Sludge incineration

Bio-solids like municipal sludge, industrial sludge and fine solids can be incinerated with the advantage of eliminating the sludge. Energy from the incineration process can be recovered as green energy source.

Depending on their calorific value of the sludge being incinerated, pre-drying of the sludge and pre-heating of the combustion air may be necessary.

Thermal destruction of sludge

Landfill or agricultural use of wastewater sludge is not always a feasible solution. The better the wastewater treatment process, the more noxious, or dirtier is the sludge.  Incineration is a safe way of turning a problem waste into an opportunity.

Mechanically dewatered sludge cannot be incinerated auto thermally, i.e. reaching a temperature above 850°C without the use of auxiliary fuel. Auxiliary fuel is a big operational cost and thus is to be avoided. That is why it is necessary to increase the %DS before incineration.

The thermal destruction process of sludge consists of two steps:

  1. Sludge drying in order to increase the %DS.
  2. Sludge incineration of the pre-dried sludge.

Heat recovery

Sludge drying is a heat consuming process, whereas sludge incineration produces heat. In integrated sludge treatment both processes are designed so that the heat required for drying (HYDROGONE® horizontal disc dryer and PUTTART® vertical drier granulator) is recovered from the heat released by the sludge incineration (HELIOSOLIDS® fluidized bed incinerator)


A wide range of separate or mixed injected sludge and waste streams can be incinerated with or without support fuel, depending on their heating value.

  • Industrial sludge like oily sludge and slurry
  • Spent grains from the brewing industry
  • Acid oils


  • Safe alternative for landfill
  • Total elimination of sludge excess
  • Energy recovery


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