Abstract:
With the development of coal chemical industry, efficient and clean transportation of the coal has become a real research subject. Using pipelines to convey high concentration coal-water slurry has obvious advantages, such as less investment, energy saving and environmental protection. Research on the resistance characteristics of the coal-water slurry is of great significance to the conveying experiment design. Because small-diameter pipe experiment is more convenient to operate and save more materials, the small-diameter pipe is often used for simulation in the laboratory. The flow characteristics of high concentration coal-water slurry with the mass concentrations of 53% and 58% in the pipes with a diameter of 50, 47, 32, and 29 mm were tested in this study. The formula of rheological parameters for different flow regimes under the slip condition is derived, and the resistance coefficients of the coal-water slurry are obtained based on the analysis of the slip efficiency. The resistance of high concentration coal-water slurry is calculated using the calculation formula of homogeneous flow resistance. Compared with other formulas, the homogeneous flow formula is most consistent with the experimental results. The calculated results show that the rheological model of CWS conforms to the Herschel-Bulkey model. Under the conditions of the sliding effects, the relationship between the resistance coefficients of the high concentration coal-water slurry and the generalized Reynolds number can be expressed as a formula, and the resistance can be calculated by the homogeneous flow formula.