11 - 13 von 13 Ergebnissen

Flameless Oxyfuel Combustion for Production and Recycling of Non-Ferrous Metals

10,00
Preis inkl. MwSt., zzgl. Versand


Dr.-Ing. Thomas Niehoff

Oxyfuel flames are known for their bright colour and hot combustion temperatures. The combustion process without nitrogen has an intense and sharp flame. When burning fuel with air the nitrogen content of air (ca. 78 vol.-%) cools and dilutes the flame and combustion reactions. Nitrogen does not take part in the combustion reactions, but enters the combustion as a cold gas and leaves it at higher temperatures. Oxyfuel flames can be above 2300 °C and air fuel flames are typically in the range of 1700 °C (non-adiabatic). The heating and melting of nonferrous metals must be energy efficient and low in emissions. This paper will describe the features of flameless oxyfuel combustion and how they impact the production of non-ferrous metals.

Diese Kategorie durchsuchen: General Hydrometallurgy

FGS – The New Hot Chamber Die Casting

10,00
Preis inkl. MwSt., zzgl. Versand


Dr.-Ing. Norbert Erhard

Die Casting is a technically mature production process to manufacture complex components in large quantities. In the duality for plastic injection molding, it has ever been the ambition in die casting to reduce the casting runners of the mould further or even eliminate them. The specific requirements in non-ferrous metal die casting do not allow transferring the hot runner technologies of plastic injection moulding easily. Only with the development of the Frech Gating System (FGS-System) Frech has succeeded in producing parts with virtually no sprue in hot chamber die casting. In this connection the tempered melt is led to the cavity in the die and the casting process of the cell is modified so that the melt front in the die can always be hold at the outlet point of the heated runner system. Thus the FGS system is not only a hot runner system, but also a special hot chamber die casting process. As an obvious advantage of the FGS system the considerably reduced shot can be recognized as a result of eliminated parts of runners. The lower material capacity and the reduction of recycling portion per shot are the correlated advantages. In addition, there are further benefits, that can be demonstrated in the part quality, the process and energy efficiency. The lecture presents the FGS technology and proves the possibilities, potentials and advantages of the hot chamber die casting on practical examples.

Diese Kategorie durchsuchen: General Hydrometallurgy

Enhanced Smelting Furnace Sustainability Using Non Destructive Testing (NDT) and Monitoring

10,00
Preis inkl. MwSt., zzgl. Versand


David Chataway, Richard MacRosty, Ravi Pula, Afshin Sadri, Wai Lai Ying

The sustainability of a smelting furnace manifests itself through its ability to operate safely and to save resources. These qualities, the safe operation of a furnace and the amount of resources it saves, are primarily influenced by the campaign life length of the furnace and the prevention of run outs and maintenance outages. New developments in non destructive testing (NDT) and monitoring have allowed furnace operational management teams to have a greater understanding of their furnace and process. This has led to longer furnace campaign lives and improved prevention of run outs and furnace maintenance. As a result, smelting furnaces are safer and have lower environmental and economic impacts by reducing the frequency and scale of maintenance and rebuilds. To inspect and monitor smelting furnace integrity, a number of non-destructive testing (NDT) and monitoring techniques have been developed by the Hatch NDT Group. NDT inspections refer to periodic measurement services while NDT monitoring refers to technology which is installed and provides continuous measurements. NDT inspection techniques utilized by smelting furnaces include the patented Acousto Ultrasonic-Echo (AU-E) and Low Frequency Pulsed Ultrasonic (LFPU) techniques. NDT monitoring technologies provided to smelting furnaces include various patented Acoustic Emission (AE), eddy current, radar and fiber optic systems. Each of these technologies and services are designed to deal with unique challenges facing smelting furnaces. One of the main challenges facing smelting furnaces is the refractory wear of the furnace lining. Furnaces are lined by refractory bricks or castables to protect the structure against the harsh operational environment. With time, refractory linings in smelting furnaces undergo deterioration and wear. The deterioration is mainly caused by thermal stresses and chemical attacks, resulting in loss of heattransfer and load-bearing capabilities. Failure of the lining is dangerous and can affect the structuralintegrity of the furnace. Aside from refractory wear, other challenges facing smelting furnaces include wear of the tapblocks and control of the matte, slag and feed/charge levels in the furnace. This paper will discuss the various NDT techniques and how they help solve the challenges presented by smelting furnaces. This paper will show how the NDT inspection and monitoring of a smelting furnace leads to better safety, longer service life of the furnaces, controlled maintenance and increased production.

Diese Kategorie durchsuchen: General Hydrometallurgy
11 - 13 von 13 Ergebnissen