CN1280111A - Middle concentrate compound potassium sulfate fertilizer and its producing method - Google Patents
Middle concentrate compound potassium sulfate fertilizer and its producing method Download PDFInfo
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- CN1280111A CN1280111A CN 99112315 CN99112315A CN1280111A CN 1280111 A CN1280111 A CN 1280111A CN 99112315 CN99112315 CN 99112315 CN 99112315 A CN99112315 A CN 99112315A CN 1280111 A CN1280111 A CN 1280111A
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G1/00—Mixtures of fertilisers belonging individually to different subclasses of C05
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Abstract
The present invention relates to a compound chemical fertilizer and its production technology. The compound fertilizer has a total azophoska content of 25-35 % and is produced through the reaction of excessive concentrated sulfuric acid and KCI to produce KHSO4, further reaction with phosphate rock powder pulp, neutralization with ammonia, pulp spraying and pelletizing. The compound fertilizer contains also trace elements beneficial to improving soil. The production process of the present invention has low production cost, no sludge producing phosphoric acid production process, and reduced environmental pollution.
Description
A medium-concentration potassium sulfate compound fertilizer and a production method thereof belong to the technical field of chemical fertilizers and production thereof, and relate to a compound fertilizer produced by using sulfuric acid, potassium chloride, ground phosphate rock and liquid ammonia and a production method thereof.
The existing potassium sulfate compound fertilizer is a high-concentrationcompound fertilizer, wherein the contents of nitrogen, phosphorus and potassium are all 15%, and the demand on nitrogen and phosphorus is low because the contents of nitrogen and phosphorus in domestic soil are high, so that the high-concentration compound fertilizer has high nitrogen and phosphorus concentrations for the current soil conditions. Some medium-concentration compound fertilizers are prepared by mixing high-concentration compound fertilizers with filling materials, and the medium-concentration potassium sulfate compound fertilizers are not produced, used or reported.
A process for preparing high-concentration potassium sulfate compound fertilizer includes such steps as reaction of sulfuric acid on potassium chloride to obtain potassium bisulfate slurry, reaction of potassium bisulfate on phosphoric acid, introducing ammonia gas for neutralization, concentrating the neutralized slurry, spraying slurry, granulating and drying. For example, the patent No. 97105751 granted by the Chinese patent office discloses a production method of sulfur-based NPK compound fertilizer, which uses concentrated sulfuric acid and potassium chloride to produce potassium bisulfate, then adds diluted phosphoric acid, uses ammonia to neutralize, then adds urea, and makes them pass through such processes of spraying, granulating and drying so as to obtain the invented sulfur-based potassium sulfate compound fertilizer whose nitrogen, phosphorus and potassium contents are respectively 15%. The phosphoric acid used by the production method is prepared from phosphorite and is further used for producing compound fertilizer, the cost is high, and a large amount of waste phosphogypsum (calcium sulfate) is generated in the process of preparing the phosphoric acid, so that waste is caused.
The invention aims to provide a medium-concentration potassium sulfate compound fertilizer suitable for the current soilmoisture content and a production method of the medium-concentration potassium sulfate compound fertilizer so as to overcome the defects of the prior art.
The medium-concentration potassium sulfate compound fertilizer consists of the following components: NH (NH)4H2PO47-11％ (NH4)SO4·CaSO4·H2O 26-34％K2SO4·CaSO4·H2O 32-40％ Ca(H2PO4)21-4％CaHPO41-4％ NH4Cl 2-5％ NH4Cl·CO(NH2)23-8％(Fe．Al)(NH4)2H2F(PO4)22-5％And the balance: 5 to 10 percent. Wherein nitrogen (N) and phosphorus (P)2O5) Potassium (K)2O) is 6-10%, 5-9% and 13-17%, total N, P, K content is 25-35%, and the rest is metal salt such as Fe, Al, Mg, Zn and Na.
The product of the invention is prepared by preparing potassium bisulfate from concentrated sulfuric acid and potassium chloride, then directly reacting with ground phosphate rock, then introducing ammonia gas for neutralization to prepare slurry, adding urea into the slurry, and then spraying, granulating and drying.
The potassium sulfate compound fertilizer of the present inventionThe production method of (a) is such that: 1. using concentrated sulfuric acid (92-98%) and potassium chloride (solid, K)255-62% by weight of O) to prepare potassium bisulfate slurry, and recovering HCL. During reaction, concentrated sulfuric acid is heated to 70-120 ℃, potassium chloride is put into the concentrated sulfuric acid, and the molar ratio of the concentrated sulfuric acid to the potassium chloride is 1.1-1.5: l. The reaction is as follows: the reaction time is 60-120 minutes, and the reaction temperature is 70-120 ℃.
