B-CRT
The largest scale deployment of the most advanced public toilet in the world.
Blackwater Circular Reinvented Toilet. 8-stage treatment. Zero discharge. ISO30500 compliant. 4.05kWp solar capacity. 72+ hours off-grid autonomy. Gates Foundation technology.
See B-CRT in action.
Watch how our 8-stage treatment process transforms waste into safe water - all within a 40-foot container.
4-minute overview of the complete B-CRT treatment process
The sanitation challenge.
Traditional public sanitation infrastructure faces critical limitations in water-scarce urban environments.
₹85K
Annual operating cost
Traditional systems require continuous water supply, grid electricity, and sewage infrastructure. Maintenance, water bills, and disposal costs average ₹85,000 annually per unit.
100%
Discharge contamination
Untreated or partially treated wastewater discharge violates Coastal Regulation Zone (CRZ) requirements and contaminates groundwater in water-stressed regions.
6 months
Construction timeline
Built infrastructure requires extensive civil work, sewage connections, water supply lines, and electrical installation. Deployment takes 6+ months per location.
Why districts choose B-CRT.
Built on Gates Foundation "Reinvent the Toilet" initiative. ISO30500 compliant. Verified by Georgia Tech Research Institute. Managed by Ixora Group's 15-year operating experience with 270+ LooCafe locations.
98% water reduction
Near-complete water recycling after initial 10,000L charge. Annual savings: 420,000-600,000 liters per unit. 65% energy reduction vs conventional systems.
55% lower operating costs
Solar-powered operation. Zero sewage fees. Sludge extraction only every 9-12 months. Class A Biosolids end product per EPA standards.
Zero discharge
Complete elimination of sewage system dependencies. Meets coastal city CRZ regulations. No groundwater contamination. ISO30500 water quality output.
Built for every environment.
Two container sizes. Multiple deployment configurations. Customized for your specific needs.
20-foot Compact
Space-constrained locations, heritage sites, narrow urban plots. Full treatment capability in half the footprint.
- 3 cubicles
- 150+ users daily
- Ideal for tight spaces
40-foot Standard
High-traffic public areas, schools, parks, transit hubs. Maximum capacity with full amenities.
- 6 cubicles
- 300+ users daily
- Commercial space included
Universal Access
Every cubicle designed for accessibility. Safety grab bars, adequate space, and barrier-free entry.
- ADA-compliant design
- Safety grab bars
- Individual ventilation
System architecture.
Container specifications
- 40-foot ISO shipping container (20-foot variant available)
- 304 stainless steel internal components (1.5mm thickness)
- Road-transportable to any truck-accessible location
- Installation: 72 hours from site preparation to commissioning
- Fully operational within 96 hours of installation
Cubicle layout
- 6 individual toilet cubicles serving 300+ users daily
- Universal design with accessible features
- Individual ventilation per cubicle
- 6.5m² commercial space for point-of-sale partnership
- 16m² advertising panel space across unit surfaces
Solar power system
- 9 solar panels × 450W each = 4.05kWp total capacity
- Maximum daily yield: 16-20kWh
- 6 battery systems = 20kWh lithium iron phosphate storage
- 72+ hours off-grid autonomy (monsoon resilience)
- Daily consumption: 12-15kWh under normal operation
- Automatic grid switchover for critical systems (optional)
IoT control system
- 35+ monitoring points across all systems
- Industrial-grade edge computing with redundant storage
- Multi-redundant 4G/LTE with LoRaWAN backup
- Three-tiered dashboard: Area executives, Operations, Unit operators
- Gemini 2.5 AI integration for automated reporting
- End-to-end encryption with role-based access controls
8-stage treatment process.
Integrated biological, physical, and chemical treatment achieves ISO30500 non-sewered sanitation standards. 95-98% water recovery efficiency. Processing capacity: 2,000-3,000L wastewater daily.
