CN105480989B - Method for producing sodium hydroxide solution with concentration of 48% under low-pressure steam - Google Patents
Method for producing sodium hydroxide solution with concentration of 48% under low-pressure steam Download PDFInfo
- Publication number
- CN105480989B CN105480989B CN201510960824.8A CN201510960824A CN105480989B CN 105480989 B CN105480989 B CN 105480989B CN 201510960824 A CN201510960824 A CN 201510960824A CN 105480989 B CN105480989 B CN 105480989B
- Authority
- CN
- China
- Prior art keywords
- film evaporator
- effect
- falling film
- sodium hydroxide
- hydroxide solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D1/00—Oxides or hydroxides of sodium, potassium or alkali metals in general
- C01D1/04—Hydroxides
- C01D1/42—Concentration; Dehydration
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
- Cosmetics (AREA)
Abstract
The invention belongs to the field of the chlorine and alkali chemical industry, particularly relates to a method for producing a sodium hydroxide solution with the concentration of 48% under low-pressure steam, and aims at providing a rising-film evaporator used in cooperation with a double-effect backward-feed falling-film evaporation technology when external steam pressure is as low as 0.4-0.5 Mpa.G, and the sodium hydroxide solution with the concentration of 48% is prepared. When the pressure of an external steam heat source is as low as 0.4-0.5 Mpa.G, the sodium hydroxide solution with the concentration of 48% can be prepared.
Description
Technical field
The invention belongs to chemical industry for making chlorine and alkali field, and in particular to a kind of 48% sodium hydroxide solution of being produced under low-pressure steam
Method.
Background technology
In ionic membrane method alkali-making process, evaporization process produces 42% alkali using traditional double-countercurrent falling film evaporation technology
With 48% alkali, concentrated evaporator 73% alkali of production.Its technological process (see accompanying drawing 1) can sketch and be：Come from electrowinning process
32% liquid caustic soda is concentrated into 38% under vacuum by pump pressurization (0.2878Mpa.G) into II effect downward film evaporator
(75.4 DEG C, -0.0867Mpa.G), alkali lye preheater is forced into (successively with from I 139 DEG C of evaporator of effect through II effect lye pump
48% alkali lye and I (171 DEG C) of steam condensate of effect preheating) be warming up to 131.6 DEG C after；I effect downward film evaporator is entered back into, is used
38% liquid caustic soda is concentrated into 48% (138.9 DEG C of temperature, pressure -0.0122Mpa.G) by the saturated vapor heating of 0.8Mpa.G, secondly
Secondary steam to II effect downward film evaporator makees heating medium；48% liquid caustic soda from I effect downward film evaporator is by two heat exchange
Device enters back into concentrated evaporator, and the 38% alkali lye heat exchange with 2nd effect evaporator out before this is cooled to 85 DEG C, is then steamed with dense effect
171 DEG C of the steam condensate of hair device is warming up to 138 DEG C and delivers to concentrated evaporator, is steamed with the saturation of 0.8Mpa.G under vacuum
Liquid caustic soda is concentrated into 73% by vapour heating.
48% alkali is a kind of conventional standard commodities alkali.Original steams the alkali of alkali technique productions 48% to be completed in I effect evaporator
, the premise of normal production is that steam pressure reaches 0.8Mpa.G and (requires that external steam pressure limit is in former technological design
0.7-1.0Mpa.G, normal value is 0.8Mpa.G).But in the case of steam deficiency, when steam pressure is less than 0.7Mpa.G, or even
During as little as 0.4Mpa.G, vapor (steam) temperature is low, and II effect and I two evaporators of effect for only relying on original alkali-making process system cannot be produced
48% alkali is obtained, 73% alkali cannot be more produced.
Learnt by consulting NaOH physicochemical constant, sodium hydroxide solution boiling point is reduced with the rising of vacuum.Often
48% alkali boiling point of pressure is 140 DEG C, and 48% alkali boiling point under vacuum 74kpa is 104 DEG C, under vacuum 80kpa 48%
Alkali boiling point is 98 DEG C.Because I effect falling film evaporator systems are tiny structure, it is considered as desirable by the inventor to utilize idle climbing film evaporator,
By improving vacuum, alkali lye boiling point is reduced, produce the purpose of 48% alkali under the conditions of low-pressure steam to reach.
