Hybrid reactor

Technology Description Hybrid reactors, as the name implies, are a combination of suspended growth and fixed-film reactor principles. In these systems, the fixed film is submerged and the reactor contents are continuously stirred. A large amount of biomass is maintained in the system. 

Kalyuzhnyi, S.V., Saucedo, J.V., and Martinez, J.R., The anaerobic treatment of soft drink wastewater in UASB and hybrid reactors, Applied Biochemistry and Biotechnology, 66, 291-301, 1997. 

The anaerobic hybrid reactor is generally a combination of suspended growth and attached growth systems. Recently, this technology has become popular in the treatment of industrial wastewater, in particular in cases of high-strength wastewater. It has been reported that this... 

Henary, M.P. Donlon, B.P. Lens, P.N. Colleran, E.M. Use of anaerobic hybrid reactor for treatment of synthetic pharmaceutical wastewaters containing organic solvents. J. Chem. Technol. Biot. 1996, 66, 251-264. 

An interesting contribution to the field of single-mode equipment has been recently presented by Milestone. The MultiSYNTH instrument (Fig. 3) is a kind of hybrid reactor as it combines the inherent advantages of single-... 

Until now, bioreactors of various types have been developed. These include loop-fluidized bed [14], spin filter, continuously stirred turbine, hollow fiber, stirred tank, airlift, rotating drum, and photo bioreactors [1]. Bioreactor modifications include the substitution of a marine impeller in place of a flat-bladed turbine, and the use of a single, large, flat paddle or blade, and a newly designed membrane stirrer for bubble-free aeration [13, 15-18]. Kim et al. [19] developed a hybrid reactor with a cell-lift impeller and a sintered stainless steel sparger for Thalictrum rugosum cell cultures, and cell densities of up to 31 g L1 were obtained by perfusion without any problems with mixing or loss of cell viability the specific berberine productivity was comparable to that in shake flasks. Su and Humphrey [20] conducted a perfusion cultivation in a stirred tank bio-... 

The approach being used to achieve this result was described recently by KTI reporting on work carried out for the Electric Power Research Institute (13). The basic scheme, in block diagram form, is shown in Figure 12. It consists of a hybrid reactor combining an advanced tubular steam reformer with an autothermal catalytic reformer. This combination overcomes the limitations of lower catalytic activity in HTSR systems toward the heavier hydrocarbons while retaining a significant part of the desired process characteristics. 

Development of the hybrid reactor technique is entering a bench scale experimental program, to be followed with a small scale prototype unit scheduled for operation late in 1979. 

L4.7 Hybrid Reactors Combining Membrane and Conventional Reactors... 

These equations can be easily adjusted to reaction conditions, for example, replacing S with light intensity for photosynthetic reactions. A hybrid reactor, consisting of suspended biomass, as above, plus particles coated with biofilm, can be evaluated by segregating the two systems for separate analysis and then adding the two contributions. 

The introduction of solid catalysts into a traditionally non-catalytic free-radical process like combustion occurred in recent years under the influence of two pressures, the energy crisis and the increased awareness of atmospheric emissions. The major applications of catalytic combustion are twofold at low temperatures to eliminate VOC s and at high temperatures (>1000 C) to reduce NOx emission from gas turbines, jet motors, etc. Both these applications are briefly reviewed here. Some recent developments in high-temperature catalytic combustion are trend-setters in catalysis and hence of particular interest. For instance, novel materials are being developed for catalytic applications above 1000 C for sustained operation for over one year. Where material/catalyst developments are still inadequate, systems engineering is coming to the rescue by developing multiple-monolith catalyst systems and the so-called hybrid reactors. 

Two broad classes of reactors can be identified batch reactors and flow reactors. The two types also involve two types of operation transient and steady state. In some reactor configurations, aspects of more than one type of reactor are incorporated into one unit, a practice that should be carefully examined case by case for its applicability to the work to be done and its ability to deliver reliable and valid data. Such hybrid reactors are in general tricky to operate and have a limited range of accessible operating conditions. Although they can be built to simulate plant operating conditions, they are usually a poor source of kinetic data, particularly if it is to be used to understand the dependence of the reaction rate over a broad range of reaction conditions or to quantify the reaction mechanism. 

Groppieta/. (L),(S) Parametric study of the influence of design variables in particular hybrid reactors... 

Groppi et al. (D), (S) Different levels of model complexity to address simplified treatments in hybrid reactors... 

A comparison between lumped and distributed models for hybrid reactors for catalytic combustion of methane was more recently investigated by Groppi et a/. The validation of one-dimensional models was made on the basis for different Nusselt correlations and geometrical properties of the monolith channel. In general, the simulations showed a mismatch of the wall temperature profiles predicted with the one-dimensional model. One-dimensional models could show good agreement of the gas exit temperature, which is an important parameter for hybrid reactors as described in the previous section. The catalyst has to ignite in... 

Hybrid reactors reverse flow, reactive distillation, reactive extraction, reactive crystallization, chromatographic reactions, membrane reactions, fuel cells... 

Ryu J,ChoiW and Choo K-H (2005), A pilot-scale photocatalyst-membrane hybrid reactor performance and characterization . Water Sci Technol, 51,491-497. 

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