Sludge viscosity reduction drying method

Abstract

The invention relates to the technical field of sludge drying, and in particular, relates to a sludge viscosity reduction drying method. The method provided by the invention comprises the following steps: carrying out pre-dehydration on sludge to obtain sludge with the water content of 75%-85%; carrying out contra-rotating extrusion on the sludge with the water content of 75%-85% through a heatingroller, to obtain sludge with the water content of 40%. The heating roller comprises a heating roller body and a Teflon coating layer on the surface of the heating roller body; the temperature of theheating roller is 145 to 155 DEG C; the temperature of the heating roller is achieved in a steam heating mode. According to the method, the wall sticking effect generated during indirect drying of the sludge is avoided, the heat transfer resistance is reduced, the drying efficiency is improved, and the potential safety hazard of drying equipment is reduced.

Description

Technical field [0001] The invention relates to the technical field of sludge drying, in particular to a method for sludge reduction and drying. Background technique [0002] At present, in the chemical, pharmaceutical, food processing and textile industries, there is a problem of material sticking to the wall. The problem of material sticking to the wall during the drying process not only increases the heat transfer resistance during drying, reduces the drying efficiency, but also causes the safety of the drying equipment Hidden dangers. [0003] The moisture content of the sludge after mechanical dewatering and concentration is still high, as high as about 80%. Its transportation and treatment are difficult, so the sludge needs to be thermally dried to a certain moisture content. In the thermal drying of sludge, because the undried sludge contains a certain amount of organic matter and other sticky substances, the phenomenon of sludge sticking to the wall often occurs during th...

AI Technical Summary

Problems solved by technology

[0006] In the existing sludge drying methods, most of the drying methods are to directly contact the heating medium with the sludge. These methods not only consume a lot of energy, but also produce a large amount of tail gas that contains various components. Some types of sludge are easy to dry when they are directly dried. produce harmful and poisonous gas

The indirect drying of sludge is prone to sticky wall effect, causing problems such as equipment blockage, high energy consumption, and even safety accidents

In comparison, the cost and environmental pollution of indirect drying of sludge is lower than that of direct drying, but the sticky wall effect produced by indirect drying of sludge is a difficult problem to solve in indirect drying treatment technology

Images