Unsteady-state material continuous pneumatic conveying system, control method and steel smelting production line

Abstract

This invention provides a continuous pneumatic conveying system, control method, and steel smelting production line for unsteady materials, belonging to the field of steel smelting technology. The control method includes: acquiring the pressure value at the material outlet of the vertical shaft furnace and the pressure value inside the conveying tank; comparing the pressure value at the material outlet of the vertical shaft furnace with the pressure value inside the conveying tank to obtain a first comparison result; if the first comparison result exceeds a first preset pressure threshold, adjusting the output pressure of a first pressure gas source until the first comparison result meets the first preset pressure threshold. This invention prioritizes maintaining the gas pressure inside the conveying tank approximately equal to the gas pressure at the discharge port of the vertical shaft furnace to reduce the exchange of reducing gas and conveying gas within the vertical shaft furnace, controlling the conveying gas flow rate within a reasonable range, thus ensuring a stable flow rate of unsteady materials during conveying. This adapts to the smelting process characteristics of continuous discharge from the vertical shaft furnace and intermittent feeding from the electric arc furnace, achieving coupled and coordinated production of the vertical shaft furnace and the electric arc furnace, improving production efficiency, and reducing energy consumption.

Description

Technical Field

[0001] This invention relates to the field of metallurgical technology, and in particular to a continuous pneumatic conveying system for unsteady materials, a control method, and an iron and steel smelting production line. Background Technology

[0002] Direct reduction ironmaking in shaft furnaces uses gases such as natural gas, coke oven gas, hydrogen, or carbon monoxide as raw materials. Through purification, heating, or reforming, a mixture of reducing gases is obtained, which is then used to reduce iron-containing raw materials to produce high-quality direct reduced iron. The reduction product has high iron content, moderate carbon content, and few harmful impurities, making it an excellent raw material for smelting high-quality steel and capable of completely or partially replacing scrap steel. Direct reduction in shaft furnaces does not directly use coke or coal; iron-containing raw materials can be iron ore powder, artificial briquettes, pellets, or natural lumps. It is a high-quality, low-consumption, and low-pollution iron and steel metallurgical process, one of the world's most advanced iron and steel metallurgical technologies, and a major pathway to achieving low-carbon smelting in future steel production.

[0003] Direct reduced iron (DRI) produced by vertical shaft furnaces is a solid particulate material containing metallic iron and slag. It has a high bulk density, a particle size of approximately 6mm-20mm, and contains a small amount of dust. Due to its numerous internal pores, DRI is also known as sponge iron. Freshly discharged DRI from the vertical shaft furnace is at a high temperature and has high chemical reactivity. Upon contact with air or moisture, it undergoes vigorous oxidation and exothermic reactions, or generates hydrogen gas, resulting in a flame or hydrogen explosion. Based on the temperature at which DRI is produced, it is classified into cold DRI (CDRI) and hot DRI (HDRI). Traditional vertical shaft furnace DRI is cooled to approximately ≤80℃ before being discharged from the furnace, or it is mechanically pressed into large blocks and then cooled to room temperature to reduce the oxidation rate and prevent overheating and spontaneous combustion. Modern low-carbon smelting processes typically involve adding hot direct reduced iron (DRI) produced in a shaft furnace to an electric arc furnace for steelmaking without cooling. This fully utilizes the physical heat of the DRI, reducing electric arc furnace power consumption and electrode consumption. It also minimizes iron loss due to oxidation and dust during the DRI cooling process. Current technologies often use hot-chain conveyors to transport hot DRI, but these conveyors have short transport distances, require significant maintenance, and have stringent requirements regarding space, height, and angle. The use of inert gas to isolate the DRI from air and moisture results in high gas consumption and poses an environmental risk of dust spillage. Some plants employ pneumatic conveying technology for hot DRI, which offers good sealing and allows for the recycling of transport gas after dust removal and cooling. However, pneumatic conveying of large-particle-size, high-density, high-temperature, and highly reactive unsteady-state hot DRI is extremely challenging, making pressure control difficult, especially adapting to changes in shaft furnace pressure and output. Therefore, it is necessary to develop a new process and equipment to take over the hot direct reduced iron produced in the vertical shaft furnace and charge it into the electric furnace under closed conditions, while adapting to the smelting process characteristics of continuous production in the vertical shaft furnace and intermittent production in the electric furnace. Summary of the Invention

[0004] This invention provides a continuous pneumatic conveying system, control method, and steel smelting production line for unsteady materials, in order to solve the technical problems such as poor coupling and collaborative production mechanism between vertical furnace and electric furnace, which leads to reduced production efficiency and increased energy consumption.

[0005] On one hand, the present invention provides a control method for a continuous pneumatic conveying system for unsteady-state materials, the continuous pneumatic conveying system comprising: A conveying tank, wherein the material inlet of the conveying tank is connected to the material outlet of the vertical furnace; A hot delivery pipeline, wherein the material inlet of the hot delivery pipeline is connected to the material outlet of the conveying tank; A charging module, used to load material from the hot conveying pipe into the electric furnace, wherein the material outlet of the hot conveying pipe is connected to the material inlet of the charging module; and A first pressure gas source is connected to the heat delivery pipeline to supply delivery gas to the heat delivery pipeline. The first pressure gas source is also connected to the delivery tank to adjust the pressure value inside the delivery tank. The control method includes: Obtain the pressure value at the material outlet of the vertical furnace and the pressure value inside the conveying tank; The pressure value at the material outlet of the vertical furnace is compared with the pressure value inside the conveying tank to obtain a first comparison result. If the first comparison result exceeds a first preset pressure threshold, the output pressure of the first pressure gas source is adjusted until the first comparison result meets the first preset pressure threshold.

[0006] In an optional embodiment of the present invention, the continuous pneumatic conveying system further includes a second pressure gas source, which is connected to the conveying tank; The control method further includes: Gas is also supplied to the delivery tank through the second pressure gas source until the first comparison result meets the second preset pressure threshold. The first preset pressure threshold includes the second preset pressure threshold, and the range of the second preset pressure threshold is smaller than the range of the first preset pressure threshold.

[0007] In an optional embodiment of the present invention, after comparing the pressure value at the material outlet of the vertical furnace with the pressure value inside the conveying tank to obtain the first comparison result, the method further includes: If the first comparison result exceeds the third preset pressure threshold, the height of the material layer in the conveying tank is adjusted until the first comparison result meets the third preset pressure threshold. The first preset pressure threshold includes the third preset pressure threshold, and the range of the third preset pressure threshold is smaller than the range of the first preset pressure threshold.

[0008] In an optional embodiment of the present invention, before the continuous pneumatic conveying system starts conveying, the pressure value of the conveying gas supplied by the first pressure gas source to the hot conveying pipeline is compared with the pressure value in the conveying tank to obtain a second comparison result. If the second comparison result exceeds a fourth preset pressure threshold, the conveying tank is pressurized by the first pressure gas source until the second comparison result meets the fourth preset pressure threshold. The first preset pressure threshold includes the fourth preset pressure threshold, and the range of the fourth preset pressure threshold is smaller than the range of the fourth preset pressure threshold.

