In recent years, with the implementation of a series of new environmental protection policies, higher requirements have been placed on the environmental management methods of foundry companies and the occupational health and safety of employees. The pollution control technology and facilities of foundry enterprises during the production process are still relatively backward. Under such realistic conditions, there is an urgent need for environmentally friendly binders, and phosphate inorganic binders have emerged.

​Currently, most of the existing direct reduced iron production processes in the world use the briquetting process to solve the problems of DRI such as high powder content, low density, flammability, large dust, and insufficient latent heat utilization. Briquetting is the method of applying mechanical pressure to agglomerate the pellets or powdered DRI produced by direct reduction into dense closed blocks. Briquetting is divided into cold pressing process and hot pressing process.

The direct reduction technology of rotary hearth furnace has been developed for nearly forty years, and the device was firstly used in the heating furnace of steel rolling, and later used to treat the iron containing waste materials. The direct reduction technology of rotary hearth furnace is characterized by low fuel quality, no need for deep processing of raw materials, simple process, good utilization of waste resources, and protection of the human environment, therefore, it has received more and more attention from the industry.

First, using a certain proportion of DRI in the smelting process of high-quality steel in EAF can improve the mechanical properties and overall quality of high-quality steel. At the same time, reasonable control of the application proportion of DRI can achieve the purpose of energy saving and increase in production, which is of great significance to improving the comprehensive benefits of EAF steelmaking. Second, the application of DRI in BF steelmaking can reduce the coke ratio of BF steelmaking and increase the output of BF steelmaking. The economic benefits of BF steelmaking are greatly improved.

Direct reduced iron has a relatively stable composition, low content of harmful impurities and relatively uniform particle size. As a high-quality raw material in modern metallurgy, direct reduced iron plays a vital role in metallurgy. In recent years, the application of direct reduced iron in the smelting of high-quality steel in electric furnaces, blast furnaces and other smelting furnaces is relatively common, which can effectively improve the production efficiency and reduce the coke ratio, and has positive significance for improving the overall efficiency of modern metallurgy. In addition, direct reduced iron can also be used in LD converter coolant and flat furnace effective metal raw materials, can also play a positive role.

Directly reduced iron added to the electric arc furnace proportion varies, if the proportion of direct reduction of iron is less than 30%, can be used cans of material loading. The bottom of the basket is filled with light scrap, followed by heavy scrap and direct-reduced iron, to avoid too much lumping of direct-reduced iron. However, when the arc heats the thicker layers of direct reduced iron, the molten metal fills the spaces between the direct reduced iron and condenses, causing the charge to sinter into a single piece, making it difficult to add the charge as a whole to the molten pool and extending the melting cycle. When more than 30% of the charge is added in batches, due to the slow heat transfer of the direct-reduced iron, the relevant technical indicators are poor, and should be fed into the furnace by means of continuous charging.

Under the background of the rapid development of the world's iron and steel technology, the pace of innovative technology methods is also accelerating, as a kind of efficient blast furnace steelmaking technology, direct reduction iron technology effectively improves the quality of iron and steel products. The article proposes four direct reduction iron production technologies.

Based on the conditions in these aggregates, a test series to experimentally simulate the first few seconds after charging DRI was defined. DRI samples with different carbon contents and hot briquetted iron (HBI) were immersed in high- and low-carbon melts as well as high- and low-iron oxide slags. The reacted samples were quenched in liquid nitrogen. The specimens were qualitatively evaluated by investigating their surfaces and cross sections.

Since the European Union defined ambitious CO2 emission targets, low-carbon-emission alternatives to the widespread integrated blast furnace (BF)—basic oxygen furnace (BOF) steelmaking strategy—are demanded. Direct reduction (DR) with natural gas as the reducing agent, already an industrially applied technology, is such an alternative. Consequently, the melting behavior of its intermediate product, i.e., direct reduced iron (DRI), in either an electric arc furnace (EAF) or a submerged arc furnace (SAF), is of great interest. Based on the conditions in these aggregates, a test series to experimentally simulate the first few seconds after charging DRI was defined.

The study explores the influence of binder type, binder dosage, and moisture content on the characteristics and properties of the pellets. The efficiency of binders was characterized by the moisture content, drop number test, cold compression strength, and H2 reduction of pellets. For dry pellets, CMS was superior among other binders including bentonite in developing dry strength. After firing, the pellets produced by the partial replacement of bentonite with 0.1 wt.% KemPel demonstrate a performance nearly identical to the reference pellets. While the complete replacement of bentonite with organic binder shows a lower performance of fired pellets compared to the reference, it may still be suitable for use in DR shaft furnaces. The cold-bonded pellets demonstrate a superior reduction rate compared to fired pellets.