Phosphorite powder pellet drying equipment

Abstract

The invention provides ground phosphate rock pellet drying equipment, and belongs to the technical field of phosphorus chemical industry production equipment. According to the equipment, through the design of the material guide inclined plate, the problem that in the prior art, a ground phosphate rock pellet sliding path is prone to being blocked is solved; meanwhile, through the design that the heating device is a combustor, the problems that in the prior art, heat loss is large, and it is difficult to achieve higher quality of the ground phosphate rock pellets are solved. The ground phosphate rock pellet drying equipment comprises a drying furnace for accommodating ground phosphate rock pellets and a heating device for drying the ground phosphate rock pellets, a plurality of material guide inclined plates are fixedly mounted in the drying furnace; in the height direction of the drying furnace, the multiple material guiding inclined plates are sequentially arranged at intervals from top to bottom, and every two vertically-adjacent material guiding inclined plates are arranged in a staggered mode. Each material guide inclined plate inclines downwards and is arranged in a hollowed-out manner; the distance from the lower end of the guide inclined plate to the inner wall of the drying furnace is greater than the diameter of the powdered rock phosphate pellets; the heating device is a combustor, a fire spraying opening of the combustor is directly communicated with the interior of the drying furnace, and fire is sprayed to the lower portion of the material guiding inclined plate.

Description

Technical Field

[0001] The invention belongs to the technical field of phosphorus chemical production equipment, and in particular relates to a phosphate rock powder pellet drying device. Background Art

[0002] Phosphate rock powder pellets are a product that is made by processing phosphate rock powder into a spherical shape through a specific process. At present, high-grade phosphate rock used in the production of yellow phosphorus, especially weathered phosphate rock, will produce a large amount of powder ore during processing and use. This part of phosphate rock powder must be prepared into pellets before it can be used to produce yellow phosphorus. In the existing technology, the production process of phosphate rock powder pellets includes batching, mixing, pelletizing, drying and other processes. Drying is an important process for the production of phosphate rock powder pellets, and the drying device is the key equipment in the drying process of phosphate rock powder.

[0003] A Chinese invention patent with application publication number CN112556318A discloses a high-efficiency drying device for producing phosphate rock powder pellets. The drying device described in the patent heats the pellets in such a way that hot air enters the heating pipe from the right air inlet chamber and is discharged from the left exhaust chamber. The hot air is discharged directly, has a short residence time in the drying section, and has a poor heating effect on the pellets.

[0004] The Chinese utility model patent with authorization announcement number CN215002793U discloses a mineral powder pellet drying device, in which hot air flows from the upper row of heating trough plates into the drying section through the air inlet chamber. Since the upper row of heating trough plates is located on one side of the exhaust chamber and is blocked, the hot air can only flow downward to the next row of heating trough plates, and flow from the next row of heating trough plates to the exhaust chamber and be discharged. The design allows the hot air to form wind flow disturbances between the upper row of heating trough plates and the next row of heating trough plates, so that the hot air stays in the drying section longer and can dry the pellets more fully. Compared with the Chinese invention patent with application publication number CN112556318A, the drying process is more energy-efficient and efficient, and the hot air can carry the evaporated water vapor of the mixed pellets when it is discharged from the exhaust chamber, so the evaporated water vapor in the drying section is discharged in time, further improving the drying effect of the pellets.

[0005] However, the technical solution recorded in the Chinese utility model patent with the authorization announcement number CN215002793U has the following problems:

[0006] 1. Because the longitudinal cross-sectional shape of the guide plate in the guide section and the longitudinal cross-sectional shape of the heating trough plate in the drying section are both inverted V-shaped structures, as production continues, the phosphate rock powder that enters the device together with the phosphate rock powder pellets gradually deposits on the guide plate and the heating trough plate, causing blockage of the guide section and the drying section.

[0007] Second, because the device dries the mineral powder balls by letting the hot air generated by combustion enter the drying section through the air inlet; although the thermal efficiency is improved compared with the technical solution recorded in the Chinese invention patent with publication number CN112556318A, the heat loss is still large and the energy consumption cost is high.

