Under the framework of Vietnam's Clean Air Action Plan, the steel industry is leveraging technological innovation to address the challenge of PM2.5 control. As a key sector for industrial emissions, Vietnamese steel enterprises are gradually moving from "compliance emission" to "ultra-low emission" through process upgrading, intelligent management, and international cooperation, setting a benchmark for the green transformation of manufacturing in Southeast Asia.

Policy-driven technological innovation has become the key to breaking the deadlock. Vietnam's Ministry of Industry and Trade has clearly required steel enterprises to complete ultra-low emission transformation by 2025. Formosa Ha Tinh Steel took the lead in investing 1.2 billion US dollars in building a sintering flue gas purification system, controlling particulate emissions within strict standards. Hoa Phat Dung Quat, a leading enterprise, has joined hands with Chinese companies to create a demonstration project. Its Phase II project adopts Longking Environmental's dry ultra-clean + device, and through the combined process of "activated carbon adsorption + SCR denitrification + bag filter", the dust emission is far below China's ultra-low standards. The pre-charged bag filter technology of Sinosteel Tiancheng further improves the particulate capture accuracy to an internationally leading level, and this technology has been applied on a large scale in Vietnamese steel enterprises.

Full-process management and control build an all-round pollution control system. In the treatment of organized emissions, Hoa Phat Dung Quat's 300-ton converter is equipped with SMS Group's dry electrostatic precipitator system, with dust emissions below 20mg/Nm³; the steel slag treatment link adopts the "pressurized thermal insulation + dust removal" technology, which handles 680,000 tons of steel slag annually while keeping the particulate concentration <10mg/m³. The treatment of unorganized emissions has further formed a "three-dimensional prevention and control network": after the raw material yard was transformed into a fully enclosed greenhouse, the surrounding particulate concentration dropped from 0.8mg/m³ to 0.3mg/m³; high-pressure dust control fog cannons are installed along the transfer belt corridor, and through rotating nozzles with adjustable spray angles, fine water mist of ≤100μm is evenly distributed over the operation area to accurately capture PM2.5 raised during loading and unloading, reducing the dust concentration in local areas by an additional 40%; fixed dust control fog cannons are also installed on both sides of the factory roads, cooperating with mobile dust control fog cannon vehicles for patrol operations, building a dynamic dust suppression line of "fixed + mobile", which effectively suppresses secondary dust generated by vehicle movement.

Intelligent management and policy coordination strengthen the pollution control line of defense. Vietnamese steel enterprises generally have established an "online monitoring + grid monitoring" system, installing CEMS (Continuous Emission Monitoring System) at key points such as sintering and converters. They even include the operating status of dust control fog cannons in the monitoring platform, adjusting the spray duration and frequency based on real-time data to balance dust suppression effects and water resource utilization efficiency. Hoa Phat Dung Quat has introduced SMS Group's Data Factory system, which optimizes the production process through data analysis and indirectly reduces dust generation. Environmental policy dividends further stimulate the motivation of enterprises: qualified enterprises can enjoy a 50% reduction in environmental protection tax, and green credit policies further ease the financial pressure of transformation.

From Formosa Ha Tinh Steel's flue gas purification system to Hoa Phat Dung Quat's "dust control fog cannon + full-process pollution control" solution, Vietnam's steel industry has proven through practice that PM2.5 control and industrial upgrading can advance simultaneously. In this green transformation, the in-depth integration of Sino-Vietnamese environmental protection technology cooperation not only safeguards the blue sky and white clouds of Vietnam but also writes a vivid footnote for the green development of the "Belt and Road Initiative".