著者

所 千晴

出版者

ホソカワミクロン株式会社

雑誌

粉砕 (ISSN:04299051)

巻号頁・発行日

vol.66, pp.13-20, 2022-12-15 (Released:2022-12-15)

参考文献数

14

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SDGsそしてカーボンニュートラル時代を迎え,サーキュラー・エコノミーをはじめとする資源循環型社会構築に対する社会の関心はますます高まっている。資源循環のための粉体プロセス技術には,物理的,物理化学的,化学的な種々の分離技術が存在するが,いずれも省エネルギーかつ省資源という大きな制約を満たすことが大前提であり,カーボンニュートラルなどの環境負荷低減と資源循環との両立のために,サーキュラー・エコノミーのような多重資源循環ループを支える多様な分離技術開発が必要とされている。本稿ではそのような取り組み例として,カーボンニュートラル促進による需要の指数関数的な増加が見込まれるリチウムイオン電池に対し,サーキュラー・エコノミーの概念図にある一番外側のリサイクル技術開発と,その内側の正極活物質粒子ダイレクトリサイクル技術開発の例を紹介した。

著者

辰本 拓也 綱澤 有輝 小板 丈敏 高谷 雄太郎 小山 恵史 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.139, no.11_12, pp.52-62, 2023-12-29 (Released:2023-12-27)

参考文献数

18

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To clarify the mechanism of liberation in the comminution process of electronic scrap (e-scrap), we attempted to express the degree of liberation by first-order kinetic equation related to impact energy. Breakage energy measurements, comminution experiments, and discrete element method (DEM) simulations were conducted on two types of e-scrap with relatively simple structures. The mechanism of the liberation was estimated from the observation of the fractions in the comminution experiments. The results of the breakage energy measurements and DEM simulations supported the mechanism in terms of impact energy. The results of fitting first-order kinetic equations based on the cumulative specific impact energy from the DEM simulations and the degree of liberation in the experiments showed a high correlation. The fitting parameters of the firstorder kinetic equations were compared confirmed to be consistent with the mechanism of liberation and the breakage energy measurements, suggesting the numerical validity of the equations. In conclusion, it was shown that for e-scrap with relatively simple structures, the first-order kinetic equations of the cumulative specific impact energy calculated by DEM simulations can be used to evaluate the degree of liberation.

著者

所 千晴

出版者

一般社団法人 廃棄物資源循環学会

雑誌

廃棄物資源循環学会誌 (ISSN:18835864)

巻号頁・発行日

vol.33, no.3, pp.181-187, 2022-05-31 (Released:2023-05-31)

参考文献数

20

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使用済みリチウムイオン電池からコバルト,ニッケル,銅等を回収するための分離プロセスを概観した。現在リサイクルプロセスの主流となりつつある焙焼プロセスが,安全上,また分離の効率上,重要な役割を果たしていることを示した。さらに,粉砕や物理選別からなる物理的分離プロセスによって,ブラックマスと呼ばれる正極活物質と,銅,鉄,アルミニウムに分離され,分離された正極活物質はさらに酸浸出や溶媒抽出によってコバルトやニッケルに分離されるフローを紹介した。また,サーキュラー・エコノミーの概念にもあるように,内側の資源循環ループを創成すべく焙焼なしの分離プロセスが検討されていることを紹介するとともに,筆者らが取り組んでいる電気パルス法によるアルミニウムと正極活物質粒子との分離技術開発を紹介した。

著者

淵田 茂司 田嶋 翔太 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.138, no.11, pp.160-169, 2022-11-30 (Released:2022-11-25)

