Method for back mixing and drying of viscous sludge by comprehensively utilizing mud cakes and device

The invention discloses a method for back mixing and drying of viscous sludge by comprehensively utilizing mud cakes and a device. The method comprises the following steps of adding a deodorizing bactericide and mud cake particles with the moisture content of 45-50% and the particle size of 0.1-2mm into viscous sludge with the moisture content of 78-82%; and drying under natural condition after sufficiently stirring and mixing. The invention also discloses the device for realizing the method. The device comprises a first spiral conveyer, a mixing stirrer, a second spiral conveyer and a layered sun drying field which are sequentially connected through pipelines, wherein a feeding hole for adding the viscous sludge and the deodorizing bactericide is formed in the first spiral conveyer; and a charging hole for adding sludge particles is formed in the mixing stirrer. The method has the beneficial effects that the odor content is low in the drying process, the drying efficiency is high, and the energy consumption caused when the centrifugally dehydrated sludge is secondarily dried is reduced through sun drying. No large infrastructure constructions are matched so that the disposable investment cost is low; and the method is particularly suitable for in-situ treatment, capable of avoiding sludge transportation cost and high in daily processing capacity.