[0009] In an optional embodiment of the present invention, adjusting the output pressure of the first pressure gas source includes: Obtain the pressure loss value from the outlet of the first pressure gas source to the inlet of the hot delivery pipeline; The output pressure of the first pressure gas source is determined based on the pressure value at the material outlet of the vertical furnace and the pressure loss value from the first pressure gas source to the gas inlet of the hot delivery pipeline.

[0010] In an optional embodiment of the present invention, the continuous pneumatic conveying system further includes a conveying gas return pipe, the return pipe being connected to the outlet of the first pressure gas source and the inlet of the first pressure gas source. The control method further includes: Obtain the outlet flow rate of the first pressure gas source and the theoretical flow rate of the transport gas in the heat delivery pipeline; If the outlet flow rate of the first pressure gas source is greater than the theoretical flow rate of the conveyed gas, and the difference between the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveyed gas exceeds a preset flow difference threshold, then a portion of the outlet flow rate of the first pressure gas source is returned to the inlet of the first pressure gas source through the return pipe until the flow difference between the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveyed gas meets the preset flow threshold. The theoretical flow rate of the conveying gas is negatively correlated with the solid-to-gas ratio setting of the pneumatic conveying system and the standard volume density of the conveying gas, and positively correlated with the discharge flow rate of the material outlet of the vertical furnace.

[0011] In an optional embodiment of the present invention, the control method further includes: Obtain the verification flow rate of the delivery gas, and adjust the actual flow rate of the delivery gas input from the first pressure gas source to the hot delivery pipeline according to the verification flow rate of the delivery gas; The verification flow rate of the conveying gas is positively correlated with the energy conversion coefficient, the discharge flow rate of the material outlet of the vertical furnace, the specific heat capacity of the material in the hot conveying pipeline, and the temperature change value after the material in the hot conveying pipeline is conveyed. The verification flow rate of the conveying gas is negatively correlated with the constant pressure heat capacity of the conveying gas, the temperature change value after the conveying gas in the hot conveying pipeline is conveyed, and the standard volume density of the conveying gas.

[0012] In an optional embodiment of the present invention, the verification flow rate of the delivery gas is expressed as V. 校核 ,but V 校核 =k*(Q 物料 *Cp 物料 *△T 物料 ) / (ρ*Cp 输送气 *△T 输送气 ) in, k is the energy conversion coefficient, a theoretical or empirical value; Q 物料 The discharge flow rate of the unsteady material discharged from the material outlet of the vertical furnace; Cp 物料 The specific heat capacity of the unsteady material; Cp 输送气 The constant-pressure heat capacity of the transported gas; △T 物料 The temperature change value after the material is transported in the hot delivery pipeline is completed; △T 输送气 The value representing the temperature change after the gas in the hot delivery pipeline has been delivered. ρ is the standard bulk density of the transported gas, in kg / Nm³. 3 .

[0013] In an optional embodiment of the present invention, the unsteady material is HDRI particles.

[0014] In an optional embodiment of the present invention, the hot delivery pipeline is provided with a main inlet for conveying gas and a supplementary inlet for conveying gas. Along the conveying direction of the hot delivery pipeline, the main inlet for conveying gas is close to the material inlet of the hot delivery pipeline, and the supplementary inlet for conveying gas is far away from the material inlet of the hot delivery pipeline. The first pressure gas source is connected to the main inlet for conveying gas and the supplementary inlet for conveying gas respectively. The control method further includes: Determine the pressure difference between the pressure value at the main inlet of the conveying gas and the pressure value at the supplementary inlet of the conveying gas; The flow rate ratio of the first pressure gas source inputting into the main inlet and the supplementary inlet of the conveying gas is adjusted according to the pressure difference of the conveying gas. The flow rate of the conveying gas input to the conveying gas replenishment inlet of the first pressure gas source is positively correlated with the pressure difference of the conveying gas.

[0015] In an optional embodiment of the present invention, the pressure difference between the material outlet pressure of the vertical furnace and the pressure of the conveying tank is ΔP, where ΔP = |P| 竖炉 -P 输送罐 |,△P∝g(Q 输送物料 -Q 物料 ), △P∝f(H 料位高度 ), Q 输送物料 =Q(r 转速 ); in, P 竖炉 The pressure value at the material outlet of the vertical shaft furnace; P输送罐 The pressure value inside the delivery tank; H 料位高度 The material level height inside the conveying tank; r 转速 To transmit the rotational speed of the rotary valve; Q 输送物料 The discharge flow rate of the unsteady material discharged from the conveying tank; Q 物料 The discharge flow rate of the unsteady material discharged from the material outlet of the vertical furnace.

[0016] In this embodiment, the unsteady material is HDRI particles.

[0017] In an optional embodiment of the present invention, along the conveying direction of the hot delivery pipeline, the hot delivery pipeline includes a straight section and a vertical section connected in sequence, the vertical section is vertically upward, the delivery gas supplement inlet is located at the bottom of the vertical section, and the delivery gas main inlet is located at the beginning of the straight section.

[0018] In an optional embodiment of the present invention, the loading module includes an intermediate tank, a loading tank, and a hot material bin connected sequentially along the material flow direction. The hot delivery pipe is connected to the inlet of the intermediate tank. The intermediate tank is used to separate materials and convey gas, and the loading tank is used to depressurize the materials.

[0019] On the other hand, this application also provides a continuous pneumatic conveying system for unsteady-state materials, used to implement the control method described in any of the preceding claims, the continuous pneumatic conveying system comprising: A conveying tank, wherein the material inlet of the conveying tank is connected to the material outlet of the vertical furnace; A hot delivery pipeline, wherein the material inlet of the hot delivery pipeline is connected to the material outlet of the delivery tank. A charging module, used to load material from the hot conveying pipe into the electric furnace, wherein the material outlet of the hot conveying pipe is connected to the material inlet of the charging module; and A first pressure gas source is connected to the hot delivery pipeline to supply delivery gas to the hot delivery pipeline. The first pressure gas source is also connected to the delivery tank to adjust the pressure value of the delivery tank. The control method includes: Obtain the pressure value at the material outlet of the vertical furnace and the pressure value inside the conveying tank; The pressure value at the material outlet of the vertical furnace is compared with the pressure value inside the conveying tank to obtain a first comparison result. If the first comparison result exceeds a first preset pressure threshold, the output pressure of the first pressure gas source is adjusted until the first comparison result meets the first preset pressure threshold.

[0020] In an optional embodiment of the present invention, the loading module includes an intermediate tank, a loading tank, and a hot material silo that are connected sequentially along the material flow direction. The hot delivery pipe is connected to the inlet of the intermediate tank. The intermediate tank is used to separate materials and convey gas. The loading tank is used to depressurize the materials. The hot material silo is used to load the depressurized materials into the electric furnace.