2. The potassium bisulfate slurry containing excessive sulfuric acid and the phosphate rock powder (the main component is Ca)5F(PO4)3]Slurry reaction, the ground phosphate rock is particles ground from phosphate rock, the phosphate rock powder is made into slurry by adding water, its liquid-solid ratio (by weight) is 0.8-1.0]Preparing mixed slurry, and recovering HF, wherein the reaction temperature is 70-90 ℃ and the reaction time is 60-90 minutes. The weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.2-3.4.
3. The mixture slurry prepared above was neutralized to weak acidity (PH 5-6.8) with gaseous ammonia.
4. Spraying, granulating and drying the slurry by a conventional method to obtain the medium-concentration potassium sulfate compound fertilizer, wherein N, P (P) is used as the potassium sulfate compound fertilizer2O5)、K(K2O) is 6-10%, 5-9% and 13-17% respectively.
If the product has a low N content, urea (N46%) may be added to the slurry.
Because the grades of the ground phosphate rock are different in different regions, in the production process, the grade of the ground phosphate rock is firstly tested, and the production formula is calculated according to the product2O5The medium-concentration potassium sulfate compound fertilizer is produced by taking 30 percent of powdered rock phosphate as a standard calculation.
The products of the invention and the process for their production are described in detail below
The medium-concentration potassium sulfate compound fertilizer has total N content of 7-9% and total phosphorus (P)2O5) 6-8% of total potassium(K)2O) content of 14-16%, and the phases are as follows: NH (NH)4H2PO48-10％(NH4)SO4·CaSO4·H2O 28-32％K2SO4·CaSO4·H2O 35-37％ Ca(H2PO4)22-3％CaHPO42-3％ NH4Cl 3-5％ NH4Cl·CO(NH2)25-6％(Fe．Al)(NH4)2H2F(PO4)23-4% of the balance: 6 to 9 percent.
The production method of the potassium sulfate compound fertilizer with the content comprises the following steps: 1. using concentrated sulfuric acid (98%) and potassium chloride (solid, K)2The O content is 6O% by weight) is reacted in a reaction kettle to prepare potassium bisulfate slurry, and HCL is recovered. During reaction, concentrated sulfuric acid is heated to 70-80 ℃, potassium chloride is put into the concentrated sulfuric acid, and the molar ratio of the concentrated sulfuric acid to the potassium chloride is 1.1-1.2: 1. The reaction is as follows: h2SO4(excess) + KCl = KHSO4The + HCl ↓timeis 60 to 90 minutes.
2. Excessive potassium bisulfate slurry prepared in the above way and phosphate rock powder (the main component is Ca)5F(PO4)3]The slurry enters a reaction tank to react to prepare mixed slurry, the liquid-solid ratio of the ground phosphate rock slurry is 0.89-0.92, the weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.5-2.8, HF is recovered, and the mixed slurry is emptied after washing.
3. And (3) feeding the prepared mixed slurry into a mixed acid storage tank, pumping the mixed slurry into a tubular reactor by a pump, introducing ammonia gas, and neutralizing to weak acidity to obtain the slurry with the pH value of 5-6.8.
4. The weakly acidic slurry is put into a slurry spraying groove, and urea (the nitrogen content is 46 percent) is added in an amount of 0.02 to 0.03 ton per cubic slurry.
5. Spraying the slurry, granulating, drying, sieving, cooling, and packaging to obtain medium-concentration potassium sulfate compound fertilizer containing N, P (P)2O5)、K(K2O) content of 7-9%, 6-8% and 14-16%, and total N, P, K content of 25-35%.
Example 1
The medium-concentration potassium sulfate of the present inventionThe total N content of the compound fertilizer is 8 percent, and the total phosphorus (P)2O5) Content 7%, total potassium (K)2O) content 15%, and its phase composition is as follows:NH4H2PO49．0％(NH4)SO4CaSO4H2O 30．0％K2SO4·CaSO4·H2O 36．0％ Ca(H2PO4)22．5％CaHPO42．0％ NH4Cl 3．0％ NH4Cl·CO(NH2)25．5％(Fe．Al)(NH4)2H2F(PO4)23.0% balance: 9.0 percent.
