CN109796029B - Preparation method of ammonium nitrate sulfate - Google Patents
Preparation method of ammonium nitrate sulfate Download PDFInfo
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- CN109796029B CN109796029B CN201910168718.4A CN201910168718A CN109796029B CN 109796029 B CN109796029 B CN 109796029B CN 201910168718 A CN201910168718 A CN 201910168718A CN 109796029 B CN109796029 B CN 109796029B
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Abstract
The invention relates to a preparation method of ammonium nitrate, which comprises the steps of introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, reacting to generate mixed solution containing ammonium nitrate and ammonium sulfate, carrying out gas-liquid separation by a flash separator, feeding the liquid into a stirring and mixing tank, adding diammonium hydrogen phosphate into the stirring and mixing tank, and uniformly stirring for a long time to form 1:1 type, 1:2 type or 1:3 type ammonium nitrate double salt; evaporating the reacted mixed slurry, and controlling the evaporation temperature and the vacuum degree; and (4) carrying out vacuum filtration on the evaporated slurry, returning the filtrate to the mixing tank to continuously participate in the reaction, and drying the filter cake to obtain a finished product ammonium nitrate sulfate. Ammonium nitrate and ammonium sulfate generated in the tubular reactor are subjected to chemical reaction in an aqueous solution, so that ammonium nitrate and ammonium sulfate double salts in various forms can be generated, and the ammonium nitrate and ammonium sulfate double salts are stable in chemical properties and are not easy to agglomerate.
Description
Technical Field
The invention relates to the technical field of fertilizer production, in particular to a preparation method of ammonium nitrate sulfate.
Background
Ammonium nitrate sulfate is a widely used nitrogen fertilizer, contains two elements of nitrogen and sulfur, the nitrogen element has two forms of ammonium nitrogen and nitrate nitrogen, is especially suitable for various crops which like nitrate nitrogen and sulfur, such as cruciferae, allium fistulosum and the like, is generally used as top dressing, can be applied to soil, and can also be applied to irrigation. Unlike ammonium sulfate, ammonium nitrate sulfate does not form obvious acidity in soil, is close to physiological neutral fertilizer, and has high nitrate nitrogen absorption rate and fertilizer efficiency faster than ammonium sulfate.
Ammonium nitrate is generally light yellow particles and is completely water-soluble, compared with ammonium nitrate, the ammonium nitrate has the characteristics of small hygroscopicity, stable chemical property, difficult caking, difficult combustion and explosion and the like, because ammonium nitrate and ammonium sulfate form stable double salts, the reported ammonium nitrate double salts comprise 1:1 type, 1:2 type and 1:3 type, wherein the 1:2 type ammonium nitrate is the most stable, in the traditional production method, liquid ammonium nitrate and solid ammonium sulfate are mixed according to a certain proportion and then are melted to form the ammonium nitrate, the mass concentration of the liquid ammonium nitrate is more than 99 percent, most of the formed ammonium nitrate is 1:1 type products, and a large amount of simple substance ammonium sulfate or ammonium nitrate is contained, so that the physical and chemical properties of the ammonium nitrate are still unstable, and the ammonium nitrate is easy to cake.
Disclosure of Invention
The invention aims to solve the technical problem of providing a preparation method of ammonium nitrate sulfate, which utilizes strong exothermic reaction of ammonia gas, nitric acid and sulfuric acid solution in a tubular reactor to generate mixed solution containing ammonium nitrate and ammonium sulfate, and the mixed solution is uniformly stirred and reacts for a long time under the action of diammonium hydrogen phosphate to generate 1:1 type, 1:2 type or 1:3 type ammonium nitrate sulfate.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a preparation method of ammonium nitrate sulfate comprises the following steps:
1) introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, reacting to generate mixed solution containing ammonium nitrate and ammonium sulfate, performing gas-liquid separation by a flash separator, introducing the liquid into a stirring and mixing tank, adding diammonium hydrogen phosphate into the stirring and mixing tank, and uniformly stirring for a long time to form ammonium nitrate double salt of 1:1 type, 1:2 type or 1:3 type or the combination thereof;
2) evaporating the reacted mixed slurry, and controlling the evaporation temperature and the vacuum degree;
3) and (4) carrying out vacuum filtration on the evaporated slurry, returning the filtrate to the mixing tank to continuously participate in the reaction, and drying the filter cake to obtain a finished product ammonium nitrate sulfate.
