MVR stripping method and system for zero-steam wastewater deamination

Abstract

The application provides a zero-steam wastewater deamination MVR stripping method and system, and belongs to the field of chemical equipment.The system comprises a rectifying tower, a discharge flash steam compressor, a feed flash steam compressor, a discharge falling film evaporator and a feed falling film evaporator;ammonia-containing wastewater is preheated through parallel connection of discharge and non-condensable gas, then enters the tube side of the feed falling film evaporator for evaporation, and then is combined with reflux dilute ammonia water to enter the rectifying tower;the overhead steam of the rectifying tower is subjected to three-stage heat recovery through the non-condensable gas preheater of the discharge falling film evaporator and the feed falling film evaporator, and then is subjected to non-condensable gas ammonia removal recovery;the deamination waste liquid at the bottom of the rectifying tower is discharged from the system after being subjected to tube side falling film evaporation and feed preheating;the discharge flash steam is combined with the overhead steam after being compressed, and the feed flash steam is pressurized to enter the rectifying tower as stripping steam;part of the dilute ammonia water condensed by the two falling film evaporators is refluxed to the rectifying tower, and part is sent to ammonia recovery.The secondary steam can meet the stripping deamination requirement, and fresh steam is not needed to be externally supplied.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of chemical equipment, and particularly relates to a zero-steam wastewater deamination MVR stripping method and system. BACKGROUND

[0002] A large amount of wastewater containing ammonia nitrogen is often generated in industrial production and needs to be treated before being discharged. In the treatment of wastewater containing ammonia nitrogen, ammonia in the wastewater is removed on the one hand, and nitrogen elements are recycled and utilized on the other hand.

[0003] At present, a method of steam stripping and rectification is generally used for deamination, and the basic process is that, by using externally supplied steam, wastewater containing ammonia nitrogen is stripped in a stripping section of a stripping tower, and then rectified in a rectification section to produce ammonia water of a certain concentration, so as to realize deamination. For example, a Chinese patent with the publication number CN114229936A discloses an ammonia water MVR stripping system and a stripping method thereof. The wastewater containing ammonia is delivered into a rectification tower through a feed inlet by using an external material delivery device, and at the same time, primary fresh steam is continuously delivered into the rectification tower through an air inlet. The two ends of a pipe passage of a falling film heat exchanger are connected by a pipeline and are provided with a circulating delivery pump for circulating and delivering the liquid in the pipe passage. A first evaporation chamber and a second steam compressor are arranged between a liquid outlet at the bottom of the pipe passage of the falling film heat exchanger and an air inlet of a falling film evaporator. The first evaporation chamber heats and vaporizes the liquid in the falling film heat exchanger, and then delivers the vaporized steam to the second steam compressor to compress the steam to the required temperature of the falling film evaporator. However, the above treatment process needs to continuously input fresh steam, which increases the consumption of steam in the tower kettle and cooling water at the top of the rectification tower, thereby greatly increasing the energy consumption. SUMMARY

[0004] In view of the above defects or deficiencies in the prior art, the embodiments of the present application aim to provide a zero-steam wastewater deamination MVR stripping method and system, which effectively combines a rectification tower with a falling film evaporator, only needs to input initial steam in the system startup and temperature rising stage, and realizes steam self-provision after the system is normally operated, so as to fully recover the heat of the system, realize fresh steam zero consumption on the premise of ensuring the deamination effect, improve the energy utilization rate, and achieve energy saving and emission reduction.

