CN102040197B - Method for removing ammonia nitrogen in hydrazine hydrate evaporation byproduct residues containing alkali salt by utilizing urea method - Google Patents
Method for removing ammonia nitrogen in hydrazine hydrate evaporation byproduct residues containing alkali salt by utilizing urea method Download PDFInfo
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- CN102040197B CN102040197B CN2010105478346A CN201010547834A CN102040197B CN 102040197 B CN102040197 B CN 102040197B CN 2010105478346 A CN2010105478346 A CN 2010105478346A CN 201010547834 A CN201010547834 A CN 201010547834A CN 102040197 B CN102040197 B CN 102040197B
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Abstract
The invention relates to a method for processing hydrazine hydrate evaporation byproduct residues containing alkali salt by utilizing a urea method, in particular to a method for removing ammonia nitrogen in hydrazine hydrate evaporation byproduct residues containing alkali salt by utilizing a urea method. The method provided by the invention comprises the following steps: dissolving the hydrazine hydrate evaporation byproduct residues containing the alkali salt into water to prepare crude brine; detecting and determining the mass concentration of sodium hydroxide, sodium carbonate and ammonia nitrogen in the crude brine; blasting chlorine into the crude brine to prepare sodium hypochlorite; and removing the excessive sodium hypochlorite after the content of the ammonia nitrogen is reduced to below 15PPm, thus obtaining the brine with the content of the ammonia nitrogen lower than 15PPm. The invention can treat the hydrazine hydrate evaporation byproduct residues containing the alkali salt so as to meet the requirements for the mass concentration of the ammonia nitrogen in the brine for electrolyzing caustic soda, realizes the comprehensive recycle of the hydrazine hydrate evaporation byproduct residues containing the alkali salt, fully utilizes resources, is environment-friendly, and has the advantages of less investment, simple process, easy operation, no new three-waste generation, low cost and economic feasibility.
Description
Technical field
The present invention relates to the treatment process that a kind of Wyler's process Hydrazine Hydrate 80 by-product contains the alkali salt slag, particularly a kind of Wyler's process Hydrazine Hydrate 80 by-product contains the removal methods of the ammonia nitrogen in the alkali salt slag.
Background technology
Hydrazine Hydrate 80 is widely used in medicine, the pesticide producing as a kind of important chemical material, and China mainly produces Hydrazine Hydrate 80 with urea hypochlorite oxidation method at present, will produce a large amount of sodium-chlor and yellow soda ash inevitably in the process of production.Yellow soda ash mainly separates from hydrazine hydrate solution through the way of freezing and crystallizing; Sodium-chlor and remaining a small amount of yellow soda ash then separate through consecutive evaporation, produce to contain the alkali salt slag in a large number, and its composition is a sodium-chlor 70%; Yellow soda ash 10～15%; Sodium hydroxide 2%, water 12～15%, 0.5～0.6% hydrazine and amine.These materials that contain in the alkali salt slag all have utility value, and wherein sodium-chlor, yellow soda ash are the raw and auxiliary materials of electrolysis production sodium hydroxide, but because hydrazine and ammonia etc. contain the material existence of ammonia nitrogen; Contain the alkali salt slag and in electrolytic process, can produce nitrogen trichloride; Nitrogen trichloride is a kind of explosive substance, and affects safety production should strictly be controlled in suitability for industrialized production; The undressed alkali salt slag that contains can not be directly as the sodium chloride electrolysis raw material, and this has just limited the use that contains the alkali salt slag.Therefore, the ammonia nitrogen of removing wherein like economically viable mode how is to contain the key link that the alkali salt slag is effectively recycled.In the prior art, commonly used to remove ammonia nitrogen technology be the calcination method, promptly is to carry out calcination and make material decomposition, the volatilization that contains ammonia nitrogen containing the alkali salt slag, and the resulting alkali salt slag that contains promptly can be used as former, the auxiliary material of electrolysis, but its technological operation is complicated, and facility investment is big.On the other hand, use this method must be earlier with containing the preheating of alkali salt slag, energy consumption be big, and in warm, containing Hydrazine Hydrate 80 contained in the alkali salt slag can be discharged in the atmosphere contaminate environment with gas form.
