Technical Characteristics, Usage Maintenance, and Fault Analysis of Blast Furnace Pulverized Coal Lance

The blast furnace pulverized coal lance is the core equipment for implementing the coal injection process in blast furnaces. Its performance and stability directly determine the coal injection volume, pulverized coal combustion efficiency, and the continuity of blast furnace production. This article will provide a detailed explanation from aspects such as process characteristics, product types, usage maintenance, and fault analysis.

I. Core Value of the Pulverized Coal Lance

In the blast furnace ironmaking process, stabilizing and increasing the coal injection volume is a key approach to reducing the coke ratio, saving energy, and controlling production costs. A high-quality pulverized coal lance not only extends its own service life but also supports the advanced ironmaking process of "high blast temperature, oxygen enrichment, and large injection volume" by protecting the tuyere and reducing unplanned blast furnace downtime.

II. Process Characteristics and Usage Features of the Pulverized Coal Lance

(I) 2520 Heat-Resistant Steel Ceramic-Lined Lance (Mainstream High-Performance Model)

This type of lance is designed for the harsh conditions of high temperature and high wear in blast furnaces and is currently a widely used high-performance lance. Its core advantages are reflected in material and structural innovations:

1. Process Characteristics

• Main Material: The lance body is made of 2520 heat-resistant steel (i.e., 06Cr25Ni20 austenitic stainless steel), which offers excellent high-temperature oxidation resistance (capable of withstanding temperatures above 800°C for extended periods) and corrosion resistance, making it suitable for the high-temperature environment inside the blast furnace tuyere.
• Wear Resistance Enhancement: The process of "locally lining the inner wall of the steel pipe with ceramics" is adopted. Alumina or silicon carbide ceramics are lined in the lance tip and front section areas where pulverized coal erosion is most severe, improving wear resistance by 3-5 times and significantly extending the overall service life of the lance.
• 
  

2. Usage Features

• Low Replacement Rate: The composite structure of heat-resistant steel and ceramic lining significantly reduces the risk of wear and burn-through, minimizing downtime caused by frequent replacements and reducing the labor intensity of disassembly and installation for workers.
• High Production Stability: The lance body has high strength and minimal deformation, enabling it to maintain a stable lance position and coal injection angle over the long term. This avoids uneven injection caused by lance bending, reduces blast furnace downtime, and improves production efficiency.
• 
  
• Supports Large Injection Volume: The stable structure and wear resistance allow it to meet the requirements of high coal ratio injection, providing equipment support for blast furnaces to achieve "coal replacing coke," directly reducing ironmaking costs.
• Repairability: For minor damage in non-core areas, repairs can be made through methods such as local patch welding or ceramic repair, further extending the overall service life and reducing equipment investment costs.