Automotive Scrap Recycling

Processes, Prices and Prospects

James. W Sawyer

• Publisher: Routledge
• Year: 2016
• Print ISBN:
  9781138962613
• eBook ISBN:
  9781317333739
• Topic: Biological Sciences
• Subtopic: Ecology
• Index: Biological Sciences

Automotive Scrap Recycling provides a qualitative description of the steel scrap industry by focussing on its largest segment: conversion of obsolete cars into steel scrap. Originally published in1974, this report covers issues such as the structure of the industry and quality problems with scrap steel as well as related policy issues. This title will be of interest to students of Environmental Studies.

1

Ferrous Solid Residuals

TYPES OF RESIDUALS

Society derives rich benefits from the use of ferrous materials. Associated with these social gains, however, are social costs arising from some of the residuals which are waste products of the manufacture, use, and disposal of ferrous materials. Figure 1-1 shows the flow of activities and materials in these processes and emphasizes the various recycling loops and the production of residuals (unpriced waste products) in each step in the sequence.

Some residuals, such as water vapor produced in the combustion of fuel, are harmless. Others, however, impose costs on society in one way or another: sulfur dioxide and other gases which are a by-product of steel production are not only unpleasant but also probably associated with increased morbidity and mortality rates; the particulate matter produced in both steel production and scrap processing operations produces a physically dirty environment, thereby increasing cleaning costs and decreasing property values. It may also be associated with increased morbidity and mortality rates.

The social costs that occur as unwanted side effects of industrial operations are of great importance, for they must be taken into account in determining optimum production levels. This is no easy task when recycling is involved, for, as Spofford¹ points out, the private market system fails to allocate common property resources (air, water, land) efficiently among all users. These are the very resources that are used for disposal of residuals, but at present the cost of disposal is largely borne by the general public in the form of lowered environmental quality. Thus the private market optimum does not necessarily conform to the social optimum.

Some residuals or some portions of residuals have the potential of being recycled at low net cost. An excellent example of such a residual is the particulate matter formed during the production of pig iron in a blast furnace. These particulates are mostly iron oxide. They have a high density, thus allowing for ready separation from the accompanying gas stream. But more importantly, since they contain iron, the collected particulates can serve as one of the feedstocks for the blast furnace. Thus residuals containing a large amount of iron and steel are of particular interest and receive special emphasis in figure 1-1.

There are also residuals that present specific problems because of their location. Abandoned vehicles are examples of this type of residual. Accumulating automobiles, whether scattered at random on the landscape or gathered together in the salvage yard, may impose costs on society in that they may detract from the potential natural beauty of the environment.

Residuals are a normal consequence of the production of steel scrap. The extent of this residual production has never been seriously studied, but it is common knowledge among people familiar with the scrap industry that significant amounts of solid residuals are formed in the dismantling of automobiles and their conversion to processed scrap. For example, the tires are always removed and disposed of in some way. Moreover, the newest and most advanced device for converting a dismantled automobile into usable processed scrap, the shredder, produces large amounts of airborne particulates and solid waste, and requires substantial energy inputs. In addition, the processes that convert steel scrap to useful steel produce residuals also.

RECYCLING VERSUS DISPOSAL

The question of interest here is whether the sum of all the costs, both private and social, associated with the usage of a given quantity of steel is less if the final product is processed to obtain reusable material or less if the steel object is disposed of as solid residuals after its useful life is over. While the answer intuitively seems to be the former, a detailed analysis of the problem is required to assure us that this is indeed correct.

Such a comparative analysis of “total systems” to produce a given final output might result in different answers, depending on circumstances. Consider just one of the many predominantly steel objects currently in use, the office safe. Scrap dealers refuse to purchase safes, or even to accept them at no charge, because an office safe is usually made of a sandwich of steel and concrete. This design makes the recovery of steel so costly as to be unprofitable. This suggests that whether or not an object should be recycled will depend on the total inputs necessary for utilizing the residual as a source of raw material. The same problem exists with respect to the total inputs necessary to use “virgin” raw materials, that is, iron ore.

FIGURE 1-1. The steel supply system.

