fluidized bed drying
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The last edit to this post was made by sunjl1981 on 2013-1-6 at 23:44. Question: By reducing the temperature in the first few chambers of the vacuum drying bed and eliminating cooling in the latter chambers in order to cut steam consumption, can the product achieve a satisfactory moisture content? # ， ， &
The key is to ensure an appropriate retention time and suitable temperature; otherwise, it is difficult to achieve the desired level of moisture.
Air dehumidifiers can be used to reduce the moisture content in the air
It cannot pass. As the temperature in the preceding chambers decreases, the rate of water evaporation from the resin surface slows down, and the moisture gradient inside and outside the resin also decreases, which directly affects the removal of moisture from within the resin.
If we consider solely whether a qualified moisture content can be achieved? ”It can be said that by reducing the temperature of the first few chambers, it is possible to maintain an acceptable water content while simultaneously reducing steam consumption. However, other process parameters must be adjusted accordingly, such as increasing the bed height and extending the residence time of the material. In this case, the exhaust temperature will decrease, heat utilization will improve, and steam consumption will drop; yet there is a risk of reduced production volume. It is necessary to carefully adjust all parameters to ensure an adequate supply of heat. In fact, achieving a reduction in temperature while maintaining yield and moisture content is precisely the ideal state that drying equipment strives for.
Using a dehumidifier still requires heating the air in the end, consuming steam. It is not possible to achieve both ensuring proper moisture levels and reducing the steam consumption per unit of product. Personally, I believe that the moisture content of the material should be reduced to the lowest possible level through other methods (such as centrifugation) before it enters the fluidized bed.
Are there any existing PVC stripping technologies in China that utilize negative pressure at the top of the stripping tower?
The use of a dehumidifier can reduce steam consumption to some extent, as less heat is required in air-flow drying to facilitate water vapor evaporation; most of the heat is used to raise the temperature of the air and increase the unsaturation of the water content in the gas. Just as in cold winters, when the air is dry, clothes can be dried quickly. It can be verified through the corresponding heat and mass balance. If it is difficult to do so using mechanical methods (such as centrifugation), the costs such as electricity consumption will increase.