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Asbury Carbon Backfill

Asbury Carbon Backfill

Carbon is Life

Carbon is the basic building block of all organic substances and is therefore the basis of all living things. Because carbon combines readily with oxygen, giving off heat as a by-product, it is also a vital energy source. Carbon is one of the most useful of all chemical elements and Asbury Carbons is the most experienced processor of carbon products for industry today.

Amorphous carbons such as coal, petroleum coke, pitch coke, active carbon and carbon black have unique physical and chemical properties. These properties enable us to process amorphous carbons for a myriad of industrial applications including chemical reducing agents, carbide forming reagents, metallurgical products, cathodic protection materials and adsorbing carbons just to name a few.

Carbon in the form of crystalline graphite possesses a combination of properties including lubricity, refractoriness, chemically inertness, as well as thermal and electrical conduction. These properties make graphite the material of choice for thousands of end-use applications including crucibles, refractories, cements, lubricants, chemical tank linings, powder metal parts, polymer compounds, drilling fluids, electric motor brushes, batteries, artificial diamonds, and others too numerous to mention.

Cathodic Protection — Carbons are Asbury

Asbury uses only the highest quality carbon materials to provide the cathodic protection industry with advanced, engineered materials that provide a combination of properties including high conductivity, resistance to corrosive environments, environmental stability, and easy-pouring and cavity-filling characteristics. These properties and Asbury Carbons’ 100+ years of experience make Asbury cathodic protection grades the experts’ choice.

The Ideal Cathodic Protection

Carbon has anodic properties. When Calcined Fluid Coke, Metallurgical Coke Breeze, or Calcined Petroleum (Delayed) Coke is used as a backfill column, it effectively increases the available anode surface. This means that when carbon backfill is used, the total effective anode surface includes not only the sacrificial metallic component, but also the carbon. This configuration results in less consumption of the metallic anode since the carbon surface can oxidize in its place. Asbury Carbon’s backfill products decrease anode-to-earth resistance, decrease gas blockage and drying tendencies, increase anode life, maintain hole integrity, and prevent cave-in.

The purpose of the coke backfill is to provide an electrical pathway for current flow. It is for this reason that low resistivity, particle size and specific gravity are important backfill properties. Low resistivity  favors electric current flow to the backfill/ground interface. Small particle size and high density favor electric current flow between the anode material and backfill by improving contact between the two.

Asbury Carbons offers a full spectrum of carbon anode backfill products — varying in resistivity, particle size and specific gravity — for applications including conventional beds, top loading, small-diameter wells, deep wells, pumping as slurry and any combination.

Asbury also offers many magnesium backfill formulas as well as bentonite for your backfill purposes.

Grade Designation Nominal Size Carbon % Bulk Density
lbs/cu ft
@150 psi
 Calcined Fluid Coke - 4518  1/4 x 30 Mesh  99.9%  60   .10 Ohm/cm
 Calcined Fluid Coke - 250  4 x 200 Mesh  99.8%  60   .10 Ohm/cm
 Calcined Fluid Coke - 251  20 x 200 Mesh  99.8%  65   .10 Ohm/cm
 Calcined Fluid Coke - 251P  20 x 200 Mesh  99.8%  65   .10 Ohm/cm
 Metallurgical Coke Breeze - 4649  1/4 x 0  88.5%  40   .15 Ohm/cm
 Calcined Petroleum (Delayed) Coke - 218-L  3/8 x 1/8  99.0%  45   .10 Ohm/cm
 Calcined Petroleum (Delayed) Coke - 218-R  6 x 12  99.0%  45   .10 Ohm/cm
 Calcined Petroleum (Delayed) Coke - 218-F  3/8 x 0  99.0%  45   .10 Ohm/cm
 Calcined Petroleum (Delayed) Coke - 218-XF  28 Mesh x 0  99.0%  60   .10 Ohm/cm