[0005] In order to achieve the above purpose, the embodiments of the present application adopt the following technical solutions:

[0006] In a first aspect, the embodiments of the present application provide a zero-steam wastewater deamination MVR stripping system, which comprises a rectification tower 1, a discharge flash steam compressor 2, a feed flash steam compressor 3, a discharge falling film evaporator 4, a feed falling film evaporator 5, a steam saturator 6, a first feed preheater 7, a second feed preheater 8, a third feed preheater 9, a dilute ammonia water reflux tank 10, an ammonia water reflux pump 11, a discharge pump 12, a feed pump 16 and circulating pumps 13-15; wherein,

[0007] The starting inlet of the distillation column 1 is connected to the start-up steam pipeline, the running inlet is connected to the outlet of the steam saturator 6, the steam saturator 6 is connected to the third circulation pump 15, the inlet of the steam saturator 6 is connected to the outlet of the discharge flash steam compressor 2, the inlet of the discharge flash steam compressor 2 is connected to the outlet of the evaporation chamber of the discharge falling film evaporator 4; the shell-side non-condensable gas outlet of the discharge falling film evaporator 4 is connected to the shell-side inlet of the feed falling film evaporator 5; the outlet of the distillation column 1 and the outlet of the feed flash steam compressor 3 are combined and then connected to the shell-side inlet of the discharge falling film evaporator 4; the inlet of the feed flash steam compressor 3 is connected to the outlet of the evaporation chamber of the feed falling film evaporator 5, and the outlet of the feed flash steam compressor 3 and the outlet of the distillation column 1 are combined and then connected to the shell-side inlet of the discharge falling film evaporator 4.

[0008] The feed inlet of the distillation column 1 is connected to the liquid outlet of the tube side of the feed falling film evaporator 5 via a feed pump, and the discharge outlet is connected to the liquid inlet of the tube side of the discharge falling film evaporator 4.

[0009] The system feed inlet is simultaneously connected to the cold side air inlets of the first feed preheater 7, the second feed preheater 8, and the third feed preheater 9; the cold side discharge ends of the first feed preheater 7, the second feed preheater 8, and the third feed preheater 9 are connected to the feed inlet of the feed falling film evaporator 5.

[0010] The liquid outlet of the fourth shell side of the falling film evaporator is connected to the dilute ammonia water reflux tank.

[0011] In a preferred embodiment of the present invention, the discharge port of the discharge falling film evaporator 4 is connected to the discharge pump and then to the hot side inlet of the first feed preheater 7, so as to realize the heat exchange between the feed and the discharge through the heat exchange between the inlet and the outlet; the shell side non-condensable gas outlet of the feed falling film evaporator 5 is connected to the hot side inlet of the second feed preheater 8, so as to realize the heat exchange between the feed and the non-condensable gas through the heat exchange between the inlet and the outlet.

[0012] As a preferred embodiment of the present invention, the structure of the evaporator and evaporation chamber integrated falling film evaporator is used in the stripping and ammonia removal system.

[0013] In a preferred embodiment of the present invention, the third feed preheater 9 is provided with a dilute ammonia water pipeline, which is connected to the ammonia water return pump 11 and the dilute ammonia water return tank 10. The dilute ammonia water pipeline can exchange heat with the feed pipeline inside.

[0014] Secondly, embodiments of the present invention also provide an MVR stripping method for zero-steam wastewater ammonia removal, the method comprising the following steps:

[0015] When the device is started and preheated, fresh steam is introduced into the bottom of the rectification tower for system preheating, and after the system is normally operated, the secondary steam provided by the steam compressor can meet the process requirement of ammonia removal, and fresh steam provided by the outside is no longer needed.

[0016] The ammonia-containing wastewater is distributed and delivered by a pipeline to the first feed preheater and the second feed preheater, and after preheating, is introduced into the feed falling film evaporator pipe.

[0017] The feed wastewater is introduced into the liquid inlet of the rectification tower after being concentrated by the second circulating pump in the feed falling film evaporator; the shell side of the feed falling film evaporator inputs the non-condensable gas of the discharge falling film evaporator, and the pipe side gas is delivered into the feed flash steam compressor, and after being compressed, the ammonia-containing steam formed is combined with the steam output from the rectification tower and is input into the discharge falling film evaporator; the output shell side non-condensable gas is input into the second feed preheater; in the second feed preheater, the feed wastewater input on the cold side exchanges heat with the non-condensable gas delivered from the feed falling film evaporator on the hot side, and after the heat exchange is completed, the ammonia-containing non-condensable gas is output.

