The calculated distance (air line) between Sint-Katelijne-Waver and Seraing is approximately 54 miles respectively 87 kilometers.
By car or train, the actual journey to Seraing is certainly longer, as only the direct route (as the crow flies) between Sint-Katelijne-Waver and Seraing has been calculated here.
Air line (approximately)
87 kilometers
47 nautical miles