Coke ore pellet for industrial yellow phosphorus production and preparation method thereof

Abstract

The invention relates to a coke ore pellet for industrial yellow phosphorus production and a preparation method of the coke ore pellet. The preparation method comprises the following steps: S1, respectively crushing and screening coke powder and ground phosphate rock; s2, fully stirring and mixing the screened coke powder and ground phosphate rock with industrial phosphoric acid to obtain an intermediate mixed material; s3, uniformly adding industrial water into the intermediate mixed material obtained in the S2 through a spraying device, starting stirring at the same time, and uniformly stirring to obtain a final mixed material; and S4, the final mixed material obtained in the S3 is pressed into coke ore pellets through a double-roller press, and then the coke ore pellets are put into a plate type dryer to be dried and shaped. According to the preparation method of the coke ore pellets, the coke powder and the ground phosphate rock serve as raw materials, the industrial phosphoric acid serves as the binding agent and the activating agent, the prepared coke ore pellets are low in cost, high in compressive strength in a high-temperature area and high in pelletizing rate and can serve as a raw material for producing industrial yellow phosphorus, and cost reduction and efficiency improvement of yellow phosphorus production are achieved.

Description

Technical Field

[0001] This invention belongs to the field of inorganic phosphorus chemical product processing technology, specifically relating to a coke ore pellet for industrial yellow phosphorus production and its preparation method. Background Technology

[0002] The raw materials for the electric furnace method of producing industrial yellow phosphorus mainly include phosphate rock, coke, and silica. Phosphate rock and coke are used in large quantities. However, the mining, transportation, and crushing of phosphate rock generate a large amount of phosphate rock powder, and the crushing and transportation of coke also produce a certain amount of coke powder. If this dust is not consumed in a timely manner, it will not only cause environmental pollution but also waste coke and phosphate rock resources. Therefore, it is urgent to find a method to simultaneously consume both coke powder and phosphate rock powder.

[0003] Phosphate rock and coke used in the production of industrial yellow phosphorus need to be within a certain particle size range. The particle size of the raw materials directly affects the state of the furnace charge at high temperatures, thus affecting the stable production of yellow phosphorus. Only raw materials with the required particle size can produce qualified industrial yellow phosphorus while reducing the generation of mud phosphorus. Therefore, phosphate rock powder and coke powder cannot be directly used in the production of yellow phosphorus.

[0004] To address the aforementioned issues, some researchers have mixed phosphate rock powder or coke powder with binders and pressed it into pellets of a specific particle size for industrial production. For example, Chinese patent CN 110683524A discloses "A binder and a binder-based phosphate rock powder pelletizing method." This method has limitations in pelletizing, relying primarily on the binder to maintain the pellet's skeleton and strength. The binder's main component is inorganic, with a complex composition and high addition ratio, resulting in high cost for the pellets produced. Furthermore, the increased addition of inorganic binder leads to increased slag, hindering cost reduction and efficiency improvement in yellow phosphorus production. Chinese patent CN 120366568A discloses "A method for preparing dust-removing coke powder by cold pressing into pellets." This method involves mixing coke powder with a carbon composite binder and pressing it into pellets for steelmaking production. This method is a cold-pressing pelletizing process; the patent does not specify the compressive strength of the pellets in high-temperature zones, and the carbon composite binder is prone to decomposition at high temperatures. Therefore, pellets prepared by this method are difficult to apply to smelting industries requiring high temperatures.

[0005] Therefore, in order to solve the problems existing in the utilization of phosphate rock powder and coke powder resources, it is necessary to develop a method for the coupled preparation of phosphate rock powder and coke powder into pellets, which can reduce the pelletizing cost, enable the pellets to have high strength at high temperatures, and at the same time consume phosphate rock powder and coke powder, reduce environmental pollution and improve resource utilization. Summary of the Invention

[0006] The purpose of this invention is to provide a coke ore pellet for the production of industrial yellow phosphorus. The prepared coke ore pellet has low cost, high compressive strength in the high-temperature zone, and high pelletizing rate. It can be used as a raw material for the production of industrial yellow phosphorus, thereby reducing costs and increasing efficiency in the production of yellow phosphorus. Moreover, the preparation method is simple.

