Liquid fluidized bed reactor

Trinet, F., Fleim, R., Amar, D., Chang, H. T., and Rittmann, B. E., Study of Biofilm and Fluidization of Bioparticles in a Three-Phase Liquid-Fluidized-Bed Reactor, Wat. Set. Tech., 23 1347 (1991)... 

Chem Systems Inc. has been developing a three phase reaction system for methanol synthesis since the mid 1970 s (ref. 28). The original concept incorporated a liquid-fluidized-bed reactor. This research, which was funded by the Electric Power Research Institute, used particles of a heterogeneous catalyst, obtained by crushing pellets of a commercial Cu-ZnO-AljO type catalyst, which was fluidized by a circulating inert hydrocarbon liquid such as a mineral oil. One of the major benefits of the process over conventional synthesis is claimed (ref. 28) to be excellent temperature control of the reactions so that higher per pass conversions can be achieved, thereby reducing... 

Stirred tank crystallizers, see Section 16.11.4.6 and reactors. Sections 16.11.6.23 through 16.11.6.25. Liquid fluidized bed reactors. Section 16.11.6.26 hquid adsorption, Section 16.11.4.12 ion exchange, Section 16.11.4.13 backwash fixed-bed operations such as deep-bed filters. Section 16.11.5.13 liquid adsorbers. Section 16.11.4.12 and ion exchangers. Section 16.11.4.13. 

A final early concept for a PWR was a pebble-bed system. This concept, developed by the Martin Company, was known as the liquid fluidized bed reactor (LFBR). The concept... 

Ruidized beds find wide application as chemical reactors. The most common ones are catalytic gas phase reactors. The catalyst is then usually a fine powder, with a particle size of about 0.1 mm. Occasionally liquid-fluidized beds reactors are used, e.g., for processes using ion exchange resins or inunobilized enzymes. Then the particles are usually around 1 nun. 

By contrast, if the reactor is continuous well-mixed, then the reactor is isothermal. This behavior is typical of stirred tanks used for liquid-phase reactions or fluidized-bed reactors used for gas-phase reactions. The mixing causes the temperature in the reactor to be effectively uniform. 

Three-phase fluidized bed reactors are used for the treatment of heavy petroleum fractions at 350 to 600°C (662 to 1,112°F) and 200 atm (2,940 psi). A biological treatment process (Dorr-Oliver Hy-Flo) employs a vertical column filled with sand on which bacderial growth takes place while waste liquid and air are charged. A large interfacial area for reaction is provided, about 33 cmVcm (84 inVirr), so that an 85 to 90 percent BOD removal in 15 min is claimed compared with 6 to 8 h in conventional units. 

The calcium bisulfite acid used in the manufacture of sulfite cellulose is the product of reaction between gaseous sulfur dioxide, liquid water, and limestone. The reaction is normally carried out in trickle-bed reactors by the so-called Jenssen tower operation (E3). The use of gas-liquid fluidized beds has been suggested for this purpose (V7). The process is an example of a noncatalytic process involving three phases. 

Recent research development of hydrodynamics and heat and mass transfer in inverse and circulating three-phase fluidized beds for waste water treatment is summarized. The three-phase (gas-liquid-solid) fluidized bed can be utilized for catalytic and photo-catalytic gas-liquid reactions such as chemical, biochemical, biofilm and electrode reactions. For the more effective treatment of wastewater, recently, new processing modes such as the inverse and circulation fluidization have been developed and adopted to circumvent the conventional three-phase fluidized bed reactors [1-6]. 

The copper was efficiently recovered more than 95-98% from the wastewater of electronic industries within 2-3 hrs as a powder by employing the three-phase inverse fluidized-bed reactors. The addition of a small amount of gas(Uc= 0.001) or fluidized particles(W=1.0wt.%) into the inverse fluidized bed reactors resulted in the increase of the copper recovery and decrease in the size of copper powda-recovered. The value of copper recovery exhibited a maximum value with increasing gas or liquid velocity, amount of fluidized particles or distance between the two electrodes, but it increased gradually with increasing current density up to 3.5A/dm between the two electrodes. The optimum conditions for the maximum recovery of copper powder were UG=0.001m/s, Ul= O.OOlm/s, W=1.0wt.%, I=3.5A/dm and LAc=0.015m within this experimental conditions. 

