Sewage Water Energy Recovery
The modern
sewage water treatment plants (SWTP) are equipped with a biological
treatment process that generates a secondary product, sludge,
which contains most of the organic and contaminating elements
that have been removed from the water.
Since January 1999, Spanish law has forbidden the dumping
of sludge into the sea or rivers and consequently this requires
the purifying plant working procedures to be more efficient.
The Guascor Group has a self-developed technology for the
complete treatment of sludge with two lines of action:
- Use of energy from the biogas
- Thermal drying of the sludge
Energy generation from biogas
Guascor runs its engines with the biogas produced in the
anaerobic digestion of the effluent at the purifying plant.
The methane content of this gas reaches 65% - 75% and has
a calorific power between 5,000 and 6,000 kcal/nm3. Guascor
gensets transform this energy in electricity that is partially
used for self-consumption on the plant and the rest is exported
to the national grid with the resulting reduction in operation
costs.
Thermal drying of the sludge
The calorific energy coming off Guascor engines’
exhaust systems and cooling circuits is used to heat up
the sludge and the purifying plant’s digester.
The Guascor process offers direct, indirect or mixed drying
of the sludge minimizing emissions, reducing the initial
volume of sludge by 70% and achieving optimum performance
at the cogeneration plant.
Advantages of thermally drying sludge
- Drastic reduction in the volume of sludge (saving in transportation and distribution)
- Production of environmentally friendly energy –green energy-
- Valorization of organic material as a fertilizer
- Elimination of pathogens
