Pre-treatment

Preparing the material

Calcination, roasting and milling to obtain a fine and homogenous ash, ready to be sampled.

We receive materials of any kind in the pre-treatment station, such as for example typical sweepings, borax, crucibles, sludges of goldsmiths’ and silversmiths’ companies, as well as spent catalysts that are thermally treated or milled, or any material which has previously been calcined in the customer’s facilities, that has to be recovered. Metallic waste (mainly from silverware and gold items) is smelted and sampled in a dedicated line, which is located in an armored facility due to the high concentration of precious metals, and it is shipped to undergo recovery through refining.

Eligible materials

Material assessment

We receive several kinds of materials and after conducting numerous inspections during the acceptance of goods, we assess whether there is a need to carry out a preliminary treatment to prepare the material for sampling.

The assessment at this stage helps defining whether the material needs a preliminary treatment before moving on to sampling, and if that’s the case, what is necessary for it to achieve its best and most efficient format in view of the sample collection.

We receive help from the analysis lab that takes part in this procedure, to support manufacturing processes.

Not all materials need to be pretreated; if a material is deemed fit for sampling, we do so in the dedicated facility.

• Calcination (if necessary)

• Milling

• Roasting (if necessary)

The facilities

The pre-treatment facilities are located beside the area dedicated to the receipt of goods, material control and sampling. These facilities can be accessed, in compliance with safety policies, by clients or other individuals monitoring the sampling of the material, such as arbitrators and representatives.

The facilities are big and separated in distinct areas, each one containing the technologies needed for each specific operation, such as static furnaces, mills and mixers, as well as guest areas.

In a control room, located inside the area, expert employees manage through specific software the correct labeling of the goods and collected samples, and monitor the activities throughout the whole process.

Calcination

We own 13 static furnaces where we process each batch separately, obtaining a fine and homogenous ash, ready for sampling.

The type of material determines the time needed for the process and, as a consequence, the effective capacity, compared with a daily nominal capacity of 13 tons: as a matter of fact, calcined material must cool down, before being able to undergo the following treatment.

Operations are carried out in separated lines: the materials of goldsmiths and silversmiths is separated from industrial materials, such as catalysts from the pharmaceutical sector or petrochemical sector.

The trays settings allow each element to be isolated, preventing any potential contamination and it also generates substantial energy savings: as a matter of fact, the flame is positioned at the bottom of the furnace and the process takes place by induction ignition, the natural transfer of heat from one tray to another, triggering a self-ignition process.

This technique allows not only to save energy, but also to avoid turbulences in the combustion chamber, which could waste precious metal.

Eligible materials

Milling

The milling process takes place inside the mills, with the purpose of obtaining a fine and homogeneous ash. The optimal fineness degree for the collection of several samples is 80 mesh.

This parameter is deemed optimal by not only us, but also by our clients, as well as by the world’s most important labs with which we work.