VWS Wastewater technologies

Sri Lanka, 4 December 2013

Kevin PING

2

Contents

1. Moving Bed Biofilm Reactor

2. Biostry Aerated Filter

3. Membrane Bio-reactors

4. Ecodisk

5. Multiflo /Actiflo high rate settler

6. Discfilter

1

Moving Bed Biofilm Reactor

Moving Bed Biofilm Reactor (MBBR)

The process is based on the biofilm principle, and the core of the process is the biofilm carrier elements made from polyethylene with a density slightly below that of water.

The reactors are filled up to 67% of their volume with these carrier elements.

The biofilm carrier elements are being kept suspended in the water by air from the diffusers in the aerobic reactors, and by means of a mixer in the anoxic reactors.

VSS content of biofilm is 90-95% - showing more active biomass per unit volume.

Thin Biofilm is controlled by continuous sloughing due to constant movement of the biomedia.

Several reactors in series may be used to develop specialized bacteria in each stage.

Process Flow Diagram

Biological Treatment Solid & Liquid Separation

• Organics

• Nitrogen

(Nitrification & Denitrification)

• Suspended Solids

• Excess Sludge

Biofilm carriers

Retaining sieves

Submersible

Key Elements in Anaerobic Bio-reactor

Key Elements in Aerobic Bio-reactor

Biofilm carriers

Air grid system

Retaining sieves

Solid Separation

Dissloved Air Floation (DAF)

Lamella Plate Settler (Multiflo / Actiflo)

Conventional Clarifier

Disfilter

Process Combination

Pure MBBR solution

Hybas combination process

BAS combination process

• Organics

• NH4-N

• TN

• NH4-N

• TN

• Organics

• High rate

BAS Combination

BAS combination process

Advantages Removal 50-70% of BOD 2-3 times higher capacity than conventional activated

sludge Improved activated sludge separability and

dewaterability Improved tolerance to variations and disturbances Simple operation

0 500 1000 1500 2000 2500 3000 3500

Foot print, m²

AS+Sedimentation

MBBR+Sedimentation

MBBR+DAF

MBBR+Actiflo®

Ref: Aquateam report no. 03-031: A cost comparison of different processes for treatment of municipal wastewater.

Foot Print

50%

67%

100 kg/d

134 kg/d

Increase Filling degree by adding more biofilm carriers

Future Expansion

MBBR BAS HYBAS

Easy Upgrading

Rectangular covered concrete reactors

Circular Steel Reactors (Bolted or Welded)

Circular fiber glass reactors

Rectangular/Circular open concrete reactors

Possibility to utilise existing tanks

Existingaeration

Conventional Activated

SludgeMBBR

Expansion Phase

ModifiedExistingaeration

An example: an upgrade work for nitrification

Very compact

Simple operation

Robust - tolerates variations and disturbances

No sludge bulking problems

Tolerates high TSS in - operation without primary treatment

Easy to increase capacity by filling in more media

Easy to create multi-stage systems with specialized micro-organisms

Can easily be installed in existing tanks or basins

Technology Advantages

More than 400 installation worldwide

Design Load

Flow: 28,800 m3/d

BOD: 2,900kg/d

COD: 5,925kg/d

TSS: 2,900kg/d

TN: 755kg/d

TP: 107kg/d

Temperature: 10oC

Case Study : Lillehammer, Norway (MBBR)

Effluent Quality

BOD: <10 mg/L

TN: 70% removal

TP: <0.2 mg/L

Parallel Lines

Post Denitrification with external carbon source

Total Volume 3840 m3

Lillehammer, Norway

Influent (mg/L) Effluent (mg/L) Removal

BOD 81.67 3.33 96%

TN 25.46 5.17 80%

TP 3.67 0.08 98%

Average Values – year 2000

12

Biological Aerated Filter

21

Biological Aerated Filter (BAF)

Fixed film process.

Process capable of removing all biodegradable pollutants (carbon,

ammonia and nitrogen compounds)

2nd Generation BAF process developed by OTV (1992), originally for

N/DN applications.

