Steps in Energy Saving

By neglecting the heat contribution of the product, the heat recovery efficiency coefficient is 

The optimum temperature 3 and, therefore, the most favorably achieved temperature and maximum heat recovery efficiency coefficient //, result from minimizing the total costs of the heat recovery and gas heater [5.25]. 

DR Dryer GH Gas heater HR Heat recovery BL Blower FG Fresh gas EG Effluent gas HG Hot gas HA Heating agent WP Wet product DP Dry product 

R Fresh gas preheating by heat recovering R... V Fresh gas heating in the gas heater 

According to Fig. 5-20, a convection drying unit may also be combined with a heat pump cycle [5.27). Waste gas leaving the dryer releases heat at a low temperature level 7, to the vaporizer of the heat pump in which the gas loses moisture. In the condenser, the drying gas absorbs heat Qff at a higher temperature level Th and flows back to the dryer. The rating e of the heat pump, including the compressor power Ny, is 

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