Hideharu Hirosue

Bio: Hideharu Hirosue is an academic researcher from Kyushu University. The author has contributed to research in topics: Geometric standard deviation & Airflow. The author has an hindex of 2, co-authored 4 publications receiving 56 citations. Previous affiliations of Hideharu Hirosue include Industrial Research Institute.

Elutriation of fines from fluidized bed

Abstract: Transport Disengaging Height (T. D. H.) was studied theoretically and experimentally for both continuous and batch fluidized beds. The theoretical elutriation rate of fines above the T. D. H., Vt, was calculated by use of the Maxwell-Bolzmann energy distribution, and it showed good agreement with the experimental value for the continuous fluidized bed. The theoretical values of the T. D. H., which were defined as Z at V=1.01Vt, coincided fairly well with the present and reported experimental results. The elutriation height coefficients a were found empirically to increase with increase in particle diameter and with decrease in superficial velocity.

Hold-up in a Rotary Drier

Abstract: 回転乾燥機内における材科の平均通過時間はその設計, および, 操作上重要な因子である。そこで, これと関係の深い無風時および通風時の保有率について研究した。まず, 機内における単一球形軸子の運動を解析し, さらに, 掻上板の形および数を考慮にいれた掻上容量を定義した。ついで, 無風時および通風時保有率の次元解析式を導き, 各式の係数と指数とを実験により求めた。これらによれば既往の文献値をもおおよそ整理できる。

The Behavior of Particles in the Cross Section of the Rotary Dryors

Abstract: 回転乾燥機または冷却機横断面内における粒体の挙動を正確に把握することを試みた。まず, 掻上板上の粒体層上面の粒子のすべり運動, 掻上板を離れたのちの落下運動などを考慮して, 粒体の見かけの落下軌跡を求めた。これと実測値とを比較したところ, 両者はよい一致を示した。つぎに, 粒体の落下終了回転角についても検討を加えた。さらに, 粒子の真の落下軌跡と, 掻上板上の落下すべき粒体層容積対回転角との関係を用いて, 設計基準保有率を求め, 実測値と比較したところよい一致が得られた。

Studies on Residence Time Distribution of Particles in Rotary Dryers and Coolers

Abstract: It is found that the residence time of particles flowing through rotary dryers and coolers under the conditions of no air flow and air flow can be expressed by the logarithmic normal distribution, and also that the median of residence time is approximately equal to the apparent mean residence time.As the empirical equation for the latter had been obtained by the authors, the empirical equations concerning the geometric standard deviation, which is the other parameter in the distribution function, are studied in this paper. As a result, Eq. (8) and Eq. (10), respectively, are obtained as the empirical equations of the geometric standard deviation under no air flow and air flow. These equations approximately correlate the experimental results within the accuracy of ±20%. It is also found from the both equations that the geometric standard deviation under air flow is large in comparison with that under no air flow.

Transport Phenomena and Reaction in Fluidized Catalyst Beds

Abstract: Publisher Summary Flow properties of the fluidized catalyst bed (FCB) are different from those of other conventional fluidized beds. The different treatment required is very significant for research and development on fluidized catalytic beds. This chapter discusses the factors affecting the flow properties. These properties include particle size distribution, also heat and mass transfer, and mixing properties. In the FCB, the dilute phase plays an important role in advancing the catalytic reaction when reaction rates are high. This factor provides a basis for identifying the appropriate reaction model and clarifying the effect of the dilute phase on selectivity and stability. The simplified theory for a bubble column is applied to understand particle circulation in the FCB. As a result, it is possible to analyze flow patterns of bubbles and “emulsion.” This chapter considers the uses of fluidized beds for catalytic reactions, using a viewpoint quite different from studies directed toward the physical handling of solid particles or toward gas–solid noncatalytic reaction. Particle size distribution has a great effect on most aspects of fluidization. Fluid beds are usually operated in the turbulent-flow region to obtain good contact and sufficient throughput of reactant gas. The uniformity and contact efficiency of a fluid bed can be improved by immersion of a surface within the bed.