Upflow filtration with floating media bed retained below nozzle floor

Polystyrene beads (Biostyrene ) providing surface area for biofilm

growth and compact media bed for suspended solids removal.

Backwashing utilises treated water under gravity

Modular design (Concrete : 13m2, 28m2, 42m2, 63m2, 84m2, 113m2

<230m2)

What is Biostyr ?

03/12/2013 Direction or Department name 22

Biostyr Filter

Effluent Chamber

Filter Media

Inlet Channel

Pipe Gallery

Backwash Water Pipe

Inlet Pipe

Air Main Drain Air Grid

Nozzle Floor

Process air

Raw water

Filtered water

Outlet Closed

Inlet Open

Filtration Mode

Nozzle floor

Inlet channel

Effluent chamber

Discharge

point

Backwash water

Treated water

Nozzle floor

Outlet Open

Inlet Closed

Inlet channel

Back Wash Mode

Effluent chamber

To back wash

water holding tank

Upflow type, co-current process air and filtration direction

Media S. G. < 1

No maintenance for air grid (perforated tube)

Backwash by gravity, no pump required

Easy access to nozzles

Treated wastewater on top of filter, odour problem eliminated

Nitrification / denitrification in one cell

Special Features

Applications

Secondary Carbonaceous ( C )

Secondary Nitrification ( NII )

Tertiary Nitrification ( NIII )

Denitrification ( DN )

Nitrification and Denitrification ( NDN )

Carbon removal

Nitrification

Nitrification / denitrification

Primary Settler Biostyr®

Influent Effluent

Waste Sludge

Waste Sludge

Biostyr® - Secondary Treatment

Biostyr® NIIIActivated Sludge

Settler

Biotanks

Biostyr® - Tertiary Treatment

Nitrogen

DN -> External Carbon Source

Effluent

Waste Sludge

Influent

Waste Sludge

Biostyr® - 2nd & Tertiary Treatment

Nitrogen External carbon source

Carbon removal Nitrogen

Biostyr® NDN

Influent

WasteSludge

Biostyr® DN

Effluent

Waste

Sludge

Waste

Sludge

Primary Settler

Filter Cell

Open Top

Steel Tank

Covered

Concrete slab & Nozzles

Air Distribution Laterals

Air Feed Header

Aeration System and Filter Cell

Nozzles

Biostyr® Cell

Air Blowers

Biomas

• Material : Polystyrene • Diameter : 3-6 mm• S. G. < 1

Bio-media

Biostyrene®

3.3, 3.6, 4.0, 4.5 and 5.0mm

BackwashWater Pipe

BackwashControl Valve

AirMainInlet Pipe

Pipe Gallery

35

Case Study: Marseille, France (BAF)

CEPTBAF

Chemical Enhanced Primary Treatment (CEPT) phase 1 (underground):- Year of commissioning: 1987- Capacity: 1 620 000 PE- Treatment flow: 246 000 m3/d

Biological system (BAF) phase 2 (underground):-Year of commissioning: 2007-Capacity: 1 865 000 PE-Treatment flow: 360 000 m3/d

Key Process Overview

13. Technical/Electricalroom

7. Actiflo

12. Control/officeextension

6. Treated water outlet

4. Pumping station

10. Ventilation

5. Biofiltration

14. Tunnel liaison forpedestrian

9. Process air

3. Lamellar settling

2. Pre-settling8. Odor treatmentAquilair

1. Pre-treatment

11. Control/office existing

3

Membrane Bio-reactor

The combination of an activated

sludge process with a UF/MF-

membrane filtration called

Membrane Bio Reactor (BIOSEP®).

Separation of the purified water from

mixed liquor by membrane instead

of conventional processes.

