CN101780965A - Method for preparing sodium carbonate and ammonium chloride by utilizing melamine and tail gas of alcohol - Google Patents
Method for preparing sodium carbonate and ammonium chloride by utilizing melamine and tail gas of alcohol Download PDFInfo
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- CN101780965A CN101780965A CN200910138312A CN200910138312A CN101780965A CN 101780965 A CN101780965 A CN 101780965A CN 200910138312 A CN200910138312 A CN 200910138312A CN 200910138312 A CN200910138312 A CN 200910138312A CN 101780965 A CN101780965 A CN 101780965A
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- ammonium chloride
- ammonia
- liquid
- tail gas
- alcohol
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- 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
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
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- Y02P20/133—Renewable energy sources, e.g. sunlight
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Abstract
The invention discloses a novel alkali preparing method for preparing sodium carbonate and ammonium chloride by utilizing melamine and tail gas of biological alcohol. In the method, the melamine and the tail gas of the biological alcohol are fully utilized to replace synthetic ammonia and the circulating flow of once salting, twice ammonia absorption and once carbonatation is adopted. Compared with a conventional alkali preparing method, the novel alkali preparing method has the characteristics of simple production process, short flow and the like, and meets the national requirements of renewable energy sources; the sodium carbonate is produced by using byproducts of two industries as raw materials, so that the emission of greenhouse gas is reduced, the aim of two-way treatment of the tail gas of two industries of the melamine and alcohol is fulfilled, and double win of two industries on environmental and economic benefits is realized; and as the synthetic ammonia is saved and the cost of the sodium carbonate and the ammonium chloride is lower than that of a united alkali method by over 3.5 percent, the novel alkali preparing method has less equipment investment, high benefit and simple operation control.
Description
Technical field
The present invention relates to a kind of method of producing soda ash, ammonium chloride, this method makes full use of trimeric cyanamide and biological tail gas of alcohol substitutes synthetic ammonia, economy, environmental protection.
Technical background
Over past ten years, what attract people's attention most in the great number of issues of global environment is the problem that the earth warms gradually, i.e. Greenhouse effect.Carbonic acid gas is a kind of greenhouse gases, cause global warming, environment and society are caused negative influence widely, as sea level rise, living species extinction, farm output descend, biological extensive migration etc., discharging therefore how to control greenhouse gases has caused worldwide extensive concern.And in trimeric cyanamide, biological Alcohol Production process, can produce a large amount of tail gas (CO
2), the comprehensive utilization of its tail gas at home and abroad is a difficult problem all the time, has hindered the development scale of its industry.In addition, the comprehensive utilization of tail gas is directly connected to the problems such as investment, production cost and environment protection of industry.
Summary of the invention
Technical problem to be solved by this invention be solved trimeric cyanamide, biological tail gas of alcohol comprehensive treating process utilizes problem, responded the requirement of country's " renewable energy source ", with the by product of two industries as raw material, carry out the production of soda ash, reduce the discharging of greenhouse gases, reached the purpose of trimeric cyanamide and two industry tail gas of alcohol two-way treatment.
