1. Project Overview

Located in Côte d’Ivoire, West Africa, this project is a 200 tons per day (200 T/D) domestic sewage treatment plant built to support a local urban community, serving approximately 5,000 residents and solving the problem of direct discharge of domestic sewage in the area. The project strictly complies with the Ivorian *Hygiene and Drainage Act* and WHO discharge standards. Adopting mature integrated domestic sewage treatment equipment and technologies from China, it achieves stable and compliant discharge of treated sewage, helping improve local public health and ecological environment.

Core Parameters

- Treatment Capacity: 200 m³/d (200 tons/day), hourly treatment capacity 8.3 m³/h

- Influent Water Quality: COD 250–350 mg/L, BOD₅ 120–180 mg/L, SS 150–250 mg/L, NH₃-N 25–35 mg/L, pH 6.5–8.5

- Applicable Standards: National Sewage Discharge Standards of Côte d’Ivoire + WHO Guidelines for Domestic Sewage Discharge

  - Effluent: COD ≤ 50 mg/L, BOD₅ ≤ 10 mg/L, SS ≤ 10 mg/L, NH₃-N ≤ 5 mg/L, pH 6–9

2. Process Flow

A mature and stable process is adopted to adapt to the high-temperature climate and operation & maintenance conditions in Africa:

Pretreatment + A²/O-MBBR Biochemical Treatment + Deep Sedimentation + Disinfection

1. Pretreatment: Mechanical grating (5 mm gap) → Equalization tank (HRT = 4 h)

2. Biological Treatment: Anaerobic tank → Anoxic tank → A²/O-MBBR aerobic tank (high-efficiency biological carriers)

3. Advanced Treatment: Inclined tube sedimentation tank → Quartz sand filter

4. Disinfection: Sodium hypochlorite disinfection tank (contact time 30 min)

3. Core Equipment Models

1. Rotary mechanical grating: HG-500, grating gap 5 mm, power 0.75 kW

2. 200 T/D integrated A²/O-MBBR equipment: Model WSZ-200, dimensions 13.5×2.8×2.8 m, carbon steel with anti-corrosion coating

3. Submersible lift pump: 50WQ15-10-1.1, 2 sets (1 duty, 1 standby)

4. MBBR biological carriers: Φ25 mm polyethylene suspended carriers, specific surface area 500 m²/m³

5. Inclined tube sedimentation tank: XC-200, surface loading rate 1.0 m³/m²·h

6. Quartz sand filter: GLQ-200, automatic backwashing

7. Dosing system: Automatic PAC/PAM dosing device

8. Disinfection system: Sodium hypochlorite generator, output 500 g/h

4. Treatment Performance

After stable operation, the domestic sewage treatment effect is excellent, and the effluent quality fully exceeds the standards of Côte d’Ivoire and WHO:

- COD: 35–48 mg/L (removal rate ≥ 86%)

- BOD₅: 6–9 mg/L (removal rate ≥ 93%)

- SS: 5–8 mg/L (removal rate ≥ 96%)

- NH₃-N: 2–4 mg/L (removal rate ≥ 90%)

The system features strong shock load resistance, adapts to fluctuations in water quality and quantity in Africa, is easy to operate and maintain, features low energy consumption, and is suitable for long-term stable operation overseas.

5. Project Advantages & Value

1. Strong technical adaptability: The A²/O-MBBR process delivers high load resistance and adapts to the high-temperature environment of Côte d’Ivoire. The 200-ton integrated domestic sewage treatment equipment is highly integrated, occupies a small area (approx. 38 ㎡) and enables fast installation.

2. Easy operation & maintenance: Fully automatic PLC control with remote monitoring available; no professional operation team required, suitable for local O&M capacity in Africa.

3. Compliance & reliability: Equipment certified with ISO9001 and CE; process data authentic and verifiable, meeting Ivorian environmental supervision and acceptance requirements.

4. Overseas engineering value: Chinese technical standards implemented in West Africa, improving local sanitation, reducing waterborne diseases, and supporting the *Belt and Road* livelihood projects.

The 200 T/D Domestic Sewage Treatment Project in Côte d’Ivoire is a typical application of China’s integrated domestic sewage treatment technology in West Africa. With stable processes, reliable equipment and comprehensive services, it realizes compliant sewage treatment and provides a replicable and promotable solution for urban domestic sewage treatment in Africa, achieving ecological, social and demonstration value for overseas markets.