Tao T.Peng X.F.Lee D.J.2019-05-142019-05-14200607373937https://scholars.lib.ntu.edu.tw/handle/123456789/408025This work utilized an X-ray micro-computerized tomography scanner (micro-CT) to investigate how skin layers - hard and relatively impermeable layers that hinder mass transfer - form and develop on wastewater sludge cake with (cake-O) or without artificial cracks (cake-N). A novel scheme that applies Otsu's algorithm twice was employed to determine the solid phase and skin layers in the scanned cake images. Initial cracks in a cake had significant impact on how the skin layer would form on the cake. A unique correlation between effective surface area to drying (not covered by a skin layer) and moisture content was identified. The advancement velocities of skin layers on drying cake were evaluated.DryingImage analysisSkin layerSludge[SDGs]SDG11journal article10.1080/073739306007762582-s2.0-33746495622https://www.scopus.com/inward/record.uri?eid=2-s2.0-33746495622&doi=10.1080%2f07373930600776258&partnerID=40&md5=6feaa4f63dd4263a997f557fad8f9662