CN100389892C - Recovering treatment of hydrated hydrazine by-product saline-alkali by urea method - Google Patents
Recovering treatment of hydrated hydrazine by-product saline-alkali by urea method Download PDFInfo
- Publication number
- CN100389892C CN100389892C CNB2005100218591A CN200510021859A CN100389892C CN 100389892 C CN100389892 C CN 100389892C CN B2005100218591 A CNB2005100218591 A CN B2005100218591A CN 200510021859 A CN200510021859 A CN 200510021859A CN 100389892 C CN100389892 C CN 100389892C
- Authority
- CN
- China
- Prior art keywords
- alkali
- slurry
- hydrazine hydrate
- sodium carbonate
- caustic soda
- 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
Images
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The present invention discloses a method for recovering and treating byproducts in an evaporation process by producing hydrazine hydrate by the method of urea, sodium hypochlorite and sodium hydroxide oxidation. The present invention comprises a pulping step, a salt pulp and alkali pulp separating step, a treating step for salt pulp, a treating step for alkali pulp, and a mother liquid recycle pulping step. Because salt and alkali are separated in stages by being pulped with hot water, the present invention has the advantages of waste hot water discharge, high safety factor, energy conservation, easy operation, easy recovery of hydrazine hydrate, obviously advanced technology, etc. Monohydrated sodium carbonate with lower quality is treated by an incineration method, and calcined tail gas is absorbed by water so as to reduce the water content of sodium carbonate and the content of other impurities, improve the quality of recovered matter, increase the commodity value of the sodium carbonate, and simultaneously avoid the environment pollution caused by the calcined tail gas. The recovered solid salt is directly atomized into brine, and fine brine after treatment returns to an electric groove so as to truly realize the closed cycle production of a chlorine-alkali system.
Description
Technical field
The present invention relates to a kind of processing method of producing the accessory substance in the hydrazine hydrate process with urea, clorox, NaOH oxidizing process, more particularly, is the saline and alkaline method that recycles to institute's by-product in the evaporation process.
Background technology
Hydrazine hydrate has another name called: hydrazine hydrate, chemical formula: N
2H
4H
2O, molecular weight: 50.07, belong to fine chemical product.Hydrazine hydrate is as a kind of chemical intermediate, and its potential use and application are very extensive, mainly is divided into three aspects: one, produce plastics blowing agent; Its two, in the vapor recycle of power industry, it is used as and prevents that pipeline from getting rusty and aging in advance, thereby improves the security reliability in power station greatly; In addition, hydrazine hydrate also is important medicine and pesticide material.The various production methods of hydrazine hydrate, as draw west (Rashig) method, Bel's (Bayer) method or hydrogen peroxide method, the present invention is according to adopting urea, clorox, NaOH oxidizing process (abbreviation urea method), technological process is mainly as follows: with caustic soda, water, chlorine is raw material preparation liquor natrii hypochloritis, close the thick solution of hydrazine with the urea liquid water generation reaction, wherein contain sodium carbonate, sodium chloride, NaOH and water, the thick solution of hydrazine hydrate is through crystallisation by cooling, reclaim washing soda wherein, again solution is evaporated, water that evaporates and hydrazine hydrate steam carry out the hydrazine hydrate that rectifying obtains high-load again, the sodium carbonate of by-product in the evaporation process, sodium chloride and a small amount of hydrazine hydrate that is entrained with, saline and alkaline mixture such as NaOH and water.
