Overlooked by the Industry?

Processing facilities (or packing plants), paper stock operations and MRFs play a vital role in the supply of fiber to the country’s paper and paperboard industry. However, because of economic difficulties associated with operating such facilities, they have not received the same attention as other aspects of paper recycling.

Traditionally, the approach to paper stock plants was to keep them simple—have the lowest possible capital investment and handle highly source-separated materials. Getting the materials baled and out the door is always top priority. As technology moves forward with higher recovery rates, paper recycling processing facilities are being asked to handle more mixed incoming fiber and other material streams. As processing facilities’ size and complexity grow, more attention to their design, construction and efficient operation is needed.

There are often complaints about the economics of recycling systems, especially where processing operations are concerned. Volatile recovered paper market prices, at times, make it almost impossible to have viable sophisticated processing facilities (although those that complain about market prices of the last two years would be well advised to examine the ultra-low prices of the early 1990s). Complaining does not do anyone any good. What one must do is gain control of that over which one has obtainable control.

The things that can be controlled include collection and processing costs. One should begin by benchmarking the current operations. Then, analyze, make changes, measure results and set new benchmarks. Keep this process going so things continue to advance and change.

There is a strong industry trend toward reducing collection costs, using new techniques that result in less trucks and routes. To accomplish this, experts are fully realizing the benefits of full-cost accounting for the services of recycling. From the generator to the mill’s dock, it is clear that the careful integration and optimization of costs will yield the most profitable operations.

With the advent of residential curbside recycling in the late 1980s, a number of processing facilities were equipped to handle paper, bottles and cans (glass, metal and plastic). The latest evolution in MRFs is the trend towards single-stream processing-mixing the fiber and bottle or can stream, at the source.

Single-stream recycling is dependent on technology to separate the incoming materials into marketable products. Two types of equipment are integral to these processing operations; disc screens and incline sorting machines.

Specially designed disc screens operating with proprietary shaped discs separate paper from containers with over 90% efficiency. Screen capacities are up to ten tons per hour at these efficiency levels. Higher levels can be reached when a second screen is used in series in a clean-up or polishing mode.

Inclined sorting machines are specially designed slanted conveyors with proprietary belt beaters that are able to sort paper from containers, and with more than 90% efficiency. These machines have individual capacities of up to eight tons per hour at these efficiency levels. Higher efficiency levels can be obtained when the incoming stream is split and two parallel incline-sorting machines are used.

One thing that appears to be missing with many processing facilities operating throughout the United States is viewing them as manufacturing facilities. They are no different than any other operation that takes in a raw material (even given recyclable variability) and performs value added functions to produce a finished product/commodity. Baled paper is, indeed, a "finished product" and the virgin paper mill is a great analogy. (Those who don’t consider trees variable in their composition should consider that rocks, dirt, bark, and knots must be removed before the incredibly complex pulping and bleaching operation. This produces a finished product that looks nothing like the incoming raw material.)

The following factors have evolved in manufacturing over the last fifty years and are applicable to recycling processing operations:

There are a myriad of other areas where minor technological advances must take place. One example is bar coding finished materials for easy identification, both at the processing facility and at the end user mill.

Single-stream processing for residential recycling has been met with a significant level of controversy. The earliest residential recycling programs featured highly source-separated collection (with as many as eight separate bins on the collection vehicles) and minimal value added at the processing facility other than densification. These programs, still appropriate only in small communities, had very high collection costs and, typically, could not be economically justified. The next evolution, first seen in the western United States, was the three-bin system with old newspapers in one, glass in another and aluminum and steel cans in a third. This approach caused the birth of the MRF with some fairly simple true processing operations necessary to produce the commodities.

The next step, which began in the eastern United States, was to mix the bottles and cans together and add plastics.

Another step, single-stream collection and processing, has begun in the western United States. After ten years of developing technologies to process and manage co-mingled containers, technology is now forging ahead with advanced processes to reduce residential curbside recycling program cost. There is convincing data that for many programs, the combined collection of paper with containers in single-stream will save the collector big money. With single-stream recycling, we can consolidate truck collections as well as automate them to substantially reduce costs. Studies performed by RRT have confirmed that single-stream collection programs will increase collection productivity well over 20%. It simply takes less time per stop.

This approach is not without challenges. Undertaking a single-stream program requires substantial planning as well as an understanding of all impact issues. The most significant issues are economic. A complete revamping of the infrastructure is needed. Collection costs will go down, but some of the savings will be offset by increased costs for processing at the MRF. Diversion rates will go up, but some of the savings will be offset by the higher residue rates. These issues and others have brought some concern and hesitance. The bottom line is that the winners in this game are those that will quickly go through the planning and re-engineering process and get going towards the path of single-stream recycling.