[0018] The steam from the gas outlet of the shell side of the discharge falling film evaporator is input into the discharge flash steam compressor, and after being compressed, is input into the rectification tower.

[0019] The ammonia in the wastewater is rectified by the rectification tower and is introduced into the discharge falling film evaporator shell side in the form of steam for heat utilization; the rectified wastewater is discharged and input into the pipe side of the discharge falling film evaporator, and after being concentrated by the first circulating pump in the discharge falling film evaporator, is input into the first feed preheater through the liquid outlet and the discharge pump; in the first feed preheater, the feed wastewater input on the cold side exchanges heat with the discharge wastewater delivered from the liquid outlet of the pipe side of the discharge falling film evaporator on the hot side; after the heat exchange is completed, the ammonia-removed wastewater is output.

[0020] The dilute ammonia water in the discharge falling film evaporator is input into the dilute ammonia water reflux tank from the lower side of the shell side, and a part of the dilute ammonia water is combined with the feed pumped by the feed pump and is input into the rectification tower.

[0021] The technical scheme provided by the embodiment of the present application has the following beneficial effects:

[0022] Compared with the scheme of using one falling film evaporator in general MVR stripping, the MVR stripping system and method for zero-steam wastewater ammonia removal uses two falling film evaporators in series, more uses the latent heat of ammonia-containing steam, the heat utilization range is reduced from 94 DEG C to 85 DEG C, the feed flash and the discharge flash jointly act, more secondary steam is generated, the problem of insufficient secondary steam is solved, and the zero consumption of fresh steam is realized.

[0023] Of course, implementing any product or method of the present application does not necessarily require achieving all the advantages described above at the same time. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the accompanying drawings needed to be used in the embodiments description will be briefly introduced. Obviously, the accompanying drawings in the following description only represent some of the embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0025] Figure 1 is a structure schematic diagram of the MVR stripping system for zero-steam wastewater deamination described in the embodiments of the present application.

[0026] Legend of reference signs:

[0027] 1-rectifying column, 2-outlet flash steam compressor, 3-feeding flash steam compressor, 4-outlet falling film evaporator, 5-feeding falling film evaporator, 6-steam saturator, 7-first feeding preheater, 8-second feeding preheater, 9-third feeding preheater, 10-dilute ammonia water reflux tank, 11-ammonia water reflux pump, 12-outlet pump, 13-first circulating pump, 14-second circulating pump, 15-third circulating pump, 16-feeding pump. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0029] It should be noted that: similar reference signs and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present application, the terms "first", "second", "third", "fourth" and the like are only used to distinguish description, and cannot be understood as indicating or implying relative importance.

[0030] The present application aims at the problem of large steam consumption, high resource and energy cost in stripping method wastewater deamination, and proposes a zero-steam wastewater deamination MVR stripping method and system. By setting a rectifying column, an outlet flash steam compressor, a feeding flash steam compressor, an outlet falling film evaporator, a feeding falling film evaporator and pipelines between each link, zero steam consumption is realized, energy utilization rate is improved, and energy saving and emission reduction are achieved.

[0031] As Figure 1As shown, the zero-vapor wastewater ammonia removal MVR stripping system comprises a rectifying tower 1, a discharge flash vapor compressor 2, a feed flash vapor compressor 3, a discharge falling film evaporator 4, a feed falling film evaporator 5, a vapor saturator 6, a first feed preheater 7, a second feed preheater 8, a third feed preheater 9, a dilute ammonia water reflux tank 10, an ammonia water reflux pump 11, a discharge pump 12, a feed pump 16, and circulating pumps 13-15.