The content of the invention
The defective workmanship of 48% alkali presence is produced during for existing low-pressure steam, it is low that the present invention proposes external steam pressure
During to 0.4~0.5Mpa.G, using concentrated evaporator (i.e. climbing film evaporator), vacuum is improved, the method for preparing 48% alkali.Just
Step process flow is：Electrolysis liquid caustic soda → II imitates → I effect → dense effect.The technique steams the economic benefits and social benefits that former II effects and I effects prepare 48% alkali
Hair technique is changed to triple effect evaporation technique, makes full use of the flash principle of concentrated evaporator, not only reasonably distributes operating load,
The load that I imitates falling film evaporator is reduced, has also been reached under low-pressure steam, can equally produce the purpose of 48% alkali.
Problem to be solved by this invention is to provide under a kind of low-pressure steam the method for producing 48% sodium hydroxide solution.Should
Method is comprised the following steps：As external steam pressure as little as 0.4~0.5Mpa.G, in the technique of double-countercurrent falling film evaporation
On again use cooperatively climbing film evaporator, so as to prepare 48% sodium hydroxide solution.
Specifically, the method for the sodium hydroxide solution of above-mentioned production 48%, comprises the following steps：Electrowinning process is prepared
Alkali lye add II to imitate falling film evaporator, the vacuum of falling film evaporator is imitated in control II and heating make spent liquor evaporation to 36~
38wt%, temperature are 72~75 DEG C；Then I is added to imitate falling film evaporator after the alkali lye is heated again, falling film evaporator is imitated in control I
Vacuum and heat make spent liquor evaporation to 40~42wt%, temperature be 124~130 DEG C；Finally the alkali lye is added and rises film steaming
Hair device, controls the vacuum of climbing film evaporator and heating makes spent liquor evaporation to 48wt%.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the control II is imitated falling film evaporator, rises film steaming
The vacuum for sending out device is 76~80kpa.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the heating during II effect is by I effect falling liquid film
The indirect steam of evaporator is realized.
Preferably, it is I into the heating before I effect falling film evaporator in the method for the sodium hydroxide solution of above-mentioned production 48%
What the steam condensate (SC) obtained by effect resistance vapour sump pit was realized.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, I effect falling film evaporator and II imitates falling film evaporator
Connection, the vacuum of I effect falling film evaporator is realized by the vacuum of the effect falling film evaporator of control II.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the heating during I effect is by adding 0.4
What the external steam thermal source of~0.5Mpa.G was realized.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the heating during climbing-film evaporation is by adding
Enter the external steam thermal source realization of 0.4~0.5Mpa.G.
The inventive method controls rational parameter by reasonably combining falling film evaporator and climbing film evaporator
Condition, finally realizes the purpose that 48% alkali is prepared in outside steam source as little as 0.4~0.5Mpa.G.The present invention has
Simple to operate, low cost and other advantages.
Brief description of the drawings
The liquid caustic soda of Fig. 1 embodiments 1 and steam flow schematic diagram；
The former economic benefits and social benefits falling film evaporation technology flow chart of Fig. 2 embodiments 1；Parts, position and numbering in figure：Electrolytic lye 1,
Raw steam 2, I effect evaporator 3, I effect separator 4, I effect resistance vapour sump pit 5, E0303 I is imitated one section of heat exchanger 6, I and imitates two sections of heat exchange
Device 7, I effect lye pump 8, II effect evaporator 9, II effect separator 10, II effect resistance vapour sump pit 11, II effect lye pump 12, surface is cold
Condenser 13, vavuum pump 14, dense effect condenser 15, dense effect vavuum pump 16, concentrated evaporator 17, dense effect resistance vapour sump pit 18, dense effect
Heat exchanger 19, condensation liquid bath 20, salkali waste groove 21；
Fig. 3 is to the evaporation technology flow chart after the process modification of embodiment 1；Parts, position and numbering in figure：Electrolytic alkali
Liquid 1, raw steam 2, I effect evaporator 3, I effect separator 4, I effect resistance vapour sump pit 5, E0303 I are imitated one section of heat exchanger 6, I and imitate two sections
Heat exchanger 7, I effect lye pump 8, II effect evaporator 9, II effect separator 10, II effect resistance vapour sump pit 11, II effect lye pump 12, table
Face condenser 13, vavuum pump 14, dense effect condenser 15, dense effect vavuum pump 16, concentrated evaporator 17, dense effect resistance vapour sump pit 18,
Dense effect heat exchanger 19, condensation liquid bath 20, salkali waste groove 21.
