CN108033862B - Preparation method of novel high-strength round granular potassium sulfate - Google Patents
Preparation method of novel high-strength round granular potassium sulfate Download PDFInfo
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- CN108033862B CN108033862B CN201810008341.1A CN201810008341A CN108033862B CN 108033862 B CN108033862 B CN 108033862B CN 201810008341 A CN201810008341 A CN 201810008341A CN 108033862 B CN108033862 B CN 108033862B
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05D—INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
- C05D1/00—Fertilisers containing potassium
- C05D1/02—Manufacture from potassium chloride or sulfate or double or mixed salts thereof
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05D—INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
- C05D3/00—Calcareous fertilisers
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05D—INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
- C05D3/00—Calcareous fertilisers
- C05D3/02—Calcareous fertilisers from limestone, calcium carbonate, calcium hydrate, slaked lime, calcium oxide, waste calcium products
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05D—INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
- C05D5/00—Fertilisers containing magnesium
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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
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
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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
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/70—Mixtures of one or more fertilisers with additives not having a specially fertilising activity for affecting wettability, e.g. drying agents
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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
- C05G5/00—Fertilisers characterised by their form
- C05G5/10—Solid or semi-solid fertilisers, e.g. powders
- C05G5/12—Granules or flakes
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
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- Pest Control & Pesticides (AREA)
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- Fertilizers (AREA)
Abstract
The invention discloses a preparation method of novel high-strength round granular potassium sulfate, which adopts agricultural potassium sulfate powder without crushing, and the method comprises the steps of uniformly mixing granulation auxiliary agents accounting for 2-5% of the total material amount, feeding the mixture into agglomeration granulation equipment, spraying a proper amount of acidity for regulation and granulation, drying, cooling and screening to obtain round granular potassium sulfate with the granularity of 2-4mm, wherein the average strength is 28-45N, the grain strength is enhanced along with the prolonging of the standing time, the nutrient content is high, the K2O content is 48.4-50%, the production process is simple and convenient, the yield is high, the calcium oxide, the magnesium oxide and the calcium sulfate hemihydrate selected in the invention play a role in binding granulation, and can also provide medium elements required by plants.
Description
Technical Field
The invention belongs to the field of fertilizers, and particularly relates to a preparation method of novel high-strength round granular potassium sulfate.
Background
With the rapid development of mechanized fertilization, granulated fertilizers have become the mainstream varieties in the market in the recent years. Potassium sulfate is used as a high-nutrient elemental potassium fertilizer, and is one of indispensable fertilizer varieties of crops (particularly chlorine-avoiding crops such as vegetables, fruit trees, tea, tobacco and the like); therefore, a high-strength high-nutrient granular round potassium sulfate fertilizer becomes a fertilizer urgently needed in the market. Most potassium sulfate products in the market are powdery, but the powdery products are inconvenient to store and transport and fertilize, and are easy to run off and unbalanced in soil nutrients when meeting rainwater or irrigation water; because the potassium sulfate belongs to sand mold materials, the viscosity and plasticity are poor, and the conventional granulation method is difficult.
The production process of granular potassium sulfate commonly used in the market at present mainly comprises three processes; crystallization, extrusion and agglomeration; the crystallization method has the advantages of complex process, high cost, large consumption, irregular particles and low market competitiveness; the product produced by the extrusion method has irregular particles, flaky or polygonal particles and poor roundness, and is easy to have layering phenomenon when being used as a blended fertilizer, thereby causing uneven fertilization. The granular potassium sulfate produced by the existing agglomeration method is usually added with more than 20 percent of binder and filler in the granulation process, which can cause the nutrient of the granular potassium sulfate to be reduced and increase the production cost, and the raw material of the granular potassium sulfate used as the blended fertilizer is often limited by the nutrient proportion.
Granular fertilizers have many advantages over powdered fertilizers: 1. the fertilizer is convenient to apply, can be applied mechanically, is convenient and easy to spread 2. the physical property is good, the granulated fertilizer is free from dust when loading and unloading the vehicle, the fluidity is good, and the granulated fertilizer is not caked after being stored for a long time 3. the fertilizer also can play a role of slow release and improve the utilization rate of the fertilizer. 4. Can be used as elemental potassium fertilizer to be mixed to produce low-cost BB fertilizer. The compound fertilizer has the advantages of simple production process, flexible formula, high efficiency, environmental protection and wide adaptability, and about 60 percent of the fertilizer in North America is applied as the compound fertilizer. The blended fertilizer requires that the particle sizes of all components are basically consistent, otherwise, the layered segregation phenomenon can be generated in the transportation, storage or fertilization process, and the nutrients are not uniform. In view of the development trend of the blended fertilizer, the demand of the round granular potassium sulfate with high strength and high nutrient is relatively short. At present, most of the existing granular potassium sulfate particles in China have the defects of non-uniform particles, low strength, low nutrient content and small yield, and can not meet the requirement of granular potassium fertilizer. Therefore, the selection of proper binding materials, low cost and high performance, and the production of the round granular potassium sulfate with high nutrient content and high product strength without adding or adding less fillers is a problem which needs to be solved urgently in the fertilizer industry.
