著者

貝掛 敦

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan (ISSN:18816118)

巻号頁・発行日

vol.123, no.12, pp.686-688, 2007-12-25

被引用文献数

5

---

HYUGA SMELTING CO., LTD. (HYUGA) was established in 1956 by SUMITOMO METAL MINING CO., LTD. ELKEM process which consists of rotary kiln and electric furnace was introduced to smelt nickel ores from Indonesia and French New Caledonia and to produce ferronickel mainly used for stainless steel.<BR>For the last decade, as for the improvement of rotary kilns, HYUGA has upgraded the off-gas fans and introduced the scoop feeders for coal charge addition. As the result, the high temperature zones of kilns have been expanded toward kilns' charge end side and the feed rates of kilns have drastically increased. <BR>As for the improvement of electric furnaces, HYUGA renewed one of two electric furnaces in 1995 and the other in 2006. At these renewals, each transformer was upgraded and copper-cooling system was introduced into one electric furnace in 2006. Since then, HYUGA has implemented low current, high voltage electric furnace operation. This system improves the response to a wide range of ore chemistry, and it enables safe, high-load stable operation with high productivity matched to the energy situation.

著者

三宅 裕

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.124, no.9, pp.554-561, 2008-09-25 (Released:2011-02-15)

参考文献数

26

被引用文献数

1

---

The exploitation of copper in Ancient Western Asia has a long history. Already in the Neolithic period malachite was used as raw material for bead and pigment, and then native copper was shaped into small objects by hammering and annealing. Based on the evidence from copper objects and workshops found in Iran and Anatolia, smelting and casting were carried out in the 5th millennium B.C. In the early copper production it is likely that the oxide ores such as malachite were used as raw material which was smelted in the crucible set on the shallow pit furnace with the aid of blow pipes. The advent of alloy in the late 4th millennium B.C., another significant development in early metallurgy, might make casting easier and more successful. The first copper alloy was arsenical copper which continued to produce until the end of the Middle Bronze Age along with bronze, an alloy of copper and tin. By the second half of the 3rd millennium the copper production in the vicinity of the sources became prevailing. The Late Bronze Age shipwrecks in the Mediterranean provide good evidence for the long distance trade of copper and tin in the shape of ingot.

著者

松本 佑美 鈴木 亮利 千葉 雄大 新井 剛

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.131, no.8, pp.481-486, 2015

被引用文献数

3

---

Palladium will be most increased demand in rare metals because the use of electrical and electronic fields in the future. Therefore, it is nesessary to construct the stable supply of resource in our country. Currently, the separation and recovery of palladium from urban mines have trying to carry out the solvent extraction method using the dihexylsulfide (DHS) extractant as the mainstream. However, DHS have some problems which the extraction process is lengthening because DHSs extraction rapid is so slowly. In this study, it was focused that triphenylphosphine (TPP) as an alternative DHS extractant. TPP shows the extraction rapid is about 5-6 times higher than DHS extractant. Therefore, we have been investgating to establish the Palladium separation and recovery process using TPP extractant. In our previous work, it was found that the multistep extraction is possible to separate Pd(II), Au(III)and Ni(II) from the coated electronic parts waste which use Cu as base material using TPP extractant. In this work, we investigated that the separation and extraction behavior of Pd(II), Au(III), Ni(II) and Cu(II) using TPP extractant. Furthermore, we considered that the separation and recovery process from the coated electronic parts waste by the extraction method with TPP extractant.

著者

大熊 宏

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.124, no.1, pp.87-94, 2008-01-25 (Released:2011-01-25)

参考文献数

15

被引用文献数

4 2

---

The simulator for geological CO2 sequestration was developed by adding to a commercial compositional oil reservoir simulator the functions of geochemical reactions and fracture occurrence/fault activation. The resulting simulator, GEM-GHG, was verified with a number of validation runs and is believed to be one of the most advanced and robust simulators of this kind today.The simulator was made use of for various purposes throughout the pilot CO2 injection test at Nagaoka, Japan. During the planning stage, the simulation studies were conducted repeatedly to confirm the technical feasibility of the test plan. Once CO2 injection began, the objectives of simulation were history matching and interpretation of the observed injection performances. Reasonable agreement of the bottom-hole pressures and the breakthrough times was attained by varying uncertain parameters such as relative permeability curves, areal changes in permeability, and vertical permeability.The final aquifer model of the history matching was employed to predict the long-term CO2 movement. The results implied that the CO2 movement would be very limited after the end of injection and the injected CO2 would essentially remain within the injection zone in the pilot test area.

