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Wastewater from electroplating and electronic component manufacturing contains metals, salts and chemicals at concentrations that many conventional systems cannot treat. In return, the industry has a clear reason to reuse water: rinse water after plating must be of high quality, and pure water is expensive. NGO International Co., Ltd (NGO International), an industrial wastewater and pure water company, has delivered a treatment station that treats the wastewater, recovers precious metals and reuses plating wastewater for an electronic component factory. The sections below cover the characteristics of the wastewater and two real cases.
Overview of electroplating wastewater treatment
Electroplating wastewater consists of several streams with very different properties. Rinse water after plating has a large flow but is dilute, containing dissolved metals together with mild acid or alkali. Spent solutions from plating and pickling baths have a small flow but are highly concentrated, and may contain cyanide, hexavalent chromium or complexing agents that make metals hard to precipitate. For electronic components, semiconductors and circuit boards there are also streams containing copper, nickel, zinc, chromium and precious metals.
Operating costs are concentrated mostly in metal sludge and salinity. Metal precipitation generates a lot of sludge, which usually has to be managed as hazardous waste; water after preliminary treatment is still high in salts, so it is hard to reuse without membrane filtration or ion exchange. When the streams are mixed together, complexing agents and cyanide make treatment even harder. Precious metals carried away in the wastewater are also raw material going to waste.
Design therefore starts with stream segregation: identifying which streams can be reused, which need metal recovery, and the water quality required for each purpose, for example final rinse water needs low conductivity.
NGO International’s capabilities in electroplating wastewater treatment
NGO International designs wastewater treatment and pure water systems for electroplating plants and for factories making electronic components, microchips, semiconductors and PCBs, with a focus on water reuse and recirculation. Our scope runs from survey and proposal to installation, commissioning and technical support during operation. For new factories, NGO also supports the EIA report and the environmental permit.
Post-investment support is what NGO emphasises in this industry, because many factories use foreign machinery and technology and find it hard to get timely technical support, especially when a problem occurs. NGO supplies materials, chemicals and technical advice from its two offices in Hanoi and Ho Chi Minh City. The solutions for the industry are collected on the page wastewater treatment and pure water solutions for electroplating and electronic components manufacturing.
Featured projects of NGO International
The video at the top of the page goes through the technology diagram and each equipment area of the first station; the second case comes from a customer testimonial on the Projects page. The location, capacity and company names are not disclosed.
Plating wastewater treatment and reuse station for an electronic component factory
| Industry | Electronic components with a plating process |
|---|---|
| Objective | Treatment, precious metal recovery, water reuse |
| Technology | Carbon adsorption, micro-filtration, RO, ion exchange, demineralisation |
| Layout | Chemical area, operating corridor, control house |
- The challenge
The plating wastewater had to be treated clean enough to return to production, reducing the amount of fresh water drawn in, while recovering the precious metals that were being discharged with the water.
- NGO’s solution
The line consists of a holding tank and an activated carbon adsorption tank, a micron-size filtration system, an RO unit, and an ion exchange and demineralisation area; the chemical area, operating corridor and control house are laid out separately for safe operation.
- NGO’s role
NGO International delivered this plating wastewater treatment and reuse station for the electronic component factory.
- Results / value delivered
The station recovers treated water for suitable reuse purposes within the factory, reducing fresh water intake and the wastewater that must be discharged to the environment.
Water reuse solution for an electronic component manufacturer
| Industry | Electronic component manufacturing |
|---|---|
| Objective | Reuse at least 50% of the water |
| Year | 3 years in use (according to customer feedback) |
| Monitoring | Stably meets QCVN 08:2023/BTNMT |
- The challenge
The company set a target of reusing at least 50% of its water for production.
- NGO’s solution
NGO International’s water reuse solution; the detailed configuration is not disclosed.
- NGO’s role
Supplier of the water reuse solution, which the company has used continuously for three years.
- Results / value delivered
According to the company’s head of engineering, all water monitoring results have stably met QCVN 08:2023/BTNMT (the national technical regulation on surface water quality) throughout the period of use. The feedback is posted on the Projects page.
Wastewater treatment technologies commonly applied in the electroplating industry
Stream segregation comes first. Dilute rinse water is separated from concentrated solutions; streams containing cyanide or hexavalent chromium are pretreated separately (cyanide oxidation, chromium reduction) before entering the common system.
