CN109503432A - A kind of ADC foaming agent producing process - Google Patents
A kind of ADC foaming agent producing process Download PDFInfo
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- CN109503432A CN109503432A CN201811622131.8A CN201811622131A CN109503432A CN 109503432 A CN109503432 A CN 109503432A CN 201811622131 A CN201811622131 A CN 201811622131A CN 109503432 A CN109503432 A CN 109503432A
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- China
- Prior art keywords
- adc
- reaction
- biruea
- foaming agent
- urea
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C281/00—Derivatives of carbonic acid containing functional groups covered by groups C07C269/00 - C07C279/00 in which at least one nitrogen atom of these functional groups is further bound to another nitrogen atom not being part of a nitro or nitroso group
- C07C281/20—Derivatives of carbonic acid containing functional groups covered by groups C07C269/00 - C07C279/00 in which at least one nitrogen atom of these functional groups is further bound to another nitrogen atom not being part of a nitro or nitroso group the two nitrogen atoms of the functional groups being doubly-bound to each other, e.g. azoformamide
Abstract
It foams agent producing process, including condensation process, oxidation operation, ADC foaming agent refining step the present invention provides a kind of ADC.It joined the hydrochloric acid of oxidation operation recycling in condensation process, concentration of hydrochloric acid, which reaches 20-30%, can meet condensation requirement, and the cost recovery of hydrochloric acid is lower, and also reduces the production cost of ADC foaming agent；In oxidation operation, surfactant joined, so that particle be made to be easier to be precipitated, partial size is thinner；When oxidation operation closes to an end, urea is added into reaction solution, the oxidation reaction for promoting biruea is mobile to positive reaction direction；It is condensed using the hydrazine hydrate and hydrochloric acid of concentrate, guarantees that the content of effecting reaction object is higher, improve production efficiency；It is provided with flow-stopping plate in stills for air blowing internal side wall, using propeller agitator, keeps the temperature of reactant in stills for air blowing more uniform；ADC foaming agent product is crushed using fluidized bed airflow pulverizer, is classified, the ADC foaming agent product of different-grain diameter can be obtained.
Description
Technical field
The invention belongs to ADC foaming agent technical field more particularly to a kind of ADC foaming agent producing process.
Background technique
With the diversification of ADC foaming agent product applications, high-endization of product category, downstream manufacturers foam to ADC
The individual demands such as properties of product, the technological service of agent are continuously improved, and with greater need for ADC foaming agent, manufacturing enterprise has Continuous Innovation
Ability, and the product of differentiation and applicability can be developed according to customer demand.Domestic traditional production technology and equipments are
It is difficult to meet the requirement to foaming agent product granularity, the product of production has average grain diameter greatly (generally at 12-15 μm) mostly, grain
Degree distribution is wide (1-45 μm), and product particle size is uneven, and the temperature range for causing product to there is decomposition generation gas is wide,
The speed of release gas is uneven, controllable system is low.And the wastewater treatment generated in production process is more difficult, the salt of by-product
Acid etc. cannot efficiently use, and the production cost for causing product is higher.
Chinese patent (102850243 B of CN, December 11 2013 day for announcing) discloses the ADC of uniform particle sizes a kind of
Average grain diameter 3-6 microns of ultra-fine ADC foaming agent powder is made in the preparation method of foaming agent, this method first；Biruea is added
In water, it is made into suspension containing biruea, inorganic acid is added and adjusts acidity, adds catalyst potassium bromide or sodium bromide, stirring is simultaneously
Heating, finally adds ultra-fine ADC foaming agent powder and makees crystal seed；Last oxidizer carries out oxidation reaction and prepares uniform particle sizes
ADC foaming agent.The patent makees crystal seed, therefore, the product using the ultra-fine ADC foaming agent powder that average grain diameter is 3-6 microns
Minimum grain size still cannot fully meet customer demand also at 10 microns or more.In addition, this patent adjusts biruea using sulfuric acid
The acidity of suspension has been reintroduced back to sulfate ion into solution, and oxidation operation selects chlorine or liquor natrii hypochloritis, from
And introduce chloride ion and sodium ion, the mother liquor composition after causing final filtration ADC foaming agent is complex, recycle compared with
For difficulty.