[0007] The technical solution adopted by this invention to solve the above problems is: a method for preparing coke ore pellets for industrial yellow phosphorus production, comprising the following steps: S1. Crush and screen the coke powder and phosphate rock powder separately; S2. Thoroughly mix the sieved coke powder and phosphate rock powder with industrial phosphoric acid to obtain an intermediate mixture. S3. Add industrial water evenly to the intermediate mixture in S2 through a spraying device, and start stirring at the same time to obtain the final mixture. S4. The final mixture from S3 is pressed into coke pellets using a roller press, and then placed into a plate dryer for drying and shaping.

[0008] Preferably, in step S1, the phosphate rock powder is crushed to a particle size ≤ 1 mm, and the coke powder is crushed to a particle size ≤ 3 mm.

[0009] Preferably, the mass ratio of coke powder to phosphate rock powder in step S2 is 1:0.9-1.5.

[0010] Preferably, the mass fraction of industrial phosphoric acid in step S2 is 85%, and its addition amount is 4-6% of the total mass of all materials.

[0011] Preferably, the mixing time in step S2 is 15-20 minutes.

[0012] Preferably, in step S3, the amount of industrial water added is 9-11% of the total mass of all materials, and the stirring time is 8-10 minutes.

[0013] Preferably, the temperature of the plate dryer in step S4 is 120-150℃, and the drying time is 40-60 minutes.

[0014] Another object of the present invention is to provide coke ore pellets for the production of industrial yellow phosphorus, which are prepared by the above-described method for preparing coke ore pellets for the production of industrial yellow phosphorus.

[0015] Preferably, the coke pellets have a particle size of 1.5 cm.

[0016] Compared with the prior art, the advantages of the present invention are as follows: (1) The method for preparing coke pellets for industrial yellow phosphorus production of the present invention uses phosphate rock powder, coke powder and industrial water as raw materials, and industrial phosphoric acid as binder and activator. The prepared coke pellets are low in cost, have high compressive strength in high temperature zone and high pelleting rate, and can be used as raw materials for the production of industrial yellow phosphorus, thereby reducing costs and increasing efficiency in yellow phosphorus production. The preparation method is also simple.

[0017] (2) This invention prepares coke powder and phosphate rock powder into raw materials for industrial yellow phosphorus production, thereby achieving the coupled utilization of phosphate rock powder and coke powder, consuming a large amount of coke powder and phosphate rock powder, thereby reducing dust pollution, protecting the environment and making efficient use of resources, and reducing the production cost of yellow phosphorus.

[0018] (3) The present invention uses industrial phosphoric acid as a binder and activator for pelletizing coke, which can not only improve the grade of phosphate rock powder, but also activate the phosphate rock powder, so that it can bond more fully with coke powder, and greatly increase the compressive strength of the pellets at high temperature. Attached Figure Description

[0019] Figure 1 This is a process flow diagram of coke pellets used in the production of industrial yellow phosphorus according to the present invention. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] like Figure 1 The diagram shows the process flow chart for producing coke pellets for industrial yellow phosphorus according to the present invention. Example 1

[0022] A method for preparing coke pellets for industrial yellow phosphorus production includes the following steps: S1. The phosphate rock powder and coke powder are crushed and screened, wherein the particle size of the phosphate rock powder is controlled at 0-1 mm and the particle size of the coke powder is controlled at 0-3 mm. S2. Take the sieved coke powder and phosphate rock powder from S1 and mix them evenly at a mass ratio of 1:1. Then add 85% industrial phosphoric acid and mix evenly for 15 minutes. The coke powder and phosphate rock powder account for 85.9% of the total mass of all materials, and the industrial phosphoric acid accounts for 4.1% of the total mass of all materials. S3. Industrial water is evenly sprayed into the mixture from S2 using a spraying device, while stirring for 8 minutes. The industrial water accounts for 10% of the total mass of all materials. S4. The mixture from S3 is pressed into coke ore pellets with a particle size of 1.5cm using a roller press, and then placed into a plate dryer for drying and solidification to obtain the finished coke ore pellets; wherein the drying temperature is 120℃ and the drying time is 60 minutes. Example 2

