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Water Pollution Prevention

Wastewater Treatment

In 2021, the total wastewater discharge was about 18.71 million metric tons, which is 1.3% lower than in 2020, and the discharge intensity per unit of revenue was reduced by 18%. In 2021, the wastewater discharges from our plants in Taiwan and Mainland China were about 13.6 million metric tons and 5.12 million metric tons respectively, accounting for 73% and 27% of the total discharge.

After treatment, the wastewater from our plants in Taiwan will be legally discharged into the streams and incorporated into the local sewage treatment plants, including Nankan River, Laojie River, Dongmen River, and Xinfeng River. The wastewaters from our plants in Mainland China are discharged to the local exclusive sewage treatment plants, and after treatment, they are finally legally discharged to Maozhou River, Wusong River, and Taicangtang.

To confirm the results of wastewater treatment, we actively review and improve the plants’ wastewater pollution prevention system. At present, the discharge levels of our plants in Taiwan and Mainland China are far below the approved standards of local regulations (COD approved standards 3,688 tons、Cu approved standards 159 tons). We take the initiative to publish quarterly third-party testing data on wastewater discharge and explain the wastewater treatment process on the Company’s official website. The wastewater discharge standards in Taiwan have been tightened following future environmental protection laws and regulations. The efficiency of existing wastewater treatment facilities is under evaluation and the current conditions can meet future emission standards. To avoid the impacts of stricter environmental protection laws and regulations, we will continue to invest in efficiency improvement and expansion of wastewater treatment facilities, reduce source pollutants, and develop internal wastewater discharge control standards that are superior to laws and regulations to reduce impacts from environmental pollution, operations, and production.

Wastewater Discharge and Intensity


Emission Destination








Groundwater Body and Local Sewage Treatment Facility







Mainland China

Local Sewage/Treatment Facility












Total Wastewater Discharge Intensity

m3/Million Revenue






Note: The above data does not include Chungyuan Plant, Chung Hsing Plant, Yangmei Plant and Shanying II Plant in Taiwan.

Reduction Projects and Results

Wastewater diversion into biological treatment,Increase capacity of wastewater plants,Reduce energy consumption of subcontracted processing

In addition tothe production of copper-containing waste liquid in the printed circuit board manufacturing industry, film-removing waste liquid also accounts for a large amount. The company's wastewater treatment process adopts a chemical coagulation system, which is mainly used for the treatment of copper-containing waste liquid, and its ability to treat COD is poor. In the past, the treatment method of film-removing waste liquid was to pass the waste liquid through the aeration and stratification system, and then outsource the high-concentration film-removing waste liquid; the low-concentration waste liquid was discharged into the waste water plant for self-treatment. When the company's production capacity increased, the waste liquid When the treatment capacity reaches the load of the wastewater plant and cannot continue to stratify, the stock solution will accumulate and need to be cleared and transported by outsourcing, which will increase the cost of outsourcing treatment. The company's 2020 project introduced the method of contacting biological filter materials, using biofilms to treat COD in water under an aerobic state, and successfully increased the capacity of waste water plants to treat COD waste liquid, increasing 1.77 tons per day, and a total of 53.1 tons per month. Reduce the cost of outsourced cleaning and transportation, increase the capacity of the wastewater plant to treat COD waste liquid, and avoid the discharge of COD-containing wastewater into the environment to increase the environmental load and affect the ecological environment.

Waste Water Quality Monitoring

In order to monitor the water quality at any time, set up a continuous monitoring system and connect with the Environmental Protection Administration to monitor the water temperature, pH, conductivity, COD, and SS in real time.

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