[0021] In an optional embodiment of the present invention, after the conveying gas and unstable materials are separated in the intermediate tank, they are sent to the first pressure gas source for pressurization after dust removal, cooling and demisting, so as to be recycled.

[0022] Alternatively, the dust removal of the conveyed gas can be carried out using either dry or wet dust removal methods.

[0023] In an optional embodiment of the present invention, the conveying gas, after being pressurized by the first pressure gas source, is then conveyed to the hot delivery pipeline to convey unsteady materials.

[0024] Optionally, the delivery gas pressurized by the first pressure gas source is heated by a heating furnace before being delivered to the heat delivery pipeline.

[0025] In an optional embodiment of the present invention, a delivery gas replenishment device is provided near the inlet of the first pressure gas source, and the delivery gas replenishment device is controlled according to the pressure of the delivery gas at the inlet of the first pressure gas source. A delivery gas venting device is provided near the outlet of the delivery gas demister, and the delivery gas venting device is controlled according to the flow rate and volume of the delivery gas at the outlet of the demister, while the delivery gas replenishment device is controlled according to the pressure of the delivery gas at the inlet of the first pressure gas source.

[0026] In an optional embodiment of the present invention, the first pressure gas source is a compressor.

[0027] Alternatively, the compressor may be a screw compressor, centrifugal compressor, or the like.

[0028] Furthermore, this application also provides an iron and steel smelting production line comprising: Vertical shaft furnace, wherein the vertical shaft furnace has a material outlet; An electric furnace, the electric furnace having a material inlet; and Continuous pneumatic conveying system for unsteady materials as described above; The material inlet of the conveying tank is connected to the material outlet of the vertical furnace, and the material outlet of the charging module is connected to the material inlet of the electric furnace.

[0029] The beneficial effects of this invention are as follows: The continuous pneumatic conveying system, control method, and steel smelting production line for unsteady materials proposed in this invention have the following advantages: In this invention, the unsteady material conveying device prioritizes maintaining the gas pressure in the conveying tank approximately equal to the gas pressure at the discharge port of the vertical furnace, thereby reducing the exchange between reducing gas and conveying gas in the vertical furnace and controlling the flow rate of the conveying gas within a reasonable range. This allows the flow rate of unsteady materials to remain stable during conveying, adapting to the smelting process characteristics of continuous production in the vertical furnace and intermittent charging in the electric furnace. It enables coupled and coordinated production of the vertical furnace and the electric furnace, improving production efficiency and reducing production energy consumption. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0031] In the attached diagram: Figure 1 This is a schematic flowchart of a continuous pneumatic conveying control method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a portion of a continuous pneumatic conveying system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of part two of a continuous pneumatic conveying system provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of part three of a continuous pneumatic conveying system provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of part four of a continuous pneumatic conveying system provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of part five of a continuous pneumatic conveying system provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the connection between the conveying tank and the hot delivery pipeline according to an embodiment of the present invention; Figure 8 This is a schematic diagram showing the connection between the intermediate tank and the loading tank in one embodiment of the present invention; Figure 9 This is a schematic diagram of the cross joint provided in one embodiment of the present invention.

[0032] The attached diagram is labeled as follows: 1. Vertical furnace; 2. Conveying tank; 3. Hot conveying pipeline; 4. Intermediate tank; 5. Charging tank; 6. Hot material silo; 7. Electric furnace; 8. Conveying gas dust removal device; 9. Pressure relief gas dust removal device; 10. Compressor; 11. Main conveying gas pipe; 12. Make-up gas pipeline; 13. Second pressure gas source; 14. Circulation pipeline; 15. Spray tower; 16. Water washing tower; 17. Cooling tower; 18. Demister; 19. Conveying gas replenishment device; 20. Return pipeline; 30. Cross joint; 31. Horizontal section; 32. Vertical section. Detailed Implementation

[0033] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0034] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the shape, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0035] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0036] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0037] With the continuous development of modern low-carbon metallurgical technology, large-scale smelting equipment such as vertical shaft furnaces have been widely used in industrial production. In these smelting processes, it is often necessary to continuously and in a closed manner transport unsteady materials such as high-temperature, high-density, and highly reactive hot-direct reduced iron (HDRI) from one process stage to the next downstream process stage (e.g., electric furnace 7). Continuous pneumatic conveying systems are key equipment for achieving long-distance, closed-loop transport of these materials. Their basic principle is to use high-speed flowing gas as a carrier to transport solid particulate materials from the material source to the target receiving equipment through a closed pipeline.

[0038] In actual conveying processes, due to the dynamic changes in the internal chemical reactions of the material source (such as a hydrogen-based shaft furnace) and the fluctuations in the state of direct reduced iron, the pressure and flow rate at the material source often exhibit irregular fluctuations, easily leading to instability in the pneumatic conveying system, such as pipe blockage and leakage of dust-containing gas. Existing pneumatic conveying technologies are mostly for conveying room-temperature, low-density, and chemically stable powder materials. The flow velocity of the conveying gas and powder material within the pipes is relatively low, and the mixture mainly exhibits fluid transport characteristics or powder transport characteristics. Technology for conveying high-temperature, high-density, large-particle-size, and unsteady-state materials such as hot direct reduced iron from shaft furnaces is scarce, and related equipment is also limited.

[0039] In view of this, please refer to Figures 1-9 This embodiment provides a continuous pneumatic conveying system for unsteady materials, a control method, and an iron and steel smelting production line. Figures 1-9 In the diagram, hollow dashed arrows indicate the direction of gas delivery, solid black arrows indicate the direction of HDRI particle delivery, and hollow solid arrows indicate the direction of delivery of the mixture of gas and HDRI particles.

[0040] Figures 2-6 In the diagram, terminals A1 and A2 are connected, B1 and B2 are connected, C1 and C2 are connected, D1 and D2 are connected, E1 and E2 are connected, and F1 and F2 are connected.

[0041] In this embodiment, the continuous pneumatic conveying system includes a conveying tank 2, a hot conveying pipeline 3, a charging module, and a first pressure gas source. The material inlet of the conveying tank 2 is connected to the material outlet of the vertical furnace 1. The material inlet of the hot conveying pipeline 3 is connected to the material outlet of the conveying tank 2. The charging module is used to load the material from the hot conveying pipeline 3 into the electric furnace 7, and the material outlet of the hot conveying pipeline 3 is connected to the material inlet of the charging module. The first pressure gas source is connected to the hot conveying pipeline 3 to supply conveying gas to the pipeline 3, and is also connected to the conveying tank 2 to adjust the pressure value of the conveying tank 2.

[0042] like Figure 1As shown in this embodiment, the control method for a continuous pneumatic conveying system for unsteady materials includes the following steps: S110: Obtain the pressure value at the material outlet of vertical furnace 1 and the pressure value inside the conveying tank 2; S120: Compare the pressure value of the material outlet of the vertical furnace 1 with the pressure value of the conveying tank 2 to obtain a first comparison result. If the first comparison result exceeds the first preset pressure threshold, adjust the output pressure of the first pressure gas source until the first comparison result meets the first preset pressure threshold.

