CN109458872A - A kind of liquid ammonia evaporator coil pipe cleaning device and cleaning method - Google Patents
A kind of liquid ammonia evaporator coil pipe cleaning device and cleaning method Download PDFInfo
- Publication number
- CN109458872A CN109458872A CN201811537345.5A CN201811537345A CN109458872A CN 109458872 A CN109458872 A CN 109458872A CN 201811537345 A CN201811537345 A CN 201811537345A CN 109458872 A CN109458872 A CN 109458872A
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- Prior art keywords
- nitrogen
- coil pipe
- evaporator coil
- liquid ammonia
- cleaning
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
- F28G9/00—Cleaning by flushing or washing, e.g. with chemical solvents
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
- Cleaning By Liquid Or Steam (AREA)
Abstract
A kind of liquid ammonia evaporator coil pipe cleaning device and cleaning method, the device includes the Nitrogen Control Units being connected with liquid ammonia evaporator coil pipe, cleaning control device and desalination water controller, the cleaning method of the liquid ammonia evaporator coil pipe purges 4 steps comprising ammonia displacement, cleaning solution cleaning, cleaning solution displacement, nitrogen；After being cleaned by using the cleaning device and cleaning method to liquid ammonia evaporator coil pipe, the impurity in coil pipe can be thoroughly removed, guarantees the normal operation of liquid ammonia evaporator, the further safe operation for guaranteeing unit；The cleaning device and cleaning method are simple, quick, safe and environment-friendly, low in cost, and the blocking suitable for all coal-burning power plant's ammonia area liquid ammonia evaporator coil pipe is cleaned.
Description
Technical field
The present invention relates to the storage of thermal power plant's ammonia and preparation technical fields, and in particular to a kind of liquid ammonia evaporator coil pipe cleaning dress
It sets and cleaning method.
Background technique
The main method of power plant boiler denitrating flue gas is ammonia process SCR, and the technique is using ammonia as reducing agent.In entire technique
During, it is first liquefied ammonia to be made to be evaporated to ammonia first, is then sent to SCR region and diluent air mixes merga pass distribution grid
It sprays into the flue gas of SCR reactor upstream and carries out denitrating flue gas.Since liquefied ammonia typically contains the impurity such as the compound of tar, iron,
After liquefied ammonia gasifies in ammonia evaporator coil, meeting residual solids glue eventually leads to the change of coil pipe internal diameter after accumulating over a long period
It is small or even the phenomenon that block completely, influence the safe operation of unit.
For coil pipe clogging, currently used treating method is Disintegration overhaul or integral replacing liquid ammonia evaporator,
Cost of investment is high, long processing period.
Summary of the invention
In order to solve the above-mentioned problems of the prior art, the purpose of the present invention is to provide a kind of liquid ammonia evaporator coil pipes
Cleaning device and cleaning method, the cleaning device and cleaning method are simple, quick, safe and environment-friendly, low in cost, are suitable for institute
There is the blocking of ammonia area, coal-burning power plant liquid ammonia evaporator coil pipe to clean.
To achieve the above objectives, the present invention adopts the following technical scheme:
A kind of liquid ammonia evaporator coil pipe cleaning device, including the Nitrogen Control Units being connected with liquid ammonia evaporator coil pipe 4
1, cleaning control device 2 and desalination water controller 3；
The Nitrogen Control Units 1 include the nitrogen cylinder 1-1 connecting with 4 import of liquid ammonia evaporator coil pipe, are evaporated in liquefied ammonia
Nitrogen pressure reducing valve 1-2, nitrogen manual modulation valve 1-3, nitrogen stream are disposed on the pipeline that device coil pipe is connect with nitrogen cylinder 1-1
Meter 1-4 and nitrogen displacement inlet valve 1-5, Nitrogen Control Units 1 further include being successively set on the outlet of liquid ammonia evaporator coil pipe 4
Ammonia detector 1-6, oxygen detection instrument 1-7 and nitrogen displacement outlet valve 1-8 on pipeline；
The cleaning control device 2 includes being connected with 4 inlet and outlet of liquid ammonia evaporator coil pipe by cleaning solution circulation pipe 2-3
The liquor box 2-1 connect, the cleaning solution 2-2 being placed in liquor box 2-1 are arranged in pneumatic on cleaning solution circulation pipe 2-3 inducer
The rinse liquid outlet valve 2- on cleaning solution circulation pipe 2-3 outlet section is arranged in infusion pump 2-4 and filter washing water inlet valve 2-5
6；
The desalination water controller 3 include the sweet-water tank 3-1 being connect with 4 import of liquid ammonia evaporator coil pipe, setting exist
Desalination water pump 3-2, the demineralized water rinse inlet valve 3-3 and demineralized water flushing outlet valve 3-4 of the bottom sweet-water tank 3-1.
