Objectives

  • To demonstrate the technical-economic viability of high-solids anaerobic digestion technology as an alternative in small to medium size WWTPs.
  • To increase sludge stabilization (i.e. Volatile Solids in the effluent between 40-60%).
  • To reduce transport costs by 30% approximately, and therefore environmental impact due to transportation, for example CO2 emissions. It has been considered that 0,225 kg CO2/km will be avoided.
  • To improve the quality of the sludge produced (i.e to reduce pathogen content). It is expected a reduction between 50-99% of pathogens.
  • To reduce 80% of reactor volume comparing to conventional wet digestion. A compact digester with higher volumetric organic loading rate would be used, and consequently less consumption of material resources will be necessary.
  • To reduce greenhouse gas emissions in sludge storage tanks due to the reduction of quantities of sludge generated and the process applied.
  • To increase resource recovery from organic matter as green energy: the biogas produced contributes to the energy self-sufficiency of wastewater treatment plants. At the same time, there is a reduction of fossil fuel consumption regarding the initial situation of this type of WWTPs without sludge stabilization.
  • To promote the inorganic fertilizers substitution (by 70% approximately) due to the use of recycled sludge in agriculture and reduction of carbon emissions associated to its use in agriculture.