AN ELECTROMAGNETIC PNEUMO CAPSULE SYSTEM FOR CONVEYING MINERALS AND MINE WASTES

Abstract

The purpose of this project is to investigate the technical and economic feasibility of using a new and advanced pneumatic capsule pipeline (PCP) system for transporting minerals and mine wastes. The new system is different from conventional PCPs in two main respects: (1) it uses linear induction motors (LIMs) instead of blowers (fans) at the inlet of the pipeline to drive (pump) the capsules and the air through the pipeline; and (2) the capsules in the PCP have steel wheels running on steel rails as opposed to capsules in conventional systems, which use wheels with rubber tires running inside a pipe without rail. The advantage of using LIM pump instead of blower is that the former is non-intrusive and hence does not block the passage of capsules, enabling the system to run continuously without having to make the capsules bypass the pump. This not only simplifies the system but also enables the system to achieve much larger cargo throughput than that of PCPs using blowers, and use of LIMs as booster pumps which enables the system to have any length or to be used for transporting cargoes over practically any distance, say even one thousand kilometers or miles. An advantage of using steel wheels rolling on steel rails instead of using rubber tires rolling inside a pipeline is that the rolling friction coefficient and hence the use of energy is greatly reduced from that of conventional PCP systems. Moreover, rails enable easy control of capsule motion, such as switching capsules to a branch line by using railroad switching equipment. The advanced PCP system studied under this project uses rectangular conduits instead of circular pipe, having cross-sectional areas of 1 m by 1 m approximately. The system can be used for various transportation distances, and it can transport up to 50 million tonnes (metric tons) of cargo annually--the throughput of the largest mines in the world. Both an aboveground and an underground system were investigated and compared. The technical feasibility of this new PCP system was determined by designing the details of the system and conducting a detail analysis of the system--both steady and unsteady analyses. Through the detailed design and analyses, it was found that no technical problem or hurdle exist that would otherwise prevent commercial use of the system today. Still, since it is a new technology, it will be prudent and advantageous to run a demonstration project before this technology is used.