Steel Takes LEED with Recycled Content

Designers and builders have long recognized

and lauded steel for its strength, durability, and

functionality. Increasingly, however, architects are

recognizing steel’s important environmental attributes—

especially its high recycled content and high reclamation rate.

For many years, there has been a strong economic

motive to incorporate recycling into the

process for making steel, but today's environmental

concerns make recycling even more important.

Recycling saves money while conserving energy

and resources, as well as reducing solid, liquid,

and gaseous wastes. Recycling also helps to

spread the energy impact of the original extraction

and manufacturing of the material over infinite generations

of new steel.

The efficiency with which a material is recycled

can be measured by either its percentage of recycled

content or its reclamation rate. Recycled content

is a measure of how much recycled material is

contained in a finished product. The reclamation

rate is a measure of how often a product is actually

recycled at the end of its useful life. Steel is an

exceptional performer by both measurements. In

the construction industry, recent interest in recycling

has been driven largely by the US Green

Building Council's Leadership in Energy and

Environmental Design (LEEDTM) rating system. The

LEED rating system only promotes the use of

materials with high levels of recycled content. The

equally important reclamation rate of the materials

is not currently considered.

Scrap consumption in the United States is maximized

between the two types of modern steel mills,

each of which generates products with varying levels

of recycled content. One type of mill produces

much of the steel for light flat-rolled steel products

with about 30% recycled content. The other type of

mill makes steel for a wide range of products,

including flat-rolled, but is the only method used

domestically for the production of structural

shapes and has about 95% recycled content.

(These processes are covered in detail on the following

pages.)

The amount of recycled content in steel products

varies over time, both as a function of the cost of

steel scrap and its availability. As the world-wide

demand for steel increases, the available scrap will

be stretched between more and more steel products,

meaning that more raw steel will have to

enter the production stream to meet the demand.

Fortunately, steel is the country's most widely recycled

material, and as more steel is used for construction

and other products, more scrap is available

for future recycling. About 88% of all steel

products and nearly 100% of steel that is used in

beams and plates in construction, are recycled into

new steel products at the end of their useful life—

an amazing reclamation rate!

In addition to recycled content, steel can contribute

toward several other LEED credits, either

directly or indirectly. Steel is dimensionally stable

and, when properly designed, can provide an

exceptionally tight building envelope, for less air

loss and better HVAC performance over time.

Steel is made to exact specifications, so on-site

waste is minimized. Material from demolition or

construction can be easily recycled, with the magnetic

properties of steel greatly facilitating its separation

from other materials. Thus, in addition to

steel's outstanding recycled content and an enviable

reclamation rate, steel's other functional properties

contribute to the material's solid environmental

performance.

As with any building process or material, there

are areas for improvement. A great benefit of

LEED is that it can help the steel industry recover

even more scrap as contractors improve their recycling

collection methods at the job site, so less incidental

iron and steel scrap escapes to landfills.

Similarly, commercial buildings and residential

housing can have better disciplined recycling systems

for increased recovery.

As steel products reach the end of their useful

life, we want to see even more recycled into new

steel products for future service to society.

America’s—most recycled material. In the United

States alone, almost 69 million tons of steel were

recycled or exported for recycling in 2003. Modern

steel production relies on two technologies, both of

which utlize old steel to make new steel: the basic

oxygen furnace (BOF) and the electric arc furnace

(EAF).

➮The basic oxygen furnace (BOF) process

uses 25 to 35 percent old steel to make

new. It produces products—such as automotive

fenders, encasements of refrigerators,

and packaging like soup cans, five-gallon

pails, and 55-gallon drums—whose

major required characteristic is drawability.

➮The electric arc furnace (EAF) process

uses 95-100 percent old steel to make new.

It is primarily used to manufacture products—

such as structural beams, steel

plates, and reinforcement bars—whose

major required characteristic is strength.

Steel recycling has both an economic and environmental

benefit: It is less expensive to recycle

steel than to mine virgin ore and move it through

the process of making new steel. And today two

out of every three pounds of new steel are produced

from old steel. However, because steel is

such a durable material (that is, cars, appliances,

bridges and other steel products last a long time),

it is necessary to continue to mine virgin ore to

supplement the production of new steel. Economic

expansion, domestically and internationally, creates

additional demand that cannot be fully met by

available scrap supplies.

Unlike other competing industries, recycling is

second nature for the steel industry. The North

American steel industry has been recycling steel

scrap for over 150 years through the 1,800 scrap

processors and some 12,000 auto dismantlers.