Complete 8-stage process flow: Blackwater to ISO30500 reusable water
Pre-treatment & Screening
Purpose
Remove large solids and inorganic particles from blackwater influent before biological treatment.
Technology
2mm fine screening with automated solids separation. Prevents downstream equipment damage and improves treatment efficiency.
Performance
Removes debris >2mm. Protects pumps and membranes. First line of defense in the treatment chain.
Primary Anaerobic Digestion
Purpose
Break down organic matter in oxygen-free environment. Reduces BOD load and stabilizes waste.
Technology
2,000L bioreactor with controlled anaerobic environment. Enzymatic pre-treatment accelerates decomposition.
Performance
>90% sludge volume reduction vs conventional systems. Sludge extraction required only every 9-12 months.
Secondary Aerobic Treatment
Purpose
Aerobic biological oxidation of remaining organic matter (BOD/COD) and nitrogen removal through nitrification.
Technology
Fine-bubble diffusion system maintains optimal dissolved oxygen levels. High-efficiency biofilm media for microbial attachment.
Performance
90-95% BOD removal efficiency. Stable performance under varying organic loads.
Membrane Ultrafiltration
Purpose
Physical barrier filtration removing suspended solids, bacteria, and turbidity.
Technology
0.04 micron ultrafiltration membrane. Automated backwash cycle prevents fouling and extends membrane life.
Performance
>99.9% removal of suspended solids and bacteria. Turbidity reduced to <1 NTU.
UV-C Advanced Oxidation
Purpose
Pathogen elimination through UV-C radiation inactivation of viruses and bacteria.
Technology
UV-C lamps at 254nm wavelength. Optimal dose for ISO30500 compliance. Chemical-free disinfection.
Performance
>99.99% pathogen inactivation. E. coli reduced to <1,000 CFU/100mL (ISO30500 standard).
Activated Carbon Filtration
Purpose
Remove trace organic contaminants, color, and odor through adsorption.
Technology
Granular Activated Carbon (GAC) filter. High surface area media captures micropollutants and improves aesthetics.
Performance
Removes trace organic contaminants. Crystal-clear water with no residual odor.
Mineralization & pH Stabilization
Purpose
Balance water chemistry for safe reuse and prevent pipe corrosion.
Technology
Automated pH adjustment and mineral dosing system. Targets pH 6.8-7.2 range for optimal reuse compatibility.
Performance
Consistent pH 6.8-7.2 output. Water chemistry optimized for toilet flushing and cleaning applications.
Final Disinfection & Storage
Purpose
Final quality verification and storage for closed-loop recycling within the system.
Technology
10,000L storage tank with real-time quality monitoring. Circulation pumps maintain water freshness. Continuous sensor feedback.
Performance
95-98% water recovery. Zero external water requirement after initial 10,000L charge. Zero liquid discharge.
Water quality performance.
Independent laboratory analysis by NABL-accredited facilities confirms consistent ISO30500 compliance across all parameters. Quarterly testing demonstrates performance margins of 60-80% below regulatory limits.
| Parameter | Input (Blackwater) | Output (Treated) | ISO30500 Limit | Compliance |
|---|---|---|---|---|
| BOD (mg/L) | 350-600 | <10 | ≤50 | ✓ 80% below |
| COD (mg/L) | 800-1200 | <50 | ≤150 | ✓ 67% below |
| TSS (mg/L) | 400-700 | <5 | ≤30 | ✓ 83% below |
| Total Nitrogen (mg/L) | 80-120 | <10 | ≤50 | ✓ 80% below |
| E. coli (CFU/100mL) | 10⁷-10⁸ | <500 | ≤1,000 | ✓ Meets standard |
| Turbidity (NTU) | 200-400 | <2 | ≤5 | ✓ 60% below |
All measurements verified quarterly by NABL-accredited laboratories using standard methods: BOD (APHA 5210B), COD (APHA 5220D), TSS (APHA 2540D), E. coli (APHA 9222D membrane filtration).
