03 En Actiflo Softening

Technical & Engineering Seminar – 14-15 October 2009

Actiflo™ Softening for industrial water & drinking water applications

Isabelle Lemaître - Philippe Sauvignet

Technical Department


Actiflo® Softening - Agenda

Principles Technology description Actiflo® Softening Strengths Industrial and Municipal potential applications History of development program Design Tools On going and further development program Results of Actiflo® Softening EdF Cattenom Nuclear

Power plant


Actiflo® Softening : Process Principle

Chemical precipitation of : hardness, alkalinity, silica and other constituents (e.g., heavy metals)

from water and wastewater by the addition of : lime / soda, carbonate ion, metallic salts and polymer,

in an Actiflo® including a reaction tank.


Actiflo® Softening : Process PrincipleMain chemical reactions involved

Lime (& soda ash) softening CO2 neutralisation and precipitation

Precipitation of temporary and permanent Ca Hardness Precipitation of temporary and permanent Mg Hardness

Coagulation with FeCl3


Actiflo® Softening – Technologycombines within a single treatment line

a Dynamic Mixing stage for chemicals injection an Enhanced Precipitation reactor with TURBOMIX™ an Accelerated Flocculation stage with TURBOMIX ™ a Lamella settling unit a Sludge recirculation system that allows the re-injection of sludge

Coagulation MaturationContact CAP

Filtration

Raw water

Coagulation Maturation(Floculation)

Clarification 60 m/h

Softening reactor

Carbonates & Sand recirculation

Hydrocyclone

Scraper

Carbonates return Towards sludge treatment

FeCl3

Lime

Microsand


Main advantage: Compactness

Actiflo® Softening challenges competitors: Densadeg softener 20 – 30 m/h

Conventional precipitation softening : 2-6m/h

Multiflo™ Softener: 20-30m/h

Actiflo® Softener : 60-80m/h

Actiflo® Softening - Strengths


Actiflo® Softening Industrial and municipal potential applications

Membrane pretreatment for reduction of potential scaling

Plant Water and Cooling Tower Make-up Water Production

Cooling Tower Sidestream recycling and blow-down reuse

Oil & Gas Produced Water Recycling

SAGD water treatment for reuse

Phosphorus removal

Flue Gas Desulfurization Wastewater Treatment

Acid Mine Drainage Treatment

Wastewater Reuse ( Steel & metals industry, secondary WW…)

Drinking water production


Dec. 2004: Patent about TURBOMIX reactor

July 2005: Patent about ACTIFLO Softening

2005-2006: VWS first references with MultifloTM softening Iscor Newcastle (river water) and Sasol Landlord (cooling water reuse) Clarification velocity < 10 m/h, conventional reaction tank (no

TURBOMIX)

2006: Request from VWS Bus’ to Tech. Dept. of an industrial development program

Actiflo® SofteningHistory of development program


Actiflo® SofteningHistory of development program

2007 – 2009: Development Program: Lab Tests about Actiflo and Multiflo softening D&B of 2 mobile Multiflo/Actiflo Softening pilot plants Pilot Studies: Coca Cola, Acapulco 1st Actiflo® Softening industrial scale

reference in May 09 Well water

Flow-rate: 110 m3/h – Reaction tank RT: 30 min. – upflow velocity: 37 m/h

Solids recycle ratio 10-20:1

Alkalinity: 190 54 ppm as CaCO3 – Turbidity 2 NTU

Coffeyville, Ks – CVR Energy refinery – February 2009 EDF Cattenom Nuclear Power Plant


Actiflo® Softening – Design Tools

Actiflo® Softening mass balance calculation

Optimised performances with :• Continuous recirculation Carbonates• Ajustable return/extraction rate


Actiflo® Softening – Design Tools

PEARL process design Actiflo® Softening module – Under development Precipitation calculations:

Based on thermodynamic equilibrium (solubility) with stoechiometric dosages

Take Activity coefficients into account to correct the solubility constants

Simultaneously solve the different precipitation reactions

Alkalinity include OH- + HCO3- + CO32- + NH3 + HPO42- + PO43- + B(OH)4- + S2- + HS- + SO32- (+ theoretically SiO(OH)3-)

Partially implement “Ion pairing effect”: ions not 100% dissolved as free ions – tied up as soluble aqueous species


Actiflo® Softening – Design ToolsCurrent limits of PEARL Actiflo® Softening module

