CN202880910U - Cold energy utilization device in high-purity ammonia preparation process - Google Patents

Cold energy utilization device in high-purity ammonia preparation process Download PDF

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Publication number
CN202880910U
CN202880910U CN 201220590163 CN201220590163U CN202880910U CN 202880910 U CN202880910 U CN 202880910U CN 201220590163 CN201220590163 CN 201220590163 CN 201220590163 U CN201220590163 U CN 201220590163U CN 202880910 U CN202880910 U CN 202880910U
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cold
ammonia
interconnection
exchange
vertical passage
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Withdrawn - After Issue
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CN 201220590163
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Chinese (zh)
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鲍坚仁
鲍坚斌
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HUNAN HIEND-PRODUCTS NEW MATERIALS Co Ltd
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HUNAN HIEND-PRODUCTS NEW MATERIALS Co Ltd
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Abstract

The utility model relates to a cold energy utilization device in a high-purity ammonia preparation process, which comprises a cold exchanger, an ammonia cooler, a chiller, a liquid nitrogen cold exchanger and an ammonia separator, wherein the cold exchanger is connected with the ammonia cooler through a first pipeline; the ammonia cooler is connected with the chiller through a second pipeline; the chiller is connected with the liquid nitrogen cold exchanger through a third pipeline; the liquid nitrogen cold exchanger is connected with the ammonia separator through a fourth pipeline; the ammonia separator is provided with two outlet ends; a first outlet end is connected with and communicated with an inlet end of a longitudinal channel of the cold exchanger through a fifth pipeline; and a second outlet end is connected with a high-purity liquid ammonia discharge pipe. The utility model is based on the technical scheme disclosed by a patent ZL 2009100662709.3 and can fully utilize cold energy generated in the technology to reduce energy consumption, and the cold energy almost accounts for 50-85% of the cold energy required for the whole refrigeration process, thereby greatly lowering the production cost.