Many of them have been in the business for more

than 100 years.

The pre-consumer, post-industrial, post-consumer,

and total recycled content of steel products

in the United States can be determined for the calendar

year 2003 using information from the

American Iron and Steel Institute (AISI), the

Institute of Scrap Recycling Industries (ISRI), and

the U.S. Geological Survey. Additionally, a study

prepared for the AISI by William T. Hogan, S.A.,

and Frank T. Koelble of Fordham University is used

to establish pre- and post-consumer fractions of

purchased scrap. (Detailed information on these

studies can be obtained from the Steel Recycling

Institute (call 412.922.2772 or visit www.recyclesteel.

org.)

Individual company statistics are usually not

applicable or instructive since available scrap typically

goes to the closes melting furnace. This open

loop recycling allows, for example, an old car to be

melted down to produce a new soup can, and

then, as the new soup can is recycled, it is melted

down to produce a new car, appliance, or structural

beam.

Basic Oxygen Furnace

BOF facilities consumed a total of 15,772,900

tons of ferrous scrap in the production of

50,941,700 tons of liquid steel during 2003. Based

on U.S. Geological Survey statistics, 1,738,800 of

these ferrous scrap tons had been generated as

unsalable steel product within the confines of

these steelmaking sites. In the steel industry, these

tons are classified as "home scrap," but are a mix

of pre-consumer scrap and post-industrial scrap.

Estimates by the Steel Recycling Institute identify

about 80% of this home scrap as post-industrial

scrap, equating to 1,391,000 tons (1,738,800 x

80%). Additionally, these operations reported that

they consumed 148,800 tons of obsolete scrap

(buildings and warehouses dismantled on-site at

the mill) during this time frame. This volume is classified

as post-consumer scrap.

As a result of the above, based on the total scrap

consumed, outside purchases of scrap equate to

13,885,300 tons [15,772,900 - (1,738,800 +

148,800)]. According to the Fordham University

study, the post-consumer fraction of the purchased

ferrous scrap would be 83.4 percent, while 16.6

percent of these purchases would be pre-consumer.

This equates to 2,305,000 tons of pre-consumer

scrap (13,885,300 x 16.6%). This "prompt

scrap" is mainly scrap generated by manufacturing

processes for products made with steel. It is also

considered post-industrial scrap.

Therefore, thetotal recycled contentto produce

the 50,941,700 tons of liquid steel in the BOF

is:

15,772,900 / 50,941,700 = 31.0%

(Total Tons Ferrous Scrap / Total Tons Liquid Steel)

Also, thepost-consumer recycled contentis

(13,885,300 - 2,305,000) + 148,800 = 11,729,100

and:

11,729,100 / 50,941,700 = 23.0%

(Post-Consumer Scrap / Total Tons Liquid Steel)

Finally, thepost-industrial recycled contentis

(1,391,000 + 2,305,000) / 50,941,700 and:

3,696,000/ 50,941,700 = 7.3%

(Post-Industrial Scrap / Total Tons Liquid Steel)

Electric Arc Furnace

EAF facilities consumed a total of 44,661,700

tons of ferrous scrap in the production of

46,310,300 tons of liquid steel during 2003. Based

on U.S. Geological Survey adjusted statistics,

12,124,000 of these ferrous scrap tons had been

generated as unsalable steel product within the

confines of these steelmaking sites. Again, in the

steel industry, these tons are classified as "home

scrap," but are a mix of pre-consumer scrap and

post-industrial scrap. Estimates by the Steel

Recycling Institute identify about 80% of this home

scrap as post-industrial scrap, equating to

9,699,200 tons (12,124,000 x 80%). Additionally,

these operations reported that they consumed

28,700 tons of obsolete scrap (buildings and warehouses

dismantled on-site at the mill) during this

time frame. This volume is classified as post-consumer

scrap.

As a result , based on the total scrap consumed,

outside purchases of scrap equate to 32,509,000

tons [44,661,700 - (12,124,000 + 28,700)].

According to the Fordham University study, the

post-consumer fraction of the purchased ferrous

scrap would be 83.4 percent, while 16.6 percent of

these purchases would be pre-consumer.

This equates to 5,396,500 tons of pre-consumer

scrap (32,509,000 x 16.6%). This "prompt scrap" is

mainly scrap generated by manufacturing processes

for products made with steel. It is also considered

<SPAN style="FONT-SIZE: 10pt; COLOR: #231f20; FON