Page 407 - Solid Waste Analysis and Minimization a Systems Approach

CASE STUDY 385

8 years in 1996. The mill has the added difficulty of not being able to landfill the waste
in a municipal solid waste landfill due to the waste’s high water content. Reducing
generation of waste fiber and solid waste at the facility will extend the life of the land-
fill and is an important goal for the company.
Developing a formal pollution-prevention program and performing the associated
assessments can often help companies identify Pollution Prevention (P2) options, even
if they are already doing P2. Performing initial and detailed assessments of pollution-
prevention opportunities is an integral part of developing a P2 plan. The mill owners
were a little skeptical of the program at first, because they were already aware of
pollution-prevention concepts and had implemented some projects. However, the
company used the P2 process (as required in the Supplement Environmental Project
[SEP]) to define previously unidentified projects, better track waste streams and their
associated costs, and to reinvestigate previously identified projects that had never been
implemented.
The mill developed a P2 team that included members of all levels, from staff to
upper management. Empowering the team to make decisions on behalf of the company
resulted in more timely development and implementation of the P2 program. Pollution
prevention was a success at the mill, in part, because management was willing to com-
mit the necessary resources to develop the program. While the implementation of P2
projects identified in the assessment did require capital investments from the company,
the initial investments for the projects have been recovered through annual cost
savings.
Twenty-two potential P2 projects were identified in the assessment process, and at
publication of this case study, 19 of these projects had been implemented by the com-
pany. Implementation and results of the projects are briefly described below. The proj-
ects are sorted into various groups by type of project. Cost savings are indicated for
each project when available.
The cost savings presented below will vary according to market prices. In the paper-
milling business, profits and expenditures are heavily dependent on current market
prices of paper fiber. The mill purchases predominantly waste fiber, which ranges from
$200 to $400 per ton, and at time of publication, was around $250 per ton.
The paper machine improvement projects represent the largest savings for the com-
pany from P2 projects. These projects alone have improved plant yield by over 1 percent.
The first project involved diverting approximately 3.6 tons per day of fiber rejected by
the paper machines to the de-ink plant to be used as raw material. Formerly the fiber
was discharged to the wastewater treatment plant (WWTP). The rejected fiber generat-
ed from the four paper machine cleaners is now used as raw material instead of lost as
waste. This project saves 1300 tons per year of purchased waste fiber, for a total savings
of $325,000 annually at current fiber rates. Last year the mill saved over $500,000.
The second project involved diverting one paper machine’s electrifier reject stream
(bleed) to a Johnson screen, instead of to the WWTP. This project had a payback
period of only 4 months. The project cost approximately $30,000 to install, and saves
the company 1.08 tons per day of lost fiber (395 tons annually), for an annual savings
of $100,000 at current market value.