Pharmaceutics

The vacuum dryer is a viable technology used successfully for many years in the pharmaceutical, food, plastics, and textile industries. It is an indirect-heat dryer and best used for drying heat-sensitive materials at comparatively low temperatures. These materials are dried by applying a vacuum to evaporate the water or solvent. The use of vacuum lowers … Read more

(A) Batch Type fluidized bed dryer (i) Reverse turning bed type: In this FBD, by turning the air dispersion plate (the reverse turning bed) in 90° direction with the control motor, all the dried material can be discharged at once. (ii) Rotating discharge type: Dried material is discharged by opening the discharge gate equipped at … Read more

Fluidized bed dryer (FBD) is well known and widely used equipment in pharmaceutical manufacturing. It is used in the granulation process for drying the material to get desired moisture content in the granules or powders required for perfect compression of tablet formulation. Conventional fluidized bed dryers include batch fluidized bed dryer, semicontinuous fluidized bed dryer, … Read more

Spray Dryer: Spray drying is a method of producing a dry powder from a liquid or slurry by rapidly drying with a hot gas. This is the preferred method of drying of many heat-sensitive pharmaceuticals. A consistent particle size distribution can be achieved using spray drying of some industrial products such as catalysts. Principle of … Read more

The drum dryer has been used since a long time for drying sheets of paper or cloth and, more recently, for drying liquids and pastes. Drum dryers in general and the various types of drum dryers (atmospheric single drum, vacuum single-drum, and the double-drum dryers) in particular are selected or rejected for any given drying … Read more

Tray drying is a batch process used to dry materials that are liquid or wet cake. Tray drying works well for material that requires more gentle processing or cannot be atomized in an airstream due to viscosity. This dryer is well utilized for drying of wet products like crude drugs, chemicals, powders, or granules, etc. … Read more

Drying equipment is classified in different ways, according to design and operating features or based on the mode of operation, such as batch or continuous. In the case of the batch dryer, the material is loaded into the drying equipment and drying proceeds for a given period of time, whereas, in the case of the … Read more

Rate of drying When a wet non-porous granular solid material is placed in a tray and dried with a carrier gas like air under constant drying conditions of velocity, temperature, humidity, and pressure of air at the inlet, the experimental data can be plotted as drying rate vs. free moisture content or time, Shown in … Read more

Accurate percent moisture content is essential for maintaining the stability of drug products. If a product is too moist or too dry, it may not be suitable to be administered and will not exert the desired therapeutic effect. Most of pharmaceutical products contain moisture. The percent moisture content is seldom of interest. Rather, it shows … Read more

Equilibrium moisture content: The moisture contained in a material comprises all those substances which vaporize on heating and lead to a weight loss of the sample. The weight is determined by a balance and interpreted as the moisture content. As per this definition, moisture content includes not only water but also other mass losses such … Read more