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Bone Charcoal for Gun Case Hardening and Bluing

Ebonex offers two granulationís of bone charcoal for gun case hardening and gun bluing. We can offer our customers a 10x28 mesh grade, and a 5x8 mesh grade (number 6 granulation). These grades are produced by using the hard bones of cattle, which are washed, de-tallowed, crushed and finally charred in a retort furnace. By using a retort furnace, a fine quality of bone charcoal is achieved. In this process, charring can take place without excess amounts of oxygen giving a rich black pigmentation.

Bone Charcoal in Soil Enhancement Applications

Bone Charcoal Fines are derived from the manufacture of New Animal Charcoal - a carbonaceous adsorbent widely used in the Sugar Refining and Water Treatment Industries. The product is manufactured from selected grades of cattle bone carbonized at temperatures between 700°C and 1000°C for a total period of around 12 hours. Hence, the final product is virtually sterile, suitable and, indeed, safe for use in food industry applications.

The Bone Charcoal Fines are of a particle size - below 40 mesh - and contain carbon (about 10 percent) on a Hydroxyapatite matrix. Hydroxyapatite is a calcium phosphate compound (Ca10(PO4)6(OH)2 and therefore , is a good source of both phosphate and calcium.

A typical analysis of bone char fines is as follows:

Total Phosphate (as P2O5) 30%
Carbon Content 10%
Moisture Content below 5%
Screening Analysis
   Retained on 35 mesh
   Retained on 60 mesh
   Retained on 100 mesh
   Passes 100 mesh

Bone Charcoal Fines has a unique buffering capacity, resulting in the material imparting alkalinity to aqueous solution.

The product is being used as a fertilizer in hill/grassland application and can be used mixed with other ingredients to produce specific fertilizer products for both agricultural and horticultural applications. Tests by third parties has indicated that Bone Charcoal Fines, when included in proprietary blends, can enhance the availability of nutrients to plants.

Fish Farming with Bone Char

The rearing of fish in captivity in fish farms is an important and growing industry - not just in the United Kingdom, but throughout the world.

Since fish are entirely dependent on water for their very existence, it follows that water quality plays an important role in the success, both technically and economically, of such ventures.

In fish hatcheries, the quality of incoming water is of paramount importance whether or not the water is sea water, fresh water from a private water source, or from a municipal supply. Indeed, even municipal water supplies can contain substances which are detrimental to fish e.g. metals such as aluminum, lead, copper and iron; fluoride, chlorine, and certain organics and herbicides/pesticides.

In on-growing stations too, water treatment is often required, particularly on land based farms and, in many instances, water is re-cycled. In hatcheries, recycling and filtration is also common practice. There is a requirement, in such situations, to remove decaying food matter, coloring derived from food and medicines, and excrement etc. from the water.

This is a natural charcoal especially for water treatment and this new product has much to offer to the fish farming industry.

Charcoal is capable of removing color, taste and odor from water, together with a wide range of heavy metals such as lead, cadmium, mercury, silver, aluminum, copper, nickel, zinc and iron etc. The new natural charcoal can also remove fluoride, chlorine and certain organics.

In trials conducted by Polytechnic South West, charcoal was tested in a system containing 5000 liters of sea-water in a 100% re-circulation unit. The temperature was maintained at 200°C and the tanks were stocked with Gilthead Sea Bream. The flow rate of the system was 40 liters per minute. The charcoal was installed in a flow-through filter container situated after the mechanical and biological filters in order to give the water a final cleansing prior to its return to the stock tanks. This meant that all of the water had to pass through the filter. The amount of charcoal used was 19.5 kgs. Prior to the trial the water had a distinct yellow discoloration, although all of the water quality parameters were within the limits required for fish survival. This color was more of an aesthetic problem, rather than a water quality one, and was due to leaching pigments from the fish food.

Water samples were taken before the start of the experiment, and regularly throughout, and analyzed spectrophotometrically for absorption between the wavelengths of 400-500 nm. The results were expressed as a percentage of the original, non-charcoal filtered water. It was observed that over 75% of the color was removed on average during the trial and, for part of the time, over 90% removal was achieved.

A similar trial was also performed on a smaller 300 liter sea water re-circulating unit. This used 5.25 kg of washed charcoal placed in a mesh bag inside the mechanical filtration area of the filter system. In this way, the water flowed over the bag without any impedance. The charcoal cleared the water of discoloration within a few hours and maintained the water in this condition for a considerable period of time. The results of these trials indicated that natural bone charcoal was very effective in removing discoloration from re-circulating water systems. Although difficult to quantify, there was a noticeable decrease in the odor often associated with such holding systems.

Additional studies undertaken by the company reveal that the new charcoal can remove Tributyl Tin oxide, Dichlorvos (Nuvan), Malochite green and certain other toxins which can be detrimental to the well-being of fish.

Charcoal has a long history of use within the sugar refining and other food industries and currently carries the approval of the Water Directorate as being safe for use in the treatment of municipal water supplies.

Bone Charcoal in Water Treatment

As a result of research studies undertaken during the current decade, it has been shown that bone charcoal is effective in removing and/or reducing the levels of many contaminants often found in water. These contaminants include, taste, odor, color and certain organic contaminants. However, much more importance is attached to the fact that bone charcoal is efficient in reducing levels of many heavy metals from water, for example: lead, cadmium, mercury, iron, copper, manganese, zinc, aluminum, nickel, and arsenic. Additionally, the material can also adsorb chlorine and fluoride and many of the organo-chloro pesticides and herbicides. The use of bone in removing radio-nuclides is also documented.

Mode of Use

Bone charcoal in its granular form can be used in various types of filtration, for example, in a rapid gravity filter, pressure filters, or in a slow sand filter. The material con be used exclusively on its own or incorporated in a mixture with other media. Flow can be upward or downward. Alternatively, powdered bone charcoal can be added to water contained in a suitable tank for 30 minutes to 2 hours, and removed by a suitable filtration system.


Bone charcoal can be used in the treatment of municipal water, private water, and industrial water.

Some typical examples:

  • Taste and odor removal
  • Color removal
  • Lead removal
  • Heavy Metal removal
  • Effluent treatment
  • Fluoride removal
  • Radio-nuclides reduction
  • Fish Farming applications