Introduction

In a variety of industries, bulk materials are processed, refined, or handled in some form. These solids must be fed to individual process steps, introduced into them, removed after treatment, and transported to the next processing step. Along such a process chain, the properties of the bulk material, e.g., its grain size or grain size distribution, and thus its handling behavior can change significantly. Transports between the various process steps generally take place at ambient pressure. However, deviating pressure levels in individual process stages are also possible. Example: Feeding fine coal against pressures of approx. 6 bar(g) into the wind box of a blast furnace. The temperatures of the bulk materials can reach up to approx. 500 °C, depending on the process. Typical in-plant conveying distances range from a few meters to the kilometer range. In this context, solid mass flows of a few kg/h up to several 100 t/h must be managed. The particle sizes of the goods to be transported can cover the range from a few micrometers to several centimeters, with a tendency towards increasingly finer-grained products being noticeable. According to the indicated requirements, the transport, entry, and discharge systems to be used in the current process must be planned and selected. Chapter 1 contains a detailed comparison of pneumatic and mechanical conveying methods.