Chinese patent 200510021859.1 discloses a kind ofly produces the recovery and treatment method of Hydrazine Hydrate 80 to the by product in the evaporative process with urea, Youxiaolin, sodium hydroxide oxidation style; It comprises the separating step of slurrying step, salt slurry and alkali slurry, the treatment step of salt slurry, the treatment step and the mother liquor reuse slurrying step of alkali slurry; This invention is adopted saline and alkaline with after the fractional separation after the hot water slurrying; To reclaim solid salt and directly change into salt solution, and obtain refined brine after the processing and return electrolyzer.But this treatment process is just simply transferred to the part ammonia nitrogen in the salt slag in the mother liquor with hot water, repeatedly turns back in the Hydrazine Hydrate 80 vapo(u)rization system after the circulation again, and total ammonium can't reach the requirement of electrolysis with the total ammonium≤15ppm of salt still up to 80ppm in the salt solution after the processing.
Application number is that 00112969.4 Chinese patent has proposed a kind of method of removing ammonia nitrogen; This method is through repeatedly embathing the displacement hydrazine hydrate salt mud with the caustic soda soln that contains saturated sodium-chloride; Nitrogenous substances in the salt slurry is separated with solid matter; There is following shortcoming in this method: the one, and complex process, efficient is low; The 2nd, mother liquor solubility is low, increases steam consumption after returning vapo(u)rization system, and the Hydrazine Hydrate 80 cost raises; The 3rd, the caustic soda soln that contains saturated sodium-chloride that adds is brought sodium-chlor again into, increases the salt amount of adopting of vapo(u)rization system, influences Hydrazine Hydrate 80 output.
Application number is a kind of method with nitrogenous type of material of the hydrazine class reductibility in the saline and alkaline mud of hypochlorite heated oxide of Chinese patent proposition of 01108544.4; There is following shortcoming in this method: the one, and the Youxiaolin that adds needs preparation in addition; Both consumed caustic soda, and consumed chlorine again, processing cost is high; The 2nd, it is unprocessed to produce a kind of toxic gas of chloramines that cries in the reaction process, influences environment, health risk.
In sum; The whole bag of tricks of the prior art or ammonia nitrogen can not reach the standard-required of production of caustic soda, or fail to make full use of resource, and cost is high when reaching standard-required; No economic feasibility; Or having the new three wastes to produce, technology awaits further simplification, further improves in the no new three wastes generation of realization with aspect reducing cost.
Summary of the invention
The object of the present invention is to provide a kind of Wyler's process Hydrazine Hydrate 80 evaporation by-product to contain the ammonia nitrogen removal method in the alkali salt slag, it can make Hydrazine Hydrate 80 evaporation by-product after the processing contain the alkali salt slag to reach caustic soda electrolysis and use the salt solution requirement, realize that Hydrazine Hydrate 80 evaporation by-product contains the recycling of alkali salt slag; Make full use of resource, the protection environment, plant investment is little; Technology is simple, and is easy to operate, and the no new three wastes produce; Cost is low, has economic feasibility.
Technical scheme of the present invention is:
A kind of Wyler's process Hydrazine Hydrate 80 evaporation by-product contains the ammonia nitrogen removal method in the alkali salt slag, and its production stage is following: earlier Hydrazine Hydrate 80 is evaporated by-product and contain the alkali salt slag and be dissolved in water and process crude brine; Detect the mass concentration of confirming sodium hydroxide, yellow soda ash and ammonia nitrogen in the step 1 gained crude brine solution; Prepare Youxiaolin to the logical chlorine of crude brine, after the ammonia nitrogen mass concentration in the crude brine solution drops to below the 15PPm, remove excessive Youxiaolin; Obtain the salt solution of ammonia-nitrogen content less than 15PPm.
As to further improvement of the present invention, the mass concentration of sodium-chlor is 250～280g/l in the described crude brine.
As to further improvement of the present invention, the temperature of reaction of described logical chlorine reaction is controlled at 20～80 ℃, and the reaction times is 14～16 hours.
As to further improvement of the present invention, described method of removing excessive Youxiaolin is to add an amount of sulphite according to the Youxiaolin mass concentration in the crude brine solution.
As to further improvement of the present invention, described ammonia nitrogen mass concentration is carried out sedimentation less than the salt solution of 15PPm and is handled, and removes insoluble impurities in the salt solution, obtains being fit to the salt solution that caustic soda electrolysis is used.
As to further improvement of the present invention, the described settling time is 4～5 hours.
As to further improvement of the present invention, the logical chlorine reaction institute of described crude brine expellant gas absorbs through device for absorbing tail gas, and absorption liquid is a service water.
