Plastics, Rubber, and Paper Recycling - American Chemical Society

Chapter 25

Recycled Paper: Raw Material Supply and Other Considerations 1

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Tom Friberg , Gordon Cawker , and Jan Huston

Downloaded by UNIV OF PITTSBURGH on May 3, 2015 | http://pubs.acs.org Publication Date: May 5, 1995 | doi: 10.1021/bk-1995-0609.ch025

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1Corporate Research and Development, Recycling Business, and Paper Company Engineering, Weyerhaeuser Company, Tacoma, WA 98477

Presently, close to 40 million tons of waste paper is recovered each year in the U.S. This is expected to grow to 50 million tons by the year 2000. During this time, there will be significant changes in the sources and methods of paper recovery. Recovered paper grades will change in response to papermaking and end-product requirements. Much of this will be cost-driven though government regulation will continue to impact collection and utilization. Conceptual Model for Recycling A convenient model for evaluating recycling has three parts. Thefirstis the raw material supply. Where does it originate, what is its character and quality? What kind of volumes, prices and costs are associated with its procurement? The second area is the production capacity. This is the technical conversion of the raw material into the final product. For recovered paper, this is the repulping, cleaning, screening, and deinking (if necessary) to produce a recycle pulp, paper or paperboard product. The third area is market demand. This area deals with the end-use requirements and specifications for a recycle content product. It also includes volumes and prices. In this paper, we will talk only about raw material supply and market demand. Raw Material Supply Recovered paper specifications. Over the years, a set of "origin-based" recovered paper grades have developed. There are approximately 50 standard grades and 30 special grades based upon the type of paper collected. Table I has aggregated these grades into their major categories. The definitions used in stipulating these grades are very brief descriptions of the recovered paper (see Figure 1). In addition to the brief description, limits are placed on the level of contamination that is acceptable. Thefirstare outthrows which are contaminating papers other than those indicated in the description. An example outthrow would be old corrugated when 0097-6156/95/0609-0296$12.00/0 © 1995 American Chemical Society In Plastics, Rubber, and Paper Recycling; Rader, C., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1995.

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Recycled Paper: Raw Material Supply

Table I: Major Categories of Waste Paper (1) •


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Pulp Substitutes •• High quality pre-consumer white Ledger •• High quality post-consumer white Office Waste Paper (OWP) Old Newspaper (ONP) Old Corrugator Containers (OCC) Old Magazines (OMG) Mixed Waste Paper •• Office (MOW) •• Residential (MRW)

Outthrows The term "Outthrows" is defined as "all papers that are so manufactured or treated or are in such a form as to be unsuitable for consumption as the grade specified."

Prohibitive Materials The term "Prohibitive Materials" is defined as: a. Any materials which by their presence in a packing of paper stock will make the packaging unsuitable as the grade specified. b. Any material that may be damaging to equipment.

EXAMPLES: News Consists of baled newspapers containing less than 5% of other papers. • Prohibitive materials may not exceed 1/2 or 1% • Total Outthrows may not exceed 2%

Corrugated Containers Consists of baled corrugated containers having liners of either test liner, jute or kraft. • Prohibitive materials may not exceed 1% • Total Outthrows may not exceed 5%

Figure 1. Grade definitions (1).

In Plastics, Rubber, and Paper Recycling; Rader, C., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1995.

