Green STP Technology Portfolio
Every Sarvo Green STP treats sewage biologically — no chlorine dosing, no coagulants, no polymer. What changes between technologies is footprint, energy, effluent grade and how much operator attention the plant needs. Pick by constraint, not by fashion.
India's most specified decentralized STP technology. The Sequencing Batch Reactor performs every treatment step — fill, aerate, settle, decant — inside a single PLC-controlled reac…
MBBR is a continuous-flow biological process where the biomass lives as a protected biofilm on free-moving plastic carriers instead of floating in the mixed liquor. No sludge recir…
MBR combines activated sludge biology with 0.04–0.4 micron membrane filtration, replacing the secondary clarifier with an absolute physical barrier. The result is effluent of excep…
Japan runs over 7 million Johkasou units under the Johkasou Law of 1983. Sarvo's decentralized range brings that philosophy to India: a fully factory-manufactured FRP vessel that i…
Constructed wetlands use engineered gravel beds, wetland vegetation and root-zone microbiology to treat sewage with almost no electricity and almost no mechanical equipment. Where …
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Run the calculatorHead to head
Process, performance, footprint, economics and operations — the same parameters consultants use in a technology selection note.
| Parameter | SBR | MBBR | MBR | Decentralized | Constructed Wetland |
|---|---|---|---|---|---|
| Treatment Principle | Suspended growth, batch | Attached growth, continuous | Suspended growth + membrane | Combined anaerobic/aerobic | Natural bio-physical-chemical |
| Hydraulic Regime | Batch fill-and-draw | Continuous flow | Continuous flow | Continuous/semi-batch | Continuous gravity flow |
| Typical HRT (hours) | 7–12 | 4–6 | 6–10 | 8–24 | 24–72 |
| MLSS (mg/L) | 2,500–4,000 | N/A (biofilm) | 8,000–15,000 | N/A (biofilm) | N/A |
| Clarifier Required | No (batch settling) | Yes (secondary) | No (membrane) | No (integrated) | No |
| Parameter | SBR | MBBR | MBR | Decentralized | Constructed Wetland |
|---|---|---|---|---|---|
| Typical BOD Outlet (mg/L) | <10 | 10–20 | <5 | <10 | 15–30 |
| Typical COD Outlet (mg/L) | <50 | 50–100 | <20 | <50 | 50–100 |
| Typical TSS Outlet (mg/L) | <10 | 10–30 | <2 | <20 | 15–30 |
| Total Nitrogen Removal | Good (anoxic cycling) | Requires anoxic zone | Moderate-Good | Moderate | Good (hybrid systems) |
| Pathogen Reduction | Moderate (needs disinfection) | Moderate (needs disinfection) | High (membrane barrier) | Moderate | High (VF systems) |
| Footprint (m²/KLD) | 1.5–3.0 | 1.0–2.5 | 0.5–1.5 | 1.0–2.0 | 5.0–15.0 |
| Reuse Suitability | Good (with tertiary) | Moderate (with tertiary) | Excellent (direct) | Good (with tertiary) | Limited |
| Parameter | SBR | MBBR | MBR | Decentralized | Constructed Wetland |
|---|---|---|---|---|---|
| CAPEX (relative) | Medium | Low-Medium | High | Medium | Low-Medium |
| OPEX (relative) | Low-Medium | Low | High | Low | Very Low |
| Electricity (kWh/KL) | 0.5–1.0 | 0.4–0.8 | 0.8–2.5 | 0.3–0.6 | 0–0.1 |
| Operator Requirement | Semi-skilled (PLC-assisted) | Semi-skilled | Skilled (membrane mgmt) | Minimal | Minimal (periodic) |
| Automation Level | High (PLC essential) | Low-Medium | High | Low-Medium | Minimal |
| Sludge Generation | Low-Medium | Low | Low (high MLSS) | Low | Very Low |
| Expected System Life | 20–25 years | 20–25 years | 20 yrs civil + membrane | 30–50 years (FRP) | 25+ years |
| Shock Load Tolerance | Moderate (batch buffer) | Good (biofilm resilience) | Low (membrane sensitivity) | Moderate | Low |
| Power Failure Impact | Significant | Significant | Critical | Moderate | None |
| Noise | Blower noise (manageable) | Blower noise | Higher (air scour) | Low (<50 dB) | None |
Beyond the reactor
Most failed STPs in India did not fail biologically — they failed because grease, grit, sludge or odour was never engineered for. Sarvo supplies the whole train.
Stop fats, oil and grease before they reach the biology
Kitchen and canteen wastewater carries 100–400 mg/L of fats, oil and grease. Left untreated, FOG coats diffusers, blinds MBR membranes, floats sludge in the settle phase and drives odour. A baffled grease trap plus a belt or disc oil skimmer removes the floating fraction continuously and returns it to a collection drum, protecting every downstream stage.
When you need it
The cheapest insurance a plant room can buy
Rags, sanitary waste, hair and grit are the leading cause of pump failures and diffuser fouling in Indian STPs. Sarvo supplies a manual bar screen (6 mm) as standard, with automatic mechanical and fine screens for larger or membrane-based plants, plus a grit chamber where sand ingress is likely.
When you need it
Turn a spiky sewage curve into a steady feed
Domestic sewage arrives in morning and evening surges of 2–3× the average flow. A 12-hour equalization tank with a submersible mixer or coarse-bubble grid flattens both hydraulic and organic load, letting the biological stage be sized on average rather than peak flow — smaller tanks, smaller blowers, better effluent stability.
When you need it
Polish to reuse grade — clarity, colour and odour
A pressure sand filter followed by an activated carbon filter takes secondary effluent from 'compliant' to 'reusable': residual TSS is captured, colour and trace odour are adsorbed, and the water becomes acceptable for flushing lines and vehicle washing without staining or smell complaints.
When you need it
Fecal coliform below 100 MPN/100 mL, guaranteed
UV-C disinfection at 254 nm and over 40 mJ/cm² is the Sarvo standard — instantaneous, chemical-free and with no disinfection by-products. Tablet or dosed hypochlorite is offered where a residual is needed in a long reuse storage line, particularly for firefighting reserves.
When you need it
From 1% solids to a cake you can cart away
Waste activated sludge leaves the reactor at roughly 0.8–1.2% solids. A sludge holding tank with decant return reduces volume, and a screw press or filter press raises the cake to 18–22% solids — cutting disposal tanker trips by an order of magnitude.
When you need it
No smell means no complaints, and no complaints means no shutdown
Odour is the single most common reason residents demand an STP be shut down. Sarvo designs against it: fully submerged aeration, no anaerobic dead zones, sealed covers on the EQ and sludge tanks, forced ventilation at 6–12 air changes per hour, and an activated carbon or bio-filter on the extract where the plant sits below a habitable floor.
When you need it
Treated water only saves money once it is plumbed back
The ROI of a Green STP is realised in the flushing and irrigation network, not in the reactor. Sarvo supplies the treated water tank, hydro-pneumatic pumping, dual-plumbing interface, distinct purple-line identification and flow metering so the water actually displaces tanker purchases — and so the saving is measurable.
When you need it
Tell us the constraint — space, budget, effluent grade or operator availability — and we'll tell you which, and why.