[0023] A method for preparing coke pellets for industrial yellow phosphorus production includes the following steps: S1. The phosphate rock powder and coke powder are crushed and screened, wherein the particle size of the phosphate rock powder is controlled at 0-1 mm and the particle size of the coke powder is controlled at 0-2 mm. S2. Take the sieved coke powder and phosphate rock powder from S1 and mix them evenly at a mass ratio of 1:1.2. Then add 85% industrial phosphoric acid and mix evenly for 15 minutes. The coke powder and phosphate rock powder account for 84.5% of the total mass of all materials, and the industrial phosphoric acid accounts for 6% of the total mass of all materials. S3. Industrial water is evenly sprayed into the mixture from S2 using a spraying device, while stirring for 10 minutes. The industrial water accounts for 9.5% of the total mass of all materials. S4. The mixture from S3 is pressed into coke pellets with a particle size of 1.5 cm using a roller press, and then placed into a plate dryer for drying and solidification to obtain the finished coke pellets; wherein the drying temperature is 150℃ and the drying time is 40 minutes. Example 3

[0024] A method for preparing coke pellets for industrial yellow phosphorus production includes the following steps: S1. The phosphate rock powder and coke powder are crushed and screened, wherein the particle size of the phosphate rock powder is controlled at 0-1 mm and the particle size of the coke powder is controlled at 0-1 mm. S2. Take the sieved coke powder and phosphate rock powder from S1 and mix them evenly at a mass ratio of 1:1.5. Then add 85% industrial phosphoric acid and mix evenly for 20 minutes. The coke powder and phosphate rock powder account for 84% of the total mass of all materials, and the industrial phosphoric acid accounts for 5% of the total mass of all materials. S3. Industrial water is evenly sprayed into the mixture from S2 using a spraying device, while stirring for 10 minutes. The industrial water accounts for 11% of the total mass of all materials. S4. The mixture from S3 is pressed into coke pellets with a particle size of 1.5 cm using a roller press, and then placed into a plate dryer for drying and solidification to obtain the finished coke pellets; wherein the drying temperature is 130℃ and the drying time is 50 minutes.

[0025] Comparative Example 1 Compared with Example 3, the only difference is that the mass ratio of coke powder to phosphate rock powder in step S2 is 1:0.8, while other parameters and operating steps are the same as in Example 3.

[0026] Comparative Example 2 Compared with Example 3, the only difference is that in step S2, coke powder and phosphate rock powder account for 86% of the total mass of all materials, and 85% of industrial phosphoric acid accounts for 3% of the total mass of all materials. Other parameters and operating steps are the same as in Example 3.

[0027] Comparative Example 3 Compared with Example 3, the only difference is that in step S2, coke powder and phosphate rock powder account for 87% of the total mass of all materials, and in step S3, industrial water accounts for 8% of the total mass of all materials. Other parameters and operating steps are the same as in Example 3.

[0028] Comparative Example 4 Compared with Example 3, the only difference is that the 85% industrial phosphoric acid by mass fraction is replaced with the binder of Chinese patent CN110683524A (CaO 24%, P2O5 26%, SiO2 30%, Al2O3 20%). The coke pellets obtained in Examples 1-3 and Comparative Examples 1-4 were heated at 300℃, 500℃, 800℃ and 1000℃ respectively in the absence of oxygen for 60 minutes. After cooling, their compressive strength (the ability of a single pellet to resist breakage under pressure) was measured according to GB / T13465.3-2002. The results are shown in Table 1. Table 1 shows the compressive strength comparison of Examples 1-3 and Comparative Examples 1-4 at different temperatures.

