature of the smoke outlet of the second-stage air mixing device is 300-950 ℃, the temperature of the hot air outlet of the air preheater is 200-800 ℃, and the temperature of the hot smoke outlet of the air preheater is 100-360 ℃.