A vertical freezing test on sewage sludge is conducted in this work. The sludge is placed in sample tubes immersed vertically into a freezing pool, whence the ice front grows upwards at a constant freezing speed. If the sludge is completely frozen, regardless of the freezing speed, the sludge filterability is markedly improved. However, the associated sludge settleability and the final sediment height will not alter much except when gross migration of flocs takes place.

This content is only available as a PDF.