The main chemical reactions equation of urea legal system hydrazine hydrate is:
Cl
2+2NaOH---NaClO+NaCl+H
2O
NaClO+N
2H
4CO+2NaOH---N
2H
4·H
2O+Na
2CO
3+NaCl
Its key reaction has two, and water generation reaction closes the thick solution of hydrazine, simultaneously by-product a large amount of sodium carbonate, sodium chloride, the chemical analysis of the saline and alkaline mixture that obtains after the hydrazine hydrate in the thick solution of hydrazine hydrate, the water evaporation is as follows:
Sodium chloride: 20-60% sodium carbonate: 10-35% caustic soda: 2-15%
N
2H
4H
2All the other 10-25% of O:0.2-1.0% are water and other trace impurity
As seen, there is following shortcoming in urea method production hydrazine hydrate method: the sodium chloride that stays in evaporation process, sodium carbonate, caustic soda, N
2H
4H
2O all has certain economic value, be unrealized in the past and reclaim entirely, such as Chinese patent 00120610.9 disclosed " a kind of method of separating the hydrazine hydrate alkali mud " and 01133711.7 disclosed " a kind of method of recycle-water hydrazine hydrate continuous distillation salt mud " and 02113204.6 disclosed " a kind of carbonization; the method for dried recovered hydrazine hydrate alkali mud ", these the three kinds methods of handling salt slurry all are that sodium chloride in the salt slurry and sodium carbonate are separated utilization, or caustic soda is converted into sodium carbonate recycles, but still exist the by-product recovery rate low, reclaim incomplete shortcoming, be difficult to realize that large-scale industry recycles, do not have the N that reclaims wherein as these methods
2H
4H
2O, directly enter in the rivers behind the dilute with water, caused the very big waste of resource, simultaneously, saline and alkaline mixture contains a certain amount of hydrazine hydrate and ammonia, if directly discharging,, be very serious to the pollution of environment because its ammonia nitrogen index exceeding standard reaches about 300--500 times (industrial wastewater qualified discharge ammonia nitrogen index is 15mg/l) and have higher basicity (pH value 〉=11).Therefore, how to realize that it is the technical problem that needs to be resolved hurrily in the current hydrazine hydrate production process to the pollution of environment that resource reclaims and make full use of, solves by-product saline-alkali entirely.
Summary of the invention
The present invention at first purpose is the separating and recovering processing method that provides a kind of urea method to produce the by-product saline-alkali that produces in the hydrazine hydrate process for addressing the above problem, can realize whole recyclings of accessory substance after using this method to the by-product saline-alkali separating treatment, the material that is discharged meets national requirements for environmental protection.
The object of the present invention is achieved like this:
(a) slurrying step: by-product saline-alkali in the urea method hydrazine hydrate reaction under stirring condition, is added temperature in 65-90 ℃ hot water, make solid-to-liquid ratio and be 0.3～0.8: 1 the slurries that contain sodium carbonate, sodium chloride, caustic soda, hydrazine hydrate.
(b) separating step of salt slurry and alkali slurry: (a) salt slurry that mainly contains sodium chloride and the alkali slurry that mainly contains sodium carbonate are arranged in the slurries that make in the step, utilize the gravity different mining of salt slurry and alkali slurry with classifying equipoment the salt slurry to be separated with the alkali slurry, obtaining solid-to-liquid ratio respectively is 0.6-1: 1 salt slurry and 0.3-0.6: 1 alkali slurry;
(c) treatment step of salt slurry: will be in (b) step isolated salt slurry after the centrifuge separation, obtain caustic soda content be 2～8% and sodium chloride content be 65～85% solid sodium chloride and mother liquor, the solid sodium chloride that obtains is configured to solution, adds between acid adjustment its pH value to 8～9 through adding water, being mixed with sodium chloride content is the refined brine of 200～300g/l, total ammonium content≤80ppm, send the chlor-alkali system as the raw material of producing chlorine and caustic soda this refined brine.
(d) treatment step of alkali slurry: will be in (b) step isolated alkali slurry to obtain carbonate content after the centrifuge separation be 45～65% monohydrated sodium carbonate and mother liquor, this monohydrated sodium carbonate sent in the rotary kiln under 150～500 ℃ of conditions calcine, calcination time was controlled at 1～5 hour, remove the moisture in the monohydrated sodium carbonate, obtain sodium carbonate through pulverizing behind caustic soda and other impurity, to calcine the tail gas that produces simultaneously absorbs with water circulation in the air exhauster suction absorption tower, tail gas absorbs the back emptying, and the absorption liquid that produces in the absorption tower send the sewage disposal collecting pit through behind the clarification filtration.