Chinese patent (105859592 B of CN, May 18 2108 day for announcing) discloses a kind of ADC foaming agent and produced
In journey by-product hydrochloric acid recycle method, using carbon steel filter filter out containing biruea and ADC after, be preheated to 60
~70 DEG C, it is then sent to the parsing of resolving hydrochloric acid tower, obtains hydrogen chloride gas.Although the technique recycles hydrochloric acid,
By processing steps such as preheating, resolving hydrochloric acid towers, the energy consumption of integrated operation process is higher, and the cost of by-product hydrochloric acid is also higher.
Summary of the invention
To solve problems of the prior art, present invention provide the technical scheme that
A kind of ADC foaming agent producing process, includes the following steps:
(1) it is condensed process, the hydrazine hydrate after urea and evaporation and concentrating is dissolved in contracting according to the ratio that mass ratio is 2.5:1
Kettle is closed, the hydrochloric acid of oxidation operation recycling is added, the pH value of urea hydrazine hydrate solution is adjusted to 4.5-6.0, condensation kettle is adjusted and adds
Solution is warming up to 100-120 DEG C with the speed of 1-3 DEG C/min by thermal, and constant temperature carries out condensation reaction 400-600min；
(2) after urea hydrazine hydrate solution completes condensation reaction in condensation kettle, reaction solution is being pressed for biruea refining step
It is filtered in filter, obtains biruea solid particle, biruea solid particle is washed in filter press using 75-85 DEG C of hot water
It washs, washing to the pH value of cleaning solution is 7 ± 0.2；
(3) the biruea solid particle for completing washing and water are added oxidation operation according to the ratio that solid-to-liquid ratio is 1:2-3
Into stills for air blowing, halide salt is added as catalyst, while surfactant is added, chlorine is passed through into solution and is reacted,
It is shifted in stills for air blowing coil pipe using the heat that chilled brine generates reaction, makes reaction temperature control at 40 DEG C or less；Work as reaction
When degree reaches 95% or more, it is added urea into reaction solution, the mass ratio of urea and reaction solution is 1:800-1000；
(4) ADC foaming agent refining step finally uses water by the reaction solution of oxidation operation output after filtration washing step by step
Rinse to pH value it is dry 6.5 or more, it is dry after ADC foaming agent enter after airslide disintegrating mill is crushed, is classified to get arriving
ADC product；
(5) biruea filtrated stock recovery process, by step (2) filtrated stock and washing water carry out it is cooling, precipitate,
Biruea is deposited in below filtrate receiver, enters step (3) after precipitating biruea is again passed by washing, supernatant liquor is steamed through triple effect
By-product ammonium chloride is obtained after hair device evaporation；The temperature that distilled water is generated during triple effect evaporation is 70-80 DEG C, is used for step
(2) biruea is washed in；
(6) ADC foaming agent filtrated stock recovery process, the reaction solution filtrated stock that oxidation operation in step (4) is exported
Step by step concentration is washed through band filter, the hydrochloric acid that concentration is 20%-30% is obtained, stores into head tank, in step (1)
Adjust urea hydrazine hydrate solution pH value.
Further, the concentration of hydrazine hydrate is 6%-20% after evaporation and concentrating in step (1).
Further, the halogenation salt catalyst in step (3) is one of sodium chloride, sodium bromide, ammonium bromide.
Further, the surfactant in step (3) is cyclic amine compound or derivatives thereof.
Further, the mass ratio of the additive amount and biruea solid particle aqueous solution of surfactant is in step (3)
0.01-0.1:100。
Further, the stills for air blowing in step (3) use 2-5 layers of propeller agitator, set in stills for air blowing internal side wall
It is equipped with flow-stopping plate.
