Heat Transfer Requirement for

Consider the reaction system and production requirements discussed in Illustration 10.1. Consider the possibility of using one or more continuous stirred tank reactors operating in series. If each CSTR is to operate at 163 °C and if the feed stream is to consist of pure A entering at 20 °C, determine the reactor volumes and heat transfer requirements for... 

The heat transfer requirements for each reactor may be determined from equations of the form of equation B. 

In Illustration 10.7 we will consider how to meet the vast majority of the heat transfer requirements for operation of a semibatch reactor by a semiautothermal mode of processing. By... 

Interstage heat transfer requirements for different reactor network configurations. 

Solve reactive-system energy balance problems for (a) the heat transfer required for specified inlet and outlet conditions, (b) the outlet temperature corresponding to a specified heat input (e.g., for an adiabatic reactor), and (c) the product composition corresponding to a specified heat input and a specified outlet temperature. 

Determine the flow rates and the rate of heat transfer required for given conditions. 

At the time Kladko s article (5) was prepared, market conditions dictated that it would not be financially remunerative to develop a continuous process for producing B by the reaction discussed in Illustration 10.1 and other illustrations in this chapter. Consequently, they considered the possibility of using a semibatch reactor with continuous addition of cold feed to maintain the temperature of the reactor contents within prescribed limits. The basic problem was considered in Illustration 8.11. However, in addition to the material balance aspects of the design, we now wish to consider the heat transfer requirements for operation in accordance with the filling schedule outlined earlier. For the conditions indicated in Illustration 8.11 (isothermal, 163°C) determine the direction and magnitude of the heat transfer requirements. 

The economics of processing depend on the thermal characteristics of the material. The thermal properties of PP are compared with some other plastics in Table 23. The heat transfer requirement for cooling from the melt temperature to mould temperature in the case of PP is much higher than those in the case of amorphous polymers such as ABS and PS. Hence, the processing of PP is costly. In addition, thermal conductivity determines the cooling time of the material in the mould. It can be seen that the thermal conductivity of PP is less than HOPE. It would require more cooling time, and hence, a slower production rate. 

Polymer Heat transfer requirement for cooling from the melt temperature (kJ/kg) Thermal conductivity at 20 °C (W/m K)... 

Some Beyond Design Basis fault sequences could result in a core melt in such circumstances reactor vessel integrity and therefore prevention of a large release of radioactivity is maintained by flooding the reactor cavity with water, thereby cooling the vessel by evaporation within its insulation. Changes have been made to the flow path between the outside of the reactor vessel and the reactor vessel insulation, and testing has confirmed the robustness of the heat transfer required for in-vessel retention (Section IB. 1.5 ofReference 6.1). 

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