This work is a continuation and refinement of a general model developed at the Separations Research Program at The University of Texas at Austin (SRP II model) for the prediction of the height equivalent to a theoretical plate and pressure drop for distillation columns filled with metallic structured packings. It contains three parts. In the first part, the general model is briefly described and the participating equations are summarized. In the main part, the parameters needed for applying the general model for structured packings made of ceramic and plastic are presented and discussed. In the third part, we try to correct the model in order to get good predictions at low and high pressures.

Production of iron and steel is an energy-intensive manufacturing process. The goal of this study was to develop a methodology for accurately and more fairly comparing the energy-related carbon dioxide (CO2) emissions intensity of steel production in different countries and to demonstrate the application of this methodology in an analysis of the steel industry in China, Germany, Mexico, and the U.S. Our methodology addresses the industry's boundary definition, conversion factors, and industry structure. The results of our analysis show that, for the entire iron and steel production process, the base-case (2010) CO2 emissions intensity was 2148 kg CO2/tonne crude steel in China, 1708 kg CO2/tonne crude steel in Germany, 1080 kg CO2/tonne crude steel in Mexico, and 1736 kg CO2/tonne crude steel in the U.S. One of the main reasons that Mexico has the lowest CO2 emissions intensity is Mexico's large share of steel production using electric arc furnaces (EAFs) (69.4%)

Thermodynamic efficiency calculations have been performed for the separation of ternary and quaternary mixtures of hydrocarbons in both conventional and thermally coupled distillation sequences. When ternary mixtures were considered, energy savings achieved in the thermally coupled distillation sequences were between 10 and 30% in comparison to the two conventional distillation sequences. Regarding thermodynamic efficiency, thermally coupled distillation sequences presented the highest values in almost all of the cases considered. When the analysis was extended to the separation of quaternary mixtures, the thermally coupled distillation sequences show acceptable energy savings and the thermodynamic efficiency of a thermally coupled distillation sequence linked to a side stripper and a side rectifier was better than that obtained in the conventional distillation sequence; however, for the thermally coupled distillation with prefractionator (Petlyuk-type column), the second law efficiency was low when compared to that of the conventional distillation sequence for the separation of a quaternary mixture with a low content of intermediate components.