Metals are precipitated as hydroxides or sulphides through pH adjustment and chemicals, followed by coagulation–flocculation, settling and filtration. Activated carbon adsorbs organic matter and residual chlorine ahead of the membrane steps, protecting the membranes.
For reuse, micro-filtration removes fine particles, RO retains salts and dissolved ions, and ion exchange and demineralisation bring conductivity down to the level the rinse water requires. Ion exchange is also a way to capture metals from dilute streams for recovery. The concentrate stream from RO needs separate treatment, something that is often overlooked when calculating the reuse rate.
Electroplating wastewater treatment in Vietnam
Electronic component factories are usually located in industrial parks, where the management board sets connection limits and may require separate monitoring. Plating facilities outside industrial parks discharge in line with the technical regulation and their environmental permit, and must also manage metal sludge separately as hazardous waste.
Foreign-invested factories often have their own corporate targets for water reuse and environmental reporting, so the reuse target should be fixed in numbers from the start, such as the 50% minimum in the case above.
In Northern Vietnam, NGO International undertakes the treatment and reuse of plating wastewater for electronic component and semiconductor factories in the provinces below. Bac Ninh, Bac Giang and former Vinh Phuc are home to many foreign-invested electronics factories; Hai Phong and Hanoi also have many high-tech industrial parks.
Where we work: electroplating and electronic components wastewater
Northern Vietnam: Bac Ninh, Bac Giang (now part of Bac Ninh), Vinh Phuc (now part of Phu Tho), Hai Phong, Hanoi
Why choose a contractor with real experience?
A water reuse system in the electroplating industry is under pressure from two sides: rinse water quality directly affects the product, while wastewater quality affects compliance. Three questions help screen contractors: do they segregate streams before designing, has the expected reuse rate already excluded the RO concentrate stream, and who is responsible when the conductivity of the recycled water exceeds the requirement.
It is also worth looking at the ability to provide technical support after handover. Membranes and ion exchange resin must be replaced and regenerated on schedule, and plating bath composition changes with the product, so an experienced contractor will adjust operation rather than stop at acceptance; this is also part of the operation consulting service that NGO provides.
Frequently asked questions
NGO International has delivered a treatment and reuse station for plating wastewater at an electronic component factory, with activated carbon adsorption, micro-filtration, RO, ion exchange and demineralisation steps.
Yes, if the streams are segregated and pass through suitable filtration, RO, ion exchange and demineralisation steps. One NGO customer set a target of reusing at least 50% of its water and has had stable monitoring results for three years.
Stream segregation, cyanide and chromium pretreatment, metal precipitation, coagulation–flocculation and settling, filtration and activated carbon adsorption; for reuse, add micro-filtration, RO, ion exchange and demineralisation.
Because cyanide, hexavalent chromium and complexing agents need separate pretreatment; mixing them reduces the efficiency of later steps and increases sludge.
Yes, when the metal-bearing streams are separated and captured by ion exchange or other suitable methods. NGO’s station for the electronic component factory was designed to both reuse water and recover precious metals.
In Northern Vietnam, NGO takes on projects in Bac Ninh, Bac Giang (now part of Bac Ninh), Vinh Phuc (now part of Phu Tho), Hai Phong and Hanoi, where many electronic component and semiconductor factories are concentrated.
Metal sludge must be dewatered, analysed for classification and transferred in accordance with regulations; it usually falls into the hazardous waste group.
QCVN 08:2023/BTNMT is the technical regulation on surface water quality, while industrial wastewater discharged into the environment must meet QCVN 40:2025/BTNMT. Companies can use QCVN 08:2023 as a benchmark for the quality of reused water, as the customer above did.
Conclusion
The electroplating and electronic components industry shows that water reuse can be a realistic goal, provided the wastewater is segregated correctly and the filtration, RO and ion exchange steps are planned together with metal treatment. Metal sludge and the concentrate stream are the two items that must be accounted for at the design stage.
NGO International has delivered a station that treats wastewater, recovers precious metals and reuses plating wastewater for an electronic component factory, and has a customer in the industry whose monitoring results have remained stable for three years. For a factory considering water reuse, the first step is to segregate the streams and measure each one, and only then assess with NGO the feasible level of reuse.
Talk to an NGO engineer
Free survey and consultation. Send us your wastewater type (industrial or domestic), flow rate (m³/day), influent analysis results if available and required effluent quality; an NGO engineer will propose a suitable technology and a realistic quotation.
Offices in Hanoi and Ho Chi Minh City · +84 24 7300 0890 · office@8ngo.com
