The fluidity of melt formed in the iron ore sintering process seems to be an important factor for agglomeration of raw mixtures, since the formed melt plays the role of bonding the un-fused coarse iron ores. In the present study, sintering experiment was conducted in order to find the optimal particle size of fine iron ore for maintaining the fluidity of melt under the condition with low slag ratio and a large amount of limonite ore in the raw mixtures. As the results, it was found that the fluidity of melt lowered by decreasing the slag ratio and by increasing the amount of limonite ore in the raw mixtures. Furthermore, the optimal particle size of fine iron ore to maintain the fluidity was found to be different depended on the slag ratio in the raw mixtures and the combined water content in the iron ore.

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Sintering experiments were conducted in order to suppress the formation of large pores existed in the assimilated parts of sinter produced using pisolitic limonite ores. Modeled pseudo-particles, which consisted of coarse iron ore particle as cores and fine mixture of hematite ore and limestone as shell layer, were used in the present experiments. CaO concentration of shell fine was varied in three levels, i. e. 10, 20 and 30 mass% and ratio of shell fine was varied in two levels, i. e. 30 and 50 mass%. CaO concentration and ratio of shell fine were regarded as indices of apparent viscosity and volume of melt formed during heating. The influence of CaO concentration and the ratio of shell fine on the behavior of large pore formation during heating were examined by a microscopic observation. The mean diameter and area fraction of pores existed in the assimilated part of specimen were also measured. The results obtained were as follows:
1) With increasing CaO concentration and the ratio of shell fine, the area fraction and number of pore were decreased; the suppression of the large pore formation was achieved.
2) The decrease in both of the area fraction and number of pore depend on the lowering apparent viscosity and increasing volume of melt formed during heating.
3) The lowering apparent viscosity of melt is more effective to suppress the formation of large pore than increasing volume of melt.
4) It is clear that the suppressive effect is resulted from the promotion of coalescence of bubbles due to the lowering apparent viscosity of melt formed during heating.

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To cope with the highly volatile market of freight rate in recent years, both shipping and shipbuilding companies require a tool for designing the structure of fleet that satisfy the economic demand. The authors use a numerical simulation of bulk carriers to evaluate the optimal portfolio of ships by their size and routes. In this study, we simulate the transportation network of iron ore carriers using multi agent approach. It shows the operation cost, shortage risk of iron ore stocks in steel manufacturing companies. We also discusses the economical benefit of combination trade and remedy operation for the congestion of ships in a port caused by accidental breakdown of its loading functions.

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Ironmaking blast furnace is a reactor to produce molten iron. In the furnace, iron ore and coke particles are packed in layer-by-layer structure. Iron ore is heated up, reduced, softened, and then melted. During these processes, ore layer deforms and its permeability is deteriorated. It is known that excessively high pressure drop causes in instability of blast furnace operation. Recently, a technique to mix coke particles into the ore layer is attracting interests. Thus, it is important to understand the deformation characteristics of iron ore layer that contains coke particles. In this study, the deforming ore layer was modeled by using Discrete Element Method, and the deformation behavior of coke mixed ore layer was discussed through numerical analysis.

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製紙パルプ廃液からの苛性ソーダの回収の省エネルギー化を達成するために, 従来の薬液複分解によらない直接苛性化プロセスの主要装置である流動層方式高温苛性ソーダ回収反応装置の開発を実施した。このプロセスでは, パルプ廃液に含まれる炭酸ナトリウムを高温で高純度と反応させフェライトを生成し, 加水分解で苛性ソーダを回収するもので, 生成鉄酸ナトリウムを加水分解の後, 乾燥工程を経てをリサイクル再使用することに特徴を有する。本研究では, 500mm角流動層よりなる高温反応装置を連続運転することにより, 反応装置の好適な操作条件, 運転特性ならびに反応特性を明らかにした。その結果, 0.2～1mmの高純度を流動媒体・反応剤として気泡流動層を形成し, 1,173～1,273Kでパルプ廃液中の有機分を燃焼させ, 廃液中の炭酸ナトリウムをと反応させるのが好適であることを示した。加えて, 流動層の定常運転を阻害する流動媒体・反応剤粒径の痩少の対策として0.2mmアンダー粒径の粉状物の約50%を最低限の造粒割合として造粒し, これを反応装置に供給することによって流動層を恒常的に運転でき, 苛性ソーダ回収が図れることを, プロセスシミュレーションにより予測し, 40時間におよぷ連続運転にて実証した。

