IRONMAKING AND STEELMAKING
Since the early ‘80s Danieli has been one of the leaders in secondary refining for ordinary, specialty and stainless steels. The know-how gained over many years has been used to develop and optimize equipment and processes, and also to meet our customers’ most stringent requirements.
The Ruhrstahl-Heraeus (RH) process, also called Vacuum Circulation Process, is the vacuum process commonly used in integrated steel plants. It was developed in response to BOF steel plants' need to treat large ladles for short cycle times.
The initial idea, more than 50 years ago, was to have a vacuum treatment method to produce large vacuum-treated ingots. In the caming years, the targets will be to increase plant availability and treatment time (e.g., fast vessel exchange and twin-station design, or a combination of both) as well as to reduce fuel consumption.
Currently, waiting times for vacuum pump operation and maintenance activities can be optimized or eliminated with the installation of a second treatment station. A twin station installation consists of two treatment positions that can be connected to a common vacuum pump by a moveable elbow.
The vacuum system my include a steam ejector vacuum pump designed with successive compression of process gas and steam with intermediate steam condensation (inter-condenser), or a dry mechanical multi-stage vacuum pump with several parallel skids / modules.