参考文献数

24

被引用文献数

1

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This study examined effective removal methods for high amounts of manganese (Mn) and zinc (Zn) in acid mine drainage (AMD) by addition of different neutralizing agents (NaOH and NaClO) and synthesized birnessite (δ-MnO2) using two-type AMD samples which Mn and Zn concentrations were 778 and 410 mg L−1 for A mine and 18.0 and 5.51 mg L−1 for B mines, respectively. The precipitation mechanism of these metal ions was investigated by geochemical modeling (PHREEQC) and X-ray absorption near edge structure (XANES) analysis. Mn concentrations were below the effluent standard (10 mg L−1) at pH 9–10 with the NaOH neutralization, whereas it was accomplished at lower pH (6–7) condition with the NaClO addition; it could act as an oxidizing agent, resulting that most of Mn precipitated as δ-MnO2. Zn concentrations decreased below the effluent standard (2 mg L−1) at pH 8–9 using both neutralizing agents. XANES analysis results indicated Zn was removed by the surface complexation formation on manganite and δ-MnO2 surface. More effective removal of Mn and Zn from AMD was found around pH 6 when a sufficient amount of δ-MnO2 was added to both AMD before the NaOH neutralization; a geochemical model coupling charge distribution multisite ion complexation revealed the triple-corner-sharing on δ-MnO2 was the most reasonable mechanism. Our result suggests that the presence of sufficient δ-MnO2 was the most effective for high Mn and Zn contents AMD treatment; however, ferrous ion (Fe2+) can inhibit the adsorption reaction and decompose δ-MnO2. Thus, pre-precipitation of Fe2+ is required to enhance the effect of δ-MnO2 on Mn and Zn removals from AMD.

著者

綱澤 有輝 古作 吉宏 坂入 義隆 塚田 浩二 斉藤 瑞稀 蛭子 陽介 三觜 幸平 陳 友晴 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.138, no.6, pp.95-102, 2022-06-30 (Released:2022-06-30)

参考文献数

14

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The high-pressure grinding roll (HPGR) has been known to achieve a high mineral liberation with relatively low energy consumption. However, quantitative methods for evaluating the effect of HPGR grinding on the promotion of the mineral liberation of copper ores have not been fully established. This study aims to establish a quantitative evaluation of promoting the liberation ratio of copper minerals by HPGR grinding. We performed clack observation using the combination of the paint penetration method and the mineral liberation analyzer (MLA). Direct clack observation reveals that HPGR grinding can promote the formation of cracks in the product particles. The liberation ratio of copper minerals is related to the percentage of cracks in the product particles. Besides, the grinding tests using a laboratory ultra-small scale showed that the liberation ratio of copper minerals became larger than that of the ball milling alone. In all conditions where HPGR grinding was conducted before ball milling, the ball milling time became almost half that of the ball milling alone. The grinding kinetic constant of the HPGR milling product in ball milling is also determined. The grinding kinetic constants for 80% passing particle size in HPGR grinding products are larger than that in feed ores, and they are consistent with the trend of ball milling time. This might be because the HPGR milling causes cracks in the particles, which are more easily ground in the subsequent ball milling. Consequently, this study demonstrates that the ratio of clacks and the grinding kinetic constant in the ball milling process after HPGR milling can be used as an index to quantitatively evaluate the effect of HPGR milling on promoting the liberation of copper minerals.

著者

松岡 秀和 三觜 幸平 河田 真伸 高谷 雄太郎 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.138, no.2, pp.12-18, 2022-02-28 (Released:2022-02-10)

参考文献数

31

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Copper sulfide minerals are the major raw materials for copper products. Copper sulfide minerals are mined at copper mines and concentrated by flotation process. In recent years, the mining of refractory copper ores, which is difficult to concentrate by flotation due to their fine grain size, presence of multiple copper mineral species, and fluctuation of the content ratio of these minerals in feed ore. In addition, the hydrophilization of copper mineral surfaces due to oxidation and the mineral content variation of ore result in poor and unpredictable performance of flotation operation. In this study, therefore, we focused on the activation of the copper mineral surfaces using sodium hydrosulfide (NaHS) to render the surfaces hydrophobic and tried to quantify the effect of the fluctuation of mineral content ratio by using a new flotation kinetic model. Two samples showing different content ratios of chalcocite, bornite, and chalcopyrite and having fully oxidized surface were used in the flotation tests. We established a new flotation kinetic model by considering the reaction between the copper mineral surface and NaHS and the depression of floatability by adsorption of hydrogen sulfide ions onto the copper mineral surface. As a result, a good relation was confirmed between the model and the flotation test results for both ore samples. This result showed that our model can accurately predict the flotation results of refractory copper ores and will encourage the further usage of these refractory copper ores in the future.