Membrane Bio Reactor (MBR)

Principle

Replace the clarifier by a selective physical barrier to :

Keep all the activated sludge in the tanks

MLSS Bacteria

Allows only soluble component to go through the membrane

No Solids in the effluent (TSS < 1 mg/l)

No bacteria or virus (depending on pore size)

Air

Bacteria

VirusSolids

Membrane

Treated

Water

Activated Sludge Reactors

Process Air Blowers

Membrane/filtration Tanks

Aeration Devices

Return/waste Sludge Pumps

Permeate Pumps

Submermsible Mixers

Major Components

Conventional vs MBR Treatment

Compact system, high MLSS concentration, less space

No final clarification (no risk of sludge loss, performance is

independent of the sludge index)

High COD removal, including slowly biodegradable COD (long

biomass retention time)

Reduced reagent levels in phosphorous elimination

Sludge thickening facilities is not required

Benefits over Conventional Activated Sludge

Performance

Parameters Treated Quality

Chemical Oxygen Demand

(COD)

30 - 70 mg/l

(depending on hard COD)

Biological Oxygen Demand

(BOD5)

≤ 5 mg/l

Suspended Solids (SS) < 1 mg/l

Total Nitrogen (TN) 10 - 15 mg/l

(depending on hard nitrogen)

Total Phosphorus (TP) < 0,5 - 2 mg/l

Total coliform 5 log or ≤ 500 U/100 ml

Immersed membranes are placed either directly into the aeration

tank, or into a filtration/membrane tank with recirculation devices.

Main Configurations of Immersed MBR

Operation Sequences

Filtration phase (treatment phase)

- 10 to 12 minutes

Backwash phase

- 30 to 60 seconds

Degasing phase (under-pressure

filtration)

- 10 to 20 seconds

Filtration Phase

Water is filtered from the

outside to the inside of the

fibers by low-pressure suction

(< 0.5 bar).

During filtration, the sludge is

retained by the membranes,

creating a sludge cake on the

outside of the fibers.

Backwash Phase

Fouling is prevented by pumping

back the permeate (filtered water)

is counter-current flows through

the membranes.

Scour air continuously flows up-

ward and also helps to release

the sludge cake.

Membrane configurations

Immersed Flat Sheet

Immersed Hollow Fibre

Skid mounted Hollow Fibre

Worldwide Installation

14

Ecodisk Process

Use of a natural phenomenon

52

In turning, the mill wheel

alternates immersion and

emersion phases,

… that we use to treat

which causes bacterial film development...

Operating principle

wastewater.

02: air input by exchange

with the wet surface (large

contact area)

Active biological mass =

biological turf

02: oxygenation of the

sludge suspended in the

tank (suspended growth)

About 3 to 5 times thicker

at the edge than at the

centre

Immersion

Bacteria degrade and absorb the

polluting organic matter

Waste water tank half full

EmersionBacteria breathe and

absorb the oxygen

Waste water

carrying

polluting

matter

Speed:

3.5 rpm

Motor

reducing

gear

Grease

bearings

Disk : Ø 2 m

Operating principle

Biological treatment by fixed culture

53

54

Complement treatments:

• Physical-chemical phosphate removal: Iron chloride (P > 2 mg/l)

• Global nitrogen : Anoxic zone (NGl > >20 mg/l)

Performance

Outlet standard dischargesTotal load

(g BOD/m²/d)

Max. load on

the 1st module

(g BOD/m²/d)

Retention time

(h)

Level 1: without nitrification

COD < 120 mg/l

BOD < 25 mg/l

7 -12 < 30 > 0.8h

Level 2: TKN treatment

(70 to 90 %)4-6 < 30 > 1h

# Design varies according to temperature and plant size

Fields of application

55

Small and medium communities

Recreation centers, camping

Hotel resorts, other seasonal destinations

Mountainous areas

Rehabilitation and extension of plants

Every export project with minimized civil works

A lot of

pollution

Disks

totality put

in charged

of a lot of

bacteria

Process advantages

56

Adaptation to organic underloadings

By progressive colonization of the disk surface

Not much

pollution

First disks

put in

charged of

a lot of

bacteria

Other advantages

57

Simple operation mode (No regulation for sludge return, dissolved oxygen control)

Low energy consumption (25 % to 40 % less in comparison with activated sludge)

Less maintenance (no blower, mixer, DO control instru-ment…etc)

Easy installation and expansion (Modularity)