[0008] 3. Because the hot air generated by combustion is sent into the drying section from the air inlet, not only the heat loss is large, but also the moisture on the surface of the pellets cannot be removed quickly, resulting in the mineral powder pellets not being able to quickly form a relatively dry outer shell, and thus not being able to quickly prevent the internal moisture from diffusing outward and eroding the surface of the pellets. Therefore, it is difficult to achieve higher quality for the mineral powder pellets that are dried by sending the hot air generated by combustion into the drying section from the air inlet. Summary of the invention

[0009] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a phosphate rock powder pellet drying equipment, which is used to solve the problems in the prior art that the material guide section and the drying section of the phosphate rock powder pellet drying device are easily blocked as production continues, the heat loss in the drying process is still large, and the dried phosphate rock powder pellets are difficult to achieve higher quality.

[0010] In order to achieve the above-mentioned object and other related objects, the present invention provides a phosphate rock powder pellet drying device, comprising:

[0011] A drying furnace for accommodating phosphate rock powder pellets;

[0012] A heating device, which transmits heat energy to the interior of the drying furnace to dry the phosphate rock powder pellets contained in the drying furnace;

[0013] A plurality of material guiding inclined plates are fixedly installed inside the drying furnace; along the height direction of the drying furnace, the plurality of material guiding inclined plates are arranged in sequence from top to bottom with intervals, and two adjacent material guiding inclined plates are arranged in a staggered manner;

[0014] Each of the guide inclined plates is inclined downward and hollowed out; the distance from the lower end of the guide inclined plate to the inner wall of the drying furnace is greater than the diameter of the phosphate rock pellets;

[0015] The heating device is a burner, and the flame outlet of the burner is directly connected to the interior of the drying furnace, and sprays fire to the bottom of the material guide inclined plate.

[0016] Optionally, a load-bearing beam is fixedly installed inside the drying furnace; the upper end of the material guide inclined plate is fixedly connected to the inner wall of the drying furnace, and the lower part of the material guide inclined plate is overlapped on the load-bearing beam; the material guide inclined plate is formed by a plurality of round bars arranged at intervals.

[0017] Optionally, the flame outlet of the burner is connected to the lower part of the drying furnace.

[0018] Optionally, there are multiple burners, and the multiple burners are separately arranged on two opposite sides of the drying furnace.

[0019] Optionally, the drying furnace is also connected to a dust removal device, and a dust removal port connected to the dust removal device is provided with a cold air valve.

[0020] Optionally, the first temperature sensor detects that when the temperature on the guide inclined plate is lower than a first set value, the burner is controlled to increase the flame spraying through electrical connection; when the temperature is higher than a second set value, the burner is controlled to reduce the flame spraying through electrical connection;

[0021] The second temperature sensor detects that when the temperature of the dust removal port is lower than a third set value, the cold air valve is controlled to be closed through electrical connection; when it is higher than a fourth set value, the cold air valve is controlled to be opened through electrical connection.

[0022] Optionally, the burner has a first pneumatic shut-off valve and a second pneumatic shut-off valve connected in series; when the gas pressure in the burner is lower than 1000Pa, or when the burner's flame outlet does not spray fire, the first pneumatic shut-off valve and the second pneumatic shut-off valve simultaneously cut off the gas supply.

[0023] Optionally, the flame outlet of the burner is flat.

[0024] Optionally, the drying furnace includes a feeding section, a drying section and a unloading section which are arranged in sequence from top to bottom; the material guide inclined plate is arranged in the drying section, and the flame outlet of the burner is connected to the interior of the drying section.

[0025] Optionally, a heat-insulating layer made of high-strength castable material is provided inside the drying section.

