2 0 0 0 OA 堆肥発酵熱の抽出・蓄積に関する研究
- 著者
- 関 平和 小森 友明
- 出版者
- The Society of Agricultural Meteorology of Japan
- 雑誌
- 農業気象 (ISSN:00218588)
- 巻号頁・発行日
- vol.41, no.3, pp.257-264, 1985-12-10 (Released:2010-02-25)
- 参考文献数
- 8
- 被引用文献数
- 2
Experiments for extraction and accumulation of the heat generated in composting process were performed using a buried-tube-type heat exchanger and an accumulator. Water was circulated between the heat exchanger and the accumulator as a heat transfer medium. The following results were obtained.1) The compost bed maintained its average temperature at 50°C or higher for about 60 days of the whole period of composting reaction in the first stage (72 days). During this high temperature period, the experiments for heat extraction and accumulation were made by circulating water intermittently or continuously. In the case of the intermittent water-circulation, the water temperature of the accumulator attained to a designed temperature, 30°C, when the room temperature was higher than 10°C, but never did the water temperature when the room temperature was lower than 5°C. With the continuous water-circulation, the water temperature at the steady state condition was in average of 16 through 24°C.2) The apparent rate of heat generation in the compost bed was 200 through 300kcal/m3hr during an early period of about 40 days, which included a turning of the compost bed. The composting reaction was therefore not likely to be inhibited by extracting heat from the bed during the period of intermittent water-circulation experiments.3) The efficiency of heat extraction was 17-26% in the intermittent water-circulation, while the efficiency of heat collection at the steady state condition was 27-32% in the continuous water-circulation. These efficiencies could increase by the well designed arrangement and the increased number of the buried tubes.4) It is necessary to investigate the method for deciding the optimum scale or size of the container for the compost and the heat accumulator on the basis of the theoretical analysis of heat transfer processes.
1 0 0 0 OA 竹チップ発酵熱抽出・利用システムの実用化手法の開発
未利用資源の一つである竹チップの発酵過程における発生熱に着目し、伝熱理論と実験に基づいて、その熱の抽出・利用システムの適用可能性を検討した。まず、竹チップ層の発熱安定状態の発熱速度を求めた。次いで、竹チップ層内に埋設した配管への通循環通水による熱抽出の伝熱計算式を導いた。そして、抽出熱の蓄熱水槽、熱利用槽への熱供給を含めた総合システムを想定した小型システムによる伝熱実験により、伝熱計算モデルの妥当性を確かめた。さらに、実用的規模の竹チップ層を用いた発熱・蓄積・熱利用システムの実験を実施し、システムモデルの妥当性を確認した。