Flow Characteristics of Coal-Water Mixtures. Final Report, September 1, 1981-September 30, 1984

摘要

Coal water mixtures have been transported in a recirculating test loop facility. A complete description of the test facility is given. Details of slurry preparation and handling procedures, as well as test procedures, are presented. Test results that examine additive effectiveness and effects of slurry age are discussed. Parametrization tests were conducted on temperature, particle size distribution, concentration, coal type, and pipe diameter. Metzner-Reed coefficients were calculated for the different concentrations and particle size distributions. During this series, different commercial instrumentation was tested for reliability with coal-water slurries. Tests were conducted at different pH values to quantify the effect of pH on pressure drop. Transient behavior was studied during step changes in the mass flow rate. Visualization of flow patterns in bends and elbows was studied using slurries prepared with a white vinyl powder. Three commercially available slurries and two mixes under commercial development were tested. Handling and transport problems are discussed. Several of the classical correlations were applied to the data with limited success. A modeling approach developed for horizontal turbulent flow was modified for laminar flow. Results of this effort show an improvement over classical methods. Correlations for homogeneous flow around bends and elbows are modified for slurries. 16 refs., 38 figs., 8 tabs. (ERA citation 11:010912)