1、1 I Guidelines for Aluminum Inspection Based on Safety -I ,e and Health Considerations 1 Scrap Receiving and *IC Second Edition The Incorporated Aluminum Association o GUIDELINES FOR ALUMINUM SCRAP RECEIVING AND INSPECTION BASED ON SAFETY AND HEALTH CONSIDERATIONS Second Edition These Guidelines hav
2、e been developed by the Aluminum Associations Task Force on Scrap Charging with review and comment by the Institute of Scrap Recycling Industries (ISRI). The Guidelines are based on information believed to be reliable and are offered in good faith but without any guarantee. The conditions which exis
3、t in individual plants vary widely, and thus no uniformly applicable standards exist for handling scrap aluminum. Accordingly, the Aluminum Association and its member companies assume no responsibility or liability for the general applicability of the guidelines and recommendations herein, which tho
4、ugh based on state-of-the-art knowledge may not be appropriate in all situations. Users of these Guidelines should adapt the recommendations herein, as appropriate, to the precise conditions of the individual facility and should always exercise independent discretion in establishing plant or facilit
5、y operating practices. No warranty, expressed or implied, is made of this information by the Aluminum Association or by any of its member companies. CONTRIBUTORS: R. B. Dunsmoor S. G. Epstein O. E. Fornasier R. F. Hubbard C. Johnson C. B. Kahler D. B. Luma C. J. Meyer D. C. Pierce J. D. Schlafmann P
6、. D. Thomas G. A. Tucci D. Smith Copyright O 2002, The Aluminum Association TABLE OF CONTENTS Page i. Introduction 1 A. Purpose of these Guidelines B. Scope C. Overview II. Safety-related scrap specifications and purchase orders . 4 A. Aluminum scrap purchase specifications B. Aluminum scrap purchas
7、e orders C. Scrap shipment documentation III. Scrap-related health and safety hazards . 6 A. Nitrates, sulfates, oxidizers, fertilizers, and unknown powders or residues B. Water, snow or ice entrapped in scrap, sows or pigs C. Volatile substances D. Closed containers, crimped tubing, aerosol cans, a
8、utomobile air bag inflation E. Aluminum “fines” F. Heavily oxidized metals G. Oil, grease or other hydrocarbons H. PCBs, PCB-contaminated oils, or other toxic materials I. Radioactive materials J. Aluminum-lithium alloys K. Unbalanced or improperly loaded or transported scrap L. Hypodermic needles,
9、medical wastes and other hazardous objects cartridges, ammunition cartridges or detonators and similar objects IV. Preparedness for scrap receiving and inspection 10 A. Scrap testing and screening equipment and facilities B. Tagging and isolation of suspect materials C. Contamination-recognition aid
10、s D. Forms and practices V. Contaminated-scrap procedures: general guidelines . 13 A. If powder or radioactivity is found in scrap B. If excess water or other unacceptable contaminants are found or suspected in scrap VI. Preliminary inspections before unloading scrap . 15 A. External vehicle inspect
11、ion before unloading scrap B. Inspection inside the vehicle before unloading VII. Scrap inspection during and after unloading 16 A. Sampling, testing and recording results B. Visual inspections C. Reinspection of the interior of delivery vehicle after unloading D. Scrap storage, in-plant transport,
12、preparation and drying VIII. Aluminum Association Molten Metal Incident Reporting System 26 A. The Incident Reporting System B. Participation C. Reporting Form IX. Aluminum Association Scrap Rejection Notification Reporting System . 28 A. The Scrap Rejection Notification Reporting System B. Particip
13、ation C. Reporting Form D. Summary of reports Received X. References 3 1 I. INTRODUCTION A. Purpose of these Guidelines These Guidelines have been prepared and published with the aim of helping aluminum scrap remelters prevent accident and injury due to moisture and contamination in scrap, and of pr
14、omoting the cooperation and understanding of all scrap suppliers, transporters and handlers in preventing such incidents. Incidents have been reported of explosions caused by contamination from fertilizer or water being charged into a furnace. Eruptions of molten metal from melting furnaces have bee
15、n caused by containers of water being charged. The Aluminum Association recognizes that different scrap remelters may have different facilities, equipment and procedures and may, therefore, adopt a variety of safety practices appropriate to their individual circumstances. In presenting these Guideli
16、nes, the Association does not either suggest or intend that all aluminum scrap remelters should adopt and follow them completely and without deviation. Some plants may find some of these Guidelines inapplicable to their operations; others may adopt alternative or different safety practices not menti
17、oned here in response to their individual circumstances. These Guidelines are entirely safety-related and are not intended to provide commercial advice or guidance of any kind. The Guidelines, then, offer information and suggestions derived from general industry experience for the consideration of i
