CN215428001U - Kiln waste gas waste heat recovery system - Google Patents

Abstract

The utility model discloses a kiln waste gas and waste heat recovery system, high-temperature waste gas from a kiln realizes waste heat utilization through a waste heat refrigerating device and a heat exchanger, the waste heat can be used for waste gas condensation and water removal, furnace entering oxygen heat exchange and rotary dehumidifier regeneration, the waste gas from a first-burning kiln can obtain oxygen with the concentration of more than 95% after wet impurity removal and secondary water removal, the oxygen can be directly used for secondary sintering of a high-nickel ternary material, the waste gas from a second-burning kiln can be used for heating primary sintering oxygen, and the rest waste gas can obtain the oxygen with the oxygen concentration of more than 97% after dust removal of a dust filtering device and water removal of a purifying device and carbon dioxide removal, and can be directly used for primary sintering, so that the cyclic regeneration of the oxygen is realized. The utility model realizes multiple utilization of waste heat and oxygen circulation regeneration, and has the advantages of low gas consumption, high efficiency and energy saving of the production process.

Description

Kiln waste gas waste heat recovery system

Technical Field

The utility model relates to the technical field of kiln tail gas recycling, in particular to a kiln waste gas and waste heat recycling system.

Background

With the rise of the new energy lithium ion battery industry, the high-nickel ternary material is paid attention to due to high energy density and long cycle life. How to reduce the production cost of the high-nickel ternary cathode material is a constant subject, and the cost is greatly reduced when the waste gas and waste heat are recycled by combining the condition of the pure oxygen sintering process of the existing long kiln. The related technology records an oxygen recycling device of a kiln for sintering the high-nickel ternary material, and only partial water vapor is removed through condensation, and in addition, other dust brought by exhaust gas can greatly influence the oxygen concentration, and the oxygen concentration required by sintering can not reach more than 95% to the greatest extent, so that the sintering effect of the high-nickel ternary material is influenced. In addition, a system for recycling the tail gas of the high-nickel kiln is also recorded, and the scheme only removes impurities from the discharged waste gas and then prepares oxygen again, so that the air oxygen preparation efficiency is further improved, and the oxygen generated after sintering in the kiln is not efficiently recycled. Therefore, it is necessary to develop a system capable of directly recycling oxygen and waste heat.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the utility model provides a kiln waste gas and waste heat recovery system which can efficiently recycle oxygen and waste heat in the sintering process of the high-nickel ternary cathode material so as to reduce the production cost.

The kiln waste gas and waste heat recovery system comprises a heat exchanger, a primary kiln, a waste heat refrigerating device, a wet dust collector, a condensing device, a rotary dehumidifier, a secondary kiln, a dust filtering device and a purifying device, wherein the rotary dehumidifier comprises a moisture absorption area and a regeneration area, gas enters the primary kiln through the heat exchanger, waste gas of the primary kiln sequentially passes through the waste heat refrigerating device, the wet dust collector, the condensing device and the moisture absorption area and then enters the secondary kiln, waste gas of the secondary kiln is used as a heating medium and is introduced into the heat exchanger and then sequentially introduced into the dust filtering device, the regeneration area and the purifying device, and an outlet of the purifying device is communicated with an inlet of the primary kiln, wherein the waste heat refrigerating device can be used for refrigerating the condensing device.

The kiln waste gas and waste heat recovery system provided by the embodiment of the utility model at least has the following beneficial effects:

1. waste heat utilization of high-temperature waste gas from the kiln is realized through a waste heat refrigerating device and a heat exchanger, and the waste heat can be used for waste gas condensation water removal, furnace entering oxygen heat exchange and rotary dehumidifier regeneration, so that waste heat energy is efficiently utilized;

2. the waste gas from the primary sintering kiln is subjected to wet impurity removal and secondary dehydration to obtain oxygen with the concentration of more than 95 percent, and the oxygen can be directly used for secondary sintering of the high-nickel ternary material;

3. the waste gas from the secondary combustion kiln can be used for heating fresh gas, further energy is saved, the residual waste gas is subjected to dust removal by a dust filtering device and water removal and carbon dioxide removal by a purification device to obtain oxygen with the oxygen concentration of more than 97%, and the oxygen can be directly used for primary sintering, so that the cyclic regeneration of the waste gas is realized.

4. The operation power of the waste gas and waste heat recovery system is mainly an induced draft fan and a water pump, so that the system has extremely low operation energy consumption, the operation cost is greatly saved, and in addition, the gas recovery of the system is mainly purification instead of pure oxygen production, so the recovery efficiency is high.

According to some embodiments of the utility model, the system is used in a sintering process of a high-nickel ternary cathode material, the fresh gas is fresh oxygen, and the high-temperature exhaust gas is high-temperature oxygen-rich exhaust gas.

