Coursework on "Single-hull evaporator unit"

Contents

Contents

Introduction

1 Current state of the evaporation process

1.1 Evaporator unit

1.2 Evaporators with natural circulation of solution

1.3 Evaporators with forced circulation of solution

1.4 Film evaporators

1.5 Multi-body evaporators

2 Development of equipment and process diagram of the unit

2.1 Description of the design of the designed apparatus

3 Design part

3.1 Determination of evaporator heat transfer surface

3.2 Determination of thermal insulation thickness

3.3 Determination of number of tubes

3.4 Barometric capacitor calculation

3.5 Calculation of vacuum pump capacity

Conclusion

List of sources used

Introduction

Evaporation is the process of concentrating solutions of solid non-volatile or small substances by removing the liquid volatile solvent. Evaporation usually occurs at reflux, i.e. under conditions where the vapor pressure above the solution is equal to the pressure in the working volume of the apparatus.

In industry, evaporation is usually carried out while boiling the solution

By evaporating solutions of solids in a number of food industries, saturation of the solution is achieved, with the further removal of the solvent from such a solution crystallization occurs, as a result of which the solute is released.

Evaporation is used to increase the concentration of dilute solutions or to isolate solute therefrom by crystallization.

The evaporation process is widely used in sugar and preservative production when concentrating sugar tomato juices, milk, etc.

In food technology, usually aqueous solutions are evaporated.

Evaporation is carried out in evaporators. The evaporation process can be carried out continuously and periodically. Transodic devices are used mainly in small scale industries.

Evaporation is carried out under both vacuum and atmospheric and excessive pressures.

Current state of the evaporation process

Heat exchangers - devices in which heat exchange between heating and heated media is carried out.

Various heat reactions can occur in heat exchangers: heating, cooling, evaporation, condensation, boiling, solidification and complex combined processes. Heat exchangers are used in almost all industries and, depending on the purpose, are called heaters, evaporators, condensers, regenerators, steam generators, reboilers, evaporators, etc.

Depending on the purpose of the production processes, a wide variety of gaseous, liquid and solid media can be used as heat transfer agents.

Installations consisting of a single apparatus of secondary steam, from which is not used (during evaporation under atmospheric pressure or during discharge) or used outside the apparatus, are called single-hull evaporators.

Multi-body evaporators are widely used, including several interconnected devices (housings) operating under pressure decreasing in the direction from the first housing to the last. Such installations may employ secondary steam generated in each previous housing to heat the subsequent housing. At the same time, only the first body is heated with fresh steam. The secondary steam generated in the first housing is directed to the heating of the second housing, in which the pressure is lower, etc., the secondary steam from the last housing enters the condenser or is used outside the installation.

Thus, multiple-body evaporators reuse the same amount of heat (heat supplied by heating steam in the first housing), thereby saving a significant amount of fresh steam consumed.

Conclusion

Developed evaporator unit for concentrated milk production plant.

The evaporator is designed for the production of concentrated milk, and can also be used in the evaporation of other liquid food media that are similar in thermophysical properties to milk. This unit is independent of the centralized steam supply line (boiler room, CHP) and includes the following elements: evaporator unit, steam generator, heater, condenser, tank equipment, supply pumps and vacuum pump.

The developed evaporator unit ensures the production of high-quality products due to the low temperature during evaporation, which ensures the safety of vitamins, coloring pigments and other valuable substances, at low energy costs. All this allows you to produce a high-quality product at low production costs.

Technical characteristics of evaporator:

capacity of the initial solution 4 m3/h;

heat transfer surface of the apparatus 160 m2;

heating steam flow rate 100 kg/h;

heating tubes 375 pcs

Выпарной ап 3200.dwg

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