Energy recovery in wastewater treatment systems through hydraulic micro-machinery. Case study




efficiency, sustainability, recovery systems, Pump working as turbines (PATs)


The wastewater treatment plants (WWTP) treat the water from domestic and industrial use so that its discharge, once it passes through them, is harmless to the environment. However, large amounts of energy are necessary to carry out this process. Therefore, energy and process optimization are a key issue within these type of plant. One of the possibilities within the WWTPs is the recovery of hydraulic energy. This paper presents alternatives for the recovery of hydraulic energy, through the use of hydraulic micro-machinery such as PATs or hydrostatic pressure wheels. This type of machinery is capable of recovering a part of that energy that until now it was not possible to recover, in a more economical way and assuming an improvement for plants that have the possibility of installing it. In the here described case study, savings of over 4% were achieved with periods of return on investment of less than 5 years.


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Author Biographies

Rosa Llácer-Iglesias, Universitat Politècnica de València

Dpto. de Ingeniería Hidráulica y Medio Ambiente

Jose M. Pérez, Universitat Politècnica de València

Dpto. de Ingeniería Hidráulica y Medio Ambiente

Jose Ricardo Satorre-Aznar, Universitat Politècnica de València

Dpto. de Ingeniería Hidráulica y Medio Ambiente

P. Amparo López-Jiménez, Universitat Politècnica de València

Dpto. de Ingeniería Hidráulica y Medio Ambiente

Modesto Pérez-Sánchez, Universitat Politècnica de València

Dpto. de Ingeniería Hidráulica y Medio Ambiente


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