Disclosure of Invention
The invention provides a preparation method for producing novel high-strength round granular potassium sulfate, which has high nutrient content, high product strength and round appearance, the process is simple to operate, and the problems in the prior art are solved.
The technical scheme adopted by the invention is as follows:
the raw material components required by the high-strength and high-nutrient circular particles comprise: the composite material comprises, by mass, 95-98% of powdered potassium sulfate, 1.6-4% of a bonding auxiliary agent, 0.1-0.2% of a wetting agent and 0.3-0.8% of an acidity regulator; the components are fully mixed, and then granulation can be carried out.
The powder potassium sulfate is agricultural grade powder potassium sulfate, meets the standard of GB20406-2006 agricultural potassium sulfate superior products, and has the potassium oxide nutrient content of 51%.
The bonding auxiliary agent is a mixture of calcium oxide, magnesium oxide and calcium sulfate hemihydrate.
The wetting agent is one or more of polyethylene glycol 400, polyethylene glycol 200 and ferrous sulfate.
The acidity regulator is 98% concentrated sulfuric acid.
The preparation method of the novel high-nutrient high-strength round granular potassium sulfate comprises the following steps:
(1) weighing the potassium sulfate powder in proportion without crushing;
(2) weighing the binder, wherein the weight portion is 1: 1: 3 weighing calcium oxide, magnesium oxide and calcium sulfate hemihydrate, and mixing uniformly;
(3) adding the binder obtained in the step (2) into the potassium sulfate obtained in the step (1), stirring for 5-10min at the speed of 200-400r/min, and uniformly mixing to obtain a material A;
(4) adding the acidity regulator concentrated sulfuric acid into a certain amount of water to prepare dilute acid solution with the mass concentration of 3-8%;
(5) adding the wetting agent into the step (4), and uniformly mixing to obtain a granulation auxiliary agent B;
(6) and (4) pouring the material A obtained in the step (3) into a disc granulator or a rotary drum granulator, starting the granulator, and continuously spraying a granulation auxiliary agent B on the granulated material A by using an atomizing nozzle for agglomeration granulation.
(7) And (3) sequentially feeding the manufactured potassium sulfate particles into a drying, screening and cooling system, packaging the qualified particles, and feeding the crushed unqualified particles into a granulation system as a return material.
Compared with the existing granular potassium sulfate granulation process, the invention has the following advantages: 1. the appearance of the particles is round and round, the particle size is uniform and is 2-4mm, the physical property and the flow property are good, and the particles can be directly used as raw materials of the blended fertilizer; 2. the granule has high strength, the average strength is 35-45N, the stability is good, and the pulverization is not easy; 3. the granular potassium sulfate contains a certain amount of secondary elements, can improve calcium and magnesium elements required by plants, and improves the fertilizer efficiency; 4. the production process is simple and convenient, is suitable for various granulation modes, and adopts the traditional compound fertilizer granulation process, such as a disc granulator or a roller granulator; 5. the conventional agricultural potassium sulfate is adopted to carry out granulation without crushing, the production cost is low, the energy consumption is low, the popularization is easy, the yield is higher than that of extrusion granulation, and the method is suitable for industrial production.
Detailed Description
Example 1
The embodiment provides a potassium sulfate granulation process, which comprises the following raw material components:
weighing 950g of agricultural potassium sulfate without crushing;
according to the binder proportion of 1: 1: 3 weighing 8g of calcium oxide, 8g of magnesium oxide and 24g of calcium sulfate hemihydrate respectively;
weighing 2g of wetting agent polyethylene glycol 200;
weighing 8g of 98% concentrated sulfuric acid, and dissolving in 90ml of water to prepare 8.0% diluted acid solution;
next, the specific granulation step of the granular potassium sulfate comprises:
(1) adding the weighed binder into the weighed agricultural potassium sulfate, putting the mixture into a mixer, stirring for 5-10min at the speed of 200 plus 400r/min, and uniformly mixing to obtain a material A;
(2) adding a wetting agent polyethylene glycol 200 into an 8.0% diluted acid solution, and uniformly mixing to obtain a granulation auxiliary agent B;
(3) and pouring the material A into a disc granulator, starting the granulator, and continuously spraying the granulation auxiliary agent B on the granulated material A by using an atomizing nozzle for agglomeration granulation.
