Client: Junta de Extremadura

Year: 2019

Location: Mérida

Mérida WWTP was sized for a maximum population of 115,000 equivalent inhabitants and a maximum flow of 25,500 m3 / d, and was put into operation in 1996, so that practically all the processes and facilities have already reached the end of its useful life. The current equivalent population treated in the WWTP is around 60,000-70,000 equivalent inhabitants, with a daily flow of about 15,000 m3 / d. After checking the facilities, it was determined that the processes that needed more urgent action are those integrated within the pre-treatment building, reagent dosage and sludge dehydration, as this building presents a serious structural deterioration due to the corrosivity of the hydrogen sulfide present in environment.

The final drafting of the project focused on the following actions:

• New collector and pumping of raw water from the El Prado industrial park.
• New input of the two outfalls from the Wastewater Pumping Station.
• New sieving for the entire incoming flow until a dilution of 5 Qm.
• New grit-degreasing for a flow equivalent to 5Qm
• New measurement and regulation of flow to biological treatment.
• New sludge thickener
• New sludge dewatering
• New equipment for filtration, disinfection and pumping of industrial water.
• Dosing of sodium hypochlorite for disinfection and of ferric chloride for chemical sludge precipitation.
• Pretreatment and dehydration deodorization.
• New electrical equipment for the processes described above.
• New control and automation center that integrates the new equipment with the current biological control system and external WPS.