SAF Flue Gas Purification System Fume Treatment Plant High Efficiency

During the smelting process, electric arc furnaces generate large amounts of high-temperature, high-dust-content flue gas, which must be equipped with efficient dedusting systems to meet environmental emission requirements.

Baghouse dust collectors are the mainstream equipment for arc furnace dust removal, achieving dust removal efficiencies exceeding 99.5% and controlling outlet emissions to ≤10 mg/m³ or even lower. Common filter bag materials include PPS (temperature resistance 200-220°C), glass fiber (temperature resistance 260-300°C), and PTFE.

Baghouse Dust Collector

Working Principle:
(1) Gravitational settling – When dust-laden gas enters the baghouse, larger and heavier dust particles settle under the action of gravity, similar to the function of a settling chamber.
(2) Sieving effect – When the diameter of dust particles is larger than the gaps between filter material fibers or the gaps between dust particles accumulated on the filter material, the dust is blocked and retained as the gas flows through. This is called the sieving effect. As dust accumulates on the filter material, this effect becomes more pronounced.
(3) Inertial force effect – As the gas flows through the filter material, it can bypass the fibers, while larger dust particles, driven by inertial force, continue moving in their original direction and thus collide with and are captured by the filter material.
(4) Thermal motion effect – Small, lightweight dust particles (below 1 micron) move with the gas flow, closely following the gas streamlines and able to bypass the fibers. However, upon colliding with gas molecules undergoing thermal motion (Brownian motion), they alter their original path, increasing the chance of contact with the fibers and thus being captured. The finer the filter material fibers and the lower the porosity, the higher the capture rate, making it more conducive to dust removal.

Core Structure:

• Casing: Consists of the upper casing (clean air chamber), middle casing (filter chamber), and lower casing (hopper).

• Filter Bag Assembly: Filter bags and bag cages, featuring a self‑locking device for easy replacement.

• Flow Guide Device: Flue gas distributor to prevent dusty gas from directly impacting the filter bags.

• Pulse Jet System: Electromagnetic pulse valves and nozzle pipes for periodic dust cleaning.

• Control System: PLC control panel, thermometer, differential pressure detection device.

• Offline Protection System: Bypass valve, filter bag leak detection device, over‑temperature protection.

Baghouse dust collectors have long been widely used across various industrial sectors to capture non-adhesive, non-fibrous industrial dust and volatile substances, capable of capturing dust particles as small as 0.1 microns. However, when treating gases containing water vapor, care must be taken to avoid condensation issues. Baghouse dust collectors offer high purification efficiency, achieving over 99% efficiency even for capturing fine dust, with exceptionally high performance.

Baghouse dust collectors dominate SAF dust removal, with main advantages including:

High Efficiency: Captures over 99% of particulate matter smaller than 0.1μm, with outlet concentrations controllable below 10mg/Nm³

Strong Adaptability: Insensitive to dust characteristics (specific resistance, stickiness)

High Recovery Value: Recovers high-purity microsilica (SiO₂ content >92%) with economic value

Mature Technology: Low-pressure pulse and long-bag technologies widely adopted in mineral electric furnaces
 

6300kVA SAF Dedusting System Parameters
Based on a design scheme for a 6300kVA semi-closed SAF