Earthing Chemical Compound Materials House & Industrial company

Chemical earthing systems use specialized backfill compounds to reduce soil resistivity and maintain moisture. The composition varies between traditional methods and modern maintenance-free "chemical" mixtures.

1. Modern Chemical Backfill Compounds

These are "maintenance-free" mixtures designed to be non-corrosive and highly conductive. Common ingredients include:

• Bentonite Clay: A sodium-activated montmorillonite clay that can swell up to 13 times its dry volume. It acts as a moisture retainer and ensures tight contact between the electrode and the soil.
• Graphite/Carbon: Used in 15%–35% concentrations to provide high electrical conductivity. Graphite is often used in premium compounds like Marconite for its superior conductive properties.
• Ionic Chemicals: Often a combination of Sodium Chloride (4%–6%) and Potassium Chloride (19%–31%) to facilitate easy electricity conduction.
• Gypsum (Calcium Sulfate): Sometimes mixed with bentonite (typically 75% gypsum to 20% bentonite) to improve moisture retention without excessive shrinking during dry seasons.
• Sodium Sulfate: Added in small amounts (approx. 5%) to prevent polarization of the earth electrode by removing gases formed during current discharge.
• Binding Agents: Some manufacturers add silicates or bonding resins to help the compound solidify and stick to the electrode.

2. Traditional Earthing Composition

The conventional method uses a layering technique in a large pit:

• Charcoal: Used to hold water and maintain moisture around the electrode for long periods.
• Salt (Sodium Chloride): Added to increase the conductivity of the soil.
• Note: This method is being phased out because salt is corrosive to electrodes and can leach away, requiring regular maintenance.

3. Electrode Material Composition

The "chemical" aspect also refers to the electrode types used with these compounds:

• Copper-Bonded Steel: A steel core with a thick molecularly bonded copper coating for high conductivity and corrosion resistance.
• Galvanized Iron (GI): Iron pipes or plates coated with zinc, used in less corrosive or budget-sensitive environments.
• Pipe-in-Pipe: Two concentric pipes where the gap is filled with the conductive backfill compound to increase surface area.