Bio-Treatment
Design for Pulp-Paper Wastes
WILLIAM D. RICE, Director of Research
P. H. Glatfelter Company
Spring Grove, Pennsylvania
and
ROY F. WESTON, President
Roy F. Weston, Inc.
Newton Square, Pennsylvania
The P. H. Glatfelter Company manufactures high grade printing and specialty papers from wood pulp. The company mill is located in the borough
of Spring Grove on the banks of Codorus Creek. The mill takes its water supply from an impounding reservoir on Codorous Creek. Treated wastes are
discharged into the creek Delow the impounding dam.
The Codorus Creek watershed area above the Company dam is 74. 3 sq
miles. The mean annual flow is 50 MGD. Under extreme dry weather conditions the waste water discharges from the P. H. Glatfelter Company plant
constitute the entire stream flow. These low flow stream conditions have
occurred more frequently in recent years.
In an effort to improve stream conditions, the company has operated
primary waste treatment facilities since 1951. These facilities consist of a
pumping station, sedimentation tanks and sludge accumulation and drying
ponds.
In addition to the construction and operation of primary treatment facilities, the company has carried on considerable in-plant work to reduce fibre
losses, to contain BOD pollution and to eliminate various alkaline and solids
materials.
In the pulp mill, enlargements and additions to recovery equipment and
improvements in methods did much to further tighten those systems and reduce
to a bare minimum wastes from the department. Old horizontal evaporators
were replaced by a modern vertical septuple effect evaporator system to more
effectively concentrate the spent or black liquor before burning. Additional
rotary furnaces were installed to provide ample capacity for burning all the
black liquor. Improvements were achieved in the causticizing and lime recovery systems as a result of intensive study and perseverance. As a result of
these gains in the pulp mill, reductions of up to 50 per cent in BOD loading
in the total mill effluent were attained.
In the de-inking plant, revisions were obtained in washing and other
operations which resulted in significant reduction in fiber losses. These revisions afforded economic advantages and lessened stream pollution.
In the paper mill much time and effort spent on machine save-all and
overall water systems contributed marked reductions in machine stock and
water losses. Floatation savealls on the two large machines were enlarged to
provide needed additional margins of efficiency. Improved savealls were installed in other machine systems in place of outdated Deckers and settling
tanks. In a number of cases overall water systems were completely rearranged or rebuilt to enable maximum closure and retention of paper making
materials.
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