(e) mother liquor reuse slurrying step: two kinds of mother liquors that produce in the treatment step with the treatment step of salt slurry and alkali slurry separate the back remittance together by centrifuge, keeping delivering to the slurrying step under 60～90 ℃ of conditions, continuation as next time saline and alkaline mixture the slurrying medium and recycle, under stirring condition, in mother liquor, add by-product saline-alkali, when the solid-to-liquid ratio of slurries 0.3～0.8: 1, temperature configures slurries when being 80～95 ℃, no longer again, use hot water slurrying this moment, through behind the circulating pulp-making repeatedly, hydrazine hydrate in saline and alkaline and caustic soda constantly dissolve in the mother liquor, hydrazine hydrate rises to 5～15g/l in mother liquor, when caustic soda rises to 60～120g/l, with pump this mother liquor is returned vapo(u)rization system recovery hydrazine hydrate wherein, and the caustic soda that constantly consumes in the additional vapo(u)rization system.
The present invention has following advantage than prior art:
The present invention is because (1) adopts saline and alkaline with classification separation after the hot water slurrying, there is not successful precedent in the urea legal system hydrazine hydrate by-product saline-alkali recovery method both at home and abroad, this method is compared with adopting concentrated base or other medium slurrying, have solve spent hot water's discharging, safety coefficient height, energy savings, easy and simple to handle, reclaim advantage such as hydrazine hydrate easily, technical advance is obvious.And adopt concentrated base slurrying, have unsurmountable alkali consumption height, the big and centrifugal difficulty of hidden danger, slurry viscosity that concentrated base is hurted sb.'s feelings, too high basicity affects recovery shortcomings such as hydrazine hydrate wherein; (2) adopt method for calcinating to handle the lower monohydrated sodium carbonate of quality, and calcining tail gas is carried out water absorb, reduced moisture and other impurity content of sodium carbonate, improved the quality of regenerant, increased the commodity value of sodium carbonate, solved of the pollution of calcining tail gas simultaneously environment; (3) will reclaim solid salt and directly change into salt solution, and by washing, adding acid, obtain refined brine and return electric groove, and really realize chlor-alkali system lock circulation production, urea method is produced hydrazine hydrate technology and has been obtained qualitative leap.
Description of drawings
Fig. 1 is a technological process block-diagram of the present invention.
The specific embodiment
Below in conjunction with drawings and Examples the present invention is described in further detail, but the present invention has more than and is limited to these examples.
Step at first routinely prepares hydrazine hydrate, at first 30% caustic soda is put into the diluted alkaline make-up tank, is adding certain amount of industrial water, with pump constantly circulation to mix content be stand-by behind the 250-320g/l; Again industry water is put into urea liquid make-up tank, under agitation added solid urea and catalyst, treat that it is solution for later use behind the 250-320g/l that solid urea dissolves content; Then diluted alkaline is sent in the sodium hypochlorite reaction device by certain flow, fed chlorine, usefulness-5-5 ℃ of chilled brine cooling controlled reaction temperature and contained the liquor natrii hypochloritis that effective chlorine is 5-15% making below 30 ℃.Chemical equation:
2NaOH+Cl
2＝NaClO+NaCl+H
2O
With pump clorox and urea liquid are mixed the back by a certain percentage then and contain the thick solution of hydrazine hydrate, chemical equation to 100-110 ℃ of reaction generation with steam heated:
NaClO+N
2H4
CO+2NaOH＝N
2H
4·H
2O+Na
2CO
3+NaCl
The thick solution of hydrazine hydrate is cooled to＜sends in the crystallization kettle after 50 ℃ with pump then, with＜-5 ℃ liquefied ammonia or chilled brine cooling, after temperature was reduced to-2 ℃, centrifugation went out in the thick hydrazine hydrate solution 70% sodium carbonate.Send in the forced-circulation evaporator and evaporate removing the thick solution of hydrazine hydrate behind the sodium carbonate, water that evaporates and hydrazine hydrate steam enter again constantly carry in the rectifying column dense to 80%.The chemical analysis of the saline and alkaline mixture that obtains after the evaporation of the hydrazine hydrate in the thick solution of hydrazine hydrate, water is as follows:
Sodium chloride: 45% sodium carbonate: 25% caustic soda: 8% N
2H
4H
2O:1%
All the other 21% are water and other trace impurity.