[0043] In this embodiment, the non-steady-state material conveying device prioritizes maintaining the pressure of the conveying tank 2 approximately equal to the pressure at the discharge port of the vertical furnace 1, thereby reducing the exchange of reducing gas and conveying gas within the vertical furnace 1. Controlling the conveying gas flow rate within a reasonable range ensures that the flow rate of the non-steady-state material remains stable during conveying. This adapts to the smelting process characteristics of continuous production in the vertical furnace 1 and intermittent feeding in the electric furnace 7, achieving coupled and coordinated production of the vertical furnace 1 and the electric furnace 7, improving production efficiency, and reducing energy consumption.

[0044] In this embodiment, the first pressure gas source is a compressor 10. The outlet of the compressor 10 is connected to the heat delivery pipeline 3 via a pipeline 11 to supply delivery gas into the heat delivery pipeline 3. The first pressure gas source is connected to the delivery tank 2 via a connecting pipeline. A valve assembly is provided on the connecting pipeline. The opening and closing of the connecting pipeline is controlled by the valve assembly to regulate the pressure value of the delivery tank 2.

[0045] In this embodiment, the continuous pneumatic conveying system further includes a second pressure air source 13, which is connected to the conveying tank 2.

[0046] In step S120, the control method further includes the following steps: S121: Gas is supplied to the delivery tank 2 through the second pressure gas source 13 until the first comparison result meets the second preset pressure threshold. The first preset pressure threshold includes the second preset pressure threshold, and the range of the second preset pressure threshold is smaller than the range of the first preset pressure threshold.

[0047] In this embodiment, the second pressure gas source 13 is an external gas source independent of the first pressure gas source. This external gas source is connected to the delivery tank 2 via a pressure regulating pipe. A valve assembly is installed on the pressure regulating pipe, which can be used to regulate the pressure supplied to the delivery tank 2 by the second pressure gas source 13. Because the second pressure gas source 13 is independent of the first pressure gas source, it can independently regulate the pressure of the delivery tank 2 without being affected by the gas supply load of the first pressure gas source. This improves the efficiency and accuracy of pressure regulation in the delivery tank 2. It should be emphasized that the second pressure gas source 13 is not a mandatory option for continuous delivery.

[0048] In this embodiment, that is, before step S110, the following steps are also included: S100: Before the continuous pneumatic conveying system starts conveying, the pressure value of the conveying gas supplied by the first pressure gas source to the hot conveying pipeline is compared with the pressure value inside the conveying tank to obtain a second comparison result. If the second comparison result exceeds the fourth preset pressure threshold, the conveying tank 2 is pressurized by the first pressure gas source until the second comparison result meets the fourth preset pressure threshold. The first pressure gas source pressurizes the conveying tank 2 before the continuous pneumatic conveying system starts conveying, making the pressure of the conveying tank 2 closer to the pressure value of the material outlet of the vertical furnace 1, which is beneficial to ensure that the material discharged from the material outlet of the vertical furnace 1 can enter the conveying tank 2 more stably. The range of the fourth preset pressure threshold can be reasonably selected according to the actual operating conditions of the conveying tank 2.

[0049] In this embodiment, after comparing the pressure value at the material outlet of the vertical furnace 1 with the pressure value inside the conveying tank 2 to obtain the first comparison result, the following steps are also included: S130: If the first comparison result exceeds the third preset pressure threshold, the height of the material layer in the conveying tank 2 is adjusted until the first comparison result meets the third preset pressure threshold. The first preset pressure threshold includes the third preset pressure threshold, and the range of the second pressure threshold is smaller than the range of the first preset pressure threshold.

[0050] Specifically, in this embodiment, a flow regulating valve is installed at the material outlet of the conveying tank 2. The flow regulating valve adjusts the flow rate of HDRI particles discharged from the conveying tank 2, thereby controlling the HDRI material level within the conveying tank 2. This ensures that when there are slight fluctuations between the pressure at the material outlet of the vertical furnace 1 and the pressure within the conveying tank 2, the height of the material layer reduces gas flow resistance, minimizing the exchange of reducing gas in the vertical furnace 1 with the conveying gas in the conveying tank 2. Simultaneously, by controlling the flow rate of HDRI particles discharged from the conveying tank 2, the flow rate of HDRI particles discharged from the conveying tank 2 can be made approximately equal to the flow rate of material discharged from the vertical furnace 1, ensuring a continuous and stable conveying process for hot direct reduced iron in the vertical furnace. In this embodiment, the flow regulating valve at the material outlet of the conveying tank 2 is an electrically operated rotary valve. By adjusting the rotation speed of the electrically operated rotary valve, the flow rate of HDRI particles discharged from the conveying tank 2 can be precisely adjusted.

[0051] In this embodiment, the pressure difference between the pressure value at the material outlet of the vertical furnace 1 and the pressure value at the conveying tank 2 is ΔP, in Pa.

[0052] △P=|P 竖炉 -P 输送罐 |,△P∝g(Q 输送物料 -Q 物料 ), △P∝f(H 料位高度 ); Q 输送物料 =Q(r 转速 ); in, P 竖炉 This is the pressure value at the material outlet of vertical furnace 1, in Pa.

[0053] P 输送罐 This is the pressure value inside the conveying tank 2, in Pa.

[0054] H 料位高度 The height of the material level inside conveyor tank 2 is in meters (m).

[0055] r 转速 The speed of the rotary valve is expressed in r / min.

[0056] Q 输送物料 The discharge flow rate of the unsteady material discharged from conveying tank 2 is expressed in kg / h.

[0057] Q 物料 The discharge flow rate of unsteady material from the material outlet of vertical furnace 1 is expressed in kg / h.

[0058] In this embodiment, the unsteady material is HDRI particles.

[0059] f(H 料位高度 ) is △P with respect to H 料位高度 The function, g(Q) 输送物料 -Q 物料 ) is △P with respect to Q 输送物料 -Q 物料 The function, Q(r) 转速 ) for Q 输送物料 Regarding r 转速 The function.

[0060] In this embodiment, Q 输送物料 =Q(r 转速 That is, the discharge flow rate of HDRI particles from conveying tank 2 is a function of the rotational speed of the electric rotary valve. When Q 输送物料 =Q 物料 At that time, H 料位高度 If it remains constant, then ΔP also remains constant.

[0061] In this embodiment, the first preset pressure threshold includes the second preset pressure threshold, the second preset pressure threshold includes the third preset pressure threshold, the range of the third preset pressure threshold is smaller than the range of the second preset pressure threshold, and the range of the second preset pressure threshold is smaller than the range of the first preset pressure threshold. For example, the first preset pressure threshold is ±15 kPa, the second preset pressure threshold is ±10 kPa, and the third preset pressure threshold is ±5 kPa.

[0062] In this embodiment, step S120, that is, the step of adjusting the output pressure of the first pressure gas source, further includes the following steps: S122: Obtain the pressure loss value △P of the conveying gas from the outlet of the first pressure source 10 to the inlet of the hot delivery pipeline 3. 损失 .

