CN111320187A - Urea pyrolysis system and urea pyrolysis method - Google Patents
Urea pyrolysis system and urea pyrolysis method Download PDFInfo
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- CN111320187A CN111320187A CN202010065671.1A CN202010065671A CN111320187A CN 111320187 A CN111320187 A CN 111320187A CN 202010065671 A CN202010065671 A CN 202010065671A CN 111320187 A CN111320187 A CN 111320187A
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- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/02—Preparation, purification or separation of ammonia
- C01C1/08—Preparation of ammonia from nitrogenous organic substances
- C01C1/086—Preparation of ammonia from nitrogenous organic substances from urea
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Abstract
The invention discloses a urea pyrolysis system which comprises a boiler, a high-temperature dust removal device and a pyrolysis furnace, wherein a low-temperature superheater and an economizer arranged below the low-temperature superheater are arranged in the boiler, a flue gas outlet is formed in a flue between the low-temperature superheater and the economizer, the high-temperature dust removal device is connected with the flue gas outlet, and the high-temperature dust removal device is connected with the pyrolysis furnace through a transfer flue. The device has a simple structure, and the flue between the low-temperature superheater and the economizer is provided with the flue gas outlet, so that high-temperature flue gas is led out by the flue gas outlet, is subjected to dust removal treatment by the high-temperature dust removal device and then is conveyed to the pyrolysis furnace for urea solution pyrolysis treatment; the invention omits an electric heater with high power consumption in the prior urea pyrolysis system, and reduces the power consumption and the operation cost of the urea pyrolysis system.
Description
Technical Field
The invention relates to a urea pyrolysis system and a method for pyrolyzing urea, and belongs to the field of urea pyrolysis treatment.
Background
Urea pyrolysis in the traditional urea pyrolysis system is mainly carried out in the pyrolysis reactor, and gas is heated by the heating device and then is used as a reaction heat source to enter the pyrolysis reactor for completely decomposing and conveying urea to the ammonia injection system. The heating device in the traditional urea pyrolysis system needs to use an electric heater with high power, so that the power consumption of the system is high, and the running cost is high.
Disclosure of Invention
The invention aims to provide a urea pyrolysis system and a method for pyrolyzing urea, which have low power consumption and low operation cost.
In order to solve the technical problems, the invention adopts the following technical scheme: the utility model provides a urea pyrolysis system, includes boiler, high temperature dust collector, pyrolysis oven, be provided with low temperature over heater in the boiler and set up the economizer in low temperature over heater below, flue department between low temperature over heater and the economizer is provided with the exhanst gas outlet, and high temperature dust collector is connected with the exhanst gas outlet, high temperature dust collector is connected with the pyrolysis oven through crossing the flue.
In the urea pyrolysis system, the transition flue is provided with the high-temperature induced draft fan and comprises a first transition flue section and a second transition flue section, the high-temperature dust removal device is connected with the air inlet of the high-temperature induced draft fan through the first transition flue section, and the pyrolysis furnace is connected with the air outlet of the high-temperature induced draft fan through the second transition flue section.
Among the aforementioned urea pyrolysis system, still include measurement distribution module, urea solution storage tank, first urea solution conveyer pipe and second urea solution conveyer pipe, measurement distribution module passes through first urea solution conveyer pipe and is connected with the urea solution storage tank, and measurement distribution module passes through the second urea solution conveyer pipe and is connected with the pyrolysis oven.
In the urea pyrolysis system, a spray gun device is arranged in the pyrolysis furnace, and the metering and distributing module is connected with the spray gun device arranged in the pyrolysis furnace.
In the urea pyrolysis system, the urea pyrolysis system further comprises a compressed air system and a compressed air delivery pipe, and the compressed air system is connected to the second urea solution delivery pipe through the compressed air delivery pipe.
In the urea pyrolysis system, the system further comprises an ammonia injection system, and the pyrolysis furnace is connected with the ammonia injection system.