Embodiment 1: above-mentioned saline and alkaline mixture is handled as follows:
(a) the slurrying step adopts hot water to carry out slurrying as the slurrying medium: be evacuated to 90 ℃ of hot water of discharging in the system in the pulping tank of band stirring with pump, open to stir and successively add hydrazine hydrate by-product saline-alkali mixture, made solid-to-liquid ratio and be 0.8: 1 and contained the supersaturation slurries of sodium carbonate, sodium chloride, caustic soda, hydrazine hydrate;
(b) separating step of salt slurry and alkali slurry: with pump the slurries that make in (a) step are squeezed into the suspension device and carry out classification, utilize the gravity different principle of salt slurry and alkali slurry that the salt slurry is separated with the alkali slurry, obtaining solid-to-liquid ratio respectively is 1: 1 salt slurry and 0.6: 1 alkali slurry;
(c) treatment step of salt slurry: contain following material in the mother liquor that the salt slurry that classification in (b) step is gone out obtains after centrifuge separates: content is the caustic soda of 50g/l, content is the sodium chloride of 200g/l, content is the sodium carbonate of 100g/l, content is the hydrazine hydrate of 5g/l, contain 8% caustic soda and 85% sodium chloride in the centrifugal solid sodium chloride that obtains, this solid sodium chloride is configured to solution through adding water, add hydrochloric acid neutralization caustic soda wherein again, adjusting pH value is 8～9, being mixed with sodium chloride content is 250g/l, the refined brine of total ammonium content≤80ppm send the chlor-alkali system as the raw material of producing chlorine and caustic soda this refined brine.
(d) treatment step of alkali slurry: alkali slurry that will classification goes out in (b) step obtains carbonate content after the centrifuge separation be 65% monohydrated sodium carbonate and mother liquor, this monohydrated sodium carbonate sent in the rotary kiln under 500 ℃ of conditions calcine, calcination time was controlled at 1 hour, remove the moisture in the monohydrated sodium carbonate, obtain sodium carbonate through pulverizing behind caustic soda and other impurity, to calcine the tail gas that produces simultaneously absorbs with water circulation in the air exhauster suction absorption tower, tail gas absorbs the back emptying, the absorption liquid that produces in the absorption tower send the sewage disposal collecting pit to handle through clear liquid behind the clarification filtration, and the water retrieval system of handling after qualified recycles;
(e) mother liquor reuse slurrying step: two kinds of mother liquors that produce in the treatment step with the treatment step of salt slurry and alkali slurry separate the back remittance together by centrifuge, keeping delivering to the slurrying step under 80 ℃ of conditions, continuation as next time saline and alkaline mixture the slurrying medium and recycle, under stirring condition, in mother liquor, add saline and alkaline, when the solid-to-liquid ratio of slurries at 0.8: 1, temperature configures slurries when being 90 ℃, no longer again, use hot water slurrying this moment, through behind the circulating pulp-making repeatedly, hydrazine hydrate in saline and alkaline and caustic soda constantly dissolve in the mother liquor, hydrazine hydrate content rises to 15g/l in mother liquor, when caustic soda content rises to 120g/l, with pump this mother liquor is returned vapo(u)rization system and distillation system and adopt that the conventional method evaporation is smart stays recovery hydrazine hydrate wherein, and the caustic soda that constantly consumes in the additional vapo(u)rization system.The mother liquor amount that reduces is replenished by the hot water that adds again, and mode of operation is the same.
