CHAPTER 4 – Environmental Technology

The
metalcasting industry must actively and creatively address environmentally
responsible manufacturing. Being active means adapting best-available
technology. Being creative means developing innovative new process and
materials technology. Scientifically sound technical information must be
incorporated in a holistic approach. Existing infrastructure realities and
technical capabilities must be recognized to form strategies with
long-range goals, but realistic timetables, to form a global environmental
policy.

AFS
Topic

Project
Title

Funding

Environmental, Health & Safety

Foundry
By-Products Technical Data- PSU

CMC

Environmental, Health & Safety

Non-Incineration Volatile Organic Compounds Reductions-
PSU

CMC

AFS
Research Reports for sale

Project
Title:

Development of Technical Data to Validate Performance of
Foundry Byproducts in Hot-Mix Asphalt and Controlled Low-Strength
Material

Investigator:

Paul
Tilkalsky, Pennsylvania State University,., Tel:
814-863-5615
Hussain Bahia, University of Wisconsin at Madison,
Tel: 608-265-4481

AFS
Topic:

Environmental Health and Safety

Funding
Sources:

Department
of Energy Office of Industrial Technology
AFS Industry
Sponsors

Funding:

Total $560K
(In-Kind $364K)

Energy/Environment:

52 trillion
BTU

Contract
Start/End Date:

December
2000 to December 2003

The focus
of this research is to find alternative uses for the foundry sand to
eliminate the need for some, or all, thermal reclamation and the
energy costs. Approximately 80 percent of foundry sand will have to
be thermally reclaimed (heated to eliminate plastic binder) to be
recycled. An alternate approach is to develop markets for spent
foundry sand to avoid the capital investment and operating costs
associated with thermal reclamation. Nearly 27 million tons of
foundry sand is disposed of annually in the United States. The need
to beneficially reuse the nation’s natural resources has enormous
potential to recycle or reuse foundry sand as prime feedstock for
other industries. This will turn a foundry liability into an
asset.

Developing specifications and guidelines plus documenting
applications for controlled low-strength material and hot-mix
asphalt helps to create these new markets. These applications are
well suited to the foundry sand reuse because they can be used in
both large and small communities, and ready-mixed concrete producers
can partner with local and regional sources of foundry sand to
develop controlled low-strength material and hot-mix asphalt
mixtures containing foundry sand.

The sands provide a required component of controlled
low-strength material and hot-mix asphalt without increasing the
cost or diminishing the engineering properties. However, the sands
must meet the same quality as market alternatives. To meet these
quality levels, the engineering properties of controlled
low-strength material and hot-mix asphalt containing foundry sand
must be carefully designed and documented for specification
development and acceptance.

Most recently, the application of foundry sand to
agribusiness holds exceptional promise. Sand blended in the correct
proportion to many soils can control the moisture content to improve
agriculture yields. These markets are typically near foundries so
shipping costs do not become an economic hurtle. More information on
all foundry byproduct applications can be found at the Foundry
Industry Recycling Starts Today (FIRST) web site,
http://www.foundryrecycling.org/.

Project
Title:

Non-Incineration Treatment to Reduce Benzene and VOC
Emissions From Green Sand Molding Systems

Investigator:

Robert
Voigt, Penn State University, Tel: 814-865-7601

AFS
Topic:

Environmental Health & Safety

Funding
Sources:

Department
of Energy Office of Industrial Technology
AFS Industry
Sponsors

Funding:

Total $400K
(In-Kind $18K)

Energy/Environment:

540
trillion BTU over ten year implementation
30-percent reduction in
VOC form high production iron foundries

Contract
Start/End Date:

October
1998 to June 2002

The goal of
this research is to understand and further develop cost-effective
non-incineration techniques that will significantly reduce VOC
emissions from foundries. In sand systems the bentonite clays, the
seacoal or carbonaceous additions, and the other organics from core
binders and additives degrade during successive cycles of reuse.
Bond water and seacoal additions are made during sand recycling to
maintain sand system dynamic equilibrium. Organic compounds also
build up on the sand and additive surfaces. These are the source of
benzene and VOC emissions for high-production operations. Advanced
oxidation technology development will allow a waste stream (active
clay and seacoal from baghouse dusts) to be effectively used as a
substitute for new bond purchases.

At
several Advanced Oxidation (AO) systems in production foundries
across the U.S., green sand process water is conditioned with small
additions of ozone and hydrogen peroxide and is sonicated
(irradiated by ultrasonic waves) to create opportunities for
volatile organic compound (VOC) destruction during foundry pouring,
cooling and shakeout cycles. Tests at Penn State also explored an
underwater plasma add-on to this AO system. AO processing
simultaneously diminishes air pollutants by 30%-70%, improves green
sand system performance, and diminishes clay and coal materials used
by 10%-30% through improvement in clay activation and other
phenomena. These effects are achieved for AO-clean water systems
where AO-treated water is incorporated into green sand systems, as
well as in AO-black water and AO-dry dust-to-black water systems
where clays from wet recovery systems or baghouse dusts are returned
to the sand system as part of AO-treated slurries.

AO – clean water system

AO – dust to blackwater
system