tertiary wastewater treatment for reuse in irrigation … · tertiary wastewater treatment for...
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Tertiary wastewater treatment for reuse in irrigation and groundwater recharge in Fasano
(Apulia, Italy)
Alfieri POLLICE
Strongly ruralRuralModerately ruralUrbanStrongly urban
Rainfall (1960-2010)
Puglia: 600-650 mm/year136 m3/capita per yearabsence of permanent rivers/natural lakes
Cultivated 79%
Irrigated 19%
Other 21%
Land use
Puglia – Available water and land use
Groundwater salinity concentration in central-southern Apulia(from measurements of water electrical conductivity in 120 wells)
FasanoBari
Wastewater treatment and effluent reuse
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200
400
600
800
1000
1200
Agricultural Civil Industrial
Destination
Con
sum
ptio
n (M
m3 /y
)
External Resources (border regions) Regional Resources (groundwater)
Total Regional Water demand
1500 Mm3/y
Municipal wastewater potentially available for reuse in irrigation: • Total estimate 150 Mm3/year• Tertiary wastewater treatment plants currently available 90 Mm3/year
Further advantages:• Nutrient recovery• Continuous supply
Water demand in PugliaSavings on primary resources = 10%
Regional Water Plan of Puglia (2007)
Opportunities of reuse for irrigation in Puglia
Treated wastewater reclamation in Fasano (Apulia)
Contexto Wastewater treatment plant: 25.000 PE (6000 mc/d);o Effluent discharge to the sea (on shore);o Intensive horticulture area (+ olive trees and vineyards);o Groundwater overexploitation lead to seawater intrusion (> 5g/L NaCl)
First tertiarytreatment plant(2005-2016)
• Simultaneous dosing and mixing:1.Sodium hypochlorite NaClO (pre-disinfection)2.Aluminum chloride AlCl3 (coagulant)3.Activated carbon and zeolite (adsorbent)
• Sedimentation / Contact basin (3000 mc)• Post-disinfection UV
Treated wastewater reclamation in Fasano (Apulia)First tertiary treatment plant (2005-2016)
Post-disinfection UV = 800 mc
Q= 200 mc/hDose = 25 mJ/cm2
The irrigation network
Treated wastewater reclamation in Fasano (Apulia)
• Total surface served: 1500 hectares• 30 km piping• 51 farms contracted• 350 hectares irrigated
Treated wastewater reclamation in Fasano (Apulia)First tertiary treatment plant (2005-2016)
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
Objectives• Zero discharge;• Reuse in irrigation and groundwater recharge;• Environmental restoration (park, recreational, bird settlement, etc.)• Test new proprietary technology (patent pending).
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
New technological configuration (MITO3X® patent pending)1. Simultaneous injection of:
• AlCl3 (clariflocculation)• NaClO or PAA (disinfection)• PAC (adsorption)
in the suction line of a centrifugal pump.The pump rotating parts provide intensive mixing of the dosed compounds.2. Lamellar packs settlers.
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
Multipurpose systemStorage, stabilization and naturalization basin of 40,000 mc for compensationof the demand variability from farmers.The basin is equipped with an overflow system for groundwater rechargethrough surface spreading (in trench).
Different uses of the produced water• Irrigation according to farmers demand (R1)• Environmental restoration, recreational activities, bird settlement, etc. (R2)• Groundwater recharge and contrast to seawater intrusion (R3)
R1+R2+R3 = Total effluent recovery and zero discharge
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
Other featuresAutomated monitoringMain parameters in the influent (secondary treated wastewater) and producedwater are monitored in real time.
Sludge handlingThe solid fractions resulting from the lamellar settlers are sent to dewatering beds and then to recovery or storage sites.
Cost issuesTertiary treatment cost is0.16-0.25 €/m3, and it iscovered by the water bill.Distribution cost dependson distance, type of irrigation and volumes, and it is payed by the farmers.
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
First results
In the period July-September 2016 the plant produced about 250,000 m3
of water within the national standards for reuse.
Real time monitoring Sampling and lab analyses
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
Rural landscape and productivity improvements
Before and after: integration of horticulture with the traditional olive yards
Treated wastewater reclamation in Fasano (Apulia)Treatment plant upgrade (2016)
Environmental aspects and recreational activities
