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A large number of particles with small size and light density in mine water are difficult to remove by traditional separation equipment. In order to improve the efficiency of mine water treatment, a cone-plate clarifier is proposed in this paper. The particle size distribution and their fragmentation fractal dimension were studied in 15 sampling points of the cone-plate clarifier to elucidate the process of floc growth and settling. The influence of the tangential inlet velocity size distribution characteristics was also studied. The results showed that the cone-plate clarifier can effectively improve suspended solids and turbidity removal efficiency. The floc growth and settlement courses are shown in the charts. The cone-plate clarifier was divided into four zones: micro flocculation, floc growing, settlement, and exit pipe. Because the fluid enters the cone-plate clarifier tangentially, the value of the inlet velocity and the tangential velocity are equal at the inlet feed. With the increase in tangential velocity, the flocculation efficiency first increased and then decreased. Comprehensive analysis of the particle greater than 50 µm in the effluent showed that the optimal inlet was qual to 1.63 m/s. By fitting the equations, the optimal SS and turbidity removal efficiency reached the maximum values of 92.04% and 80.18% at the inlet velocity of 1.86 m/s and 1.77 m/s, respectively. [ABSTRACT FROM AUTHOR]

The changes of soil particle size distributions (PSDs) can be used as a proxy for soil development intensity and an indicator of soil formation processes. The fragmentation fractal dimensions can describe PSDs of soils in a single parameter. The objective of this research is to use mass-based fragmentation fractal dimension models to describe PSDs and evaluate the relationship between the fragmentation fractal dimension values (D F ) and pedogenesis in loess-paleosol. Based on the theory of fragmentation fractal dimension, particle size data from 837 eolian loess samples from the lower part of Chaoyang section uniform loess deposits were analyzed with mass-based models using linear regression and piecewise linear regression. A single power-law exponent can characterize the PSDs across the domain of 0.1–54.4 μm. The trend of fragmentation fractal dimension values is consistent with chemical weathering indices, magnetic susceptibility, and <1 μm clay contents. The D F value of PSDs can be used to assess the degree of particle fragmentation and intensity of pedogenesis for loess-paleosols. A paleosol has a greater D F value than a loess; indicating that the greater the D F value, the greater the effect of energy events that have occurred. Loess particles in paleosols were fragmented to finer particles with an average median grain size (φ = 6.21 ± 0.24, CV = 3.94%) and were poorly sorted to very poorly sorted (So = 1.922 ± 0.128) due to strong pedogenesis under a prominent warm-wet climate. In contrast, particles in loess experienced fewer fragmentations and had a greater average median grain size (φ = 5.89 ± 0.35, CV = 5.89%) due to weak pedogenesis under prominent cold-dry climate. These results confirm the use of fractal characteristics to reflect the loess particle size reduction process. Two domains within the 0.1–54.4 μm domain, F1 and F2, were identified where power-law scaling was applicable. The close transition point from F1 to F2 is 7.64 ± 1.21 μm. The fragmentation fractal dimensions of the two domains decreased in the order: D F1 (close to 3) > D F2 (close to 2). The energy dissipation for fragmenting larger particles from coarse silt (CSI) to fine silt (FSI) is identified in the volume and for fragmenting smaller particles from fine silt (FSI) to clay (CL) it is substantially on the surface. This research indicated that fragmentation fractal model is a good descriptor for the PSDs and D F can be a value quantifying the intensity of loess-paleosol pedogenesis. [ABSTRACT FROM AUTHOR]