著者

髙谷 雄太郎 淵田 茂司 濱井 昂弥 堀内 健吾 正木 悠聖 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.138, no.2, pp.19-27, 2022-02-28 (Released:2022-02-26)

参考文献数

42

被引用文献数

3

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In decades, various studies on passive treatment methods of acid mine drainage (AMD) have been actively conducted in order to reduce the cost of AMD treatment. Open limestone channel is one of the most common methods and has already been implemented mainly in overseas. On the other hand, it is difficult to secure large channels in Japan due to its topography, we need to consider the use of alkaline materials with higher acid neutralization potential which enables successful treatment with narrower space. In this study, therefore, PAdeCS, a cement-derived environmental remediation agent, was used to remove the harmful metal elements by neutralization treatment. Then, we developed a simulation model assuming a combined system of open limestone channel and alkaline material (PAdeCS) channel and predicted the behavior of harmful metal elements within the combined channel. The simulation results showed that PAdeCS has extremely high acid neutralization potential, that high temperature is advantageous for neutralization treatment of harmful metal elements, and that the channel design needs to be changed depending on the initial drainage composition. Finally, a new flowchart for selecting the appropriate passive treatment method was proposed, which consists of three steps of the preferential removal of Fe, neutralization by limestone, and additional treatments.

著者

淵田 茂司 門倉 正和 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.137, no.12, pp.116-122, 2021-12-25 (Released:2021-12-25)

参考文献数

15

被引用文献数

2

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Acid mine drainage (AMD) generation is a serious problem from the environmental and economic perspectives, because it contains a large amount of heavy metals and because there are high costs associated with maintaining the facilities, purchasing neutralizing agents, and disposing sludges; which are required for the treatment process. In this study, changes in AMD quantity and quality for the next decades were predicted by a three series tank model in three stages, by combining the first order kinetic calculation of sulfide minerals' dissolution for two metal mines (X and Y) in Japan. Results from the AMD quality model represented the decrease of heavy metal concentrations below the effluent standard values in 30–140 years, by considering dilution and/or additional dissolution by heavy rain and snow melting, although these predicted values diverged by our previous model. However, the low correlation coefficient values (0.23–0.63) observed between the measured values of heavy metal concentration and the values calculated by our new model, mean that other chemical reactions, such as sulfate and/or carbonate mineral dissolution could greatly affect the AMD quality. In fact, there was no correlation between the metal potential calculated by our model and the real distribution of sulfide minerals at X mine. Our results therefore indicate that specific geochemical reaction and geological information should be included in the AMD quality prediction model, to estimate more accurately the fluctuation of each heavy metal concentration during different seasons.

著者

大和田 秀二 所 千晴

出版者

早稲田大学

雑誌

挑戦的萌芽研究

巻号頁・発行日

2012-04-01

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CO2を飽和させた硫酸溶液に、硫酸第一鉄と過酸化水素、pH調整剤を少しずつ断続的に添加させることによって高効率にラジカルを発生させる高効率フェントン法を用いて、CO2をメタノールやエタノールへ変換させることに成功した。中間生成物として、ギ酸、酢酸、シュウ酸、ホルムアルデヒド、アセトアルデヒドが生成することがわかった。また、各種触媒の使用や、プロセス条件の最適化によって収率が向上した。さらに、フェントン反応の結果生じる汚泥は水酸化第二鉄とシュベルトマナイトの混合物であるが、水酸化第二鉄の割合が大きくなるようにプロセス条件を制御することによって、アルコール生成の収率が向上することがわかった。

著者

加藤 達也 福島 諒 佐藤 康市 山縣 三郎 所 千晴

出版者

一般社団法人 資源・素材学会

雑誌

Journal of MMIJ (ISSN:18816118)

巻号頁・発行日

vol.136, no.12, pp.151-158, 2020-12-31 (Released:2020-12-25)

参考文献数

51

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The objective of this study is to clarify the zinc removal mechanism and construct a quantitative model for column experiments using a natural component of organic soils, namely leaf mold. We performed column experiments using actual acid mine drainage (AMD) at several conditions. After column experiments, the residues in the column were analyzed by x-ray absorption fine structure (XAFS) analysis. These experimental results highlighted that when leaf mold, limestone, and iron powder were filled in the column, the zinc removal mechanism was not only surface complexation for leaf mold but also the formation of zinc sulfide. Whereas, when only leaf mold was filled in the column, that was only surface complexation for leaf mold. Based on the above results, we constructed a quantitative model incorporating surface complexation by leaf mold, sulfate reduction reaction by sulfate-reducing bacteria, Fe2+ dissolved reaction from leaf mold, and one-dimensional transport against the height of the column. The experimental results of pH and the concentration of each element were successfully represented by the quantitative model.