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Fluorescent X-ray analysis of iron contents in iron ores by glass bead technique has been theoretically studied. Calculation has been made on FeKα fluorescent X-ray intensity in Fe-O binary sample and in Fe-O-impurity ternary sample in various fusion procedures by means of theoretical formulas for fluorescent X-ray intensity.
The results are as follows:
1. In the comparison of characteristics of various fusion procedures, the intensity decreases, the derivative of calibration curve increases and matrix effect decreases with X-ray absorption of glass bead. For example, in the procedure in which lanthanum oxide is used as reagent, matrix effect is low and lanthanum oxide is useful as heavy absorber, while vanadium oxide has a little effect as heavy absorber and matrix effect is not low.
2. In the procedure in which sodium tetraborate is used as flux, calibration curve for iron-oxygen binary system sample is made, and FeKα intensity is calculated for iron-oxygen-impurity ternary system samples when impurity is substituted with oxygen in iron-oxygen binary system sample.
Theoretical correction factors are derived from the change of FeKα intensity. It is shown in experiments that these correction factors have an effect on analysis of iron content.

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木質バイオマスを

の共存下でガス化を行った。を共存させても，可燃ガスの生成量に変化はなく，炭酸ガスのみが増加した。ガス化後の残渣中のは，ほぼ金属鉄にまで還元されていた。このとき，タールおよびチャー成分は減少していた。このことからタールやチャーがを還元したと考えられる。炭酸ガス雰囲気で木質バイオマスのガス化反応を行った所，炭酸ガス供給量より排出量の方が少ない結果となった。これは炭酸ガスが一酸化炭素等に還元されたためであり，ネガティブ・エミッションを実現する意味で重要である。この時においても，は約66％が金属にまで還元されていた。バイオマスから回収されたエネルギーは，の還元エネルギーを含めると，その90％以上が回収された。

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多量の鉄鋼原料の取引時には鉄成分の純度を有効数字4けた以上の精度で求められることが多い．従来はその要求にこたえるために滴定法で分析を行ってきた．しかし，滴定法による分析法は熟練を要し，簡便な方法が求められている．そこで，比較的精度の高い結果が得られるフローインジェクション法による中の鉄を有効数字4けたの精度で分析する方法を開発した．最適フローシステムとして一流路を選択し，安定着色成分測定ではダンパーの使用により相対標準偏差（RSD）0.068％ を確認した．また，化学反応のばらつきによる精度低下を避けるために，最適呈色試薬の選定に6けたの測定精度をもつストップトフロー法を利用した．これにより，従来安定とされていた鉄錯体の不安定性が比較され，結果として呈色試薬にタイロンが選定された．試薬濃度，pH，反応コイル長さ等の条件を選定し，標準試料に本法を適用した結果，一部の試料では滴定法の精度に勝る結果が得られた．全体としては滴定法に若干劣るものの，有効数字4けたの精度を有する精密分析法を確立できた．

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The purpose of this paper is to report the results of the plant experiments concerning the magnetic roughing concentrator for low grade iron ore which had been carried out since 1964 in theKamaishi mine.
The concentrator manufactured for trial have the construction illustrated in Fig. 1, Photo-1 and-2. It consists mainly of a shaking feeder having the same mechanism as a shaking table and a drum type magnetic concentrator being deeply immersed in water.
Ore particles are previously stratified by the shaking motion of the feeder, hence magnetic particles are reasonably attracted to the magnetic separator at the top of the drum. The predominating characteristics of this rough concentration process have been evidently recognized in the previous investigations.
The concentrator have the dimensions of a total height of 3, 115mm, a total length of 4, 450mm and a total width of 1, 130mm. The diameter of the separation drum is 1000.8mm, the effective span of the drum is 120mm and the maximum strength of the magnetic field on the surface of the drum is 1, 200 Oe.
The influences of feed rate, the revolution rate of the drum, the inclination and the shaking rate of thefeeder and its stroke length on the separation results are investigated. Experimental results are tabulated in tables 4, 5 and 6. In coarse ore separation (spiral separator tailing, table 4) the recovery of magnetic Fe remains about 65%. On the other hand in medium size (flotation tailing, table 5) and fine size (thickener spigot, table 6) the separation recoveries are keeping higher values of 80-94%.
Cleaning of the rougher concentrate of this separator is carried out by using a small scale Ferrogum magnetic separator. We obtained the final concentrate of magnetic Fe c=58% under the recovery of E=98%.