Principal reaction mechanism of the present invention is: chlorine and sodium hydroxide, yellow soda ash reaction generate Youxiaolin, and Youxiaolin and ammonia nitrogen reaction generate nitrogen, chloramines, react as follows:
2NaOH+Cl
2→NaClO+NaCl+H
2O
2Na
2CO
3+Cl
2+H
2O→2NaHCO
3+NaClO+NaCl
NH
3+NaClO→NH
2CL↑+NaOH
N
2H
4·H
2O+2NaClO→N
2↑+3H
2O+2NaCl
Beneficial effect of the present invention is:
The present invention compared with prior art has the following advantages: the present invention utilizes chlorine to generate Youxiaolin with sodium hydroxide, the yellow soda ash reaction in the salt slag; Youxiaolin generates nitrogen, chloramines with the ammonia nitrogen reaction again; Gas such as nitrogen, chloramines volatilizees from salt solution, realizes removing of ammonia nitrogen.Compare with Chinese patent 200510021859.1, the present invention adopts the chemical process removal of ammonia and nitrogen, has characteristics such as technology is simple, ammonia nitrogen removal is effective, handles the mass concentration≤15ppm of total ammonium in the salt solution of back, can reach the requirement that caustic soda electrolysis is used.Compare with Chinese patent 00112969.4, the salt solution after the present invention handles can directly supply caustic soda to use, and does not have any material and returns the Hydrazine Hydrate 80 production system; Mother liquor returns production system after no a large amount of processing; Avoid bringing into a large amount of moisture content and sodium-chlor, the steam consumption when not increasing evaporation, the salt amount of adopting in the evaporation step does not increase yet; Do not influence the ordinary production of hydrazine hydrate production, its output and energy consumption are not had influence.Compare with Chinese patent 01108544.4; The present invention makes full use of the sodium hydroxide, yellow soda ash and the chlorine reaction that contain in the alkali salt slag and generates Youxiaolin; Do not need to consume caustic soda in addition, cost is lower, has increased device for absorbing tail gas simultaneously; Absorb the toxic gas that produces in the treating processes, avoided secondary pollution.
In a word, the present invention can make Hydrazine Hydrate 80 evaporation by-product contain the brinish requirement that the alkali salt slag reaches the caustic soda electrolysis use after treatment, realizes comprehensively recyling Hydrazine Hydrate 80 evaporation by-product and contains the alkali salt slag; Make full use of resource, the protection environment is invested little; Technology is simple, and is easy to operate, and the no new three wastes produce; Cost is low, has economic feasibility.
Embodiment
Below in conjunction with embodiment the present invention is done further explain, but the present invention has more than and is limited to these embodiment.
Embodiment 1:
Prepare Hydrazine Hydrate 80 by ordinary method of the prior art, at first 30% caustic soda put into the diluted alkaline Preparation tank, add certain amount of industrial water again, with pump constantly circulation mix, the diluted alkaline that is mixed with the sodium hydroxide mass concentration and is after 22～24% is for use; Again service water is put into urea liquid Preparation tank, under agitation add solid urea and catalyzer, it is solution for later use behind 310～340g/l that solid urea is dissolved into mass concentration; Then diluted alkaline is sent in the sodium hypochlorite reaction device by certain flow, fed chlorine, with-5～5 ℃ of chilled brines coolings, control reaction temperature is below 30 ℃, makes that to contain available chlorine be 8～12% chlorine bleach liquor.With pump chlorine bleach liquor and urea liquid are mixed the back contains Hydrazine Hydrate 80 with steam heating to 100～110 ℃ reaction generation thick solution by a certain percentage; The thick solution of Hydrazine Hydrate 80 is cooled to＜sends in the crystallization kettle after 50 ℃ with recirculated water then; With＜cooling of-5 ℃ chilled brine; After temperature was reduced to 0 ℃, spinning went out in the thick hydrazine hydrate solution 70% yellow soda ash.Send in the pump feed evaporator and evaporate removing the thick solution of Hydrazine Hydrate 80 behind the yellow soda ash, after water and the Hydrazine Hydrate 80 evaporation, the Chemical Composition mass percent that contains the alkali salt slag that obtains is following:
Sodium-chlor: 65～70% yellow soda ash: 10～15% caustic soda: 3～4%
N
2H
4H
2O:0.5～0.6% surplus is 12～20% to be water and other trace impurity.
Embodiment 2:
A kind of Wyler's process Hydrazine Hydrate 80 evaporation by-product contains the ammonia nitrogen removal method in the alkali salt slag, and the Hydrazine Hydrate 80 evaporation by-product of getting embodiment 1 method gained contains the alkali salt slag, and its Chemical Composition is following:
Sodium-chlor: 65% yellow soda ash: 15% caustic soda: 3%
N
2H
4H
2All the other 16.5% are water and other trace impurity for O:0.5%.
