Tumbler dryer

Aftertreatment Main products are fabric softeners (->quaternary ammonium compoimds). Starch formulations, used to stiffen the final fabric, are more and more substituted by synthetic polymers. Laundry dryer (tumbler) aids are nonwoven materials that are impregnated with softener and temperature-resistant fragrance oils or sprays based on these materials. 

TABLE 9.7. Performance of Agitated Batch Dryers (See Fig. 9.7) (a) Double-Cone Tumbler ... 

After a final rinse with clean water in tumbler washers, the cork moisture levels arc adjusted to 5.5 to 8% in continuous tunnel dryers to avoid growth of microorganisms on the washed corks. An ideal moisture level achieves a water activity unsuitable for mold growth, yet high enough to maintain the flexibility of the cork necessary for bottling. 

Tumbler Vacuum Dryer. This dryer is designed for drying of chemical, pharmaceutical products which are not sticky. Its double cone rotating shape ensures direct contact between the material and the heated surface, resulting in uniform heat transfer. 

In a tumbler dryer, free-flowing products are dried under vacuum. Through a shift in the axis of rotation and the vessel axis, the jacket-heated drying vessel has a tumbling motion. The product inside the dryer follows this motion due to gravitational forces... 

FIGURE 53.3 FOB costs (US, in the year 2000) vs. dryer volume in of selected dryers according to Equation 53.5 1, atmospheric cabinet dryer (aluminum) 2, vacuum cabinet dryer (aluminum) 3, spray dryer fully equipped (304-stainless steel) 4, steam tube rotary dryer (carbon steel) with instrumentation 5, vacuum dryer with unheated agitator (304-stainless steel) 6, double-cone tumbler dryer (304-stainless steel). 

After washing, the excess water is pressed from the laundry and it is transported via a conveyor belt to a tumbler (not a tumble dryer) to separate the washing items from eaeh other. The samples that were only washed were loaded direetly back into the washing-machine, while the samples that were also tumble dried were transported to the tumble dryer. 

Deans, J. The modelling of a domestic tumbler dryer. Applied Thermal Engineering, 2001,21(9) 977-990. 

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