A second example furnishes yet another perspective on the problem. If an automobile ends its useful life near a large city with a demand for steel scrap, such as Philadelphia, there will be: (a) large numbers of other automobiles in the immediate vicinity, many of which will also be ending their useful life; and (b) low transportation costs associated with collecting the obsolete automobiles, transporting them to a processing center, and then taking the processed material to a scrap consumer. By contrast, automobiles ending their useful life in rural New Mexico are few in number and widely scattered. This makes them costly to collect and transport to the nearest scrap processing center, Albuquerque. In addition, while there is a market for scrap within a few miles of Philadelphia, the steel scrap market nearest to Albuquerque is El Paso, Texas, some 250 miles away. Therefore, the scrap product transportation costs are high. Thus it would be less than surprising if a detailed analysis of the steel scrap problem showed that the answer to the question of whether the benefits of recycling exceed the costs depends, not only on the characteristics of the used steel object under consideration (as in the case of the office safe), but also on its location at the end of its useful life (as in the case of the automobile in the New Mexico countryside).

TYPES OF SCRAP

This study is concerned with what is usually termed “obsolete” scrap, or sometimes “post-consumer” scrap, as opposed to “home” scrap and “prompt” scrap, because it is post-consumer scrap that is of most concern to society. Home scrap refers to the steel scrap that is an unavoidable nonproduct output of the steelmaking operation. For example, in the production of steel sheet, the rough edges of the sheet must be trimmed; this trim is immediately recycled in the mill to produce more steel. Prompt scrap refers to the steel that is a nonproduct output of steel fabricating operations. For example, in the fabrication of an automobile fender from steel sheet, the excess material must be trimmed off, and this trim is transported back to the steel mill for recycling to produce more steel. It is relatively easy for steel companies to recycle home and prompt scrap at a profit, since their metal content is known and large quantities are generated in a single location. As a result, home and prompt scrap impose small social costs (externalities) on society. Post-consumer, or obsolete, scrap often imposes serious costs on society, hence it should receive the most careful scrutiny. Figure 1-2 clarifies the nomenclature employed for home, prompt, and obsolete scrap.

The value of scrap, as with any raw material, is most affected by its location, quantity, and quality. As Bower² points out, in processing residuals, it is most desirable to have a large mass of high-quality material close to the source of production or market. The relevance of these points to ferrous scrap consumption is amply demonstrated by an examination of the relative magnitude of scrap flows, by source, in the ferrous materials industry. Two studies by Battelle Memorial Institute, one in 1957³ and one in 1972,⁴ have furnished sufficient information to allow an approximate calculation of usage of scrap, by source, in the ferrous materials industry. The Commerce Department has used the information obtained by Battelle in the 1955 study to calculate scrap flows, by source, as a percentage of total scrap flows, and has also supplied information on the total amount of scrap going to the ferrous materials industry, expressed as a percent by weight of the total metallic feed.⁵

Data calculated from the Commerce Department study (Business and Defense Services Administration—otherwise known as BDSA) are shown in figure 1-3 and in table 1-1 for the period 1947 through 1964. The data make it clear that (a) total scrap feed is more or less constant at about 50 percent by weight of total metallic feed; (b) home scrap and purchased scrap—which together constitute total scrap—are about 30 percent and 18 percent respectively of total metallic feed; (c) the home scrap portion of total metallic feed is increasing, the purchased scrap decreasing; (d) prompt scrap and obsolete scrap—which together constitute purchased scrap—are about 18 percent of the total metallic feed, with prompt scrap retaining a more or less constant percentage of the total, and obsolete being used at a lower rate at the end of the period than at the beginning (expressed as a percentage of total metallic feed); (e) in the 1960–1964 period, obsolete scrap constituted 10–12 percent by weight of the total metallic feed to the ferrous materials industry.

FIGURE 1-2. Simplified flow diagram of steel supply system showing the major recycle loops.

FIGURE 1-3. Scrap as a weight percentage of total metallic feed to ferrous materials industry broken down by scrap source. Department of Commerce estimate (see note 5).

In 1972 Battelle completed a second major study of the steel scrap industry and in light of their new findings reported that obsolete scrap as a percentage of total purchased scrap was probably on the order of 40 percent of total pu...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Original Copyright Page
• Table of Contents
• ACKNOWLEDGMENTS
• INTRODUCTION
• Chapter 1. FERROUS SOLID RESIDUALS
• Chapter 2. A QUALITATIVE INTRODUCTION TO THE FERROUS SCRAP INDUSTRY
• Chapter 3. PROCESSED FERROUS SCRAP GRADES AND STEEL SCRAP QUALITY
• Chapter 4. THE SUPPLY OF DEREGISTERED AUTOMOBILES AND HULKS
• Chapter 5. THE DISMANTLING MODEL
• Chapter 6. HULK TRANSPORTATION AND PROCESSING
• Chapter 7. ANALYSIS AND SYNTHESIS
• Chapter 8. PERSPECTIVE
• INDEX