Agitation reactors

This reaction can also be mn in a continuous fashion. In the initial reactor, agitation is needed until the carbon disulfide Hquid phase reacts fully. The solution can then be vented to a tower where ammonia and hydrogen sulfide are stripped countercurrendy by a flow of steam from boiling ammonium thiocyanate solution. Ammonium sulfide solution is made as a by-product. The stripped ammonium thiocyanate solution is normally boiled to a strength of 55—60 wt %, and much of it is sold at this concentration. The balance is concentrated and cooled to produce crystals, which are removed by centrifiigation. 

Extent of emergency power supplies for lighting, communication systems, and key items of equipment (e.g. cooling facilities, reactor agitators, exhaust ventilation) and instruments/alarms. 

Figure 4. Monomer conversion vs. time of polymerization of styrene in a hatch reactor agitation speed as parameter...

Determine the heat addition and heat removal capabilities of the reactor. Don t forget to consider the reactor agitator as a source of energy—about 2550 Btu/(h hp). 

The rate experiments were carried out in 3.5 liter glass jars covered with a plexiglass lid. Two baffles of 2 cm width extended from the lid to 1 cm from the bottom of the reactor. Agitation was provided by a stirring motor with polyethylene stirrers, and the speed of the motor was controlled with a variac. Three liters of solution without the adsorbent particles was agitated, and allowed to reach equilibrium with the vessel before withdrawing the initial sample for analysis. At time t - 0, a measured quantity of activated carbon was introduced into the reactor and agitated. Samples, 10 ml each were withdrawn periodically, until equilibrium was reached, and analyzed for the solute concentration in the liquid phase. The numerical procedure developed earlier was adjusted to allow for the volume reduction due to the withdrawal of samples at discrete time Intervals. 

Fig. 37. Production diagram of antifoaming silicone emulsion 1 - reactor agitator 2, 3 - batch boxes 4 - reactor emulsifier 5 - hydrodynamic changer 6 -pump 7- collector...

It would be useful to have liquid present in the polymerization reactor that provided the advantages of a solvent but without any of the disadvantages. Sound unlikely How about water One technique, called suspension polymerization, involves adding monomer to water in a reactor, agitating the mixture rapidly so that the monomer breaks apart into very small droplets, adding an initiator that is soluble in the monomer, and heating. Each droplet acts as a microbulk polymerization, the water very effectively removes the heat of polymerization, and the resulting polymer spheres are easily separated and filtered. This process, also known as bead polymeriza-... 

Selection of a polymerization reactor depends on production costs, simplicity, and energy efficiency, all of which depend on the viscosity and the non-Newtonian rheological properties of the reaction mixture (Oldshue et al, 1982 Middleman, 1977). Flow properties significantly influence the nature of the reactor, agitator size, power, and design (Gerrens, 1982). 

The mixing curve can be obtained for any reactor/agitator system. Equipment vendors usually have a curv e for a particular system, provided the agitator blades, baffling and other internals have not been altered. An alternative is to build a geometrically similar model in the laboratory and determine the mixing curve with a mixing kit [2,3 ... 

The system depicts improved reactor agitator design and improved automation. The complete process is controlled by programmable logic controllers (PLCs), giving precise in-point control that leads to extreme consistency from batch to batch. 

Scale- Up Agitated Vessels with Recycle Loops with Semi-Batch Feed to an In-Line Mixer in the Recycle Loop. Knight (1995) and Colleagues (1995) conducted a rather definitive study that determined the pertinent scale-up parameters for a static mixer in a recycle loop. They used a 20 liter semi-batch reactor agitated with... 

Figure 10.47. Yield data vs initial molar feed ratio for 3 Bourne Reaction occurring in a 1/4 inch (0.64 cm) Kenics Helical Element Mixer used on a recycle loop on 20 liter semi-batch reactor agitated with a 6BD impeller.

Fig 6.3. Reactor agitation as provided by a six blade Rushton turbine. Gas dispersion is enhanced by holes in the hollow shaft. (Courtesy Autoclave Engineers.)... 

Some systems which have mechanical parts that perform work are turbines, mixers, engines, stirred tank reactors, agitators, and many others. The type of work performed by these parts is called shaft work to distinguish it from work due to expansion of the system itself (which is called expansion work). 

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