Preferably, in the step 1), the mass concentration of the nitric acid solution is 60-65%, and the mass concentration of the sulfuric acid solution is 90-98%.
Preferably, in the step 1), the ratio of the ammonia gas to the amount of the pure nitric acid and the pure sulfuric acid in the nitric acid and sulfuric acid solution is 3-4: 1-2:1.
Preferably, in the step 1), diammonium hydrogen phosphate is added into the stirring and mixing tank, and the ammonium nitrate solution comprises 50-65 parts by weight of ammonium sulfate and 0.0001-5 parts by weight of diammonium hydrogen phosphate.
Preferably, in step 1), the reaction time is stirred for 30 to 120 minutes.
Preferably, in the step 2), the evaporation temperature is controlled to be 160-200 ℃ and the vacuum degree is controlled to be 70-100 Kpa.
Preferably, in the step 3), the moisture content of the dried finished ammonium nitrate sulfate is not higher than 2%.
The invention provides a preparation method of ammonium nitrate sulfate, which has the following beneficial effects:
1. in the production of traditional ammonium nitrate sulfate, liquid ammonium nitrate with the mass concentration of more than 99 percent and solid ammonium sulfate are mixed in proportion, under the environment with extremely low moisture content, the ammonium nitrate and the ammonium sulfate are simply and physically mixed, and the stable double salt generated by chemical reaction is little;
2. compared with the traditional production method, the ammonia, the nitric acid and the sulfuric acid solution react in the tubular reactor, the generated heat is beneficial to the reaction of ammonium nitrate and ammonium sulfate to generate ammonium nitrate and ammonium sulfate double salt, the reaction rate and the yield are improved, the average yield of the double salt is more than 70 percent, and the traditional production method is adopted, the yield of the double salt is less than 10 percent and is basically 1:1 type double salt;
3. adding a certain amount of diammonium phosphate into the mixing tank, so that the aqueous solution is weakly alkaline, and the ammonium nitrate and ammonium sulfate complex salt is generated in a weakly alkaline environment; on the other hand, due to the existence of ammonium ions in the diammonium hydrogen phosphate, reverse decomposition of ammonium nitrate sulfate to ammonium sulfate and ammonium nitrate is effectively inhibited.
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FIG. 1 is a schematic view of the apparatus of the present invention;
wherein: the device comprises a nitric acid storage tank 1, a tubular reactor 2, a flash separator 3, a stirring mixing tank 4, a flash tank 5, a primary evaporator 6, a secondary evaporator 7, a high tower melting granulation device 9, a neutralization washing tower 8, a gas ammonia inlet pipe 21, a nitric acid inlet pipe 22, a sulfuric acid inlet pipe 23, an ammonium sulfate crystal discharge opening 41, a diammonium hydrogen phosphate discharge opening 42 and a medium-pressure steam inlet pipe 71.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited to the scope of the examples. These examples are intended to illustrate the invention only and are not intended to limit the scope of the invention.
