Flow-Through Aerobic Granular Sludge Reactor With Spatial Zonation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is no known process or mechanism to replicate the sequencing batch reactor (SBR) cycles in a continuous flow through activated sludge basin configuration, which is prevalent in the United States and Canada, limiting the application of aerobic granular sludge (AGS) processes in existing wastewater treatment facilities.
Innovation Solution
A flow through reactor system is designed to replicate the environmental and physical conditions of SBRs by incorporating alternating aerated and unaerated zones, mixing devices, and selector systems to promote and maintain AGS granule formation, allowing continuous wastewater treatment in existing activated sludge basins.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If SBR cycles are used for AGS treatment, then AGS granule formation is achieved, but the system cannot be applied to existing continuous flow activated sludge basins
Solution Approach 1:
The continuous flow reactor is segmented into multiple distinct zones (anaerobic zone, anoxic zone, aerobic zone) along the flow path, allowing each zone to provide specific environmental conditions necessary for AGS granule formation and maintenance without requiring batch operation
Solution Approach 2:
The invention transitions from temporal cycling (SBR batch processes) to spatial zonation (continuous flow with multiple zones), creating the necessary environmental variations along the length of the reactor rather than through time-based cycles
2Ease of operation
If conventional activated sludge floc is used, then the system is simple to operate, but settling and liquid solids separation are inefficient
Solution Approach 1:
The system creates different environmental conditions (oxygen levels, substrate concentrations) in different zones along the flow path, which selectively promotes the formation of granules with specific properties (high density, good settling) while maintaining operational simplicity through continuous flow
3Productivity
If higher biomass inventory is achieved through AGS, then treatment efficiency improves, but reactor volume requirements are reduced
Solution Approach 1:
The system changes key parameters (dissolved oxygen concentration, substrate availability, flow rate) along the reactor length to create conditions that promote high biomass concentration in granule form, achieving higher productivity in a compact volume
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system enables the development and sustenance of AGS granules, enhancing pollutant removal efficiency and reducing reactor volume requirements by maintaining high biomass concentrations, improving settling and liquid/solids separation.
Implementation Method 1
exposure of the granules to feed wastewater in a manner that encourages rapid pollutant adsorption
Implementation Method 2
a first aerated zone downstream of the first unaerated zone, wherein the first aerated zone is under aerobic conditions
Implementation Method 3
The density and sphericity of the AGS allows for improved settling and liquid solids separation compared to conventional activated sludge floc
Data Source
AI summary
A flow through aerobic granular sludge (AGS) system includes a flow through reactor. The flow through reactor includes a first adsorption zone and first and second unaerated and aerated zones and may include a wastewater distribution system and a selector zone. The first adsorption zone includes AGS granules and may include a mixing device. The first and second unaerated zones are under anaerobic, anoxic, or both anaerobic and anoxic conditions and each may include a mixing device. The first and second aerated zones are under aerobic conditions and each may include an aeration device. The flow through reactor is configured such that the wastewater and AGS granules in the first adsorption zone flow continuously from the first adsorption zone through the first unaerated zone, the first aerated zone, the second unaerated zone, the second aerated zone, and optionally to the selector zone and out of the flow through reactor.