According to some embodiments of the present invention, the waste heat refrigeration device is a lithium bromide water chiller, the lithium bromide water chiller comprises a generator and an evaporator, and the primary combustion kiln is communicated with the generator; condensing equipment includes cooling water cavity, condensation air chamber and first circulative cooling water pipe, the condensation air chamber is located the cooling water intracavity, the water accessible in the cooling water cavity first circulative cooling water pipe flows through the evaporimeter is in order to realize the heat exchange, condensation water and bottom that the bottom of condensation air chamber can bear dress comdenstion water and the bottom is equipped with drainage valve.

According to some embodiments of the present invention, the primary and/or secondary kilns include a cooling zone, and the condensing device further includes a second circulating cooling water pipe through which water in the cooling water chamber may flow through the cooling zone to achieve heat exchange.

According to some embodiments of the utility model, the condensing device further comprises a third recirculated cooling water pipe, the wet scrubber is a water curtain scrubber comprising a water tank, and water in the cooling water chamber may flow through the water tank through the third recirculated cooling water pipe to perform heat exchange.

According to some embodiments of the utility model, the purification apparatus is a molecular sieve purifier.

According to some embodiments of the utility model, an air storage tank is communicated between the moisture absorption zone and the secondary kiln.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the utility model.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the rotary dehumidifier of the present invention.

Reference numerals: the system comprises a heat exchanger 100, a primary combustion kiln 200, a cooling zone 210, an induced draft fan 300, a lithium bromide water chilling unit 400, a generator 410, an evaporator 420, a water curtain dust remover 500, a water tank 510, a condensing device 600, a condensing air chamber 610, a cooling water cavity 620, a first circulating cooling water pipe 630, a second circulating cooling water pipe 640, a third circulating cooling water pipe 650, a rotary dehumidifier 700, a moisture absorption zone 710, a regeneration zone 720, a gas storage tank 800, a secondary combustion kiln 900, a dust filter 1000, a molecular sieve purifier 1100 and a waste gas port 1110.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

Referring to fig. 1, a kiln waste gas and waste heat recovery system comprises a heat exchanger 100, a primary combustion kiln 200, a waste heat refrigerating device, a wet dust collector, a condensing device 600, a rotary dehumidifier 700, a secondary combustion kiln 900, a dust filtering device and a purifying device, wherein the rotary dehumidifier 700 comprises a moisture absorption area 710 and a regeneration area 720, gas enters the primary combustion kiln 200 through the heat exchanger 100, waste gas of the primary combustion kiln 200 sequentially passes through the waste heat refrigerating device, the wet dust collector, the condensing device 600 and the moisture absorption area 710 and then enters the secondary combustion kiln 900, waste gas of the secondary combustion kiln 900 is used as a heating medium and is introduced into the heat exchanger 100 and then sequentially introduced into the dust filtering device, the regeneration area 720 and the purifying device, an outlet of the purifying device is communicated with an inlet of the primary combustion kiln 200, and the waste heat refrigerating device can be used for refrigerating the condensing device 600.

In some embodiments, the waste heat refrigerating device is a lithium bromide water chilling unit 400, the lithium bromide water chilling unit 400 comprises a generator 410 and an evaporator 420, and the primary combustion kiln 200 is communicated with the generator 410; the condensing device 600 includes a cooling water cavity 620, a condensing air chamber 610 and a first circulating cooling water pipe 630, the condensing air chamber 610 is disposed in the cooling water cavity 620, water in the cooling water cavity 620 can flow through the evaporator 420 through the first circulating cooling water pipe 630 to realize heat exchange, the bottom of the condensing air chamber 610 can contain condensed water and the bottom is provided with a drain valve.

In some embodiments, the primary and/or secondary kilns 200, 900 include the cooling zone 210, and the condensing unit 600 further includes a second circulating cooling water pipe 640, and water in the cooling water chamber 620 may flow through the cooling zone 210 through the second circulating cooling water pipe 640 to perform heat exchange.

In some embodiments, the condensing unit 600 further includes a third recirculated cooling water pipe 650, the wet scrubber is a water curtain scrubber 500, the water curtain scrubber 500 includes a water tank 510, and water in the cooling water chamber 620 may flow through the water tank 510 through the third recirculated cooling water pipe 650 to achieve heat exchange.

In some of these embodiments, the purification device is a molecular sieve purifier 1100.

In some embodiments, an air storage tank 800 is communicated between the moisture absorption zone 710 and the secondary kiln 900.

The working principle of the system is as follows:

fresh oxygen enters from an inlet valve, is heated by a heat exchanger 100 and then enters a primary combustion kiln 200, high-temperature oxygen-enriched waste gas (400-.