Example 1
Introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, wherein the mass concentration of the nitric acid solution is 65%, the mass concentration of the sulfuric acid solution is 98%, and the mass ratio of the ammonia gas to the nitric acid to the pure sulfuric acid in the sulfuric acid solution is 4: 2:1, reacting to generate a mixed solution containing ammonium nitrate and ammonium sulfate, carrying out gas-liquid separation by a flash separator, feeding the liquid into a stirring and mixing tank, adding no diammonium hydrogen phosphate into the stirring and mixing tank, uniformly stirring the liquid in the mixing tank for 60 minutes, feeding the liquid into an evaporation system, controlling the evaporation temperature to be 180 ℃ and the vacuum degree to be 80Kpa, feeding the reaction slurry with most of water removed by evaporation into a vacuum belt filter for cooling and filtering to obtain an ammonium nitrate filter cake, finally drying to obtain an ammonium nitrate finished product, and returning the filtrate into the mixing tank to continuously participate in the reaction. The finished ammonium nitrate sulfate was subjected to X-ray diffraction (XRD) in wt.% and resulted in a yield of 22.82% of double salt, with a yield of 1:2 type double salt of 1.78%:
ammonium nitrate 56.91
Ammonium sulfate 19.07
1:1 type double salt 20.5
1:2 type double salt 1.78
1:3 type double salt 0.54
Water 1.2
Example 2
Introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, wherein the mass concentration of the nitric acid solution is 65%, the mass concentration of the sulfuric acid solution is 98%, and the mass ratio of the ammonia gas to the nitric acid to the pure sulfuric acid in the sulfuric acid solution is 4: 2:1, reacting to generate a mixed solution containing ammonium nitrate and ammonium sulfate, carrying out gas-liquid separation by a flash separator, feeding the liquid into a stirring mixing tank, uniformly stirring the liquid in the mixing tank for 60 minutes, feeding the liquid into an evaporation system, controlling the evaporation temperature to be 180 ℃ and the vacuum degree to be 80Kpa, feeding the reaction slurry subjected to evaporation to remove most of water into a vacuum belt filter for cooling and filtering to obtain ammonium nitrate filter cakes, finally drying to obtain ammonium nitrate finished products, and feeding the filtrate back into the mixing tank to continuously participate in the reaction. The finished ammonium nitrate sulfate was subjected to X-ray diffraction (XRD) in wt.%, resulting in 78.46% yield of the double salt, wherein the yield of the 1:2 type double salt was 55.06%:
ammonium nitrate 11.63
Ammonium sulfate 5.31
Phosphate 3.5
1:1 type double salt 12.2
Type 1:2 double salt 55.06
1:3 type double salt 11.2
Water 1.1
Example 3
Introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, wherein the mass concentration of the nitric acid solution is 65%, the mass concentration of the sulfuric acid solution is 98%, and the mass ratio of the ammonia gas to the nitric acid to the pure sulfuric acid in the sulfuric acid solution is 4: 2:1, reacting to generate a mixed solution containing ammonium nitrate and ammonium sulfate, carrying out gas-liquid separation by a flash separator, feeding the liquid into a stirring mixing tank, uniformly stirring 5% by mass of diammonium hydrogen phosphate in the mixing tank for 60 minutes, feeding the liquid into an evaporation system, controlling the evaporation temperature to be 180 ℃ and the vacuum degree to be 80Kpa, feeding the reaction slurry subjected to evaporation to remove most of water into a vacuum belt filter for cooling and filtering to obtain ammonium nitrate filter cakes, finally drying to obtain ammonium nitrate finished products, and feeding the filtrate back into the mixing tank to continuously participate in the reaction. The finished ammonium nitrate sulfate was subjected to X-ray diffraction (XRD) in wt.% with the following results, the yield of the double salt was 94.11%, wherein the yield of the 1:2 type double salt was 86.56%:
ammonium nitrate 0
Ammonium sulfate 0
Phosphate 4.89
1:1 type double salt 3.77
Type 1:2 double salt 86.56
1:3 type double salt 3.78
Example 4
Introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, wherein the mass concentration of the nitric acid solution is 65%, the mass concentration of the sulfuric acid solution is 98%, and the mass ratio of the ammonia gas to the nitric acid to the pure sulfuric acid in the sulfuric acid solution is 3: 1:1, reacting to generate a mixed solution containing ammonium nitrate and ammonium sulfate, carrying out gas-liquid separation by a flash separator, feeding the liquid into a stirring mixing tank, uniformly stirring the liquid in the mixing tank for 120 minutes, feeding the liquid into an evaporation system, controlling the evaporation temperature to be 170 ℃ and the vacuum degree to be 100Kpa, feeding the reaction slurry subjected to evaporation to remove most of water into a vacuum belt filter for cooling and filtering to obtain ammonium nitrate filter cakes, drying to obtain ammonium nitrate finished products, and feeding the filtrate back into the mixing tank to continuously participate in the reaction. The finished ammonium nitrate sulfate was subjected to X-ray diffraction (XRD) in wt.% and resulted in 80.78% yield of the double salt, with 9.2% yield of the 1:2 type double salt:
ammonium nitrate 10.29
Ammonium sulfate 4.62
Phosphate 3.21
1:1 type double salt 60.06
1:2 type double salt 9.2
1:3 type double salt 11.52
Water 1.1
Example 5
Introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, wherein the mass concentration of the nitric acid solution is 65%, the mass concentration of the sulfuric acid solution is 98%, and the mass ratio of the ammonia gas to the nitric acid to the pure sulfuric acid in the sulfuric acid solution is 3: 1:1, reacting to generate a mixed solution containing ammonium nitrate and ammonium sulfate, carrying out gas-liquid separation by a flash separator, feeding the liquid into a stirring and mixing tank, uniformly stirring the liquid in the mixing tank for 120 minutes, feeding the liquid into an evaporation system, controlling the evaporation temperature to be 170 ℃ and the vacuum degree to be 100Kpa, feeding the reaction slurry subjected to evaporation to remove most of water into a vacuum belt filter for cooling and filtering to obtain ammonium nitrate filter cakes, drying to obtain ammonium nitrate finished products, and feeding the filtrate back into the mixing tank to continuously participate in the reaction. The finished ammonium nitrate sulfate was subjected to X-ray diffraction (XRD) in wt.% and resulted in 94.04% yield of the double salt, wherein 7.76% yield of the 1:2 type double salt:
ammonium nitrate 0
Ammonium sulfate 0
Phosphate 4.96
1:1 type double salt 78.53
1:2 type double salt 7.76
1:3 type double salt 7.75
Example 6
The device adopted in the embodiments 1 to 5 comprises a nitric acid storage tank 1, wherein the nitric acid storage tank 1 is sequentially communicated with a tubular reactor 2, a flash separator 3, a stirring mixing tank 4, a flash tank 5, a primary evaporator 6, a secondary evaporator 7 and a high tower melting granulation device 9 through pipelines, and the nitric acid storage tank 1 is also sequentially communicated with a neutralization washing tower 8 and the stirring mixing tank 4 through pipelines.
Preferably, the tubular reactor 2 is provided with a gas ammonia inlet pipe 21, a nitric acid inlet pipe 22 and a sulfuric acid inlet pipe 23, and the stirring and mixing tank 4 is provided with an ammonium sulfate crystal discharge port 41 and a diammonium hydrogen phosphate discharge port 42.
Preferably, the flash separator 3 communicates with the neutralization scrubber 8 via a conduit.
Preferably, the secondary evaporator 7 is provided with a medium pressure steam inlet pipe 71, and the stirring mixing tank 4 is sequentially communicated with the flash tank 5, the primary evaporator 6 and the secondary evaporator 7 through pipelines.
Preferably, the neutralization scrubber 8 forms a circuit with the primary evaporator 6 through a pipe. Washing process steam of the neutralization washing tower 8 enters the primary evaporator 6 for utilization, and process steam condensate of the primary evaporator 6 enters the neutralization washing tower 8 for reuse.
The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. A preparation method of ammonium nitrate sulfate is characterized in that: the method comprises the following processes:
1) introducing ammonia gas, nitric acid and sulfuric acid solution into a tubular reactor, reacting to generate mixed solution containing ammonium nitrate and ammonium sulfate, performing gas-liquid separation by a flash separator, introducing the liquid into a stirring and mixing tank, adding diammonium hydrogen phosphate into the stirring and mixing tank, and uniformly stirring for a long time to form mixed slurry of ammonium nitrate and ammonium sulfate double salts of 1:1 type, 1:2 type or 1:3 type or a combination thereof;
2) evaporating the reacted mixed slurry, wherein the evaporation conditions are as follows: the temperature is 160 ℃ and 200 ℃, and the vacuum degree is 70-100 Kpa;
3) and (3) carrying out vacuum filtration on the evaporated slurry, returning the filtrate to the stirring and mixing tank to continuously participate in the reaction, and drying the filter cake to obtain the finished ammonium nitrate sulfate, wherein in the step 1), the mass concentration of the nitric acid solution is 60-65%, and the mass concentration of the sulfuric acid solution is 90-98%.