Specific embodiment
A kind of method that 48% sodium hydroxide solution is produced under low-pressure steam, comprises the following steps：When external steam pressure
During as little as 0.4~0.5Mpa.G, climbing film evaporator is used cooperatively again in the technique of double-countercurrent falling film evaporation, so as to be prepared into
To 48% sodium hydroxide solution.
Specifically, the method for the sodium hydroxide solution of above-mentioned production 48%, comprises the following steps：Electrowinning process is prepared
Alkali lye add II to imitate falling film evaporator, the vacuum of falling film evaporator is imitated in control II and heating make spent liquor evaporation to 36~
38wt%, temperature are 72~75 DEG C；Then I is added to imitate falling film evaporator after the alkali lye is heated again, falling film evaporator is imitated in control I
Vacuum and heat make spent liquor evaporation to 40~42wt%, temperature be 124~130 DEG C；Finally the alkali lye is added and rises film steaming
Hair device, controls the vacuum of climbing film evaporator and heating makes spent liquor evaporation to 48wt%.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the control II is imitated falling film evaporator, rises film steaming
The vacuum for sending out device is 76~80kpa.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the heating during II effect is evaporated by I effect
The indirect steam of device is realized.
Preferably, it is I into the heating before I effect falling film evaporator in the method for the sodium hydroxide solution of above-mentioned production 48%
What the steam condensate (SC) obtained by effect resistance vapour sump pit was realized.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, I effect falling film evaporator and II imitates falling film evaporator
Connection, the vacuum of I effect falling film evaporator is realized by the vacuum of the effect falling film evaporator of control II.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the heating during I effect is by adding 0.4
What the external steam thermal source of~0.5Mpa.G was realized.
Preferably, in the method for the sodium hydroxide solution of above-mentioned production 48%, the heating during climbing-film evaporation is by adding
Enter the external steam thermal source realization of 0.4~0.5Mpa.G.
Concentrated evaporator described in the inventive method is climbing film evaporator.
Of the present invention 42%, 48% alkali is the commercially available alkali of different size, 42% alkali requirement alkali lye mass fraction >=
42%, 48% alkali then requires alkali lye mass fraction >=48%, and remaining index request refers to the industrial NaOH-liquid of GB 209
Body NaOH indexs.
The embodiment of the present invention be reach the object of the invention a kind of specific means, and the present invention be not only only limited to it is this kind of
Mode.
Embodiment 1
Fig. 1 is, in former economic benefits and social benefits falling film evaporation technology flow chart, certain change to be carried out on the basis of the technological process, with
The purpose of triple effect evaporation of the present invention is reached, the thick line portion seen in Fig. 2 is specifically transformed.I section of preheater and dense effect heat exchanger are imitated by I
Bypassed, in the case of steam deficiency, both can be avoided to lower the temperature alkali lye, effectively improved alkali liquid temperature.Actual production
In the steam load of falling film evaporator and concentrated evaporator can be imitated by regulation I, the alkali lye into concentrated evaporator can be improved
Temperature, dense effect vavuum pump control pressure, so that in outside steam pressure as little as 0.4~0.5Mpa.G, the device can also give birth to
The alkali lye of output 48%.