The production method that the present invention utilizes melamine tail gas and biological tail gas of alcohol to produce soda ash, ammonium chloride, it can make by following step:
One, the preparation of soda ash:
(1) female II liquid will absorb from the tail gas 60～70% that the Melamine Production device produces by high-order ammonia absorber, and through being stored in the ammonia II bucket behind settler, the water cooler, high-order ammonia absorber should vertically be installed, the height on its relative ground is more than 30 meters, just have greater than the 0.3MPa static pressure and be converted into the potential energy that liquid level has more than 30 meters, it is very fast to make that liquid descends, and causes the negative pressure-pumping gas ammonia in high-order ammonia absorber.Because the solubleness of ammonia is big, gas ammonia constantly is absorbed, and the pressure of gas ammonia is reduced.The chemical formula that female II liquid is inhaled ammonia is as follows:
NH
3(g)+H
2O(l)＝NH
4OH(aq)+34780J/mol
H
2O(l)+CO
2(g)＝H
2CO
3(aq)+20152J/mol
2NH
4OH(aq)+H
2CO
3(aq)＝(NH
4)
2CO
3(aq)+2H
2O(l)+73836J/mol
Owing to melamine tail gas temperature height, add the reaction heat of above-mentioned reaction, make its temperature raise, before entering the system washing tower (for removing CO2), to cool off with water cooler;
(2) CO in the alcoholic fermentation process
2Growing amount be 95.5% (massfraction) of alcohol output in theory.The actual CO that can reclaim in step fermentative production
2Be 50%～70% of theoretical yield, and when adopting the mode of continuously fermenting to produce, because in airtight fully equipment, so CO
2Almost can all reclaim, and purity can reach 99.0%～99.5%.With this part CO
2, through purify, the cooling back is mixed into compressor with purification furnace gas from the weight alkali calcining stove, boosts to 0.25～0.4MPa, enter then bottom the system washing tower (for removing CO2), as to CO in the melamine tail gas
2Insufficient replenishing;
(3) ammonia II liquid is sent into system washing tower (for removing CO2) top by ammonia II pump through interchanger, carries out carburizing reagent absorption CO with the compressed gas counter current contact that compressor is sent here
2, produce NaHCO
3Crystallization, this reaction are thermopositive reaction, make system washing tower (for removing CO2) middle part temperature raise.The tower Lower Half is lowered the temperature through water cooler, makes more NaHCO
3Crystallization is separated out, and absorbs more CO simultaneously
2, NaHCO
3Crystallization is grown up gradually, and unabsorbed carbonic acid gas and ammonia enter secondary tower bottom, comes out through gas-liquid separator from the top, after the ammoniated brine of carrying secretly is separated, delivers to secondary tower or as the wash water of vacuum filter, the gas emptying after the separation;
(4) the heavy alkali slurry that comes out from the system washing tower (for removing CO2) leans on and goes into carbonization stiff device from baric flow, obtains big and heavy alkali through behind the vacuum filter again, makes soda ash after the calcining, and filtrate and stiff device clear liquid are sent to the ammonium chloride preparation process as female I liquid.
Two, the preparation of ammonium chloride
(1) female I liquid will absorb from the tail gas 30～40% that the Melamine Production device produces by high-order ammonia absorber, and enter in the hot ammonia I bucket, high-order ammonia absorber should vertically be installed, the height on its relative ground is more than 30 meters, just have greater than the 0.3MPa static pressure and be converted into the potential energy that liquid level has more than 30 meters, it is very fast to make that liquid descends, and causes the negative pressure-pumping gas ammonia in high-order ammonia absorber.Because the solubleness of ammonia is big, gas ammonia constantly is absorbed, and the pressure of gas ammonia is reduced.Female I liquid suction ammonia react formula is as follows:
NH
3(g)+H
2O(l)＝NH
4OH(aq)+34780J/mol
H
2O(l)+CO
2(g)＝H
2CO
3(aq)+20152J/mol
2NaHCO
3(aq)+2NH
4OH(aq)＝Na
2CO
3(aq)+NH
4COONH
2(aq)+3H
2O(l)+60769J/mol
(NH
4)
2CO
3(aq)+NH
4OH(aq)＝NH
4COONH
2(aq)+2H
2O(l)+30362.4J/mol
NH
4COONH
2(aq)+2H
2O(l)＝(NH
4)
2CO
3(aq)-792.4J/mol
Above-mentioned reaction is reversible reaction, after female I liquid is inhaled ammonia, and some CO in the tail gas
2Be absorbed to generate (NH
4)
2CO
3, temperature is increased to 47～52 ℃ by 35～40 ℃, and this temperature is higher about 5 ℃ than normal temps, mainly is because the melamine tail gas temperature is higher and the cause of reaction heat.
