JFE Steel Corporation developed the hydrogen-based gas fuel injection technology for sintering machines to improve sinter quality without increasing coke breeze ratio. With the technology, it is possible to extend the temperature zone between 1 200°C and 1 400°C by injecting the gaseous fuel from the top surface of the sintering machine as a partial substitute for coke breeze. Theoretical and experimental studies were carried out to verify the effect of the gaseous-fuel injection technology on pore structure in the sinter cake with the X-ray CT scanner and sintering pot test.It is important to hold the temperature between 1 200°C and 1 400°C in order to produce high strength and high reducibility sinter. The liquid phase ratio can be increased with extending the proper temperature zone by applying the gaseous fuel injection technology. The increase in liquid phase ratio promotes the combination of pores (1-5 mm) and sinter strength is improved. At the same time, the pores over 5 mm growth are promoted and the permeability is improved in the sintering bed. Moreover, the low-temperature sintering process depresses the iron ore self-densification. Micro pores under 1 μm remain in unmelted ores and improve sinter reducibility. As a result, the technology enables to improve the pore structure in the sinter cake and sinter quality.The technology was put into commercial operation at Keihin No. 1 sinter plant in January 2009 and stable operation has continued up to the present. As a result, the energy efficiency in the sintering process is greatly improved, and it has been achieved to reduce CO2 emissions by a maximum of approximately 60 000 t/year at Keihin No. 1 sinter plant.

The viscosity of the melts formed in the sintering reaction was measured for evaluating the fluidity of the melts, which play a crucial role in the sintering process. Using the sphere draw-up method carried out the measurements of high temperature viscosity. With low-melting point compositions of the Fe 2 O 3 -CaO-SiO 2 system, the viscosity of high SiO 2 content melts (Fe 2 O 3 /CaO/SiO 2 ϭ38.5/34.5/27.0 weight basis) was 5 times higher than that of low SiO 2 content melts (Fe 2 O 3 /CaOϭ80/20). The viscosity of low SiO 2 content increased with addition of Al 2 O 3 and SiO 2 . Similarly, with melt compositions generated from actual ores, viscosity depended on the contents of Al 2 O 3 and SiO 2 .Based on the results, the viscosity of the melted liquid was estimated from the chemical composition, and the viscosity of the solid-liquid coexistence phase was also evaluated using a viscosity calculating equation for suspensions. The viscosity distribution of the solid-liquid coexistence phase at 1 300°C in the ternary composition system Fe 2 O 3 -CaO-SiO 2 was obtained.

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Dry powder inhaler (DPI) formulations have been utilized in the treatment of respiratory disease [1][2][3] and for systemic administration.4 -7) They have become common in the inhalation therapy field because of various advantages, such as being free from anti-environmental propellants 8) and ease of use with portable small devices.DPI formulations with fine drug particles and coarse carrier particles have been widely used for a long time. Usually their components are simple and they can be manufactured with conventional equipment. Therefore, they appear to be a valuable option as the formulation for clinical trials, especially in the early stages of development. The carrier particles play the critical role in preventing the agglomeration of fine drug particles which possesses high surface energy due to their large specific surface area. On the other hand, it is necessary to achieve the high deposition in the deep lungs to satisfy the required bioavailability. Because only small particles (aerodynamic diameter below 5 mm) can reach the lungs, fine drug particles should be detached from the coarse carrier particles through the inhalation process. The percentage of small particles to the entire dose is defined as fine particle fraction (FPF). Therefore, FPF is an index of the extent of deposition in the lungs.Studies have been conducted to clarify the factors that control the inhalation properties of the carrier-based DPI formulations. [9][10][11][12][13][14] Many studies focused on the carrier surface properties especially rugosity and/or coverage of high energy binding sites. 10,[15][16][17][18][19][20][21] Surface energy of particles would be one of the major factors influencing the inhalation profile of DPI including FPF. 22,23) However the mechanism of FPF increase has not been fully clarified so far. This seems to be because the inhalation profile of DPI is affected by various factors including particle size, morphology electrostatic charge and inhalation condition. 10,12,[24][25][26] Therefore, there is a need for preparation and characterization of series of powder samples that are different in surface properties but similar in other properties and compare them under the same inhalation condition.Mechanofusion can modify the surface energy of lactose carrier particles without drastic change of the particle size and can make the particle shape round to lessen the differences.Inverse gas chromatography (IGC) has been utilized to examine the effect of surface energy on the inhalation behavior of DPI. We reported that mechanofusion on a lactose carrier changed the carrier's surface condition and the inhalation properties of DPI formulations containing the lactose carrier and Compound A.27) The Andersen cascade impactor (ACI) profile suggested that the increase of FPF was accompanied by the decrease of the interaction between Compound A and carrier particles. Begat et al. also reported that mechanofusion of lactose with Mg-St reduced the interaction between drug and lactose particles.28) Mg-St is known as lubri...

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