Alkali lye (30.65wt%, 80 DEG C) prepared by electrowinning process adds II to imitate falling film evaporator (control vacuum
Alkali lye (37.43%) is obtained after 78kpa)；(thermal source is for alkali lye heating：Steam condensate (SC) in I effect evaporator resistance vapour sump pits,
Temperature has 143-145 DEG C) (I effect evaporators use the external steam of 0.4Mpa.G to imitate falling film evaporator into I afterwards；System
Interior vacuum be 12.2kpa, vacuum ranges 0-15kpa) after obtain alkali lye (42.74wt%, 127 DEG C)；The alkali lye is added
Obtained after concentrated evaporator (i.e. climbing film evaporator) (controlling vacuum for 78kpa, to use the external steam of 0.4Mpa.G)
Alkali lye (48.54wt%, 102 DEG C)；Thermal source during II effect is provided by the indirect steam that I effect is evaporated.
By theoretical calculation original double-countercurrent falling film evaporation technology and triple effect evaporation technique of the invention steam water and
Load such as table 1 below：
Table 1
If as it can be seen from table 11 ton 30% of liquid caustic soda, during using former 48% alkali of technique productions, steams water ratio：Ⅱ
Effect 43.69%, I effect 56.31%；48% alkali is produced using present invention process, water ratio is steamed：II effect 43.69%, I effect
33.41%, dense effect 22.89%；Understand that present invention process reduces the operating load 40% of I effect evaporator, steam by contrast
Also more rationally, dense effect load is minimum, to outside steam pressure also step-down for pro rate.
Claims (5)
1. a kind of method that 48% sodium hydroxide solution is produced under low-pressure steam, it is characterised in that：When external steam pressure as little as
During 0.4~0.5Mpa.G, climbing film evaporator is used cooperatively again in the technique of double-countercurrent falling film evaporation, so as to prepare
48wt% sodium hydroxide solutions；
Concrete operations are：The alkali lye that electrowinning process is prepared adds II to imitate falling film evaporator, and falling film evaporator is imitated in control II
Vacuum and heat make spent liquor evaporation to 36~38wt%, temperature be 72~75 DEG C；Then I is added after the alkali lye is heated again
Effect falling film evaporator, controls the vacuum of I effect falling film evaporator and heats to make spent liquor evaporation to 40~42wt%, temperature be 124
~130 DEG C；The alkali lye is finally added into climbing film evaporator, the vacuum of climbing film evaporator is controlled and heating is made spent liquor evaporation extremely
48wt%；Heating during I effect is by adding what the external steam thermal source of 0.4~0.5Mpa.G was realized；Film is risen to steam
Heating during hair is by adding what the external steam thermal source of 0.4~0.5Mpa.G was realized.
2. the method that 48% sodium hydroxide solution is produced under low-pressure steam according to claim 1, it is characterised in that：It is described
Control II is imitated falling film evaporator, the vacuum of climbing film evaporator and is 76~80kpa.
3. the method that 48% sodium hydroxide solution is produced under low-pressure steam according to claim 1, it is characterised in that：II effect
During heating be to be realized by the indirect steam of I effect falling film evaporator.
4. the method that 48% sodium hydroxide solution is produced under low-pressure steam according to claim 1, it is characterised in that：Into
Heating before I effect falling film evaporator is that the steam condensate (SC) obtained by I effect resistance vapour sump pit is realized.
