Chief Transformation Offcer, Reframax Engenharia Ltda.

Luciano Fernandes LOPES

Masatsugu KITAMURA

As the importance of carbon neutrality continues to grow, reducing heat loss in high-temperature processes has become a critical issue directly linked to saving energy and reductions in CO2 emissions. This report reviews the mechanisms of heat loss and organizes the functions of refractories into four categories: insulating materials, high-strength insulating refractories, low-thermal-conductivity refractories, and rapid-drying monolithic refractories. This classification provides a technical foundation for applying material properties, structural design, and installation technologies in an integrated manner to address complex heat-loss factors, including heat dissipation, heat storage, temperature drop during operational stoppages, and thermal consumption during installation. Furthermore, the classification serves as a common framework that supports consistent discussion from material development through lining design to installation processes and contributes to reducing environmental impact across the entire refractory lifecycle by enabling synergy with green refractories aimed at reducing CO2 emissions at the raw-material stage.

Kentaro UEMICHI, Takashi NEMOTO, Hidenori TADA and Toshihiko KANESHIGE

As a pioneer refractory insulation material supplier, the authors’ company (Isolite Insulating Products Co., Ltd.) has been developing and providing various refractory products centered around key heat insulation technology. Looking back on the history of refractory insulation materials, it becomes clear that refractory insulation materials have been contributing to the evolution of industries by developing new heat insulation technologies which satisfy the requirements of a given era.

Ryo TSUKADA, Takahiro KAGO, Shigeru KOMORI and Kazuya NAKABO

For the purpose of reducing heat loss carried away by skid pipe cooling water in reheating furnace, ceramic fiber blended castable refractory with low thermal conductivity and high mechanical strength was developed. Because of the high apparent porosity of the developed castable refractory obtained by blending a large amount of ceramic fiber with uniform dispersion in castable refractory body, the thermal conductivity is substantially lowered. In addition, sufficient erosion resistance against mill scale and mechanical strength are imparted to the developed castable refractory. It is expected that, by applying the developed ceramic fiber blended castable refractory for reheating furnace skid pipe, waste heat carried away by skid pipe cooling water will be reduced, accompanied by extension of refractory service life.

Haysler LIMA, Vladnilson RAMON and Douglas GALESI

The time has come in the recent history of mankind when efforts to reduce emissions of pollutants, especially CO2, are no longer just an intention among the countries of the world community but must become mandatory actions for our future. In this sense, innovative solutions that reduce the emission of fossil fuels, and that have an issue of energy conservation, become attractive in this current scenario. There are several refractory materials used in steel ladles, and when it is chosen to use Magnesia-Carbon and Alumina-Magnesia-Carbon, in the metal line, although with good operational performance, because they contain carbon, it can be incorporated into steel, in what is defined as the phenomenon of carbon pick up. In addition, the presence of carbon in the refractory lining increases the thermal loss of the ladle, disfavouring the energy balance of the melt shop. 
This work aims to disseminate the knowledge acquired in the use of carbon-free steel ladle refractories (ALTIMA) and their beneficial influence in the steel industry, demonstrating that their use can be an important ally in energy savings, reduction of costs and, at the same time, an important factor in the reduction of polluting emissions

Natsumi HIGASHIKAWA, Kiyoyuki KOMATSUBARA, Hikaru TAKUMI and Kazuya NAKABO

Lowering of EAF inside temperature during gunning repair work conducted at intermediate interval between production causes slowdown of operation rate and increases of electric power consumption which is required to recover from the lowered temperature. We developed a new gunning material with superior adhesivity at high temperature. Its effects were evaluated in this research work. It was clarified with a hot gunning test on a high surface temperature test panel that, in comparison with the merely 2 % adhesion rate of conventional gunning material, the newly developed gunning material exhibits 45 % adhesion rate. It was confirmed with numerical simulation that, due to such difference in adhesivity at high temperature, the waiting time for starting repair work is shortened by roughly 75 % in association with reduction of heat loss during recovery from lowered temperature of hot-heeled molten steel by one half. It is expected that new repair work operation with the developed gunning material will contribute to improvement of operation rate, energy saving and lightening of the environment load in EAF operation