[0032] The rectifying tower 1 is connected with a start-up vapor pipeline, and the running vapor pipeline is connected with the outlet of the vapor saturator 6; the vapor saturator 6 is connected with the third circulating pump 15; the inlet of the vapor saturator 6 is connected with the outlet of the discharge flash vapor compressor 2; the inlet of the discharge flash vapor compressor 2 is connected with the outlet of the evaporation chamber of the discharge falling film evaporator 4; the non-condensable gas outlet of the shell side of the discharge falling film evaporator 4 is connected with the inlet of the shell side of the feed falling film evaporator 5; the outlet of the rectifying tower 1 is connected with the outlet of the feed flash vapor compressor 3, and the combined outlet is connected with the inlet of the shell side of the discharge falling film evaporator 4; the inlet of the feed flash vapor compressor 3 is connected with the outlet of the evaporation chamber of the feed falling film evaporator 5, and the outlet of the feed flash vapor compressor 3 is connected with the outlet of the rectifying tower 1, and the combined outlet is connected with the inlet of the shell side of the discharge falling film evaporator 4.

[0033] The feed inlet of the rectifying tower 1 is connected with the outlet of the tube side of the feed falling film evaporator 5 through the feed pump, and the discharge outlet is connected with the inlet of the tube side of the discharge falling film evaporator 4.

[0034] The system feed inlet is connected with the first feed preheater 7 and the second feed preheater 8; the outlets of the first feed preheater 7 and the second feed preheater 8 are connected with the feed inlet of the feed falling film evaporator 5.

[0035] The outlet of the discharge falling film evaporator 4 is connected with the discharge pump, and then connected with the hot side inlet of the first feed preheater 7, so that the heat exchange between the feed and the discharge is realized through the interwall heat exchange; the non-condensable gas outlet of the shell side of the feed falling film evaporator 5 is connected with the hot side inlet of the second feed preheater 8, so that the heat exchange between the feed and the non-condensable gas is realized through the interwall heat exchange.

[0036] The tube side liquid circulation pipe of the feed falling film evaporator 5 is connected with a pipeline, and the second circulating pump 14 is arranged in the pipeline to circulate the liquid in the tube side; the tube side liquid circulation pipe of the discharge falling film evaporator 4 is connected with a pipeline, and the first circulating pump 13 is arranged in the pipeline to circulate the liquid in the tube side; the shell side outlet of the discharge falling film evaporator 4 is connected with the dilute ammonia water reflux tank.

[0037] Preferably, the discharge falling film evaporator and / or the feed falling film evaporator adopt an upper and lower integrated device structure of the evaporator and the evaporation chamber, so that the space is saved and the land occupation is reduced as much as possible under the premise of ensuring the evaporation and concentration effect.

[0038] Preferably, in order to realize the stability of the rectification tower inlet, especially the bottom tray, the outlet of the discharge steam compressor can further comprise a steam saturator 6, and the saturated steam enters the rectification tower kettle part for stripping and ammonia removal. At this time, the operation inlet of the rectification tower 1 is communicated with the outlet of the steam saturator 6, the steam saturator 6 is communicated with the third circulating pump 15, and the inlet of the steam saturator 6 is communicated with the outlet of the discharge flash steam compressor 2.

[0039] Preferably, considering the ammonia water concentration control requirement, the system of the embodiment can further comprise a dilute ammonia water discharge to a third feed preheater, and the obtained low-temperature ammonia water is used for the subsequent absorption liquid of the ammonia water recovery system, and part of the reflux can reduce the load of the ammonia removal tower and reduce the energy consumption. The third feed preheater 9 is internally provided with a dilute ammonia water pipeline, the dilute ammonia water pipeline is communicated with the ammonia water reflux pump 11 and the dilute ammonia water reflux tank 10, and the dilute ammonia water pipeline and the internal feed pipeline can be heat exchanged. At this time, the system feed inlet is simultaneously communicated with the first feed preheater 7, the second feed preheater 8 and the third feed preheater 9; the discharge ends of the first feed preheater 7, the second feed preheater 8 and the third feed preheater 9 are communicated with the feed inlet of the feed falling film evaporator 5.