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found in a newsprint bale. The second limit is prohibitives which are materials that are not paper (metal, rocks, etc.). (1) Sources of recovered paper. Traditionally, recovered paper has been collected from easily available, larger volume sources. These include commercial operations, retail stores, offices and residences. Examples are wholesale and retail operations for old corrugated containers, residences for old newsprint, and larger office buildings and commercial institutions for ledger grade paper. These "low-hanging plums" of relatively easy to access recovered paper are generally collected with varying degrees of source separation. In the future, we will see sourcing of smaller generators of recovered paper, such as small offices, multitenant buildings, and residences. There is a trend toward commingled collection. This will impact quality, consistency and cost. The smaller generators will require more innovative sourcing methods to reduce unit procurement costs. Types of collection. Because of logistical and cost advantages, most traditional recovered paper sourcing has been "source separated." This provides larger volumes of discrete grades which are sorted at time of pick-up or drop-off. We are seeing a trend toward commingled collection of waste paper. This is because many of the collectors are waste haulers/handlers and, for them, moving volume is important. Many cities and counties attempting to comply with state mandated recovery goals view commingling as an efficient means to satisfy these numerical quotas. When viewed in the context of the paper industry and their requirements for sustainable recovery, it is clear that such efforts may only serve to shift the burden of "disposal" from one group to another unless we can cooperatively design recovery to meet enduser requirements and existing technological capabilities. Commingled collection can have lower initial cost in collection and handling. It also has the potential for more flexibility in responding to market opportunities by selectively sorting the commingled collection. It generally has higher processing costs. Collection and processing. Recovered paper may be picked up in large, presorted batches from commercial organizations; small, presorted batches as from some residential collection; or in large and small batches from commingled collection. Paper may also be dropped off at specified sites or brought directly to a material recovery facility or packing plant. In none of these cases is garbage included with the recovered paper. With commingled collection, it may include many varieties of paper and has a higher level of contamination. Regardless of the method of collection, all recovered papers are received, weighed and categorized. There may or may not be sorting, depending upon the purity of the collected material and the immediate market demands for the various grades. Sorting may vary from simply dumping the paper on thefloorand pushing it around to highly mechanized systems of screens, magnets, and picking conveyors. After processing through the plant, most recovered paper is baled. The "bale" is the common commercial and transportation unit and weighs about 1600 pounds (range 500-2000). Bales may vary considerably in size, but are generally 4 ft square by 5-6 ft long and are wire banded. Tight, uniform bales permit relatively easy loading,


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transportation, and unloading. In cases where there are large volumes and steady customers, bulk compaction into trailers may be used. Government influences. Free market conditions are not the only factor that are influencing recovered paper collection and utilization. Government is playing a significant role. This has been a difficulty for most in the commercial collection and recycling business because recycling is an "incremental" business. Recovered paper supply is inelastic in the short term because of the required infrastructure for collection. With the large step jumps in supply that government regulation can trigger, recovered paper prices may be extraordinarily volatile. The very low prices during the 1991-1993 period were largely the result of the collection systems fostered by governments during the late 1980's. We are seeing government intervention in the area of recycling and recovered paper collection because jurisdictions have set goals for waste diversion from landfill. To accomplish these goals, governments are using a variety of tools: recovery rates, bans from landfill and advance disposal fees. Most every state established recycle goals that ranged from 25-70%. Some states even enacted landfill bans that prohibited the disposal of paper. Market Demand The market...a tale of two cultures. On the waste paper supply side, we have the collectors, haulers/handlers, and recyclers, and on the utilization side, we generally have the pulp and paper mills. Therein lies a tale of two cultures. The waste haulers and handlers are interested in the collection and low-cost transportation of material from one location to another. This is very different from the requirements of the pulp and paper mills, which strive toward constant and controlled raw material characteristics. Utilization of recovered paper. The bulk of the 38 million tons of paper recovered in 1994 was used as a raw material for new paper products. It also went to other uses such as insulation, molded pulp, fuel compost, etc. Recovered paper is used domestically as well as exported to markets throughout the world. For perspective, the percentage of recyclable paper used in overall fiber furnishes in the US did not change appreciably in the decades of the 70's and the 80's. Recovery rates really began to climb in the late 80's and reached 40% in early 1993. The new goal of 50% recovery is set for the year 2000. Figures 2 and 3 show overall US recovery and utilization data. (2) Recycled fiber usage varies by type of paper production. For instance, tissue and containerboard producers utilize a much higher percentage of recovered paper than fine paper producers. See Figure 4. Re-use considerations. So far, the discussion has dealt with where the paper has "come from." Re-use considerations depend upon where the paper is "going to." In general, waste paper fibers are either mechanical (from groundwood, thermomechanical, or semi-chemical/mechanical) or chemical (kraft or sulfite pulping). The chemical fibers will be either unbleached or bleached. While the