Further, airslide disintegrating mill described in step (4) is fluidized bed airflow pulverizer, and the minimum grain size of crushing is
1-2μm。
Further, it is also equipped with cyclone separator in fluidized bed airflow pulverizer, be used for ADC product according to partial size
Classification.
Surfactant is added in the present invention in oxidation operation and the basic principle of urea is: when oxidation reaction carries out,
When the partial size of generation ADC blowing-agent particle is smaller, specific surface area is very big, and surface Gibbs free energy is very big at this time, Zhi Nengyi
Gibbs free energy is reduced by increasing the partial size of ADC blowing-agent particle；When a small amount of surfactant is added in the reaction system,
Gibbs free energy can be significantly reduced, surface tension of liquid is reduced, particle is made to attenuate and be easier to be precipitated.After oxidation reaction
Phase, with reaction union II urea concentration reduction, reaction rate reduce, and the intake of oxidant chlorine be it is excessive, it is excessive
Oxidant enters the quality that subsequent handling will affect product；Urea is added at this time, on the one hand can promote the oxidation of biruea to
Positive reaction direction is mobile, on the other hand can also consume extra oxidant.
It is returned compared with prior art, the invention has the following advantages that (1) present invention joined oxidation operation in condensation process
The hydrochloric acid of receipts, the hydrochloric acid of recycling only need concentrate to 20-30%, and the other impurities recycled in hydrochloric acid filter back through millipore filter
Receive, hence it is evident that reduce the cost recovery of hydrochloric acid, while also reducing the production cost of ADC foaming agent；(2) it is aoxidizing
In process, cyclic amine compound or derivatives thereof is added and is used as nonionic surface active agent, reduces newly-generated ADC foaming agent
The Gibbs free energy of particle surface, so that particle be made to be easier to be precipitated, partial size is thinner；(3) when oxidation operation closes to an end,
Urea is added into reaction solution, the oxidation reaction for not only having promoted biruea is mobile to positive reaction direction, but also consumes extra oxygen
Agent avoids it from impacting product quality, and the process does not introduce other impurities also；(4) it is mentioned in condensation process use
The hydrochloric acid of dense hydrazine hydrate and concentrate, the content of effecting reaction object is higher in the condensation kettle of guarantor unit's volume, and reduces
Evaporation capacity in subsequent ammonium chloride triple effect evaporation, improves production efficiency；(5) using filter press to the biruea produced into
Row filtering, while biruea is washed in filter press, compared with traditional sink, hence it is evident that reduce slurry
Amount, reduces the washing loss of reaction product；(6) flow-stopping plate is provided in stills for air blowing internal side wall, stills for air blowing use 2-5 layers of spiral shell
Propeller mixer improves stirring efficiency compared with traditional anchor agitator, makes the temperature of reactant in stills for air blowing more
Uniformly, it is more advantageous to and produces the lesser ADC foaming agent product of granularity；(7) it is foamed using fluidized bed airflow pulverizer to ADC
Agent product is crushed, and minimum grain size can reach 1-2 μm, is in addition additionally provided with cyclone separator on crusher, difference can be obtained
The ADC foaming agent product of partial size, to meet the needs of various clients.
Specific embodiment
In the following, in conjunction with embodiments of the present invention will be described.
The present invention provides the production technologies of ADC foaming agent, the specific steps are as follows:
(1) it is condensed process, the hydrazine hydrate that urea and concentration are 10% is dissolved in contracting according to the ratio that mass ratio is 2.5:1
Kettle is closed, the hydrochloric acid of oxidation operation recycling is added, the pH value of urea hydrazine hydrate solution is adjusted to 4.9, adjusts condensation kettle heating dress
It sets and solution is warming up to 105 DEG C with the speed of 1.8 DEG C/min, constant temperature carries out condensation reaction 150min.