The formula of the cleaning solution 2-2 is tertiary sodium phosphate: surfactant: the mass ratio of high purity water are as follows: 10:0.5:
89.5。
The method that the liquid ammonia evaporator coil pipe cleaning device carries out the cleaning of liquid ammonia evaporator coil pipe, includes the following steps:
1) ammonia is replaced: being installed Nitrogen Control Units 1 in 4 inlet and outlet of liquid ammonia evaporator coil pipe, is successively opened nitrogen
Nitrogen cylinder 1-1, nitrogen pressure reducing valve 1-2, nitrogen manual modulation valve 1-3, nitrogen displacement inlet valve 1-5 in control device 1 and
Nitrogen displacement outlet valve 1-8 replaces the ammonia in liquid ammonia evaporator coil pipe 4；When ammonia detector 1-7 detects ammonia concentration
When < 35mg/L, ammonia is replaced in liquid ammonia evaporator coil pipe 4, removes Nitrogen Control Units 1；
2) cleaning solution cleans: cleaning control device 2 is installed in 4 inlet and outlet of liquid ammonia evaporator coil pipe, by cleaning solution 2-2
Liquor box 2-1 is injected, evaporator bath temperature is controlled at 90 DEG C, cleaning solution circulation pipe 2-3 is connected, cleaning solution is successively opened and enters
Mouth valve 2-5, pneumatic infusion pump 2-4, wash cycles 30min；Rinse liquid outlet valve 2-6 is opened, checks that waste liquid is limpid without bright
When aobvious impurity, cleaning terminates, and removes cleaning control device 2；
3) cleaning solution is replaced: being installed desalination water controller 3 in 4 import of liquid ammonia evaporator coil pipe, is successively opened demineralized water
Rinse inlet valve 3-3, demineralized water flushing outlet valve 3-4 and desalination water pump 3-2, until waste liquid is limpid without obvious impurity, and
When detecting pH value less than 9, cleaning solution replacement completion removes desalination water controller 3；
4) nitrogen purges: installing Nitrogen Control Units 1 in 4 inlet and outlet of liquid ammonia evaporator coil pipe, successively opens nitrogen
Nitrogen cylinder 1-1, nitrogen pressure reducing valve 1-2, nitrogen manual modulation valve 1-3, nitrogen displacement inlet valve 1-5 in control device 1 and
Nitrogen displacement outlet valve 1-8, purges liquid ammonia evaporator coil pipe 4；It is small that oxygen concentration is detected by oxygen detection instrument 1-8
After 2%, continue to purge 10min, nitrogen purging finishes, and tears Nitrogen Control Units 1 open.
Using pneumatic infusion pump 2-4 and cleaning solution 2-2, wash cycles are carried out to liquid ammonia evaporator coil pipe 4.
Compared to the prior art the present invention, has the advantages that
1) cleaning solution in the present invention is made of weak base tertiary sodium phosphate and a small amount of surfactant, and cleaning efficiency is high, to gold
Metal conduit does not damage.And cleaning fluid composition environmental protection, it is cheap；
2) present invention uses wash cycles, improves the utilization rate of cleaning solution；
3) cleaning method of the invention is simple, safe, and whole cost is low.
Detailed description of the invention
Fig. 1 is overall structure diagram of the invention.
Fig. 2 is nitrogen control cabinet system schematic.
Fig. 3 is cleaning control cabinet system schematic.
Fig. 4 is demineralized water control cabinet system schematic.