著者

角谷 博樹 立田 則男 工藤 万雄

出版者

The Mining and Materials Processing Institute of Japan

雑誌

資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan (ISSN:09161740)

巻号頁・発行日

vol.113, no.6, pp.440-445, 1997-06

被引用文献数

2

著者

佐々木 久郎 ディンディウェ チャールズ 安達 毅

出版者

The Mining and Materials Processing Institute of Japan

雑誌

資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan (ISSN:09161740)

巻号頁・発行日

vol.117, no.7, pp.604-612, 2001-07-25

参考文献数

17

被引用文献数

1

---

In this paper, a new concept for final pit shape in open pit design, Best Positive Inverted Truncated Cone (BPITC) algorithm, is presented for feasibility study and basic scheduling. Five mineral deposit models were used for eventual surface mine design optimization. Initially, geological reserve models were simulated by the utilization of GSLIB using randomly and regularly spaced drill hole data. Effects of varying anisotropy on the obtained metal quantities in reserves were also investigated. The BPITC was successfully applied to 100-times simulated deposit data set using Geostatistical simulation code GSLIB. The optimization results by BPITC were compared with those obtained by Positive Moving Cone (PMC) and Dynamic Cone (DC) based algorithms for the same mineral deposit models. The obtained results indicate that BPITC is superior to all the other optimizers. Concequently, the frequency distribution curves of profits and pit incremental feature by BPITC give effective information on mineral project decision-making and mining sequencing respectively.<BR>The conclusions from this study are summarized as follows:<BR>1. It was proved that for any type of deposit, the usage of correct anisotropic factors used in GSLIB lead to correct evaluation of reserves.<BR>2. All the profits / benefits computed for all the five model deposits show that a newly developed scheme named as BPITC can always indicate optimal solutions for final pit designs.<BR>3. Conclusively, the frequency distribution curves of profits and pit incremental feature by BPITC give effective information on mineral project decision-making and mining sequencing, respectively.

著者

阿部 一郎

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan (ISSN:18816118)

巻号頁・発行日

vol.126, no.8, pp.477-481, 2010-08-25

被引用文献数

1

---

Sumitomo Metal Mining Co., Ltd. focuses on the "non-ferrous major class" mining company as its business strategy and the Pogo Gold Mine is situated at a very important position to achieve the goal. The mine was started with the grassroots exploration in 1991, as a first exploration project in which Sumitomo Metal Mining has majority share of project. A couple of gold deposits were discovered and defined during the exploration stage and the project was evaluated feasible to develop. The environmental permit process was started in 2000 and completed in 2004, in which especially the ore process flow was designed very carefully to prevent the surrounding nature from any impacts. The intensive construction works were initiated after approval of the environmental permits and twenty months had been spent to start ore processing in February 2006. The mine adopts the drift and fill mining method with paste backfill by using tailings from the ore process. Currently about 2,400tonnes/day of ore are mined and processed, which are above the plan in the feasibility study.

