阅读说明：本技术 尿素硫酸镁肥及其制备方法 (Urea magnesium sulfate fertilizer and preparation method thereof ) 是由 方进 顾春光 任光耀 黄德明 于 2019-11-21 设计创作，主要内容包括：本发明涉及化肥领域,具体而言,提供了一种尿素硫酸镁肥及其制备方法。本发明提供一种尿素硫酸镁肥的制备方法,将硫酸镁与熔融的尿素合成,经造粒得到尿素硫酸镁肥。发明人研发过程中首次发现,仅以硫酸镁和尿素为原料即可得到含氮硫镁的肥料,该制备方法工艺简单,原料的转化率高。制备得到的尿素硫酸镁肥含适量酰态氮、水溶镁和硫,全水溶,肥效快,与单纯尿素相比,具有氮素利用率高,肥效明显等优点。(The invention relates to the field of chemical fertilizers, and particularly provides urea magnesium sulfate fertilizers and a preparation method thereof.A preparation method of urea magnesium sulfate fertilizers is provided, magnesium sulfate and molten urea are synthesized, and the urea magnesium sulfate fertilizers are obtained through granulation.)

The preparation method of 1, kinds of urea magnesium sulfate fertilizer is characterized by that the urea magnesium sulfate fertilizer is obtained by synthesizing magnesium sulfate and molten urea and granulating.

2. The preparation method according to claim 1, characterized in that, according to the parts by mass, the urea is 55-95 parts, the magnesium sulfate is 5-45 parts, and the total part of the urea and the magnesium sulfate is 100 parts;

preferably, the urea accounts for 60-90 parts, and the magnesium sulfate accounts for 10-40 parts;

preferably, the urea accounts for 70-80 parts, and the magnesium sulfate accounts for 20-30 parts.

3. The preparation method of claim 1, wherein magnesium sulfate is synthesized with molten urea, trace elements are added and mixed uniformly, and the trace element type urea magnesium sulfate fertilizer is obtained through granulation;

preferably, the trace elements are 0-1.5 parts by weight, and the total parts of urea, magnesium sulfate and trace elements is 100 parts by weight.

4. The process according to claim 1, characterized in that the temperature of the molten urea is preferably 125-130 ℃;

preferably, the reaction temperature for the synthesis is 125-130 ℃.

5. The method of claim 1, wherein the reaction time of the synthesis is 0.25 to 0.5 hours.

6. The method of claim 1, wherein the granulation process comprises tower granulation, drum granulation, disc granulation, spray granulation or steel belt granulation.

7. The method as claimed in claim 1, wherein the temperature of the granulation is 100-120 ℃.

8. The method of any one of claims 1-7 and , further comprising the steps of cooling and sieving sequentially after the granulating.

9. The preparation method according to claim 8, wherein the screening is performed to obtain a finished urea magnesium sulfate fertilizer product with the particle size of 2-4 mm.

10. The urea magnesium sulfate fertilizer prepared by the preparation method of any in claims 1-9, wherein the urea magnesium sulfate fertilizer contains N25-43 w/w%, Mg 1-8 w/w% and S1-10 w/w%.

Technical Field

The invention relates to the field of fertilizers, in particular to a urea magnesium sulfate fertilizer and a preparation method thereof.

Background

Nitrogen is an important component of protein, nucleic acid, chlorophyll, plant enzyme vitamin and alkaloid, and is used for promoting division and growth of cells, so that the leaf area of crops is large, the crops are dark green, when the crops are lack of nitrogen, the crops grow slowly, the plants are short and small, the leaves are thin and yellow, gramineous plants are few in tillering, short and small in ears, the seeds are not full, and dicotyledonous plants are few in branches and easy to senilis, so that the nitrogen fertilizer is an essential large element for growth and development of the crops, urea is high-concentration nitrogen fertilizers, belongs to neutral quick-acting fertilizers, and can also be used for producing various compound fertilizers, and the urea does not remain any harmful substances in soil and has no adverse effect after long-term application, so is widely applied, however, the nitrogen fertilizer is easy to enter the atmosphere in a gas form or be washed away by rain before being absorbed by the crops, and.

In addition, sulfur and magnesium are important elements required for crop growth, and often need to be replenished during the growth of the crop. Sulfur can promote nitrogen absorption, has important effect on respiration, and has reduced chlorophyll content and less nodule formation in case of sulfur deficiency. Magnesium is a component of chlorophyll, is also an activator of many enzymes, can promote the conversion and absorption of phosphorus, and can synthesize vitamin A, C and has antagonistic effect on calcium, potassium, ammonium and hydrogen plasmas.

