Rajshree Group designs and supplies Secondary Biological Treatment Systems for paper mill effluent. Secondary treatment using activated sludge, extended aeration, or UASB (Upflow Anaerobic Sludge Blanket) reactors removes dissolved organic matter (BOD/COD) from mill wastewater.
Product Overview
Our systems are reliable, energy-efficient, and designed for consistent compliance with pollution control norms.
Key Features
- ✓Surface aerators or fine bubble diffusers
- ✓UASB reactor for anaerobic pre-treatment
- ✓Clarifier with sludge recycle system
- ✓Sludge return pump and control
- ✓DO monitoring and aeration control
- ✓Nutrient dosing (N and P) system
- ✓Secondary sludge thickening system
- ✓Odour control with biofilter
Applications
- Paper and pulp mill wastewater
- Chemical plant secondary treatment
- Food processing effluent
- Textile industry ETP
- Municipal wastewater treatment
Our Turnkey Project Process
We understand your requirements, site conditions, and budget to prepare a detailed feasibility report.
Complete process design, P&IDs, civil layout, electrical single lines, and equipment specifications.
In-house and vendor-sourced equipment manufactured, quality-inspected, and dispatched on schedule.
Our engineers supervise erection, electrical, instrumentation, and commission the plant to design parameters.
Hands-on operator training, performance guarantee trial, and ongoing technical support for the life of the plant.
Get a Free Quote
Tell us your capacity requirement and we'll send a detailed technical and commercial proposal within 48 hours.
Request a Quote →Contact Our Experts
📍 Branch Office: 1913 Gunbarrel Road, Suite 105 Chattanooga, TN 37421, USA |
📍 Branch Office: D7, Varsity Chateau, Uniport Road Aluu, Port Harcourt, Rivers State, Nigeria |
Why Choose Rajshree?
- ✅ 20+ years industry experience
- ✅ 22+ successful projects delivered
- ✅ Serving India, Africa & Middle East
- ✅ Complete turnkey — single point responsibility
- ✅ After-sales support and spare parts
- ✅ Competitive pricing and financing options
Biological Treatment: The Core of Organic Load Removal in Paper Mill ETP
After primary clarification removes suspended solids, the dissolved organic compounds in paper mill effluent — measured as BOD and COD — must be addressed by biological processes. Paper mill secondary effluent typically enters the biological stage with BOD of 500–2,000 mg/L and COD of 1,500–5,000 mg/L, depending on the process. Without effective secondary treatment, this load cannot be discharged to any receiving water body without severe ecological impact.
Rajshree Group designs secondary biological systems using activated sludge (extended aeration), MBBR, or UASB-based anaerobic pre-treatment followed by aerobic polishing — with the technology choice driven by effluent load, land area, energy cost, and target outlet quality. For high-strength effluents (COD above 3,000 mg/L), UASB pre-treatment reduces aeration energy costs by 50–60% while also generating biogas that can be used as boiler fuel.
Rajshree's biological systems are commissioned with seeding and acclimatization protocols — inoculating the aeration tanks with adapted microbial populations from existing paper mill ETPs. This reduces the time to stable biological performance from the typical 3–4 month cold-start period to 4–6 weeks, getting your mill to compliance faster.
For mills with UASB-based secondary treatment, Rajshree designs biogas collection and utilisation systems. A 100 TPD paper mill's UASB reactor typically generates 800–1,500 m³/day of biogas (60–70% methane), which can substitute 15–25% of boiler fuel — providing both environmental and economic benefits simultaneously.
Frequently Asked Questions
Countries We Serve
Rajshree Group supplies and installs our Secondary Effluent Treatment (Aeration) — and complete pulp & paper mill machinery — for mills across India, Africa and the Middle East, with sea-freight delivery, on-site erection, commissioning and after-sales support in every market we serve.