(2) after urea hydrazine hydrate solution completes condensation reaction in condensation kettle, reaction solution is being pressed for biruea refining step
It is filtered in filter, obtains biruea solid particle, biruea solid particle is washed in filter press using 82 DEG C of hot water,
Washing to the pH value of cleaning solution is 7.0.
(3) the biruea solid particle for completing washing and water are added oxidation operation according to the ratio that solid-to-liquid ratio is 1:2.5
Into stills for air blowing, sodium bromide is added as catalyst, while cyclic amine compound or derivatives thereof is added and is used as surfactant,
The additive amount of surfactant and the mass ratio of biruea solid particle aqueous solution are 0.08:100；Be passed through into solution chlorine into
Row reaction is shifted using the heat that 5 DEG C of chilled brines generate reaction in stills for air blowing coil pipe, make reaction temperature control 40 DEG C with
Under；Stills for air blowing use 2-5 layers of propeller agitator, are provided with flow-stopping plate in stills for air blowing internal side wall；When the extent of reaction reaches
When 95% or more, it is added urea into reaction solution, the mass ratio of urea and reaction solution is 1:1000.
(4) ADC foaming agent refining step is finally rinsed with water after the reaction solution filtering of oxidation operation output to pH value
It is dry after 6.5 or more, it is dry after ADC foaming agent enter after fluidized bed airflow pulverizer crushed, is classified, crushing
Minimum grain size is 1-2 μm, fluidized bed airflow pulverizer pass through the cyclopneumatic separator wherein installed to product be classified to get
To the ADC product of various specifications.
(5) biruea filtrated stock recovery process, by step (2) filtrated stock and washing water carry out it is cooling, precipitate,
Biruea is deposited in below filtrate receiver, enters step (3) after precipitating biruea is again passed by washing, supernatant liquor is steamed through triple effect
By-product ammonium chloride is obtained after hair device evaporation.The temperature that distilled water is generated during triple effect evaporation is 70-80 DEG C, is used for step
(2) biruea is washed in.
(6) ADC foaming agent filtrated stock recovery process, the reaction solution filtrated stock that oxidation operation in step (4) is exported
Step by step concentration is washed through band filter, obtains the hydrochloric acid that concentration is 25%, storage can adjust urea into head tank in step (1)
Hydrazine hydrate solution pH value.
The present invention joined the hydrochloric acid of oxidation operation recycling in condensation process, and the hydrochloric acid of recycling only needs concentrate to 20-30%,
Recycling hydrochloric acid in other impurities be recovered by filtration through millipore filter, hence it is evident that the cost recovery for reducing hydrochloric acid, simultaneously
Also reduce the production cost of ADC foaming agent；Furthermore it is also fully utilized by byproduct ammonium chloride, makes to generate using ammonium chloride evaporation
70-80 DEG C of distilled water biruea is washed, by improving production efficiency to hydrochloric acid and hydrazine hydrate concentrate, reduce subsequent
The energy consumption of evaporation.For this technique compared with tradition ADC foaming agent producing process, the production cost of product reduces 30%.
Size distribution using above-mentioned process conditions production ADC foaming agent is measured using laser particle size analyzer, measures production
The granularity of product is divided into scope control between 0.01-12 μm, and average grain diameter can reach 2 μm, specific test data such as the following table 1
It is shown.And the common foaming agent particle size distribution of traditional equipment production is 0.01-40 μm, average particle size distribution is 12-15 μm.
The foaming agent product dispersibility of even particle size distribution is also preferable, provides safeguard for the steady production of downstream product.
1 size distribution table of table
Finally it should be noted that the foregoing is only a preferred embodiment of the present invention, it is not intended to restrict the invention,
Although the present invention is described in detail referring to the foregoing embodiments, for those skilled in the art, still may be used
To modify to technical solution documented by previous embodiment or equivalent replacement of some of the technical features.It is all
Within the spirit and principles in the present invention, any modification, equivalent replacement, improvement and so on should be included in guarantor of the invention
Within the scope of shield.
