CN102641657A - Method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas - Google Patents
Method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas Download PDFInfo
- Publication number
- CN102641657A CN102641657A CN2011100407955A CN201110040795A CN102641657A CN 102641657 A CN102641657 A CN 102641657A CN 2011100407955 A CN2011100407955 A CN 2011100407955A CN 201110040795 A CN201110040795 A CN 201110040795A CN 102641657 A CN102641657 A CN 102641657A
- Authority
- CN
- China
- Prior art keywords
- ammonium salt
- ammonia
- reaction
- tail gas
- tourie
- 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.)
- Pending
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
Landscapes
- Seasonings (AREA)
Abstract
The invention relates to a method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas, and comprises the following steps: letting ammonia-containing tail gas produced after production of ammonium salt get into a shower nozzle pipeline installed in a reaction pot; slowly opening a valve of the shower nozzle type nozzle; introducing ammonia gas-containing tail gas into the bottom portion of an absorption reaction pot containing stock solution for producing ammonium salt; controlling flow of ammonia gas entered into the reaction absorption pot, which further reacts with acid in the original reaction vessel for generating ammonium salt; condensing by a storage tank, separating, drying, fragmenting and packing finished product. The invention has the advantages that: 1) ammonia-containing tail gas discharged in the ammonium salt production process is reduced to the minimum which is green and environmental protection for meeting the nation prescribed discharge requirement; 2) high investment of traditional absorption equipment is minimized, and energy consumption in the absorption process is reduced; 3) the ammonia gas after absorption can be used as raw material with 10-14% increased output; 4) the absorbing capacity and absorption efficiency of the tail gas ammonia are increased to 90% or above.
Description
Technical field:
The present invention relates to a kind of production method of ammonium salt, produce the ammonia-containing exhaust discharging and utilize it to improve the method for ammonium salt output more specifically to a kind of ammonium salt of keeping under strict control.
Background technology:
As everyone knows, can discharge the tail gas that contains ammonia in the process of production ammonium salt,,, must ammonia be removed from being discharged into airborne ammonia according to the relevant regulations of environmental protection because ammonia can cause environmental problem.The technology of the tail gas method that when the pre-treatment ammonium salt is produced, produces has two kinds: a kind of is that low pressure ammonia and cooling fluid to be compressed are mixed into compressor compresses; Ammonia after compression gets in the gas-liquid separator; The high pressure ammonia gets in the ammonia storage tank from the gas-liquid separator top, and gas-liquid separator bottom cooling fluid is returned compressor cycle and used after cooling, filtration.Another kind of Diphenylamine Production And Ammonia Recovery Device, the aniline measuring tank port of export of device is connected in series with measuring pump, heat exchanger, heater, reactor, heat exchanger, low pressure separator, the gaseous phase outlet termination shell side entrance point of low pressure separator; The shell side port of export is connected in series with active carbon filter, ice maker; Another outlet termination low pressure separator liquid return hole end of shell side, the liquid phase outlet termination aniline distillation tower entrance point of low pressure separator, aniline distillation tower gaseous phase outlet termination heat exchanger shell pass entrance point; The shell side port of export one tunnel is connected in series with vacuum compression unit, active carbon filter, ice maker; Another road connects aniline measuring tank and aniline distillation tower, aniline distillation tower still liquid outlet termination diphenylamines rectifying column entrance point, diphenylamines rectifying column gaseous phase outlet termination cat head heat exchanger shell pass entrance point; Shell side outlet termination diphenylamines rectifying column and head tank entrance point; Rectifying column vacuumizes, and head tank connects nitrogen, head tank outlet termination slicer or comminutor entrance point.
Above-mentioned two kinds of methods to the weak point that ammonia reclaims existence are: two kinds of methods are the improvement to equipment, have the excessive problem of investment, are unfavorable for the industrialization of product, and also too harsh for the requirement of equipment.In addition; More than two kinds of recovery methods need under hyperbaric environment, move; And run through the whole recovery process, well imagine, no matter the method that therefore above two kinds of ammonias reclaim is all to have caused huge waste at cost or on energy consumption for the waste of energy consumption.The quality of compressor and the use of pressure-resistant material have certain danger in the process that above two kinds of ammonias reclaim; In removal process, need constantly pressure to be regulated; If misoperation will produce potential safety hazard, for example blast; Safety issue is difficult to go beyond, and therefore needs the resistance to pressure of pressure-resistant equipment in the exercise due diligence removal process and the quality problems of compressor.More than the recovery liquid that reclaims of two kinds of ammonias all to adopt water be that absorption liquid or alkali are absorption liquid; Because these two kinds of absorbing materials are single constituent; The inevasible saturated conditions that has in absorption process, if if reach capacity degree, overflowing or leakage situation then can appear in the ammonia that does not then have to have absorbed; The ammonia that has absorbed also can produce and decompose because of rising or other factors of temperature in the process of placing.Therefore the method for these two kinds of ammonias absorptions is a large amount of for the use of absorption liquid, also need carry out technological input for the preservation after absorbing, and corresponding cost also can improve greatly.Do not conform to enterprise reducing production costs of stressing.
