experience with sustainable and cost-effective wastewater ... · experience with sustainable and...

ExperienceExperience withwith sustainablesustainable and and costcost--effectiveeffective wastewaterwastewater

treatmenttreatment usingusing aerobic aerobic granulesgranules

NeredaNereda®®

Aerobic Aerobic GranuleGranule TechnologyTechnology

DHVConsultancy and Engineering

- 4,700+ staff

- Markets• Aviation• Building and Manufacturing• Metal & Mining• Spatial Planning and Environment• Transportation• Water

- Services• Consultancy and advisory services• Design and engineering• Project and contract management• Operations management• Total solutions

Aerobic granulesCharacteristics:- Excellent settling properties- Pure biomass, no support media required- High biomass concentration- Simultaneous extensive biological N- and P-removal- Simple one-tank concept (no clarifiers)- Small footprint- Simple and easy operation- Sustainable technology- Low costs

activated sludge

aerobic granules

Instead of

use

Granules making up aerobic granular activated sludgeare to be understood as aggregates of microbial origin,

which do not coagulate under reduced hydrodynamic shear,and which subsequently settle significantly faster than

activated sludge flocs.

(First Aerobic Granule Workshop 2004, Munich, Germany)

Measurements:• fraction sludge > 0,212 mm•SVI5 and SVI30 comparable

Key advantages Nereda

- 75% smaller footprint:• high biomass concentration• no selectors, no anaerobic tanks, no clarifiers

Area Requirement (m2)

activated sludge with bio-P

Nereda

Courtesy Merle de Kreuk-TUD

Key advantages Nereda

- 75% smaller footprint:• high biomass concentration• no selectors, no anaerobic tanks, no clarifiers

- >25-35% energy savings:• less rotary equipment• efficient aeration

Area Requirement (m2)

activated sludge with bio-P

Nereda

Courtesy Merle de Kreuk-TUD

Key advantages Nereda

- 75% smaller footprint:• high biomass concentration• no selectors, no anaerobic tanks, no clarifiers

- >25-35% energy savings:• less rotary equipment• efficient aeration

Area Requirement (m2)

activated sludge with bio-P

Nereda

- lower construction & operation costs

Courtesy Merle de Kreuk-TUD

Increased sustainabilityIncreased sustainability-- Less energy consumptionLess energy consumption-- Improved water qualityImproved water quality-- Extensive nutrient removalExtensive nutrient removal-- Less construction materialLess construction material-- No chemicalsNo chemicals-- Less area consumptionLess area consumption

How to make granules?Selection mechanism:settling pressure and/or short decant phase

Nitrification (NH4 + O2 NOx )

P-removal/anoxic growth: (COD + NOx + PO4

3- N2 + CO2 + H2O + poly-P)

Heterotrophic growth (COD + O2 CO2 + H2O)

Oxygen gradient in granule enables simultaneous COD, P and N-removal

NeredaTM process

AeratonNitr / denitr / P-removal

AeratonNitr / denitr / P-removal

air air SettlingSettling

Fill / draw Fill / draw

effluenteffluent

influent influent

All processes in one reactor

Simple cycle

Short settling phase

Fill and draw combined

Continuous feed: multiple reactors or buffer tank

History- Research by Delft University of Technology (DUT) since mid ’90s - close co-operation DUT / DHV since 2000 - Stable granulation, extensive N- en P-removal in DUT lab (2002)- Feasibility study with great potential (2002)- Large pilot-research at Ede STP

(2003-2005)- Start-up industrial launching customer

(end 2004)- Industrial units (2006)- Design/construction municipal units

(2006/2008) 0,250,300,350,400,450,500,55

50.000 75.000 100.000 125.000 150.000 175.000

Annu

al Co

sts

Capacity

Nereda

LLAS

Set-up pilot Ede STP

VB + ZF

Bubbleaeration

Air-liftreactor

Bubbleaeration

Bubbleaeration

PC + SF

PC RD

FASE 1: Granulate formation

FASE 2: Optimised performance

PC + SF

Granule formation Ede STP

Definition: granule if d >212 µm

- natural selection of granules:

- increased start-up by use of granules

0%10%20%30%40%50%60%70%80%90%

100%

1-mei-04

31-mei-04

30-jun-0430-jul-0429-aug-0428-sep-0428-okt-0427-nov-0427-dec-0426-jan-0525-feb-0527-m

rt-0526-apr-0526-m

ei-0525-jun-05

Frac

tion

of g

ranu

les

as %

of T

DS

GSBR1 TotaalGSBR1 >0.6GSBR1 0.6-0.425GSBR1 0.425-0.212

Process Conditions Ede STP

- Untreated raw wastewater

- Stable granulation with 70 – 90% granules

- Concentration 10-12 kg/m3 MLSS

- Loading 0.05 – 0.06 kg BOD/(kgDS.d)

- Specific loading 0.81 – 1.05 kg COD/(m3.d)

- Sludge characteristics

• SVI30 = 50 - 60 ml/g (130 for conventional)

• SVI5 / SVI30 = 1.1

Performance Ede STP

- Stable granulation

- Effluent quality

• without post treatment:

o Portho < 1 mg/l (no chemicals)

o (NH4 + NO3)-N < 10 mg/l (13 °C)

o SS < 30 mg/l

• with post treatment

o SS < 5 mg/l

- Recent improved operation results in lower SS

NeredaTM process configurationEU-discharge regulations

NeredaNereda

ANAANA PDNPDN ATAT SCSC

Activated SludgeActivated Sludge

NeredaTMNeredaTM

NeredaTM process configurationnew EU-discharge regulations

NeredaNereda FF

ANAANA PDNPDN ATAT SCSC

Activated SludgeActivated Sludge

NeredaTMNeredaTM

FF

Current technology status

- Industrial units in operation since 2005

- Two municipal units under construction (start-up:

May 2008 and July 2008)

- Approx. 6 others in various preparatory state

(pilot validation detailed design tender)

- National Nereda Research Alliance

Epe STP

Epe STP

Epe STP

Summary

Nereda is a breakthrough.....- Simple- Compact- Sustainable- Low investments- Low operating costs- Simultaneous biological organic,

N and P- removal- Good or Excellent effluent quality

.....and shows serious action:- First industrial applications are running- Many others and municipals will follow soon

Ingenuity award 2005

Process Innovationaward 2006

Water Quality & Safety

award 2007

DOW energyaward 2007

Simon StevinGezel Award 2007

More information?

www.nereda.net

www.DHV.com

More information?

www.nereda.net

www.DHV.com

Comparison

BNR Activated Sludge

BNR NeredaTMparameter

effluent quality good similar or better

process stability good similar or better

footprint 100% 25%

energy consumption 100% < 65-75%

sludge production 100% similar or lower

MLSS in reactor 3-5 kg/m3 10-15 kg/m3

CAPEX 100% significantly lower

OPEX 100% significantly lower

SVI and DS

0

3

6

9

12

15

01-01-05

29-01-05

26-02-05

26-03-05

23-04-05

21-05-05

18-06-05

16-07-05

13-08-05To

tal D

S-co

ncen

tratio

n (k

g/m

3)

0

40

80

120

160

200

SVI (

ml/g

)

DS-concentratie SVI 5 SVI30 10 per. Mov. Avg. (DS-concentratie)

N-removal

05

10152025303540

01-12-0431-12-0430-01-0501-03-0531-03-0530-04-0530-05-0529-06-0529-07-05

NH

4-N

+ N

O3-

N (m

g/l)

Reactor 1 Reactor 2

Pre-settled

Pre-settled Raw w astew ater