Servosteel

[Tristan_Parker]

Servosteel is the UK’s largest steel toll processor, offering a range of specialist services for the steel industry, including ‘SCS’ (a steel cleaning process), coil pickling, slitting and decoiling.

The company has made a recent investment of over £3 million in a new steel coil processing machine called SCS: Smooth Clean Surface. This process has been carbon indexed and found to produce 87% less carbon dioxide compared to the industry standard method.

The process uses 3M closed cell brushes to mechanically brush the surface of steel coils and remove scale and corrosion, while the machine itself has built-in high torque tension levellers which can be used with or without surface cleaning, meaning that SCS can remove shape from steel coils and consistently produce exceptionally flat coils with an extremely clean surface, which resists corrosion for longer periods of time in normal storage conditions. A small amount of water is used to cool and lubricate the rolls as well as wash away the iron oxide which has been removed, and the machine can also be used to reclaim damaged or degraded steel coils and restore them to prime condition.

With the help of Business Link and Pro Enviro Ltd, Servosteel has carbon indexed the SCS process and compared it with the traditional acid pickling of steel coils, known as Pickling and Oiling (P&O). The ‘Carbon Index’ is a method used to compare and display the equivalent carbon dioxide produced by a process. Typically, this method calculates a baseline year as 100%, before data is collected one year in the future and displayed again to demonstrate a change in the equivalent carbon dioxide produced by a process. In the case of Servosteel’s SCS process, the P&O process index is calculated and taken as 100% and then the SCS index is calculated and displayed as a simple proportion of the P&O index.

Through this methodology, it was independently determined that SCS material has a significantly lower environmental impact than pickled and oiled steel, established through measured consumption of five different resources: gas; electricity; water; hydrochloric acid, and mineral oil. The recorded data demonstrate that 108.4 tonnes of steel processed by the SCS method (a figure for a typical processing day) used 598 kWh of electricity, using standard conversion factors this produces 325 kg of equivalent carbon dioxide, meaning that the SCS process produces 3 kg of equivalent carbon dioxide per ton of steel processed.

When the same calculations were applied to the P&O process, it was found that this method produces 22.4 kg of equivalent carbon dioxide per ton of steel processed. Therefore, the SCS process emits 87% less carbon dioxide for every tonne of steel processed compared to the widely used P&O method.

A Servosteel report on the comparison summarised the results and the implications for carbon savings from steel processing as follows: “The difference between the two processes is very significant. For example, for a steel coil toll facility processing 200,000 tons of coils per annum, a switch from traditional P&O to the SCS process would reduce emissions by CO2e [equivalent carbon dioxide] = 3,880 t/annum.”

Servosteel is also enabling companies that specify SCS material from their supplier – instead of the traditional P&O material – to get an exact carbon emissions saving figure from them, which can then be incorporated into further carbon dioxide saving calculations.

In addition to reducing carbon, SCS also has other environmental benefits: as the machine uses no acids, there is no waste landfill produced. Also, as only a small amount of water is used in the process, it is easy for this water to be constantly recycled, through a three-stage filtration system. This means that the machine not only has no water consumption, but also causes no water contamination.