The method for pyrolyzing urea by using the urea pyrolysis system comprises the following steps:
step S01: high-temperature flue gas is led out from a flue gas outlet of the boiler,
step S02: removing smoke dust in the high-temperature flue gas through a high-temperature dust removal device to obtain high-temperature clean flue gas;
step S03: conveying high-temperature clean flue gas to a pyrolysis furnace through a high-temperature induced draft fan; meanwhile, quantitatively conveying the urea solution to a pyrolysis furnace through a metering and distributing module, and decomposing the urea solution by using high-temperature clean flue gas to generate ammonia gas;
step S04: and conveying the mixed gas of the ammonia gas and the high-temperature clean flue gas to an ammonia spraying system.
Compared with the prior art, the device has a simple structure, the flue gas outlet is arranged at the flue between the low-temperature superheater and the economizer, high-temperature flue gas is led out by the flue gas outlet, and is conveyed to the pyrolysis furnace after being subjected to dust removal treatment by the high-temperature dust removal device for urea solution pyrolysis treatment; the invention omits an electric heater with high power consumption in the prior urea pyrolysis system, and reduces the power consumption and the operation cost of the urea pyrolysis system.
Taking 1 boiler with 300MW as an example, the urea consumption is 220kg/h, although the high-temperature induced draft fan (with the power of 45kWh/h) is added in the urea pyrolysis system, the electric heater (with the power of 600kWh/h) in the traditional urea pyrolysis system is omitted, the urea pyrolysis system can save 555kWh of electricity consumption per hour and the electricity consumption cost is about 80 ten thousand yuan per year. Compared with the traditional urea pyrolysis system, the initial investment of the urea pyrolysis system is increased by about 120 ten thousand yuan, the recoverable cost is 1.5 years, and the design life of the urea pyrolysis system is 30 years.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic structural view of the present invention.
Reference numerals: the method comprises the following steps of 1-a boiler, 2-a high-temperature dust removal device, 3-a pyrolysis furnace, 4-a low-temperature superheater, 5-an economizer, 6-a flue gas outlet, 7-a transition flue, 701-a first transition flue section, 702-a second transition flue section, 8-a high-temperature induced draft fan, 9-a metering distribution module, 10-a urea solution storage tank, 11-a first urea solution conveying pipe, 12-a second urea solution conveying pipe, 13-a spray gun device, 14-a compressed air system, 15-a compressed air conveying pipe and 16-an ammonia spraying system.
The invention is further described with reference to the following figures and detailed description.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings in the embodiments of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Example 1 of the invention: the utility model provides a urea pyrolysis system, includes boiler 1, high temperature dust collector 2, pyrolysis oven 3, be provided with low temperature over heater 4 in the boiler 1 and set up in economizer 5 of low temperature over heater 4 below, flue department between low temperature over heater 4 and the economizer 5 is provided with exhanst gas outlet 6, high temperature dust collector 2 is connected with pyrolysis oven 3 through crossing flue 7.
Example 2 of the invention: the utility model provides a urea pyrolysis system, includes boiler 1, high temperature dust collector 2, pyrolysis oven 3, be provided with low temperature over heater 4 in the boiler 1 and set up in economizer 5 of low temperature over heater 4 below, flue department between low temperature over heater 4 and the economizer 5 is provided with exhanst gas outlet 6, high temperature dust collector 2 is connected with pyrolysis oven 3 through crossing flue 7. Be provided with high temperature draught fan 8 on transition flue 7, transition flue 7 includes first transition flue section 701 and second transition flue section 702, high temperature dust collector 2 is through the air intake connection of first transition flue section 701 with high temperature draught fan 8, pyrolysis oven 3 is connected with the air outlet of high temperature draught fan 8 through second transition flue section 702.
