Abstract: The present invention discloses a method of retreating a viscous semi-solid dewatered sludge having a water content of 70-85%, which is characterized by comprising the steps of: (1) adding a desiccant into said dewatered sludge, and stirring the resulting mixture to produce a mixed sludge having a water content of 50-60%; and (2) drying the mixed sludge to produce a dried granular sludge, which has a water content of 45% or less. The method of retreating the sludge of the present invention can decrease the treatment energy consumption, have a simple dry waste gas treatment, greatly reduce the cost for treating the sludge, accomplish the clean production and the sludge's innocuity, stabilization, minimization, and recycle.

Abstract: An air-drying device for sludge comprises at least one air-drying mechanism, a dosing mechanism, and a dehumidifying and heating mechanism. There two air-drying mechanisms. The dosing mechanism connects with the beginning end of the first air-drying mechanism (5) whose terminal end communicates with the beginning end of the second air-drying mechanism (8), with a discharge port (21) is arranged above the communicating position. The terminal end of the second air-drying mechanism communicates with the beginning end of the first air-drying mechanism to form a loop configuration. The device has high efficiency and low energy consumption. The detention time of the sludge in the drying device is adjustable so that the water content of the discharging material is adjustable.

Abstract: The present invention discloses a method of retreating a viscous semi-solid dewatered sludge having a water content of 70-85%, which is characterized by comprising the steps of (1) adding a desiccant into said dewatered sludge, and stirring the resulting mixture to produce a mixed sludge having a water content of 50-60%; and (2) drying the mixed sludge to produce a dried granular sludge, which has a water content of 45% or less. The method of retreating the sludge of the present invention can decrease the treatment energy consumption, have a simple dry waste gas treatment, greatly reduce the cost for treating the sludge, accomplish the clean production and the sludge's innocuity, stabilization, minimization, and recycle.

Abstract: A method of integration of concentration-dehydration and aerobic air-drying of sewage sludge comprises the following steps: (a) conditioning by an organic agent (3); (b) gravitationally concentrating (5) the residual sludge conditioned by the organic agent; (c) conditioning by inorganic agents (7); (d) mechanically dehydrating (8); (e) crushing and dispersing (10); and (t) aerobically air-drying (11).

Abstract: An air-drying device for sludge comprises at least one air-drying mechanism, a dosing mechanism, and a dehumidifying and heating mechanism. There two air-drying mechanisms. The dosing mechanism connects with the beginning end of the first air-drying mechanism (5) whose terminal end communicates with the beginning end of the second air-drying mechanism (8), with a discharge port (21) is arranged above the communicating position. The terminal end of the second air-drying mechanism communicates with the beginning end of the first air-drying mechanism to form a loop configuration. The device has high efficiency and low energy consumption. The detention time of the sludge in the drying device is adjustable so that the water content of the discharging material is adjustable.

Abstract: A method for drying sludge comprising the following steps: (a) Dry dehydrated sludge to obtain a carrier for drying sludge (6); (b) Transport the carrier for drying sludge (6) and dehydrated sludge to be dried (1) to a stirring and mixing apparatus (2) for stirring and mixing and thereby obtain mixed sludge; (c) Transport the mixed sludge (3) to a drying apparatus (4) for drying; (d) Repeat steps (b) and (c); characterized in that in said step (d) a portion of the mixed sludge (3) obtained from the stirring and mixing apparatus (2) which is in an amount determined by amount of sludge carrier (6) required for drying is extracted and transported to the drying apparatus (4) for drying and the rest of the mixed sludge is discharged as final product (7).

Abstract: A method for aerobically air-drying sludge cakes is provided. The method comprises: crushing and dispersing sludge filter cakes into a layer of sludge granules, blowing with positive pressure dry air into the layer of sludge granules moving at low speed or overturned so that the sludge granules experience aerobically exothermic reactions, which make moisture rapidly evaporated from sludge granules and moved to the dry air by mass transferring under the effect of both the external heat and internal heat, physically or chemically sterilizing the sludge granules moving at low speed or overturned, pumping out tail gas by negative pressure from the layer of sludge granules, washing and then discharging, and further pulverizing the dried sludge granules to reach the reclamation requirements. At the same time, an apparatus for carrying out the method is also provided. The method is high in heat conducting and mass transferring efficiency when drying and low in energy consumption for drying.

Abstract: A method of integration of concentration-dehydration and aerobic air-drying of sewage sludge comprises the following steps: (a) conditioning by an organic agent (3); (b) gravitationally concentrating (5) the residual sludge conditioned by the organic agent; (c) conditioning by inorganic agents (7); (d) mechanically dehydrating (8); (e) crushing and dispersing (10); and (t) aerobically air-drying (11).

Abstract: A method for drying sludge comprising the following steps: (a) Dry dehydrated sludge to obtain a carrier for drying sludge (6); (b) Transport the carrier for drying sludge (6) and dehydrated sludge to be dried (1) to a stirring and mixing apparatus (2) for stirring and mixing and thereby obtain mixed sludge; (c) Transport the mixed sludge (3) to a drying apparatus (4) for drying; (d) Repeat steps (b) and (c); characterized in that in said step (d) a portion of the mixed sludge (3) obtained from the stirring and mixing apparatus (2) which is in an amount determined by amount of sludge carrier (6) required for drying is extracted and transported to the drying apparatus (4) for drying and the rest of the mixed sludge is discharged as final product (7).

Abstract: A sludge concentration and dehydration method is provided, which comprises the following steps: (1) add an organic agent (polyacrylamide) to the sludge for initial conditioning, then concentrate the sludge; (2) add an inorganic agent (a compound containing Fe and Ca) to the sludge for further conditioning, then transport the sludge to a dehydrator for dehydration; (3) dispose the dehydrated sludge correspondingly when it satisfies the requirements for final disposal.