Indutec ezinex integrate process on secondary zinc. The major component of the waelz process is the waelz kiln. Currently isfahan is operating 4 waelz kilns each processing up to 500 tons per. An overview on the influences of physical, chemical and. Engitec also studied the indutec process, a pyrotechnology competitive to the waelz kiln. In the waelz process, dust is treated in a rotary kiln where it is heated to approximately 1,200 c. It pays significant attention to hardware equipment of the waelz process and lining of the waelz kiln. The waelz process is applied on industrial scale in the metallurgy of zinc and it is designed to the enrichment of materials with low metal content to produce a concentrated zinc oxide waelz. Steelworks residues and the waelz kiln treatment of electric arc. For questions or problems with your specific application please contact north american kiln for assistance.
Scheme of a waelz kiln for zinc recycling with sdhlprocess air lance and infrared camera for slag temperature. It gives thermal balance of the waelz kiln and analyses possible breeches of the operating practices. Pdf identification and control of the waelz process using infrared. Informatics in control, automation and robotics, pp. The zinc enriched product is referred to as waelz oxide, and the reduced zinc by product as waelz slag. Camera based identification and control of the waelz process. The waelz process is a method of recovering zinc and other relatively low boiling point metals from metallurgical waste typically eaf flue dust and other recycled materials using a rotary kiln waelz kiln. During eaf operation, electricarc furnace dust, eafd, is generated as a result of.
Beginning with primitive firing methods, rhodes moves on to the evolution of kilns in china, korea, and japan, and then discusses the history and growth of europeans kilns. The furnace can treat various zinc material such as low grade zinc oxide ore, zinc leaching residue, zincbearing water quenched slag from lead smelting, zinc electrolyte purification precipitate. The waelz process is a method of recovering zinc and other relatively low boiling point metals from metallurgical waste and other recycled materials using a rotary kiln. Despite research into multiple alternative technologies, the traditional waelz kiln is the most economically viable processing method for. Olsens bible for kiln builders now includes chapters on multidirectional and specialty kilns, and offers a few suggestions on what kilns may look like in the future. A german invention first put in use in 1925, the waelz kiln is a long and narrow, slowly rotating refractorylined continuous kiln see figure 2. The book is intended for scientists, engineers and technicians who deal with.
The waelz process is applied on industrial scale in the metallurgy of zinc and it is designed to the enrichment of materials with low metal content to produce a concentrated zinc oxide waelz oxide. Regardless of rotary kiln size or configuration the basic principles outlined in this manual govern the reliable operation of every rotary kiln, calciner, dryer, incinerator, digester and cooler application. It is operated counter currently at a rotational speed of. The technology employed at chicago and rockwood is the waelz kiln technology. Rotary kilns transport phenomena and transport processes. See what the career and earning prospects are to decide if.
Mar 29, 2019 learn what a kiln operator does and whats required to become one. This monograph sets forth physicochemical characterization of the waelz process and behaviour of various compounds of lead, zinc, cadmium, indium and others in the waelz processing. After 1 year of operation, an industrial plant producing 2000 ty of zinc cathode was designed. This plant recycles electric arc furnace eaf steel dust utilizing the waelz kiln technology. The rockwood facility has an annual waste processing capacity of 90,000 tons and the chicago plant will bring another kiln online early in 1994, boosting itos capacity to 180,000 tonsyr. The kiln book covers the principles of efficient design, building methods, refractory, materials, bricklaying procedures and instructions, fuels and firing systems, arches, flues, electric elements and general safety. The recovery of zinc oxide from low grade zincbearing material by waelz kiln is a popular and economic method. The first section of the book traces the development of individual kilns, stressing their firing principles and their strengths and weaknesses. Zinc ore and a reductant often a form of coal are introduced into the kiln under flame to initiate the reaction.1277 917 569 365 1370 1348 302 1553 822 70 113 1058 241 1467 1170 746 966 34 80 293 1056 94 1181 1348 331 400 293 787 885 1426 1099 1215 199 198 1139 886