Steam condensate preheating and steam drying two-stage energy-saving sludge drying method

Abstract

The invention relates to a steam condensate preheating and steam drying two-stage energy-saving sludge drying method. The method comprises the following steps: (1) driving wet sludge into a sludge preheater to be indirectly contacted with steam condensate obtained by steam drying to form preheated wet sludge and condensation water respectively, (2) continuously and uniformly adding the preheated wet sludge into a drier, allowing saturated steam or superheated steam to enter the drier at the same time to form dry sludge, high-temperature condensate and smelly high-humidity tail gas, (3) allowing the high-temperature condensate to enter a condensate tank, and enter the sludge preheater through a condensate pump to preheat the wet sludge, (4) after dedusting the smelly high-humidity tail gas with a duster, obtaining sludge powder and high-humidity tail gas respectively, allowing the sludge powder to return to the drier through a rotary discharger, and (5) allowing the high-humidity tail gas to enter a condenser for cooling and condensation, and obtaining cooling return water, sewage and tail gas respectively after heat exchange. The method can effectively improve steam heat utilization efficiency.

Description

technical field [0001] The invention relates to the technical field of sludge drying and energy saving and consumption reduction, in particular to a two-stage energy-saving sludge drying method of steam condensate preheating + steam drying. Background technique [0002] In the existing sludge drying industrial installations, the drying equipment mostly adopts conduction heat transfer dryers such as disc dryers, paddle dryers, and film dryers. After the sludge is dried, steam condensate is obtained. Generally, steam The pressure of the condensate is 0.5~0.6MPa, the temperature is 158~164℃, the temperature of the steam condensate is high, the sensible heat of the steam condensate is not fully utilized, the steam heat utilization rate is low, and the drying process is relatively inefficient. Contents of the invention [0003] The technical problem to be solved by the present invention is to provide a two-stage energy-saving sludge drying method of steam condensate preheating ...

AI Technical Summary

Problems solved by technology

[0002] In the existing sludge drying industrial installations, the drying equipment mostly adopts conduction heat transfer dryers such as disc dryers, paddle dryers, and film dryers. After the sludge is dried, steam condensate is obtained. Generally, steam The pressure of condensate is 0.5~0.6MPa, the temperature is 158~164℃, the temperature of steam condensate is high, the sensible heat of steam condensate is not fully utilized, the utilization rate of steam heat is low, and the drying process is relatively inefficient

Images