[0063] S123: Based on the pressure value of the material outlet of the vertical furnace 1 and the pressure loss value △P of the conveying gas from the first pressure source 10 through pipeline 11 to the inlet of the hot conveying pipeline 3. 损失 Determine the output pressure of the first pressure gas source.

[0064] In this embodiment, the delivery gas is delivered from the outlet of the first pressure source 10 through the delivery gas main pipe 11 to the delivery gas inlet of the hot delivery pipeline 3.

[0065] Specifically, in this embodiment, the pressure value inside the conveying tank 2 is the same as the pressure value at the material outlet of the vertical furnace 1 as a priority control item. The output pressure of the compressor 10 used to provide the conveying gas is calculated as follows: P 输送罐 =P 竖炉 P 压缩机出口 =P 输送罐 +△P 损失； Among them, P 压缩机出口 The output pressure of compressor 10, ΔP 损失 The pressure loss value ΔP is the pressure at the inlet of the gas delivery pipeline 3 from the first pressure source 10 through the main gas delivery pipe 11 to the hot delivery pipeline 3. 损失 Compressor 10 can operate at a fixed frequency or a variable frequency.

[0066] In this embodiment, the continuous pneumatic conveying system further includes a return pipe 20 for conveying gas, which is connected to the outlet of the first pressure gas source and the inlet of the first pressure gas source.

[0067] In an optional embodiment of the present invention, after the conveying gas and unstable materials are separated in the intermediate tank, they are sent to the first pressure gas source for pressurization after dust removal, cooling and demisting, so as to be recycled.

[0068] Dust removal of conveyed gas can be achieved using either dry or wet methods.

[0069] In this embodiment, after the conveying gas and direct reduced iron are separated in the intermediate tank 4, a wet dust removal process is used. The conveying gas passes through water washing and cooling, washing and dust removal, cooling and dehumidification and other process units in sequence. After being pressurized by the compressor 10 through the conveying gas circulation pipeline 14, it is recycled.

[0070] Specifically, such as Figure 5 As shown, in this embodiment, after the conveying gas and direct reduced iron are separated in the intermediate tank 4, they are conveyed to the conveying gas dust removal device 8 for processing. The conveying gas dust removal device 8 includes a spray tower 15, a water washing tower 16, a cooling tower 17, and a demister 18. The conveying gas is processed sequentially through the spray tower 15, the water washing tower 16, the cooling tower 17, and the demister 18, and then enters the circulation pipeline 14.

[0071] In other embodiments, after the conveying gas and direct reduced iron are separated in intermediate tank 4, a dry dust removal process is used. The conveying gas passes through a bag filter to collect dust, is sprayed and vaporized in a spray tower to cool down, is cooled and liquefied by a demister to dehumidify, and is then sent to compressor 10 for pressurization and recycling.

[0072] The conveying gas, pressurized by compressor 10, can be conveyed to hot delivery pipeline 3 to convey hot direct reduced iron. In some embodiments, the conveying gas, pressurized by compressor 10, is conveyed to a heating furnace for heating before being conveyed to hot delivery pipeline 3 to increase the temperature of the conveying gas. In this embodiment, the conveying gas, pressurized by compressor 10, is directly conveyed to hot delivery pipeline 3.

[0073] In this embodiment, a gas supply device 19 (i.e., a gas source for supplying gas) and a gas release device are respectively provided on the gas circulation pipeline 14. The gas release device can be controlled according to the flow rate and flow rate of the gas at the inlet of the circulation pipeline 14 (i.e., the outlet of the demister 18 in this embodiment). The gas supply device 19 is controlled according to the pressure of the gas at the compressor inlet.

[0074] The control method for a continuous pneumatic conveying system further includes the following steps: S140: Obtain the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveying gas in the hot delivery pipeline 3. If the outlet flow rate of the first pressure gas source is greater than the theoretical flow rate of the conveying gas, and the difference between the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveying gas exceeds a preset flow difference threshold, then a portion of the flow rate from the outlet of the first pressure gas source is returned to the inlet of the first pressure gas source through the return pipeline 20 until the flow difference between the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveying gas meets the preset flow threshold. The range of the preset flow threshold can be reasonably selected according to the continuous pneumatic conveying system.

[0075] Among them, the theoretical flow rate of the conveying gas is negatively correlated with the solid-to-gas ratio set value of the hot conveying system and the standard volume density of the conveying gas, while the theoretical flow rate of the conveying gas is positively correlated with the discharge flow rate of the material outlet of the vertical furnace 1.

[0076] Specifically, the flow rate at the outlet of the first pressure gas source is also the outlet flow rate of the compressor 10, denoted as V. 压缩机出口The theoretical flow rate of the transported gas is expressed as V. 输送气理论流量 The relationship between the theoretical flow rate of the conveyed gas and the outlet flow rate of compressor 10 can be expressed as: V 压缩机出口 = (V 压缩机入口 -V 回流 )≈V 输送气理论流量 .

[0077] V 输送气理论流量 It can be calculated by setting a reasonable solid-gas ratio.

[0078] For example: V 输送气理论流量 = Q 物料 / (μ*ρ)

[0079] in, μ is the solid-to-gas ratio set value, either theoretical or empirical, in kg / kg; Q 物料 The discharge flow rate of unsteady material from the material outlet of vertical furnace 1 is expressed in kg / h. ρ is the standard bulk density of the transported gas, in kg / Nm³. 3 .

[0080] In this embodiment, the unsteady material is HDRI particles.

[0081] In this embodiment, the control method for the continuous pneumatic conveying system further includes the following steps: S150: Obtain the verification flow rate of the conveying gas, and adjust the actual flow rate of the conveying gas input from the first pressure gas source to the hot delivery pipeline 3 according to the verification flow rate of the conveying gas; Among them, the verification flow rate of the conveying gas is positively correlated with the energy conversion coefficient, the discharge flow rate of the material outlet of the vertical furnace 1, the specific heat capacity of the material in the hot conveying pipeline 3, and the temperature change value after the material in the hot conveying pipeline 3 is conveyed; the verification flow rate of the conveying gas is negatively correlated with the constant pressure heat capacity of the conveying gas, the temperature change value after the conveying gas in the hot conveying pipeline 3 is conveyed, and the standard state volume density of the conveying gas.

[0082] Specifically, the verification flow rate of the transported gas can be expressed as V. 校核 The unit is Nm 3 / h, then V 校核 =k*(Q 物料 *Cp 物料 *△T 物料 ) / (ρ*Cp 输送气 *△T 输送气 ) in, k is the energy conversion coefficient, which can be an empirical or theoretical value; Q物料 The discharge flow rate of unsteady material from the material outlet of vertical furnace 1 is expressed in kg / h. Cp 物料 Specific heat capacity of unsteady materials, expressed in J / kg K; Cp 输送气 This refers to the constant-pressure heat capacity of the transported gas, expressed in J / kg k. △T 物料 This represents the temperature change of the material in hot conveying pipeline 3 after the conveying process is completed, in kJ. △T 输送气 This represents the temperature change after the gas in the hot delivery pipeline 3 has been delivered, in kJ. ρ is the standard bulk density of the transported gas, in kg / Nm³. 3 .