The production method of the potassium sulfate compound fertilizer with the content comprises the following steps: 1. using concentrated sulfuric acid (98%) and potassium chloride (solid, K)2The O content is 60 percent by weight) is reacted in a reaction kettle to prepare potassium bisulfate slurry, and HCL is recovered. During reaction, concentrated sulfuric acid is heated to 80 ℃, potassium chloride is put into the concentrated sulfuric acid, and the molar ratio of the concentrated sulfuric acid to the potassium chloride is 1.1: 1. The reaction is as follows: the reaction time was 90 minutes.
2. The potassium bisulfate slurry containing excessive sulfuric acid and the phosphate rock powder (the main component is Ca)5F(PO4)3]And (3) allowing the slurry to enter a reaction tank for reaction to prepare mixed slurry, wherein the liquid-solid ratio of the ground phosphate rock slurry is 0.90, and the weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.8, recovering HF, washing and emptying.
3. And (3) feeding the prepared mixed slurry into a mixed acid storage tank, pumping the mixed slurry into a tubular reactor by a pump, introducing ammonia gas, and neutralizing to weak acidity to obtain slurry with the pH value of 6.
4. Weakly acidic slurry is put into a slurry spraying groove, and urea (the nitrogen content is 46 percent) is added in an amount of 0.02 ton per cubic slurry.
5. Spraying the slurry, granulating, drying, sieving, cooling, and packaging to obtain medium-concentration potassium sulfate compound fertilizer containing N, P (P)2O5)、K(K2O) content of 8 percent and 7 percent respectively,15％。
Example 2
The medium-concentration potassium sulfate compound fertilizer has the total N content of 9 percent and the total phosphorus (P)2O5) Content 6%, total potassium (K)2O) content 14%, the phase composition is as follows: NH (NH)4H2PO48．5％(NH4)SO)4·CaSO4·H2O 30．5％K2SO4·CaSO4·H2O 35．0％ Ca(H2PO4)22．4％CaHPO42．0％ NH4Cl 3．5％ NH4Cl·CO(NH2)25．8％(Fe．Al)(NH4)2H2F(PO4)23.1% balance: 9.2 percent.
The production method of the potassium sulfate compound fertilizer with the content comprises the following steps: 1. using concentrated sulfuric acid (98%) and potassium chloride (solid, K)2The O content is 60 percent by weight) is reacted in a reaction kettle to prepare potassium bisulfate slurry, and HCL is recovered. During reaction, concentrated sulfuric acid is heated to 80 ℃, potassium chloride is put into the concentrated sulfuric acid, and the molar ratio of the concentrated sulfuric acid to the potassium chloride is 1.2: 1. The reaction is as follows: the reaction time was 90 minutes.
2. The potassium bisulfate slurry containing excessive sulfuric acid and the phosphate rock powder (the main component is Ca)5F(PO4)3]And (3) allowing the slurry to enter a reaction tank for reaction to prepare mixed slurry, wherein the liquid-solid ratio of the ground phosphate rock slurry is 0.90, and the weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.7, recovering HF, washing and emptying.
3. And (3) feeding the prepared mixed slurry into a mixed acid storage tank, pumping the mixed slurry into a tubular reactor by a pump, introducing ammonia gas, and neutralizing to weak acidity to obtain slurry with the pH value of 6.
4. Weakly acidic slurry is put into a slurry spraying groove, and urea (the nitrogen content is 46 percent) is added, wherein the adding amount is 0.025 ton per cubic slurry.
5. The slurry is prepared by spraying, granulating, drying, screening, cooling and packaging the slurry by a conventional methodObtaining medium-concentration potassium sulfate compound fertilizer, wherein N, P (P)2O5)、K(K2O) contents of 9%, 6% and 14%, respectively.
Example 3
The medium-concentration potassium sulfate compound fertilizer has the total N content of 8 percent and the total phosphorus (P)2O5) Content 9%, total potassium (K)2O) content 15%, and its phase composition is as follows: NH (NH)4H2PO49．5％ (NH4)SO4·CaSO4·H2O 30．0％K2SO4·CaSO4·H2O 36．0％ Ca(H2PO4)23．0％CaHPO42．5％ NH4Cl 3．0％ NH4Cl·CO(NH2)25．5％(Fe．Al)(NH4)2H2F(PO4)23.5% balance: 7.0 percent.