Above-mentioned salt slag is handled by following production stage:
Step 1: 1000kg Hydrazine Hydrate 80 by-product is contained the alkali salt slag be made into 250g/l salt solution with the service water water dissolution;
Step 2: detect in step 1 solution sodium hydroxide, the total mass concentration of yellow soda ash and be 4% and the ammonia nitrogen mass concentration be 2000PPm;
Step 3: to the logical equably chlorine of saturated crude brine of step 1, control reaction temperature is 20 ℃;
Step 4: gases such as the chloramines of discharge absorb through device for absorbing tail gas;
Step 5: logical chlorine after 16 hours the ammonia nitrogen mass concentration reduce to 14.5PPm, detecting the Youxiaolin mass concentration is 3.0g/l, adds 15Kg sodium sulfate and removes excessive Youxiaolin;
Step 6:, remove insoluble impurities in the salt solution and obtain being fit to the salt solution that caustic soda electrolysis is used with salt solution sedimentation 4 hours.
Embodiment 3:
A kind of Wyler's process Hydrazine Hydrate 80 evaporation by-product contains the ammonia nitrogen removal method in the alkali salt slag, and the Hydrazine Hydrate 80 evaporation by-product of getting embodiment 1 method gained contains the alkali salt slag, and its Chemical Composition is following:
Sodium-chlor: 68% yellow soda ash: 13% caustic soda: 4%
N
2H
4H
2All the other 14.6% are water and other trace impurity for O:0.4%.
Above-mentioned salt slag is handled by following production stage:
Step 1: 1000kg Hydrazine Hydrate 80 by-product is contained the alkali salt slag be made into 270g/l salt solution with the service water water dissolution;
Step 2: detect in step 1 solution sodium hydroxide, the total mass concentration of yellow soda ash and be 4.5% and the ammonia nitrogen mass concentration be 1900PPm;
Step 3: to the logical equably chlorine of saturated crude brine of step 1, control reaction temperature is 50 ℃;
Step 4: gases such as the chloramines of discharge absorb through device for absorbing tail gas;
Step 5: logical chlorine after 15 hours ammonia-nitrogen content reduce to 13PPm, detecting the Youxiaolin mass concentration is 4.0g/l, adds the 20Kg S-WAT and removes excessive Youxiaolin;
Step 6:, remove insoluble impurities in the salt solution and obtain being fit to the salt solution that caustic soda electrolysis is used with salt solution sedimentation 5 hours.
Embodiment 4:
A kind of Wyler's process Hydrazine Hydrate 80 evaporation by-product contains the ammonia nitrogen removal method in the alkali salt slag,, the Hydrazine Hydrate 80 evaporation by-product of getting embodiment 1 method gained contains the alkali salt slag, and its Chemical Composition is following:
Sodium-chlor: 70% yellow soda ash: 10% caustic soda: 4%
N
2H
4H
2All the other 15.5% are water and other trace impurity for O:0.5%.
Above-mentioned salt slag is handled by following production stage:
Step 1: 1000kg Hydrazine Hydrate 80 by-product is contained the alkali salt slag be made into 280g/l salt solution with the service water water dissolution;
Step 2: detect in step 1 solution sodium hydroxide, the total mass concentration of yellow soda ash and be 3.5% and the ammonia nitrogen mass concentration be 2200PPm;
Step 3: to the logical equably chlorine of saturated crude brine of step 1, control reaction temperature is 80 ℃;
Step 4: gases such as the chloramines of discharge absorb through device for absorbing tail gas;
Step 5: logical chlorine after 14 hours the ammonia nitrogen mass concentration reduce to 10PPm, detecting the Youxiaolin mass concentration is 2.0g/l, adds the 10Kg S-WAT and removes excessive Youxiaolin;
Step 6:, remove insoluble impurities in the salt solution and obtain being fit to the salt solution that caustic soda electrolysis is used with salt solution sedimentation 5 hours.
Embodiment 5:
A kind of Wyler's process Hydrazine Hydrate 80 evaporation by-product contains the ammonia nitrogen removal method in the alkali salt slag, and the Hydrazine Hydrate 80 evaporation by-product of getting embodiment 1 method gained contains the alkali salt slag, and its Chemical Composition is following:
Sodium-chlor: 68% yellow soda ash: 13% caustic soda: 4%
N
2H
4H
2All the other 14.6% are water and other trace impurity for O:0.4%.
