A fluidized bed system combining two circulating fluidized bed reactors is proposed and investigated for chemical looping combustion using metal oxides as oxygen carriers. The global solids loop starts in one of the two reactors (primary reactor) where solids are entrained, separated from the gas in a cyclone and sent to the other reactor (secondary reactor) via a fluidized loop seal. From the ...

This is the first in a series of three papers describing combustion of biosolids in a 5-kW bubbling fluidized bed, the ash chemistry, and possible application of the ash produced as a fertilizing agent. This part of the study aims to clarify whether the distribution of main ash forming elements from biosolids can be changed by modifying the fuel matrix, the crystalline compounds of which can be...

In present paper, dynamic behavior and control of a fluidized bed reactor for polyethylene production has been considered. A double active sites model for Ziegler-Natta catalysts is used for simulation of polymerization reaction. Hydrodynamic behavior of the bed is modeled using a two phase model including bubble and emulsion phases in which bubble phase has plug flow pattern with different...

Victorian lignites (brown coals) in Australia have long been the mainstay of the Victorian economy, providing low-cost electricity to the state. In order to secure energy supplies for the future and to reduce the environmental impacts of power generation using the lignites, the Cooperative Research Centre (CRC) for Clean Power from Lignite is developing an Advanced Pressurized Fluidized-Bed Com...

A pilot-scale fluidized bed reactor was built and used to study and gain a better understanding of the propylene polymerization process at conditions similar to those of industrial fluidized-bed reactors. Propylene polymerization reaction was carried out continuously in the reactor and dynamic temperatures, and propylene and hydrogen concentrations data were collected. Simulated dynamic profile...

Effects of different system parameters on the hydrodynamic behavior of a cold-model fluidized bed gasifier have been studied. Correlations developed for the Equivalence Ratio and Euler’s number on the basis of regression analysis have been validated by using the MATLAB coding. Comparison of calculated values of Equivalence ratio and Euler number against the experimentally observed values gives ...

This work presents a computational study of flow behaviour in a bubbling fluidized bed polymerization reactor. The model is developed by using the commercial CFD code Fluent 6.3. The model is based on an Eulerian description of the gas and the particle phase. The effect of distributor shape on fluidization is analyzed using the inbuilt Gidaspow and Syamlal-O’brien Drag Model. The computational ...

A process for lignin removal from alkaline pulping liquors (black liquors) has been developed within the FRAM2 R&D Program (Future Resource Adapted Pulp Mill, part 2). The lignin product (Fig. 1) from a demonstration plant, owned and operated by Innventia (formerly STFI-Packforsk), was characterized and used in different combustion trials with good results – co-firing of lignin and bark in a fl...