著者

飯島 伸介 中山 勝也 西村 育夫 霜田 浩 片桐 猛

出版者

公益社団法人 日本鋳造工学会

雑誌

鋳造工学 (ISSN:13420429)

巻号頁・発行日

vol.82, no.1, pp.29-37, 2010-01-25 (Released:2015-04-21)

参考文献数

27

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In the present work, a real plant of a regenerative thermal oxidizer (RTO) was applied to treat odor constituents from shell mould castings. As a result, it was found that concentrations of ammonia were about 20ppm, which is higher than that of other odor constituents in exhaust gas from shell mould castings. However, o- and p- cresol contained in the exhaust gas were found to highly contribute to offensive odor more than ammonia due to their low olfactory threshold, and the odor index of the exhausted gas was 40.   As a result of the treatment of the exhausted gas by the RTO, about 99.7% and 99.5% of the o- and p- cresol was decomposed, and the odor index of treated gas decreased from 40 to 21, which is lower than the regulation value in the offensive odor control act. Thus, it can be concluded that the RTO is suitable for decreasing odor constituents from shell mould castings.   The material balance of the RTO used for the real plant was calculated by using average values of operating data for 24hours. As a result, 92.4% of thermal efficiency was obtained, which results in higher energy savings than that of typical combustion processes.   In order to prevent tar adhesion which contributes to offensive odor and to the obstruction of regenerative heat exchanger in the RTO, a stainless filter and pre-heating system were introduced to the RTO. As a result, it was found that pressure loss of the RTO was almost the same as 1.8kPa for 400h. Subsequently, the regenerative heat exchanger was heated up to 623K by means of baking treatment, and it was found that tar was more or less completely removed from ceramic honeycombs in the regenerative heat exchanger.