2. The method for preparing ammonium nitrate sulfate according to claim 1, wherein: in the step 1), the mass ratio of ammonia gas to nitric acid and sulfuric acid is 3-4: 1-2: 1;
in the step 1), diammonium hydrogen phosphate is added into a stirring and mixing tank, and the stirring and mixing tank contains 50-65 parts by weight of ammonium nitrate solution, 30-50 parts by weight of ammonium sulfate and 0.0001-5 parts by weight of diammonium hydrogen phosphate.
3. The method for preparing ammonium nitrate sulfate according to claim 1, wherein: the stirring time in the step 1) is 30-120 minutes.
4. The method for preparing ammonium nitrate sulfate according to claim 1, wherein: the water content of the finished ammonium sulfate nitrate dried in the step 3) is less than or equal to 2 percent.
5. The method for preparing ammonium nitrate according to any one of claims 1 to 4, wherein: the device adopted by the preparation method comprises a nitric acid storage tank (1), wherein the nitric acid storage tank (1) is sequentially communicated with a tubular reactor (2), a flash separator (3), a stirring mixing tank (4), a flash tank (5), a primary evaporator (6), a secondary evaporator (7) and a high tower melting granulation device (9) through pipelines, and the nitric acid storage tank (1) is further sequentially communicated with a neutralization washing tower (8) and the stirring mixing tank (4) through pipelines.
6. The method for preparing ammonium nitrate sulfate according to claim 5, which is characterized in that: tubular reactor (2) are equipped with gaseous ammonia and let in pipe (21), nitric acid and let in pipe (22) and sulphuric acid and let in pipe (23), stirring mixing tank (4) are equipped with ammonium sulfate crystal discharge opening (41) and diammonium hydrogen phosphate discharge opening (42).
7. The method for preparing ammonium nitrate sulfate according to claim 5, which is characterized in that: flash separator (3) are through pipeline and neutralization scrubbing tower (8) intercommunication, second grade evaporimeter (7) are equipped with middling pressure steam and let in pipe (71), stirring mixing tank (4) are through pipeline and flash drum (5), one-level evaporimeter (6) and second grade evaporimeter (7) and communicate in proper order through the pipeline, neutralization scrubbing tower (8) are through pipeline and one-level evaporimeter (6) formation return circuit.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2795495A (en) * | 1953-10-24 | 1957-06-11 | Rubrchemie Ag | Non-caking ammonium sulfate nitrate |
| US6689181B2 (en) * | 2000-11-15 | 2004-02-10 | Honeywell International Inc. | Ammonium sulfate nitrate |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7985393B2 (en) * | 2009-03-31 | 2011-07-26 | Uop Llc | Pastillation of ammonium sulfate nitrate |
| US9932277B2 (en) * | 2010-11-02 | 2018-04-03 | Advansix Resins & Chemicals Llc | Method for producing ammonium sulfate nitrate |
| CN102603387B (en) * | 2012-03-19 | 2013-11-27 | 深圳市芭田生态工程股份有限公司 | Method for producing compound fertilizer by high tower tubular reactor |
| CN104926374B (en) * | 2015-06-30 | 2017-12-19 | 河北冀衡赛瑞化工有限公司 | A kind of production method of sulfenyl nitrate fertilizer |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2795495A (en) * | 1953-10-24 | 1957-06-11 | Rubrchemie Ag | Non-caking ammonium sulfate nitrate |
| US6689181B2 (en) * | 2000-11-15 | 2004-02-10 | Honeywell International Inc. | Ammonium sulfate nitrate |
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