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FUNDAMENTALS OF RECYCLING PROCESSES 53

2.8 Fundamentals of

Recycling Processes

2.8.1 INTRODUCTION

An understanding of the recycling industry and the related processes can be very ben-
eficial when evaluating the life cycle of a product. In addition, a basic understanding
can aid managers and engineers in making better decisions in regards to recycling and
disposal options. Following is a brief summary of some of these benefits:

■ Gain a better understanding of recycling options and the different roles that mate-
rial recovery facilities, processors, and material brokers play in the process.
■ Gain an understanding of the recycling process and the process flow for materials
as they leave a facility.
■ Gain an understanding of the material separation needs based on the recycling
process for each material type.
■ Gain an understanding of the recycling process to design better processes and prod-
ucts to reduce the environmental impact.
■ Learn more about the LCA process and develop more accurate inventory audits.

This section provides an overview of the recycling industry which includes brief
discussions of the business entities operating in the field. In addition, overviews of the
recycling processes for major waste items are also provided. The intent of this section
is to expose the reader to basic terms and processes in the field, not to provide a
detailed or comprehensive analysis.

2.8.2 RECYCLING INDUSTRY OVERVIEW

The recycling industry is comprised of five primary entities that work together to get
recyclable materials from the point of generation as a by-product or waste to the stage
where they can be used again as raw materials. Figure 2.13 shows the recycling process
overview. These entities are

1 Haulers—These companies transport materials between entities, including the gen-
eration facility, consolidation points, and processing facilities. Oftentimes, these
companies will lease a semitruck trailer to the generating facilities to consolidate
and store recyclable materials before transportation to a consolidator or depot.
2 Material recovery facilities (MRFs)—An MRF is a specialized plant that receives,
separates, and prepares recyclable materials for marketing to end-user manufacturers.
There are two types of MRFs: clean and dirty. A clean MRF (Fig. 2.14) accepts
recyclable materials that have been collected in comingled wastes from curbside
collection separated at source from municipal solid waste generated by either
residential or commercial sources. There are a variety of clean MRFs. The most
common currently are two-stream MRFs, where source-separated recyclables are