The production method of the potassium sulfate compound fertilizer with the content comprises the following steps: 1. with concentrated sulphuric acid(98%) with potassium chloride (solid, K)2The O content is 60 percent by weight) is reacted in a reaction kettle to prepare potassium bisulfate slurry, and HCL is recovered. During reaction, concentrated sulfuric acid is heated to 80 ℃, potassium chloride is put into the concentrated sulfuric acid, and the molar ratio of the concentrated sulfuric acid to the potassium chloride is 1.12: 1. The reaction is as follows: the reaction time was 90 minutes.
2. The potassium bisulfate slurry containing excessive sulfuric acid and the phosphate rock powder (the main component is Ca)5F(PO4)3]And (3) reacting the slurry in a reaction tank to obtain mixed slurry, wherein the liquid-solid ratio of the ground phosphate rock slurry is 0.90, and the weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.65, recovering HF, washing and emptying.
3. And feeding the prepared mixed slurry into a mixed acid storage tank, pumping the mixed slurry into a tubular reactor by a pump, introducing ammonia gas, and neutralizing to weak acidity to obtain the slurry with the pH value of 6.
4. Weakly acidic slurry is put into a slurry spraying groove, and urea (the nitrogen content is 46 percent) is added in an amount of 0.02 ton per cubic slurry.
5. Spraying the slurry, granulating, drying, sieving, cooling, and packaging to obtain medium-concentration potassium sulfate compound fertilizer containing N, P (P)2O5)、K(K2O) contents of 8%, 9% and 15%, respectively.
The medium-concentration potassium sulfate compound fertilizer has low nitrogen and phosphorus content and high potassium content, is suitable for the soil moisture content of the existing soil, and simultaneously has trace elements in the phosphate rock powder which are beneficial to the soil.
Claims (8)
1. The medium-concentration potassium sulfate compound fertilizer is prepared by compounding KCL, sulfuric acid, ground phosphate rock and ammonia, and is characterized in that: n, P, K is 6-10%, 5-9% and 13-17%, the total N, P, K content is 25-35%, and the phases are as follows: NH (NH)4H2PO47-11％(NH4)SO4·CaSO4·H2O 26-34％K2SO4·CaSO4·H2O 32-40％ Ca(H2PO4)21-4％CaHPO41-4％ NH4Cl 3-5％ NH4Cl·CO(NH2)23-8％(Fe．Al)(NH4)2H2F(PO4)22-5% of the balance: 5 to 10 percent.
2. The method for producing the medium-concentration potassium sulfate compound fertilizer as claimed in claim 1 comprises the following steps: 1) using concentrated sulfuric acid (92-98%) and potassium chloride (solid, K)255-62% by weight of O) to prepare potassium bisulfate slurry, and recovering HCL. During reaction, concentrated sulfuric acid is heated to 70-120 ℃, potassium chloride is put into the concentrated sulfuric acid, and the molar ratio of the concentrated sulfuric acid to the potassium chloride is 1.1-1.5: 1. The reaction is as follows: the reaction time is 60-120 minutes, and the reaction temperature is70-120 ℃.
2) Potassium bisulfate slurry containing excessive sulfuric acid prepared by the method and phosphate rock powder (the main component is Ca)5F(PO4)3]Reacting the slurry to prepare mixed slurry, recovering HF, wherein the liquid-solid ratio (by weight) of the ground phosphate rock slurry is 0.8-1.0, the reaction temperature is 70-90 ℃, and the reaction time is 60-90 minutes. The weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.2-3.4.
3) And neutralizing the mixture slurry prepared by the method to weak acidity (pH value of 5-6.8) by using gas ammonia.
4) Spraying, granulating and drying the slurry by a conventional method to obtain the medium-concentration potassium sulfate compound fertilizer, wherein N, P (P) is used as the potassium sulfate compound fertilizer2O5)、K(K2O) is 6-10%, 5-9% and 13-17% respectively.
3. The medium-concentration potassium sulfate compound fertilizer as claimed in claim 1, which is characterized in that: total N content of 7-9%, total phosphorus (P)2O5) 6-8% of total potassium (K)2O)Content is 14-16%,and its phase is as follows: NH (NH)4H2PO48-10％(NH4)SO4·CaSO4·H2O 28-32％K2SO4·CaSO4·H2O 35-37％ Ca(H2PO4)22-3％CaHPO42-3％ NH4Cl 3-5％ NH4Cl·CO(NH2)25-6％(Fe．Al)(NH4)2H2F(PO4)23-4% of the balance: 6 to 9 percent.