Specific embodiment
Below in conjunction with drawings and the specific embodiments, the present invention is described in further detail.
As shown in Figure 1, the present invention be a kind of liquid ammonia evaporator coil pipe cleaning device, including with 4 phase of liquid ammonia evaporator coil pipe
Nitrogen Control Units 1, cleaning control device 2, the desalination water controller 3 of connection.
As shown in Fig. 2, the Nitrogen Control Units 1 include the nitrogen cylinder 1-1 connecting with liquid ammonia evaporator coil pipe import,
Nitrogen pressure reducing valve 1-2, nitrogen manual modulation valve are disposed on the pipeline that liquid ammonia evaporator coil pipe 4 is connect with nitrogen cylinder 1-1
1-3, nitrogen stream meter 1-4 and nitrogen displacement inlet valve 1-5, Nitrogen Control Units 1 further include being successively set on liquefied ammonia evaporation
Ammonia detector 1-6, oxygen detection instrument 1-7 and nitrogen displacement outlet valve 1-8 on 4 export pipeline of device coil pipe.
Ammonia displacement.Nitrogen Control Units 1 are installed in 4 inlet and outlet of liquid ammonia evaporator coil pipe.Successively open nitrogen control
Nitrogen cylinder 1-1, nitrogen pressure reducing valve 1-2, nitrogen manual modulation valve 1-3, nitrogen displacement inlet valve 1-5 and nitrogen in device 1 processed
Gas displacement outlet valve 1-8 replaces the ammonia in liquid ammonia evaporator coil pipe 4.When ammonia detector 1-7 detects ammonia concentration <
When 35mg/L, ammonia is replaced in liquid ammonia evaporator coil pipe 4, removes Nitrogen Control Units 1.
Nitrogen purging.Nitrogen Control Units 1 are installed in 4 inlet and outlet of liquid ammonia evaporator coil pipe.Successively open nitrogen control
Nitrogen cylinder 1-1, nitrogen pressure reducing valve 1-2, nitrogen manual modulation valve 1-3, nitrogen displacement inlet valve 1-5 and nitrogen in device 1 processed
Gas displacement outlet valve 1-8, purges liquid ammonia evaporator coil pipe 4.Oxygen concentration is detected by oxygen detection instrument 1-8 to be less than
After 2%, continue to purge 10min, nitrogen purging finishes, and tears Nitrogen Control Units 1 open.
As shown in figure 3, the cleaning control device 2 includes passing through cleaning solution with 4 inlet and outlet of liquid ammonia evaporator coil pipe
The liquor box 2-1 of circulation pipe 2-3 connection, the cleaning solution 2-2 being placed in liquor box 2-1 are arranged in cleaning solution circulation pipe 2-3 import
Pneumatic infusion pump 2-4 and filter washing water inlet valve 2-5 in section, are arranged in the cleaning solution on cleaning solution circulation pipe 2-3 outlet section
Outlet valve 2-6.
Cleaning solution cleaning.Cleaning control device cabinet 2 is installed in 4 inlet and outlet of liquid ammonia evaporator coil pipe.By cleaning solution 2-2
Liquor box 2-1 is injected, the formula of the cleaning solution is tertiary sodium phosphate: surfactant: high purity water=10:0.5:89.5 (quality
Than).By evaporator bath temperature control at 90 DEG C, connect cleaning solution circulation pipe 2-3, successively open filter washing water inlet valve 2-5,
Pneumatic infusion pump 2-4, wash cycles 30min.Open rinse liquid outlet valve 2-6, check waste liquid it is limpid without obvious impurity when, clearly
End is washed, cleaning control device 2 is removed.
As shown in figure 4, the desalination water controller 3 includes the sweet-water tank connecting with 4 import of liquid ammonia evaporator coil pipe
3-1, the desalination water pump 3-2 that the bottom sweet-water tank 3-1 is set, demineralized water rinse inlet valve 3-3 and demineralized water flushing outlet
Valve 3-4.
