he External Circulation Sludge Bed (ADI-ECSB) is a high-rate anaerobic digestion system that uses granular biomass to treat wastewater. This space-saving process incorporates a patented design developed by HydroThane STP and offered under licence by ADI Systems. This next-generation technology solves many traditional problems with high-rate systems.
The ADI-ECSB is ideal for urban areas and facilities with limited space availability. Wastewater with high concentrations of soluble organics can be easily treated in the compact ECSB system, making this technology an ideal choice for breweries, beverage plants, biofuel processors, or the pulp and paper industry. It can be constructed from various materials such as steel, concrete, or fibre/glass-reinforced plastic (FRP/GRP).
The ADI-ECSB system packs many process benefits into a small footprint:
Cost Savings
• Save on energy costs:
o Low energy consumption design
o Anaerobic treatment significantly less energy-intensive than aerobic systems
o Recover energy from biogas to reduce plant’s fossil fuel usage
• Eliminate wastewater surcharges
Environmental Benefits
• Very compact footprint
• Continuously meet discharge requirements
• Convert organic waste to recoverable green energy (heat and power)
• Improve local and global water security
• Pressurized system design eliminates odor emissions
Process Advantages
• High organic loading rates
• Two stages of biogas-liquid-solids separation:
o Improved process stability
o Superior biomass retention
• Controlled hydraulic and mixing conditions under any situation
• Specially-developed influent distribution system maximizes wastewater contact with granular sludge
Simplified Operation & Maintenance
• No complex internals
• Sealed headspace, eliminating the potential for tank corrosion
• External circulation controls reactor mixing independently from  system operating and loading conditions
• Biogas-liquid-solids separators cope with changes in operating conditions and biogas production
• Data trending for process control