(4) After granulation is finished, putting all the materials into an oven, drying for 2h at 70 ℃, cooling and then sieving for 2-4mm to obtain round granular potassium sulfate, wherein the granulation rate of the potassium sulfate is 91 percent, the yield of 2-4mm granules is 69 percent and the granule strength is 45N.
Example 2
The embodiment provides a potassium sulfate granulation process, which comprises the following raw material components:
980g of agricultural potassium sulfate is weighed without being crushed;
according to the binder proportion of 1: 1: 3, respectively weighing 3g of calcium oxide, 3g of magnesium oxide and 9g of calcium sulfate hemihydrate;
weighing 2g of wetting agent polyethylene glycol 400;
weighing 3g of 98% concentrated sulfuric acid, and dissolving in 90ml of water to prepare a 3.2% dilute acid solution;
next, the specific granulation step of the granular potassium sulfate comprises:
(1) adding the weighed binder into the weighed agricultural potassium sulfate, putting the mixture into a mixer, stirring for 5-10min at the speed of 200 plus 400r/min, and uniformly mixing to obtain a material A;
(2) adding a wetting agent polyethylene glycol 400 into a 3.2% diluted acid solution, and uniformly mixing to obtain a granulation auxiliary agent B;
(3) and pouring the material A into a disc granulator, starting the granulator, and continuously spraying the granulation auxiliary agent B on the granulated material A by using an atomizing nozzle for agglomeration granulation.
(4) After granulation is finished, putting all the materials into an oven, drying for 2h at 70 ℃, cooling, and then sieving for 2-4mm to obtain round granular potassium sulfate, wherein the granulation rate of the potassium sulfate is 90%, the yield of 2-4mm granules is 75%, and the granule strength is 28N.
Example 3
970kg of agricultural potassium sulfate is weighed without being crushed;
according to the binder proportion of 1: 1: 3 weighing 5kg of calcium oxide, 5kg of magnesium oxide and 15kg of calcium sulfate hemihydrate respectively;
weighing 1kg of wetting agent polyethylene glycol 200;
weighing 4kg of 98% concentrated sulfuric acid, dissolving in 90L of water, and preparing a dilute acid solution with the mass concentration of 4.2%;
next, the specific granulation step of the granular potassium sulfate comprises:
(1) adding the weighed binder into the weighed agricultural potassium sulfate, putting the mixture into a mixer, stirring for 5-10min at the speed of 200 plus 400r/min, and uniformly mixing to obtain a material A;
(2) adding a wetting agent polyethylene glycol 200 into a 4.2% diluted acid solution, and uniformly mixing to obtain a granulation auxiliary agent B;
(3) continuously conveying the material A into a rotary drum granulator, starting the granulator, continuously spraying a granulation auxiliary agent B on the granulated material A by using an atomizing nozzle, carrying out agglomeration granulation, and then passing through a drying system and a screening system to obtain round granular potassium sulfate, wherein the granulation rate of the potassium sulfate is 95%, the yield of 2-4mm granules is 78%, the granule strength is 36N, and the granule strength is 40N after the process is placed for 100 days.
Example 4
Weighing 960kg of agricultural potassium sulfate without crushing;
according to the binder proportion of 1: 1: 3 weighing 6kg of calcium oxide, 6kg of magnesium oxide and 18kg of calcium sulfate hemihydrate respectively;
weighing 2kg of wetting agent polyethylene glycol 200;
weighing 8kg of 98% concentrated sulfuric acid, dissolving in 90L of water, and preparing dilute acid solution with the mass concentration of 8.0%;
next, the specific granulation step of the granular potassium sulfate comprises:
(1) adding the weighed binder into the weighed agricultural potassium sulfate, putting the mixture into a mixer, stirring for 5-10min at the speed of 200 plus 400r/min, and uniformly mixing to obtain a material A;
(2) adding a wetting agent polyethylene glycol 200 into an 8.0% diluted acid solution, and uniformly mixing to obtain a granulation auxiliary agent B;
(3) continuously conveying the material A into a rotary drum granulator, starting the granulator, continuously spraying a granulation auxiliary agent B on the granulated material A by using an atomizing nozzle, carrying out agglomeration granulation, and then passing through a drying system and a screening system to obtain round granular potassium sulfate, wherein the granulation rate of the potassium sulfate is 95%, the yield of 2-4mm granules is 78%, the granule strength is 37N, and the granule strength is 45N after the process is placed for 100 days.
