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SPECIAL
ALUMINIUM SMELTING TECHNOLOGY
INDUSTRY
Chips versus briquettes: How the aluminium
industry can effectively and efficiently recycle scrap
G. Tucholski, Ruf US
For the aluminium industry, there has
long been an issue of how to recycle,
transport and / or dispose of scrap metal
and swarf (machining chips). Many in the
aluminium industry recycle their scrap
aluminium in the form of chips. These
chips can provide additional revenue
through recycling. However, there are
some challenges with recycling aluminium
chips as chips are bulky and tend to be
difficult to transport. Also, it is difficult,
if not impossible, to remove the machining
coolant or lubricant, which leaves
manufacturers with wet and oily chips.
Recyclers often will not accept wet chips,
or will charge a fine.
Companies throughout Europe, and
now in North America, have discovered
a new way to process aluminium scrap:
briquetting. Briquetting offers an efficient
and effective way to recycle aluminium
scrap, and it also solves many of the common
problems that arise from recycling
aluminium in the form of chips. Briquettes
are consistent in shape, size and
weight, and so they are easy to stack and
transport, besides having other advantages
that will be addressed later in this
article.
What is briquetting?
At its most basic level, briquetting is a process
that compresses metal scrap and swarf
into compact, easy-to-manage round blocks
(briquettes) with densities and resale values
that rival those of massive metals. Briquet-
Aluminium briquette and chips
As the technology and performance of briquetting
have advanced, so
have the potential benefits that
it holds for the aluminium industry.
Briquetting boosts the
bottom lines by adding value
to the waste stream. There are
three main advantages of briquetting
for manufacturers:
The melting factor: The biggest
advantage of briquetting
aluminium is that briquettes
melt better than loose chips.
Comparing the same weight of briquettes
versus chips, briquettes will produce more
aluminium after being melted. Chips tend
to burn, whereas briquettes melt more like a
solid. This is the main reason smelters use briquettes
instead of chips – they are going to get
more metal out of their bath than if they were
using chips. When the process is complete,
more material is recovered with briquettes,
which means more revenue.
Removing coolant or oil: Through the briquetting
process, coolant or oil lubricant that
saturates aluminium drains out more easily.
This liquid can then either be recycled for adting
has been used for more than 50 years,
but its technology and benefits have evolved
greatly over the years. For example, old-style
briquetting machines were big, loud and had
high-maintenance costs.
Today, briquetting systems made by companies
like Ruf are just the opposite. Our briquetting
systems are engineered specifically
to run reliably and efficiently, and to deliver
the same or better production rates while using
less horsepower.
The benefits for the aluminium industry
ditional revenue and / or savings (especially
when it is mostly oil), or it can be disposed
of safely and more easily. There are two big
advantages to being able to remove the coolant
or oil:
First, it allows the manufacturer to do the
recycling in-house instead of having to go
through a third party, which reduces costs.
Second, when a manufacturer sells chips that
still have coolant and oil on them, the manufacturer
will be penalised. Transporting wet
chips also creates a potential problem – it is
Briquettes are consistent in shape, size and weight,
therefore easy to stack and transport
hazardous if the oil or coolant drips onto the
road during transport, so extra precautions
and steps must be taken. This penalty, along
with the liability of transporting wet chips, can
really add up.
Space, transportation and storage: When
dealing with chips, there have always been issues
with storage and transportation because
chips are loose, take up much more space
and cannot be stacked or contained neatly.
Briquetting solves all of these problems. Briquettes
are stackable, which makes them easy
© Ruf
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