However, the prior art does not address the production of fertilizers from nitrogen, sulfur and magnesium.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

The th purpose of the invention is to provide a preparation method of urea magnesium sulfate fertilizers, so as to relieve the technical problem that urea magnesium sulfate fertilizer preparation processes are lacked in the prior art.

The second purpose of the invention is to provide urea magnesium sulfate fertilizers, so as to relieve the shortage of fertilizers containing nitrogen, sulfur and magnesium simultaneously in the prior art and improve the utilization rate of nitrogen.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

A process for preparing urea-magnesium sulfate fertilizer includes such steps as synthesizing magnesium sulfate with molten urea, and granulating.

, according to the mass parts, 55-95 parts of urea, 5-45 parts of magnesium sulfate and 100 parts of total parts of urea and magnesium sulfate;

preferably, the urea accounts for 60-90 parts, and the magnesium sulfate accounts for 10-40 parts;

preferably, the urea accounts for 70-80 parts, and the magnesium sulfate accounts for 20-30 parts.

, synthesizing magnesium sulfate and molten urea, adding trace elements, mixing, and granulating to obtain trace element type urea magnesium sulfate fertilizer;

preferably, the trace elements are 0-1.5 parts by weight, and the total parts of urea, magnesium sulfate and trace elements is 100 parts by weight.

, the temperature of the molten urea is preferably 125-130 ℃.

Preferably, the reaction temperature for the synthesis is 125-130 ℃.

Further , the reaction time for the synthesis is 0.25 to 0.5 hours.

, the granulating method includes tower granulating, drum granulating, disc granulating, spray granulating or steel belt granulating.

Further , the temperature of the granulation is 100-120 ℃.

, the said process also includes the steps of cooling and sieving successively after pelletizing.

And , screening to obtain the urea magnesium sulfate fertilizer with the particle size of 2-4 mm.

The urea magnesium sulfate fertilizer prepared by the preparation method contains 25-43 w/w% of N, 1-8 w/w% of Mg and 1-10 w/w% of S.

Compared with the prior art, the invention has the beneficial effects that:

the invention provides a preparation method of urea magnesium sulfate fertilizers, which synthesizes magnesium sulfate and fused urea, and obtains the urea magnesium sulfate fertilizers through granulation.A research of an inventor discovers for the first time that fertilizers containing nitrogen, sulfur and magnesium can be obtained only by taking the magnesium sulfate and the urea as raw materials, the preparation method has a simple process and high conversion rate of the raw materials.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a flow chart of a preparation process of a urea magnesium sulfate fertilizer provided by the invention.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer.

Unless otherwise defined, technical and scientific terms used herein have the same meaning as is familiar to those skilled in the art. In addition, any methods or materials similar or equivalent to those described herein can also be used in the present invention.

A process for preparing urea-magnesium sulfate fertilizer includes such steps as synthesizing magnesium sulfate with molten urea, and granulating.

The inventor finds for the first time that the fertilizer containing nitrogen, sulfur and magnesium can be obtained only by taking magnesium sulfate and urea as raw materials, and the preparation method has the advantages of simple process and high conversion rate of the raw materials. In the existing technology for preparing the fertilizer, a high-content magnesium raw material needs to be directly added into a melt for granulation, and the granulator is easy to block in the production process, so that the production cannot be carried out, so that the limitation of the technology is met, and the content of water-soluble magnesium in a final product is generally low. The preparation process flow chart of the urea magnesium sulfate fertilizer is shown in figure 1.

In a preferred embodiment, the urea is 55-95 parts by mass, the magnesium sulfate is 5-45 parts by mass, and the total part of the urea and the magnesium sulfate is 100 parts by mass. The inventor finds that when 55-95 parts of urea is obtained, 5-45 parts of magnesium sulfate is obtained through test debugging and optimization, and the urea magnesium sulfate fertilizer obtained in the proportion range has good fertilizer efficiency. Urea is typically, but not limited to, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, or 95 parts by mass; magnesium sulfate is typically, but not limited to, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, or 45 parts.

In a preferred embodiment, the urea comprises 60-90 parts by mass of urea and 10-40 parts by mass of magnesium sulfate.

In a preferred embodiment, the urea and the magnesium sulfate are 70-80 parts and 20-30 parts by mass.

In a preferred embodiment, magnesium sulfate and molten urea are synthesized, trace elements are added and mixed uniformly, and the trace element type urea magnesium sulfate fertilizer is obtained through granulation. The trace element type urea magnesium sulfate fertilizer can be obtained by adding trace elements in the preparation process, and the types of effective substances of the product are enriched.

In a preferred real-time mode, the trace elements are 0-1.5 parts by weight, and the total parts of urea, magnesium sulfate and trace elements is 100 parts by weight. The trace elements are typically, but not limited to, 0.1 part, 0.5 part, 0.8 part, 1 part, 1.2 parts, or 1.5 parts.

