Cast Shop Technology: Melting, Energy, and Dross
Sponsored by: TMS Light Metals Division, TMS: Aluminum Committee
Program Organizers: David Gildemeister, Arconic Technology Center
Tuesday 8:30 AM
February 28, 2017
Location: San Diego Convention Ctr
Session Chair: Cindy Belt, Metals Energy Management, LLC; Mark Jolly, Cranfield University
8:30 AM Introductory Comments
Application and Results of Oxipyr Diluted Combustion in Aluminum Furnaces: Michael Potesser1; Johannes Rauch1; 1Messer Group
Diluted, mild or flameless oxyfuel combustion has shown in the past years huge successes as an optimization tool for different high temperature applications. This innovative combustion technology has a lower flame temperature, more uniform temperature distribution and low concentrations of oxygen as well as nitrogen inside the furnace, leading to low fuel consumption and very low NOx levels. In this work we analyze the optimization processes of different types of rotary and reverberatory furnaces (fix, tiltable) with Messer Oxipyr® burners, which led to impressive savings, dross reduction and ecological improvements for the customers. A review of the available literature, on this topic, is also given.
Case Study of Magnetically-Stirred Casting Furnaces at New Zealand Aluminium Smelters Limited: Ray Cook1; Marcos Varayud1; Steve Iijima2; Eishin Takahashi2; 1New Zealand Aluminium Smelters Limited; 2Zmag, Ltd.
New Zealand Aluminium Smelters Limited (NZAS) supplies the highest purity primary aluminium ingot, high quality extrusion billet and rolling slab products. In 2011 NZAS installed Zmag’s MagStir™ into a 50T casting furnace. MagStir utilizes zPMC™, Zmag Permanent Magnetic Circuit, the world’s first, proprietary permanent magnet-based technology for contactless stirring in the bath. Agitation of casting furnaces during alloying to achieve elemental dissolution and temperature control is the key part of furnace preparation and when performed in an efficient manner, it can give significant savings in fuel and alloying costs and increased throughput. In 2016 NZAS added MagStir to two more casting furnaces and achieved significant improvements in temperature control during all phases of furnace preparation. This paper is a case study on the benefits of stirring in general, specific benefits observed using Zmag's MagStir at NZAS as well as lessons learned in the operation of the systems over 5 years.
Energy Efficiency Status-quo of UK Foundries: The “Small-Is-Beautiful” Project: Mark Jolly1; Konstantinos Salonitis1; Fiona Charnley1; Peter Ball2; Hamid Mehrabi1; Emanuele Pagone1; 1Cranfield University; 2University of York
Energy efficiency is a critical issue for all manufacturing sectors. In the present paper the energy efficiency of UK foundries was assessed. In the context of this research 80 foundries were studied, 60 were contacted and 9 were visited. General energy data were collected using structured questionnaires, interviewing energy managers and process operators. A number of foundries are operating to a good standard, by employing energy managers and regularly auditing, they are in control of their process and working rigorously to improve their efficiency. Simultaneously though, smaller foundries have not adjusted to the new market demands and are operating in not that energy efficient manner. Important barriers to energy efficiency in these foundries include lack of knowledge on auditing methods, poor knowledge in managing energy consumption, the efficiency of individual process steps, production disruptions, aging equipment, personnel behavior, inadequate maintenance and lack of investment, automation and research.
9:55 AM Break
Optimization of Recovery Efficiency for Briquetted Aluminum Chips up to Briquetting Parameters: Ali Ulus1; Hamdi Ekici1; Erdem Güler1; 1Teknik Aluminium
Nowadays, the most important problem is the high cost as casted products. Foundries are increasing the use of secondary sources to reduce their raw material costs. Especially, for continuous caster edge milled swarf has a big potential for possible new secondary source. Usually this swarf has a high amount of oil ingredient and low density and this properties lead this material as a low quality and low recovery rate source. To solve this problem some of the companies try to reduce oil usage, some of them changing the oil type. However especially for reverberatory melting furnaces the density must be higher than molten aluminum density. We will evaluate the chip briquetting solutions to improve melting efficiency for chips. Also we will conducting the density and oil amount results together with edge miller oil usage, swarf oil amount, cyclone filter parameters, pressing parameters, oil reduction methods and melting efficiency of briquetting.
The Evaluation of Hot Dross Processing Systems: David Roth1; 1GPS Global Solutions
On site Hot Dross Processing systems (HDP) offer a method for significant environmental savings with on site aluminum recovery. HDP often can eliminate the remelting of the recovered sows or at worst take advantage of the retained heat in the poured off sow. The most advantageous systems offer productive end use of the dross oxides and aluminum fines left in the residual materials after the aluminum is recovered. All of these systems offer significant environmental advantages over pan cooling or dross pressing of materials that simply change the form of the aluminum and require further off site processing. This paper will review and give analysis of the following systems: 1. Dross Stirrers 2. Dross Stirrers with Coolers 3. On site rotary furnaces 4. On site aluminum separation with oxide processing