YIHUA Vietnam DAF Industrial Wastewater Treatment Project

1. Project Background

Vietnam has emerged as a key manufacturing hub in Southeast Asia, with a booming electroplating and metal finishing sector concentrated in industrial zones around Ho Chi Minh City. Our client is a leading electroplating enterprise specializing in automotive and electronic components, producing approximately 100m³ of industrial wastewater daily. The wastewater contains heavy metals such as copper and nickel, emulsified oils, organic additives, and fine suspended solids that are difficult to settle.Vietnam’s General Department of Environment (GDE) enforces stringent discharge standards for industrial wastewater, particularly for heavy metals and total suspended solids (TSS), to protect local waterways and ecosystems. The client faced critical constraints: limited on-site space for a traditional civil-constructed treatment plant, and an urgent need to upgrade their system within 50 days to meet new regulatory requirements and avoid production halts.

2. Key Challenges

• Space Limitations: The factory’s compact layout left only 35㎡ of usable space, making conventional, large-scale treatment systems unfeasible.

• Difficult-to-Treat Contaminants: The wastewater contained emulsified oils and fine heavy metal flocs, which are inefficiently removed by traditional sedimentation alone.

• Regulatory Compliance: The new standards demanded near-zero levels of heavy metals and TSS, necessitating highly efficient solid-liquid separation technology.

• Rapid Deployment: The upgrade needed to be completed in 50 days to align with the factory’s production schedule and avoid regulatory penalties.

3. Solution

YIHUA delivered a containerized Dissolved Air Flotation (DAF) integrated industrial wastewater treatment system, custom-engineered to address the client’s specific challenges and align with the equipment shown in the image.

Core DAF Technology: The system uses high-pressure dissolved air water to generate micro-bubbles, which effectively adsorb and float emulsified oils, heavy metal flocs, and fine suspended solids to the water surface, where they are removed by a skimming mechanism.

Modular & Compact Design: The entire system, including chemical dosing (pH adjustment, PAC, PAM), flocculation, DAF separation, and post-filtration, was housed in a pre-fabricated skid-mounted unit, fitting perfectly within the 35㎡ footprint.

Targeted Heavy Metal Removal: A proprietary chemical precipitation process was integrated upstream of the DAF unit to convert soluble heavy metals into insoluble flocs, which are then efficiently removed by the DAF process.

Automated Operation: The system features a PLC-based control system with real-time monitoring of pH, ORP, and TSS levels, enabling unattended operation and reducing labor costs.

Fast Installation: The pre-assembled unit was transported to the site and fully commissioned in just 42 days, 8 days ahead of the regulatory deadline.

4. Project Outcomes

Regulatory Compliance: The effluent consistently meets all GDE standards, with heavy metal concentrations reduced to non-detectable levels and TSS < 10mg/L, eliminating any risk of fines or shutdowns.

Superior Solid-Liquid Separation: The DAF system achieved a 98% removal rate for emulsified oils and fine suspended solids, a significant improvement over the client’s previous sedimentation-only system.

Operational Efficiency: The automated system reduced labor requirements by 65%, and the compact design freed up valuable factory space for production expansion.

Cost Savings: Compared to a traditional civil plant, the total project cost was reduced by 30%, with ongoing maintenance costs cut by 35%.

Sustainability Impact: The treated water is now reused for non-contact cooling and irrigation, reducing the factory’s freshwater intake by 35% and lowering its carbon footprint.