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Wastewater treatment by Biofilm technology Compact Waste Water Treatment Unit Pilot Project-Tunisia.

Dr.-Eng. Noama Shareef GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Summary

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Principles of municipal waste water treatment

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Biofilm technology for wastewater treatment

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Concept of a hybrid-plant for high Treatment Efficiency (compact- System) for full treatment

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Overview of the WWTP in Bent Saiden / Tunisia

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Process steps of the WWTP in Bent Saiden

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Conclusions / results

2 Mai 20

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Biofilm technology for Wastewater Treatment Purification is performed by a Biofilm:

Biofilm Systems: Bacteria is attached on support media 3 Mai 20

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Overview of the WWTP in Bent Saiden / Tunisia

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Research project: Hybrid biofilm plant.

The pilot unit is supported by German Ministry of Development and Research.

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200 PE, Inflow 30-40m3/d, BOD 20kg/d GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Process steps of the WWTP in Bent Saiden Primary Sedimentation-Tank De-nitrification Inflow C-Stage Sedimentation Tank Secondary Sedimentation Tank Outlet Nitrification (N1-N3) Sludge Tank GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Concept –system of hybrid-plant The conventional upstream denitrification process

Primary treatment (screen, settling) Denitrification (anoxic conditions) Sludge recycle C/N Elimination (aerobic conditions) Internal recycle Final settling

The compact-system process

Primary treatment (screen, settling) Denitrification (anoxic Moving bed) Internal recycle Intermediate settling C/N Elimination (aerobic fixed bed) Final settling with 6 Best practice: MOFIX

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Concept - system of hybrid-plant

denitrification BOD removal settling Nitrifikation settling recycle Concept - system of hybrid-plant

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Demonstration of Deni- stage in WWTP-Tunis Inflow

Separation Screening sheet

outet to

intermedia sedimentation tank Mixer 836m²/m³ BCN 09

C-Stage DeNi

Recerculation line Air supply + Layout of Denitrification and C-removal stages Spicall Mixer • • For de-nitrification reactor a specific density above 1 kg/l should be applied.

A special shaped mixing device must be tested and applied because agitator of moving bed system with propeller shaped mixers often leads to the damage of carriers.

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Moving bed for De-nitrification -Stage

9 Text über "Einfügen Kopf- u. Fußzeile" einfügen

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Fixed Bed Reactor with BIOdek ® for Nitrification

10 Mai 20

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Nitrification in 3 phases

11 Text über "Einfügen Kopf- u. Fußzeile" einfügen

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Aeration device for Nitrification Stage GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Conclusions / results

Removal rates (%) during 80 day start-up period (without process optimization)

Mo/Fix-Hybrid ® - Data & results pilot plant GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Conclusions / results

Treatment of N in the WWTP Treatment of BOD in the WWTP

14 Text über "Einfügen Kopf- u. Fußzeile" einfügen

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Conclusions / results -

Compact System

Comparison between activated sludge and compact-system design Denitrification Carbon removal Interm. Settling Nitrification Final settling

Total volume Activated sludge Tank (m³) MOFIX Tank (m³)

714 75 127

MOFIX Media (m³)

37,5 80 714 263

1691

143 444 57

846

30 333 11

492 MOFIX Media (Type)

BCN 14 KVP 623 FS41.84

KVP 618 FS41.50

15 Best practice: MOFIX

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Conclusions / results Compact System

• Compact-System (Mofix) is a wastewater treatment process designed for highest standards, reliable and easy to operate.

• The effluent concentrations of MOFIX treated municipal wastewater comply with highest German and European standards for BOD, COD, NH4-N and NO3-N • The treated wastewater by compact system MOfix (BOD5≤10 mg/l, COD ≤100 mg/l, TSS: ≤25 mg/l, NH4-: ≤2 mgN/l, NO3≤10 mgN/l) can be reused for irrigation after disinfection or discharged to the Water bodies • The generated excess sludge can be exposed for drying in sludge drying beds which can be built in the proximity of the unit. And reuse it for Agriculture. 16 Mai 20

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Thank you very much for your attention

17 Mai 20

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Demonstration of Deni- stage in WWTP-Tunis Structure of a moving bed

• (1) mixing device

(slow motion)

• (2) moving bed carrier

(max 50% filling)

• (3) baffle • (4) screen

(30 m/h)

• (5) diffusors 18 Best practice: MOFIX

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

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Overview in 3-D of the WWTP

Final clarification Nitrification in 3 phases (fixed bed) Recirculation Screening Agitator Denitrification reactor Sludge thickener BOD removal fixed bed Intermediate clarifier

GEA Heat Exchangers / GEA 2H Water Technologies GmbH

Aims of waste water treatment Biological waste water treatment

It is a type of waste water treatment in which microorganisms such as bacteria are used to remove pollutants from waste water through biological stag,

Wastewater treatment means:

removal of pollutants like solids, organic matters i.e. BOD-load and inorganic matter (nitrogen, phosphorous, Heavy metals etc.).

• BOD removal • Nitrification • De-nitrification 20

GEA Heat Exchangers / GEA 2H Water Technologies GmbH