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시멘트 원료 분말의 수직 공기압수송
The Vertical Pneumatic Transport of Cement Raw Meal
HWAHAK KONGHAK, June 1982, 20(3), 207-216(10), NONE
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Abstract
수직 공기압 수송관（7.8 cm-내경 × 600 cm-높이）에서 시멘트 원료 분말(dp=23.6 μm)을 수송할 때의 기포, 난류, 고속 및 희박상 흐름 특성을 연구하였다.
공기 유속 및 입자의 순환량이 압력강하, 층의 균일성 및 기체혼합에 미치는 영향을 결정하였다.
층의 균일성을 측정키 위하여 capacitance probe를 사용하였고, 기체혼합정도를 측정키 위하여 tracer를 주입하여서 농도 변화를 높이에 따라 측정하였다.
수송속도는 공기유속과 입자순환량을 변화시켰을 때 압력강하로써 결정하였다.
본 실험에서 기포층과 난류층의 경계속도는 39 cm/sec이었고, 수송속도는 170 cm/sec로 나타났다.
난류흐름층의 균일성은 기체유속에 따라 증가하였으나 기체 역혼합도는 기체유속에 따라 감소하였다.
수직 공기 수송계의 흐름 특성을 결정키 위하여서 흐름 영역 경계도에 대한 실험식을 제시하였다.
공기 유속 및 입자의 순환량이 압력강하, 층의 균일성 및 기체혼합에 미치는 영향을 결정하였다.
층의 균일성을 측정키 위하여 capacitance probe를 사용하였고, 기체혼합정도를 측정키 위하여 tracer를 주입하여서 농도 변화를 높이에 따라 측정하였다.
수송속도는 공기유속과 입자순환량을 변화시켰을 때 압력강하로써 결정하였다.
본 실험에서 기포층과 난류층의 경계속도는 39 cm/sec이었고, 수송속도는 170 cm/sec로 나타났다.
난류흐름층의 균일성은 기체유속에 따라 증가하였으나 기체 역혼합도는 기체유속에 따라 감소하였다.
수직 공기 수송계의 흐름 특성을 결정키 위하여서 흐름 영역 경계도에 대한 실험식을 제시하였다.
The flow characteristics, the beds of bubbling, turbulent, fast and dilute phase, have been studied in a vertical transport line（7.8 cm-ID × 600 cm-height）. The cement raw meals have been transported by compressed air at various flow regimes.
The effects of gas velocity and solid circulating rate on the pressure drop, bed homogeneity and gas backmixing have been determined by measuring the fluctuations of pressure drop.
Capacitance probe has been employed in order to measure the bed homogeneity. The degree of backmixing was measured using tracer injection technique. The transport velocity has been determined from the data of pressure drop at various air and particle circulation rates.
From the present study, the slug breakdown and transport velocities have been found to be 39 and 170 cm/sec, respectively. The bed homogeneity of turbulent bed increased with gas velocity. However, the extent of gas backmixing decreased with increasing gas rates in the turbulent beds.
Equations were proposed in order to construct a flow regime diagram in the vertical transport line.
The effects of gas velocity and solid circulating rate on the pressure drop, bed homogeneity and gas backmixing have been determined by measuring the fluctuations of pressure drop.
Capacitance probe has been employed in order to measure the bed homogeneity. The degree of backmixing was measured using tracer injection technique. The transport velocity has been determined from the data of pressure drop at various air and particle circulation rates.
From the present study, the slug breakdown and transport velocities have been found to be 39 and 170 cm/sec, respectively. The bed homogeneity of turbulent bed increased with gas velocity. However, the extent of gas backmixing decreased with increasing gas rates in the turbulent beds.
Equations were proposed in order to construct a flow regime diagram in the vertical transport line.