18、ndividual plants in designing and operating their own scrap-remelting safety programs. All remelting plant and other scrap-handling personnel are expected to follow the safety- and health-related procedures established by their own plant managements. These Guidelines are not intended to pre-empt or
19、replace those procedures. B. Scope Solid bulk aluminum is a very safe noncombustible metal, but molten aluminum and aluminum powder can be highly reactive - capable of releasing large amounts of energy in chemical reactions. Water, nitrates and other oxidizers can cause devastating explosions if cha
20、rged into a furnace that already holds molten aluminum. Various heavily oxidized metals can combine with molten aluminum in a potentially serious thermite reaction; flammable materials can catch fire. Radioactive materials, PCBs and certain other toxic substances can endanger the health of both scra
21、pyard and remelting plant workers. Aluminum “fines” - granulated or powdered aluminum - can explode if mixed with air in the presence of an ignition source. Even live ammunition has been discovered in aluminum scrap! 1 General safety practices are discussed in the Aluminum Associations Guidelines fo
22、r Handling Molten Aluminum, Third Edition, but hazards of the sort described above must be prevented before aluminum scrap reaches the remelting furnace. Consequently, the following guidelines deal with practices intended to keep water and other contaminants out of aluminum scrap destined for remelt
23、ing; to discover water and contaminants in incoming aluminum scrap; to remove water and contaminants from incoming scrap when possible; and to reject and report unacceptably contaminated scrap. C. Overview Section II begins the Guidelines themselves by discussing safety-related aspects of aluminum s
24、crap purchase orders and specifications. Clear, comprehensive purchase orders and specifications help to avoid confusion, to discourage the delivery of scrap containing unacceptable contamination, and to make inspection more effective. Section III identifies the major types of contamination which ma
25、y be found in aluminum scrap and outlines the hazards each of them presents to human health and safety. Section IV discusses preparedness: some types of equipment, facilities, procedures and aids which may enhance the effectiveness of scrap reception, inspection and handling from the safety standpoi
26、nt. Section V suggests general guidelines for dealing with scrap found or suspected to contain dangerous or unknown powders, radioactivity, excessive water or other unacceptable safety- related contaminants. Section VI suggests guidelines for safety-related inspections which may be performed before
27、incoming scrap is unloaded. Section VI1 discusses a more complete range of safety-related scrap testing and visual inspections which can be performed during and after unloading. It notes the importance of breaking open bales and other scrap assemblages for internal inspection. It also suggests a fin
28、al inspection inside the cargo area of the delivery vehicle after the scrap has been unloaded, as an additional check for signs of contamination. Certain types of scrap contamination - particularly nitrates and fertilizers containing nitrates, phosphates, and other oxidizing agents - cannot be charg
29、ed safely into furnaces containing molten aluminum, and cannot be reliably removed from scrap. We are not aware of any method for safe use of suchscrap in an aluminum remelting plant. Other types of contaminated scrap may also be rejected by remelting plants, depending upon each plants capabilities
30、and procedures. 2 Section VI11 describes the Aluminum Associations Molten Metal Incident Reporting Program in which reports of incidents worldwide are collected and analyzed, with reports and timely alerts issued to the participants. It is open to all molten aluminum handlers. This cooperative repor
31、ting system helps companies identify causes and patterns of incidents and, as a result, improve their safety practices. Section IX describes The Aluminum Associations Scrap Rejection Notification Program in which loads of scrap rejected for reasons of safety or health are reported to the Association
32、 by telefax. The reports are quickly reviewed and transmitted to all participating plants to apprise them of a rejected load and the reason for rejection. Finally, Section X refers the reader to other publications for additional information related to safety and health aspects of aluminum scrap reme
33、lting. 3 II. SAFETY-RELATED SCRAP SPECIFICATIONS AND PURCHASE ORDERS A. Aluminum scrap purchase specifications In order to minimize scrap contamination problems it is often helpful for aluminum scrap purchasing specifications to clearly define: 1. Acceptable scrap description which is understood by
