Views:0 Author:Site Editor Publish Time: 2020-03-19 Origin:Site
The plate evaporator is a new type of high-efficiency energy-saving evaporation equipment developed in recent years. Compared with the traditional tube evaporator, it has the following characteristics:
(1) The heat transfer efficiency is high, K value is generally 3500 ～ 5800kW / (m2 · K), which is 2 ～ 4 times higher than the shell and tube evaporator, so the heat transfer area is small under the same conditions;
2 (2) Compact structure and small size, especially suitable for the occasion of making full use of the original equipment, such as the renovation of old factories and technological transformation, to overcome space limitations;
3 (3) Light weight, thin heat transfer plate, less metal consumption, about 10 kg of metal per square meter of heating area, only 1/3 ～ 1/4 of the tube-type heater;
(4) The residence time of the heating material in the heater is short, the internal dead angle is small, and the sanitary conditions are good, which is suitable for heating the heat-sensitive materials;
(5) Flexible operation and large equipment allowance. You can increase or decrease the number of plates to change the heating area or change the working conditions according to the needs.The size of the equipment specifications is large. To 0.5m2, the largest can reach 1.3m2, and the heat exchange area of each device can be between 1 ~ 1000m2;
(6) A lower temperature heat source can be used to recover the heat in the low temperature heat source, and the heat transfer temperature difference between the cold and hot materials can be reduced to 4 to 5 ° C.
Due to rising energy prices and environmental protection requirements, the industrial demand for energy-saving equipment has grown rapidly. The research and application of plate evaporators have developed rapidly in recent years. Regardless of domestic and foreign, as a new type of energy-saving evaporation equipment, plate evaporator has been widely used in metallurgy, food, paper, air conditioning, chemical and desalination industries. This paper introduces the application status and related progress of plate evaporators in various industries in recent years by consulting a large number of domestic and foreign literature, including the literature on the vacuum technology website.
2. Application of plate evaporator in metallurgy and mining industry
The concentration of thorium solution is an important process in metallurgy and mining industry, and it is also a process with high energy consumption. The evaporator is a traditional solution concentration equipment.It is generally divided into four forms: natural circulation, forced circulation, rising film, falling film, etc., of which the plate falling film evaporator is a new type of evaporator developed in recent years. The structure is shown in Figure 1. Compared with the traditional tube evaporator, it has the characteristics of low steam consumption and high production capacity, which is a direction for the future development of the evaporator.