[0026] As described above, the phosphate rock powder pellet drying equipment of the present invention has at least the following beneficial effects:

[0027] The phosphate rock powder pellet drying equipment solves the problem in the prior art that, as production continues, the phosphate rock powder that enters the device together with the phosphate rock powder pellets gradually deposits on the guide plates and the heating trough plates, causing blockage in the sliding path of the phosphate rock powder pellets, through the design of the guide ramp. Specifically, after the phosphate rock powder pellets and the phosphate rock powder enter the drying furnace, the phosphate rock powder pellets slide along a downwardly inclined guide ramp to another adjacent, staggered guide ramp until they leave the drying furnace; and the phosphate rock powder falls along the hollow positions on the guide ramp, and will not accumulate on the sliding path of the phosphate rock powder pellets to cause blockage. At the same time, the design of the heating device being a burner solves the problem of large heat loss and difficulty in achieving higher quality of phosphate rock powder pellets in the prior art; specifically, the phosphate rock powder pellets falling from one guide ramp to another guide ramp are directly baked by the flame ejected from the burner nozzle. Compared with indirect hot air baking, not only is the energy consumption cost low, but the direct baking by the flame can quickly remove the moisture on the surface of the phosphate rock powder pellets, so that a relatively dry shell is formed on the surface of the phosphate rock powder pellets, preventing the internal moisture of the phosphate rock powder pellets from diffusing outward and corroding the surface of the pellets, and finally producing higher quality phosphate rock powder pellets. In addition, because the flame directly ejected from the burner nozzle bakes the phosphate rock powder pellets, it also directly ablates the fallen phosphate rock powder, so that the phosphate rock powder adheres to the phosphate rock powder balls, reducing the dust raised by this equipment during production. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Shown is a side view of a phosphate rock powder pellet drying device according to the present invention.

[0029] Figure 2 Shown is a front view of the present invention.

[0030] Figure 3 Shown is a top view of the present invention.

[0031] Figure 4 Shown is a schematic diagram of a burner of the present invention.

[0032] Component number description

[0033] A drying furnace 1, a feeding part 11, a drying part 12, a discharging part 13, a burner 2, a first pneumatic shut-off valve 21, a second pneumatic shut-off valve 22, a flame nozzle 23, a material guide inclined plate 3, a load-bearing beam 4, and a heat-insulating layer 5. DETAILED DESCRIPTION

[0034] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0035] See also Figures 1 to 4. It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0036] The following embodiments are only for illustration purposes and can be combined with each other, and are not limited to the contents presented in the following single embodiments.

[0037] See also Figure 1 The present invention provides a phosphate rock powder pellet drying device, which is similar to a phosphate rock powder pellet drying device disclosed in the Chinese utility model patent with the authorization announcement number CN215002793U in the background technology. The device also includes:

[0038] like Figure 1 and Figure 2 The drying furnace 1 shown is used to accommodate phosphate rock pellets.

[0039] The heating device transmits heat energy to the interior of the drying furnace 1 to dry the phosphate rock powder pellets contained in the drying furnace 1.

[0040] The difference between this device and the prior art is that:

[0041] 1. If Figure 1 and Figure 2 As shown, a plurality of guide ramps 3 are fixedly installed inside the drying furnace 1; along the height direction of the drying furnace 1, the plurality of guide ramps 3 are arranged in sequence from top to bottom, and the two upper and lower adjacent guide ramps 3 are arranged in a staggered manner. For the specific form of the staggered arrangement, please refer to Figure 1 ; Each of the guide inclined plates 3 is inclined downward and hollowed out. There are various hollowing forms, one of which will be described in detail below; the distance from the lower end of the guide inclined plate 3 to the inner wall of the drying furnace 1 is greater than the diameter of the phosphate rock powder pellets to ensure that the phosphate rock powder pellets fall smoothly from the upper guide inclined plate 3 to the lower guide inclined plate 3.

[0042] After the phosphate rock powder pellets and phosphate rock powder enter the drying furnace 1 from above, the phosphate rock powder pellets slide along a downwardly inclined material guide inclined plate 3 to another adjacent, staggered material guide inclined plate 3 until they leave the drying furnace 1 from below; at the same time, the phosphate rock powder falls along the hollow position on the material guide inclined plate 3, and will not accumulate on the sliding path of the phosphate rock powder pellets to cause blockage; the invention solves the problem of a mineral powder pellet drying device disclosed in the Chinese utility model patent with authorization announcement number CN215002793U, in which the phosphate rock powder entering the device together with the phosphate rock powder pellets gradually deposits on the material guide plate and the heating trough plate as production continues, causing the sliding path of the phosphate rock powder pellets to be blocked.