Summary of the invention:
The objective of the invention is to provide the ammonium salt of keeping under strict control of a kind of low power consuming, low cost, work simplification, the no hidden danger of safety to produce the ammonia-containing exhaust discharging and utilize it to improve the method for ammonium salt output to the prior art weak point.
The objective of the invention is to realize through following measure: a kind of ammonium salt of keeping under strict control is produced the ammonia-containing exhaust discharging and is utilized it to improve the method for ammonium salt output, and its special character is: step is following:
Step 1, will produce and discharge the tail gas that contains ammonia behind the ammonium salt and be introduced directly into and fill in the reaction tourie of producing ammonium salt stoste, the gas outlet in the reaction tourie is seedpod of the lotus head;
Step 2, slowly open the valve of control shower nozzle gas output, the tail gas that will contain ammonia slowly discharges from the bottom of reaction tourie;
Step 3, control get into the flow that the reaction tourie contains ammonia, are lower than 15m
3/ hour, the reaction time is 6~8 hours, when when the outside pH meter that shows of reaction tourie is 5~7, stops reaction, the valve of closing control shower nozzle gas output;
Step 4, open the bottom valve of reaction tourie, emit reacted ammonium salt solution and make it get into storage tank to concentrate;
Step 5, the ammonium salt concentrated solution after concentrating are put into centrifuge and are separated, and centrifuge speed is 1500r/min, time 30min;
Step 6, warp oven dry again, the vacuum drying temperature is 40~80 ℃
Step 7, broken ammonium salt raw powder, the packed products of getting.
The valve of slowly opening shower nozzle of said step 2 is for only needing 1/4th sizes of Open valve, when feeling to have the sensation of air-blowing bubble, stops intensifying valve.
Compared with prior art; The ammonium salt of keeping under strict control that the present invention proposes is produced the ammonia-containing exhaust discharging and is utilized it to improve the method for ammonium salt output; Have following advantage: 1) environmental protection, discharge the tail gas that contains ammonia in the process of ammonium salt and reduce to minimum, meet the national regulation emission request; 2) reduce the high investment of traditional absorption equipment, reduced the energy consumption in the absorption process simultaneously; 3) ammonia after the absorption can be used as the raw material use, has reduced the preservation input to the ammonia after absorbing; 4) because the ammonium salt quality of the ammonium salt product quality of the corresponding acid that recycling produced through tail gas ammonia and production is consistent, output increase by 10%~14%; 5) uptake and the absorption efficiency of tail gas ammonia have been increased; Because feeding ammonia in the acid solution is the bend pipe of a band shower nozzle; Therefore can increase ammonia and sour contact area; Helping the carrying out that react, be merely 45%~60% with the absorptivity of traditional handicraft and compare, the present invention can reach >=and 90%; 6) under the constant situation of product quality, enlarged the output of the ammonium salt of respective acids.
Description of drawings:
Fig. 1 is the process chart of one embodiment of the invention.
The specific embodiment:
Below in conjunction with accompanying drawing the specific embodiment is elaborated:
Fig. 1 is the process chart of one embodiment of the invention.Among the figure, a kind of ammonium salt of keeping under strict control is produced the ammonia-containing exhaust discharging and is utilized it to improve the method for ammonium salt output, and its step is following:
Step 1, will produce and discharge the tail gas that contains ammonia behind the ammonium salt and be introduced directly into and fill in the reaction tourie of producing ammonium salt stoste, the gas outlet in the reaction tourie is seedpod of the lotus head.What this step was considered is: for reclaiming ammonia, then optimal absorption liquid is the stoste of project product, for example; Produce ammonium formate; The absorption liquid that uses then is formic acid solution, therefore in absorption process, just can not have saturated conditions, because the polarity of corresponding ammonium salt is similar with the polarity of ammonia; The character that in chemical reaction, has the polarity similar compatibility; Therefore the effect of the absorption ammonia of corresponding ammonium salt is more far better than the assimilation effect of the water of conventional method or alkali, and absorptivity can reach 95%, and traditional handicraft is merely 45%~60%.And for example, when producing ammonium citrate, the absorption liquid of tail gas uses citric acid; Reason is that the polarity of corresponding ammonium salt is similar with ammonia; In line with the principle of similar compatibility, adopt citric acid can improve the assimilation effect of ammonia as absorption liquid, increase absorptivity; Final absorptivity is 96%, and traditional handicraft is between 45%~60%.