Cleaning solution displacement.Desalination water controller 3 is installed in 4 import of liquid ammonia evaporator coil pipe.Successively open demineralized water punching
Inlet valve 3-3, demineralized water flushing outlet valve 3-4 and desalination water pump 3-2 are washed, until waste liquid is limpid without obvious impurity, and is examined
When surveying pH value less than 9, cleaning solution replacement completion removes desalination water controller 3.
Claims (3)
1. a kind of liquid ammonia evaporator coil pipe cleaning device, it is characterised in that: including the nitrogen being connected with liquid ammonia evaporator coil pipe (4)
Gas control device (1), cleaning control device (2) and desalination water controller (3)；
The Nitrogen Control Units (1) include the nitrogen cylinder (1-1) connecting with liquid ammonia evaporator coil pipe (4) import, are steamed in liquefied ammonia
Nitrogen pressure reducing valve (1-2), nitrogen manual modulation valve are disposed on the pipeline that hair device coil pipe (4) is connect with nitrogen cylinder (1-1)
(1-3), nitrogen stream meter (1-4) and nitrogen displacement inlet valve (1-5), Nitrogen Control Units (1) further include being successively set on
Ammonia detector (1-6), oxygen detection instrument (1-7) and nitrogen displacement outlet valve on liquid ammonia evaporator coil pipe (4) export pipeline
Door (1-8)；
The cleaning control device (2) includes passing through cleaning solution circulation pipe (2-3) with liquid ammonia evaporator coil pipe (4) inlet and outlet
The liquor box (2-1) of connection, the cleaning solution (2-2) being placed in liquor box (2-1) are arranged in cleaning solution circulation pipe (2-3) import
Pneumatic infusion pump (2-4) and filter washing water inlet valve (2-5) in section are arranged on cleaning solution circulation pipe (2-3) outlet section
Rinse liquid outlet valve (2-6)；
The desalination water controller (3) includes the sweet-water tank (3-1) connecting with liquid ammonia evaporator coil pipe (4) import, setting
In the desalination water pump (3-2) of the bottom sweet-water tank (3-1), demineralized water rinse inlet valve (3-3) and demineralized water flushing outlet valve
Door (3-4).
2. a kind of liquid ammonia evaporator coil pipe cleaning device according to claim 1, it is characterised in that: the cleaning solution (2-
2) formula is tertiary sodium phosphate: surfactant: the mass ratio of high purity water are as follows: 10:0.5:89.5.
3. the method that liquid ammonia evaporator coil pipe cleaning device described in claim 1 carries out the cleaning of liquid ammonia evaporator coil pipe, feature
It is: includes the following steps:
1) ammonia is replaced: being installed Nitrogen Control Units (1) in liquid ammonia evaporator coil pipe (4) inlet and outlet, is successively opened nitrogen
Nitrogen cylinder (1-1), nitrogen pressure reducing valve (1-2), nitrogen manual modulation valve (1-3), nitrogen displacement inlet valve in control device (1)
Door (1-5) and nitrogen displacement outlet valve (1-8) replace the ammonia in liquid ammonia evaporator coil pipe (4)；When ammonia detector
When (1-7) detects ammonia concentration < 35mg/L, ammonia is replaced in liquid ammonia evaporator coil pipe (4), removes Nitrogen Control Units
(1)；
2) cleaning solution cleans: cleaning control device (2) is installed in liquid ammonia evaporator coil pipe (4) inlet and outlet, by cleaning solution (2-
2) liquor box (2-1) is injected, evaporator bath temperature is controlled at 90 DEG C, is connected cleaning solution circulation pipe (2-3), successively opened clear
Wash liquor inlet valve (2-5), pneumatic infusion pump (2-4), wash cycles 30min；It opens rinse liquid outlet valve (2-6), checks
Waste liquid it is limpid without obvious impurity when, cleaning terminates, remove cleaning control device (2)；
3) cleaning solution is replaced: being installed desalination water controller (3) in (4) import of liquid ammonia evaporator coil pipe, is successively opened demineralized water
