Working Principle of Oil Fume Filter
The core working principle of an oil fume filter relies on the coordinated whole process of "Capture – Separation – Purification" to separate oil mist particles, odors and other pollutants from the air, so as to meet emission standards. It adopts a layered treatment mechanism with different technical solutions, which can be divided into mainstream technical principles and general working procedures.
I. Mainstream Technical Principles (Classified by Application Scenarios)
Electrostatic Type (Dominant Product, Leading the Market)
A high-voltage generator creates a high-voltage electrostatic field. Oil fume particles get ionized and charged inside the electric field. Under electric field force, the charged particles are adsorbed onto collecting plates with opposite electric charges and condense into oil droplets, which are then collected by an oil sump before clean air is discharged.
Its purification efficiency can exceed 90%–95%. It fits heavy oil fume conditions. Frequent replacement of consumables is unnecessary, yet the electric field needs regular cleaning.
Mechanical Filtration Type
It adopts multi-stage interception with "primary filtration + medium filtration + high-efficiency filtration". The primary filter layer (metal mesh, non-woven fabric) traps large oil fume particles and food residues. Medium and high-efficiency filter screens (glass fiber, synthetic fiber) capture tiny oil fume particles via physical interception and inertial collision.
Its purification efficiency is relatively low (20%–92% when used alone). The filter screens need regular cleaning or replacement, and this model is mostly used for pre-treatment.
Photocatalytic Oxidation Type
Ultraviolet lamps with specific wavelengths (185nm, 254nm) work with catalysts such as titanium dioxide to generate strongly oxidative substances. These substances decompose organic pollutants and odor molecules in oil fume into carbon dioxide and water.
This technology focuses on odor elimination and has limited effect on large oil fume particles. UV lamps require periodic replacement, and this unit is suitable for scenarios with strict odor control requirements.
Composite Type (Electrostatic + Filtration / Photocatalysis)
It integrates advantages of multiple technologies. Large particles are first trapped by mechanical filtration, then fine particles and odors are removed through electrostatic adsorption or photocatalytic decomposition.
The purification efficiency can reach over 95%. It adapts to complex oil fume working conditions and only needs modular maintenance.
II. General Working Procedures
1. Capture Stage
The fan generates negative pressure to draw oil fume from sources such as stoves and industrial furnaces into the filter and prevent fume diffusion. Centralized collection via pipelines or independent direct adsorption can be adopted to avoid oil fume leakage.
2. Separation Stage
Different separation methods are applied according to technical types: electrostatic adsorption by electric field charging for electrostatic models, mesh interception for mechanical filters, and UV decomposition for photocatalytic equipment.
The key is to efficiently separate oil mist particles and organic contaminants from air. Some technologies enable liquefaction and recovery of oil droplets.
3. Purification & Discharge Stage
After layered treatment, purified air can be discharged indoors or outdoors in compliance with emission standards. Separated oil waste is collected in oil sumps for centralized disposal to prevent secondary pollution.
For photocatalytic equipment, pollutants are directly broken down into harmless substances without residual oil contamination.
