Determination of density and classification of post-coagulation sediment

The coagulation process is one of the water and wastewater treatment processes. It results in the precipitation of sediment. After the coagulation process, the density of the sediment has a significant impact on the sedimentation rate of particles. These particles have different shapes, sizes and structures, and they settle in a different way. The particle density has an impact on the settling rate. The structure of particles results in two types of pores. Micropores are characteristic features of the sediment, but macropores should not be considered while determining the density. In this paper sediment samples were prepared and the density was determined using the gravimetric method by means of the press. The number of press strokes should not destroy the microstructure of sediment. The authors determined the degree of sample compression to minimize errors while determining the density. The volume of samples was obtained using X-ray tomography and image processing. The correct determination of the sample volume depends on the correct number of the threshold. Image processing was performed using LabVIEW software and Vision module. The paper presents the statistic classification of post-coagulation particles and the results of tests.