Example 3 of the invention: the utility model provides a urea pyrolysis system, includes boiler 1, high temperature dust collector 2, pyrolysis oven 3, be provided with low temperature over heater 4 in the boiler 1 and set up in economizer 5 of low temperature over heater 4 below, flue department between low temperature over heater 4 and the economizer 5 is provided with exhanst gas outlet 6, high temperature dust collector 2 is connected with pyrolysis oven 3 through crossing flue 7. Be provided with high temperature draught fan 8 on transition flue 7, transition flue 7 includes first transition flue section 701 and second transition flue section 702, high temperature dust collector 2 is through the air intake connection of first transition flue section 701 with high temperature draught fan 8, pyrolysis oven 3 is connected with the air outlet of high temperature draught fan 8 through second transition flue section 702. The urea pyrolysis system further comprises a metering and distributing module 9, a urea solution storage tank 10, a first urea solution conveying pipe 11 and a second urea solution conveying pipe 12, wherein the metering and distributing module 9 is connected with the urea solution storage tank 10 through the first urea solution conveying pipe 11, and the metering and distributing module 9 is connected with the pyrolysis furnace 3 through the second urea solution conveying pipe 12.
Example 4 of the invention: the utility model provides a urea pyrolysis system, includes boiler 1, high temperature dust collector 2, pyrolysis oven 3, be provided with low temperature over heater 4 in the boiler 1 and set up in economizer 5 of low temperature over heater 4 below, flue department between low temperature over heater 4 and the economizer 5 is provided with exhanst gas outlet 6, high temperature dust collector 2 is connected with pyrolysis oven 3 through crossing flue 7. Be provided with high temperature draught fan 8 on transition flue 7, transition flue 7 includes first transition flue section 701 and second transition flue section 702, high temperature dust collector 2 is through the air intake connection of first transition flue section 701 with high temperature draught fan 8, pyrolysis oven 3 is connected with the air outlet of high temperature draught fan 8 through second transition flue section 702. The urea pyrolysis system further comprises a metering and distributing module 9, a urea solution storage tank 10, a first urea solution conveying pipe 11 and a second urea solution conveying pipe 12, wherein the metering and distributing module 9 is connected with the urea solution storage tank 10 through the first urea solution conveying pipe 11, and the metering and distributing module 9 is connected with the pyrolysis furnace 3 through the second urea solution conveying pipe 12. A spray gun device 13 is arranged in the pyrolysis furnace 3, and the metering and distributing module 9 is connected with the spray gun device 13 arranged in the pyrolysis furnace 3.
Example 5 of the invention: the utility model provides a urea pyrolysis system, includes boiler 1, high temperature dust collector 2, pyrolysis oven 3, be provided with low temperature over heater 4 in the boiler 1 and set up in economizer 5 of low temperature over heater 4 below, flue department between low temperature over heater 4 and the economizer 5 is provided with exhanst gas outlet 6, high temperature dust collector 2 is connected with pyrolysis oven 3 through crossing flue 7. Be provided with high temperature draught fan 8 on transition flue 7, transition flue 7 includes first transition flue section 701 and second transition flue section 702, high temperature dust collector 2 is through the air intake connection of first transition flue section 701 with high temperature draught fan 8, pyrolysis oven 3 is connected with the air outlet of high temperature draught fan 8 through second transition flue section 702. The urea pyrolysis system further comprises a metering and distributing module 9, a urea solution storage tank 10, a first urea solution conveying pipe 11 and a second urea solution conveying pipe 12, wherein the metering and distributing module 9 is connected with the urea solution storage tank 10 through the first urea solution conveying pipe 11, and the metering and distributing module 9 is connected with the pyrolysis furnace 3 through the second urea solution conveying pipe 12. A spray gun device 13 is arranged in the pyrolysis furnace 3, and the metering and distributing module 9 is connected with the spray gun device 13 arranged in the pyrolysis furnace 3. The urea pyrolysis system further comprises a compressed air system 14 and a compressed air delivery pipe 15, wherein the compressed air system 14 is connected to the second urea solution delivery pipe 12 through the compressed air delivery pipe 15. The delivered compressed air is mixed with the delivered urea solution in the second urea solution delivery pipe 12, and is delivered to the spray gun device 13 built in the pyrolysis furnace 3 together with the delivered urea solution, and is sprayed out through the spray gun device 13.