著者

荒井 健男 咲間 修平 佐藤 義倫 篠田 弘造 JEYADEVAN Balachandran 田路 和幸

出版者

The Mining and Materials Processing Institute of Japan

雑誌

資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan (ISSN:09161740)

巻号頁・発行日

vol.119, no.12, pp.713-720, 2003-12-25

被引用文献数

1 2

---

Stratified materials are defined as materials with nano-sized stratification that have been artificially controlled and designed. They are exemplified as a thin layer or stacked layers formed on surface of semiconductors. The present research is aiming at formation of controlled and designed stratification on surface of fine particles, leading to improvement of properties of fine particles which has been difficult to accomplish through the conventional particles engineering, and to development of novel properties created by the stratification.<BR>Here, we describe the method of the development of the nano-size CdS catalyst with stratified structure that efficiently separates electron and hole during photolysis, especially, to produce hydrogen gas from hydrogen sulfide, H₂S. Furthermore, as an approach for the development of the practical use photocatalyst, ZnS-carbon nanotube complex was also made and examined. In a way, the stratified structure is considered to enable the production of a reaction system which simulates function in biological cells. Using this catalyst in the solution mixed with various materials such as, calcium hydroxide, seawater and H₂S, we succeeded in producing about 7.5l/h m² of hydrogen gas under the sunlight.

著者

崎元 尚土 島田 荘平 大賀 光太郎 熊谷 治夫 山田 理 海保 守 安田 肇

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan (ISSN:18816118)

巻号頁・発行日

vol.126, no.10, pp.608-613, 2010-09-25

被引用文献数

1

---

CO<SUB>2</SUB> sorption on coal was estimated by two experiments, one is heat of sorption measurement and the other is <SUP>1</SUP>H-NMR measurement. In the heat of sorption measurement, differential heat of sorption (<I>q<SUB>d</SUB></I>) was compared with the calculated one. Measured <I>q<SUB>d</SUB></I> was same value with calculated one at low pressure. It decreased gradually with pressure and became lower than the calculated one. Since it couldn't be explained by the theory based on physisorption, it is estimated that the coal-CO<SUB>2</SUB> system could not be explained by only simple physisorption.<BR>In <SUP>1</SUP>H-NMR measurement, spin-spin relaxation time (<I>T</I><SUB>2</SUB>) and composition fractions of L<SUB>1</SUB>, L<SUB>2</SUB> and G were measured. Composition fractions and <I>T</I><SUB>2</SUB> of L<SUB>1</SUB> increased with CO<SUB>2</SUB> gas pressure. Furthermore, the correlation was observed between volume increments and dissolution amount at over 10 atm. It indicates that part of CO<SUB>2</SUB> sorption capacity was used to coal relaxation.

著者

晴山 渉 須藤 孝一 井上 千弘 千田 佶 中澤 廣

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.123, no.3, pp.117-122, 2007-03-25 (Released:2009-12-15)

参考文献数

29

被引用文献数

1

---

Chlorinated organic compounds such as trichloroethene (TCE) have caused soil and ground water pollution on a lot of sites. Oxidation processes which are produced hydroxyl radical are effective to remediate these contaminated sites, because they are able to degrade TCE. This paper describes photochemical oxidation of TCE with citrate ion and iron ion. Citrate ion and iron ion form some complexes (Fe-citrate complexes) which absorb the light of wavelength below 450nm. The Fe-citrate complexes were able to be decomposed TCE with black light lamp (wavelength: 320-400 nm). Approximately 50% of initial TCE concentration (100mg/L) decomposed within about 7 hours when the molar ratio of iron ion to TCE is 4 and the molar ratio of citrate ion to TCE is 4. The degradation rate of TCE using citrate ion and iron ion was lower than using oxalate ion and iron ion. The excess iron ions inhibited the TCE degradation because some of iron ions formed iron hydroxide and it absorbed lights essential for the photochemical reaction. Therefore, the photodegradation of TCE needs sufficient citrate ion to ensure for forming Fe-citrate complex formation. TCE was degraded between initial pH 2.5 and 10.6. The degradation rate of TCE was higher in the condition of acidity than the condition of alkalinity. In acidic condition, the dominant iron species was [Fe(III)(C6H5O7)] which is the important species for TCE photodegradation. On the other hand, even in alkaline condition, [Fe(II)(C6H5O7)]- existed as an Fe-citrate complex. So, this fact shows strongly that [Fe(II)(C6H5O7)]- photochemically degrades TCE under the condition of alkalinity.