(2) with pump ammonia I liquid is sent into interchanger and carry out heat exchange, interchanger is provided with 6 altogether, and wherein preceding two is watercooler, all the other 4 is the interchanger with female II heat exchange, after the cooling, after the crystallization stagnation point of its temperature near ammonium chloride, flow into the crystallization of carrying out ammonium chloride in the cool crystallizer;
(3) crystallization of ammonium chloride is finished by the cold analysis and the two portions of saltouing, earlier ammonia I liquid is sent into cool crystallizer, with from enter in the outer cooler circulating mother liquor on the distributor box flow into cool crystallizer in answer in the circulation tube, come downwards at the bottom of the crystallizer, turning back is upward through outstanding slurry layer again, make crystal growth, and the ammonium chloride degree of supersaturation in the solution disappears thereupon also, circulation so again and again, the crystal after the growth takes out through the magma pipe.Half female II liquid in cool crystallizer after the cold analysis, by going into the ingress, circulation tube top, center of salting-out crystallizer from baric flow, borrow the driving of propeller pump in the circulation tube of center, to flow downward, the desalinization of soil by flooding or leaching and filtrate add at the middle part of center circulation tube, magma flows out in the crystallizer bottom, magma section through suspending, settling section, enter the top inlet of center circulation tube again, the desalinization of soil by flooding or leaching constantly dissolving like this with the circulation of solution, common-ion effcet makes ammonium chloride constantly separate out, grow up, the magma after the growth flows into the stiff device of saltouing by take-off pipe, and its clear liquid and salting-out crystallizer supernatant liquor are female II liquid, flow in female II bucket, after the interchanger heat exchange, return the preparation process of soda ash;
(4) the effusive magma of stiff device of saltouing, flow in the center circulation tube in the cool crystallizer, in cold analysis stiff device, further be thickened to whizzer and separate, isolate ammonium chloride, cold analysis stiff clear liquid and whizzer filtrate overflow to filtrate tank, with being pumped into salting-out crystallizer center circulation tube.
Novel system alkali method of producing soda ash, ammonium chloride with trimeric cyanamide and biological tail gas of alcohol of the present invention, it is characterized in that: the β value in the ammonia II liquid generally is controlled between 1.01～1.08.
Described novel system alkali method of producing soda ash, ammonium chloride with trimeric cyanamide and biological tail gas of alcohol, it is characterized in that: the α value in the ammonia I liquid generally is controlled between 2.1～2.4.
Described novel system alkali method of producing soda ash, ammonium chloride with trimeric cyanamide and biological tail gas of alcohol, it is characterized in that: the γ value in female II liquid generally is controlled at more than 1.5.
This trimeric cyanamide and the biological tail gas of alcohol of utilizing provided by the present invention produced soda ash, the novel system alkali method of ammonium chloride, it is to utilize trimeric cyanamide, biological tail gas of alcohol substitutes synthetic ammonia, adopt once with salt, inhale the circulation process of an ammonia and a carbonating twice, compare with traditional system alkali method, it is simple to have production technique, characteristics such as flow process is short, this method with the tail gas of two industries as raw material, carry out the production of soda ash, reduced the discharging of greenhouse gases, the waste gas utilization that is two industries has found good outlet, reach the purpose of two industry tail gas two-way treatments, realized two doulbe-sides' victorys of industry on environmental benefit and economic benefit.
Description of drawings
Fig. 1 is that the present invention utilizes trimeric cyanamide and biological tail gas of alcohol to produce the novel system alkali method process flow diagram of soda ash, ammonium chloride.
Embodiment
With reference to accompanying drawing, at first introduce the preparation part of soda ash: 60%～70% of the tail gas that will produce from Melamine Production device 1 is produced ammonia II liquid and is stored in the ammonia II bucket 4 through the female II liquid absorption of high-order ammonia absorber 3 usefulness, its high-order ammonia absorber should vertically be installed, the height on its relative ground is more than 30 meters, and the β value in the ammonia II liquid generally is controlled between 1.01～1.08, sends into carbonating tower 7 more earlier after supercooler 6 coolings with ammonia II pump 5; Carbonic acid gas from biological Alcohol Production device 2 by-products, as replenishing to carbonic acid gas in the tail gas is insufficient, the carbonic acid gas of by-product is through purifying, enter compressor 13a after the cooling and boost to 0.25～0.4MPa, purify the compressed machine 13b of furnace gas from soda ash calcining furnace 14 simultaneously and boost to 0.25～0.4MPa, enter the bottom of carbonating tower 7 then, utilize ammonia II liquid in carbonating tower 7, to absorb carbonic acid gas in the gas, enter a pair tower 8 from the bottom from carbonating tower 7 tail gas discharged, absorb wherein a spot of ammonia and carbonic acid gas, purified gas passes through steam separator 9 back emptying up to standard again; The heavy alkali magma that comes out from carbonating tower 7 leans on from being depressed into stiff device 10, flowing into continous way then circles round in the alkali groove of vacuum filter 11, after the filter filtration, obtain big and heavy alkali sent for calcination stove 14 through calcine soda ash, filtered liquid is sent to the ammonium chloride preparation process as female I liquid through pump 15 and makes absorption liquid.