B-CRT Unit #1 at Lumbini Park, Hyderabad
Hyderabad's first zero-discharge public toilet. Official launch with government officials and stakeholders.
B-CRT Unit Exterior - Container-based toilet facility at Lumbini Park
Launch Event - Officials and dignitaries inspecting the B-CRT unit
Technical Presentation - ReFlow team demonstrating B-CRT technology
Launch Team - Stakeholders and partners at the inauguration
Stakeholder Engagement - Discussion with government representatives
Launch Ceremony - Official inauguration of B-CRT at Lumbini Park
See B-CRT up close.
Real photos from our manufacturing facility and deployment sites.
20-foot B-CRT - Compact variant for space-constrained locations
40-foot B-CRT - Full-size unit with 6 accessible cubicles
Accessible Cubicle Interior - Universal design with safety grab bars
Cubicle Access - Individual ventilation and entry doors
Treatment Room - Stainless steel tanks and control systems
8-Stage Treatment System - Complete water recycling infrastructure
How B-CRT compares.
B-CRT versus conventional decentralized treatment approaches in India's wastewater market.
| Parameter | B-CRT | Conventional Batch Systems | Nature-Based Systems | Industry Average |
|---|---|---|---|---|
| Treatment Stages | 8 stages | 3-5 stages | Natural process | 4 stages |
| Water Recovery | 98% | 70-80% | Limited | 75% |
| Footprint Required | 15-30 sqm | 50-100 sqm | 100+ sqm | 60+ sqm |
| Off-Grid Capability | Yes (72+ hours) | Grid-dependent | Passive | Limited |
| ISO 30500 Certified | Yes | Typically no | No | Rare |
| Energy (kWh/m³) | 0.8-1.2 | 0.5-1.5 | 0 | 1.0-2.0 |
| Installation Time | 2-4 weeks | 2-4 months | 3-6 months | 3+ months |
Why B-CRT stands apart
B-CRT is one of only 3 known ISO 30500-certified systems globally. Its 8-stage biological treatment process achieves 98% water recovery while maintaining Category A output quality—exceeding requirements by 60-80%. The containerized design enables rapid deployment in water-stressed, off-grid, or coastal areas where traditional infrastructure is impractical.
Technical FAQ.
What is the complete treatment residence time?
Total hydraulic retention time is approximately 12-16 hours from influent to final treated water storage. This includes 2-4 hours primary sedimentation, 8 hours MBBR biological treatment, and additional time for clarification and filtration.
How is sludge managed in a zero-discharge system?
Sludge from primary and secondary clarifiers is collected in a dedicated holding tank and dewatered using mechanical methods (screw press or belt filter). Dewatered sludge (20-30% solids) is removed quarterly by certified waste management vendors for composting or approved disposal.
What happens during monsoon when solar generation is reduced?
The battery system provides 3-day autonomy (72 hours of operation without solar input). Historical weather data from pilot sites shows this exceeds maximum consecutive cloudy days. System also includes optional grid backup connection for extreme scenarios.
Can the system handle peak usage periods like festivals?
The system processes 2,000-3,000L of wastewater daily. The biological treatment maintains stable performance under varying organic loads due to attached biofilm growth. Buffer storage tanks accommodate short-term surge capacity.
What is the expected equipment lifespan?
Container structure: 20-25 years. Mechanical equipment (pumps, blowers): 5-7 years. Membrane modules: 3-5 years. UV lamps: 9,000-12,000 hours (1-2 years). Battery systems: 5-7 years. All components designed for field serviceability.
Is the system modular? Can we upgrade treatment capacity?
Core treatment capacity is fixed per container (300+ users daily, processing 2,000-3,000L wastewater). 20-foot variant available for space-constrained areas. Multiple units can be deployed in parallel at high-traffic locations. Each unit operates independently with redundancy benefits.
What certifications and validations does B-CRT have?