Embodiment 2: prepare hydrazine hydrate according to above-mentioned conventional steps, the chemical analysis of the saline and alkaline mixture that obtains after the hydrazine hydrate in the thick solution with hydrazine hydrate, the water evaporation is as follows:
Sodium chloride: 30% sodium carbonate: 15% caustic soda: 10% N
2H
4H
2O:0.4%
All the other are water and other trace impurity.Above-mentioned saline and alkaline mixture is handled as follows:
(a) slurrying step: carry out slurrying as the slurrying medium: be evacuated to 65 ℃ of hot water of discharging in the system in the pulping tank of band stirring with pump with hot water, open to stir and successively add hydrazine hydrate by-product saline-alkali mixture, made solid-to-liquid ratio and be 0.3: 1 and contained the supersaturation slurries of sodium carbonate, sodium chloride, caustic soda, hydrazine hydrate;
(b) separating step of salt slurry and alkali slurry: with pump the slurries that make in (a) step are squeezed into the suspension device and carry out classification, utilize the gravity different principle of salt slurry and alkali slurry that the salt slurry is separated with the alkali slurry, obtaining solid-to-liquid ratio respectively is 0.6: 1 salt slurry and 0.3: 1 alkali slurry;
(c) treatment step of salt slurry: contain following material after the centrifuge separation in the mother liquor that salt slurry that will classification goes out in (b) step obtains: content is that sodium carbonate, the content that the caustic soda of 40g/l, solid sodium chloride that content is 150g/l and content are 80g/l is the hydrazine hydrate of 3g/l, the centrifugal solid sodium chloride that obtains is configured to solution, adds hydrochloric acid neutralization caustic soda wherein again through adding water, adjusting pH value is 8～9, being mixed with sodium chloride content is the refined brine of 250g/l, total ammonium content≤80ppm, send the chlor-alkali system as the raw material of producing chlorine and caustic soda this refined brine.
(d) treatment step of alkali slurry: alkali slurry that will classification goes out in (b) step obtains carbonate content after the centrifuge separation be 45% monohydrated sodium carbonate and mother liquor, this monohydrated sodium carbonate sent in the rotary kiln under 150 ℃ of conditions calcine, calcination time was controlled at 5 hours, remove the moisture in the monohydrated sodium carbonate, obtain sodium carbonate through pulverizing behind caustic soda and other impurity, to calcine the tail gas that produces simultaneously absorbs with water circulated in countercurrent in the air exhauster suction absorption tower, tail gas absorbs the back emptying, the absorption liquid that produces in the absorption tower send the sewage disposal collecting pit to handle through clear liquid behind the clarification filtration, and the water retrieval system of handling after qualified recycles;
(e) mother liquor reuse slurrying step: two kinds of mother liquors that produce in the treatment step with the treatment step of salt slurry and alkali slurry separate the back remittance together by centrifuge, keeping delivering to the slurrying step under 60 ℃ of conditions, continuation as next time saline and alkaline mixture the slurrying medium and recycle, under stirring condition, in mother liquor, add saline and alkaline, when the solid-to-liquid ratio of slurries at 0.3: 1, temperature configures slurries when being 80 ℃, no longer again, use hot water slurrying this moment, through behind the circulating pulp-making repeatedly, hydrazine hydrate in saline and alkaline and caustic soda constantly dissolve in the mother liquor, hydrazine hydrate content rises to 6g/l in mother liquor, when caustic soda content rises to 60g/l, with pump this mother liquor is returned vapo(u)rization system and distillation system and adopt that the conventional method evaporation is smart stays recovery hydrazine hydrate wherein, and the caustic soda that constantly consumes in the additional vapo(u)rization system.The mother liquor amount that reduces is replenished by the hot water that adds again, and mode of operation is the same.