[0043] 2. If Figure 1 and Figure 3 As shown, the heating device is a burner 2, and the flame outlet 23 of the burner 2 is directly connected to the interior of the drying furnace 1, and flames are sprayed below the guide ramp 3. The space below the guide ramp 3 provides sufficient space for the phosphate rock powder pellets and the combustion of the phosphate rock powder; the phosphate rock powder pellets falling from one guide ramp 3 to another guide ramp 3 are directly baked by the flame sprayed from the flame outlet 23 of the burner 2. Compared with the indirect hot air baking, not only is the energy consumption cost low, but the direct baking by the flame can quickly remove the moisture on the surface of the phosphate rock powder pellets, so that a relatively dry shell is formed on the surface of the phosphate rock powder pellets, preventing the moisture inside the phosphate rock powder pellets from diffusing outward to erode the pellet surface, and finally producing higher quality phosphate rock powder pellets.

[0044] In addition, because the flame directly ejected from the burner 23 bakes the phosphate rock pellets while directly ablating the fallen phosphate rock powder, the phosphate rock powder adheres to the phosphate rock pellets, reducing the dust generated by the equipment during production.

[0045] A Chinese utility model patent with authorization announcement number CN215002793U discloses a mineral powder pellet drying device that produces 200 tons of phosphate rock powder pellets. The amount of yellow phosphorus tail gas used in this equipment can produce 960 to 1,200 tons, that is, 40 to 50 tons per hour.

[0046] In another embodiment, see Figure 1 and Figure 2The drying furnace 1 is fixedly installed with a load-bearing beam 4 inside, and the load-bearing beam 4 is an H-shaped steel; the upper end of the guide ramp 3 is fixedly connected to the inner wall of the drying furnace 1, and the fixed connection method can be selected by welding or other methods, which are not described here; the lower part of the guide ramp 3 is overlapped on the load-bearing beam 4, generally, the lower surface of the lower part of the guide ramp 3 is overlapped on the load-bearing beam 4; the advantage of this design method is that the guide ramp 3 has thermal expansion and contraction. When the temperature inside the drying furnace 1 rises, even if the guide ramp 3 expands due to heat, because the lower part of the guide ramp 3 is overlapped on the load-bearing beam 4, the connection position of the guide ramp 3 of this embodiment has space for thermal expansion. Compared with the method in which both ends of the guide ramp 3 are fixed, the probability of loose connection of the guide ramp 3 can be reduced, thereby improving the working reliability of the phosphate rock powder pellet drying equipment.

[0047] like Figure 2 As shown, the hollow form of the guide ramp 3 is that it is composed of a plurality of round bars arranged at intervals. This design method, on the one hand, allows the hollow part in the middle of the guide ramp 3 to have space for expansion due to heat, and on the other hand, the falling phosphate rock powder can smoothly fall between the round bars; the form of multiple round bars arranged at intervals makes it difficult for the falling phosphate rock powder to settle compared to other hollow forms; and the staff can also quickly make a guide ramp 3 of appropriate size by adjusting the number of round bars according to the size of the drying furnace 1.

[0048] In another embodiment, please refer to the figure, because the heat generated by combustion moves upward, the flame port 23 of the burner 2 is connected to the lower part of the guide inclined plate 3 at the bottom of the drying furnace 1, further improving the energy utilization efficiency.

[0049] In another embodiment, see Figure 1 There are multiple burners 2, and the multiple burners 2 are separately arranged on two opposite sides of the drying furnace 1. The specific design method can be: two burner 2 flame ports 23 are arranged below the guide inclined plate 3 at the bottom of the drying furnace 1, and the two flame ports 23 are on one side; two burner 2 flame ports 23 are arranged between the two guide inclined plates 3 at the bottom of the drying furnace 1, and the two flame ports 23 are on the other side; to ensure sufficient drying of the phosphate rock powder pellets.

