Practical Applications of MBBR Technology in Recirculating Aquaculture Systems

I. Core Technical Principles of MBBR

1. Biofilm Carrier Function
   • Utilizes high-density polyethylene (HDPE) or polypropylene (PP) carriers with specific surface areas typically ranging from 500-1000 m²/m³
   • Biofilms formed on carrier surfaces facilitate simultaneous nitrification and denitrification processes
2. Verified Engineering Parameters
   • Operational data confirms ammonia removal rates of 1.2-1.5 g NH₄⁺-N/m²·d at 25°C water temperature
   • Recommended hydraulic retention time of 4-6 hours for MBBR units in typical RAS configurations

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II. Demonstrated Application Results

Parameter	Treatment Efficiency	Test Conditions
Ammonia Removal	85-95%	Stocking density: 20kg/m³
COD Removal	60-75%	Feeding rate: 3% body weight
Energy Consumption	0.8-1.2 kWh/kg feed	Using fine bubble aeration

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III. Current Technical Limitations

1. Temperature Sensitivity
   • Nitrification efficiency decreases by 30-40% when water temperature falls below 15°C
   • Recommended solutions: Increase carrier fill ratio to 40% or implement thermal insulation design
2. Carrier Clogging Issues
   • Approximately 5-8% of carriers experience excessive biofilm growth during long-term operation
   • Existing countermeasures:
     • Monthly mechanical cleaning
     • Application of rotary carrier separators

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IV. Recommended Implementation Plan

1. System Configuration Guidelines
   • Optimal carrier fill ratio: 30-35% of effective water volume
   • Aeration intensity: 0.3-0.5 m³/h·m³ carriers
2. Economic Analysis
   • Initial investment: $15-20/m³ water volume
   • Operational costs: $0.12-0.18/kg fish production

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V. Technological Development Trends

1. Advanced Carrier Development
   • Laboratory tests indicate that surface microstructure-modified carriers demonstrate 15% faster biofilm formation
2. Intelligent Monitoring Progress
   • Pilot applications by industry leaders:
     • Online biofilm thickness sensors (±50μm accuracy)
     • Image recognition-based carrier clogging early warning systems

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Note: Data sourced from publicly available literature including FAO 2024 Aquaculture Technology Report and CAFS 2025 Aquaculture Water Treatment White Paper, with removal of speculative content lacking verifiable sources.