Half maximal effective concentration 17a-Ethinyl estradiol Fluidized bed reactor 1 -Hydroxybenzotriazole High performance liquid chromatography Hydraulic retention time... 

There are a wide variety of three-phase fluidized bioreactor designs possible. The conventional reactor, shown in Fig. 9, is fluidized by both gas and liquid entering at the bottom of the reactor and leaving at the top and is the most common type of three-phase fluidized bed bioreactor. This reactor may be configured to operate with little axial liquid mixing or in a well-mixed mode by adding a recycle stream. The airlift reactor or draft tube fluidized bed reactor, Fig. 10, is also frequently used. In this reactor, gas is injected at the bottom of a draft tube placed in the center of the... 

Wisecarver, K. D., and Fan, L. S., Biological Phenol Degradation in a Gas-Liquid-Solid Fluidized Bed Reactor, Biotechnol. Bioeng., 33 1029 (1989)... 

Water pump fails Liquid HF not vaporized, passed to fluidized bed reactor, off-spec or no product. None. 6 Consider adding a low temperature interlock on HF (N2) flow. 

Spheripol A process for making polypropylene and propylene co-polymers. Homopolymerization is conducted in the liquid phase in a loop tubular reactor co-polymerization is conducted in the gas phase in a fluidized-bed reactor. The catalyst is treated with a special silane. The product is in the form of beads of up to 5 mm in diameter. Developed by Montecatini, Italy, and first licensed by Himont, United States, and Mitsui Petrochemical Industries, Japan. In 1989, 29 licenses had been granted worldwide. Now offered for license by Montell, a joint venture between Montedison and Shell. See also Addipol. 

Our treatment of Chemical Reaction Engineering begins in Chapters 1 and 2 and continues in Chapters 11-24. After an introduction (Chapter 11) surveying the field, the next five Chapters (12-16) are devoted to performance and design characteristics of four ideal reactor models (batch, CSTR, plug-flow, and laminar-flow), and to the characteristics of various types of ideal flow involved in continuous-flow reactors. Chapter 17 deals with comparisons and combinations of ideal reactors. Chapter 18 deals with ideal reactors for complex (multireaction) systems. Chapters 19 and 20 treat nonideal flow and reactor considerations taking this into account. Chapters 21-24 provide an introduction to reactors for multiphase systems, including fixed-bed catalytic reactors, fluidized-bed reactors, and reactors for gas-solid and gas-liquid reactions. 

Figure 8.3. Gas-Liquid Fluidized Bed C"Ebullating" Reactor for Hydroliquefaction of Coal CKampiner, in Winnacker-Kuehler, Chemische Technolagie 52, 19723. ...

Catalytic coal liquefaction processes do not specifically use hydrogen donor solvents although coal is introduced into the liquefaction reactor as a slurry in a recycle liquid stream. Catalyst is used as a powder or as granules such as pellets or extrudates. If powdered catalyst is used, it is mixed with the coal/liquid stream entering the reactor. Pelleted catalyst can be used in fixed bed reactors if precautions are taken to avoid plugging with solids or in fluidized bed reactors. In the latter case, the reacting system is actually a three phase fluidized bed, that is, catalyst particles and coal solids, as well as liquid, are fluidized by gas. 

The experiments were carried out on a semi-industrial fluidized bed reactor, illustrated in Figure 9.6, which shows four different sensor positions (A, B, C and D). Screw fittings were used to mount the sensors in order to secure optimal sensor pickup efficiency. Sensor location A is mounted onto an orifice plate on the main supply line of liquid urea to the reactor nozzles, following Esbensen et al. [5]. The sensors B, C and D are located on the wall of reactor chambers 1, 2 and 4, respectively. 

Heterogeneous reactions are typically performed in solid and liquid phase reaetors typically fixed bed and fluidized bed reactors (Figure 1) and wall reaetors (Figure 2) wherein the contact time and the ratio of solid/liquid phase are different and ean be moderated. 

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