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Research Association of Pulp and Paper Technology has started R & D of ferric oxide direct causticization process which enables the abbreviation of conventional lime kiln thus saving oil consumption in pulping industry.
For the recovery boiler, we study 3 types of furnace, fluidized bed, fixed bed, and spouted bed. We are now in the stage of bench scale study whose capacity is 120 kg/h dry based solids. Among 3 types stated above, the fluidized bed system seems promising from the data obtained through labo and bench scale investigations.
The authors describe the R & D procedure for the fluidized bed process, and show the results of bench scale study mainly obtained with 500 mm square diameter fluidized bed.

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　石炭，，穀物等のドライバルク貨物は，産業の基礎素材や食糧原料等であり，これらの貨物の海外からの輸送は，我が国の産業活動や国民生活の生命線の一つとも言える．しかし，ドライバルク貨物は，特定荷主のための不定期輸送であり，企業専用ターミナルで取り扱われることも多いため，その全体像の把握に困難な部分がある．この点を踏まえ，本研究は，品目別の輸送船及び積出港データを用い，寄港実績データより輸送実績を特定する手法を構築し，北東アジアへの三大バルク貨物の輸送実績を分析したものである．中でも，当該バルク貨物を荷揚げするバースの諸元と，輸送船の船型との関係に着目した．

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The chemical compositions of iron ore used for iron making are mainly hematite (Fe₂O₃), magnetite (Fe₃O₄) and goethite (FeOOH). The uranium (U) and thorium (Th) of natural radioactive elements are contained with ppm level as impurity elements in these iron ore. The purpose of this study is a estimation U and Th isotopes behavior for in various iron ore by an α spectrometry. Samples were the iron ore from Australia, Brazil and India. After those samples were dissolved by a microwave method, U and Th were separated from matrix elements by the chemical processes were mainly a Fe(OH)₃ coprecipitation method, a NdF₃ coprecipitation method and a Nd(OH)₃ coprecipitation method. Thereafter, U and Th were only separated by two steps anion–exchange chromatography. Further, Sm(III) carrier as an internal standard was added in U fraction or Th fraction, and a SmF₃ coprecipitation was done with HF solution. These precipitation samples were measured by an α spectrometer system. The α peak of ²³⁸U, ²³⁴U, ²³²Th, ²³⁰Th, ²²⁸Th and ¹⁴⁷Sm of these fraction were determined. As the results, U and Th isotopes in all of the iron ore were able to determine within 15% of RSD. And those were found that a relation of a radioactivity of ²³⁸U–²³⁴U was a radioactive equilibrium, and that a relation of a radioactivity of ²³⁸U–²³⁰Th was a radioactive disequilibrium. In addition, it was indicated that a positive association between their disequilibrium and the chemical compositions of ferrioxide in various iron ore.

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　北極海航路を用いて北極圏で産出される及びLNGの我が国への輸送コストについて検討した．・LNGそれぞれについて，北極海航路による輸送シナリオのほか，既存産地からの輸送シナリオを検討し，輸送コストを算出した．の輸送コストでは，燃料費が最も大きな割合を占めた．北極海航路輸送では，距離短縮と航行速度低下によって燃料消費量が削減され，砕氷船支援料等のコスト増分を相殺した．LNG輸送コストでは，減価償却費が大きな割合を占めた．北極海航路の場合，航行日数が削減されて，高額な船価に起因する減価償却費増分が相殺された．以上より，北極圏で算出される天然資源を北極海航路で輸送する場合，輸送コストは，競合する既往産地からの輸送コストに対して競争力を持ちうることを示した．

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