Example 6 of the invention: the utility model provides a urea pyrolysis system, includes boiler 1, high temperature dust collector 2, pyrolysis oven 3, be provided with low temperature over heater 4 in the boiler 1 and set up in economizer 5 of low temperature over heater 4 below, flue department between low temperature over heater 4 and the economizer 5 is provided with exhanst gas outlet 6, high temperature dust collector 2 is connected with pyrolysis oven 3 through crossing flue 7. Be provided with high temperature draught fan 8 on transition flue 7, transition flue 7 includes first transition flue section 701 and second transition flue section 702, high temperature dust collector 2 is through the air intake connection of first transition flue section 701 with high temperature draught fan 8, pyrolysis oven 3 is connected with the air outlet of high temperature draught fan 8 through second transition flue section 702. The urea pyrolysis system further comprises a metering and distributing module 9, a urea solution storage tank 10, a first urea solution conveying pipe 11 and a second urea solution conveying pipe 12, wherein the metering and distributing module 9 is connected with the urea solution storage tank 10 through the first urea solution conveying pipe 11, and the metering and distributing module 9 is connected with the pyrolysis furnace 3 through the second urea solution conveying pipe 12. A spray gun device 13 is arranged in the pyrolysis furnace 3, and the metering and distributing module 9 is connected with the spray gun device 13 arranged in the pyrolysis furnace 3. The urea pyrolysis system further comprises a compressed air system 14 and a compressed air delivery pipe 15, wherein the compressed air system 14 is connected to the second urea solution delivery pipe 12 through the compressed air delivery pipe 15. The delivered compressed air is mixed with the delivered urea solution in a second urea solution delivery pipe 12, and is delivered to a spray gun device 13 arranged in the pyrolysis furnace 3 together, and is sprayed out through the spray gun device 13, the urea pyrolysis system further comprises an ammonia spraying system 16, and the pyrolysis furnace 3 is connected with the ammonia spraying system 16.
Embodiment 7 of the present invention: a method for pyrolyzing urea, step S01: leading out high-temperature flue gas from a flue gas outlet of the boiler;
step S02: removing smoke dust in the high-temperature flue gas through a high-temperature dust removal device to obtain high-temperature clean flue gas; step S03: conveying high-temperature clean flue gas to a pyrolysis furnace through a high-temperature induced draft fan; meanwhile, quantitatively conveying the urea solution to a pyrolysis furnace through a metering and distributing module 9, and decomposing the urea solution by using high-temperature clean flue gas to generate ammonia gas; step S04: and conveying the mixed gas of the ammonia gas and the high-temperature clean flue gas to an ammonia spraying system.
The working principle of the invention is as follows:
high-temperature flue gas is led out from a flue gas outlet 6 between a low-temperature superheater 4 and an economizer 5 of a tail flue of the boiler 1, smoke dust in the high-temperature flue gas is removed through a high-temperature dust removal device 2 to obtain high-temperature clean flue gas, and the high-temperature clean flue gas is sent to a pyrolysis furnace 3 through a high-temperature induced draft fan 8 to be used for decomposing urea solution. The urea solution from the metering module 9 is sprayed to the pyrolysis furnace 3 under the atomization effect of the compressed air, the urea solution is decomposed in the high-temperature clean flue gas in the pyrolysis furnace 3 to generate ammonia gas, and finally the mixed gas of the ammonia gas and the flue gas (the temperature of the flue gas is reduced at this time) is sent to an ammonia spraying system 16.
Claims (7)
1. The utility model provides a urea pyrolysis system, its characterized in that, includes boiler (1), high temperature dust collector (2), pyrolysis oven (3), be provided with low temperature over heater (4) in boiler (1) and set up in economizer (5) of low temperature over heater (4) below, flue department between low temperature over heater (4) and economizer (5) is provided with exhanst gas outlet (6), high temperature dust collector (2) are connected with pyrolysis oven (3) through crossing flue (7).