Combination of ECODISKTM

58

Installations

… with more than 1,000 product installations in 35 countries

59

Case study : Breil sur Roya, France

Capacity : 3,000 PE

Treatment process:

ECODISK ™ + lamellar clarifier

Sludge treatment: Centrifuge

Process tanks : Concrete

60

15

Multiflo & Actiflo Settler

OPERATION WITHOUT REAGENT

(low flow variation)

OPERATION WITH:

- Coagulant

- Polymer

- Microsand®

(wide flow variation)

Multiflo® Actiflo®

Large scale variation of the inlet flow

OPERATION WITH:

- Coagulant

- Polymer

(average flow variation)

Lamella Clarification

** Lamellar sludge thickening: Actidyn®

Coagulation: Coagulant + -

Flocculation:

Rapid mixing:

Slow mixing:

Polymer

FAST SETTLING

Coagulation and Flocculation

PURPOSE : Settling of settleable particles and colloids by adding metallic salts and polymer.

COAGULATION & FLOCCULATION PRINCIPLES

Coagulation: destabilisation of particular SS by adding metallic salts and rapid mixing

Flocculation: development of big settleable flocs by polymer adding and slow mixing

Coagulation and Flocculation

Hazen velocity:

cosSn.P.T.S L

...

max

PTS

QVH

mirror

mirrorS

QV max

Mirror velocity:

Hazen and Mirror Velocity

Lamella Plates/Tubes

For wastewater :

• Corrugated plates or honeycomb tubes

• Orthogonal spacing : 70-90 mm

• Slop angle : 60° to the horizontal

• Inclined length ≥ 1 m

For drinking water :

• Corrugated plates or honeycomb tubes

• Orthogonal spacing : 35-50 mm

• Slope angle : 60° to the horizontal

• Inclined length : ≥ 1 m

Honeycomb

Corrugated

Multiflo® : Applications

Drinking water.

Wastewater

· Primary

· Tertiary

Sludge thickening.

Surface water treatment.

Multiflo® Series Range

Multiflo® Series Range

Multiflo® Duo:

Coagulation, flocculation and lamellar clarification of water and wastewater.

Multiflo® Trio:

As above, plus sludge recirculation to improve performances and reduce chemical.

Multiflo® Settler

A flash mixing : coagulant injection

A flocculation stage equiped with Turbomix™: flocculant injection

A clarifying section with lamella plates

A sludge recirculation network

An internal thickening area to obtain 3% DS sludge (1 to 10%)

Multiflo® Trio - Sludge recirculation

Sludge recirculation allows chemical dosing saving, (quantities depending on inlet water characteristics), improves the settling and provides a more thickened sludge.

Sludge recirculation reduces the impact of changing inlet water characteristics. The bigger is the plant capacity, the smaller is the impact.

When the SS concentration in the inlet water is small, sludge recirculation may guarantee the SS removing rate.

Performances

Polymer concentration: 0.3 to 2ppm

FeCl3 or Al2(SO4)3, depending on the conditions and outlet request.

Removal efficiency

- Multiflo®: Raw water turbidity up to 1000 NTU.

Clarified water turbidity < 5 NTU

- Multiflo® Trio: Raw water turbidity up to 1000 NTU.

Clarified water turbidity < 3 NTU

Multiflo® Footprint

Conventional settling

2 m/h

Multiflo®

15 m/h

Multiflo® Trio

30 m/h

Conventional settling

Multiflo®

Multiflo® Trio

Major Components

Lamella Plate and Effluent Launder

Support for Lamella Plate Modules

Supporting beams

Lamella platemodules

Lamella platemodules

Effluent launders

Case Study: Shanghai, China (CEPT)

Type: CEPT

Source: Sewage

Wet wether peak flow: 1,200,000 m3/ d

Number of units : 2 units

Settler dimensions: 16 x 16 m

Bailonggang WWTP, Shanghai

Chemical dosage:

· Alum 44 ppm

· Polymer0.35 ppm

Coagulation duration: 1.77 min(peak)

Floculation duration: 9 min (peak)

