Rotating disc contactor

K. Liquid-liquid extraction in Rotating-disc contactor (RDC)... 

Solvent Extraction - Solvent extraction uses solvents to dissolve and remove aromatics from lube oil feed stocks, improving viscosity, oxidation resistance, color, and gum formation. A number of different solvents are used, with the two most common being furfural and phenol. Typically, feed lube stocks are contacted with the solvent in a packed tower or rotating disc contactor. Each solvent has a different solvent-to-oil ratio and recycle ratio within the tower. 

LEDA [Low energy de-asphalting] A process for removing the asphalt fraction from petroleum residues by liquid-liquid extraction in a special rotating disc contactor. The extractant is a C3-C6 aliphatic hydrocarbon or a mixture of such hydrocarbons. Developed in 1955 by Foster Wheeler USA Corporation and still widely used 42 units were operating in 1996. 

Mechanical agitation Group E Rotating disc contactor Oldshue-Rushton column Zeihl column Graesser contractor Group F Scheibel column Mixer-settlers... 

Industrial hazardous wastewater can be treated aerobically in suspended biomass stirred-tank bioreactors, plug-flow bioreactors, rotating-disc contactors, packed-bed fixed-biofilm reactors (or biofilters), fluidized bed reactors, diffused aeration tanks, airlift bioreactors, jet bioreactors, membrane bioreactors, and upflow bed reactors [28,30]. 

Steam coils at the top of the tower maintain the specified temperature gradient across the rotating disc contactor. The higher temperature in the top section of the rotating disc contactor results in separation of the less soluble heavier material from the deasphalted oil mix and provides internal reflux, which improves the separation. The deasphalted oil mix leaves the top of the rotating disc contactor tower. It flows to an evaporator where it is heated to vaporize a portion of the solvent. It then flows into the high pressure flash tower where high pressure solvent vapors are taken overhead. 

The raffinate phase containing asphalt and a small amount of solvent flows from the bottom of the rotating disc contactor to the asphalt mix heater. The hot, two phase asphalt mix from the heater is flashed in the asphalt mix flash tower where solvent vapor is taken overhead, condensed, and collected in the low pressure solvent receiver. The remaining asphalt mix flows to the asphalt stripper where the remaining solvent is stripped overhead with superheated steam. The asphalt stripper overhead vapors are combined with the overhead from the deasphalted oil stripper, condensed, and collected in the stripper drum. The asphalt product is pumped from the stripper and is cooled by generating low pressure steam. 

Fei WY, Wang YD, Wan YK. Physical modelhng and numerical simulation of velocity fields in rotating-disc contactor via CFD simulation and LDV measurement. Chem Eng J 2000 78 131-139. 

The extractors are York rotating disc contactors, 3-inch ID by 48-inch long. Three contactors are to be used, one each for extraction, scrubbing, and stripping. The system will be used to investigate the recovery of plutonium and americium from MSE waste salt solutions using 30% DHDECMP in diisopropylbenzene. 

Code AC (Agitated CeU) - PTC (Pulsed Packed Cdumn) - PST (Pulsed Sieve Tray) - RDC (Rotating-Disc Contactor - PC (Pecked Column) - MS (Mixer Settler) - ST (Sieve Tray)... 

Ghalehchian, j. S. 2002 Prediction of the hydrodynamics of rotating disc contactors based on a new Monte-Carlo simulation method for drop breakage. Journal of Chemical... 

RDC Column. The rotating disc contactor (Fig. 19) provides for redispersion by a series of discs along the shaft, combined with a series of fixed stators. Vortices are formed in each compartment, and the shear of the fluid against the rotor or stator causes the drop breakup. In many instances. 

The rotating disc contactor (B), developed in the Netherlands in 1951, uses the shearing action of a rapidly rotating disc to interdisperse the phases. These have been used in the petrochemical industry for furfural and SOj extraction, propane deasphalting, sulfolane extraction for the separation of aromatics from aliphatics, and caprolactam purification. Columns up to 4.3 m in diameter are in service. 

Figure 11.5 Rotating disc contactor with countercurrent downward flow of liquid and upward flow of gas or lower density liquid.

Fig. 6.3-4 Typical performance data of ten different extractor designs for the system tolulene/acetone/water. MS mixer-settler, SE static sieve tray column, PC static packed packed column, RDC rotating disc contactor, PSE pulsed sieve tray column, PPC pulsed packed column, RZE agitated cell extractors...

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