Step 2, slowly open the valve of control shower nozzle gas output, the tail gas that will contain ammonia slowly discharges from the bottom of reaction tourie.The said valve of slowly opening control shower nozzle gas output is for only needing 1/4th sizes of Open valve, when feeling to have the sensation of air-blowing bubble, stops intensifying valve.Can guarantee that like this gas and acid carries out the sufficient reaction time, can not occur causing reaction not exclusively because regional ventilation is too fast during reaction.In this step gas is introduced the mode substantial progress of having compared with traditional handicraft; Original traditional handicraft is to do into straight-through discharge the in bend pipe feeding liquid level bottom with a straight tube or with straight tube; Form large sparkle one by one during discharge, large sparkle rises very soon and emerges, and can't reach ammonia and be absorbed to greatest extent; After using shower nozzle; Ammonia is refined as a plurality of small bubbles and slowly becomes the filament shape to extrude to a plurality of directions, can increase the contact area between ammonia and liquid like this, makes ammonia fully be absorbed and reacts.
Step 3, control get into the flow that the reaction tourie contains ammonia, are lower than 15m
3/ hour, the reaction time is 6~8 hours, when when the outside pH meter that shows of reaction tourie is 5~7, stops reaction, the valve of closing control shower nozzle gas output.Can not guarantee the quality of reacting under the situation of catalyst adding, accelerated reaction fully.
Step 4, the bottom valve of opening the absorption reaction jar are emitted reacted ammonium salt solution and are got into storage tank and concentrate.
Step 5, the ammonium salt concentrated solution after concentrating are gone into centrifuge and are separated, and centrifuge speed is 1500r/min, time 20min;
Step 6, again through vacuum drying, bake out temperature is 40~80 ℃.The too high meeting of temperature causes the decomposition of ammonium salt.
Step 7, broken ammonium salt raw powder, the packed products of getting.
Further explain below with embodiment:
Embodiment 1 is in the technological process of producing ammonium formate; Feed the ammonia that collect ammonium formate reaction back; Be introduced directly in the reaction tourie that fills production ammonium salt stoste, the gas outlet in the reaction tourie is seedpod of the lotus head, slowly opens the valve of control shower nozzle gas output; Control gets into the flow that the reaction tourie contains ammonia, and flow is 12m
3/ hour, include in the formic acid solution of formic acid with the reaction tourie and to react, react the observation pH value of solution 7 hours; When pH is in 6.5, stop reaction, material is placed storage tank concentrate; Put centrifugal 30min to the 1500r/min centrifuge afterwards, deliver to the vacuum drying chamber oven dry, temperature is 40 ℃; Oven dry gets final product, and the crushing packing finished product is accomplished preparation.Its technical indicator is listed in the following table.
Embodiment 2 is in the technological process of producing ammonium citrate; Feed the ammonia that collect ammonium citrate reaction back; Be introduced directly in the reaction tourie that fills production ammonium salt stoste, the gas outlet in the reaction tourie is seedpod of the lotus head, slowly opens the valve of control shower nozzle gas output; Control gets into the flow that the reaction tourie contains ammonia, and flow is 15m
3/ hour, include in the citric acid solution of citric acid with the reaction tourie and to react, reacted 6 hours; Observe pH value of solution, when pH is in 6.7, stop reaction; Material is placed storage tank concentrate, put centrifugal 30min to the 1500r/min centrifuge afterwards, deliver in the vacuum drying chamber and dry; Temperature is 65 ℃, and oven dry gets final product the crushing packing finished product.Accomplish preparation.Because so the stronger reaction time that needs for the absorption of ammonia of the polarity of citric acid also can shorten.Relatively listing in the following table of embodiment and conventional process techniques index.
