The portable XRF analyzer has a very quick return of investment. A scrap sorter processing more than100 tons/month can potentially earn the investment back in three months. The money comes from the following sources:
- There is a shortage of scrap. The one who pays the best price gets the material (but must know what he is buying).
- Upgrading of scrap: The steel mill pays for the minimum guaranteed concentration. If a stainless steel pile of scrap containing 304 having Ni content between 8- 12% is resorted to two piles, one having 8-10% and the other 10-12% Ni, the last pile is paid for based on 10% Ni, a substantially higher price.
- Certain tramp elements will result in penalties for the seller. These tramp elements can be determined using a portable XRF analyzer.
The value of stainless comes mainly from its approximately 10% Ni content. Mo content of typically 2 % gives extra value. As an example 1 % Ni in stainless steel scrap corresponds to the coverage of a scrap dealer. Scraps other than stainless scrap used in stainless steel production are Cr-steel scrap, Ni-steel scrap, carbon and low alloy steel scrap, Mn-steel scrap and Ni-alloy scrap.
Elements that cannot be reduced in the metallurgical process are P, V, Cu, W, Nb, Co, Sn, Pb and Ta. In addition, C and S cannot be reduced in foundries. All these elements have to be analyzed. Scrap dealers sort scrap using mainly portable XRF analyzers. Scrap is then analyzed again in the steel factory. A typical stainless steel producer does rough sorting with a portable XRF analyzer and analyzes a statistical sample of every load with a big stationary lab analyzer in the lab.
The penalty limits beyond which the scrap price can be decreased for tramp elements in stainless steel scrap are:
| Elements|| Limit|| Elements|| Limit|| Elements|| Limit|
| P|| 0.04%|| W|| 0.1%|| Sn|| 0.03%|
| V|| 0.2%|| Nb|| 0.1%|| Pb|| 0.002%|
| Cu|| 0.5%|| Co|| 0.5%|| Ta|| 0.2%|