Pressure loss characteristics and calculation model of calcium carbide sludge flow in a pipe

Calcium carbide sludge is a kind of dense paste; when transported by pipeline, the pressure loss is enormous. However, how to calculate the pressure loss accurately has not been solved until now. This article aims to present a new method to build a pressure loss calculation model based on the experimental data of pipeline transportation. To determine the relationship between the pressure loss and the properties of calcium carbide sludge, a new circulating pipeline testing apparatus was designed. The test studied pressure losses arising from changes in the mass concentration of the paste, flow velocity, pipe diameter, and pipe length. Analyzing the obtained data by means of nonlinear curve fitting, the adsorption coefficient and viscosity coefficient were defined and then the calculation formula was deduced. Finally, the calculation formula was verified for a project pipeline with a relatively large diameter equal to phi 200 mm and the same parameters as those of industrial applications. The results show that under the appropriate conditions of applying the model, the relative error is less than 20%, so the model can be applied to engineering pressure loss estimation. This method provides a suitable pipe transportation calculation method for dense paste, combining experimental data and theoretical derivation.