Claims (1)
1. a recovering treatment of hydrated hydrazine by-product saline-alkali by urea method comprises the steps:
(a) slurrying step: by-product saline-alkali in the urea method hydrazine hydrate reaction under stirring condition, is added temperature in 65-90 ℃ hot water, make solid-to-liquid ratio and be 0.3～0.8: 1 the slurries that contain sodium carbonate, sodium chloride, caustic soda, hydrazine hydrate;
(b) separating step of salt slurry and alkali slurry: (a) salt slurry that mainly contains sodium chloride and the alkali slurry that mainly contains sodium carbonate are arranged in the slurries that make in the step, utilize the gravity different mining of salt slurry and alkali slurry with classifying equipoment the salt slurry to be separated with the alkali slurry, obtaining solid-to-liquid ratio respectively is 0.6-1: 1 salt slurry and 0.3-0.6: 1 alkali slurry;
(c) treatment step of salt slurry: will be in (b) step isolated salt slurry after the centrifuge separation, obtain caustic soda content be 2～8% and sodium chloride content be 65～85% solid sodium chloride and mother liquor, the solid sodium chloride that obtains is configured to solution, adds between acid adjustment its pH value to 8～9 through adding water, being mixed with sodium chloride content is the refined brine of 200～300g/l, total ammonium content≤80ppm, send the chlor-alkali system as the raw material of producing chlorine and caustic soda this refined brine;
(d) treatment step of alkali slurry: will be in (b) step isolated alkali slurry to obtain carbonate content after the centrifuge separation be 45～65% monohydrated sodium carbonate and mother liquor, this monohydrated sodium carbonate sent in the rotary kiln under 150～500 ℃ of conditions calcine, calcination time was controlled at 1～5 hour, remove the moisture in the monohydrated sodium carbonate, obtain sodium carbonate through pulverizing behind caustic soda and other impurity, to calcine the tail gas that produces simultaneously absorbs with water circulation in the air exhauster suction absorption tower, tail gas absorbs the back emptying, and the absorption liquid that produces in the absorption tower send the sewage disposal collecting pit through behind the clarification filtration;
(e) mother liquor reuse slurrying step: two kinds of mother liquors that produce in the treatment step with the treatment step of (c) salt slurry and (d) alkali slurry separate remittance afterwards together by centrifuge, keeping delivering to the slurrying step under 60～90 ℃ of conditions, continuation as next time saline and alkaline mixture the slurrying medium and recycle, under stirring condition, in mother liquor, add by-product saline-alkali, when the solid-to-liquid ratio of slurries 0.3～0.8: 1, temperature configures slurries when being 80～95 ℃, through behind the circulating pulp-making repeatedly, hydrazine hydrate in saline and alkaline and caustic soda constantly dissolve in the mother liquor, hydrazine hydrate rises to 5～15g/l in mother liquor, when caustic soda rises to 60～120g/l, with pump this mother liquor is returned vapo(u)rization system recovery hydrazine hydrate wherein, and the caustic soda that constantly consumes in the additional vapo(u)rization system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100218591A CN100389892C (en) | 2005-10-13 | 2005-10-13 | Recovering treatment of hydrated hydrazine by-product saline-alkali by urea method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100218591A CN100389892C (en) | 2005-10-13 | 2005-10-13 | Recovering treatment of hydrated hydrazine by-product saline-alkali by urea method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1745913A CN1745913A (en) | 2006-03-15 |
| CN100389892C true CN100389892C (en) | 2008-05-28 |
Family
ID=36165727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005100218591A Active CN100389892C (en) | 2005-10-13 | 2005-10-13 | Recovering treatment of hydrated hydrazine by-product saline-alkali by urea method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100389892C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101219973B (en) * | 2008-01-22 | 2010-06-02 | 浙江海虹控股集团有限公司 | Process for producing biurea |
| CN101786643B (en) * | 2010-03-18 | 2011-08-31 | 福建省邵武市榕丰化工有限公司 | Method for comprehensively utilizing byproduct salt and alkali waste in production of hydrazine hydrate by urea process |
| CN103896808A (en) * | 2014-04-12 | 2014-07-02 | 唐山晨虹实业有限公司 | Method of preparing azodiisobutyronitrile |
| CN109534361B (en) * | 2018-12-19 | 2021-03-09 | 青海盐湖工业股份有限公司 | Method for purifying sodium chloride from byproduct mixed salt |
| CN111498910B (en) * | 2020-05-26 | 2022-09-16 | 宜宾海丰和锐有限公司 | Resource utilization method of chlorination waste residue |