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species of origin for waste paper fibers may vary dramatically, this is of less importance in recycled fiber use. Once fibers are recycled, they tend to perform as though they are hardwood fibers. While far beyond the scope of this paper, it is important to note that there are other considerations beyond the waste paper fiber itself. They include the coatings and sizings that are used in paper and the inks, coatings and varnishes that are used on paper. There are also the impacts of contaminants such as glues, binders, adhesives, staples, and other tramp material that can be inadvertently or otherwise included with the waste paper. Recycled paper properties. Three general property areas are strength, bulk, and surface characteristics. Strength (tensile, tear, compression, internal bond, etc.) is important principally in packaging, exemplified by the use of recycle fiber in liner and medium linerboard for corrugated packaging. Recycle fiber tends to be stiffer than virgin fiber, so this contribution to the bulk of a sheet may be useful. Lastly, and particularly important in printing, writing and communication papers, are the surface properties. These include smoothness and linting and the optical properties like brightness and dirt. There is a common misperception that all recycle fibers lose strength and other properties upon recycling. Some of the strength properties of chemically pulped recycle fibers are diminished. Interestingly, select optical and printability properties are generally improved through recycling of chemical fibers. With the case of mechanical fibers, such as fibers originating from newspapers, strength properties are not lost. Fiber flows. Traditionally, waste paper has been used in direct substitution for like products or it has been "downcycled." Examples of direct substitution are old newspapers (ONP) going back to newspapers or old corrugated containers (OCC) going back into the liner or medium of new corrugated containers. Downcycling is exemplified by white office paper going into tissue use. We are now seeing interactions and substitutions of waste paper. This is the start of a transition from basing waste paper use on where it has "come from" toward using waste paper based on where it is "going to." The four major grades involved in interaction and substitution are old newsprint (ONP), old magazines (OMG), old corrugated containers (OCC), and office waste paper (OWP). Increasingly, old magazines are incorporated into the production of newsprint. Also, we are seeing mixed waste paper coming from offices and residences utilized in the production of liner and medium for corrugated containers. One of the most dramatic changes is the use of old corrugated containers for white paper and bleach board. This "upcycling" is the mild chemical repulping and bleaching of old corrugated containers to produce a white fiber that is a higher value than the original fiber. Government influences. The market side of waste paper utilization is also affected by government regulation. At present, governments are driven to develop markets for materials collected through recycling. The most common tool used by government is recycle content. An example at the Federal level is the procurement guidelines for printing and writing paper. This establishes general levels of 25% by


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Table II: Alternative Uses for Recovered Paper, 1990 and 2000 (5) (tons per year)

Molded Pulp Insulation Fillers and Fibers Animal Bedding Internal Packaging Hydromulch Wallboard Medium Density Board

1990 500,000 300,000 260,000 125,000 100,000 100,000 90,000 80,000

2000 1,000,000 600,000 (1) 300,000 (1) 250,000 (1) (1)

(1) No information.


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1995 and 35% by 1998. It is expected that these guidelines will be reflected by state and local governments. (3) Alternative uses for waste paper. Not all waste paper that is collectedfindsits way back into paper or paperboard. Presently, more than one million tons annually is used in products such as molded pulp, insulation, hydromulch, animal bedding, and filler fibers. Please see Table n. This does not include fuel which is a growing use of paper that is too low in quality to be recycled into paper. Challenges and Opportunities for Recycle Paper


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Going deeper into the waste stream- We are seeing trends toward wider varieties of paper collection and smaller volume sources. We are also seeing substitutions in utilization of the waste paper. Develop wider "scaled" operations - We are seeing both smaller and simpler recycled paper mills, as well as larger volume use by existing and new mills using recycle paper. Preserve or recover recycled fiber properties - Recycling does change the properties of chemically pulped fibers. We need to see improvements in strength, bulk, and surface and optical properties. Develop improved recycling processes- Existing processes need to be streamlined, upgraded, and better understood for repulping, decontamination, and deinking of waste paper.

Summary With life cycle considerations and resource conservation, recovered paper will play an ever increasing role. As a raw material, it can serve in many ways. It can be reused, recycled, burned for energy, composted, and, what does go to landfill, will ultimately degrade. With 29 existing recycling plants, Weyerhaeuser expects to grow by a factor of four by the year 2000. Innovative sourcing coupled with increased sorting will be required to meet the logistical issues of the increased volume flow. Finally, paper and paperboard process and market requirements will demand informed procurement, grading, and supply of recovery paper. References 1. 2. 3. 4. 5.

Institute of Scrap Recycling Industries; Scrap Specifications Circular; Institute of Scrap Recycling Industries: Washington DC; 1994. Options Review for Recycling Division Information Package; Weyerhaeuser Company: Tacoma, WA; 1994. Alig, Joanne; State Legislation Focus on Market Development; Recycled Paper. Vol. 4, No. 5, 1994, January, 1-8. Recycled Fiber in North America; Changing and Emerging Opportunities in the 1990s; Jaakko Poyry: Tarrytown, NY; 1992. Friberg, T.; Resource Recycling. 1993, January, 26-33.

RECEIVED July 13, 1995


Plastics, Rubber, and Paper Recycling - American Chemical Society

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