Drying humid material e.g. sludge from waste water treatment/compost using air as coolant fluid operating in circuit, by preheating material, introducing fresh air into circuit for circulation, and heating part of air using solar collector

摘要

The process comprises preheating a humid material, introducing fresh air into a circuit for circulation, heating a part of the air using a solar collector or a heating unit (3), controlling a part of the circulating flow flowing in between the preheating and heating, drying the humid material by convection drying, releasing air out of the circuit, carrying out a heat exchange process between the air before drying and the air after drying to heat additional air before drying, cooling the air after drying, and filtering the air after drying by a hydrophobic ultra porous solid adsorbent. The process comprises preheating a humid material, introducing fresh air into a circuit for circulation, heating a part of the air using a solar collector or a heating unit (3), controlling a part of the circulating flow flowing in between the preheating and heating, drying the humid material by convection drying, releasing air out of the circuit, carrying out a heat exchange process between the air before drying and the air after drying to heat additional air before drying, cooling the air after drying, filtering the air after drying by a hydrophobic ultra porous solid adsorbent such as a zeolitic material of powder form in a fluidized bed, carrying out a secondary drying by conduction, and returning the air collected in upstream of the circuit. A heating pipe is placed downstream of the heating unit. An independent claim is included for a device for drying a humid material.