Enhanced Productivity of Chemical Processes Using Dense Fluidized Beds

Abstract

Executive SummaryDense gas-solid reactors are used throughout the chemical industry for catalytic reaction processes including hydrocarbon cracking, Fischer-Tropsch synthesis, and production of titanium dioxide, polyethylene, and many other chemicals. In addition, fluidized beds are used for non-catalytic reaction processes including chlorination, oxidation, roasting, calcinations, combustion, incineration, heat treatment, coatings, and many others. However, understanding, control, and scale-up of these processes are limited by difficulties in measurement and modeling the dense solid-particle flow. Millennium Inorganic Chemicals, Inc. (MIC) and ExxonMobil Research and Engineering (EMRE), and Sandia National Laboratories (SNL) formed a multidisciplinary team with CPFD Software, LLC (CPFD), to conduct a three-year research program to provide advanced analysis capability in solid-fluid reactors, with broad extensions to catalysis, thermal cracking, gas-solid separation, and solid chemistry. This project focused specifically on chemical issues in fluidized-bed applications. The direct application is the chemistry in ExxonMobil's Fluid Coking™ processes and in the MIC titanium tetrachloride production pricess, but this development has broader benefits through the ability to better predict and control flow and chemistry in dense gas-solid reactors.The work performed under this DOE grant focused on the Technology Vision 2020: This work relates to Reactions and Particulate Processes, specifically within Technology Area 1 -Chemical Synthesis.The work completed under this grant addresses Enabling Technologies within Computational Technology by integrating a "breakthrough" particle-fluid computational technology into traditional Process Science and Engineering Technology. The work completed under this DOE grant addresses five major development areas 1) gas chemistry in dense fluidized beds 2) thermal cracking of liquid film on solids producing gas products 3) liquid injection in a fluidized bed with particle-to-particle liquid film transport 4) solid-gas chemistry and 5) first level validation of models. Because of the nature of the research using tightly coupled solids and fluid phases with a Lagrangian description of the solids and continuum description of fluid, the work provides ground-breaking advances in reactor prediction capability.The advanced computational models for chemistry and liquid-jet for reactor design and operation was implemented in the commercial computational particle fluid dynamics (CPFD) package (Barracuda™). This report includes five topical reports with the first four describing the chemistry and liquid jet functionality and where possible compares calculations with experimental data. The final report outlines some of the experiments that were performed as well as proposed experiments that had to be postponed or eliminated due to funding restrictions. In addition, the report outlines the steps taken to commercialize the product arising from this joint effort. ENHANCED PRODUCTIVITY OF CHEMICAL PROC...