Grantee Research Project Results

Final Report: Value-Added Composites From Foundry Industry Waste Materials

EPA Contract Number: 68D02035
Title: Value-Added Composites From Foundry Industry Waste Materials
Investigators: Merrington, Adrian
Small Business: Resource Recovery Corporation of West Michigan
EPA Contact: Richards, April
Phase: I
Project Period: April 1, 2002 through September 1, 2002
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2002) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , SBIR - Waste , Small Business Innovation Research (SBIR)

Description:

The main objectives of this Phase I research project were to recover the economical value of foundry industry by-products and eliminate environmental and economic burdens associated with current disposal practices. Developing processes to handle and applications to use composites produced by compounding foundry waste and plastics will help to achieve these objectives. The technical issues to be addressed in the Phase I research project are essentially those of quality, process, and product:

• Assess the quality of and variation in the fines recovered from foundries.
• Evaluate different processes and polymeric binding materials for use in the production of composite, recycle-content parts.
• Define applications for these recycle-content parts.

The activities designed to ensure that Resource Recovery Corporation of West Michigan (RRC) can accomplish the objectives described above include:

• Fines collection
• Characterization of recovered fines
• Polymer selection
• Process definition
• Composite characterization
• Economic analysis
• Application development
• Initial customer product evaluation.

Initial concepts for products were limited to low-cost, high-volume applications. The plan was to use these applications to pull the recycling technology through in anticipation of subsequently finding a higher value application. Considerable activity during this project was directed towards finding higher value applications while developing the technology to ensure that RRC eventually will be able to bring the fines/plastics composite products to market.The main objectives of this Phase I research project were to recover the economical value of foundry industry by-products and eliminate environmental and economic burdens associated with current disposal practices. Developing processes to handle and applications to use composites produced by compounding foundry waste and plastics will help to achieve these objectives. The technical issues to be addressed in the Phase I research project are essentially those of quality, process, and product:

Summary/Accomplishments (Outputs/Outcomes):

Composites comprising up to 93 percent of the foundry industry and having density up to 160 percent that of concrete have been produced. A comprehensive understanding of the foundry fines streams has been recorded, and initial blending characteristics with a series of virgin and recycle plastics (high-density polyethylene, polyvinyl butyral, thermoplastic olefin, acrylonitrile
butadiene styrene, and mixed municipal waste) was established.

The composites, depending on plastic binder, may be stronger than concrete; be produced by a variety of manufacturing techniques (extrusion, pelletization, compression molding, injection molding, sheet extrusion); have excellent vibration and sound deadening properties; and be competitively priced with parts produced using incumbent materials and processes. Additionally, some high-value applications are being investigated.

The most significant results from this Phase I research project include:

• Plastic/fines composites have value.
• Plastic/fines composites have significant mechanical properties.
• Fines can readily be separated into high- and low-density streams.
• Thermoplastics can act as a binder in fines/plastics composites.
• Thermoplastics fully wet-out the foundry fines with a simple mixing apparatus.
• Thermoplastic binder and fines choice can significantly effect composite properties.
• Plastic/fines composites can be processed using conventional plastics equipment and techniques.
• Plastic/fines composites may be used to produce parts that are less expensive and have better mechanical and physical properties than concrete.
• Plastic from municipal waste may be used as a binder if appropriately compatibilized.

The innovative approach of combining waste from two industries (foundry fines and plastic scrap) to produce a series of composites with useful properties has been demonstrated. Commercial routes for these composites are opening through interactions with domestic and industrial furniture producers and domestic appliance manufacturers.

Conclusions:

The successful completion of this Phase I research project has confirmed the hypothesis that useful materials can be blended from foundry waste residual fines and plastics. During this 6-month project, RRC has:

• Developed a good understanding of the fines, their size, composition, and physical properties.
• Analyzed different plastics for application as binders and showed them to be efficacious in various applications.
• Evaluated various production techniques and identified some limits.

However, much work still remains. RRC needs to finalize composite compositions and manufacturing techniques best suited to each specific application. A number of applications are being investigated from low-cost, high-volume products identified in the original proposal to some intriguing higher value possibilities. A Phase II research project would allow RRC to fully develop these composites and bring them to commercialization in a number of applications.

Supplemental Keywords:

Sustainable Industry/Business, RFA, Scientific Discipline, Waste, Technology for Sustainable Environment, Sustainable Environment, Municipal, Economics and Business, Environmental Engineering, municipal waste, waste recovery, recycling, emissions control, reuse, waste processing, composites, emission controls, environmental sustainability, green design, municipal solid waste landfills, recovered materials, composite parts manufacturing, clean technologies, cleaner production, environmentally conscious design, foundry industry, spent foundary sand, waste markets, waste recycling, resource recovery, industrial innovations, waste management