Heat balance during growth

Figure 3. Changes in size distribution with time during growth of ice crystal seeds in 6% lactose under batch or semi-batch growth conditions, concentration processes based on suspension growth. In addition, the relation of this observed widening to the heat balance conditions needs to be further explored.

The Au films were evaporated from different resistively heated sources as well as from an electron beam evaporator. The Au frlm thicknesses and the growth rates were determined during growth by a quartz micro balance. 

Agglomeration in low density fluidized beds is different in that at least part of the drying takes already place during growth and in the equipment itself The stochastic movements of gases, droplets, and particles, the occurrence of coalescence and bonding and the mechanisms of drying can be modeled and mass, particle size, heat and moisture balances can be established [B.49, B.72, B.93]. Nevertheless, it is an art, performed by experienced personnel of specialized vendors, to successfully scale-up from the performance of test units to commercial equipment and systems. Capacity increases are often obtained by installation of multiple feed points (gas and powder inlets, liquid spray nozzles), which are housed in suitably sized and shaped containments (e.g., towers). 

Figure 4.2 shows that thermal conductivity, specific heat capacity and surface tension are urgently required. Although thermal conductivity is required to calculate heat balance at the soHd/Hquid interface during crystal growth and is important to... 

Temperature Effects During the condensation/evaporation of a particle latent heat is released/absorbed at the particle surface. This heat can be released either toward the particle or toward the exterior gas phase. As mass transfer continues, the particle surface temperature changes until the rate of heat transfer balances the rate of heat generation/ consumption. The formation of the external temperature and vapor concentration profiles must be related by a steady-state energy balance to determine the steady-state surface temperature at all times during the particle growth. 

A new insight in the population balance of zeolite crystallization is given, by introduction of new functions of nucleation and crystal growth as well as the correction of the crystal growth curves by introduction of the heating function of the reaction mixture. The modified population balance is used for the analysis of the critical processes (nucleation and crystal growth of zeolite) during crystallization of zeolites A, X and ZSM-5. 

Upon formation of the liquid phase during homogeneous condensation there is heat evolution Qin characterized by a heat of condensation I (kj kg ). Therefore, the temperature in the throttle does not decrease as sharply as in the absence of condensation. To correct for calorification, it is necessary to take into account Qin in the energy balance equation. If it is accepted that germs are formed practically instantly, then Qin will consist of two additive terms. The first characterizes the heat evolution upon the formation of germs, and the second the heat evolution upon further condensation growth of drops ... 

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