LOCALLY FLUIDIZING FEEDER FOR POWDER TRANSPORT

Solid fuel delivery systems form an essential component of laboratory type experimental apparatus. In the past feeders have been developed for feeding coal particles. They include: bed fluidized feeder (BFF), syringe feeder and spouted bed feeders. A new feeder called locally fluidizing feeder (LFF) has been developed. The LFF involves only local fluidization around the off-take rather than the fluidization of the whole bed. Two types of feeders were developed: (i) small scale LFF and (ii) large scale LFF. The small scale LFF is capable of delivering 0.5 to 30 g min-1. Feeder performance has been evaluated for the three different solids: sand, char and coal. A simple theoretical analysis has been carried out for predicting the performance of the small scale LFF and the results are compared with the experimental data. A large scale LFF is then designed for transporting sand in the range of 200-1000 g min-1, from a mound and the performance is again compared with the predictions.