著者

山崎 哲生

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.124, no.12, pp.829-835, 2008-12-25 (Released:2011-02-15)

参考文献数

31

---

Japan has a manganese nodule mining claim in the Clarion Clipperton Fracture Zones, the Kuroko-type massive seafloor sulfide deposits (SMS) and cobalt-rich manganese crusts (CMC) in Japan's exclusive economic zone (EEZ) and the continental shelves. Japan needs to use these deep-sea mineral resources as future strategic metal and rare earth element supply sources. Furthermore, the development technologies have wide variations in applying for the other food and energy supply targets in EEZ and continental shelves and the same-type resources of Pacific island nations'.Some current topics in deep-sea mineral resources development and the development technologies are introduced. Possibility and necessity of deep-sea mineral resources development for Japan are discussed.

著者

佐々木 芳宏

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.138, no.10, pp.149-159, 2022-10-31 (Released:2022-10-29)

参考文献数

25

---

油圧システムは小型で高出力であるため,産業界では大型加工機械や土木機械として様々な現場で広く用いられている。本研究では,近年著しく広帯域化が進んでいるネットワークバックボーンインフラを利用し,TCP/IPによる高速通信を油圧シリンダの遠隔制御に適用することで,現場での作業を想定した遠隔操作技術の確立を目指すことを目的とする。IPネットワークを使った遠隔操作技術において,通信中におけるパケットの遅延,揺らぎ,損失などが発生した場合,遠隔制御システムに対して制御性能の悪化を引き起こす。本研究では,反力提示を組み込んだ遠隔用油圧制御システムを開発し,通信時に発生する遅延,揺らぎ,欠損に対しパケット補償法をネットワークのエミュレーションツールであるNIST Netを用い検証した。また,オペレータの精神的作業負荷を数値化できるNASA Task Load Index (NASA-TLX)を用い精神的負担度の主観的評価を行った。以上の結果より,パケット補償の適用はNASA-TLXによるWWL得点を減少させ,かつ総合的にオペレータの精神的作業負荷の軽減に有効であることを明らかにした。

著者

狭川 義弘 山冨 二郎

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.125, no.8, pp.409-419, 2009-08-25 (Released:2011-02-26)

参考文献数

42

---

Block caving is a most cost effective underground mining method and it is expected as a major mining method in the near future by replacing large-scale/massive open pits where a risk of slope failure and waste/ore ratio is higher as pit depth is deeper. The Northparkes Mines is well known as a pioneer of block caving mining in Australia and has ever produced copper-gold ore by using block caving from 1995. The E48 mine is the fourth block caving project in the mines and its development was started in 2006 following the block cave production in the E26 mine. The ore body can be categorised as a porphyry copper-gold deposit and the geometry is almost shaped pipe. The extraction level is located about 600m below the surface and its footprint is sized only 310m x 193m in plan, which means the E48 has very 'tall' mining zone comparing to other block caving projects in the world. The cavability has been assessed by intensive geotechnical studies based on the past experiences in the E26 mine. The extraction level is designed to maximise not only mining recovery but also productivity, taking into account stability of all the drives. Post-undercut method was selected to initiate caving and designed carefully not to damage the extraction level excessively by stress concentration and blasting. In order to improve safety, work environment, productivity and mining cost, all underground electric loaders are unmanned and to be operated remotely from the surface office by only a couple of operators.

著者

清水 隆

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.123, no.12, pp.614-619, 2007-12-25 (Released:2010-12-17)

被引用文献数

3 5

---

The Mitsubishi Naoshima Smelter & Refinery started copper smelting operation in 1917, since then has been developed smelting and refining technologies like Mitsubishi Process, which is an efficient, pollution free continuous copper smelting and converting process. At present, Naoshima Smelter & Refinery has three major activities; copper business, precious metals business and recycling business. In this decade, Naoshima Smelter & Refinery has been utilized the copper smelting technology for recycling business, which consists of the treatment of the industrial wastes and the treatment of copper and/or precious metal-bearing materials. Two recycling plants were constructed as pre-treatment plants for Mitsubishi process. One is the incinerating and melting plant, and the other is washing treatment plant for fly ash from incinerators. The treated industrial waste from these recycling plants is fed to Mitsubishi Process to recover the valuable materials and hazardous heavy metals.

