Principles of Tray Dryer A tray dryer operates on the principle of convection drying, where heated air circulates over the trays containing the wet material. The moisture from the material is transferred to the air and carried away, leaving the material dry. Construction of Tray Dryer Chamber: An insulated enclosure to maintain heat. Trays: Perforated … Read more
The “rate of drying curve” is a graphical representation used in drying processes to illustrate how the moisture content in a material change over time. This curve is important in various industries such as food processing, pharmaceuticals, and materials science for optimizing drying techniques and understanding the kinetics of moisture removal. Rate of Drying Curve … Read more
Principle of Steam Distillation: It is used to distil heat-sensitive components by passing steam through the mixture, causing volatile components to co-distil with water at temperatures lower than their boiling points. Methodology of Steam Distillation: Setup: Includes a steam generator, distillation flask, condenser, and collection vessel. Steam Introduction: Steam is introduced into the mixture, lowering … Read more
Principle of Fractional Distillation: Fractional distillation separates components of a mixture with close boiling points by using a fractionating column to achieve repeated condensation and vaporization cycles. Methodology of Fractional Distillation: Setup: Similar to simple distillation but includes a fractionating column between the distillation flask and the condenser. Heating: The mixture is heated, and vapours … Read more
Principle of Molecular Distillation: Molecular distillation is a type of vacuum distillation performed at extremely low pressures, allowing the distillation of high molecular weight, thermally unstable compounds. It involves a short path between the evaporator and the condenser. Methodology of Molecular Distillation: Setup: Includes a high vacuum system, short-path distillation apparatus, and a cold trap. … Read more
Principle of Vacuum Distillation: Distillation under reduced pressure (vacuum distillation) lowers the boiling points of the components in the mixture by reducing the ambient pressure, allowing distillation to occur at lower temperatures. Methodology of Vacuum Distillation: Setup: Similar to simple or fractional distillation but includes a vacuum pump to reduce the pressure in the apparatus. … Read more
Economy of Multiple Effect Evaporator: Defined as the amount of steam required to evaporate a given amount of water. Steam Economy = kg of water evaporated / kg of steam used. In a single-effect evaporator, the steam economy is approximately 1. In multiple effect evaporators, the steam economy improves significantly, often reaching values of 3-6, … Read more
Principle of Multiple Effect Evaporator: Utilizes the vapor produced from one effect (stage) to heat the next effect, thus reusing energy and improving overall efficiency. Construction of Multiple Effect Evaporator: Effects (Stages): Multiple evaporators connected in series. Heat Exchangers: In each effect where the liquid is heated. Condensers: To condense the vapor from each effect. … Read more
Principle of Forced Circulation Evaporator: Uses mechanical pumps to circulate the liquid through the evaporator, enhancing the heat transfer rate and preventing fouling and scaling. Construction of Forced Circulation Evaporator: Heat Exchanger: Typically, a shell and tube design where the liquid is heated. Circulation Pump: Forces the liquid through the heat exchanger. Evaporator Body: Where … Read more
Principle of Simple Distillation: This distillation separates components of a mixture based on differences in their boiling points, typically when the boiling points differ significantly (more than 25°C). Methodology: Setup: Consists of a distillation flask, a heat source, a condenser, and a receiving flask. Heating: The mixture is heated in the distillation flask. Vaporization: The … Read more
