Sector Assessments

APPENDIX I

AN APPROACH TO SOLID WASTE MINIMIZATION IN THE PAPER INDUSTRY

Manfred K. Buder, Solid Waste Minimization Project Manager Weyerhaeuser Company - Tacoma, Washington

Since the late 1980s the paper industry has written numerous success stories in the reduction of the solid waste it generates and disposes. According to a survey by NCASI (National Council for Air and Stream Improvement), in 1989, the industry generated over 13 million tons of process wastes, nearly all of which were land filled. Most of this waste consists of effluent treatment solids ("sludge"), boiler ash, lime wastes, and wood debris. In recent years the industry has made inroads in shifting much of these residuals to useful alternative practices, such as energy recovery and land application.

Weyerhaeuser Company ascribes to an integrated approach for managing the solid wastes from its manufacturing facilities. This means the coordination of a "full tool kit" of waste management options and their implementation across all of Weyerhaeuser's facilities. A key part of this strategy is to make progress in reducing the generation of and finding beneficial uses for these solid residual streams. There are five key drivers for the company's waste minimization effort:

• Environmental protection and tightening regulations
• Stakeholder expectations
• Company policy to conserve resources and minimize waste
• Landfill depletion and high replacement costs
• Economic benefits: avoided disposal cost and material recovery credits.

Accordingly, Weyerhaeuser's mills in Georgia have made and are continuing endeavors to minimize their solid waste streams. The Flint River pulp mill recycles scrap metal, office paper, and aluminum cans. The mill has also made significant strides to reduce fiber loss, thereby not only conserving raw materials, but also decreasing the quantity of primary effluent treatment sludge that needs to be dewatered and hauled to the landfill. Our composite panels mill at Adel provides another example of solid waste minimization. Instead of land filling its sanderdust waste, the mill sells it to a Florida utility company that uses it for fuel. Per unit of product, our sawmill at Barnesville landfills less of its manufacturing wastes that any other Weyerhaeuser sawmill. This is largely because of the mill's resolve to recycle these residuals as raw materials for particleboard manufacture (at Adel), for use by horticultural and landscaping companies, as a fuel (both internally and at Flint River), and for other beneficial uses. The Barnesville sawmill has also undertaken pollution prevention measures to reduce its generation of log yard waste to a level that is unmatched by similar mills within the company.

In support of this companywide effort, a technical team from the Corporate R&D group has been charged with providing assistance to Weyerhaeuser's pulp, paper, paperboard, and wood products mills to minimize solid waste generation and disposal. This Solid Waste Minimization (SWMin) Team works with the mills and with sister entities at the corporate offices to obtain data, evaluate solid waste reduction opportunities at mills, develop mill SWMin plans, and stay abreast of pertinent technologies. At the heart of the program for the past several years have been the SWMin studies conducted at Weyerhaeuser manufacturing facilities. The SWMin Team with the help of mill staff, obtains data on recurring, non-hazardous solid waste streams, and assists the mills in identifying and capturing significant waste reduction and utilization opportunities. Since the onset of the decade, SWMin studies have been completed for nearly all of the company's thirteen pulp, paper, and paperboard manufacturing sites. In the last couple of years Weyerhaeuser's SWMin Team has been busy working with various wood products facilities.

SWMin is a seven-step process. The first step is the planning and coordination of the study with the mill. Second, the SWMin Team, typically two engineers and two technicians, conduct a week-long onsite survey to identify waste steams and their sources/destinations, glean facts and data, take samples, and obtain ideas and other input from mill staff. In the third step, the solid waste streams are screened down to a manageable number of key streams for which various short- and long-term minimization alternatives are identified. Three screening criteria are used: annual disposal cost, annual recovered value of the stream, and associated environmental issues. Also, at this point in the process the SWMin Team surveys potential uses and users for selected residual streams as a reality check against some of the utilization alternatives being considered. In Step 4, the most promising combinations of waste streams and minimization alternatives are further developed and evaluated based on roughly estimated life-cycle economics. The "top" economic opportunities are ranked by their net present values and reported to the mill. These opportunities are reviewed and revised, as appropriate, with mill staff in the fifth step of the SWMin process. The purpose of this step is to select a reduction target, finalize the SWMin project roster, and develop a five-year SWMin plan. Step 6 is the implementation of this plan and Step 7 is the documentation of SWMin progress against the plan. The SWMin Team is available to the mills for technical support during the implementation and documentation phases. Of course, since costs, markets, production, and other things do change over time, it will be necessary to loop back and revisit some earlier steps in the process from time to time.

Typically, 50 to 100 solid waste streams, some of them very small on a relative scale, are identified at each company pulp and paper mill. Most of these wastes end up being land filled, usually onsite. Others are burned, typically in the power boiler, or land applied. Secondary effluent treatment solids are impounded in lagoons for the most part, since few company mills use activated sludge treatment systems. Small, but growing, quantities of the mills' solid residuals are recycled.

The largest solid waste categories being generated by the mills are various woodwastes, boiler ash, effluent treatment sludges (primary and secondary), recausticizing wastes (dregs, grits, lime, etc.), and general mill trash. Minimization of these types of streams is certainly challenging. As examples, the SWMin team and Weyerhaeuser mills have evaluated, and in many cases implemented, the following SWMin approaches:

• Woodyard debris: (1) debris separation into hog fuel, rocks, and fines (soil supplement); and (2) woodyard paving.
• Boiler ash: (1) boiler upgrade to improve combustion efficiency, (2) flyash screening and char reinjection, and (3) ash utilization as a soil supplement or construction material.
• Primary sludge: (1) avoiding mixture of ash, line, and other separable streams flowing into the primary effluent treatment system, (2) spill and leak control, and (3) recovery of fiber for internal or external use, or for energy recovery as a fuel.
• Grits and dregs: (1) purchased lime quality control, and (2) washing and land application.

Although there are similarities among mills, the SWMin Team found the mills to be at different stages of waste management along the hierarchy of alternatives (i.e., from disposal up through recycling and source reduction). However, significant opportunities exist for cost effective improvement at each facility surveyed. One result of these studies has been to make the mills more aware of the solid wastes they generate, must manage, and can minimize through examination of the projected economic benefit. The risk mitigation "stick" and opportunity "carrot" are significant enough to encourage the mills to place higher priority on tracking their solid wastes and planning for their future reduction. It is interesting to note that those Weyerhaeuser mills that have made the greatest effort to improve and have realized the associated benefits tend to be the strongest advocates for further SWMin progress.