With a wide range of engineering plastics are used, desiccant-type dryer has been gradually replacing the traditional hot air dryer (oven). Use dehumidifying dryer has the following four benefits: 1, can be taken away by the water in plastic material to eliminate air bubbles, so that products achieve the desired mechanical properties, electrical resistance, dimensional stability and
With a wide range of engineering plastics are used, desiccant-type dryer has been gradually replacing the traditional hot air dryer (oven). Use dehumidifying dryer has the following four benefits:
1, can be taken away plastic raw materials in the water to eliminate air bubbles, so that products achieve the desired mechanical properties, electrical resistance, dimensional stability and appearance neat and beautiful.
2, to prevent the generation of defective products and return loss, greatly reducing the generation of waste.
3, because the desiccant dryer is to use very dry air to be dehumidified work, it can shorten the drying material time, save time.
4, desiccant dryer air circulation system piping are sealed and fitted with filters, so the climate impact from outside, as well as in the factory to prevent dust pollution, improve the working environment.
How to achieve maximum drying efficiency?
A good drying efficiency determinants of the following four points: drying temperature (Drying Temperature), drying time (Residence time), air volume (Air flow), dew point (Dew point). And a chain of these four factors, any one of the conditions change will affect the drying effect.
The drying temperature (Drying Temperature) is the temperature of the air into the drying tub, a raw material for each of its properties, such as molecular structures, specific gravity, specific heat, moisture and other factors, the drying temperature has a certain limit, the temperature is too high Some of the additive material causes deterioration or agglomeration volatile, low and cause some of the crystalline material can not achieve the desired drying conditions, such as: PC/120 ℃, ABS/80 ~ 95 ℃. Also in the choice of dry barrel heat insulation is required in order to avoid dropout drying temperature, drying temperature resulting in inadequate or waste of energy.
Drying time (Residence time) is pre-dried before molding material time, drying time is too long will cause deterioration or caking of raw materials or waste energy, the drying time is too short will cause the phenomenon of high moisture content. For example: PC/3-4 hours, ABS/3-4 hours.
Air flow (Air flow) is the raw material moisture away only medium, the air volume will affect the quality of dehumidification effect. Air flow might cause the return air temperature is too high, resulting in overheating (over heat) and affect the stability of the dew point of the air volume is too small the water in the raw material can not be completely removed, the wind also represents the desiccant dehumidifying capacity.
Dew point temperature (Dew point) is that when the gas is cooled to the moisture condenses into water droplets containing the temperature is a measurement gas drying (wet) level of the unit. The less moisture in the gas, the lower the dew point temperature. Good desiccant dryer dew point to be able to reach the dew point temperature of -40 ℃.
The use of desiccant dryer can be divided into standalone and centralized, single DEHUMIDIFER usually include drying machine host, dry barrel, suction machine. Stand-alone use for a small variety of drying, the drying efficiency advantage is good, fast and easy refueling. Centralized dryer including a dryer drying hosts and several barrels, each drying tub has a separate heating controller, can drying of several different materials, and with the air flow regulating valve to control the air volume of each drying tub.
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