A Chinese research team has reportedly developed a new iron production technology that can reduce iron ore in seconds instead of hours with almost no impact on the climate. The innovation works without coal and can also handle low-quality raw materials. The ‘explosive’ ironmaking breakthrough achieves 3,600-fold productivity boost. After more than a decade of intensive research in China, a new ironmaking technology is poised to revolutionise the global steel manufacturing industry, reports the South China Morning Post, Hong Kong's premier English language newspaper.
The method involves injecting finely ground iron ore powder into an extremely hot furnace, triggering an "explosive chemical reaction", according to the engineers involved in the project. The result is a display of bright red, glowing liquid iron droplets that rain down and collect at the bottom of the furnace, forming a stream of high-purity iron that can be directly used for casting or "one-step steelmaking".
Flash ironmaking: Iron production in three to six seconds Known as flash ironmaking, the method "can complete the ironmaking process in just three to six seconds, compared to the five to six hours required by traditional blast furnaces", wrote the project team led by Professor Zhang Wenhai, an academician of the prestigious Chinese Academy of Engineering, in a paper published in the peer-reviewed journal Nonferrous Metals in November. This equates to a 3,600-fold or more increase in the speed of ironmaking. The new method also works exceptionally well for low or medium-yield ores that are abundant in China, according to the researchers. Existing iron production methods depend heavily on high-yield ores, and China spends a huge amount of money importing these ores from Australia, Brazil and Africa.
The goal of near-zero carbon dioxide emissions According to calculations by Zhang and his colleagues, the new technology could improve the energy use efficiency of China's steel industry by more than one-third. As it eliminates the need for coal entirely, it would also enable the steel industry to achieve the coveted goal of "near-zero carbon dioxide emissions", Zhang's team added. One of the most daunting technical challenges in bringing flash ironmaking to life is the ore-spraying lance. Iron ore must be dispersed in a high-temperature, high-reducibility tower space with a large specific surface area to trigger the explosion. Zhang's team has developed a vortex lance with exceptional uniform distribution performance, capable of injecting 450 tonnes of iron ore particles per hour. A reactor equipped with three such lances can produce an impressive 7.11 million tonnes of iron annually. According to the paper, the lance "has already entered commercial production".
Flash smelting technology for copper production Zhang's journey with flash smelting technology began in the 1970s when he applied it to large-scale copper production. Today, China's consumption of copper accounts for nearly 60 per cent of global production, a testament to Zhang's enduring impact on the industry. While the idea of applying this process to ironmaking originated in the United States, it was Zhang's team who invented a flash smelting technology capable of directly producing liquid iron. They obtained a patent in 2013 and spent the next decade refining the method. "The completed laboratory and pilot tests have proven the feasibility of the process," Zhang wrote. According to government statistics, the success rate for new technologies that have undergone pilot tests exceeds 80 per cent in China.
Source: South China Morning Post
