著者

秋山 友宏 八木 順一郎

出版者

社団法人日本鉄鋼協会

雑誌

鉄と鋼 (ISSN:00211575)

巻号頁・発行日

vol.74, no.12, pp.2270-2277, 1988

被引用文献数

3 14

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Exergy analysis was conducted on three ironmaking systems which were conventional ironmaking, direct reduction-electric furnace and smelting reduction systems. The exergy analysis is better than an enthalpy balance or a heat balance because exergy can express the quality of energy and evaluate different forms of energy like chemical, thermal, pressure and mixing energy by a unified measure.<BR>According to the calculated results for the specified conditions, the smelting reduction system was the lowest in net exergy loss, however, the highest in overall output exergy. The development of the efficient heat recovery process is therefore required for this system. The direct reduction-electric furnace system was the highest in net exergy loss. However, nonfired pellets were found to be effective to reduce net exergy loss. In the conventional ironmaking system, net exergy loss of its constituent processes significantly depended on the injection rate of pulverized coal and on the charging amount of nonfired pellets.

著者

名久井 恒司 能村 貴宏 秋山 友宏

出版者

公益社団法人 化学工学会

雑誌

化学工学論文集 (ISSN:0386216X)

巻号頁・発行日

vol.43, no.1, pp.63-73, 2017-01-20 (Released:2017-01-20)

参考文献数

29

被引用文献数

2

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本研究では国家プロジェクト等で開発中の水素エネルギーシステムに用いられる水素キャリアをエクセルギーにより評価する方法を提示した.水素のエネルギーキャリアとしての効率を示すために,水素長距離輸送の代表的キャリア3種(有機ケミカルハイドライド,アンモニアおよび液体水素)にその評価方法を適用し,試算した.さらに日本国内で配送する段階での形態である圧縮水素のエクセルギー損失についても考察した.これらを基にキャリアごとに,プロセスでのエクセルギー損失を水素の燃料としての化学エクセルギーに対する比で表し,類型ごとに評価した.いずれの形態でも現状技術では変換および長距離輸送の過程で水素の化学エクセルギーの約40–50%に相当するエクセルギーが失われる.さらに配送・充填の段階での損失が約17%あるので,現状の技術ではシステム全体で約半分以上のエクセルギーが失われることが判明した.プロセスから放出される未利用のエクセルギーを回収・利用により10–30%超の効率改善の可能性があり,今後水素を主要なエネルギーキャリアとするためにはその方法を実現する技術の開発が必要である.

著者

秋山 友宏 八木 順一郎

出版者

社団法人日本鉄鋼協会

雑誌

鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)

巻号頁・発行日

vol.73, no.12, 1987-09-04

著者

秋山 友宏 高橋 礼二郎 八木 順一郎

出版者

社団法人日本鉄鋼協会

雑誌

鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)

巻号頁・発行日

vol.73, no.15, pp.2108-2115, 1987-11-01

被引用文献数

2

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In order to make a clear evaluation of overall energy requirement for the production system of directly reduced iron through pellet from iron ore powders, exergy analysis was applied to the two systems. The first one consists of pelletizing, firing and reduction processes (Fired pellets method) and the second one includes pellets curing process instead of firing process (Cement bonded pellets method). Being compared with enthalpy balance, exergy analysis has two advantages in that the exergy expresses the quality of energy and evaluates different kinds of energy like chemical, thermal, pressure, mixing energies and so on by a unified measure. As a result of exergy analysis, fired pellets lose less exergy than cement bonded pellets in the reduction process in a shaft furnace. As the overall system, however, exergy requirement in the cement bonded pellets method is about 50% of that in the fired pellets method. This marked difference is caused by the large exergy loss in the firing process. Furthermore, exergy loss in the production of cement bonded pellets will be decreased by decreasing the amount of cement added as binder.

著者

秋山 友宏 八木 順一郎

出版者

社団法人日本鉄鋼協会

雑誌

鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)

巻号頁・発行日

vol.82, no.3, pp.177-184, 1996-03-01

被引用文献数

3

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The concept of zero emission of waste material in the manufacturing process has been focussed worldwide for more efficient utilization of fossil fuels and environmental protection. In this study, background and feasibility of symbiotic ironworks based on this concept were discussed from the state-of-the-art technology in catalyst and heat storage/transportation. One possibility is ironworks with methanol industry, in which charged coke is partially replaced by natural gas and the hydrogen-enriched blast furnace offgas (BFG) is used as raw material for methanol synthesis. The results of systematic analysis demonstrated that this system leads to not only exergy saving but also less emission of greenhouse gas (GHG). The key technology is to develop a catalyst for BFG of CO_2-CO-H_2 system. Another one is "urban-symbiotic ironworks", where excess outflow energy from ironworks is efficiently employed as a utility for household affairs. The use of latent heat and reaction heat is being planned in this system for thermal energy recovery and transportation. Possible energy recovery processes for the waste heat remaining in the ironmaking industry was reviewed, together with the detailed concept of 'urban-symbiotic ironworks' as an energy supplier. In particular, the use of phase change materials (PCMs) and of hydrogen storage alloy as the new technologies was fundamentally promising.