[0040] When the zero-steam wastewater ammonia removal MVR stripping system is used for wastewater ammonia removal, the steam at the outlet of the discharge flash steam compressor is saturated after passing through the saturator, and steam is provided for the kettle of the rectification tower. The overhead steam of the rectification tower and the outlet steam of the feed flash steam compressor provide heat for the discharge falling film evaporator, play a major role in the self-sufficient system of steam, realize the purpose of material rectification, the feed flash steam compressor performs secondary utilization of the non-condensable steam heat, solves the problem of insufficient heat recovery, plays a supplementary role in the self-sufficient system of steam, compared with the general MVR stripping scheme using one falling film evaporator, the present application uses two falling film evaporator shells in series, more uses the latent heat of ammonia-containing steam, the heat utilization range is reduced from about 94 DEG C to about 85 DEG C, the feed flash and the discharge flash jointly act, generate more secondary steam, solve the problem of insufficient secondary steam, and realize zero consumption of fresh steam.

[0041] Based on the above system, the embodiment of the present application further provides a zero-steam wastewater ammonia removal MVR stripping method, which comprises the following steps:

[0042] When the device is preheated, fresh steam is introduced into the bottom of the rectification tower for system preheating. After the system is normally operated, the secondary steam provided by the steam compressor can meet the process requirements of ammonia removal, and fresh steam is no longer needed from the outside.

[0043] The wastewater containing ammonia is distributed and transported to the first feed preheater, the second feed preheater and the third feed preheater through the pipeline, and after preheating, enters the feed falling film evaporator pipe.

[0044] The feed wastewater is circulated by the second circulating pump after concentration in the feed falling film evaporator, and then enters the liquid inlet of the rectification tower; the non-condensable gas in the shell side of the feed falling film evaporator is input into the non-condensable gas output from the falling film evaporator, and the gas in the tube side is transported into the feed flash steam compressor, and after compression, the ammonia-containing steam formed is combined with the steam output from the rectification tower and input into the falling film evaporator; the output shell side non-condensable gas enters the second feed preheater; in the second feed preheater, the feed wastewater entering the cold side exchanges heat with the non-condensable gas transported from the falling film evaporator entering the hot side, and after the heat exchange is completed, the ammonia-containing non-condensable gas is output.

[0045] The steam from the gas outlet of the shell side of the falling film evaporator is input into the falling flash steam compressor, and after compression, is input into the steam saturator; the steam in the steam saturator is evaporated and concentrated by the third circulating pump, and then is input into the rectification tower; the saturated steam has a stabilizing effect on the operation of the rectification tower.

[0046] The ammonia in the wastewater is rectified by the rectification tower, and then in the form of steam enters the shell side of the falling film evaporator for heat utilization; the rectified wastewater is output and enters the tube side of the falling film evaporator, and after circulation and concentration in the falling film evaporator by the first circulating pump, is input into the first feed preheater through the liquid outlet and the discharge pump; in the first feed preheater, the feed wastewater entering the cold side exchanges heat with the discharged wastewater transported from the liquid outlet of the tube side of the falling film evaporator entering the hot side; after the heat exchange is completed, the deamination wastewater is output; thereby, two-stage energy utilization is performed on the tower discharge, which is the heat recovery of the falling film evaporator flash steam and the first feed preheater, respectively, achieving the effect of low-temperature discharge of the wastewater and fully recovering the energy.

[0047] In this step, the ammonia-containing steam at the top of the rectification tower is rectified, and then in the form of steam enters the shell side of the falling film evaporator for heat utilization, which is three-stage energy utilization of the falling film evaporator, the feed falling film evaporator and the second feed preheater, respectively, the energy is reasonably divided, the preheating recovery is sufficient, the falling film evaporator is provided with steam supplement by the feed flash steam compressor, the system energy consumption is further reduced, and MVR stripping deamination zero steam consumption is realized.

[0048] The dilute ammonia water in the falling film evaporator enters the dilute ammonia water reflux tank from the lower side of the shell side, a part of which is combined with the feed input by the feed pump by the dilute ammonia water reflux pump and input into the rectification tower, and the other part is pumped into the third feed preheater; in the third feed preheater, the feed wastewater entering the cold side exchanges heat with the dilute ammonia water entering the hot side, and after the exchange is completed, the dilute ammonia water is output.