[0029] As shown in the table above, the coke pellets prepared in Examples 1 to 3 can maintain high strength in all temperature ranges, especially at a high temperature of 1000℃, where the pellet strength can be maintained at more than 300N, and can be used for the production of industrial yellow phosphorus by electric furnace method. In Comparative Example 1, the addition ratio of phosphate rock powder was low, which prevented the formation of a stable three-dimensional skeleton within the pellets and the complete encapsulation of coke powder. When the temperature reached 1000℃, the three-dimensional skeleton was destroyed by the high temperature, resulting in a significant reduction in strength. In Comparative Example 2, the addition amount of industrial phosphoric acid, which acts as a binder and activator, was low, which failed to effectively combine the phosphate rock powder and coke powder, leading to insufficient strength in various temperature ranges. In Comparative Example 3, the addition amount of industrial water was low, which prevented the phosphate rock powder, coke powder, and industrial phosphoric acid from being fully and evenly mixed during material stirring. Due to uneven material distribution within the coke pellets, a stable three-dimensional skeleton was difficult to form during drying and shaping, resulting in low strength in various ranges. In Comparative Example 4, the industrial phosphoric acid was replaced with the binder in Chinese Patent CN 110683524A. Comparing the compressive strength in various temperature ranges, it can be seen that the structure of the pellets is still destroyed by high temperature, resulting in a significant reduction in strength at high temperatures. Furthermore, the binder in Chinese Patent CN 110683524A is mainly composed of inorganic substances, with complex composition and high cost.

[0030] In addition to the above embodiments, the present invention also includes other embodiments. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of the present invention.

Claims

1. A method for producing coke-ore pellets for industrial yellow phosphorus production, characterized by: It comprises the following steps: S1, coke powder and phosphate rock powder are respectively crushed and sieved; S2, the sieved coke powder and phosphate rock powder are fully stirred and mixed with industrial phosphoric acid to obtain an intermediate mixture; S3, industrial water is uniformly added to the intermediate mixture of S2 through a spraying device, and stirring is started to obtain a final mixture; S4, the final mixture of S3 is pressed into coke ore pellets by a roller press, and then put into a plate dryer for drying and shaping.

2. The method of producing coke-ore pellets for industrial yellow phosphorus production according to claim 1, characterized by the fact that: In S1, the phosphate rock powder is crushed to a particle size of ≤1mm, and the coke powder is crushed to a particle size of ≤3mm.

3. The method of producing coke-ore pellets for industrial yellow phosphorus production according to claim 1, characterized by the fact that: In S2, the mass ratio of coke powder to phosphate rock powder is 1:0.9-1.

5.

4. The method of producing the coke ore pellet for industrial yellow phosphorus production according to claim 1, characterized in that: In S2, the mass fraction of industrial phosphoric acid is 85%, and the addition amount is 4-6% of the total mass of all materials.

5. The method of producing the coke ore pellet for industrial yellow phosphorus production according to claim 1, characterized in that: In S2, the stirring and mixing time is 15-20 minutes.

6. The method of producing the coke-ore pellet for industrial yellow phosphor production according to claim 1, characterized in that: In S3, the addition amount of industrial water is 9-11% of the total mass of all materials, and the stirring time is 8-10 minutes.

7. The method of producing the coke-ore pellet for industrial yellow phosphor production according to claim 1, characterized in that: In S4, the temperature of the plate dryer is 120-150℃, and the drying time is 40-60 minutes.

8. A coke ore pellet for industrial yellow phosphorus production, characterized by: The coke ore pellets for industrial yellow phosphorus production are prepared by the preparation method of any one of claims 1-7.

9. The ore sinter for industrial yellow phosphorus production according to claim 8, characterized in that: The particle size of the coke ore pellets is 1.5cm-2.5cm.

Images