著者

山下 秀 杉本 文男 山内 優 森 聡 ナムスライ デンベレル

出版者

The Mining and Materials Processing Institute of Japan

雑誌

資源と素材 (ISSN:09161740)

巻号頁・発行日

vol.113, no.11, pp.817-824, 1997

被引用文献数

4

---

In this study, drained creep tests under uni-axial compressive load were carried out on Kimachi-sandstone to clarify the creep process and mechanism of the soft sedimentary rock.<BR>During these experiments, axial strain, lateral strain and the Acoustic Emission (AE) activity were observed in the loading time intervals of several minutes to one month.<BR>Furthermore, thin sections for microscope were made of the tested specimens and micro-photographs on these sections were taken by a microscope. On these micro-photographs, using an image processing technique of a micro-computer, numerical data for the changes of pores and micro-cracks at controlled creep time or at prescribed creep region were acquired.<BR>The main results obtained from these tests are as follows; 1) In loading process of the creep load on a rock specimen, firstly the axial strain rate is shown to decrease gradually to a minimum value, after it increases gradually and finally it increases rapidly, and then the specimen is going to fail, 2) In the process of decreasing the axial strain rate, closure of pores in the rock occurs and the compacting of the rock takes place. But, the compressive strength of the specimen, which is unloaded in this loading process, is not affected by the loading time and is almost the same as that of the intact rock, 3) In the process of increasing the axial strain rate, that is after passing through the minimum point of the axial strain rate, cracks in the specimen develop toward the direction parallel to the loading axis. And also, the compressive strength of the specimen, from which load is removed in this process, decreases as compared with that of intact rock.

著者

中野 博昭 大上 悟 西野 友朗 福島 久哲 小林 繁夫

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.128, no.10_11, pp.590-595, 2012-09-25 (Released:2013-10-28)

参考文献数

15

被引用文献数

3 5

---

Electrodeposition of Cu was conducted in a synthetic electrorefining solution to investigate the effect of gelatin, thiourea and chloride ions on the polarization curve for Cu deposition, morphology, texture, surface roughness and the throwing power of the deposited Cu. In a solution containing both gelatin and chloride ions, the cathode potential for Cu deposition was significantly polarized at current densities above 200A/m2, while the thiourea depolarized the potential for Cu deposition at 200 to 1000A/m2. In a solution containing the three additives, i.e. gelatin, thiourea and chloride ions, the potential for Cu deposition was polarized at 500A/m2. It is supposed that the synergistic effect of gelatin and chloride ions on the polarization prevailed over the depolarization effect of thiourea. In the Cu deposited at initial stage, the chloride ions promoted the field-oriented texture with the orientation of direction. However, Cu deposited at initial stage from the solution containing gelatin, thiourea and chloride ions was composed of both the inclined texture type and the epitaxial growth type of crystals. The surface roughness and throwing power of the deposited Cu was most improved in the solution containing gelatin, thiourea and chloride ions, showing the synergistic effect of three additives. The thiourea had an effect on decreasing the surface roughness of the deposited Cu, and chloride ions improved the throwing power of Cu.

著者

島内 洋志 氏平 増之 鍵和田 忠男 菅原 隆之 石島 洋二 関 忠郎

出版者

The Mining and Materials Processing Institute of Japan

雑誌

資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan (ISSN:09161740)

