Jacketed vessels types

Equipment, The reactor was 1.523 liter, 316 stainless steel cylindrical, jacketed vessel equipped with two multiblade, paddle-type agitators. Tracer studies showed the reactor was well-mixed. A thermocouple measured temperature and was recorded continuously. Feed tanks, tubing, pumps and valves were made of stainless steel and had teflon seals. 

Two types of process vessel are likely to be subjected to external pressure those operated under vacuum, where the maximum pressure will be 1 bar (atm) and jacketed vessels, where the inner vessel will be under the jacket pressure. For jacketed vessels, the maximum pressure difference should be taken as the full jacket pressure, as a situation may arise in which the pressure in the inner vessel is lost. Thin-walled vessels subject to external pressure are liable to failure through elastic instability (buckling) and it is this mode of failure that determines the wall thickness required. 

There are a number of different types of adiabatic calorimeters. Dewar calorimetry is one of the simplest calorimetric techniques. Although simple, it produces accurate data on the rate and quantity of heat evolved in an essentially adiabatic process. Dewar calorimeters use a vacuum-jacketed vessel. The apparatus is readily adaptable to simulate plant configurations. They are useful for investigating isothermal semi-batch and batch reactions, and they can be used to study ... 

Mixer and mixing vessel subclasses primarily are distinguished by the mixing energy, mixer type, and whether a jacketed vessel with vacuum capabilities is used in conjunction with a specific mixer. 

The most common types of SCWO reactors are cylindrical vessels or pipes. The vessel-type reactors (i.e., length/diameter ratio <20) typically have a vertical orientation with process flow directed downward. Pipe reactors (i.e., length/ diameter ratio >100) typically are mounted horizontally and are often coiled, since they need to be longer than vessel reactors to achieve the same residence time. SCWO reactors may have external heating (e.g., heating coils, steam jacket) or may rely solely on heated process fluid and the heat of reaction to reach and maintain the desired internal temperature under steady-state conditions. 

Heat transfer can occur in either batch or continuous configurations. Both types of processes require fluid motion to obtain an effective heat transfer to the bulk of the fluid. In batch processing using jacketed vessels, helical coils, or coils in a baffle configuration, for example, sufficient agitation is required for heat transfer through the medium while continuous systems rely on flow rate to achieve effective heat transfer to satisfy process requirements. Effective heat transfer in batch operations for structured liquid detergents may require scrapers or anchor-type impellers to increase heat transfer coefficients in jacketed vessels. 

Drier, steel, jacketed vessel with connections to condenser coil and receiver. Charge from still can be dischar d by air pressure through standpipe to reduction plant. Condensate receiver has dip-pipe connection to permit condensate to be blown to second washer. Gate-type stirrer rotates at 28 rpm... 

Figure 2-49. Some acceptable types of jacketed vessels.

Dewars are generally the open type, non-pressurized vacuum-jacketed vessels used to contain cryogenic liquids. Cryogenic liquid cylinders are closed, pressurized vessels. 

High-speed chums are designed to speed up the preparation of smooth cements. Because of their shearing action, they provide some polymer breakdown and resultant viscosity reduction. They generate considerable heat, so a jacketed vessel is preferred to control heat history. The heat build-up increases the rate of solution, particularly with the crystalline types because in addition to the simple temperature effect on solubility, heating deciystallizes the polymer. 

This type of calorimeter is nomrally enclosed in a themiostatted-jacket having a constant temperature T(s). and the calorimeter (vessel) temperature T(c) changes tln-ough the energy released as the process under study proceeds. The themial conductivity of the intemiediate space must be as small as possible. Most combustion calorimeters fall into this group. 

A liquid serves as the calorimetric medium in which the reaction vessel is placed and facilitates the transfer of energy from the reaction. The liquid is part of the calorimeter (vessel) proper. The vessel may be isolated from the jacket (isoperibole or adiabatic), or may be in good themial contact (lieat-flow type) depending upon the principle of operation used in the calorimeter design. 

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. 

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