Aluminum Recycling, 2nd Edition

45

4

Aluminum Recycling

Economics

Although public support for recycling as a means of achieving social goals is wide-

spread, in the end recycling is not a religious activity. It is not carried out by people

who are trying to save the planet. Recycling is carried out by people and organiza-

tions who are trying to earn a prot. They face competition from other recyclers and

from producers of primary material and do not control the price of their product.

Their success depends on their ability to purchase raw materials at the lowest pos-

sible price and process them at the lowest possible cost. As a result, the economics

of recycling is an important part of the secondary aluminum story and one that is

critical to understanding the choices of processing strategy described in the next

few chapters. The discussion will include both the cost of what recyclers use and the

value of what they produce.

SCRAP GRADES

Figure 4.1 lists the grades and specications of aluminum-containing scrap com-

piled by the US Institute for Scrap Recycling Industries (ISRI, 2012). Different

scrap grades have different values; a comparison of some of these grades will

explain why.

The rst two grades in Figure 4.1, Tablet and Tabloid, are largely identical.

However, Tabloid is new scrap, free of ink and paint. Tablet is old scrap and thus has

ink and possibly paint on it. As a result, Tabloid will have greater value than Tablet.

Several other types of scrap have separate grades for new and old material; the new

material is always worth more.

Taboo is a common grade of aluminum scrap (Figure 4.2). Its specication

demands little or no alloyed copper. This increases the possibility of using it to pro-

duce wrought alloys when it is remelted. The tolerance problem was discussed in

Chapter 2; the low-copper specication is a result of this. Taboo also has limita-

tions on smaller-sized materials and the amount of oil and grease it can contain.

Smaller scrap pieces are more likely to oxidize when put in a melting furnace, lower-

ing overall yields and generating more dross. Excessive grease will generate smoke

and soot during the melting process, damaging the workplace environment. A plant

that only purchases oil-free scrap can avoid having to purchase a decoating furnace

(see Chapter 5). Limitations of these types are common through the descriptions in

Figure 4.1.

There are six types of UBC scrap—Take, Talc, Talcred, Taldack, Taldon, and

Taldork. Take is new scrap (Figure 4.3); the others are old. Talc and Talcred are loose

scrap; the others have been densied by briquetting, bundling, or baling. Densied