Effluent Treatment Plant Design
Process design and detailed engineering for CPCB-compliant effluent treatment plants across India — from effluent characterisation and technology selection through P&IDs, equipment sizing, civil drawings, and SPCB submission
Overview
About Effluent Treatment Plant Design
Spans Envirotech has been designing effluent treatment plants in India since 1993. Our engineering team has designed ETPs for food processing, FMCG, dairy, pharmaceutical, textile, and general manufacturing industries — covering flows from 5 m³/day compact systems to 5,000+ m³/day large industrial ETPs. ETP design is our core competence: we treat it as a process engineering discipline, not a civil construction project, ensuring that treatment performance is engineered in from day one.
A well-designed ETP is the difference between a facility that consistently achieves CPCB/SPCB discharge standards and one that perpetually struggles with compliance. The most common root cause of underperforming ETPs is inadequate characterisation of the raw effluent — systems designed from assumed or industry-average values rather than actual measured data from the client's specific process. Spans' design process begins with site-specific effluent sampling and laboratory analysis to accurately characterise BOD, COD, TSS, FOG, nitrogen species, pH variation, and any inhibitory compounds before a single line is drawn.
Technology selection is the second critical design decision. The choice between MBBR, activated sludge, MBR, SBR, or a combination depends on: effluent biodegradability (BOD/COD ratio), available footprint, operator skill availability, power reliability, ZLD requirement, and water reuse objectives. Spans evaluates all relevant technologies against the client's specific effluent and operational constraints — not a standard template — to select the process train that delivers compliant performance at the best lifecycle cost.
Our engineering deliverables cover the complete design package: Process Flow Diagrams (PFD) with mass balances, Piping & Instrumentation Diagrams (P&IDs), hydraulic profiles, equipment sizing calculations and datasheets, civil structural drawings for all ETP structures, electrical single-line diagrams, instrument lists, control philosophy narratives, and complete SPCB consent submission packages. Standalone ETP design consultancy is also offered for clients who wish to engage their own contractor for construction.
Specifications
Technical Specifications
| Design Flow Range | 5 m³/day to 5,000+ m³/day |
| BOD Removal | >95% (inlet 500–8,000 mg/L → outlet <30 mg/L) |
| COD Removal | >90% typical |
| TSS Removal | >95% (outlet <100 mg/L) |
| NH3-N Removal | >95% with nitrification (outlet <50 mg/L) |
| Technologies | MBBR, Activated Sludge, MBR, SBR, DAF, ZLD |
| Industry Experience | Food & Beverage, FMCG, Dairy, Pharma, Textile, Manufacturing |
| Design Life | 20 years (civil), 10–15 years (mechanical/electrical) |
| Engineering Standards | CPCB/SPCB, IS codes, BIS standards, IEI guidelines |
| Deliverables | PFD, P&ID, Civil Drawings, Datasheets, SPCB Submission |
Process
ETP Design Process
Effluent Characterisation
Representative sampling of raw effluent across production cycles — including peak load, average load, and CIP/wash cycles. Laboratory analysis of BOD (3-day at 27°C), COD, TSS, pH, oil & grease, ammonical nitrogen, TKN, total phosphorus, heavy metals (if applicable), and temperature. Flow metering to establish daily and weekly variation patterns.
Regulatory Analysis & Design Targets
Review of applicable CPCB/SPCB discharge standards, existing consent conditions, and sector-specific notifications (ZLD mandates, priority sector standards). Design target effluent quality is set at 20–30% safety margin below consent limits to ensure consistent compliance. Special parameters (NH3-N, heavy metals) are explicitly addressed.
Technology Selection & Process Design
Evaluation of candidate unit processes for each treatment stage: primary (screening, equalisation, physio-chemical treatment, DAF), secondary biological (MBBR, activated sludge, MBR, SBR, anaerobic), tertiary (sand filtration, ACF, RO, UV). Process sizing calculations for each unit — HRT, SRT, oxygen demand, chemical consumption, sludge generation.
Detailed Engineering
Complete engineering deliverable package: PFD with mass balance, P&IDs, hydraulic profile, equipment sizing and datasheets, civil structural drawings for all ETP structures (RCC tanks, clarifiers, sludge holding tanks), electrical SLD, instrument list, and control narrative. All drawings developed to design stage and construction issue levels.
SPCB Consent Submission
Preparation of complete State Pollution Control Board consent application — process description, ETP design parameters, P&IDs, equipment list, water balance, sludge management plan, and environmental impact assessment where required. Spans has experience with SPCB submissions across Maharashtra, Gujarat, UP, Rajasthan, Haryana, Karnataka, Tamil Nadu, Telangana, and West Bengal.
Commissioning & Performance Testing
For turnkey ETP projects, the design team provides commissioning supervision and performance testing against design guarantee parameters. Biological system seeding, start-up support, and operator training are included. NABL-accredited laboratory testing documents SPCB-compliant performance.
Benefits
Key Advantages
- 30+ years of ETP design experience across India's most demanding industrial sectors
- Process engineering-first approach — performance is designed in, not hoped for
- Site-specific effluent characterisation — no generic design assumptions
- Technology-agnostic selection — best process for each client's constraints
- Complete SPCB consent submission package included in design scope
- Detailed engineering to construction-ready standard for procurement and tendering
- Proven MBBR, MBR, DAF, and ZLD design capability
- Reference installations at Britannia, Hindustan Unilever, Lotte India, KRBL, and others
- Standalone design consultancy available for clients engaging their own contractor
- Post-commissioning performance guarantee backed by 30 years of operational experience
Applications
Industries & Use Cases
Get a Quote or Technical Consultation
Our engineers can help you select the right effluent treatment plant design configuration for your application.