5. the method that 48% sodium hydroxide solution is produced under low-pressure steam according to claim 1, it is characterised in that：I effect
Falling film evaporator is connected with II effect falling film evaporator, and the vacuum of I effect falling film evaporator is to imitate falling film evaporator by control II
Vacuum realize.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510960824.8A CN105480989B (en) | 2015-12-18 | 2015-12-18 | Method for producing sodium hydroxide solution with concentration of 48% under low-pressure steam |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510960824.8A CN105480989B (en) | 2015-12-18 | 2015-12-18 | Method for producing sodium hydroxide solution with concentration of 48% under low-pressure steam |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105480989A CN105480989A (en) | 2016-04-13 |
| CN105480989B true CN105480989B (en) | 2017-05-17 |
Family
ID=55668324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510960824.8A Active CN105480989B (en) | 2015-12-18 | 2015-12-18 | Method for producing sodium hydroxide solution with concentration of 48% under low-pressure steam |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105480989B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112225229B (en) * | 2020-10-21 | 2023-04-07 | 华融化学股份有限公司 | Method for preparing high-purity potassium hydroxide solution by microwave heating and concentration |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101195493A (en) * | 2007-12-20 | 2008-06-11 | 金川集团有限公司 | Method for producing flake caustic |
| CN102303876A (en) * | 2011-05-24 | 2012-01-04 | 天辰化工有限公司 | Method for mixed burning of natural gas and calcium carbide furnace gas |
| CN102285670B (en) * | 2011-06-16 | 2013-07-10 | 肖正群 | Method and device for performing alkali concentration by utilizing synthesis waste heat of hydrogen chloride |
| CN102976362A (en) * | 2011-09-02 | 2013-03-20 | 韩扶军 | Novel alkali decoction device |
| CN103224243A (en) * | 2013-05-06 | 2013-07-31 | 张健 | Continuous production method of liquid alkali and falling-film evaporator |
-
2015
- 2015-12-18 CN CN201510960824.8A patent/CN105480989B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN105480989A (en) | 2016-04-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104355471B (en) | A kind of hotting mask coupling seawater desalination system and technique | |
| CN103949074B (en) | The method of a kind of titanium liquid concentration and device thereof | |
| CN101544437A (en) | Process method for recovering ammonium chloride and sodium chloride from waste water containing ammonium chloride and sodium chloride | |
| CN102225240B (en) | Concentration method based on combination of titanium liquid film evaporation and multilevel flash evaporation | |
| CN102344125A (en) | Technology for concentrating dilute sulfuric acid with multi-effect evaporation | |
| CN103922529B (en) | Low-energy-consumption device for recycling hydrochloric acid waste water and method for recycling hydrochloric acid waste water | |
| CN105536277B (en) | A kind of evaporating and concentrating process and device of the cellulose solvent NMMO aqueous solution | |
| CN105056565A (en) | Device and method for evaporation and crystallization of sodium gluconate solution | |
| CN108358176A (en) | A kind of dilute sulfuric acid vacuum concentrating apparatus and method | |
| CN105480989B (en) | Method for producing sodium hydroxide solution with concentration of 48% under low-pressure steam | |
| CN100556811C (en) | A kind of production method of low-salt dense soda ash and the system that produces low-salt dense soda ash thereof | |
| CN104986815B (en) | Universal evaporation concentration system experimental provision based on heat pump and climbing-film evaporation principle | |
| CN104649498A (en) | Desulfurization wastewater evaporation technology and system | |
| CN204840972U (en) | Doublestage MVR evaporimeter | |
| CN102774816B (en) | Method and device for concentrating waste acid in titanium dioxide production by sulfuric acid process | |
| CN102515201B (en) | Method and device for recycling waste clear liquid produced in process for producing sodium carbonate by ammonia-soda process | |
| CN103628085B (en) | Water resource circulation utilization method in chlor-alkali production | |
| CN204529575U (en) | A kind of desulfurization wastewater vapo(u)rization system | |
| CN104803538B (en) | A kind of low cost, low energy consumption process the process of sea water | |
| CN203593633U (en) | Energy-saving salt and nitre co-production device | |
| CN102145902A (en) | Method for producing high-quality potassium chloride | |
| CN106237642A (en) | A kind of industrial process saves the technology of energy consumption | |
| CN107867709A (en) | A kind of processing technology for being concentrated by evaporation aqueous sodium persulfate solution crystallization | |
| CN104771921B (en) | The collaborative energy-conservation unit of MVR of atmospheric pressure and energy-saving process | |
| CN103450001A (en) | Method and equipment for concentrating sodium formate in pentaerythritol production |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |