100 KLD Sewage Treatment Plant – MBBR Technology
MBBR is an advanced attached-growth biological process using floating bio-media to increase active surface area and reduce tank size. This page shows a practical 100 KLD MBBR design (20 hr/day) — volumes and equipment are indicative and must be finalized after site visit & jar test.
Process Flow (MBBR) — Sequence
Sludge settled in clarifier: RAS (Return Activated Sludge) pumped back to MBBR, excess sludge → sludge holding & dewatering (filter press / drying beds).
Design Basis & Calculations
Design daily flow (Qd) = 100,000 L/day • Operating hours = 20 hours/day
Design hourly flow (Qh) = 100,000 / 20 = 5,000 L/hr.
Influent BOD (assumed) = 300 mg/L (update after lab data). Target effluent BOD < 30 mg/L (after polishing).
Tank Volumes (Indicative)
| Unit | HRT / Note | Calculated Volume (L) | Rounded (m³) |
|---|---|---|---|
| Collection / Equalization Tank (with disc diffusers) | 6 hours | 5,000 × 6 = 30,000 L | 30 m³ |
| Bar screen & O&G chamber | 0.5–1 hour | ~5,000 L | 5 m³ |
| MBBR Aeration Tank (with PP media) | 6 hours HRT (media carriers) | 5,000 × 6 = 30,000 L | 30 m³ |
| Secondary Clarifier | 2 hours | 5,000 × 2 = 10,000 L | 10 m³ |
| Clarified Water / Buffer Tank (PSF feed) | Buffer | ~2,000 L | 2 m³ |
| Final Treated Water Tank (reuse) | Buffer | ~5,000 L | 5 m³ |
| Sludge holding / Thickener | Intermediate | ~1,000 – 2,000 L | 1–2 m³ |
Total (approx): ~83 m³ (excluding PSF/ACF vessels). Volumes can be optimized using process options and vendor prefabricated modules.
MBBR Media Specification & Filling
| Property | Value / Note |
|---|---|
| Media Type | PP / HDPE Floating Bio-carrier (Virgin material) |
| Surface Area | 500 – 650 m² / m³ (typical, vendor dependent) |
| Filling Ratio | 55 – 65% of aeration tank volume (recommended) |
| Media Density | Low density to stay suspended & free-moving |
| Advantages | Increased biofilm surface area → higher OLR, compact reactor, stable performance |
We will specify exact carrier type, surface area and fill % with vendor during final design—adjust for influent characteristics and specific load.
Air / Blower & Power Estimate
Using conservative transfer & safety margin → design air ≈ 1,300 m³/day ≈ 65 m³/hr. Recommend blower capacity: 70–100 m³/hr (2 blowers for redundancy).
MBBR may require slightly higher air for media mixing & scouring; check vendor recommendation. Typical blower motor power 7.5 – 15 HP depending on type and head losses.
Expected Performance & Reuse
| Parameter | Influent (Design) | Expected Treated (After PSF+ACF+Disinfection) |
|---|---|---|
| pH | 6.5 – 7.5 | 6.5 – 7.5 |
| BOD | ~300 mg/L | < 30 mg/L |
| COD | ~900 mg/L | < 200 mg/L (site dependent) |
| TSS | ~150 mg/L | < 30 mg/L |
| Oil & Grease | ~50 mg/L | < 5 mg/L |
Typical reuse: gardening, toilet flushing, car wash, pavement wash. For critical reuse (RO feed or cooling towers), include UF/RO & conduct lab validation.
Operation & Maintenance
- Maintain DO in aeration: 2.0 – 3.5 mg/L (higher air for media mixing & scouring).
- Monitor MLSS & biofilm health periodically; adjust wasting to control solids.
- Inspect media movement & prevent media carryover to clarifier (screening at clarifier outlet recommended).
- Blower & diffuser maintenance: clean diffusers & check blower oil/drive belts per schedule.
- Periodic sludge dewatering; manage sludge disposal as per TNPCB/CPCB.
Get Quick Quotation / Technical Proposal
Free site visit & jar test for final design & price. Send site photos, sample report (if available) and project brief.
Sales / Technical: +91 97100 35249 • Service: +91 99623 95875 • Email: rrrenviro@gmail.com