Project name | Traditional handicraft | Embodiment 1 | Embodiment 2 |
Ammonia absorptivity (%) | 45~60% | 95% | 96% |
Ignition residue (%) | 0.01 | 0.01 | 0.008 |
The pH value | 5.75 | 5.62 | 5.60 |
Water-insoluble (%) | 0.002 | 0.001 | 0.0009 |
Chloride (%) | 0.0005 | 0.0005 | 0.0043 |
Nitrate (%) | 0.001 | 0.0008 | 0.0007 |
Phosphate (%) | 0.0005 | 0.00035 | .0.00043 |
Arsenic (%) | 0.00002 | 0.000007 | 0.00001 |
Iron (%) | 0.0002 | 0.0002 | .0.0002 |
Heavy metal (%) | 0.0005 | 0.0004 | 0.0003 |
Output | 100% | 110% | 114% |
Economic and social benefit:
The economic construction of China at present is in the period of a transition, turns to green economy, low-carbon economy from traditional industrial economy.Conventional industries economy is to be the economy of characteristic to destroy the ecological balance, the lot of consumption energy and resource, to damage health, is a kind of lossy economy.Green economy then is to safeguard environment for human survival, Reasonable Protection resource and the energy, to be of value to the economy that health is a characteristic, is a kind of balanced type economy.Traditional ammonia recovery method is comparatively typical conventional industries economy, uses the numerous and diverse absorption process of high pressure-resistant material and step, its power consumption, consuming time expensive be the bottleneck of puzzlement recovery.The tail gas recycle that contain ammonia and the utilization of the inventive method to discharging in the process of producing ammonium salt, the most directly benefit is that output increases by 10%~14%.The indirect benefit of the inventive method is more considerable: production cost does not have increase, and the absorption of ammonia need not to add new raw material, need not to set up huge deamination equipment yet, and the scrap build expense is limited.In addition; Aspect energy-saving and cost-reducing; Do not suppress because of not needing whole absorption process to add, the energy of the required consumption of this technology is merely 1/4th of traditional handicraft consumes energy in energy-saving and cost-reducing, in whole absorption process, has not both had to introduce also not have to produce to jeopardize safe step and link; And the absorptivity of ammonia improves and to reach more than 90%, and traditional handicraft is merely 45%~60%.Even more important thing is the discharging that ammonia has been controlled in strictness, and the natural environment of protecting the mankind to depend on for existence has been stepped major step.In brief; The present invention is directed to the problem that existing absorption techniques exists; Having researched and developed a kind of low power consuming, low cost, work simplification, environmental protection does not have the method that safety hazards, ammonium salt production tail gas recycle that absorption efficiency is higher are utilized, and has obtained same quality, the more ammonium salt of output.Economic aspect has been obtained obvious improvement rebuilding traditional industry.
More than combine embodiment to be described, the foregoing description is not construed as limiting the invention, and adopts the technical scheme that form obtained that is equal to replacement or equivalent transformation in every case, all drops within protection scope of the present invention.
Claims (2)
1. the ammonium salt of keeping under strict control is produced the ammonia-containing exhaust discharging and is utilized it to improve the method for ammonium salt output, it is characterized in that step is following:
Step 1, will produce and discharge the tail gas that contains ammonia behind the ammonium salt and be introduced directly into and fill in the reaction tourie of producing ammonium salt stoste, the gas outlet in the reaction tourie is seedpod of the lotus head;
Step 2, slowly open the valve of control shower nozzle gas output, the tail gas that will contain ammonia slowly discharges from the bottom of reaction tourie;
Step 3, control get into the flow that the reaction tourie contains ammonia, are lower than 15m
3/ hour, the reaction time is 6~8 hours, when when the outside pH meter that shows of reaction tourie is 5~7, stops reaction, the valve of closing control shower nozzle gas output;
Step 4, open the bottom valve of reaction tourie, emit reacted ammonium salt solution and make it get into storage tank to concentrate;
Step 5, the ammonium salt concentrated solution after concentrating are put into centrifuge and are separated, and centrifuge speed is 1500r/min, time 30min;
Step 6, warp oven dry again, the vacuum drying temperature is 40~80 ℃
Step 7, broken ammonium salt raw powder, the packed products of getting.
