Batch Size Adjustment

The control system requires the values of T and AT obsei-ved during the first minutes of operation to be stored as the basis for the above calculation of end point. When the exhaust temperature then reaches the value calculated, diying is terminated. Coefficient K can be estimated from models but requires adjustment on-hne to reach product specifications repeatedly. Products having different moisture specifications or particle size will require different settings of K, but the system does compensate for variations in feed moisture, batch size, air moisture, and inlet temperature. Some exhaust air may be recirculated to control the dewpoint of the inlet air, thereby consei-v-ing energy toward the end of the batch and when the ambient air is especially diy. 

Three different batch sizes were used, namely =400, =800, respectively =1200 kg in the chemical industry it is standard practice to validate a process for the available kettles and then adjust the particular batch size (minimum filling so the stirrer bar remains covered, maximum filling so no overpressure occurs and vents stay free) to achieve the requested tonnage often, campaigns of batches are run before the equipment is cleaned and refitted for the next product, see batch numbers 19. .. 23, followed by 1,. ... ... 

Therefore, even a moderate error in the mixer scale-up will have only a small effect on the agitator-side heat transfer coefficient. Other factors that include heat transfer area per unit volume are considerably more significant. For instance, in the jacketed tank, the heat transfer area per unit volume decreases upon scale-up. In order to assure the same proportionate heat removal or addition per unit batch size, additional heat transfer area (e.g., coils) may be required. Additionally, other variables such as temperature driving force may have to be adjusted to compensate for decreased heat... 

Citrate reduction. Chloroauric acid is boiled under reflux with sodium citrate (5) until the solution turns red. Particle sizes achieved are in the range of 15-150 nm, and a particular diameter is chosen for a batch by adjusting the amount of citrate added to the boiling flask. This method has been used, therefore, for producing probes in the larger particle size range. 

Direct labor (operators) Unit/ batch Production volume (adjusted for capacity requirements) or number of batches Linear Average batch size if number of batches used... 

Always allow for some material to remain on the inside of the container. A starting point is 5%. This should be cut back as experience is obtained. The adjusted batch size will be ... 

For a batch size of 5 L, 587.5 g (3.2 moles) of mannitol is dissolved in 3.5 L of water. Pamidronic acid (31.6 g, 0.133 moles) is mixed with a 1.0 L aliquot of the mannitol solution to form a slurry. The slurry is then transferred into the remainder of the mannitol solution, and stirred for at least 15 min. Aqueous 1 N sodium hydroxide (270 ml) is then added and the mixture is stirred until a clear, colorless solution results. The pH is then adjusted to 6.50.1 using either 1 M aqueous phosphoric acid or 1 N aqueous sodium hydroxide, as needed. The solution is then filtered through a 0.22 micron filter, and filled at 20°C into vials at 4.0 ml (4.172 g)/vial, under sterile conditions. The aqueous solution is frozen at -37°C and lyophilized (20 mbar, 20°-40°C) to yield 1,250 vials, each containing 30 mg of amorphous disodium pamidronate. The vials are sealed under positive nitrogen pressure. The disodium pamidronate is amorphous (noncrystalline) by X-ray diffraction and contains 0.7 wt-% water. 

A BPI is developed for a given batch size or a range of batch sizes of a standardised preparation. The formulation has been investigated in advance and the method of preparation has been validated. This means that data are collected and reviewed beforehand to ensure that each batch subsequently prepared will possess the required quality. The preparation method as described in the BPI is therefore only valid for the specified minimum and maximum batch size. The selected batch range depends on the equipment and materials used. Automated preparation documentation systems calculate the quantities to be processed when the batch size is adjusted. In the manual mode, for each batch size within the batch range a separate BPI has to be created. Before the preparation of a specific product is started, whether for the first time or after a change, the responsible pharmacist authorises the BPI and subsequently it is released for use. 

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