Description

Cryogenic energy utilization device among the high-purity ammon preparation technology
Technical field
The utility model belongs to energy-saving field, relates to energy utilization device in a kind of synthetic high-purity ammon, especially relates to cryogenic energy utilization device among a kind of high-purity ammon preparation technology.
Background technology
The industrial expansions such as modern microelectronics and photoelectron are to nitride particularly gan (GaN) and silicon nitride (Si 3N 4) higher specification of quality proposed.In the high-quality nitride of preparation, must use highly purified ammonia (high-purity ammon), the purity of high-purity ammon need to be more than 99.9999% usually.Chinese patent ZL2009100662709.3, name is called " ammonia catalytic pyrolysis, hydrogen and nitrogen gas purifying and the integrated method for preparing high-purity ammon of three step of ammonia synthesis " and discloses a kind of traditional novel method that rectifying obtains high-purity ammon of passing through that is different from: the technique that obtains high-purity ammon in this patent, existing high temperature flow process: such as the required high temperature of ammonia catalytic pyrolysis (about 800 ℃) and the required high temperature (about 400 ℃) of ammonia synthesis, cryogenic system is arranged also: need after the ammonia synthesis medium (comprising ammonia, hydrogen nitrogen mixed gas) is reduced to low temperature (usually below-25 ℃).These processes all need to consume considerable energy, and how to reduce energy consumption in these technical process is an important problem, mean the reduction cost because reduce energy consumption.In this patent, aspect the utilizing of energy, also there is following defective:
1) in this step of ammonia synthesis of three-step approach, after obtaining high-purity ammonia, also need ammonia is separated with hydrogen nitrogen mixed gas, in order to separate as far as possible ammonia and hydrogen nitrogen mixed gas, separate usually and need to be down to low temperature below-25~-50 ℃ to the medium refrigeration, separate by ammonia being liquefied as liquefied ammonia heel hydrogen nitrogen mixed gas, this step refrigeration needs to consume considerable energy.
2) at the ammonia catalytic pyrolysis of three-step approach in this step, need again hanging down pure ammonia (being generally liquefied ammonia rather than ammonia) heating and gasifying and then being warming up to about 800 ℃ high temperature, then be decomposed into hydrogen nitrogen mixed gas, this step also will consume considerable energy, the consumption of energy can be divided into three parts: intensification and the ammonia of the ammonia after the gasification of liquefied ammonia, the gasification decompose the energy that will consume as a thermo-negative reaction, and wherein the energy of front two portions consumption is substantially suitable.The gasification latent heat of liquefied ammonia is very large, and under an atmospheric condition, the gasification latent heat of 1 gram ammonia is 1368 joules, and this means the energy consumption that the liquid ammonia gasification needs are a large amount of on the one hand, means also that on the other hand liquefied ammonia contains a large amount of colds.
3) front need to reenter synthetic tower with Ammonia separation hydrogen nitrogen mixed gas out, and the hydrogen nitrogen mixed gas of just having separated also contains considerable cold, and these colds fail to be fully utilized.
4) in the high-purity ammon manufacturing processed, need to consume considerable nitrogen, be mainly used in the purging of the regeneration of purification system or pipeline, container etc., these nitrogen often get by liquid nitrogen gasification, and liquid nitrogen is a kind of extraordinary low-temperature receiver, and this liguefied nitrogen also fails to be used fully.
The utility model content
The technical problems to be solved in the utility model provides the use device of cold among a kind of high-purity ammon preparation technology.This device is on the basis of the technical scheme that Chinese patent ZL 2009100662709.3 provides, can take full advantage of the cold that produces in this technology and reduce energy consumption, these colds almost reach 50~85% of whole refrigeration institute chilling requirement, and production cost reduces greatly.
For solving the problems of the technologies described above, the utility model adopts following technical scheme:
The use device of cold among a kind of high-purity ammon preparation technology comprises cold-exchange, ammonia cooler, deep freezer, liquid nitrogen cold-exchange and ammonia separator;
Described cold-exchange comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described ammonia cooler comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described deep freezer comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described liquid nitrogen cold-exchange comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
High-purity ammon synthetic ammonia exhaust gas is after room temperature is down in overcooling, gas enters cold-exchange by the interconnection entrance end of cold-exchange, the interconnection exit end of cold-exchange is connected with ammonia cooler interconnection entrance end by the first pipeline and communicates, described ammonia cooler interconnection exit end is connected with deep freezer interconnection entrance end by second pipe and communicates, described deep freezer interconnection exit end is connected with liquid nitrogen cold-exchange interconnection entrance end by the 3rd pipeline and communicates, described liquid nitrogen cold-exchange interconnection exit end is connected with the ammonia separator entrance end by the 4th pipeline and communicates, described ammonia separator is provided with two exit end, the first exit end is connected with cold-exchange vertical passage inlet end by the 5th pipeline and communicates, and the second exit end connects high-purity liquefied ammonia vent pipe;