[0083] In this embodiment, the hot delivery pipeline 3 is provided with a main inlet for conveying gas and a supplementary inlet for conveying gas. Along the conveying direction of the hot delivery pipeline 3, the main inlet for conveying gas is close to the material inlet of the hot delivery pipeline 3, while the supplementary inlet for conveying gas is farther away from the material inlet of the hot delivery pipeline 3 compared to the main inlet for conveying gas. A first pressure gas source is connected to both the main inlet for conveying gas and the supplementary inlet for conveying gas. In this embodiment, the first pressure gas source is connected to the main inlet for conveying gas of the hot delivery pipeline 3 via a main conveying gas pipe 11, and the first pressure gas source is connected to the supplementary inlet for conveying gas of the hot delivery pipeline 3 via a supplementary gas pipe 12. There can be multiple supplementary inlets for conveying gas, and multiple main inlets for conveying gas are sequentially arranged along the conveying direction of the hot delivery pipeline 3.

[0084] In this embodiment, the control method for the continuous pneumatic conveying system further includes the following steps: S160: Determine the pressure difference between the pressure value of the main inlet of the conveying gas and the pressure value of the supplementary inlet of the conveying gas, and adjust the proportion of the conveying gas flow rate of the first pressure gas source input to the main inlet of the conveying gas and the supplementary inlet of the conveying gas according to the pressure difference.

[0085] Among them, the flow rate of the conveying gas at the inlet of the first pressure gas source is positively correlated with the pressure difference of the conveying gas.

[0086] Specifically, such as Figure 9 As shown, in this embodiment, along the conveying direction of the hot delivery pipeline 3, the hot delivery pipeline 3 includes a straight section 31 and a vertical section 32 connected in sequence. The vertical section 32 is vertically upward, the gas supply inlet is located at the bottom of the vertical section 32, and the main gas inlet is located at the beginning of the straight section 31.

[0087] In this embodiment, the straight section 31 and the vertical section 32 are connected to each other by a cross joint 30. The cross joint 30 includes a horizontal portion and a vertical portion. One end of the horizontal portion is connected to the straight section 31, and one end of the vertical portion is connected to the vertical section 32. The gas supply inlet is located at the other end of the vertical portion.

[0088] In this example, the conveying pressure of the hot delivery pipeline 3 is determined by the pressure value of the material outlet of the vertical furnace 1, and the conveying flow rate of the hot delivery pipeline 3 is mainly determined by the mass flow rate of the conveyed HDRI particles. During the conveying process of the hot delivery pipeline 3, conveying gas is supplemented at the bottom of the vertical section 32 of the hot delivery pipeline 3, that is, at the cross joint 30 between the horizontal section 31 and the vertical section 32, a conveying gas supplementation inlet is set at the bottom of the vertical section 32. In this embodiment, the outlet of the compressor 10 is connected to the main inlet of the conveying gas of the hot delivery pipeline 3 through the main conveying gas pipe 11, and the compressor 10 is connected to the conveying gas supplementation inlet of the hot delivery pipeline 3 through the supplementary gas pipe 12. A regulating valve group can be installed on the supplementary gas pipe 12 to control the flow rate of the conveying gas in the supplementary gas pipe 12, so as to regulate the conveying loss pressure value of the hot delivery pipeline 3, thereby realizing the regulation of the intermediate tank pressure.

[0089] The supplemented delivery gas can adjust the local flow field at the cross joint 30, regulate the resistance loss of the horizontal section 31, increase the gas flow velocity in the vertical section 32, increase the delivery gas pressure at the end of the hot delivery pipeline 3, and push the delivery gas to return to the compressor 10 quickly to accelerate the circulation.

[0090] The flow rate of the conveying gas at the first pressure gas source input inlet is expressed as V. 补充气 The unit is Nm 3 / h, then V 补充气 Let I(△P) be a function of △P. I(△P) can be expressed as: V 补充气 =I(△P) =ε*V 压缩机出口 ; (V 补充气 +V 热送管道入口 ) = V 压缩机出口 = (V 压缩机入口 -V 回流 )≈V 输送气理论流量 .

[0091] in, ε is the supplementary gas ratio coefficient, with a value ranging from 0 to 1; △P is the difference between the pressure at the main inlet of the conveying gas and the pressure at the supplementary inlet of the conveying gas, in Pa. 热送管道入口 The actual flow rate of gas delivered at the inlet of hot delivery pipeline 3.

[0092] like Figures 2-6 as well as Figure 8As shown, in this embodiment, the loading module includes an intermediate tank 4, a loading tank 5, and a hot material bin 6 connected sequentially along the material conveying direction. The hot delivery pipe 3 is connected to the intermediate tank 4. The intermediate tank 4 is used to separate materials and convey gas. The loading tank 5 is used to depressurize the materials. The hot material bin 6 is used to temporarily store the depressurized materials and load the depressurized materials into the electric furnace 7.

[0093] HDRI particles are transported through hot delivery pipe 3 to intermediate tank 4 located above hot material bin 6 of electric furnace 7. After entering intermediate tank 4, HDRI particles are deposited at the bottom of intermediate tank 4, while delivery gas is discharged from the top of intermediate tank 4, achieving gas-solid separation. Delivery gas is then sent to delivery gas dust removal device 8 and cooling device for treatment. After dust removal and cooling, delivery gas is returned to compressor 10 through circulation pipe 14 for recycling.

[0094] A loading tank 5 is connected below the intermediate tank 4. The loading tank 5 is equipped with a pressure equalization device, a pressure relief device, and a purification and cooling device for the discharged gas. After HDRI particles have settled to a certain level in the intermediate tank 4, the loading tank 5 is pressurized to the same pressure as the intermediate tank 4 (i.e., pressure equalization). The connecting valve between the intermediate tank 4 and the loading tank 5 is opened, and the high-pressure HDRI particles are loaded into the loading tank 5. The connecting valve between the intermediate tank 4 and the loading tank 5 is closed, and the staged pressure relief valve group (i.e., pressure relief device) of the loading tank 5 is opened to depressurize the loading tank 5 and the HDRI particles inside to near atmospheric pressure. The depressurized gas generated during depressurization is treated by the depressurized gas dust removal device 9, etc., and can be recycled or discharged into the atmosphere after harmless treatment. In this embodiment, the depressurized gas dust removal device 9 includes a spray tower 15 and a water washing tower 16. In this embodiment, the continuous pneumatic conveying system includes an intermediate tank 4 and a loading tank 5, which respectively achieve gas-solid separation of HDRI particles and conversion from high pressure to near-atmospheric pressure, thus stabilizing the end pressure of the hot conveying pipeline 3 and ensuring that loading does not affect the stability of the conveying process. Simultaneously, it matches the near-atmospheric pressure and intermittent loading process characteristics of the electric furnace 7.