[0050] In another embodiment, the drying furnace 1 is also connected to a dust removal device to further reduce the dust generated by the equipment. Since the burner 2 is arranged at the lower part of the drying furnace 1, the dust removal device can be arranged at the upper part of the drying furnace 1, which can not only avoid the interference of different components, but more importantly, because the phosphate rock powder floats upward, the dust removal device arranged at the upper part of the drying furnace 1 can better remove the dust; at the same time, in order to avoid the high-temperature gas inside the drying furnace 1 to damage the bag of the dust removal device, a cold air valve will be provided at the dust removal port connected to the dust removal device.

[0051] In another embodiment, in order to accurately control the burner 2 and the cold air valve mentioned above, the phosphate rock powder pellet drying equipment further includes:

[0052] The first temperature sensor detects that when the temperature on the guide inclined plate 3 is lower than the first set value, the burner 2 is controlled to increase the flame through electrical connection; when it is higher than the second set value, the burner 2 is controlled to reduce the flame through electrical connection; the first set value is less than the second set value, specifically, the first set value is 450°C, and the second set value is 550°C.

[0053] The second temperature sensor detects that when the temperature of the dust removal port is lower than the third set value, the cold air valve is controlled to be closed through electrical connection; when it is higher than the fourth set value, the cold air valve is controlled to be opened through electrical connection; the third set value is less than the fourth set value, specifically, the third set value is 80°C and the fourth set value is 120°C.

[0054] In another embodiment, see Figure 4 The burner 2 has a first pneumatic shut-off valve 21 and a second pneumatic shut-off valve 22 connected in series; when the gas pressure in the burner 2 is lower than 1000Pa, or when the flame port 23 of the burner 2 does not spray fire, the first pneumatic shut-off valve 21 and the second pneumatic shut-off valve 22 simultaneously cut off the gas supply; through the design of the two-stage pneumatic shut-off valve, the safety of the phosphate rock powder pellet drying equipment is significantly improved.

[0055] In another embodiment, see Figure 1 The flame outlet 23 of the burner 2 is flat, which ensures that the flame is longer and can more easily dry the phosphate rock pellets in the space below the guide inclined plate 3.

[0056] In another embodiment, see Figure 1 The drying furnace 1 comprises a feeding part 11, a drying part 12 and a discharging part 13 which are arranged in sequence from top to bottom.

[0057] The feed section 11 may be as follows Figure 1The upper hopper shown may also be the same as the feeding section described in the Chinese utility model patent specification with authorization announcement number CN215002793U, or other shapes.

[0058] The drying section 12 may be composed of Figure 1 and Figure 2 The drying section 12 is composed of multiple drying sections, which are connected by flanges. The material guide inclined plate 3 is arranged in the drying section 12, and the flame outlet 23 of the burner 2 is connected to the interior of the drying section 12.

[0059] The blanking portion 13 can also be the same as the blanking section described in the Chinese utility model patent specification with authorization announcement number CN215002793U. For the specific structure of the blanking section, please refer to paragraphs 0048-0052 of the utility model specification.

[0060] In another embodiment, see Figure 1 and Figure 2 The interior of the drying section 12 is provided with an insulation layer 5 made of high-strength castable to effectively ensure the temperature in the drying furnace 1; the high-strength castable is an amorphous refractory material made of refractory material with a certain amount of binder added, having good fluidity and stability and constructed by a pouring method; the high-strength castable is usually composed of high-strength aggregate, powder mineral additives and binders.

[0061] In other embodiments, Figure 2 As shown, the gap between the two round bars is to achieve the following technical effect: the phosphate rock powder pellets with a diameter greater than 5 mm cannot leak from the gap, but slide down one guide inclined plate 3 to the next guide inclined plate 3 until they slide to the unloading part 13. The phosphate rock powder pellets dried by the drying furnace 1, those that meet the requirements enter the next process, and those with a smaller diameter that do not meet the requirements are sent back to the molding machine to ensure full utilization of the phosphate rock powder.