Upflow velocity: 35 m/h (peak)

COD BOD SS NH3-N PO4-P

(mg/l) (mg/l) (mg/l) (mg/l) (mg/l)

Inlet water 320 130 170 30 5

Outlet water 180 70 40 30 1

Removal rate % 44 46 76 0 80

Actiflo® Process

Actiflo® is a combination of :

Chemical precipitation

Micro-sand enhanced

flocculation

Lamella sedimentation

Design Principle

COAGULANT

POLYELECTROLYT

MICROSAND FAST MIXING

FLOCULATION

RAW WATER

FAST SETTLING

Micro sand for Actiflo Process

Performance Simulation by Jar-Test

1 2 3 1 2 3 1 2 3 1 2 3

1 - PAC2 - PAC + polymer3 - PAC + polymer + microsand

t = 3 s t = 8 s t = 2 min t = 5 min

ACTIFLO ® : Flow Diagram

SLUDGE

HYDROCYCLONE

POLYMER

RAW

WATER

COAGULANT

COAGULATION

INJECTION

MATURATION

TUBE SETTLER

WITH SCRAPER

CLARIFIED

WATER

BALLASTED FLOCS

TO HYDROCYCLONE

MICRO-SAND

Foot Print Comparison

Conventional settling(2 m/h)

Lamella settling(20-30 m/h)

ACTIFLO(80-120 m/h)

Applications

Municipal

Drinking water (Surface & ground water)

Wastewater (Primary & tertiary)

Stormwater (CSO)

Re-use

Industrial

Process water

Wastewater

Hydrocyclone

Steel or cast iron with inner rubber lining or plastic (polyurethane) lining for small-size hydrocyclones.For potable water applications parts in contact with water -food-grade approval.One hydrocyclone per pump (highly recommended); Using larger size hydrocyclones

rather than small ones :• Reduces number as well as

reduce the complexity of the recirculation circuit,

• Reduces clogging risks at inlet and underflow,

• Reduces feed pressure, abrasion and power consumption

Sludge

Micro-sandand sludge

Micro-sand

Recirculation Line

Delivery of the micro-sand and sludge from the lamella settler to the hydrocyclone;

Centrifugal pump (body and impeller) with rubber lining;

Open or vortex impeller is recommended for primary treatment due to presence of fibrous matters;

Rotation speed in range of 1,000~1,700 rpm;

Controlled flow proportional to inlet (approx. 4-6%);

Variable speed control

Advantages

High treatment efficiency

Efficient use of chemicals

Compact system, less space

required

Short start-up time

Stable process

Installations

Drinking water

· More than 130 installations

· Smallest plant: 30 m3/h (St. Augustin, Canada)

· Biggest plant: 40,000 m3/h (Selangor, Malaysia)

Wastewater

· More than 50 installations

· Smallest plant: 150 m3/h (Røros, Norway)

· Biggest plant: 110,000 m3/h (Acheres, France)

Industry

· More than 40 installations

Acheres, FranceTertiary wastewater & CSO - 110,000 m3/h

Case Study: Paris, France (Tertiary & CS)

Application: Tertiary treatment (TP removal)

Total Capacity: 30 m3/sNumber of Trains: 9Capacity per Train: 3.3 m3/sCommissioning: XXXX

Paris, Acheres I WWTP

P-Effluent Limit: 1.0 mg/l

Dosages: 60 mg/l Ferric Chloride0.5 mg/l Polymer

Typical P-Performance (at start-up):

Influent (mg/l) 1.6 - 4.6 (Avg 2.70) Effluent (mg/l) 0.03 - 2.1 (Avg 0.62)Removal (%) 69 – 90 (77)

Tertiary Mode

Operation Modes

Total ACTIFLO Capacity : 513 MGDNumber of Trains: 5 + 1 stand-byCapacity per Train: 103 MGD

