Flow regime diagram for vertical pneumatic conveying and fluidized bed systems

Rabinovich, Evgeny; Kalman, Haim

doi:10.1016/j.powtec.2010.10.017

Cited by 76 publications

(28 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…With a minimum of two calculated dimensionless similarity numbers, it is possible to determine an operating point of a specific fluidized bed condition (fluid dynamics) in a fluidization regime map. In 1986, Grace [30] presented a practical gas-solid fluidization map based on the work of Reh [31] in 1961. The map used an arrangement of dimensionless numbers, which were explicit and significant for the fluidization velocity on the vertical axis as an operational parameter (U*) and the particle diameters as a material property on the horizontal axis (d p *).…”

Section: Fluid Dynamics Of the Advanced Reactor Designmentioning

confidence: 99%

Syngas for biorefineries from thermochemical gasification of lignocellulosic fuels and residues—5 years’ experience with an advanced dual fluidized bed gasifier design

Schmid

Benedikt

Fuchs

et al. 2019

Biomass Conv. Bioref.

View full text Add to dashboard Cite

In many processes proposed for biorefineries, recycling procedures, and industrial or agricultural production processes, residue is generated which could be further transformed by thermochemical conversion via gasification. The technology of dual fluidized bed steam gasification is capable of producing a valuable product gas out of such residue. The generated nitrogen-free product gas can be used for heat and power production and is suitable for separating gases (e.g. hydrogen). However, if the product gas is cleaned, its use as syngas is more beneficial for manufacturing renewable chemical substances, like synthetic natural gas, methanol, Fischer-Tropsch liquids, or mixed alcohols. This paper presents the results of experimental research from gasification test runs of different biogenic fuels, carried out with an advanced 100 kW pilot plant over the last 5 years at TU Wien. The focus is to provide an overview of measured results validated by mass and energy balances and to present key calculated performance indicating key figures of the test runs. In this way, the influence of various operational parameters and the composition of the product gas are evaluated. The presented results form the basis for the proper design of suitable gas-cleaning equipment. Subsequently, the clean syngas is available for several synthesis applications in future biorefineries.

show abstract

Section: Fluid Dynamics Of the Advanced Reactor Designmentioning

confidence: 99%

Syngas for biorefineries from thermochemical gasification of lignocellulosic fuels and residues—5 years’ experience with an advanced dual fluidized bed gasifier design

Schmid

Benedikt

Fuchs

et al. 2019

Biomass Conv. Bioref.

View full text Add to dashboard Cite

show abstract

“…gas / liquid / solid and can be organized in so-called flow maps. This map indicates the most likely flow regime for the given regime of single phase streams and is provided in many research works [110,94,118]. The pattern of the flow depends on many factors like flow components, pipeline (its diameter, length, position, arrangement and shape etc.…”

Section: Flow Regime Identificationmentioning

confidence: 99%

Computer methods for non-invasive measurement and control of two-phase flows: a review study

Wajman

2019

ITC

View full text Add to dashboard Cite

Nowadays, the application of advanced technologies in modern production systems is the main trend of development and technological progress in many industrial sectors. It is due to the still growing trends of energy-saving and production quality enhancement. Wherever in the production process the phase mixture is transported and it is not optimal or not economic, there is a need to develop a system which would be able to prevent any construction disaster, unexpected production line stopping or situation where for reasons of bad flow parameters, the final product is defective. This paper studies various sensors, measurement techniques and computer methods for signal processing and analysis to diagnose and control two-phase flows. Due to the possibility that the invasive measurement disturbs the process and changes it parameters and behavior especially in the location just after the measurement point and simultaneously does not provide any information about these changes it is unreliable for the diagnosis or control. Therefore, the non-invasive techniques commonly used for measurement of flows parameters are described. Depending on the industrial demands many of applications examples for non-invasive two-phase flows measurement and monitoring are given. This description for identifying the flow parameters is divided into features categories of this phenomena as void fraction distribution, velocity profile and flow regime. However, from these methods the high accuracy and short processing time is expected. The continued observation and monitoring of the process abnormalities can provide valuable information about its dynamic state and allow for real-time and automatic monitoring and control. Therefore, the development of advanced process control is one of the most important challenges to keep the flow regime on the given level and for instant and long-term energy saving, quality improvement.

show abstract

“…Although Rabinovich and Kalman (2011) successfully characterized such a diagram for vertical pneumatic conveying systems, no suitable fl ow regime diagram for fl uid-solid horizontal conveying systems has been developed. This diagram enables the designer to predict appropriate fl ow regime for various particle and fl uid properties.…”

Section: The Generalized Fl Ow Regime Diagrammentioning

confidence: 99%

Threshold velocities of particle-fluid flows in horizontal pipes and ducts: literature review

Rabinovich

Kalman

2011

Reviews in Chemical Engineering

Self Cite

View full text Add to dashboard Cite

Numerous industrial processes such as conveying, fl uidizing and handling involve two-phase (fl uid-solids) fl ows. Investigation of the two-phase fl ow mechanisms have importance in both industrial manufacturing processes and natural phenomenon such as dust storms, erosion, air pollution and soil deposition in rivers and ocean fl ows. One of the most signifi cant parameters for designing two-phase (fl uid-solids) fl ow conveying systems is the fl uid velocity magnitude. Inaccurate determination of the fl uid velocity can lead to high energy consumption, particle attrition, pipe erosion and in some cases pipe blockage. This work reviews numerous studies presented in the literature concerning various threshold velocities in horizontal two-phase (fl uid-solids) fl ow systems. The threshold velocities include: incipient motion, pickup from a layer of particles, pickup from hill-shape particle deposits, boundary saltation and minimum pressure velocity. Most of the studies were conducted in pneumatic and hydraulic conveying systems and large-scale wind tunnels systems. As each threshold velocity characterizes a transition between two or more fl ow regimes and mode of particle movement, all possible fl ow regimes of the particle-fl uid horizontal conveying systems are present fi rst. Then the threshold velocity models and correlations are analyzed and compared. The theoretical models are compared for the forces and torque vectors taken into account for various threshold conditions and particle package geometry. In addition, the main parameters infl uencing the pickup and saltation mechanisms and the dimensionless numbers are reviewed. Finally, four threshold velocities are used to characterize a generalized fl ow regime diagram for horizontal conveying systems. This diagram makes a signifi cant contribution to researching and designing twophase fl ow systems. For example, the diagram may assist in the transition conditions between dilute and stratifi ed fl ow regimes. However, more theoretical and empirical research is required to discover all the possible states of horizontal systems.

show abstract

Flow regime diagram for vertical pneumatic conveying and fluidized bed systems

Cited by 76 publications

References 48 publications

Syngas for biorefineries from thermochemical gasification of lignocellulosic fuels and residues—5 years’ experience with an advanced dual fluidized bed gasifier design

Syngas for biorefineries from thermochemical gasification of lignocellulosic fuels and residues—5 years’ experience with an advanced dual fluidized bed gasifier design

Computer methods for non-invasive measurement and control of two-phase flows: a review study

Threshold velocities of particle-fluid flows in horizontal pipes and ducts: literature review

Contact Info

Product

Resources

About