[0095] like Figures 2-9 As shown, in this embodiment, the continuous pneumatic conveying system for unsteady materials is used to implement the control method described above. The continuous pneumatic conveying system includes a conveying tank 2, a hot conveying pipeline 3, a loading module, and a first pressure gas source. The material inlet of the conveying tank 2 is connected to the material outlet of the vertical furnace 1, the material inlet of the hot conveying pipeline 3 is connected to the material outlet of the conveying tank 2, the loading module is used to load the material from the hot conveying pipeline 3 into the electric furnace 7, and the material outlet of the hot conveying pipeline 3 is connected to the material inlet of the loading module. The first pressure gas source is connected to the hot conveying pipeline 3 to supply conveying gas to the hot conveying pipeline 3, and the first pressure gas source is also connected to the conveying tank 2 to adjust the pressure value of the conveying tank 2.

[0096] In this embodiment, the HDRI particles, cooled to atmospheric pressure after being processed by the charging tank 5, are loaded into the hot material silo 6 through the outlet valve group and the distribution valve. The hot material silo 6 is typically configured with 1 to 4 units depending on the operating characteristics of the electric furnace 7. The hot material silo 6 is equipped with an inert gas atmosphere protection device, a weighing device, a venting device, etc. A flow control valve and charging pipe are installed at the bottom of the hot material silo 6. HDRI particles are added to the electric furnace 7 according to the smelting process of the electric furnace 7.

[0097] In this embodiment, the pressure and flow rate of the conveying gas are the core control elements to ensure the stable completion of the conveying target by the continuous pneumatic conveying system. In the continuous pneumatic conveying system, one end of the hot conveying pipeline 3 is directly connected to the vertical furnace 1 through a discharge three-way valve, a discharge pipe, a conveying tank 2, and another hot conveying pipeline 3. The other end of the hot conveying pipeline 3 is connected to the electric furnace 7 through an intermediate tank 4, a charging tank 5, a three-way valve, and a hot material bin 6. HDRI particles fall into the conveying tank 2 and the hot conveying pipeline 3 by gravity. Under the action of pneumatic force, they are transported along the hot conveying pipeline 3 to the intermediate tank 4. In the intermediate tank 4, the conveying gas and HDRI particles are separated. After pressure equalization and depressurization steps, the HDRI particles fall into the charging tank 5 and the hot material bin 6 by gravity, and finally enter the electric furnace 7. The continuous pneumatic conveying system prioritizes maintaining the gas pressure in conveying tank 2 approximately equal to the gas pressure at the material outlet of vertical furnace 1. This reduces the exchange between reducing gas and conveying gas within vertical furnace 1 and keeps the flow rate of conveying gas in hot conveying pipeline 3 within a reasonable range, ensuring stable conveying flow of HDRI particles. The theoretical conveying flow rate is calculated using a solid-to-gas ratio setpoint, and the flow rate is adjusted based on HDRI particle temperature drop feedback. The position and flow rate of the conveying gas injected into hot conveying pipeline 3 are appropriately allocated. At the end of the continuous pneumatic conveying system, intermediate tank 4, charging tank 5, and hot material bin 6 are installed, supplemented by pressure equalization and pressure relief devices. This achieves stable gas-solid separation of HDRI particles, conversion from high pressure to atmospheric pressure, and transition from continuous conveying to intermittent loading into hot material bin 6. This effectively reduces resistance loss during conveying, minimizes HDRI particle temperature drop and pulverization during conveying, and stabilizes the conveying process. After completing its conveying task, the conveying gas undergoes gas-solid separation in intermediate tank 4, and after dust removal, cooling, and demisting processes, it is sent to compressor 10 for pressurization and recycling.

[0098] In this embodiment, the steel smelting production line includes a vertical shaft furnace 1, an electric arc furnace 7, and a continuous pneumatic conveying system for unsteady materials as described above. The vertical shaft furnace 1 has a material outlet, and the electric arc furnace 7 has a material inlet. The material inlet of the conveying tank 2 is connected to the material outlet of the vertical shaft furnace 1, and the material outlet of the charging module is connected to the material inlet of the electric arc furnace 7.

[0099] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can 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 those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A control method for a continuous pneumatic conveying system for unsteady-state materials, characterized in that, The continuous pneumatic conveying system includes: A conveying tank, wherein the material inlet of the conveying tank is connected to the material outlet of the vertical furnace; A hot delivery pipeline, wherein the material inlet of the hot delivery pipeline is connected to the material outlet of the conveying tank; A charging module, used to load material from the hot conveying pipe into the electric furnace, wherein the material outlet of the hot conveying pipe is connected to the material inlet of the charging module; and A first pressure gas source is connected to the heat delivery pipeline to supply delivery gas to the heat delivery pipeline. The first pressure gas source is also connected to the delivery tank to adjust the pressure value inside the delivery tank. The control method includes: Obtain the pressure value at the material outlet of the vertical furnace and the pressure value inside the conveying tank; The pressure value at the material outlet of the vertical furnace is compared with the pressure value inside the conveying tank to obtain a first comparison result. If the first comparison result exceeds a first preset pressure threshold, the output pressure of the first pressure gas source is adjusted until the first comparison result meets the first preset pressure threshold.

2. The control method for the continuous pneumatic conveying system for unsteady materials according to claim 1, characterized in that, The continuous pneumatic conveying system further includes a second pressure gas source, which is connected to the conveying tank. The control method further includes: Gas is also supplied to the delivery tank through the second pressure gas source until the first comparison result meets the second preset pressure threshold. The first preset pressure threshold includes the second preset pressure threshold, and the range of the second preset pressure threshold is smaller than the range of the first preset pressure threshold.

3. The control method for the continuous pneumatic conveying system for unsteady materials according to claim 1, characterized in that, After comparing the pressure value at the material outlet of the vertical shaft furnace with the pressure value inside the conveying tank to obtain the first comparison result, the method further includes: If the first comparison result exceeds the third preset pressure threshold, the height of the material layer in the conveying tank is adjusted until the first comparison result meets the third preset pressure threshold. The first preset pressure threshold includes the third preset pressure threshold, and the range of the third preset pressure threshold is smaller than the range of the first preset pressure threshold.

4. The control method for a continuous pneumatic conveying system for unsteady materials according to claim 1, characterized in that, Before the continuous pneumatic conveying system starts conveying, the pressure value of the conveying gas supplied by the first pressure gas source to the hot conveying pipeline is compared with the pressure value in the conveying tank to obtain a second comparison result. If the second comparison result exceeds the fourth preset pressure threshold, the conveying tank is pressurized by the first pressure gas source until the second comparison result meets the fourth preset pressure threshold.

5. The control method for a continuous pneumatic conveying system for unsteady materials according to claim 1, characterized in that, Adjusting the output pressure of the first pressure gas source includes: Obtain the pressure loss value from the outlet of the first pressure gas source to the inlet of the hot delivery pipeline; The output pressure of the first pressure gas source is determined based on the pressure value of the material outlet of the vertical furnace and the pressure loss value from the first pressure gas source to the gas inlet of the hot delivery pipeline.