Softening / precipitation calculations: Assessing the potential for precipitation just on solubility curve is too

optimistic, Oversaturation required Kinetics not taken into account Process is never 100% efficient

Enter a “process efficiency” according to experience (from pilot trials)

Dosage used for precipitation = total dosage x process efficiency

Remaining dosage used to raise pH


Actiflo® Softening – Design ToolsCurrent limits of PEARL Actiflo® Softening module

No relationship between upflow velocity and outlet TSS

pilot trials, operation feedback Makes not prediction of metal hydroxide precipitation

High rate softening Process Note, including Actiflo® Softening and Multiflo ® softening - Under development First revision to be issued end of 2009


Actiflo® SofteningOn going and further development program

EDF pilot trials on Moselle river water and on cooling water

Multiflo® Softening and Actiflo® Softening in parallel on the same river water quality, in cold temperature conditions

Complementary laboratory tests

Ultimate target: Modeling chemical softening processes in order to be able to preliminary design Actiflo® Softening (and Multiflo® Softening) units without prior Jar-Tests or pilot trials, for all kind of water.


Actiflo® Softening pilot TrialsEdF Cattenom Nuclear Power plant


Pilot Plant location & purpose

EdF (Cattenom Site) : Nuclear Power plant (4 x 1300 MW) Purpose : Feedwater to cooling tower treatment Source : River Moselle

Turbidity : 5 to 100 Ntu (typically 15 Ntu) Organic Matter : 3.5 to 5 mg/l DOC (SUVA < 3) Alkalinity / TAC :15 to 17°F (150 – 170 mg/l as CaCO3)


Power Plant General Process flow diagram

Cooling tower

Nuclear Reacto

r

Industrial water production

Boiler feed water

production

Condensate polishing

To WWTP

To WWTP

To WWTP

Actiflo® Softening on :Surface water = River Moselle

Actiflo® Softening on :Cooling water circuit = 1.6 x river Moselle

Purge return to river


Actiflo® Softening operational setting

Lime softening (Solution @ 100g/l); Dose : 120 – 130 ppm Calculation based on 8 x ΔAlk = 8 x 15°F = 120 ppm Target Alkalinity < 30 mg/l as CaCO3

Coagulation (FeCl3 41%) : 20 – 30 ppm

Polymer A-PAM (AN934 SNF) : 0.4 ppm

µsand (drinking water – GA39) Effective size : 80 µm UC = 1.4

µsand concentration = 5 kg/m3

Feedflow : 65 m3/h (60 m/h rise rate)

Recirculation rate (cyclone overflow) : 8.5 m3/h

Contact time softening : 10 mn (flow 65 + 8.5 = 73.5 m3/h)

Sludge discharge flow : 0.3 – 0.5 m3/h ( < 0.8% water loss)


Softening Turbomix reactor Contact time : 10 min @ 60 m/h TSS concentration : 3.5 to 4.5 g/l Solids ratio recirculated / formed : 20/1

Lime addition into a specific tank (mixed with sludge) Sludge extraction by overflow discharge

Actiflo® Softening operational setting


Initial results (Clarified water & sludge)

Clarified water quality at 60 m/h:- TSS < 5 mg/l (Turbidity < 1 Ntu) Alkalinity (CAE) < 30 ppm pH 8.5 ΔTHT : 100 - 120 mg/l as CaCO3 40% DOC removal!

MA cyclone underflow

MA cyclone overflow

Carbonate sludge: Concentration : 30 to 60 g/l No build-up of carbonate around

µsand Good separation sand/sludge


Current and future test work

On river Moselle Run without coagulant (only with a small acid dose) Compare coagulant dosing point upstream & downstream

softening tank Reduce solids ratio (purge more = lower sludge concentration)

On cooling tower water (1.6 x river Moselle) Run at 80 m/h Reduce contact time (softening down to 8 mn) Experience higher solids (Turbidity load) up to 30 – 40 Ntu Experience higher Alkalinity Experience higher DOC (Organic Matter) Study legionnella removal


Conclusions

Very promissing early results More pilot trials needed to validate design enveloppe

Excellent rise rate capability (60 m/h may be more)

Interesting organic removal capabilities (to be studied more)

High sludge concentration (30 – 60 g/l) extremely good thickening capability

Wide range of application both industrial and Municipal

Should sell like hot cakes…


Thank You!

Date post:	14-Jun-2015
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