What is wastewater treatment technology using electrochemical method?

Many advanced technologies have been researched and applied as the demand for wastewater treatment becomes increasingly urgent to protect the environment. Among them, the electrochemical method stands out due to its effectiveness in treating complex wastewater, especially those with high concentrations of pollutants or difficult-to-degrade substances. By combining physicochemical and electrochemical reactions, this technology not only removes impurities thoroughly but also minimizes the use of chemicals, helping to reduce secondary pollution.

1. Overview of the Electrochemical Method in Wastewater Treatment

The electrochemical method is a physicochemical wastewater treatment technique that uses electric current applied to soluble or insoluble electrodes to remove pollutants. Depending on the treatment goals, this method can be applied in several forms, with the most notable being:

• Electrochemical oxidation: Suitable for wastewater containing persistent organic compounds; helps shorten treatment time by converting organics into CO₂ and water.
• Electrocoagulation: Uses sacrificial anodes (e.g., aluminum, iron) to form flocs and precipitates that remove pollutants; particularly effective for dye wastewater or wastewater from the paper industry.

What is electrochemical method in wastewater treatment system?

2. Outstanding Advantages of the Electrochemical Method

• No use of hazardous chemicals: The treatment process is driven by electrical current and redox reactions, completely eliminating the need for dangerous chemical additives. This minimizes risks for operators and avoids secondary pollution.
• Little to no sludge generation: Compared to traditional physicochemical methods, electrochemical treatment produces minimal sludge. As a result, sludge handling costs are reduced and storage space is saved.
• Effective treatment of high-strength wastewater: This method can remove hard-to-degrade organic compounds, heavy metals, and toxic inorganic substances that are challenging for other technologies.
• Fast treatment time: Especially with electrochemical oxidation, pollutant removal time is significantly reduced, improving system throughput.
• Maintains natural color and quality of water: After treatment, water is clear, colorless, and suitable for reuse in various applications.

3. How Does the Electrochemical Method Work?

Electrochemical wastewater treatment combines multiple physicochemical mechanisms across three main stages: electrocoagulation, electrochemical oxidation, and electroflotation. Each stage serves a distinct purpose but works in tandem to thoroughly eliminate pollutants.

3.1. Electrocoagulation

This stage uses direct current to dissolve aluminum or iron anodes, forming hydroxide compounds (e.g., Al(OH)₃ or Fe(OH)₃). These act as coagulants to gather suspended solids, oil, and heavy metals into easily settled flocs.

• Uses sacrificial anodes (aluminum, iron) to create coagulants.
• Removes up to 90% of suspended solids and heavy metals.
• Reduces color and odor of wastewater.

3.2. Electrochemical Oxidation

After coagulation, water is transferred to the oxidation tank, where electric current generates powerful oxidizing agents such as hydroxyl radicals (•OH) and active chlorine. These break down toxic organic compounds into CO₂, water, and harmless salts.

• Produces strong oxidants (•OH, Cl₂, O₃).
• Decomposes hard-to-degrade organic compounds.
• Requires high-oxidation, durable anodes for effective treatment.

3.3. Electroflotation

In this stage, electrolysis produces tiny oxygen (at the anode) and hydrogen (at the cathode) bubbles. These fine bubbles adhere to remaining flocs, oil, and impurities, lifting them to the surface for easy removal.

• Uses ultra-fine bubbles to float pollutants to the surface.
• Removes an additional 10–15% of remaining impurities.
• Results in high-clarity treated water, ready for discharge or reuse.
• Electrochemical Methods Are Widely Applied in Wastewater Treatment Systems

Electrochemical methods are widely applied in wastewater treatment systems

The electrochemical method is a modern wastewater treatment solution that offers numerous advantages over traditional technologies. Thanks to its ability to rapidly and effectively remove pollutants, reduce sludge generation, and ensure high water quality, this technology is increasingly being applied across various industries. Implementing electrochemical methods not only helps businesses meet environmental standards but also contributes to ecosystem protection and sustainable development.