Above-mentioned salt slag is handled by following production stage:
Step 1: 1000kg Hydrazine Hydrate 80 by-product is contained the alkali salt slag be made into 270g/l salt solution with the service water water dissolution;
Step 2: detect in step 1 solution sodium hydroxide, the total mass concentration of yellow soda ash and be 4.5% and ammonia nitrogen mass concentration 1900PPm;
Step 3: to the logical equably chlorine of saturated crude brine of step 1, control reaction temperature is 50 ℃;
Step 4: gases such as the chloramines of discharge absorb through device for absorbing tail gas;
Step 5: logical chlorine after 15 hours ammonia-nitrogen content reduce to 13PPm, detecting the Youxiaolin mass concentration is 4.0g/l, adds the 25Kg potassium sulfite and removes excessive Youxiaolin;
Step 6:, remove insoluble impurities in the salt solution and obtain being fit to the salt solution that caustic soda electrolysis is used with salt solution sedimentation 5 hours.
Claims (4)
1. a Wyler's process Hydrazine Hydrate 80 evaporation by-product contains the ammonia nitrogen removal method in the alkali salt slag, it is characterized in that:
Its production stage is following: earlier Hydrazine Hydrate 80 is evaporated by-product and contain the alkali salt slag and be dissolved in water and process crude brine; Detect the mass concentration of confirming sodium hydroxide, yellow soda ash and ammonia nitrogen in the gained crude brine solution; Generate Youxiaolin to the logical chlorine reaction of crude brine, after the ammonia-nitrogen content in the crude brine solution drops to mass concentration and is lower than below the 15PPm, remove excessive Youxiaolin, obtain the salt solution of ammonia nitrogen mass concentration less than 15PPm;
The mass concentration of sodium-chlor is 250～280g/l in the described crude brine;
The temperature of reaction of described logical chlorine reaction is controlled at 20～80 ℃, and the reaction times is 14～16 hours;
Described method of removing excessive Youxiaolin is to add an amount of sulphite according to the Youxiaolin mass concentration in the crude brine solution.
2. Wyler's process Hydrazine Hydrate 80 evaporation by-product according to claim 1 contains the ammonia nitrogen removal method in the alkali salt slag; It is characterized in that: described ammonia nitrogen mass concentration is carried out the sedimentation processing less than the salt solution of 15PPm; Remove insoluble impurities in the salt solution, obtain being fit to the salt solution that caustic soda electrolysis is used.
3. Wyler's process Hydrazine Hydrate 80 evaporation by-product according to claim 2 contains the ammonia nitrogen removal method in the alkali salt slag, and it is characterized in that: the described settling time is 4～5 hours.
4. Wyler's process Hydrazine Hydrate 80 evaporation by-product according to claim 1 contains the ammonia nitrogen removal method in the alkali salt slag, it is characterized in that: the logical chlorine reaction institute of described crude brine expellant gas absorbs through device for absorbing tail gas, and absorption liquid is a service water.
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|---|---|---|---|
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| JP6331145B2 (en) * | 2014-11-26 | 2018-05-30 | 三菱重工環境・化学エンジニアリング株式会社 | Ammonia treatment system |
| CN104817098A (en) * | 2015-04-15 | 2015-08-05 | 杭州海虹精细化工有限公司 | Industrial by-product high ammonia-nitrogen sodium chloride treatment method |
| 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 |
| CN111233126B (en) * | 2020-03-30 | 2022-05-20 | 西北民族大学 | Treatment method of tricyclazole production wastewater |
| CN111485247A (en) * | 2020-05-31 | 2020-08-04 | 湖南申联环保科技有限公司 | Resourceful treatment device and method for high-chlorine organic hazardous waste incineration fly ash |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1322684A (en) * | 2001-06-15 | 2001-11-21 | 赖中胜 | Method of eliminating nitrogenous matters from hydrazine hydrate saline-alkali mud |
| CN1686856A (en) * | 2005-04-22 | 2005-10-26 | 宜宾天原股份有限公司 | Method of treating wastewater containing salt for producing hydrazine hydrate by carbamide method |
| CN101058468A (en) * | 2006-04-18 | 2007-10-24 | 潍坊亚星集团有限公司 | Method of processing hydrazine hydrate waste water by ketone linking nitrogen method |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1322684A (en) * | 2001-06-15 | 2001-11-21 | 赖中胜 | Method of eliminating nitrogenous matters from hydrazine hydrate saline-alkali mud |
| CN1686856A (en) * | 2005-04-22 | 2005-10-26 | 宜宾天原股份有限公司 | Method of treating wastewater containing salt for producing hydrazine hydrate by carbamide method |
| CN101058468A (en) * | 2006-04-18 | 2007-10-24 | 潍坊亚星集团有限公司 | Method of processing hydrazine hydrate waste water by ketone linking nitrogen method |
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