BRONI WWTP

MBBR

technology

Water Technologies Italia S.p.A.

Context

BRONI

� Upgrading & refurbishment

� From Carbon to Nitrogen Removal� 15 mg/l TN

� 25 BOD

� 15 SS

� 17.500+35.000 P.E.� 3.100 kg/BOD/d

� 624Kg TN/d

� 104 kg P/d

� 3.120 kSS/d

� Flow rate (extension)� DWF avg = 7.000 m3/d

� WWF peak = 750 m3/h

� Tender: 5,1 M€

BRONI: existing WWTP

CASCAS

� Coarse screening

� Pumping station

� Fine screening

� Sand and fat/grease

removal

� Pre-aeration

� Primary clarification

� CAS ( 2 lines)

� Final clarification ( 2 lines)

� Final disinfection

BRONI: block diagram final solution

CASCAS

refurbishmentrefurbishment

MBBRMBBR

New New lineslines

� Coarse screening 30 mm

� Pumping station

� Storm tank

� Flow repartition

� Fine screening 3 mm

� Sand and fat/grease removal (2

lines)

� MBBR Biological reactor (2

� Fine screening step screen - 3 mm (new)

� Sand and fat/grease removal (1 line -

existing)

� Anoxic selector & P removal (1 line – ex lines)

� Pre-DN

� Carbon removal

� Nitrification

� Final clarification & P

removal (2 lines)

� Coagulation

� Flocculation

� Lamella clarifiers

� Anoxic selector & P removal (1 line – ex

pre-aeration)

� Pre-denitrification (1 line - ex-primary

clarification)

� Nitrification ( 2 lines – existing CAS)

� Final clarification ( 2 lines - existing)

� Pumping station (ex disinfetion)

� Filtration – DiscFilters 10 micron

� UV Disinfection

� Sludge static thickening

� Sludge dewatering

BRONI: original solution

CASCAS

BRONI: final solution

CASCAS MBBRMBBR

MMBR genaralities

� Bilogical treatment with

fixed film biomass for

nitrogen and carbon

pollution removal

� Supporting media is freely

moving in the reactor

Pure MBBR� Suspended biomass activity

negligible

� Most compactness

� Better oxygen transfer efficiencies

MBBR: biofilm

”biofilm is bacterial colonization, fixed on a

inert (plastic) support thanks to their

extracellular product (EPS)”

MBBR: support

PROTECTED SURFACEPROTECTED SURFACE

MBBR: biomass selection

PrePre--DenitrificazioneDenitrificazione

Rimozione CODRimozione CODNitrificazioneNitrificazione

K5

Plant general data

Existingrefurbished

MBBRnew line

Capability 17.000 P.E 35.000 P.E

Pre-denitrification 200+1.650 m3 2x750 m3

2 x 240 m3 K5

C-removal n.a. 2x270 m3

2x90 m3 K5

Nitrification 2.200 m3 2x650 m3

2x215 m3 K5

Air flow rate 4.400 Nm3/h 1.200+4.600 Nm3/h

Clarifier 450+200 m2 2x53 m2Clarifier 450+200 m2 2x53 m2

Common units

Storm tank 3.500 m3

Filtration DiscFilters 18 micron

n. 1 Unit – 750 m3/h peakDia 2200 mm x 22 disk

UV Disinfection n. 1 Unit – 750 m3/h peak3 modules – 8 lamps – 254

nm

Sludge static thickening Dia. 12 m. – 450 m3

SRT 2,2 d – 25 kgSS/m2/d

Sludge dewatering 44 h/week – 18 m3/hFrom 0.9 to 25 % SS

Solids and Phosphourus removal

Coagulation: electrical forces neutralization - Iron Chloride

Phosphorus removal: conversion soluble OrthoPhosphate

into IronPhosphate, not soluble

Flocculation: particle agglomeration into large flocs –

Polymer

Lamella clarifiers for high rate sedimentation: mirror speed

> 5 m/h.

Final filtration

ALGHERO

STRADELLA

Final UV disinfection

< 5.000 MPN/100 ml < 5.000 MPN/100 ml –– Escherichia Coli = new UV configurationEscherichia Coli = new UV configuration

Sub-vertical lamps

Higher compactness

Bioassay validation

Easily removable lamps, one by one, for a more efficient maintenance

Automatic cleaning without operation stops

Some pictures

BRONI: the plant