injection tank
1. According to the layout form of the injection tank, it can be divided into parallel injection and serial tank injection. The sequential or cross switching of the tanks is used to ensure the uninterrupted pulverized coal injection into the blast furnace. For easy handling of injection accidents, the number of parallel tanks is usually 3. If sequential tank switching is adopted for parallel injection, it will have a certain impact on the stability of injection. However, cross tank switching can improve the stability of injection, but the latter must be equipped with precise measurement and control means. In addition, parallel injection covers a large area, but the injection weighing is simple, and the investment is smaller than that of the overlapping type. Therefore, it is often used in the direct injection process system of small blast furnaces.
2. According to the injection method, it can be divided into direct injection and indirect injection.
The direct injection method sets the injection tank under the coal bunker of the pulverizing system, and directly injects pulverized coal into the blast furnace tuyere, eliminating the need for an injection station near the blast furnace. It is characterized by saving the investment in the injection station and corresponding operation and maintenance costs. This method is more commonly used in small and medium-sized blast furnaces. Indirect injection, on the other hand, transports the prepared pulverized coal to an injection station near the blast furnace via a dedicated coal pipeline or tank truck, and then the injection station injects the pulverized coal into the blast furnace. It is characterized by a larger investment and complex equipment configuration. In addition to the injection tank group, it must also be equipped with corresponding powder recovery and dust removal devices.
The injection tank (pulverized coal injection tank) is generally composed of the following parts: elliptical or dished heads, circular straight sections, conical lower heads, supports, and manholes. It is a typical internal pressure vessel. According to the specifications, the design pressure only needs to be greater than the high working pressure, but for safety considerations, especially when injecting bituminous coal, its design pressure should be appropriately increased.
The injection system consists of different types of injection tank groups, corresponding bell valves, fluidization devices, etc. Pulverized coal injection usually involves filling the injection tank group with compressed air, and then introducing secondary compressed air from the mixer to inject the pulverized coal into the blast furnace tuyere through pipelines and injection pipes. The injection tank group can adopt parallel layout, with coal charging and coal injection alternating; it can also adopt overlapping layout, where the bottom tank is only used as an injection tank, and coal charging is completed through the upper tank and its pressure equalization and discharge device.
Principle and Application of Pulverized Coal Injection Tank
The pulverized coal injection tank is a traditional combustion device. Its main principle is to inject pulverized coal into the combustion chamber through a nozzle, mix it with air and burn to generate high-temperature and high-pressure gas, thereby providing heat for industrial production or civil life and other fields. Pulverized coal injection tanks are widely used in various industrial sectors, such as coal mining, cement, chemical, metallurgical and other industries, providing necessary energy support for production.
| Chemicals/Conveying Equipment/Fans | |
