Electric Tar CatcherIt Is A Device That Uses High-voltage Electric Fields To Purify Tar Particles In Industrial Waste Gas, Widely Used In Industries Such As Coking, Coal Gas, And Asphalt. Its Core Principle Is Based On Gas Ionization And Charged Particle Adsorption, And The Specific Process Can Be Divided Into The Following Three Key Stages:
1、 Establishment Of High Voltage Electric Field
The Device Core Consists Of A Bipolar System:
Corona Electrode: Located At The Center Of The Electric Field, Usually A Thin Metal Wire (such As Nickel Chromium Wire, Lead Wire) Or Needle Punched Electrode, Connected To The Negative (or Positive) Pole Of A High-voltage DC Power Supply, Which Releases A Large Number Of Electrons During Operation.
Precipitation Electrode: As The Positive (or Negative) Electrode Of An Electric Field, It Is Usually A Metal Cylinder, Flat Plate, Or Honeycomb Structure, Connected To The Equipment Housing And Grounded. When A High-voltage Power Supply (usually With An Output Voltage Of 30-60kV) Is Connected, A Non-uniform High-voltage Electric Field Is Formed Between The Corona Electrode And The Precipitation Electrode - The Electric Field Strength Near The Corona Electrode Is Extremely High (up To 10 ⁶ V/m Or More), While The Electric Field Strength Near The Precipitation Electrode Is Relatively Low. This Electric Field Distribution Is The Basis For Subsequent Ionization And Adsorption.
2、 Gas Ionization And Electron Collision
Under The Action Of A Strong Electric Field, The Gas Around The Corona Electrode (mainly Nitrogen, Hydrogen, Methane, Etc. In The Exhaust Gas) Will Undergo Ionization: The High-energy Electrons Released By The Corona Electrode Collide With Gas Molecules, Causing Them To Lose Electrons And Become Positively Charged Ions, While Generating New Free Electrons (this Process Is Called "avalanche Ionization"). Eventually, A "corona Zone" Filled With Positive And Negative Ions And Free Electrons Is Formed Around The Corona Electrode (appearing As A Faint Blue Light, Visible To The Naked Eye), And The Area Expands With Increasing Voltage. At This Time, Tar Particles (usually With A Diameter Of 0.1-10 μ M) In The Exhaust Gas Enter The Electric Field With The Airflow And Collide With Ions And Electrons In The Corona Zone, Thus Carrying Charges (mostly Negative Due To Faster Electron Migration Speed).
3、 Adsorption And Separation Of Charged Particles
Under The Action Of Electric Field Force (Coulomb Force), Charged Tar Particles Will Move Towards The Opposite Polarity Precipitation Electrode: Negatively Charged Tar Particles Are Attracted To The Surface Of The Positively Charged Precipitation Electrode, Lose Their Charge And Adhere To It, Gradually Aggregating Into Larger Tar Droplets. When The Gravity Of The Droplet Exceeds Its Adhesion To The Surface Of The Precipitation Electrode, It Will Flow Down Along The Precipitation Electrode Wall And Eventually Be Collected Through The Tar Discharge Outlet At The Bottom (which Can Be Recycled Or Further Processed).
4、 Key Supplement: Electric Field Differences In Different Structures
The Structure Of Electric Tar Precipitators (such As Tube, Plate, Honeycomb) Can Affect The Uniformity Of The Electric Field And The Efficiency Of Coke Removal, But The Core Principle Remains The Same:
Tube Type: The Sedimentation Electrode Is A Circular Metal Tube, And The Corona Electrode Is Located At The Center Of The Tube. The Electric Field Distribution Is Uniform, Making It Suitable For Treating Exhaust Gases With Small Tar Particles.
Honeycomb Type: Composed Of Multiple Hexagonal Honeycomb Units, With A Consistent Distance Between The Precipitation Electrode And The Corona Electrode, High Space Utilization, And A Defocusing Efficiency Of Over 95%.
Regardless Of The Structure, Its Core Is To Achieve A Closed Loop Of "ionization → Charging → Adsorption" Through A High-voltage Electric Field, Thereby Separating Tar Particles From Exhaust Gas And Achieving Purification Purposes.
