ENVIRONMENTALLY BALANCED AND RESOURCE-OPTIMIZED
KRAFT PULP AND PAPER MILL COMPLEX
Ram N. Tewari, Graduate Assistant
Nelson L. Nemerow, Professor
Department of Civil Engineering
University of Miami
Coral Gables, Florida 33124
The use of paper and its products has been growing rapidly and consistently all over the
world. The United States, world's largest producer and consumer of forest products, also
dominates world production (35%) and consumption of paper and its products [ 1 ].
A total of 706 operating mills of the United States have the capacity to produce about
0.021 million metric tons per day of paper and its products [1]. Paper products annual
consumption was 64.3 million metric tons, i.e., 639 lb by each American, the highest in
the world [2].
The pulp and paper industry is the fifth largest in the U.S. economy and ranks third
in its expansion. Despite the relative weight of finished product, pulp and paper constitute
one of the major tonnage products in the United States and it may soon challenge the
output of the steel industry in annual production.
This industry is expected to grow at a fairly rapid rate up to 1985, even after the economic recession caused due to oil price increases, inflation and money strictness. It is anticipated that the growth of the industry will closely parallel the gross national product.
Between 1979 and 1983 growth of newsprint is estimated to increase 8.6% while demand
for improved grades are estimated to increase 19% [ 1 ].
The distinguishing characteristics of the pulp and paper industry are high level of capital
investment, relatively low marginal profit, numerous production operations, considerable
utilization and consumption of utilities and land resources and large wastes production.
The industry requires as much as $1.50 of capital investment for each dollar of annual
sales and its return on investment has been only 7-8% [3].
Because of its capital-intensive nature and to meet ever increasing demand for its products, the trend had been towards establishing larger mills. A 1000-ton/day plant is an average
size for effective and economic pulping in these days. Therefore, considerable air, water
and land resources are utilized and affected by modern paper mills.
The production of paper and its products involves several standard manufacturing processes including raw material preparation, pulping, bleaching and product making. In these
operations water is used as a medium of transport, a cleaning agent and as a solvent or
mixer. Important secondary uses of water are for cooling, boiler feed, vacuum seals, and
housekeeping purposes. Hence, pulp and paper manufacture by its very nature is a water-
intensive industry.
Annual water usage by the pulp and paper industry in the United States is approximately two trillion gallons and seven billion of wastewater is discharged per day. Fully
bleached integrated pulp (kraft) and paper mill's water usage is about 20,000-40,000 gal/
ton of product [4|.
Apart from water, other important requirements in the manufacturing processes of
the industry are raw material (wood), chemicals and energy. The energy consumption
is about 2.2% of the total national consumption [5]. Costs are escalating dramatically
and economic pressures are compelling to either minimize consumption or to find alternatives.
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