MEASUREMENT OF SOLID VELOCITY IN THE VERTICAL PNEUMATIC TRANSPORT OF POWDERY MATERIAL AT A HIGH SOLID-LOADING RATIO

In the pneumatic transport of PVC powder whose mean diameter and material density are 134 mu m and 1330 kg/m**3, respectively, the solid velocity is measured by the 'activable' tracers method, whereby tracers can be activated when required, in a vertical line 100. 0 mm in inside diameter and 24 m in length, when the air velocity is changed from 16. 5 m/s to 28. 9 m/s and the solid-loading ratio between 48. 8 and 82. 5. The used nuclide was **5**6Mn or **8**2Br. The pipe friction factor for the solid phase was also obtained for the same conditions. The present method is applicable to measurements at high solid-loading ratios.