Described ammonia cooler vertical passage entrance end connects low pure liquefied ammonia input tube, and exit end connects the ammonia outlet pipe;
Described deep freezer vertical passage entrance end connects the refrigerant input tube, and exit end connects the refrigerant outlet pipe;
Described liquid nitrogen cold-exchange vertical passage entrance end connects the liquid nitrogen input tube, and exit end connects nitrogen outlet pipe.
Preferably, described cold-exchange, ammonia cooler, deep freezer and liquid nitrogen cold-exchange adopt the tube and shell heat exchanger structure.
Preferably, described cold-exchange, ammonia cooler, deep freezer and liquid nitrogen cold-exchange adopt stainless steel or carbon steel material.
Utilize said apparatus to the method for utilizing of cold among the high-purity ammon preparation technology, comprise the steps:
High-purity ammon synthetic tower medium out (comprises ammonia from the technical scheme of background technology, hydrogen nitrogen mixed gas) after overcooling, is down to room temperature, then through progressively successively cooling, after reaching at last below-25~-50 ℃, after most of ammonia liquefaction is liquefied ammonia, then separate with hydrogen nitrogen mixed gas and obtain high-purity ammon, complete cooling down flow process as shown in Figure 1, each step cooling is all finished by cold-exchange, the structure of cold-exchange is mainly selected tube and shell heat exchanger, materials'use stainless steel or the carbon steel of cold-exchange, for the very tight technique of the specification of quality of high-purity ammon, suggestion uses stainless material to make cold-exchange.Concrete step is as follows:
1) from high-purity ammon synthetic tower medium out is down to room temperature after overcooling after, is transported in the cold-exchange interconnection and lowers the temperature, the low temperature hydrogen nitrogen mixed gas in the cold-exchange vertical passage that the required cold of lowering the temperature is transported to by the 5th pipeline from ammonia separator; Rise near room temperature through the hydrogen nitrogen mixed gas behind the cold-exchange, the synthetic tower that then reenters in the patent ZL 2009100662709.3 disclosed technical schemes by recycle compressor begins next time synthesizing of ammonia;
2) medium is transported to further cooling in the ammonia cooler interconnection from cold-exchange interconnection exit end by the first pipeline; Pass into low pure liquefied ammonia in the vertical passage of cold-exchange, the low pure liquefied ammonia after the heat exchange becomes ammonia as the unstripped gas of catalytic pyrolysis in the patent ZL 2009100662709.3 disclosed technical schemes after gasifying;
3) medium is transported to further cooling in the deep freezer interconnection from ammonia cooler interconnection exit end by second pipe; Pass into the refrigerant that external refrigeration equipment makes in the vertical passage of deep freezer; Preferably, refrigerant is freonll-11, ammonia, ethanol or ethylene glycol; Preferably, refrigerant circulates between external refrigeration equipment and deep freezer.
4) medium is transported to further cooling in the liquid nitrogen cold-exchange interconnection from deep freezer interconnection exit end by the 3rd pipeline; Pass into liquid nitrogen in the vertical passage of liquid nitrogen cold-exchange, the liquid nitrogen after the heat exchange becomes behind the nitrogen sweep gas as the resurgent gases of purification system in the patent ZL 2009100662709.3 disclosed technical schemes or pipeline, container;
5) medium is transported in the ammonia separator by the 4th pipeline from liquid nitrogen cold-exchange interconnection exit end and separates, and high-purity liquefied ammonia is discharged from high-purity liquefied ammonia vent pipe and collected, and the hydrogen nitrogen mixed gas of separation is transported in the cold-exchange vertical passage as low-temperature receiver.
In the above step, only have the refrigeration of step 3) need to consume extra energy, we can be referred to as active refrigeration, and other steps all are to need not extra energy consumption for the cold that takes full advantage of the generation in the existing technical process, can be referred to as non-active refrigeration.So just saved widely the required energy consumption of cryogenic system, through experimental measurement and calculating, the cold that active refrigeration produces accounts for the required cold of whole cryogenic system and only has 15~50%.
Wherein, ammonia step 2) is cold, and to be that patent ZL 2009100662709.3 disclosed technical schemes prepare high-purity ammon institute exclusive.
Wherein, the utilization of the liquid nitrogen cold in the step 4) also is that the disclosed technical schemes of patent ZL 2009100662709.3 institute is exclusive, because tradition (low pure) ammonia process generally can not use liquid nitrogen yet, but high-purity ammon technique generally all needs a considerable amount of liquid nitrogen, liquid nitrogen gasification becomes to be used for providing the regeneration that purges pipe container etc. or purifier behind the nitrogen, reason is the very stable and safety of nitrogen, be easy to simultaneously be purified to 99.9999999% purity, nitrogen almost is applied to all high purity material manufacturing process.
The utlity model has following beneficial effect:
The utility model can take full advantage of the cold that produces in this technology and reduce energy consumption on the basis of patent ZL 2009100662709.3 disclosed technical schemes, and these colds almost reach 50~85% of whole refrigeration institute chilling requirement, and production cost reduces greatly.
Description of drawings
Below in conjunction with accompanying drawing embodiment of the present utility model is described in further detail
