# Application of Waste Tire Carbon for Iron-Containing Dust Reduction in Industrial Processes
## 1 Introduction  
IBD is a solid waste generated during the steel production process. It is produced by collecting particulate emissions from exhaust gases through dry dust collectors. Depending on the point of origin, it can be classified into various types, such as feedstock dust, hot gravity dust, and furnace dust [1]. The TFe content in it is relatively high, ranging from 30% to 70%. Additionally, the production yield is significant, accounting for approximately 10% of crude steel output [2]. Based on China's crude steel production of 1.029 billion tons in 2023, the annual generation of IBD exceeds 100 million tons, with an estimated recoverable iron content of 30 to 70 million tons. This represents economic benefits worth billions. Besides its high TFe content, IBD also contains hazardous elements such as Cr and Pb, typically present in the form of oxides or sulfides. If not treated promptly, the large-scale accumulation of it poses significant environmental risks, including occupying valuable space, generating fugitive dust, and causing the leaching of harmful elements, all of which can result in severe environmental pollution. The treatment of IBD aims primarily at removing harmful elements and extracting valuable metals. The treatment methods can be divided into three types: physical methods, hydrometallurgical methods, and pyrometallurgical methods. Physical methods use magnetic separation or mechanical separation to sort different elements such as Fe, Zn, and C [3]. However, the treatment efficiency is relatively low [4]. Hydrometallurgical methods mainly target dust with a high Zn content, using acidic or alkaline leaching agents to extract Zn, with a relatively low utilization efficiency for Fe [2]. Pyrometallurgical methodsinvolve directly processing the raw material or pelletizing it before placing it in furnaces such as blast furnaces, converters, or rotary kilns. Under high temperature and the action of reducing agents, valuable elements are reduced. This method is widely used due to its broad applicability to raw materials and high metal recovery rates [2]. In pyrometallurgical reduction, reaction temperature and duration are the most critical factors influencing metal recovery efficiency. Experimental results vary widely across studies. For example, [PERSON] et al. achieved an Mn reduction rate of 96.8% using corn straw to reduce soft manganese ore at 600 \({}^{\circ}\)C for 90 min [5]. [PERSON], [PERSON] et al. reached 95.26% Fe reduction using hydrogen on high-purity iron concentrate at 575 \({}^{\circ}\)C for 60 min [6], with both demonstrating high efficiency at relatively low temperatures. In contrast, [PERSON] et al. recovered 86% Cu from copper slag using rubber seed oil at 1350 \({}^{\circ}\)C within 4 min, indicating high efficiency at high temperature over a short duration [7]. [PERSON] et al. studied the temperature characteristics of hydrogen and the carbon reduction of iron oxide with three biomass types, identifying 806-822 K as the characteristic temperature for gas-based reduction and 1116-1132 K for carbon reduction [8]. In the selection of furnace types, the blast furnace has a relatively higher furnace start-up rate in domestic enterprises, at 73.44%, and does not require the pelletizing step for charging materials as in the case of the converter [9]. There has been extensive research on the reduction of IBD in blast furnaces. Researchers typically use vertical furnaces to simulate blast furnaces and study the effects of reduction temperature, time, types of reducing agents, and their mixing ratios on the iron reduction rate. However, air or oxygen is injected into blast furnaces to maintain temperature, with the oxygen content ranging from 21% (air) to 100% (pure oxygen), though the average O\({}_{2}\) level inside the furnace remains below 10%. Increasing O\({}_{2}\) content enhances fuel utilization.