Drying continuous process validation

Due to this principle, a batch B defined for quality control purposes consists of a fixed number of n mini batches (subunits), i.e., B=nb.Thus, a tight in-process control of the mixing/granulation (6-9) and drying step (14) provides an excellent batch record of the quasi-continuous production of granules and an excellent opportunity for a continuous validation of the process and the equipment (14-18,32-34). 

In conclusion, drug A production was shown to be within established specifications, and there is no reason to believe this will not be the case for future production as long as all practices are continued in their present form. Furthermore, there is no significant difference between batches produced by the tray dryer process and the fluid bed process. A validation report should memorialize these findings. The report should also recommend eliminating the option to use a no. 5 screen for the wet milling step and a no. 12 screen to pulverize the dried granulation. There is no experience or only limited experience with this equipment that supports its continued availability. In the same vein, the final blend time should be standardized at 10 min and automatically controlled by means of a timer. 

The only validated CFD model of a pulse combustion spray-drying process has been presented by Zbicinski et al (1999) and Smucerowicz (2000). The two-dimensional axi-symmetric CFD calculations of water evaporation and drying of salt solutions in the oscillating flow of a continuous phase were carried out for a valved pulse combustor. Extensive experiments (PDA, LDA, temperature, noise, pressure measurements) to determine the inlet conditions and also to validate the model were performed for a horizontal pulse combustion dryer (Smucerowicz, 2000). Sinusoidal axial velocity oscillations have been defined as follows ... 

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