Electrocoagulation Reactor with Rotatable Cathode for Wastewater Treatment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrocoagulation-based wastewater treatment systems are not capable of sufficient remediation of contaminated waters for large-scale commercialization due to high costs and limited treatment volumes.
Innovation Solution
An electrocoagulation reactor design featuring a rotatable cathode with surface features defining water flow paths and two treatment zones with different voltages applied across gaps between sacrificial and non-sacrificial anodes, combined with a clarifier for solid separation, enhances contaminant removal and treatment efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional electrocoagulation systems are used, then treatment capability is provided, but treatment volume is limited and cost is high
Solution Approach 1:
The electrocoagulation system is divided into multiple treatment zones (first treatment zone with sacrificial anode, second treatment zone with non-sacrificial anode) arranged in series, allowing parallel processing of wastewater streams and increasing overall treatment volume while maintaining manageable complexity in each individual zone
Solution Approach 2:
The system transitions from a single treatment zone to multiple treatment zones arranged spatially in series, adding a dimensional aspect to the treatment process that increases throughput capacity without proportionally increasing the complexity of individual treatment units
2Reliability
If single treatment zone is used, then device simplicity is maintained, but remediation efficacy is insufficient
Solution Approach 1:
The treatment process is segmented into distinct zones with different anode configurations (sacrificial vs. non-sacrificial), where each zone performs a specific remediation function, thereby improving overall efficacy while keeping each zone's design relatively simple and modular
Solution Approach 2:
Different treatment zones are designed with different anode types tailored to specific local requirements: the first zone uses sacrificial anodes for certain contaminant removal, while the second zone uses non-sacrificial anodes for other contaminants, optimizing remediation efficacy for different pollutant types in different locations
3Productivity
If uniform voltage is applied across all zones, then system operation is simplified, but treatment optimization is limited
Solution Approach 1:
Each treatment zone is equipped with independent voltage control, allowing the first zone and second zone to operate at different voltages optimized for their specific contaminant removal requirements, thereby improving overall treatment efficiency while maintaining relatively simple independent control systems for each zone
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 effectively treats contaminated water by applying distinct voltages across multiple treatment zones and utilizing a clarifier for solid separation, achieving significant contaminant removal and meeting commercial-scale treatment requirements at a lower cost.
Implementation Method 1
Electrocoagulation is an electrochemical method of treating water contaminated with various species in an electrocoagulation reactor having a cathode and a sacrificial anode. Supplying current to the electrodes causes the release of metal cations (usually iron or aluminum) from the sacrificial anode
Implementation Method 2
Supplying current to the electrodes causes the release of metal cations (usually iron or aluminum) from the sacrificial anode, and the formation of hydrogen gas at the cathode
Implementation Method 3
Rotating the cathode helps to ensure even consumption of the sacrificial anode and inhibit fouling of the active surface of the cathode
Implementation Method 4
The clarifier has a cylindrical side wall, an upper wall, a conical bottom wall, a first outlet port in the upper wall connected to a first outlet conduit and a second outlet port in the bottom wall connected to a second outlet conduit
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
An apparatus (20) for treating contaminated water has an electrocoagulation reactor (26) and a clarifier (30) to receive the effluent of the reactor. The reactor has a reaction vessel (48) having an inlet (58) and an outlet (62), a sacrificial anode (64), a rotatable cathode (68) and a non-sacrificial anode (66). A first gap (70) between the sacrificial anode and the cathode comprises a first water treatment zone. A second gap (74) between the cathode and the non-sacrificial anode comprises the second water treatment zone. The water flow path is from the inlet to the first treatment zone, then to the second treatment zone and then to the outlet. In the clarifier, the reactor effluent is separated into cleaned water and the contaminated sludge.