Rinse inlet valve (3-3), demineralized water flushing outlet valve (3-4) and desalination water pump (3-2), until the limpid nothing of waste liquid is obviously miscellaneous
Matter, and when detecting pH value less than 9, cleaning solution replacement completion is removed desalination water controller (3)；
4) nitrogen purges: installing Nitrogen Control Units (1) in liquid ammonia evaporator coil pipe (4) inlet and outlet, successively opens nitrogen
Nitrogen cylinder (1-1), nitrogen pressure reducing valve (1-2), nitrogen manual modulation valve (1-3), nitrogen displacement inlet valve in control device (1)
Door (1-5) and nitrogen displacement outlet valve (1-8), purge liquid ammonia evaporator coil pipe (4)；Pass through oxygen detection instrument (1-
8) after detection oxygen concentration is less than 2%, continue to purge 10min, nitrogen purging finishes, and tears Nitrogen Control Units (1) open.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811537345.5A CN109458872A (en) | 2018-12-15 | 2018-12-15 | A kind of liquid ammonia evaporator coil pipe cleaning device and cleaning method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811537345.5A CN109458872A (en) | 2018-12-15 | 2018-12-15 | A kind of liquid ammonia evaporator coil pipe cleaning device and cleaning method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109458872A true CN109458872A (en) | 2019-03-12 |
Family
ID=65613409
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811537345.5A Pending CN109458872A (en) | 2018-12-15 | 2018-12-15 | A kind of liquid ammonia evaporator coil pipe cleaning device and cleaning method |
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| CN (1) | CN109458872A (en) |
Citations (9)
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|---|---|---|---|---|
| CN1103336A (en) * | 1993-12-02 | 1995-06-07 | 朱几 | Method of chemically cleaning pipeline |
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| CN107441744A (en) * | 2017-09-16 | 2017-12-08 | 深圳市华琥技术有限公司 | The shuffling method and mixed washing apparatus of a kind of liquid ammonia evaporator |
| CN207816088U (en) * | 2018-01-02 | 2018-09-04 | 内蒙古大唐国际托克托发电有限责任公司 | A kind of liquid ammonia evaporator coil pipe cleaning device |
| CN108687066A (en) * | 2018-05-22 | 2018-10-23 | 西安西热水务环保有限公司 | A kind of reverse-flow multiple-effect evaporation condensing crystallizing device cleaning device |
| CN209445879U (en) * | 2018-12-15 | 2019-09-27 | 华能应城热电有限责任公司 | A kind of liquid ammonia evaporator coil pipe cleaning device |
-
2018
- 2018-12-15 CN CN201811537345.5A patent/CN109458872A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1103336A (en) * | 1993-12-02 | 1995-06-07 | 朱几 | Method of chemically cleaning pipeline |
| CN101038053A (en) * | 2006-12-29 | 2007-09-19 | 淳安千岛湖康盛制冷管路研究开发有限公司 | Pipe for connecting air conditioner and manufacturing method |
| CN102400167A (en) * | 2011-11-21 | 2012-04-04 | 河南中原黄金冶炼厂有限责任公司 | Chemical cleaning method for scales on tube of evaporator for producing ammonium sulfate |
| CN205580291U (en) * | 2016-05-04 | 2016-09-14 | 大唐韩城第二发电有限责任公司 | Plate heat exchanger from belt cleaning device |
| CN106694479A (en) * | 2017-01-09 | 2017-05-24 | 湖南华润电力鲤鱼江有限公司 | Cleaning method and device of mixed type liquid ammonia evaporator |
| CN107441744A (en) * | 2017-09-16 | 2017-12-08 | 深圳市华琥技术有限公司 | The shuffling method and mixed washing apparatus of a kind of liquid ammonia evaporator |
| CN207816088U (en) * | 2018-01-02 | 2018-09-04 | 内蒙古大唐国际托克托发电有限责任公司 | A kind of liquid ammonia evaporator coil pipe cleaning device |
| CN108687066A (en) * | 2018-05-22 | 2018-10-23 | 西安西热水务环保有限公司 | A kind of reverse-flow multiple-effect evaporation condensing crystallizing device cleaning device |
| CN209445879U (en) * | 2018-12-15 | 2019-09-27 | 华能应城热电有限责任公司 | A kind of liquid ammonia evaporator coil pipe cleaning device |
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