It should be noted that the total parts of the raw materials in the preparation process of the invention are 100 parts by weight.

In a preferred embodiment, the temperature of the molten urea is 125-130 ℃, the reaction temperature of the synthesis is 125-130 ℃, the reaction time of the synthesis is preferably 0.25-0.5 hours, the urea is heated to a molten state at the temperature, the synthesis reaction with magnesium sulfate is facilitated in aspect, biuret is avoided in aspect, the quality of the final product is influenced, the synthesis reaction can generate double salt after the magnesium sulfate is added into the molten urea, the state of the substance is stabilized, the synthesis reaction temperature is typically, but not limited to 125 ℃, 126 ℃, 127 ℃, 128 ℃, 129 ℃ or 130 ℃, and the synthesis reaction time is typically, but not limited to 0.25 hour, 0.35 hour, 0.45 hour or 0.5 hour.

In a preferred embodiment, the granulation process comprises tower granulation, drum granulation, disc granulation, spray granulation or steel belt granulation.

The high tower granulation process technology utilizes the characteristic that urea and magnesium sulfate can form eutectic point compounds, urea and magnesium sulfate react to generate a eutectic body with good fluidity, the eutectic body is sprayed into a granulation tower through a special granulator, and the eutectic body is cooled and solidified in air to form granules, so that the urea magnesium sulfate fertilizer is obtained.

The spray granulation is a process of synthesizing magnesium sulfate and molten urea, and then forming the remaining solid which is not vaporized into granules by heating and pumping.

The drum granulation is that folding shoveling plates are uniformly distributed on the inner wall of a rotating drum, a fixed fluidized bed is arranged in the drum, returned particles are continuously added from a feeding end of the drum, the shoveling plates shovel the particles at the bottom of the drum into the fluidized bed, the particles flow down from an overflow port to form a continuous and uniform material curtain, a plurality of nozzles are arranged on the side surface of the drum, which is vertical to the material curtain in the axial direction, the nozzles atomize slurry synthesized by urea and magnesium sulfate into liquid drops and spray the liquid drops to the material curtain, the liquid drops collide with the moving particles to be coated and solidified on the surfaces of the particles, the enlarged particles fall to the bottom of the drum, the liquid drops are shoveled into the fluidized bed again. The granulating return material is from bulk material obtained by crushing small particles and large particles, and if necessary, part of finished product is used as granulating return material.

The disk granulation is composed of trays with angles and a supporting frame, the inclination angle and the rotation speed of the trays are adjustable, the slurry synthesized by urea and magnesium sulfate is sent to the upper part of the trays through a pipeline, the slurry is continuously and quantitatively added into the trays, the materials of the trays are bonded by the sprayed slurry, the particles are wrapped into granules, the granules grow up gradually as the trays roll, large granules float on the upper part and are continuously discharged from the lower part of the trays due to the obvious classification capacity of the disk granulator, and smaller granules are remained in the trays and bonded with newly added materials at points, and the granulation is continued.

The steel belt granulation is that slurry synthesized by urea and magnesium sulfate is uniformly distributed on a steel belt moving at a constant speed below the steel belt through a granulator distributing device, and a continuous water spraying cooling device is arranged below the steel belt to force materials on the steel belt to be rapidly solidified and cooled in the moving process, so that the purpose of granulation molding is achieved, and hemispherical and flaky urea magnesium sulfate products can be produced.

In a preferred embodiment, the temperature of granulation is 100-120 ℃. The temperature of granulation is typically, but not limited to, 100 deg.C, 105 deg.C, 110 deg.C, 115 deg.C or 120 deg.C.

In a preferred embodiment, the preparation method further comprises the steps of cooling and sieving in sequence after granulation. Cooling means that the temperature of the material is not higher than 40 ℃.

In a preferred embodiment, the urea magnesium sulfate fertilizer with the grain diameter of 2-4mm is obtained by screening.

The urea magnesium sulfate fertilizer prepared by the preparation method contains N25-43 w/w%, Mg 1-8 w/w% and S1-10 w/w%, contains a proper amount of acyl nitrogen, water-soluble magnesium and sulfur, is fully water-soluble, has quick fertilizer effect, and has the advantages of high nitrogen utilization rate, obvious fertilizer effect and the like compared with simple urea.

The urea magnesium sulfate fertilizer is applied as a base fertilizer, an additional fertilizer, a fertilizer raw material or a fertilizer additive in crop planting.

The invention is further illustrated by the following specific examples , but it should be understood that these examples are included merely for purposes of illustration in more detail and are not to be construed as limiting the invention in any way.