2. The urea pyrolysis system of claim 1, wherein a high-temperature induced draft fan (8) is arranged on the transition flue (7), the transition flue (7) comprises a first transition flue section (701) and a second transition flue section (702), the high-temperature dust removal device (2) is connected with an air inlet of the high-temperature induced draft fan (8) through the first transition flue section (701), and the pyrolysis furnace (3) is connected with an air outlet of the high-temperature induced draft fan (8) through the second transition flue section (702).
3. A urea pyrolysis system according to claim 2, further comprising a metering and distributing module (9), a urea solution storage tank (10), a first urea solution delivery pipe (11) and a second urea solution delivery pipe (12), wherein the metering and distributing module (9) is connected with the urea solution storage tank (10) through the first urea solution delivery pipe (11), and the metering and distributing module (9) is connected with the pyrolysis furnace (3) through the second urea solution delivery pipe (12).
4. A urea pyrolysis system according to claim 3, wherein the pyrolysis furnace (3) is provided with a lance device (13), and the metering and distributing module (9) is connected with the lance device (13) provided in the pyrolysis furnace (3).
5. A urea pyrolysis system according to claim 4, further comprising a compressed air system (14) and a compressed air duct (15), the compressed air system (14) being connected to the second urea solution duct (12) by means of the compressed air duct (15).
6. A urea pyrolysis system according to claim 5, further comprising an ammonia injection system (16), wherein the pyrolysis furnace (3) is connected to the ammonia injection system (16).
7. A method for pyrolyzing urea by using the urea pyrolysis system of any one of claims 1 to 6, comprising the steps of:
step S01: leading out high-temperature flue gas from a flue gas outlet of the boiler;
step S02: removing smoke dust in the high-temperature flue gas through a high-temperature dust removal device to obtain high-temperature clean flue gas;
step S03: conveying high-temperature clean flue gas to a pyrolysis furnace through a high-temperature induced draft fan; meanwhile, quantitatively conveying the urea solution to a pyrolysis furnace through a metering and distributing module, and decomposing the urea solution by using high-temperature clean flue gas to generate ammonia gas;
step S04: and conveying the mixed gas of the ammonia gas and the high-temperature clean flue gas to an ammonia spraying system.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010065671.1A CN111320187A (en) | 2020-01-20 | 2020-01-20 | Urea pyrolysis system and urea pyrolysis method |
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| CN202010065671.1A CN111320187A (en) | 2020-01-20 | 2020-01-20 | Urea pyrolysis system and urea pyrolysis method |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3473894A (en) * | 1966-03-09 | 1969-10-21 | Lonza Werke Gmbh | Preparation of hexagonal boron nitride |
| CN205133164U (en) * | 2015-10-28 | 2016-04-06 | 沈阳洛卡环保工程有限公司 | System for utilize boiler bypass to carry out urea pyrolysis system ammonia |
| CN109761245A (en) * | 2019-03-22 | 2019-05-17 | 大唐环境产业集团股份有限公司 | A kind of urea pyrolysis ammonia-preparing device and technique based on high-temperature flue gas |
| CN209020198U (en) * | 2018-10-16 | 2019-06-25 | 中国华电科工集团有限公司 | A kind of urea liquid pyrolysis installation applied to denitrating system |
-
2020
- 2020-01-20 CN CN202010065671.1A patent/CN111320187A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3473894A (en) * | 1966-03-09 | 1969-10-21 | Lonza Werke Gmbh | Preparation of hexagonal boron nitride |
| CN205133164U (en) * | 2015-10-28 | 2016-04-06 | 沈阳洛卡环保工程有限公司 | System for utilize boiler bypass to carry out urea pyrolysis system ammonia |
| CN209020198U (en) * | 2018-10-16 | 2019-06-25 | 中国华电科工集团有限公司 | A kind of urea liquid pyrolysis installation applied to denitrating system |
| CN109761245A (en) * | 2019-03-22 | 2019-05-17 | 大唐环境产业集团股份有限公司 | A kind of urea pyrolysis ammonia-preparing device and technique based on high-temperature flue gas |
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Application publication date: 20200623 |