Mixer jacket

Oil or electric heated 650 ml sigma mixer is used in this method. Temperature of mixer jacket is adjusted to 88°C. Standard formulation is used for this test, containing PVC - 225 g, Burgess No. 30 clay - 40 g, and diisodecyl phthalate - 124 g. Time is measured from the moment of plasticizer addition to the diy point which is easy to determine from a sudden drop of torque. 

In a typical commercial dry jet-wet spinning process, PPT polymer of inherent viscosity 6.0 dL/g is added to 99.7% sulfuric acid in a water-jacketed commercial mixer in a ratio of 46 g of polymer to 100 mL of acid. The mixture is sealed in a vacuum of 68.5—76 mL of mercury. Mixing takes place for 2 h... 

Convection. In these mixers an impeller operates within a static shell and particles are moved from one location to another within the bulk. bbon Tjpe. Spiral or other blade styles transfer materials from one end to the other or from both ends to the center for discharge (Fig. 37b). This mixer can be used for dry materials or pastes of heavy consistency. It can be jacketed for heating or cooling. Blades can be smoothly contoured and highly pohshed when cleanliness is an important process requirement. 

A stable crystalline form for chocolate depends primarily on the method used to cool the fat present in the Hquid chocolate. To avoid the grainy texture and poor color and appearance of improperly cooled chocolate, the chocolate must be tempered or cooled down so as to form cocoa butter seed crystals (31). This is usually accompHshed by cooling the warm (44—50°C) Hquid chocolate in a water jacketed tank, which has a slowly rotating scraper or mixer. As the chocolate cools, the fat begins to soHdify and form seed crystals. Cooling is continued to around 26—29°C, during which time the chocolate becomes more viscous. If not further processed quickly, the chocolate will become too thick to process. 

This chapter reviews the various types of impellers, die flow patterns generated by diese agitators, correlation of die dimensionless parameters (i.e., Reynolds number, Froude number, and Power number), scale-up of mixers, heat transfer coefficients of jacketed agitated vessels, and die time required for heating or cooling diese vessels. 

In batch processing, the various additives are mixed with the prepolymer component in a jacketed horizontal (Z-blade) or vertical (helicone or spiral) mixer. Prior to this, however, a high-speed liquid mixer is used to dis-... 

The correlations of Cummings and West [5, 29] for turbine mixers in vessels with Jackets and coils are ... 

Tank diameter, ft, or L (consistent units). Figure 5-34 = Residence or holding time, sec, or time of mixing = Overall heat transfer coefficient, bulk mixing liquid to transfer fluid on opposite side of heat transfer wall (coil, plate, jacket), Btti/hr/sq ft/°F = Velocity of mixed fluids through mixer, ft/sec = Volume, consistent units... 

Figure 5.28 Schematic of the experimental set-up. Water/ethylene glycol/SDS reservoir (a) high-pressure liquid pumps (b) catalyst/ substrate HPLC injection valve with 200 pi sample loop (c) hydrogen supply, equipped with mass flow controller (d) micro mixer (e) heating jacket (f) tubular glass or quartz reactor (g) back-pressure regulator (h) [64],...

The tank will be jacketed with steam to heat the solution to 120°F before it is discharged. A small agitator of less than 1 hp will be used as a mixer. 

While the Dove composition described in Table 9.4-2 was processable at reasonable line speeds on a conventional soap processing line (roll mills, extruders, stampers), some equipment modifications were necessary. For example, whereas soap is normally mixed in large agitated tanks, the Dove mixture had a much greater viscosity and therefore required use of a steam-jacketed kneader mixer such as those used to make bread dough, pastes or mastics. 

The process begins in a prepolymerizer, which is a water-jacketed reactor with a mixer in it. See Figure 23—12.) The styrene is partially polymerized by adding the peroxide initiator and heating to 240—250°F for about four hours. About 30% of the styrene polymerizes and the reactor contents become syrupy goo. Thats about as far as the prepolymer step can go—30% conversion— because the mixing and heat transfer gets very inefficient as the goo gets thicker, and the polymerization becomes hard to control. 

Mix Process. Usually all liquid components (except the diisocyanate), antioxidants, ballistic additives, bonding agents, and metallic fuel are blended together and transferred to the mixer, a jacketed stainless steel vessel with provisions for vacuum mixing. This mixer is not much different from those found in the bread-baking industry, from which, in fact, this one was derived. Depending on the type of propellant, the... 

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