Gotowa bibliografia na temat „Gas-liquid distribution three phase monolith reactors”

This paper presents a unified model that inter-relates gas flow rate, liquid flow rate, and hold-ups of each of the liquid, gas, and solid phases in three-phase, fluidized-bed biofilm (TPFBB) process. It describes how carrier properties, biofilm properties, and gas and liquid flow velocities control the system dynamics, which ultimately will affect the density, thickness, and distribution of the biofilm. The paper describes the development of the mathematical model to correlate the effects of gas flow rate, liquid flow rate, solid concentration, and biofilm thickness and density. This knowledg

Scientists require methods to monitor the distribution of gas bubbles in gas-liquid bubble column reactors. One non-destructive method that can potential satisfy this requirement in industrial situations is ultrasonic transmission tomography (UTT). In this paper, an ultrasonic transmission tomography sensor is designed for measuring bubble distribution in a reactor. Factors that influence the transducer design include transmission energy loss, the resonance characteristics and vibration modes of the transducer, and diffusion angles of the transducers, which are discussed. For practical applica

Increasing volumes of wastewater combined with limited space availability and progressively tightening European standards promote the development of new intensive biotechnologies for water treatment. Fixed biomass processes offer several advantages compared with conventional biological treatments: higher volumetric load, increased process stability and compactness of the reactors. The purpose of this paper is to present a new concept of gas-lift mobile bed, the circulating floating bed reactor (CFBR). The reactor design is simple and does not require any complex technical devices (easier efflu

Two-phase flow characteristics in vertical capillary downflow were investigated in order to obtain understanding of the behaviour of three-phase monolith reactors. Experiments were conducted using air and dyed water in round and square capillary tubes of 2 mm and 3 mm diameter. The flow regimes and transitions observed were recorded using high speed videography and this data was used to produce flow maps for each tube. The gas and liquid superficial velocities used ranged from 0.001 to 10 m/s and 0.0001 to 1 m/s respectively. The flow regimes and their transitions were found to be a strong fun

The objective of this work was to investigate the relative contribution of the convective and dispersive mixing mechanisms to the overall solid phase mixing mechanism for three-phase fluidized bed reactors. Noninvasive Radioactive Particle Tracking (RPT) data were obtained at various operating conditions, reactor diameters and particle systems. The structural wake model was updated and consists of three sub-phases: the particle wake and downflow-emulsion phase following the convective mixing mechanism and the vortex-emulsion phase following the dispersive mixing mechanism.The particle velocity

Chemical engineering aims, on the one hand, at simulating and predicting phenomena with respect to chemical reactions, such as intrinsic reaction kinetics, mass transport, sorption effects, thermodynamic and hydrodynamic phenomena and, on the other hand, at the design, construction, and optimization of the corresponding reactors in which these reactions are performed. The present chapter starts with explaining how intrinsic reaction rates of chemical transformations occurring on a heterogeneous catalyst surface may be disguised by mass and heat transfer phenomena and how the occurrence of such limitations can be diagnosed. Subsequently, adsorption phenomena are described and it is explained how to account for them in a kinetic model. The third section of this chapter comprises a strategy to extrapolate gas phase kinetics towards liquid or three-phase reactions envisaging the up-scaling from ideal laboratory scale conditions to realistic commercial applications. Next, the focus moves from reaction towards reactor engineering. First, the traditional reactor types, i.e., batch, semi-batch, plug flow, and continuous stirred tank reactors, are discussed. Subsequently, microreactors, which are characterized by a much larger surface-to-volume ratio and, hence, exhibit an enhanced mass and heat transfer, are discussed. Finally, various methods of energy input are reported. Some specific reactor types such as monolith and membrane reactors, which are able to dramatically decrease the pressure drop, are discussed in more detail in the fifth section. The final section of this chapter aims at reactor and process design. It starts with a discussion on the hierarchical design strategy of chemical processes. Subsequently, reactor selection based on the specific boundaries of the indented application is addressed. The chapter wraps up with a discussion on the phenomena that should be accounted for while designing the selected reactor, i.e., capillary condensation, the catalyst wetting efficiency, the flow regime, and axial and radial dispersion.