Be the preparation of ammonium chloride below: will absorb from the tail gas 30～40% that the Melamine Production device produces by high-order ammonia absorber 16 with female I liquid, and enter in the hot ammonia I bucket 17, high-order ammonia absorber 16 should vertically be installed, the height on its relative ground is more than 30 meters, after female I liquid is inhaled ammonia, temperature is increased to 47～52 ℃ by 35～40 ℃, and female I liquid should satisfy the α value and generally be controlled between 2.1～2.4; Hot ammonia I liquid is sent into interchanger and female II liquid carries out heat exchange with ammonia I pump 18, interchanger is provided with 6 altogether, wherein preceding two is watercooler 19, all the other 4 is the interchanger 20 with the heat exchange of female II liquid, cooled ammonia I liquid temp is near the crystallization stagnation point of ammonium chloride, enter cool crystallizer 22 pipe cores after metering, play to distribute at the bottom of the crystallizer with the circulating mother liquor one of outer cooler 21 and rise, cool crystallizer top mother liquor is outside propeller pump is sent in the cooler 21 bottom tubulations, and the liquefied ammonia heat exchange is lowered the temperature and the generation degree of supersaturation between pipe, the circulating mother liquor that is hypersaturated state follows also from the top aggregate groove, and pipe returns the crystallizer bottom through the center, by crystallization slurry layer its saturation ratio that disappears, impel crystallization to generate and growth, separate out ammonia chloride crystal so continuously, after in cool crystallizer, separating out a part, the overflow of cool crystallizer clear liquid is to salting-out crystallizer 23, borrow the driving of propeller pump in the circulation tube of center, to flow downward, distributing rises and progressively dissolve sodium-chlor separates out ammonia chloride crystal simultaneously, and make qualified female II liquid and flow into female II bucket 27, female II liquid arrives absorption after delivering to the interchanger heat exchange with pump 28, the ammonium chloride magma that is deposited at the bottom of female II liquid bucket is delivered to pump 29 in the center circulation tube of salting-out crystallizer 23, reclaims ammonium chloride wherein; Magma is fetched into the stiff device 25 of saltouing in the salting-out crystallizer, the clear liquid overflow is to female II bucket, the ammonium chloride magma of the stiff of saltouing device bottom, flow in the cool crystallizer 22, behind cold analysis stiff device 24 thickening together, flow out to whizzer 26 from the bottom and filter, isolate ammonium chloride, the supernatant liquor of cold analysis stiff device 24 enters filtrate tank 30 with the filtrate of whizzer 26, sends salting-out crystallizer 23 back to pump 31.
Claims (4)
1. utilize trimeric cyanamide and tail gas of alcohol to produce the production method of soda ash, ammonium chloride
It is characterized in that it can make by following step:
One, the preparation of soda ash:
(1) female II liquid will absorb from the tail gas 60～70% that the Melamine Production device produces by high-order ammonia absorber, and is stored in behind settler, water cooler in the ammonia II bucket, and high-order ammonia absorber should vertically be installed, and the height on its relative ground is more than 30 meters;
(2) the by product CO that obtains from biological Alcohol Production device
2, as to CO in the melamine tail gas
2Insufficient additional, the CO of biological alcohol by-product
2Through purify, the cooling back is mixed into compressor with purification furnace gas from the weight alkali calcining stove, boosts to 0.25～0.4MPa, enter then bottom the system washing tower (for removing CO2);
(3) with pump ammonia II liquid is sent into system washing tower (for removing CO2) top system alkali, the remaining gas mixture that comes out from the system washing tower (for removing CO2) enters secondary tower, unabsorbed carbonic acid gas and ammonia enter the secondary tower bottom, carry out the pre-carbonization of secondary tower, again through gas-liquid separator, after the ammoniated brine carried secretly separated, deliver to secondary tower or as the wash water of vacuum filter, the gas emptying after the separation;
(4) the heavy alkali slurry that comes out from the system washing tower (for removing CO2) leans on and goes into carbonization stiff device from baric flow, obtains big and heavy alkali through behind the vacuum filter again, makes soda ash after the calcining, and filtrate and stiff device clear liquid are sent to the ammonium chloride preparation process as female I liquid.
