UK HQ Your time
Process Technology

Electrocoagulation Systems

Use sacrificial metal anodes to generate coagulants in-situ, eliminating external chemical dosing while breaking emulsions and removing dissolved metals.

What is Electrocoagulation?

Electrocoagulation (EC) uses an electrical current to dissolve sacrificial metal anodes (typically iron or aluminium) directly into wastewater. The dissolved metal ions hydrolyse to form polymeric hydroxide species that coagulate and flocculate contaminants. Simultaneously, electrolytic reactions at the cathode produce hydrogen micro-bubbles that assist flotation. EC is particularly effective for emulsified oils, stable colloids, and situations where external chemical dosing is undesirable or supply is unreliable.

No External Chemicals

Coagulant generated in-situ from anode dissolution – no ferric, alum, or polymer delivery needed.

Reduced Sludge Volume

EC sludge is denser and more dewaterable than chemical coagulation sludge – 40% less volume.

Disinfection Side Effect

Electrolytic reactions generate oxidative species that reduce bacterial counts by 2-4 log.

Precise Control

Coagulant dose controlled by current density (A/m2) – digital ammeters provide real-time control.

Process Steps

Step-by-step breakdown of the treatment process from influent to effluent.

01

Wastewater Equalization

Flow and pH equalized to provide stable conditions for EC. Optimal pH range 5.0-8.0 for iron anodes, 5.0-7.5 for aluminium.

02

Electrocoagulation Cell

Rectifier supplies DC current (10-50 A/m2) to parallel plate electrodes. Iron anodes dissolve at 1 g/Ah. Contact time 15-45 minutes.

03

Flocculation Chamber

Gentle mixing for 10-20 minutes allows Fe(OH)3 or Al(OH)3 flocs to grow and enmesh contaminants. Polymer may be added for heavy loads.

04

Flotation/Settling

Hydrogen micro-bubbles from cathode rise at 0.3 m/h, carrying flocs to surface. Alternatively, lamella clarifier captures settling flocs.

05

Sludge Removal & Effluent

Float skimmed or sludge scraped. Effluent filtered through sand or cartridge to capture carryover. Final pH adjusted if needed.

Typical Performance

90%
Oil removal
80%
COD reduction
95%
Heavy metals removal
40%
Less sludge vs chem coag

Equipment Used in This Process

Explore the equipment components that make this process effective.

Where This Process is Applied

Oily Wastewater

Break petroleum and food oil emulsions without demulsifying chemicals.

Landfill Leachate

Remove humic acids, heavy metals, and ammonia from leachate.

Chemical Effluent

Treat process wastewater containing colloidal silica and organics.

Food & Dairy

Remove fats and proteins from high-strength food processing waste.

Related Processes & Technologies

Process Fundamentals & Design

This treatment stage is engineered to achieve specific contaminant removal targets while providing stable, predictable performance across variable inlet conditions. Design parameters are calculated from wastewater characterisation data, regulatory requirements, and site-specific constraints including footprint, energy availability, and operator capability.

Process Optimisation

Design validated by CFD modelling and pilot testing to confirm performance guarantees.

Mechanical Reliability

Equipment selected for 20-year design life with minimal wearing parts and easy access.

Chemical Efficiency

Automated dosing and feedback control minimise reagent consumption and sludge production.

Compliance Assurance

Online monitoring and data logging demonstrate continuous consent compliance.

Design Parameters

Design Flow10 – 5,000 m³/h (application specific)
Inlet VariabilityDesigned for 1:3 peak-to-average flow ratio
Removal Efficiency85 – 99% depending on target contaminant
Hydraulic RetentionCalculated from kinetic constants and safety factors
Power Consumption0.5 – 5.0 kWh/100 m³ (process dependent)
Chemical DoseAuto-controlled based on online analysers
Sludge Production0.2 – 1.5 kg DS/kg contaminant removed
MaterialsSS304, SS316L, or carbon steel with coating

Integration with Treatment Train

No treatment stage operates in isolation. This process is designed to receive conditioned influent from upstream stages and deliver effluent quality suitable for downstream processes. Hydraulic and organic loading rates are balanced across the complete treatment train to prevent bottlenecking and ensure overall plant efficiency. Our engineers model the complete flowsheet to optimise Capital expenditure and Operating expenditure across the plant lifecycle.

Upstream Protection

Screening, equalisation, and pre-treatment protect this stage from damage and overload.

Downstream Conditioning

Effluent quality ensures downstream biology, filtration, or disinfection performs optimally.

Recycle Streams

Reject streams, filtrate, and centrate are routed back to appropriate upstream points.

Need This Process for Your Application?

Our engineers design and commission complete treatment systems including all equipment, automation, and commissioning support.

Industries We Serve

Our expertise spans multiple industries with sector-specific water treatment solutions.