Electrochemical wastewater treatment equipment: used for wastewater decolorization

Electrochemical oxidation wastewater treatment equipment | High-efficiency decolorization, simultaneous COD degradation, electrode modules do not scale or clog.

This equipment employs advanced electrochemical oxidation technology, specifically designed for treating highly chromatic and recalcitrant wastewater, such as dyeing and printing wastewater, dye production wastewater, ink wastewater, and chemical wastewater. It eliminates the need for large-scale addition of flocculants or oxidants. Through the action of an electric field, strong oxidizing substances (hydroxyl radicals (·OH), active chlorine, ozone, etc.) are generated at the anode, directly destroying chromophores and organic molecular structures, resulting in rapid decolorization of colored wastewater while significantly reducing COD and removing toxicity. The system consists of a pre-filter, an electrochemical oxidation reactor, a dedicated high-frequency DC power supply, and a circulating water tank. It offers advantages such as thorough decolorization, minimal sludge production, automated operation, and a wide pH range adaptability..

core components

Pre-filter: Bag filter to remove large suspended solids, fibers, and other impurities, protecting the electrochemical electrodes.

Electrochemical electrode module: Employs corrosion-resistant, high-performance electrodes with internal flow guiding and water distribution structures.

High-frequency DC power supply: High-power regulated/constant-current power supply with optional pulse output, overload, short-circuit, and overheat protection; adjustable current/voltage density to adapt to wastewater of different colors and concentrations.

Circulating water tank: Constructed of PE, PP, or stainless steel, equipped with a level controller and circulating pump, supporting batch or continuous flow treatment.

Control cabinet: PLC fully automatic control, touchscreen HMI, linked to inlet water, circulating electrochemical treatment, and discharge; fault alarm and remote communication optional..

Working principle

Colored wastewater, after being filtered to remove large particles, enters the circulating water tank and is then pumped into the electrochemical reactor by a circulating pump. Under the action of a DC electric field:

Direct electro-oxidation: Organic dye molecules directly lose electrons at the anode surface, destroying the chromophores and breaking down the molecular structure, thus achieving decolorization.

Indirect electro-oxidation: The anode electrolyzes chloride ions present in the water or wastewater to generate strong oxidizing substances (·OH, O₃, HClO/ClO⁻, etc.). These active species diffuse into the solution, non-selectively oxidizing dyes and other organic matter, rapidly decolorizing and reducing COD.

The system circulates until the effluent color and COD reach the set values. Afterward, the upper scum/sediment is discharged, and the clarified liquid is discharged or reused.

Main advantages

Rapid and thorough decolorization: Effective against reactive dyes, acid dyes, disperse dyes, and direct dyes, achieving a decolorization rate of 90%-99%. Treatment time can be adjusted as needed.

No chemical additives required: Primarily powered by electricity, requiring no chemical additives and producing no residual solid waste.

Simultaneous COD degradation: While decolorizing, COD removal rates can reach 50%-85%, with some wastewater meeting direct discharge or biological pretreatment standards.

High adaptability: Effective for wastewater with pH 3-13; suitable for treating high-salinity, high-concentration, and highly toxic wastewater. Operates under normal temperature and pressure.

Simple operation: PLC fully automatic control; adjusting current/voltage is sufficient to handle water quality fluctuations, eliminating the need for frequent testing and reagent adjustments.

Long electrode lifespan: Electrode modules are non-consumable, scale-free, and non-clogging; corrosion-resistant and passivation-resistant, with a normal service life of over 2 years.

Low footprint: Skid-mounted modular design allows for flexible layout, suitable for new construction or renovation projects.

Technical parameters

Processing capacity:1 – 50 m³/h

Rated power: 5 – 200 kW (depending on processing capacity and wastewater color/COD)

Voltage: 0 – 20 V (adjustable)

Long electrode life: Electrode modules are non-consumable, non-scaling, non-clogging, corrosion-resistant, and passivation-resistant, with a normal service life of over 2 years.

Hydraulic retention time: Determined based on water quality

Decolorization rate: ≥90% (varies depending on the dye, up to 99%)

COD removal rate: 50% – 85%

Circulating water tank volume: 1 – 30 m³

Main material: PP / FRP / 304 stainless steel

Power supply: Customized as needed

Application areas

Dyeing and printing wastewater (pretreatment or deep decolorization)

Dye and intermediate production wastewater

Textile, leather, and papermaking wastewater decolorization

Ink, coating, and paint production wastewater

Chemical wastewater (containing chromogenic structures such as azo dyes, anthraquinones, and triphenylmethane)

Landfill leachate (decolorization and COD reduction)

We can provide electrode selection, current density, and treatment cycle suggestions based on wastewater pilot test results. Please send water samples or water quality parameters to obtain customized solutions.