[0049] When the above method is used for wastewater ammonia removal, the external material conveying equipment preheats the wastewater containing ammonia to 85 DEG C through three preheaters, the ammonia concentration in the wastewater is 1% at this point, the feed wastewater is fed into the feed falling film evaporator inlet, the material evaporated by circulation is pumped into the top of the rectification tower by the feed pump for ammonia removal, the tower top temperature is 100 DEG C, and the pressure is slightly positive. The evaporation control tube temperature of the feed falling film evaporator is 80 DEG C, the secondary steam generated is heated to 100 DEG C (saturation temperature) by the discharge flash steam compressor, and then is sprayed to be cooled to saturation and combined with the steam at the top of the rectification tower to be sent to the shell side of the discharge falling film evaporator for heating to discharge the tower bottom to generate secondary steam, the control tube temperature of the discharge falling film evaporator is 90 DEG C, the secondary steam generated is heated to 117 DEG C (saturation temperature) by the discharge flash steam compressor and is sent to the tower bottom of the rectification tower, and this steam can remove the ammonia in the wastewater in the tower bottom to 8 ppm. The wastewater at the tower bottom at 117 DEG C is flashed to recover heat in the discharge falling film evaporator, and then is discharged after further cooling in the feed preheater I.

[0050] According to the conditions of 55 t of wastewater at normal temperature, the flow rate of the feed flash steam compressor is 1.3 t / h, the heat recovered by the discharge falling film evaporator is transferred to the discharge after the heat recovery, the steam flow rate of the discharge flash steam compressor is 6.4 t / h, and fresh steam is not consumed, so that the ammonia content in the discharge can reach 8 ppm.

[0051] As can be seen, the MVR stripping system and method for zero-steam wastewater ammonia removal provided by the embodiment of the present application can achieve the purpose of steam self-sufficiency of the ammonia removal system, does not consume fresh steam supplied from outside, improves the energy utilization rate, achieves energy saving and emission reduction, avoids the consumption of a large amount of steam in the stripping process of the existing equipment, and reduces the wastewater discharge temperature.

[0052] The above description is merely preferred embodiments of the present application and a description of the principles of the technology used, and is not intended to limit the scope of the claimed present application, but merely represents the preferred embodiments of the present application. Those skilled in the art should understand that the scope of the application involved in the present application is not limited to the technical solutions formed by the specific combinations of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or equivalent features without departing from the inventive concept. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

Claims

1. A zero vapor wastewater deaminating MVR stripping system, characterized in that, The system comprises a rectifying tower (1), a discharge flash evaporation steam compressor (2), a feed flash evaporation steam compressor (3), a discharge falling film evaporator (4), a feed falling film evaporator (5), a steam saturator (6), a first feed preheater (7), a second feed preheater (8), a third feed preheater (9), a dilute ammonia water reflux tank (10), an ammonia water reflux pump (11), a discharge pump (12), a feed pump (16) and circulating pumps (13-15); wherein, The starting gas inlet of the rectifying tower (1) is communicated with a starting steam pipeline, the running gas inlet is communicated with the gas outlet of the steam saturator (6), the steam saturator (6) is communicated with the third circulating pump (15), the gas inlet of the steam saturator (6) is communicated with the gas outlet of the discharge flash evaporation steam compressor (2), the gas inlet of the discharge flash evaporation steam compressor (2) is communicated with the evaporation chamber gas outlet of the discharge falling film evaporator (4), the non-condensable gas outlet of the shell side of the discharge falling film evaporator (4) is communicated with the gas inlet of the shell side of the feed falling film evaporator (5), the gas outlet of the rectifying tower (1) is communicated with the gas outlet of the feed flash evaporation steam compressor (3) and then with the shell side gas inlet of the discharge falling film evaporator (4), the gas inlet of the feed flash evaporation steam compressor (3) is communicated with the evaporation chamber gas outlet of the feed falling film evaporator (5), the gas outlet of the feed flash evaporation steam compressor (3) is communicated with the gas outlet of the rectifying tower (1) and then with the shell side gas inlet of the discharge falling film evaporator (4), the feed inlet of the rectifying tower (1) is communicated with the tube side liquid outlet of the feed falling film evaporator (5) through the feed pump, and the discharge outlet is communicated with the tube side liquid inlet of the discharge falling film evaporator (4); The system feed inlet is communicated with the cold side gas inlets of the first feed preheater (7), the second feed preheater (8) and the third feed preheater (9), and the cold discharge ends of the first feed preheater (7), the second feed preheater (8) and the third feed preheater (9) are communicated with the feed inlet of the feed falling film evaporator (5); The shell side liquid outlet of the discharge falling film evaporator (4) is communicated with the dilute ammonia water reflux tank, the discharge outlet of the discharge falling film evaporator (4) is communicated with the first feed preheater (7) through the discharge pump, heat exchange is realized through the interwall heat exchange, and the feed and the discharge are heat-exchanged; the non-condensable gas outlet of the shell side of the feed falling film evaporator (5) is communicated with the hot side inlet of the second feed preheater (8), heat exchange is realized through the interwall heat exchange, and the feed and the non-condensable gas are heat-exchanged.

