In the last article, we compared the advantages and disadvantages of several coal-based reduction processes, and concluded that the rotary hearth furnace process is more suitable. This article will introduce the development of rotary hearth furnace process and the INMETCO method in rotary hearth furnace process.

At present, there are mainly the following technical routes for direct reduced iron. Coal-based direct reduced iron and gas-based direct reduced iron,Among them, gas-based reduction technologies include: COREX, Midrex, FINEX, HIsmelt, etc.Among them, coal-based reduction technologies include: tunnel kiln, RHF, rotary kiln, etc. Gas-based reduction technology can achieve large-volume industrial production. The comprehensive economic indicators are good, but the investment is relatively large. Coal-based reduction technology generally has low output and relatively low investment.

Non-blast furnace iron making technology has grown significantly in recent years, driven by increasing environmental requirements, the need for high-quality steel materials, and especially the Chinese government's commitment to "carbon neutrality" to the world. Non-blast furnace iron-making technology is dominated by the gas-based shaft furnace process, because the gas-based shaft furnace can use hydrogen reduction technology, which greatly reduces carbon emissions, In addition to the gas - based shaft furnace process, rotary kiln, tunnel kiln, RHF and other technologies are also used.

To further enhance DRI for steelmaking, it can be converted to pig iron or hot metal via melting. There are existing processes in the industry that use electric energy in furnaces such as submerged arc furnaces to convert DRI into hot metal. Air Products’ novel DRI melting process uses oxy-fuel combustion in place of electric power to accomplish this melting. Figure 4 provides a process diagram (patent pending) .

Advantages of charging DRI hot coming out of the shaft reactor have been well documented, namely productivity increase and decrease in power use. Few DRI plants in the world have the ideal setup with an EAF downstream of the DRI plant, where the DRI coming out of the shaft furnace can be charged hot into the EAF.

Direct Reduced Iron (DRI) is the second most viable source of virgin iron used in steelmaking after pig iron or hot metal produced in blast furnaces. DRI is produced by direct reduction of iron ore using carbon monoxide and hydrogen. Natural gas-based shaft reactors are commonly used in North and South America for DRI production while coal-based DRI is common in Asian markets. Inexpensive supply of natural gas in the United States makes DRI an attractive source of iron for steelmakers.

In the use of high-pressure briquetting machine and other briquetting equipment, we often encountered the motor heating, even burnt failure. What are the main causes of these failures and how to maintain them? Luoyang Kaizheng's engineers will analyze for you that how to make your briquetting equipment have a longer service life, lower failure rate, and more economic benefits.

In the production of float glass​, the mixing process is a very important link in the production of the mixture, and the mixer is also a very important key piece of equipment. The correct selection and use of the mixer is the basis for improving the quality of the mixture and ensuring the stable quality of the glass.

Since the tailings are very fine in size, it is more reasonable for the raw tailings to be pelletized followed by direct reduction roasting. In order to investigate the possibility of iron recovery by direct reduction roasting of carbon briquette from high iron tailings, the effects of different binders on the green briquette strength and high temperature strength of carbon briquette from high iron tailings were studied.

Given the current problem of limestone solid waste treatment in steel mills, two briquetting treatment techniques and methods are introduced. It is suitable for the recycling of limestone mud cake in steel mills to realize the recycling of dust and sludge generated in its production process.