6. The control method for a continuous pneumatic conveying system for unsteady materials according to any one of claims 1 to 5, characterized in that, The continuous pneumatic conveying system also includes a conveying gas return pipe, which connects the outlet of the first pressure gas source and the inlet of the first pressure gas source. The control method further includes: Obtain the outlet flow rate of the first pressure gas source and the theoretical flow rate of the transport gas in the heat delivery pipeline; If the outlet flow rate of the first pressure gas source is greater than the theoretical flow rate of the conveyed gas, and the difference between the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveyed gas exceeds a preset flow difference threshold, then a portion of the outlet flow rate of the first pressure gas source is returned to the inlet of the first pressure gas source through the return pipe until the flow difference between the outlet flow rate of the first pressure gas source and the theoretical flow rate of the conveyed gas meets the preset flow threshold. The theoretical flow rate of the conveying gas is negatively correlated with the solid-to-gas ratio setting of the pneumatic conveying system and the standard volume density of the conveying gas, and positively correlated with the discharge flow rate of the material outlet of the vertical furnace.

7. The control method for a continuous pneumatic conveying system for unsteady materials according to any one of claims 1 to 5, characterized in that, The control method further includes: Obtain the verification flow rate of the delivery gas, and adjust the actual flow rate of the delivery gas input from the first pressure gas source to the hot delivery pipeline according to the verification flow rate of the delivery gas; The verification flow rate of the conveying gas is positively correlated with the energy conversion coefficient, the discharge flow rate of the material outlet of the vertical furnace, the specific heat capacity of the material in the hot conveying pipeline, and the temperature change value after the material in the hot conveying pipeline is conveyed. The verification flow rate of the conveying gas is negatively correlated with the constant pressure heat capacity of the conveying gas, the temperature change value after the conveying gas in the hot conveying pipeline is conveyed, and the standard volume density of the conveying gas.

8. The control method for a continuous pneumatic conveying system for unsteady materials according to claim 7, characterized in that, The delivery gas check flow is expressed as V 校核 then V 校核 =k*(Q 物料 *Cp 物料 *△T 物料 ) / (ρ*Cp 输送气 *△T 输送气 ) in, k is the energy conversion coefficient; Q 物料 The discharge flow rate of the unsteady material discharged from the material outlet of the vertical furnace; Cp 物料 The specific heat capacity of the unsteady material; Cp 输送气 The constant-pressure heat capacity of the transported gas; △T 物料 The temperature change value after the material is transported in the hot delivery pipeline is completed; △T 输送气 The value representing the temperature change after the gas in the hot delivery pipeline has been delivered. ρ is the standard bulk density of the transported gas, in kg / Nm³. 3 .

9. The control method for a continuous pneumatic conveying system for unsteady materials according to any one of claims 1 to 5, characterized in that, The hot delivery pipeline is provided with a main inlet for conveying gas and a supplementary inlet for conveying gas. Along the conveying direction of the hot delivery pipeline, the main inlet for conveying gas is close to the material inlet of the hot delivery pipeline, and the supplementary inlet for conveying gas is far away from the material inlet of the hot delivery pipeline. The first pressure gas source is connected to the main inlet for conveying gas and the supplementary inlet for conveying gas respectively. The control method further includes: Determine the pressure difference between the pressure value at the main inlet of the conveying gas and the pressure value at the supplementary inlet of the conveying gas; The flow rate ratio of the first pressure gas source inputting into the main inlet and the supplementary inlet of the conveying gas is adjusted according to the pressure difference of the conveying gas. The flow rate of the conveying gas input to the conveying gas replenishment inlet of the first pressure gas source is positively correlated with the pressure difference of the conveying gas.

10. The control method for a continuous pneumatic conveying system for unsteady materials according to claim 9, characterized in that, The pressure difference between the material outlet pressure of the vertical shaft furnace and the pressure of the conveying tank is ΔP, where ΔP = |P| 竖炉 -P 输送罐 |,△P∝g(Q 输送物料 -Q 物料 ), △P∝f(H 料位高度 ), Q 输送物料 =Q(r 转速 ); in, P 竖炉 The pressure value at the material outlet of the vertical shaft furnace; P 输送罐 The pressure value inside the delivery tank; H 料位高度 The material level height inside the conveying tank; r 转速 The rotational speed of the conveying rotary valve at the material outlet of the conveying tank; Q 输送物料 The discharge flow rate of the unsteady material discharged from the conveying tank; Q 物料 The discharge flow rate of the unsteady material discharged from the material outlet of the vertical furnace.

11. The control method for a continuous pneumatic conveying system for unsteady materials according to claim 9, characterized in that, Along the conveying direction of the hot delivery pipeline, the hot delivery pipeline includes a straight section and a vertical section connected in sequence. The vertical section is vertically upward, the gas supply inlet is located at the bottom of the vertical section, and the main gas inlet is located at the beginning of the straight section.

12. The control method for a continuous pneumatic conveying system for unsteady materials according to any one of claims 1 to 5, characterized in that, The loading module includes an intermediate tank, a loading tank, and a hot material silo connected sequentially along the material flow direction. The hot delivery pipeline is connected to the inlet of the intermediate tank. The intermediate tank is used to separate materials and convey gas. The loading tank is used to depressurize the materials. The hot material silo is used to load the depressurized materials into the electric furnace.

13. A continuous pneumatic conveying system for unsteady-state materials, characterized in that, For implementing the control method as described in any one of claims 1 to 12, the continuous pneumatic conveying system comprises: A conveying tank, wherein the material inlet of the conveying tank is connected to the material outlet of the vertical furnace; A hot delivery pipeline, wherein the material inlet of the hot delivery pipeline is connected to the material outlet of the conveying tank; A charging module, used to load material from the hot conveying pipe into the electric furnace, wherein the material outlet of the hot conveying pipe is connected to the material inlet of the charging module; and A first pressure gas source is connected to the hot delivery pipeline to supply delivery gas to the hot delivery pipeline. The first pressure gas source is also connected to the delivery tank to adjust the pressure value of the delivery tank. The control method includes: Obtain the pressure value at the material outlet of the vertical furnace and the pressure value inside the conveying tank; The pressure value at the material outlet of the vertical furnace is compared with the pressure value inside the conveying tank to obtain a first comparison result. If the first comparison result exceeds a first preset pressure threshold, the output pressure of the first pressure gas source is adjusted until the first comparison result meets the first preset pressure threshold.

14. A steel smelting production line, characterized in that, include: Vertical shaft furnace, wherein the vertical shaft furnace has a material outlet; An electric furnace having a material inlet; as well as The continuous pneumatic conveying system for unsteady materials as described in claim 13; The material inlet of the conveying tank is connected to the material outlet of the vertical furnace, and the material outlet of the charging module is connected to the material inlet of the electric furnace.

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