34、both buyer and seller. 2. Unacceptable or restricted scrap contents, which, for example, may include but are not limited to: a. Fertilizers and other materials containing nitrates, sulfates or other oxidizing agents; salt fluxes contaminated with nitrates, sulfates or oxidizers; and any unknown powd
35、er. b. Water, snow or ice in excess of plant processing capabilities. c. Volatile substances in excess of plant processing capabilities. d. Closed containers, crimped tubing, aerosol cans, automobile air bag inflation cartridges, ammunition cartridges, fire extinguishers, freon tanks, oxygen and ace
36、tylene cylinders, detonators and similar objects. e. Aluminum fines in excess of plant processing capabilities. f. Heavily oxidized metal in excess of plant treatment capabilities. g. Hydrocarbons (e.g. oil, flammable liquids) in excess of plant processing capabilities. h. PCBs or other toxic materi
37、als at levels which constitute or create a health hazard. i. Radioactive materials. j. Aluminum-lithium alloys unless specified. NOTE: Certain forms of aluminum scrap, such as borings, turnings, saw chips, fines, pit cleanings, etc., which contain oil and water, should not be mixed with other scrap
38、unless specified. Extreme care must be taken in processing these forms of scrap. 4 B. Aluminum scrap purchase orders Should: 1. Specify acceptable packaging, container and transport vehicle. 2. Specify required protection against moisture and other contamination. 3. Define required scrap specificati
39、ons using industry standard nomenclature and terminology. 4. Specify required insurance coverage. C. Scrap shipment documentation Should include: 1. Scrap purchase order and specifications. 2. Scrap identification tagging. 3. Bill of Lading. 4. Manifest. 5. Up-to-date Material Safety Data Sheet (MSD
40、S) if not previously provided. 5 111. SCRAP-RELATED HEALTH AND SAFETY HAZARDS Water, nitrates and a wide variety of other materials and objects have the potential to cause explosions, fires and other serious threats to life, health and property, if they are carried by scrap into molten aluminum. Car
41、eful scrap inspection, storage and, where appropriate, preparation, are vital to prevent molten metal incidents and other mishaps. A number of the most significant types of aluminum scrap contamination are listed here with brief descriptions of the hazards they pose if charged into molten aluminum:
42、A. Nitrates, sulfates, oxidizers, fertilizers, and unknown powders or residues Explosion hazard; risk of burns, physical injury, death, severe property damage. These are probably the most hazardous contaminants which can be put into a furnace. Even the small amount of powder residue that may remain
43、after washing may be enough to cause an explosion. Also, salt fluxes which should in principle be harmless may be difficult to distinguish from nitrates, sulfates and oxidizers, and may have become contaminated with them. Therefore, they should be treated like any unknown powder, unless known to be
44、safe. B. Water, snow or ice entrapped in scrap, sows or pigs Explosion hazard ranging from “pops” to major explosions; risk of burns, physical injury, death, severe property damage. Aluminum sows or pigs may contain hidden water in internal cavities. C. Volatile substances Potential explosion and fi
45、re hazards; risk of burns, physical injury, potential exposure to toxic fumes, death, severe property damage. Volatile substances are those which vaporize readily at ordinary temperatures. The most common volatiles are oils and other liquids. The hazard posed specifically by volatiles is that they m
46、ay vaporize and expand forcefully if immersed in molten metal, causing a non-chemical “explosion” which may splash molten metal out of the furnace and possibly trigger a chemical explosion if the volatiles are flammable andor an aluminum mist is created. 6 D. Closed containers, crimped tubing, aeros
47、ol cans, automobile air bag inflation cartridges, ammunition cartridges or detonators and similar objects Explosion hazard, potential exposure to toxic fumes; risk of burns, physical injury, health effects, death, severe property damage. Closed containers, crimped tubing, beverage cans or bottles, r
48、adiators, heat exchangers and other “traps” in scrap may conceal hazardous amounts of water or other volatile liquids capable of causing explosions. Containers may also hold flammable or toxic materials. Live ammunition and explosive detonators have occasionally been discovered in aluminum scrap, po
49、sing obvious hazards to all scrap workers who handle it. Aerosol cans, fire extinguishers, automobile air bag inflation cartridges and similar closed containers may contain gases or chemicals capable of explosive expansion in the heat of a molten aluminum bath. Even if chemical explosion is not likely, such gas-expansion explosions can splash molten metal out of a furnace, threatening nearby workers. E. Aluminum “fines” Aluminum-powder explosion hazard; risk of burns, physical injury, death, severe property damage. While bulk aluminum is non-combustible, finely divided aluminum can burn