巻号頁・発行日

vol.122, no.3, pp.119-128, 2006-03-25

---

In the transportation system using a large scaled dump truck, it is important to replace a wheel safely, quickly and easily when a wheel is burst or too much abraded partially. Conventionally, wheel replacement work has been depended on the replacement machinery for exclusive use. Considerable amount of expenditure was necessary to purchase the replacement machinery for exclusive use. Because of this reason, development of wheel replacing unit (handler unit ) has been expected for holding down the production cost.<BR>In this study, motion of a wheel replacement handler was analyzed both theoretically and experimentally, then handler unit was developed and wheel replacement test was carried out. Results obtained from the study are as follows; 1) Optional height of the axis of the large diameter wheel which is to be replaced can be adjusted easily, applying the analyzed equation obtained from theoretical study on the link motion. 2) It was found that a large scale wheel supported by a pair of steel pipes of which diameter and weight were 3.6 m and 5.2 t respectively could be rolled for setting the bolt holes to the bolt positions, when the pipe diameter was larger than 4 in. 3) As a result of rolling test for a large scale wheel using a pair of steel pipes of which diameter were 7in, it was proved that setting work of bolt holes to the bolt positions could be done within the time of 14-20 min. 4) Conclusively, it can be said that the handler unit newly developed in this study has the wide applicability, simplicity and cost performance comparing with conventional wheel replacing machinery.

著者

西松 裕一

出版者

The Mining and Materials Processing Institute of Japan

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.129, no.1, pp.1-10, 2013-01-01 (Released:2014-01-30)

参考文献数

16

---

In This paper, the author tries to discuss on the development and finiteness of natural resources on the basis of the present state of their supply and demand.The natural resources are classified into several categories i.e. mineral resource as solid raw materials, fossil fuels, nuclear power and new natural resource of energy.The finiteness and exhaustion of natural resources are one of the most important problems, in near future, because they are indispensable for production of various industrial materials as well as fuel of power plants, industrial plants, transport facilities, and home use.Then, the effect of increasing concentration of CO2 on the global warming is critically discussed from scientific and long term point of view. Furthermore, it is indicated that the nuclear power is one of the most important energy resources in the future, although there remain some severe technical problems to be solved, at present. Next, the author discuss on the technical features and possibilities of such new natural energy resources as solar panel, wind power plant, geothermal energy, etc.And, the features of various storage facilities of electric power are discussed from technical and ecological point of view, because most of new natural energy are transformed into electric power for transmission and tentative storage.Finally, the author indicates that is most important to discuss on the interaction amongst new natural energy, mineral resources, and global environment from scientific and long term point of view.

著者

高橋 雄次郎

出版者

The Mining and Materials Processing Institute of Japan

雑誌

日本鉱業会誌 (ISSN:03694194)

巻号頁・発行日

vol.17, no.197, pp.414-422, 1901

著者

板垣 乙未生 ROGHANI Ghasem FONT Jonkion M.

出版者

The Mining and Materials Processing Institute of Japan

雑誌

資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan (ISSN:09161740)

巻号頁・発行日

vol.115, no.4, pp.203-211, 1999-04-25

被引用文献数

1

---

For thermodynamically understanding copper or nickel smelting processes using oxygen or oxygen-enriched air as a blowing gas, a series of the authors' experimental studies of the phase equilibrium and distribution of minor elements between the copper matte or the nickel matte and the FeOX-SiO2 base slag under the SO2 partial pressures of 0.1, 0.5 and 1 atm at 1,300 °C are reviewed in this paper. The solubility of copper was found to be independent of pSO2 when the matte grade was specified and it was considered that this behavior was ascribable to the constancy of (pO2 /pS2 ) against pSO2 . On the other hand, it was clarified that the solubility of nickel in the slag increased with increasing pSO2 at a given matte grade. The difference in the dissolution behavior between copper and nickel was considered to be ascribable to the difference in the chemical formulas of the mono-metallic sulfides in which one copper atom combines with 1/2 sulfur atom while one nickel atom with 2/3 sulfur atom. When the distribution ratio of a minor element, X, between the slag and matte phases was defined as LXs/m = (mass % X in slag)/{mass % X in matte}, LXs/m for arsenic, antimony and bismuth at a given matte grade increased with increasing pSO2. This behavior was explained reasonabley by assuming a mutual reaction between a metallic species in the matte and an oxidic species in the slag. On the other hand, the distribution ratio of silver at a given matte grade was almost constant against pSO2. This was considered to be ascribed to the sulfidic species of AgS0.5 prevailing in the matte phase as well as the constancy of (pO2 /pS2 ) against pSO2.