Haysler LIMA, Douglas GALESI, Lucas ALVARENGA, Vladnilson RAMOS, Ronaldo BORGES, Magno MENES, Marcos AUAD, Márcio VERÍSSIMO and Matheus SANTOS

The performance of a Steel Shop depends on the stability of its equipment, and the thermal balance of the BOF is essential to guarantee the thermal stability of liquid steel, reducing downtime for reheating, adjusting the tapping temperature, as well as avoiding thermal losses to the metallic shell. One way to improve the thermal balance would be the use of insulators in combination with the working refractory material. This work is unprecedented in the use of insulators in BOF, with implementation at the Usiminas Steel Shop in BOF#4. The results observed during the campaign increased BOF productivity, reduced downtime for reheating, improved refractory lining and increased shell life.

Edwin AALBERS, Peter PLAIZIER and Johannes BOERSMA

Gouda Refractories, part of the Shinagawa Refra Group, develops advanced refractory solutions designed to improve energy efficiency and sustainability in high-temperature processes. By integrating high-performance bricks and castables with superior insulating properties, chemical resistance, and mechanical strength, these materials significantly reduce heat loss, lower fuel consumption, and extend lining life. Applications span non-ferrous metals, petrochemical, and iron & steel industries. This paper highlights the thermal performance optimization and environmental benefits achieved through innovative energy-saving refractory technologies.

Takuma KANAGAWA, Takashi IIDA, Kenji SUZUKI and Yuki NIIYA

“SBC”, a new castable refractory for the blast furnace main trough was developed by applying a new binder system.“SBC”is characterized by low temperature dependence setting time as well as suitable hydrogen gas generation behavior. This results in a sound blast furnace trough body with no hollow or void defects induced by abnormal generated gas build-up. Construction can be carried out with reduced fluctuation of setting time, in other words, improper setting of castable refractory, such as, abnormally fast setting or not setting for an extremely long time can be eliminated.

Tsuyoshi UEDA and Hiroyasu NIITSUMA

Alumina clogging is one of the issues associated with single-port submerged entry nozzles for blooms and billets. To address this, we developed a product that combines the SSB-Nozzle (Shinagawa Self-Braking)—a design expected to reduce alumina clogging and discharge flow velocity— and existing technologies such as “carbon-free inner material” and “annular step inner geometry”. Operational evaluations gave excellent results in which a significant reduction in alumina clogging was confirmed.

Chiho KURIYAMA and Junya ITO

To contribute to reducing the environmental impact in mold powder production, utilizing waste-derived materials as alternative raw materials is an effective approach. This study focused on recycled raw material produced from photovoltaic glass (PV glass) used in solar panels, hereafter referred to as R-PV glass. The melting behavior and thermal insulation of mold powders formulated by utilizing R-PV glass and adjusting the composition of other raw materials were evaluated. The results showed that the developed mold powder exhibited melting characteristics comparable to those of conventional products, while demonstrating 
improved thermal insulation. Adding R-PV glass can help recycle waste materials efficiently and may also boost steel quality by providing better thermal insulation due to its exothermic characteristics.

Madoka HAGA and Atsuji KOBIKI

The adoption of thermal insulation technologies to suppress heat conduction and radiation is essential for mechanical components, piping, and structures exposed to high-temperature conditions. In particular, thermal insulation coatings that achieve both consistent application and high insulation performance are important for complex-shaped components, such as automotive exhaust system parts and industrial plant piping. This report describes the development of a thermal insulation paint with appropriate workability by incorporating hollow ceramic particles primarily composed of silica and alumina. The developed coating 
exhibited improved adhesion under heating conditions up to 600 ℃ and reduced thermal conductivity to 0.1–0.3 W/m·K, thereby achieving a balance between applicability to complex-shaped components and thermal insulation performance.