The waste gas after dust removal is introduced into the condensation air chamber 610 of the condensation device 600, and the temperature of the condensation air chamber 610 is very low due to the fact that the cooling water is wrapped around the condensation air chamber 610, and then the water vapor in the waste gas is condensed and dehumidified. It should be noted that the cooling water in the cooling water cavity 620 is cooled by the evaporator 420 of the lithium bromide water chilling unit 400, and the specific principle is as follows: after the lithium bromide water solution is heated by the high-temperature waste gas in the generator 410, water in the solution is continuously vaporized, along with the continuous vaporization of the water, the concentration of the lithium bromide water solution in the generator 410 is continuously increased, the lithium bromide water solution enters the absorber, water vapor enters the condenser, the lithium bromide water solution is condensed after being cooled by cooling water in the condenser to form high-pressure low-temperature liquid water, when the water in the condenser enters the evaporator 420 through the throttle valve, the high-pressure low-temperature liquid water is rapidly expanded and vaporized, when the water in the cooling water cavity 620 enters the evaporator 420 through the first circulating cooling water pipe 630, a large amount of heat of the water in the evaporator 420 is absorbed in the vaporization process, and the cooled water returns to the cooling water cavity 620 from the evaporator 420, so that the condensing device 600 has the effects of cooling and refrigeration. In addition, the cooling water is also introduced into the water tank 510 of the water curtain dust collector 500 through the second circulating cooling water pipe 640 to cool the exhaust gas, and the cooling water is also introduced into the cooling zone 210 of the primary combustion kiln 200 through the third circulating cooling water pipe 650 to cool the material in the cooling zone 210. The condensed and dehumidified waste gas enters a moisture absorption area 710 of the rotary dehumidifier 700 for deep water removal, and primary recovered oxygen with the purity of more than 95% is obtained after the waste gas is discharged.

The primary recovered oxygen enters a gas storage tank 800 for caching, is directly introduced into a secondary sintering kiln 900 through an inlet valve and is used for the secondary sintering process of the high-nickel ternary anode material, high-temperature oxygen-enriched waste gas (200-.

Introducing the oxygen-enriched waste gas which is dedusted and has residual heat (80-200 ℃) into a regeneration zone 720 of the rotary dehumidifier 700 to recover the activity of the moisture absorption zone 710, wherein the structural schematic diagram of the rotary dehumidifier 700 is shown in FIG. 2. And finally, the oxygen-enriched waste gas enters a molecular sieve purifier 1100 for adsorption and purification of carbon dioxide and water to obtain secondary recovered oxygen with the purity of more than 97%, and the carbon dioxide and the water adsorbed by the molecular sieve purifier 1100 are directly discharged from a waste gas port 1110.

The secondary recovered oxygen is introduced into the primary combustion kiln 200 again for recycling through an inlet valve and fresh oxygen according to the volume ratio of 10 (1-10).

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.

Claims (6)

1. The kiln waste gas and waste heat recovery system is characterized by comprising a heat exchanger (100), a primary burning kiln (200), a waste heat refrigerating device, a wet dust collector, a condensing device (600), a rotary dehumidifier (700), a secondary burning kiln (900), a dust filtering device and a purifying device, wherein the rotary dehumidifier (700) comprises a moisture absorption area (710) and a regeneration area (720), gas enters the primary burning kiln (200) through the heat exchanger (100), waste gas of the primary burning kiln (200) sequentially passes through the waste heat refrigerating device, the wet dust collector, the condensing device (600) and the moisture absorption area (710) and then enters the secondary burning kiln (900), waste gas of the secondary burning kiln (900) is used as a heating medium and introduced into the heat exchanger (100) and then sequentially introduced into the dust filtering device, the regeneration area (720) and the purifying device, an outlet of the purifying device is communicated with an inlet of the primary burning kiln (200), wherein the waste heat refrigerating device can be used for refrigerating the condensing device (600).

2. The kiln waste gas and waste heat recovery system as claimed in claim 1, wherein the waste heat refrigerating device is a lithium bromide water chilling unit (400), the lithium bromide water chilling unit (400) comprises a generator (410) and an evaporator (420), and the primary kiln (200) is communicated with the generator (410); condensing equipment (600) includes cooling water cavity (620), condensation air chamber (610) and first circulative cooling water pipe (630), condensation air chamber (610) are located in cooling water cavity (620), the water accessible in cooling water cavity (620) first circulative cooling water pipe (630) flow through evaporimeter (420) is in order to realize the heat exchange, condensation water can be held in the bottom of condensation air chamber (610) and the bottom is equipped with drainage valve.

3. The kiln exhaust gas waste heat recovery system according to claim 2, wherein the primary kiln (200) and/or the secondary kiln (900) comprises a cooling zone (210), the condensing device (600) further comprises a second circulating cooling water pipe (640), and water in the cooling water chamber (620) can flow through the cooling zone (210) through the second circulating cooling water pipe (640) to realize heat exchange.

4. The kiln exhaust gas waste heat recovery system according to claim 2, wherein the condensing unit (600) further comprises a third recirculated cooling water pipe (650), the wet dust collector is a water curtain dust collector (500), the water curtain dust collector (500) comprises a water tank (510), and water in the cooling water chamber (620) can flow through the water tank (510) through the third recirculated cooling water pipe (650) to achieve heat exchange.

5. The kiln exhaust gas waste heat recovery system of claim 1, wherein the purification device is a molecular sieve purifier (1100).

6. The kiln exhaust gas waste heat recovery system of claim 1, wherein an air storage tank (800) is further communicated between the moisture absorption zone (710) and the secondary kiln (900).

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