Normal

Operation WWTPActiflo®

Receiv

ing W

ate

r

Storm

Operation

WWTP

Actiflo®

Receiv

ing W

ate

r

CSO Mode

Total Phosphorous Removal

0.0

1.0

2.0

3.0

4.0

5.0

1 2 3 4 5 6 7 8 910

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

Hour of Operation

Ph

osp

ho

ro

us

(mg

/L)

0%

20%

40%

60%

80%

100%

Percen

t

Rem

oval

Influent P-PO4 Effluent P-PO4 % Removal

Performance (June 2002)

TSS Removal

0

50

100

150

200

250

300

350

400

1 2 3 4 5 6 7 8 910

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

Hour of Operation

To

tal

Su

sp

en

ded

So

lid

s (

mg

/L)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Perc

en

t R

em

oval

Influent TSS Effluent TSS % Removal

Dry Weather (Tertiary):

• TSS < 12 mg/l or > 60% removal• Ptot. < 1 mg/l w. 60 mg/l FeCl3, or 60% removal• Ptot. < 2 mg/l w. 45 mg/l FeCl3, or 60% removal

Wet Weather (CSO):

• 80% TSS• 80% BOD (Particulate)• 15 minutes to reach 65% TSS removal

7

Discfilter

95

Applications

Effluent polishing of wastewater

Water reclamation and reuse

Product recovery in industrial applications

Process water filtration

Where a filter with small footprint is required

When a low cost alternative to sand filtration is required

96

Operation Principle

Retractable spray bars

Dirty backwash water outlet flange

Backwash level probe

Access platform level

97

Key Features

Discfilter® consists of:A central drumAssembled discs (with

filter cloth)A central axle in which

the filter is suspended Backwash pump StrainerChain, drive &

gearbox

Duplex drive chain

Backwash pump & strainer

Discs

98

Installation

Weir Plate

Outlet Channel

Discfilter

Weir Plate

Concrete Channel

Inlet Channel

99

Automatic Backwash

Level sensor activated

Filter not off line for backwash

All discs cleaned with each rotation during backwash

Basin not drained during backwash

No clean water tank required

Treated filtered water for backwash

< 3% Required for backwash

100

Moving Spray Bar

Discfilter® - Moving Spray BarPrevents streaking of media

More efficient than stationary nozzles

Spray header retracts from basin

• Nozzles replaceable from walkway

• Nozzles not submerge

• Not susceptible to fouling

101

Advantages

Sturdy (commonly made of 304 or 316 stainless steel)

70-80% smaller footprint than sand filters

• Example: 3.0 MGD – 12’ x 8’

• Low install cost

Simple design

• Reliable,

• Minimisation of mechanical and ancillary parts

Simple installation, simple controls

Simple maintenance, simple operation

Flexibility:

• For corrosive environments, components can be made of titanium or special alloys

• Filtration levels and increased capacity can be achieved by simple replacing or adding discs

Area for

sand filter

Area for

Discfilter®

102

General Specification

Capacity: 10,000 to 4,000,000 l/h

Wide range of models: diamaters1.7, 2.1, 2.2 and 3.1 m with up to 20 discs per filter

Filter opening 10-100 microns

Large filter area: up to 112 m2

filter area

Low operating headloss: 8-10”across filter

Strong 10-year operating experience

103

Performance

TSS reduction: 50 - 99% removal

Influent TSS range: 5 – 260 mg/l

Effluent TSS range: 2 – 30 mg/l

(typically < 5 mg/l)

Turbidity reduction: 50 – 95% removal

Influent NTU range: 0.5 – 34 NTU

Effluent NTU range: typically < 2 NTU

104

Case Study: Barcelona, Spain (Tertiary Treatment)

One of the biggest municipal wastewater reuse plants in Europe

Part of the tertiary treatment in Baix Llobregat WWTP (124,000 m3/day)

Process: combination of Actiflo® (3 sets) and Discfilter® (10 sets). Footprint reduction > 80%

Reuse of 50 Hm3/year, currently being sent to the sea

Treated water use: Irrigation, humid area maintenance, flow maintenance of the Llobregat river

Commissioning expected in March, 2006

105

Overview of Site

Tertiary treatment

Thanks for Your Attention!

Process Flow

1