Disposal alternative |
Advantages |
Disadvantages |
Incineration
|
Drastic volume reduction Sterilization
Energetic valorization of sludges
Low sensitivity to sludge composition
Minimization of odors, due to closed systems and high temperature
|
High costs
Ash disposal
Atmospheric pollution
|
Landfill disposal
|
Low cost
|
Problems with locations near urban centers
Gas and landfill leachate production
Difficulty in reintegrating the area after decommissioning
Requirement of large areas
Requirement of special soil characteristics
|
Thermal drying
|
Total destruction of organic matter and total mineralization of sewage
sludge
The possibility of burning both stabilized and unstable sewage sludge
Up to 10-fold reduction of sludge volume
Energy recovery
No odor emission
|
Large investment cost, high operating costs
Energy consumption of the installation
The necessity of using pre-dried, dehydrated sediments;
Emission of dusts, gases (SOx, NOx,
HCL, HF)
The need to store the resulting ashes
|
Composting
|
The possibility of burning both stabilized and unstable sewage sludge
Sewage sludge mass and volume reduction
Sludge water content reduction
The product can be used as a fertilizer as it contains nitrogen,
phosphorus, potassium, and microelements, and it improves soil
properties
Easy operation of the installation
|
Windrow and aerated static pile composting require relatively large
areas, and odor control is a common problem
Ambient temperatures and weather conditions influence windrow and
aerated static pile composting
In-vessel reactors have limited flexibility to handle changing
conditions and are maintenance intensive
|
Agricultural reuse
|
Large area availability
Potential as a fertilizer
Positive effects for the soil
Positive outcome for the crops
Long-term solution
|
Contamination of the soil by metals
Odors
Limitations regarding composition and application rates
Food contamination with toxic
elements and pathogenic
|