Triboelectrification of particulate flows on surfaces: Part I — Experiments

Abstract Triboelectrification is a ubiquitous feature of dry particulate processes. It generates hazards in many industrial systems, but is exploited in several other important applications, including electrophotographic toner charging and triboelectric separation. Unfortunately, the charging of continuous particulate flows during interaction with solid surfaces is poorly understood, and design of devices to maximise or minimize triboelectrification is usually qualitative or based on trial and error. This paper presents the results of an experimental case study of the relationship between the accumulated charge and the mechanical attributes of a particulate flow, including contact time, velocity, and the mode of contact. Silica particles of ∼ 1 mm diameter and a stainless steel slide tribocharger were used for this case study.

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