[0062] In summary, the present invention solves the problem in the prior art that as production continues, the phosphate rock powder that enters the device together with the phosphate rock powder pellets gradually deposits on the guide plate and the heating trough plate, causing the phosphate rock powder pellets to slide and block the path; at the same time, the heating device is designed as a burner 2, which solves the problem in the prior art that the heat loss is large and the phosphate rock powder pellets are difficult to achieve higher quality; and because the flame directly ejected from the burner 23 of the burner 2 bakes the phosphate rock powder pellets while directly ablating the fallen phosphate rock powder, the phosphate rock powder is attached to the phosphate rock powder balls, reducing the dust of the equipment during production. Therefore, the present invention effectively overcomes the shortcomings of the prior art and has a high industrial utilization value.

[0063] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A phosphate rock powder pellet drying device, comprising: A drying furnace for accommodating phosphate rock powder pellets; A heating device, which transmits heat energy to the interior of the drying furnace to dry the phosphate rock powder pellets contained in the drying furnace; Features: A plurality of material guiding inclined plates are fixedly installed inside the drying furnace; along the height direction of the drying furnace, the plurality of material guiding inclined plates are arranged in sequence from top to bottom with intervals, and two adjacent material guiding inclined plates are arranged in a staggered manner; Each of the guide inclined plates is inclined downward and hollowed out; the distance from the lower end of the guide inclined plate to the inner wall of the drying furnace is greater than the diameter of the phosphate rock pellets; The heating device is a burner, and the flame outlet of the burner is directly connected to the interior of the drying furnace, and sprays fire to the bottom of the material guide inclined plate.

2. The phosphate rock powder pellet drying equipment according to claim 1, characterized in that: A load-bearing beam is fixedly installed inside the drying furnace; The upper end of the material guiding inclined plate is fixedly connected to the inner wall of the drying furnace, and the lower part of the material guiding inclined plate is overlapped on the load-bearing beam; The material guiding inclined plate is formed by a plurality of round bars arranged at intervals.

3. The phosphate rock powder pellet drying equipment according to claim 1, characterized in that: The flame-spraying port of the burner is connected to the lower part of the drying furnace.

4. The phosphate rock powder pellet drying equipment according to claim 3, characterized in that: There are a plurality of burners, and the burners are separately arranged on two opposite sides of the drying furnace.

5. The phosphate rock powder pellet drying equipment according to claim 1, characterized in that: The drying furnace is also connected to a dust removal device, and a dust removal port connected to the dust removal device is provided with a cold air valve.

6. The phosphate rock powder pellet drying equipment according to claim 5, characterized in that: Also includes: The first temperature sensor detects that when the temperature on the guide inclined plate is lower than a first set value, the burner is controlled to increase the flame spraying through electrical connection; when the temperature is higher than a second set value, the burner is controlled to reduce the flame spraying through electrical connection; The second temperature sensor detects that when the temperature of the dust removal port is lower than a third set value, the cold air valve is controlled to be closed through electrical connection; when it is higher than a fourth set value, the cold air valve is controlled to be opened through electrical connection.

7. The phosphate rock powder pellet drying equipment according to claim 1, characterized in that: The burner has a first pneumatic shut-off valve and a second pneumatic shut-off valve connected in series; When the gas pressure in the burner is lower than 1000 Pa, or when the burner does not emit fire, the first pneumatic shut-off valve and the second pneumatic shut-off valve simultaneously cut off the gas supply.

8. The phosphate rock powder pellet drying equipment according to claim 1, characterized in that: The flame-spraying port of the burner is flat.

9. The phosphate rock powder pellet drying equipment according to claim 1, characterized in that: The drying furnace comprises a feeding part, a drying part and a discharging part which are arranged in sequence from top to bottom; The material guide inclined plate is arranged in the drying part, and the flame-spraying port of the burner is communicated with the interior of the drying part.

10. The phosphate rock powder pellet drying equipment according to claim 9, characterized in that: The interior of the drying section is provided with a heat-insulating layer made of high-strength castable material.

Images