| CN112250049B (en) * | 2020-09-24 | 2023-06-20 | 江苏索普化工股份有限公司 | Separation method of hydrazine hydrate byproduct saline-alkali by urea method |
| CN115350500B (en) * | 2022-08-23 | 2023-10-13 | 宁夏日盛高新产业股份有限公司 | Byproduct comprehensive utilization system in foaming agent production |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1046328A (en) * | 1989-04-13 | 1990-10-24 | 成都华西化工研究所 | Alkali cycling process with production of hydrated hydrazine from urea |
| US5393508A (en) * | 1989-12-04 | 1995-02-28 | Atochem | Vaporization of solutions of hydrazine hydrate |
| CN1274685A (en) * | 2000-05-25 | 2000-11-29 | 赖中胜 | Method for denirifying from hydrazine hydrate salt mud |
| CN1351908A (en) * | 2001-12-18 | 2002-06-05 | 张庆陆 | Method for recovering hydrazine hydrate continuous distillation salt mud |
-
2005
- 2005-10-13 CN CNB2005100218591A patent/CN100389892C/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1046328A (en) * | 1989-04-13 | 1990-10-24 | 成都华西化工研究所 | Alkali cycling process with production of hydrated hydrazine from urea |
| US5393508A (en) * | 1989-12-04 | 1995-02-28 | Atochem | Vaporization of solutions of hydrazine hydrate |
| EP0952109A2 (en) * | 1989-12-04 | 1999-10-27 | Elf Atochem S.A. | Process for the evaporation of a hydrazine hydrate solution |
| CN1274685A (en) * | 2000-05-25 | 2000-11-29 | 赖中胜 | Method for denirifying from hydrazine hydrate salt mud |
| CN1351908A (en) * | 2001-12-18 | 2002-06-05 | 张庆陆 | Method for recovering hydrazine hydrate continuous distillation salt mud |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1745913A (en) | 2006-03-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100389892C (en) | Recovering treatment of hydrated hydrazine by-product saline-alkali by urea method | |
| CN111039310B (en) | Method for preparing sodium bicarbonate and co-producing ammonium sulfate from sodium sulfate | |
| US20170175228A1 (en) | Recovery of lithium from silicate minerals | |
| CA2644092A1 (en) | Extraction of lithium from lithium bearing minerals by caustic leaching | |
| CN202016881U (en) | System for producing soda ash and ammonium sulfate | |
| CN102198953A (en) | Methods for coproducing sodium carbonate and ammonium sulfate from melamine tail gas and mirabilite | |
| CN103555942A (en) | Method of decomposing tungsten concentrate | |
| CN108975375A (en) | A kind of high whiteness native sulfate of barium production technology of high pure and ultra-fine | |
| CN112551561A (en) | Method for producing active magnesium oxide from waste residues of spices | |
| CN103663505B (en) | Method for treating potassium feldspar according to sub-molten salt method to prepare potassium carbonate | |
| CN115947486A (en) | Desulfurization waste liquid recycling treatment process and system | |
| CN106011498A (en) | Method for preparing metal aluminum from bauxite through microwave chlorination | |
| CN101684523B (en) | Method for reclaiming molybdenum from waste alumina base catalyst containing molybdenum | |
| CN102628105B (en) | Method for comprehensively recycling and using baric waste slag in refined aluminum production process | |
| CN102040197B (en) | Method for removing ammonia nitrogen in hydrazine hydrate evaporation byproduct residues containing alkali salt by utilizing urea method | |
| CN111115674A (en) | Ground underground salt, alkali and calcium circulation green production method | |
| CN102515112A (en) | Method for preparing sodium sulfide from hydrogen sulfide waste gas produced in production of viscose fibre | |
| CN106636615B (en) | The mica treatment process of lithium carbonate is prepared using lepidolite | |
| CN100368298C (en) | Method for preparing strontium carbonate in high purity from celestite ore in mid and low grades | |
| CN208732632U (en) | The production equipment of sodium bicarbonate | |
| US3619350A (en) | Chlorine dioxide pulp bleaching system | |
| CN112279284B (en) | Method for comprehensively utilizing high-sulfur bauxite and Bayer process red mud | |
| CN115417431A (en) | Method for extracting potassium in process of producing aluminum oxide by Bayer process | |
| EP0180604A1 (en) | Removal of organics from bayer process streams. | |
| CN1522961A (en) | Process for preparing calcined soda by trona containing abundant sodium bicarbonate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee |
Owner name: YIBIN TIANYUAN GROUP CO., LTD. Free format text: FORMER NAME OR ADDRESS: YIBIN TIANYUAN CO., LTD. |
|
| CP03 | Change of name, title or address |
Address after: Jiangbei District, Yibin City, Sichuan Province Patentee after: YiBin TianYuan Group Co., Ltd. Address before: Jiangbei District, Yibin City, Sichuan Province Patentee before: Tianyuan Co., Ltd., Yibin City |