Fig. 1 is the utility model process flow diagram.
Embodiment
Embodiment 1
Referring to shown in Figure 1, the use device of cold among a kind of high-purity ammon preparation technology comprises cold-exchange 2, ammonia cooler 3, deep freezer 4, liquid nitrogen cold-exchange 5 and ammonia separator 6;
Described cold-exchange 2 comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described ammonia cooler 3 comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described deep freezer 4 comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described liquid nitrogen cold-exchange 5 comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
High-purity ammon synthetic ammonia exhaust gas is after room temperature is down in overcooling, gas enters cold-exchange 2 by the interconnection entrance end of cold-exchange, the interconnection exit end of cold-exchange 2 is connected with ammonia cooler 3 interconnection entrance ends by the first pipeline 701 and communicates, described ammonia cooler 3 interconnection exit end are connected with deep freezer 4 interconnection entrance ends by second pipe 702 and communicate, described deep freezer 4 interconnection exit end are connected with liquid nitrogen cold-exchange 5 interconnection entrance ends by the 3rd pipeline 703 and communicate, described liquid nitrogen cold-exchange 5 interconnection exit end are connected with ammonia separator 6 entrance ends by the 4th pipeline 704 and communicate, described ammonia separator 6 is provided with two exit end, the first exit end is connected with cold-exchange 2 vertical passage inlet ends by the 5th pipeline 705 and communicates, and the second exit end connects high-purity liquefied ammonia vent pipe 706;
Described ammonia cooler 3 vertical passage entrance ends connect low pure liquefied ammonia input tube 707, and exit end connects ammonia outlet pipe 708;
Described deep freezer 4 vertical passage entrance ends connect refrigerant input tube 709, and exit end connects refrigerant outlet pipe 710; Described refrigerant input tube 709 and refrigerant outlet pipe 710 external refrigeration equipment (not shown)s;
Described liquid nitrogen cold-exchange 5 vertical passage entrance ends connect liquid nitrogen input tube 711, and exit end connects nitrogen outlet pipe 712;
Described cold-exchange 2, ammonia cooler 3, deep freezer 4 and liquid nitrogen cold-exchange 5 adopt the tube and shell heat exchanger structure;
Described cold-exchange 2, ammonia cooler 3, deep freezer 4 and liquid nitrogen cold-exchange 5 adopt stainless steel.
Utilize said apparatus to the method for utilizing of cold among the high-purity ammon preparation technology, comprise the steps:
High-purity ammon synthetic tower medium (comprising ammonia, hydrogen nitrogen mixed gas) out need to be down to room temperature after overcooling from the technical scheme of background technology, then through progressively successively cooling, after reaching at last below-25~-50 ℃, after most of ammonia liquefaction is liquefied ammonia, then separate with hydrogen nitrogen mixed gas and obtain high-purity ammon, complete cooling down flow process as shown in Figure 1, concrete step is as follows:
1) from high-purity ammon synthetic tower medium out is down to room temperature after overcooling after, is transported in cold-exchange 2 interconnections and lowers the temperature, the low temperature hydrogen nitrogen mixed gas in cold-exchange 2 vertical passages that the required cold of lowering the temperature is transported to by the 5th pipeline 705 from ammonia separator 5; Rise near room temperature through the hydrogen nitrogen mixed gas behind the cold-exchange 2, the synthetic tower that then reenters in the patent ZL 2009100662709.3 disclosed technical schemes by recycle compressor begins next time synthesizing of ammonia;
2) medium is transported to further cooling in ammonia cooler 3 interconnections from cold-exchange 2 interconnection exit end by the first pipeline 701; Pass into low pure liquefied ammonia in the vertical passage of cold-exchange 2, the low pure liquefied ammonia after the heat exchange becomes ammonia as the unstripped gas of catalytic pyrolysis in the patent ZL 2009100662709.3 disclosed technical schemes after gasifying;
3) medium is transported to further cooling in deep freezer 4 interconnections from ammonia cooler 3 interconnection exit end by second pipe 702; Pass into the refrigerant that external refrigeration equipment makes in the vertical passage of deep freezer 4; Refrigerant is freonll-11, ammonia, ethanol or ethylene glycol; Refrigerant circulates between external refrigeration equipment and deep freezer.
4) medium is transported to further cooling in liquid nitrogen cold-exchange 5 interconnections from deep freezer 4 interconnection exit end by the 3rd pipeline 703; Pass into liquid nitrogen in the vertical passage of liquid nitrogen cold-exchange 5, the liquid nitrogen after the heat exchange becomes behind the nitrogen sweep gas as the resurgent gases of purification system in the patent ZL 2009100662709.3 disclosed technical schemes or pipeline, container;
5) medium is transported in the ammonia separator 6 by the 4th pipeline 704 from liquid nitrogen cold-exchange 5 interconnection exit end and separates, high-purity liquefied ammonia is discharged from high-purity liquefied ammonia vent pipe 706 and is collected, the hydrogen nitrogen mixed gas of separation in the 5th pipeline 705 is transported to cold-exchange 2 vertical passages as low-temperature receiver.
Obviously, above-described embodiment of the present utility model only is for the utility model example clearly is described, and is not to be restriction to embodiment of the present utility model.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here can't give all embodiments exhaustive.Everyly belong to the row that apparent variation that the technical solution of the utility model extends out or change still are in protection domain of the present utility model.