2. produce the ammonia-containing exhaust discharging and utilize it to improve the method for ammonium salt output according to the said ammonium salt of keeping under strict control of claim 1; It is characterized in that; The valve of slowly opening shower nozzle of said step 2 is for only needing 1/4th sizes of Open valve, when feeling to have the sensation of air-blowing bubble, stops intensifying valve.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2011100407955A CN102641657A (en) | 2011-02-18 | 2011-02-18 | Method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2011100407955A CN102641657A (en) | 2011-02-18 | 2011-02-18 | Method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas |
Publications (1)
Publication Number | Publication Date |
---|---|
CN102641657A true CN102641657A (en) | 2012-08-22 |
Family
ID=46654889
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN2011100407955A Pending CN102641657A (en) | 2011-02-18 | 2011-02-18 | Method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN102641657A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103877811A (en) * | 2014-02-25 | 2014-06-25 | 中盐安徽红四方股份有限公司 | Material conveying aeration ammonia-containing gas recovering system of combined-soda process device |
CN111214920A (en) * | 2018-11-26 | 2020-06-02 | 裴天锋 | High-efficient purifier in pig farm |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1062854A (en) * | 1990-12-29 | 1992-07-22 | 湖南省农药工业公司 | Hydrogen sulfide and ammonia process for recovering mixing gas |
US20070169628A1 (en) * | 2004-03-31 | 2007-07-26 | Daikin Industries, Ltd. | Gas purifier |
CN101143291A (en) * | 2006-09-13 | 2008-03-19 | 史选增 | Low-consumption high-quality ammonium sulfate fertilizer recovery wet ammonia process desulfurizing technology |
CN101531381A (en) * | 2009-04-23 | 2009-09-16 | 四川金圣赛瑞化工有限责任公司 | Method for producing ammonium nitrate by ammonium-containing waste gas |
CN101766953A (en) * | 2008-12-30 | 2010-07-07 | 江苏远洋化学有限公司 | Device for recovering tail gas containing ammonia |
-
2011
- 2011-02-18 CN CN2011100407955A patent/CN102641657A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1062854A (en) * | 1990-12-29 | 1992-07-22 | 湖南省农药工业公司 | Hydrogen sulfide and ammonia process for recovering mixing gas |
US20070169628A1 (en) * | 2004-03-31 | 2007-07-26 | Daikin Industries, Ltd. | Gas purifier |
CN101143291A (en) * | 2006-09-13 | 2008-03-19 | 史选增 | Low-consumption high-quality ammonium sulfate fertilizer recovery wet ammonia process desulfurizing technology |
CN101766953A (en) * | 2008-12-30 | 2010-07-07 | 江苏远洋化学有限公司 | Device for recovering tail gas containing ammonia |
CN101531381A (en) * | 2009-04-23 | 2009-09-16 | 四川金圣赛瑞化工有限责任公司 | Method for producing ammonium nitrate by ammonium-containing waste gas |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103877811A (en) * | 2014-02-25 | 2014-06-25 | 中盐安徽红四方股份有限公司 | Material conveying aeration ammonia-containing gas recovering system of combined-soda process device |
CN111214920A (en) * | 2018-11-26 | 2020-06-02 | 裴天锋 | High-efficient purifier in pig farm |
CN111214920B (en) * | 2018-11-26 | 2022-08-09 | 裴天锋 | High-efficient purifier in pig farm |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN105366653A (en) | Nitric acid production technology with double-pressurized method | |
CN101857246B (en) | Process method for co-producing ammonium bicarbonate by using coking plant waste | |
CN104748507B (en) | Treatment system for recovering chemical plant waste gas containing ammonia into liquid ammonia and treatment method thereof | |
CN106362548A (en) | Treating method of oxidized tail gas in process of manufacturing cyclohexanone with cyclohexane oxidation method | |
CN104208987B (en) | Device for recovering tail gas in a kind of urea ammonium nitrate solution production | |
CN103408467A (en) | Low-energy-consumption urea production technology and system adopting CO2 stripping method | |
CN102167412B (en) | High-efficiency composite urea waste liquid deep hydrolysis desorption tower | |
CN102641657A (en) | Method for strictly controlling discharge of ammonia-containing tail gas in the ammonium salt production and improving ammonium salt output using the tail gas | |
CN105236451A (en) | Method and apparatus for continuous conversion production of sodium nitrate | |
CN103755393B (en) | Device and method for co-producing potassium sulphate compound fertilizer from tripolycyanamide tail gas | |
CN202519043U (en) | Synthesis ammonia device | |
CN202829608U (en) | Urea deep-hydrolyzation gaseous-phase heat recovery system | |
CN103250696A (en) | Preparation method for high-concentration ethephon aqua | |
CN214829037U (en) | Device for producing dilute nitric acid by magnesium nitrate method | |
CN204301354U (en) | Warm heat-energy utilizing device in a kind of synthetic ammonia | |
CN204891274U (en) | Urea low pressure decomposition tower | |
CN104557615A (en) | System for synthesizing urea solution | |
CN204174133U (en) | A kind of device utilizing urea plant to reclaim melamine tail gas | |
CN109516932B (en) | Energy-saving reforming process system of urea device | |
CN203393072U (en) | Low-energy CO2 vaporizing extract process urea system | |
CN102351739B (en) | Urea granulation tail gas ammonia emission reduction technology and ammonia emission reduction device | |
CN203890067U (en) | Carbon dioxide purification device for producing urea | |
CN204125192U (en) | The useless time sodium recycle device of acetylene | |
CN203295398U (en) | Circulating device for preparing urea | |
CN205616822U (en) | Yellow water concentration and organic matter recovery unit |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20120822 |