Two, the preparation of ammonium chloride
(1) female I liquid will absorb from the tail gas 30～40% that the Melamine Production device produces through high-order ammonia absorber, and enter in the hot ammonia I bucket, high-order ammonia absorber should vertically be installed, and the height on its relative ground is more than 30 meters, after female I liquid was inhaled ammonia, temperature was increased to 47～52 ℃ by 35～40 ℃;
(2) with pump ammonia I liquid is sent into interchanger and carry out heat exchange, interchanger is provided with 6 altogether, wherein preceding two is watercooler, all the other 4 is the interchanger with female II heat exchange, after the cooling, its temperature flows in the ammonia II bucket after near the crystallization stagnation point of ammonium chloride, and then with being pumped to the crystallization that crystallizer carries out ammonium chloride;
(3) crystallization of ammonium chloride is finished by the cold analysis and the two portions of saltouing, earlier ammonia I liquid is sent into cool crystallizer, after decrease temperature crystalline is separated out a part of ammonium chloride, overflow is to salting-out crystallizer again, further separate out ammonium chloride through saltouing, the ammonium chloride suspension that takes out from the salting-out crystallizer bottom enters the stiff device, through the centrifugal ammonium chloride finished product that gets of whizzer; Filtrate is sent salting-out crystallizer back to, and the salting-out crystallizer supernatant liquor is female II liquid, and female II liquid enters high-order ammonia absorber and absorbs melamine tail gas, forms circulation;
(4) the effusive magma of stiff device of saltouing, flow in the center circulation tube in the cool crystallizer, in cold analysis stiff device, further be thickened to whizzer and separate, isolate ammonium chloride, whizzer filtrate and cold analysis stiff device clear liquid overflow to filtrate tank, again with being pumped into salting-out crystallizer center circulation tube.
2. according to the described novel system alkali method of producing soda ash, ammonium chloride with trimeric cyanamide and biological tail gas of alcohol of claim 1, it is characterized in that: the β value in the ammonia II liquid generally is controlled between 1.01～1.08.
3. according to the described novel system alkali method of producing soda ash, ammonium chloride with trimeric cyanamide and biological tail gas of alcohol of claim 1, it is characterized in that: the α value in the ammonia I liquid generally is controlled between 2.1～2.4.
4. according to the described novel system alkali method of producing soda ash, ammonium chloride with trimeric cyanamide and biological tail gas of alcohol of claim 1, it is characterized in that: the γ value in female II liquid generally is controlled at more than 1.5.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910138312A CN101780965A (en) | 2009-04-29 | 2009-04-29 | Method for preparing sodium carbonate and ammonium chloride by utilizing melamine and tail gas of alcohol |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910138312A CN101780965A (en) | 2009-04-29 | 2009-04-29 | Method for preparing sodium carbonate and ammonium chloride by utilizing melamine and tail gas of alcohol |
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|---|---|
| CN101780965A true CN101780965A (en) | 2010-07-21 |
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|---|---|---|---|
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105698427A (en) * | 2016-02-15 | 2016-06-22 | 赵祥海 | Device and method for refrigerating and cooling lithium bromide at crystallization working station in combined-soda Process soda ash production process and cleaning hot ammonia I mother liquor of external cooler |
| CN105984887A (en) * | 2015-02-25 | 2016-10-05 | 鲁西化工集团股份有限公司 | Melamine-tail-gas utilization technology |
| CN106276982A (en) * | 2016-10-19 | 2017-01-04 | 中盐昆山有限公司 | Soda and sociation center novel environment friendly circulation technology system and method |
| CN107585778A (en) * | 2017-10-15 | 2018-01-16 | 赵祥海 | Salting-out crystallizer outer loop cool-down method in procedure of producing soda under joint alkaline process |
-
2009
- 2009-04-29 CN CN200910138312A patent/CN101780965A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105984887A (en) * | 2015-02-25 | 2016-10-05 | 鲁西化工集团股份有限公司 | Melamine-tail-gas utilization technology |
| CN105698427A (en) * | 2016-02-15 | 2016-06-22 | 赵祥海 | Device and method for refrigerating and cooling lithium bromide at crystallization working station in combined-soda Process soda ash production process and cleaning hot ammonia I mother liquor of external cooler |
| CN106276982A (en) * | 2016-10-19 | 2017-01-04 | 中盐昆山有限公司 | Soda and sociation center novel environment friendly circulation technology system and method |
| CN107585778A (en) * | 2017-10-15 | 2018-01-16 | 赵祥海 | Salting-out crystallizer outer loop cool-down method in procedure of producing soda under joint alkaline process |
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Open date: 20100721 |