Claims (3)

1. the use device of cold among the high-purity ammon preparation technology is characterized in that, comprises cold-exchange, ammonia cooler, deep freezer, liquid nitrogen cold-exchange and ammonia separator;
Described cold-exchange comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described ammonia cooler comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described deep freezer comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
Described liquid nitrogen cold-exchange comprises interconnection and vertical passage, and interconnection and vertical passage are not communicated with mutually;
The interconnection exit end of described cold-exchange is connected with ammonia cooler interconnection entrance end by the first pipeline and communicates, described ammonia cooler interconnection exit end is connected with deep freezer interconnection entrance end by second pipe and communicates, described deep freezer interconnection exit end is connected with liquid nitrogen cold-exchange interconnection entrance end by the 3rd pipeline and communicates, described liquid nitrogen cold-exchange interconnection exit end is connected with the ammonia separator entrance end by the 4th pipeline and communicates, described ammonia separator is provided with two exit end, the first exit end is connected with cold-exchange vertical passage inlet end by the 5th pipeline and communicates, and the second exit end connects high-purity liquefied ammonia vent pipe;
Described ammonia cooler vertical passage entrance end connects low pure liquefied ammonia input tube, and exit end connects the ammonia outlet pipe;
Described deep freezer vertical passage entrance end connects the refrigerant input tube, and exit end connects the refrigerant outlet pipe;
Described liquid nitrogen cold-exchange vertical passage entrance end connects the liquid nitrogen input tube, and exit end connects nitrogen outlet pipe.
2. use device according to claim 1 is characterized in that: described cold-exchange, ammonia cooler, deep freezer and liquid nitrogen cold-exchange employing tube and shell heat exchanger structure.
3. use device according to claim 1 and 2 is characterized in that: described cold-exchange, ammonia cooler, deep freezer and liquid nitrogen cold-exchange employing stainless steel or carbon steel material.
CN 201220590163 2012-11-09 2012-11-09 Cold energy utilization device in high-purity ammonia preparation process Withdrawn - After Issue CN202880910U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102923731A (en) * 2012-11-09 2013-02-13 湖南高安新材料有限公司 Utilizing device and method for cold energy in high-purity ammonia preparation process

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102923731A (en) * 2012-11-09 2013-02-13 湖南高安新材料有限公司 Utilizing device and method for cold energy in high-purity ammonia preparation process

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Granted publication date: 20130417

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