ISO30500 non-sewered sanitation compliance. Georgia Tech Research Institute independent performance verification. Gates Foundation technical review and comprehensive evaluation. Field testing in challenging environments (China). Electrical systems: IEC 60364 standards. Container: ISO 668 shipping container standards.
How does B-CRT compare to other decentralized treatment systems?
B-CRT integrates 8 treatment stages in a single containerized unit (competitors: 3-5 stages). 98% water consumption reduction vs conventional. 65% energy reduction. 55% lower operational costs. Ixora Group's 15-year operating experience and 270+ LooCafe deployments provide proven maintenance infrastructure. Learn about the technology evolution on LooCafe's G2RT page.
See the system in operation.
Visual overview of the 8-stage treatment process, containerized system layout, and operational features. Pilot deployment footage from Hyderabad & Navi Mumbai.
Technology Rights & Global Access
ReFlow Toilets builds on decades of Gates Foundation-funded research into reinvented toilet technologies. Our systems integrate innovations developed through the Reinvent the Toilet Challenge, adhering to the foundation's Global Access commitment to ensure affordable sanitation reaches underserved communities worldwide.
Reinvented Toilet Initiative Timeline
Reinvent the Toilet Challenge Launched
Gates Foundation invests $200M+ to spur creation of new toilet technologies for 3.5 billion people lacking safe sanitation. Global Access commitment established.
ISO 30500 Standard Published
International voluntary product standard for non-sewered sanitation systems established, defining safety and performance requirements.
Commercial Licensing Begins
25+ innovations available for licensing. Samsung announces royalty-free patents for developing countries. Georgia Tech files 5 provisional patents for G2RT.
First Commercial License Partners
LIXIL becomes first commercial license partner for Georgia Tech G2RT technologies. Duke's Reclaimer licensed to Indian company for 2024-2025 pilots.
ISO 30500 Revised Standards
Updated ISO 30500 standard published with enhanced performance requirements. India's BIRAC continues funding Indian researchers through "Reinvent the Toilet Challenge: India."
B-CRT Launch (Q4 2026)
ReFlow B-CRT system deployment begins, integrating Gates Foundation-supported innovations with ISO 30500 compliance and Global Access principles.
Technology Licensing Structure
Research Institutions
Universities (Georgia Tech, Duke, etc.) develop core technologies with Gates Foundation funding. Technology transfer offices manage patent portfolios and commercial licensing.
Global Access Commitment
Foundation retains nonexclusive license to ensure funded innovations reach underserved markets. Licensees commit to affordable pricing in developing countries while commercializing in developed markets.
Commercial Partners
Licensed manufacturers (LIXIL, Samsung, Indian partners) produce and deploy systems. Partnerships include technology transfer, quality standards, and market-specific adaptations.
Geographic Deployment
No global exclusive territories. Multiple licensees can operate in same markets. India receives special support through DBT/BIRAC collaboration with $2M joint investment.
ISO 30500 Certification
Voluntary international standard provides legal framework for safety and performance claims. Certified systems can be promoted to government agencies and public users.
Government Procurement
Municipalities and state governments procure ISO 30500-certified systems through standard bidding processes. Operational rights granted to government buyers, IP retained by manufacturers.
Intellectual Property & Licensing FAQ
Legal Note: This information is provided for general educational purposes regarding the Gates Foundation's Reinvent the Toilet Challenge and related intellectual property frameworks. It does not constitute legal advice. For specific licensing inquiries, contact the Bill & Melinda Gates Foundation Water, Sanitation & Hygiene program, Georgia Tech Office of Technology Licensing, or other relevant technology transfer offices. ReFlow Toilets integrates publicly available reinvented toilet innovations consistent with Global Access principles. All product claims regarding ISO 30500 compliance are subject to independent third-party certification.
Sources & Further Reading
Deploy in your district.
Pilot unit operational in Hyderabad. 4 additional units deploying over the next 3 months. Schedule a 45-minute technical consultation with our water treatment engineers.
Includes complete engineering specifications package, district site assessment, and deployment timeline planning.