4. The medium-concentration potassium sulfate compound fertilizer as claimed in claim 3, which is characterized in that: total N content 8%, total phosphorus (P)2O5) Content 7%, total potassium (K)2O) content 15%, and its phase composition is as follows: NH (NH)4H2PO49．0％ (NH4)SO4·CaSO4·H2O 30．0％K2SO4·CaSO4·H2O 36．0％ Ca(H2PO4)22．5％CaHPO42．0％ NH4Cl 3．0％ NH4Cl·CO(NH2)25．5％(Fe．Al)(NH4)2H2F(PO4)23.0% balance: 9.0 percent.
5. The method for producing the medium-concentration potassium sulfate compound fertilizer as claimed in claim 2, which is characterized by comprising the following steps of: adding urea (N content is 46%) into the slurry, and the adding amount is 0.02-0.03 ton/m3And (4) slurry.
6. The method for producing the medium-concentration potassium sulfate compound fertilizer as claimed in claim 2, which is characterized by comprising the following steps of: the molar ratio of concentrated sulfuric acid to KCL is 1.1-1.2: 1.
7. The method for producing the medium-concentration potassium sulfate compound fertilizer as claimed in claim 2, which is characterized by comprising the following steps of: the weight ratio of the potassium bisulfate slurry to the ground phosphate rock is 2.5-2.8.
8. The method for producing the medium-concentration potassium sulfate compound fertilizer as claimed in claim 2, which is characterized by comprising the following steps of: the liquid-solid ratio of the ground phosphate rock slurry is 0.89-0.92.
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| CN 99112315 CN1280111A (en) | 1999-07-13 | 1999-07-13 | Middle concentrate compound potassium sulfate fertilizer and its producing method |
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| CN 99112315 CN1280111A (en) | 1999-07-13 | 1999-07-13 | Middle concentrate compound potassium sulfate fertilizer and its producing method |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102126741A (en) * | 2011-01-20 | 2011-07-20 | 山东金正大生态工程股份有限公司 | Method for producing nitro/S-based compound fertilizer and coproducing plaster |
| CN102126738A (en) * | 2011-01-20 | 2011-07-20 | 山东金正大生态工程股份有限公司 | Method for producing nitrophosphate fertilizer and co-producing gypsum through decomposing phosphorite with nitric acid |
| CN105503367A (en) * | 2015-12-30 | 2016-04-20 | 川恒生态科技有限公司 | Method for producing acid nitrogen phosphorus and potassium water soluble fertilizer by adopting wet process phosphoric acid |
| CN106220278A (en) * | 2016-07-27 | 2016-12-14 | 中化化肥有限公司成都研发中心 | A kind of additive improving potassium sulfate compound fertilizer granule strength and the preparation method of high-strength complex Hefei granule |
| CN106748017A (en) * | 2016-12-02 | 2017-05-31 | 锦西天然气化工有限责任公司 | A kind of production method of urea general calcium composite fertilizer |
-
1999
- 1999-07-13 CN CN 99112315 patent/CN1280111A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102126741A (en) * | 2011-01-20 | 2011-07-20 | 山东金正大生态工程股份有限公司 | Method for producing nitro/S-based compound fertilizer and coproducing plaster |
| CN102126738A (en) * | 2011-01-20 | 2011-07-20 | 山东金正大生态工程股份有限公司 | Method for producing nitrophosphate fertilizer and co-producing gypsum through decomposing phosphorite with nitric acid |
| CN102126741B (en) * | 2011-01-20 | 2012-11-28 | 山东金正大生态工程股份有限公司 | Method for producing nitro/S-based compound fertilizer and coproducing plaster |
| CN102126738B (en) * | 2011-01-20 | 2012-11-28 | 山东金正大生态工程股份有限公司 | Method for producing nitrophosphate fertilizer and co-producing gypsum through decomposing phosphorite with nitric acid |
| CN105503367A (en) * | 2015-12-30 | 2016-04-20 | 川恒生态科技有限公司 | Method for producing acid nitrogen phosphorus and potassium water soluble fertilizer by adopting wet process phosphoric acid |
| CN106220278A (en) * | 2016-07-27 | 2016-12-14 | 中化化肥有限公司成都研发中心 | A kind of additive improving potassium sulfate compound fertilizer granule strength and the preparation method of high-strength complex Hefei granule |
| CN106748017A (en) * | 2016-12-02 | 2017-05-31 | 锦西天然气化工有限责任公司 | A kind of production method of urea general calcium composite fertilizer |
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