Claims (8)
- The agent producing process 1. a kind of ADC foams, which comprises the steps of:(1) it is condensed process, the hydrazine hydrate after urea and evaporation and concentrating is dissolved in condensation according to the ratio that mass ratio is 2.5:1 The hydrochloric acid of oxidation operation recycling is added in kettle, and the pH value of urea hydrazine hydrate solution is adjusted to 4.5-6.0, adjusts condensation kettle heating Solution is warming up to 100-120 DEG C with the speed of 1-3 DEG C/min by device, and constant temperature carries out condensation reaction 400-600min；(2) biruea refining step, after urea hydrazine hydrate solution completes condensation reaction in condensation kettle, by reaction solution in filter press In be filtered, obtain biruea solid particle, biruea solid particle washed in filter press using 75-85 DEG C of hot water, Washing to the pH value of cleaning solution is 7 ± 0.2；(3) the biruea solid particle for completing washing and water are added to oxygen according to the ratio that solid-to-liquid ratio is 1:2-3 by oxidation operation Change in kettle, halide salt is added as catalyst, while surfactant is added, chlorine is passed through into solution and is reacted, aoxidize It is shifted in kettle coil pipe using the heat that chilled brine generates reaction, makes reaction temperature control at 40 DEG C or less；Work as the extent of reaction When reaching 95% or more, it is added urea into reaction solution, the mass ratio of urea and reaction solution is 1:800-1000；(4) ADC foaming agent refining step is finally rinsed with water by the reaction solution of oxidation operation output after filtration washing step by step It is dry 6.5 or more to pH value, it is dry after ADC foaming agent enter after airslide disintegrating mill is crushed, is classified to get to ADC Product；(5) biruea filtrated stock recovery process, by step (2) filtrated stock and washing water carry out it is cooling, precipitate, union II Urea is deposited in below filtrate receiver, enters step (3) after precipitating biruea is again passed by washing, supernatant liquor is through triple effect evaporator By-product ammonium chloride is obtained after evaporation；(6) ADC foaming agent filtrated stock recovery process, the reaction solution filtrated stock that oxidation operation in step (4) is exported is through band Filter washs step by step concentration, obtains the hydrochloric acid that concentration is 20%-30%, stores into head tank, for the adjustment in step (1) Urea hydrazine hydrate solution pH value.
- The agent producing process 2. ADC as described in claim 1 foams, which is characterized in that water after evaporation and concentrating in the step (1) The concentration for closing hydrazine is 6%-20%.
- The agent producing process 3. ADC as described in claim 1 foams, which is characterized in that the halide salt catalysis in the step (3) Agent is one of sodium chloride, sodium bromide, ammonium bromide.
- The agent producing process 4. ADC as described in claim 1 foams, which is characterized in that the surfactant in the step (3) For cyclic amine compound or derivatives thereof.
- The agent producing process 5. ADC as described in claim 1 foams, which is characterized in that surfactant in the step (3) The mass ratio of additive amount and biruea solid particle aqueous solution is 0.01-0.1:100.
- The agent producing process 6. ADC as described in claim 1 foams, which is characterized in that the stills for air blowing in the step (3) use 2-5 layers of propeller agitator are provided with flow-stopping plate in stills for air blowing internal side wall.
- The agent producing process 7. ADC as described in claim 1 foams, which is characterized in that air-flow crushing described in the step (4) Machine is fluidized bed airflow pulverizer, and the minimum grain size of crushing is 1-2 μm.
- The agent producing process 8. ADC as claimed in claim 7 foams, which is characterized in that in the fluidized bed airflow pulverizer It is also equipped with cyclone separator.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114890919A (en) * | 2022-06-01 | 2022-08-12 | 宁夏日盛高新产业股份有限公司 | Production method of ADC foaming agent |
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