1. 14.03.2005Upgrade of Sana'a WWTP1 Upgrade of the Sana‘a Wastewater Treatment Plant Presentation of the Design Implementation of the New Preliminary Wastewater and Sludge Treatment Facilities

2. 14.03.2005Upgrade of Sana'a WWTP2 Topics  Background  Goals of the Project  Design Criteria  Objectives of the Design  The Final Design  Implementation / Cost

3. 14.03.2005Upgrade of Sana'a WWTP3  1994: Design of the new Sana‘a WWTP by Howard Humphreys, UK, as activated sludge process with simultaneous sludge stabilization  1999: Turn-Key Implementation of the new Sana‘a WWTP (Financing World Bank); Start of operation through Degremont, France (1 year)  2000: Takeover and responsible Operation through Sana’a Water and Sanitation Local Corporation (SWSLC)  Operational Problems right from the very beginning of operation:  Overloading of WWTP due to high BOD 5 -concentration  High operation costs due to high energy consumption  Sludge not stabilized causing odor nuisance  Odorous nuisance along the inlet trunk main sewer  Utilization of treated wastewater and sludge for irrigation / agriculture had not been solved 1 Background

4. 14.03.2005Upgrade of Sana'a WWTP4  Remedying Measure: Execution of a Feasibility Study (August 2000 until May 2001) Decision for Implementation of Sana‘a WWTP Upgrade (10/2002)  Decision for Implementation of Sana‘a WWTP Upgrade (10/2002) Preparation of Final Design + Tender Documents according to FIDIC „Red Book“  Consultant: CONSULAQUA Hamburg GmbH   Preparation of Final Design + Tender Documents according to FIDIC „Red Book“  Consultant: CONSULAQUA Hamburg GmbH 1 Background

5. 14.03.2005Upgrade of Sana'a WWTP5  Implementation of technical measures for upgrade of Sana’a WWTP (design flow Q = 65,000 m³/d in 2020)  Improvement of treatment efficiency + operational stability  Reduction of external energy input  Improvement of the quality of dried sludge to allow proper sludge marketing  Implementation of technical measures to reduce massive odor problems to a tolerable level 2 Goals of the Project

6. 14.03.2005Upgrade of Sana'a WWTP6 3 Design Criteria Effluent Requirements  BOD 5 < 30 mg/l(inflow: BOD 5 = 1,100 mg/l)  SS < 30 mg/l(inflow: SS = 1,200 mg/l)  pathogen removal: -Coliform Germs < 1,000/100 ml -Worm eggs < 1/Liter  Avoidance of infections to those working on irrigated fields and those consuming vegetables grown on fields  Existing wastewater treatment stage will be fully able to fulfil effluent requirements if sludge problem is solved

7. 14.03.2005Upgrade of Sana'a WWTP7 Wastewater Characteristics / Target Years 3 Design Criteria

8. 14.03.2005Upgrade of Sana'a WWTP8 4 Objectives of the Design  High safety of operation (  redundant systems, hydraulic crosswise connections)  O & M-requirements (  easy handling & maintenance of treatment facilities)  Staff requirements (  number and skills of staff  degree and complexity of automation)  Local availability of material, equipment and consumables  Minimization of investment costs  Essential savings in operation costs  Minimization of environmental impacts (odor, noises)  Future extension possibilities (  modular structure of plant layout, extension areas)

9. 14.03.2005Upgrade of Sana'a WWTP9 5 The Final Design  Technical Measures to be implemented under the Sana’a WWTP Upgrade Project  New Inlet Pumping Station with pre-applied Coarse Screens  Fine Screens  Primary Settling Tanks / New Distribution Chamber  Retention Basin  Primary Sludge Thickeners  Anaerobic Digesters (incl. Auxiliary Building)  Stabilized Sludge Thickeners  Co-Generation Plant + Boiler Station  Gasholders with gasflare  Adaptation of Electrical Power Supply and Distribution  Additional 44 Sludge Drying Beds  Odor Control Measures  Gasholders with gasflare  Adaptation of Electrical Power Supply and Distribution  Additional 44 Sludge Drying Beds  Odor Control Measures WWTP Upgrade Sludge Treatment Odor Control

10. 14.03.2005Upgrade of Sana'a WWTP10 The new plant layout in complete overview Arrangement of New Plant Layout (new structures in RED color) + 4 clearly defined operational areas:  IPS/Mechanical Wastewater Treatment  Biological Wastewater Treatment  Sludge Treatment  Gas Utilization  IPS/Mechanical Wastewater Treatment  Biological Wastewater Treatment  Sludge Treatment  Gas Utilization + Connection of new with existing facilities is easy  continuation of operation during construction + Future Extension of Plant is very easy + O & M requirements can be kept at acceptable standards

11. 14.03.2005Upgrade of Sana'a WWTP11 The new layout in detail Mechanical Wastewater Treatment New: Coarse / Fine Screens, Inlet PS, Aerated Grit Chambers, Primary Settling Tanks and Magnetic Flow Meter + Logical and modular arrangement of Screens, Grit Chambers and Primary Settling Tanks allowing easy extension in quantity + Separate Coarse and Fine Screens result in higher efficiency, easier unloading of screenings, and better O & M conditions + New aerated grit chambers provide high grit removal efficiency (protection of new digesters) + The logical spatial arrangement of the mechanical treatment facilities allows for improved hydraulic conditions + Construction of the new mechanical treatment facilities can be carried out in one take without interfering plant operation + Emergency overflow can be further used - The new arrangement requires construction of a new Inlet Pumping Station and extension of the main incoming sewer

12. 14.03.2005Upgrade of Sana'a WWTP12 The new layout in detail Biological Wastewater Treatment Conversion of Simultaneous Sludge Stabilization to Activated Sludge Process (Carbon removal only) + All tanks and connecting pipes can be further used + Existing Inlet Pumping Station can be used as Return Sludge Pumping Station + Mixing of pre-treated wastewater and return sludge and the following distribution on to 8 treatment lines can be facilitated by construction of only one additional structure

13. 14.03.2005Upgrade of Sana'a WWTP13 The new layout in detail Sludge Treatment 3 new Digesters @ 10.000 m 3, Gravity Thickeners for Primary Sludge & Digested Sludge (4 in total), 2 Gas Holders, Co-Generation Plant, Boiler Station + Implementation of third Digester considerably improves operational and process safety + Expensive Polymers will not be needed anymore + Due to new spatial arrangement all sludge thickeners can be fed by gravity + Short distances between digester and thickeners allow for reduced pumping cost + Gas Utilization facilities are very close together + Gas Utilization allows for considerable reduction of specific energy supply from external sources (approx. 65 %)

14. 14.03.2005Upgrade of Sana'a WWTP14 The new Digesters (Profile)

15. 14.03.2005Upgrade of Sana'a WWTP15 The new layout in detail Odor Control 3 Biological Filters close to the new Screen Building, Return Sludge Pump Station, and PS Thickeners + Easy to operate and maintain + Low running cost + High Efficiency

16. 14.03.2005Upgrade of Sana'a WWTP16 5 The Final Design Power Supply Concept  Introduction of 4 gas generator sets, each rated @ 626 kW  Balance of Total Power Requirement for future Sana‘a WWTP  Maximum Power Reduction is 25%  Considering the extended capacity (increase of treatment capacity from 450,000 PE up to 1,000,000 PE,) the specific power consumption of Sana‘a WWTP can be reduced by approx. 67%

17. 14.03.2005Upgrade of Sana'a WWTP17 Implementation (planned)  09/2005: Award of Contract  10/2007: Commencement of Operation under Responsibility of the Contractor + Start of Staff Training (1 Year)  10/2008: Takeover through SWSLC Investment Cost (estimated)  Civil Works:18.2 Mil. USD (incl. Sludge Drying Beds)  Mechanical Works: 5.8 Mil. USD  Electrical Works: 2.6 Mil. USD  Incontingencies: 1.6 Mil. USD  Engineering: 1.8 Mil. USD GRAND TOTAL30.0 Mil. USD 6 Implementation & Cost

18. 14.03.2005Upgrade of Sana'a WWTP18 Thank You