Baffles glass-lined

Burner nozzles, stack damp eis, boiler baffles, furnace linings, glaSS molds... 

For glass-lined vessels with finger-type baffle... 

In steel or alloy vessels, the recommended baffle design for suspension of settling solids is four, flat-blade baffles, each baffle with a width, B, equal to r/12, and a wall clearance of at least 7/72. The baffles should extend to the lower end of the straight section of the cylindrical vessel, at the intersection of the cylindrical section with the bottom dish head. In glass-lined equipment, the recommended baffles are either fln or beaver tail types.A minimum of two baffles is recommended. These baffles are generally less effective than the standard four flat-blade baffle design. 

CSTR is used when intense agitation is required. Figure l-7(a) showed a cutaway view of a Pfaudler CSTR atch reactor. Table 1-1 gives the typical sizes (along with that of the comparable size of a familiar object) and costs for batch and CSTR reactors. All reactors are glass lined and the prices include heating/cooling jacket, motor, mixer, and baffles. The reactors can be operated at temperatures between 20 and 4. )0 F and at pressures up to 100 psi. 

Some early batch polymerization reactors were built on rotating shafts to copy the action of bottle polymerizers. These reactors were expensive and difficult to maintain. They were replaced by standard stirred vessels which are commonly used today. Typical batch reactors contain an agitator that is mounted in the center of the reactor top. The reactors are often glass lined and contain one or more baffles to enhance mixing. Heat removal is accomplished by circulating a coolant through the reactor jacket. 

A common vessel used in the batch production of fine chemicals and pharmaceutical is the jacketed glass-lined reactor-still as shown in Figure 9.18. It is available in 5 to 4,000 gallon capacities and is usually fitted with a retreat curve agitator and single baffle or thermowell/baffle assembly cantilevered from the vessel lid, a distillation column, and a condenser. The same temperature sensor... 

The outside coefficient, ho, is quite low for water in a simple open jacket. It can be increased by using agitation nozzles, a spiral baffle in the jacket, or a half-pipe coil welded to the tank [1,2]. The wall resistance is usually negligible for a steel tank, but it may be significant for a thick stainless steel wall or for a glass-lined reactor. 

Into a 1,000 gallon, jacketed, glass lined reactor equipped with baffles and a two speed (67 and 135 rpm) reversed impeller is introduced 200 g of Richonate 60S (a 60% aqueous slurry of sodium salts of alkylbenzenesulfonic acids) and 364 liters of deionized water, followed by... 

Standard baffles fitted to glass-lined vessels are the finger type (shaped like an inverted F), the d-shaped type, and, more recently, the h-shaped type. 

For glass-lined vessels and retreat curve blade impellers and glass-lined turbines, five different types of baffles (shown in Figure 6-7) are commonly used Anger, flattened pipe, h style, concave baffle, and fin. These baffles can be conveniently supported in the vessel heads of glass-lined reactors. Of these, the fin baffle has become a more standard choice. 

Figure 6-7 Common glass-lined baffle types.

What is the appropriate material of construction for the process vessel The main issue here is that, for steel or alloy vessels, the standard four wall-mounted baffles provide a better environment for solid-liquid mixing. The standard glass-lined vessels are usually underbaffled because of a deficiency of nozzles from which to mount baffles. 

In glass-lined equipment, the recommended baffles are either fin or beaver-tail type (see Chapter 17). A minimum of two baffles is recommended. These baffles are generally less effective than the standard four flat blade baffles. 

The pH of the latter nutrient medium is adjusted to 7.5 with ION sodium hydroxide solution and is placed in a 30 liter glass fermentor equipped with sparger, impeller, baffles and sampling line. The medium is sterilized by heating at 121°C for two hours, is allowed to cool and is then inoculated with 800 ml of the culture mixture obtained as described above. 

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