Experimental example 1
The potassium sulfate granules prepared in examples 1 to 4 were subjected to index analysis and measurement, and the results are shown in table 1 below.
TABLE 1 Potassium sulfate granule index analysis
| Numbering | K2O content (%) | Content of Medium element (%) | Yield (2-4 mm) | Average intensity (N) | Water content (%) | Results |
| 1 | 48 | 1.2 | 79 | 45 | 0.8 | Qualified |
| 2 | 49.9 | 0.5 | 75 | 35 | 0.6 | Qualified |
| 3 | 49.2 | 0.7 | 78 | 33 | 1.0 | Qualified |
| 4 | 48.9 | 1.1 | 81 | 37 | 1.0 | Qualified |
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (4)
1. The preparation method of the high-strength round granular potassium sulfate is characterized by comprising the following steps of: adding a granulation auxiliary agent accounting for 2-5% of the total material amount into agricultural potassium sulfate powder serving as a raw material, uniformly mixing, feeding into agglomeration granulation equipment, spraying a proper amount of acidity regulator for granulation, drying, cooling and screening to obtain round high-strength uniform potassium sulfate particles;
the granulation auxiliary agent comprises a binder and a wetting agent;
the binder is a mixture of magnesium oxide, calcium oxide and calcium sulfate hemihydrate, and the addition amount of the binder is 1.6-4.0% by mass percent of the components; the mass ratio of the components of the magnesium oxide, the calcium oxide and the calcium sulfate hemihydrate is 1: 1: 3;
the acidity regulator is concentrated sulfuric acid, and the addition amount of the acidity regulator is 0.3% -0.8%;
the agricultural potassium sulfate powder does not need to be crushed, and the addition amount is 95-98% by mass percent;
the addition amount of the wetting agent in the granulation auxiliary agent is 0.1-0.2%.
2. The method for preparing high-strength round granular potassium sulfate as claimed in claim 1, wherein the wetting agent in the granulation auxiliary agent is one or more of polyethylene glycol 400, polyethylene glycol 200 and ferrous sulfate.
3. The method for preparing high-strength round granular potassium sulfate according to claim 1, wherein the acidity regulator concentrated sulfuric acid is required to be prepared into a dilute acid solution, and the required water amount is 9% of the total material amount by mass percent.
4. The method for preparing the high-strength round granular potassium sulfate as claimed in claim 1, wherein the grain size of the potassium sulfate grains is 2-4mm, the average strength is 28-45N, and K is2The content of O is 48.4-50%.
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| CN109704863A (en) * | 2019-02-18 | 2019-05-03 | 湖北三宁化工股份有限公司 | A kind of bulky grain sulfur-containing nitrogen fertilizer and preparation method thereof |
| CN109851429A (en) * | 2019-02-25 | 2019-06-07 | 齐齐哈尔大学 | A kind of preparation method that powder fertilizer can be made to spheric granules of extrusion granulating method |
| AU2020202788A1 (en) * | 2020-04-27 | 2021-11-11 | Pact Renewables Pty Ltd | Mineral-based composites |
| GB2611904A (en) * | 2020-06-25 | 2023-04-19 | Pact Renewables Pty Ltd | Degradable materials containing waste paper products |
| CN112919933A (en) * | 2021-04-13 | 2021-06-08 | 康伟华 | Method for preparing organic potassium sulfate round granular fertilizer |
| CN113149793A (en) * | 2021-04-23 | 2021-07-23 | 湖北富邦科技股份有限公司 | Neutral round particle potassium sulfate fertilizer and manufacturing method thereof |
| CN113105292A (en) * | 2021-04-23 | 2021-07-13 | 湖北富邦科技股份有限公司 | Production method of synergistic potash fertilizer capable of improving yield |
| CN113603558A (en) * | 2021-07-20 | 2021-11-05 | 烟台市烟农富邦肥料科技有限公司 | Granulation method for increasing wet strength of round granular potash fertilizer |
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| CN1187116C (en) * | 2000-11-30 | 2005-02-02 | 南化集团研究院 | Process for preparing granular fertilizer |
| CN1218908C (en) * | 2003-03-10 | 2005-09-14 | 铜陵化学工业集团有限公司 | Potassium chloride united pelleting process |
| CN103819271B (en) * | 2014-02-25 | 2016-04-27 | 湖北富邦科技股份有限公司 | A kind of manufacture method of novel particle Repone K fertilizer |
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