2. The zero vapor wastewater deaminating MVR stripping system of claim 1, wherein, The evaporation chamber and the evaporation chamber upper and lower integrated falling film evaporator device structure form are used in the stripping and deamination system.

3. The zero vapor wastewater deaminating MVR stripping system of claim 1, wherein, The third feed preheater (9) is internally provided with a dilute ammonia water pipeline, the dilute ammonia water pipeline is communicated with the ammonia water reflux pump (11) and the dilute ammonia water reflux tank (10), and the dilute ammonia water pipeline and the internal feed pipeline can be heat-exchanged.

4. A zero vapor wastewater deaminating MVR stripping process characterized by, The method comprises the following steps: When the device is preheated, fresh steam is introduced into the bottom of the rectifying tower to preheat the system, after the system is normally operated, the secondary steam provided by the steam compressor can meet the process requirement of deamination, and fresh steam provided by the outside is not needed any more; The wastewater containing ammonia is distributed and delivered to the first feed preheater and the second feed preheater through a pipeline, and after preheating, the wastewater is introduced into the tube side of the feed falling film evaporator; The feed wastewater is circulated by the second circulating pump in the feed falling film evaporator, and then enters the liquid inlet of the rectifying tower after concentration; the non-condensable gas in the shell side of the feed falling film evaporator is input into the output falling film evaporator, and the gas in the tube side is transported into the feed flash steam compressor, and after compression, the ammonia-containing steam formed is combined with the steam output from the rectifying tower and input into the output falling film evaporator; the output shell side non-condensable gas enters the second feed preheater; in the second feed preheater, the feed wastewater entering the cold side exchanges heat with the non-condensable gas transported from the feed falling film evaporator entering the hot side, and after heat exchange, ammonia-containing non-condensable gas is output; The steam from the shell side gas outlet of the output falling film evaporator is input into the output flash steam compressor, and after compression, is input into the rectifying tower; The ammonia in the wastewater is rectified by the rectifying tower, and then in the form of steam enters the shell side of the output falling film evaporator for heat utilization; the rectified wastewater is output and enters the tube side of the output falling film evaporator, and after circulation and concentration by the first circulating pump in the output falling film evaporator, is output through the liquid outlet and the output pump and then enters the first feed preheater; in the first feed preheater, the feed wastewater entering the cold side exchanges heat with the output wastewater transported from the liquid outlet of the tube side of the output falling film evaporator entering the hot side; After heat exchange, ammonia-removed wastewater is output; The dilute ammonia water in the output falling film evaporator enters the dilute ammonia water reflux tank from the lower side of the shell side, and a part is combined with the feed pumped by the feed pump and input into the rectifying tower by the dilute ammonia water reflux pump.

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