Design for Joint Treatment of Municipal and
Papermill Waste at Lynchburg, Virginia
WILLIAM H. CLINGENPEEL, Sanitary Engineer
MAYNARD K. JONES, Sanitary Engineer
Wiley and Wilson Engineers, Inc.
Lynchburg, Virginia 24501
INTRODUCTION
In 1969, as the City of Lynchburg, Virginia began planning to upgrade its existing
primary treatment facility to secondary treatment, they were approached by the State
Water Control Board and requested to consider joint treatment with the Mead
Corporation's Paperboard Plant. In complying with this request, the investigation of joint
treatment of pulp and paper wastes with municipal waste involved the following: 1) a close
evaluation of the existing Lynchburg treatment facilities, 2) a study of the Mead
Corporation's waste sources and characteristics, 3) an investigation of joint treatment
results elsewhere, 4) a study of combined Mead and Lynchburg waste treatability, 5) the
development of a joint treatment process concept, and 6) design of the joint treatment
facility.
EXISTING LYNCHBURG TREATMENT FACILITY
The present Lynchburg Waste Treatment Facility consists of a primary treatment
plant designed for an average flow of 11 MGD with considerations for expansion to 22
MGD.
Waste enters the facility through a 60-inch interceptor at a present rate of
approximately 9 MGD. It flows through a pretreatment area for screening and grit removal
and then into a wet well in the control building for pumping through a Parshall metering
flume into two primary clarifiers. Primary effluent flows to a chlorine contact tank and is
discharged through an outfall to the James River. Sludge is treated in anaerobic digesters,
dewatered on a vacuum filter in the control building, and disposed of in land fills.
To achieve adequate joint municipal-industrial treatment in this plant, secondary
treatment would be required. To provide adequate capacity for The Mead Corporation's
waste, as well as allowing for the expected growth of the Lynchburg area, the total plant
capacity would be increased from 11 to 22 MGD.
THE MEAD CORPORATION'S PROCESS AND WASTE CHARACTERISTICS
The Mead Corporation manufactures paper board using 55 percent recycled paper and
45 percent pulping of hardwood. The pulping process is an ammonia-based sulfite process
from which the pulp mill black liquors are evaporated and incinerated in the boilers as a
pollution control measure. Even so, discharges from the pulp mill are high and, combined
with discharges from the paper mill, exhibit the characteristics shown in Table I under
Alternate "A" Present Mead Waste.
Initially, the Mead Corporation felt it had three alternatives: 1) continue on the present
course, 2) tighten up the process in plant by recycling process where possible, or 3) eliminate
pulping and go to complete recycling of waste paper as well as recycling water where
possible. Projected waste characteristics of the latter two possibilities are also shown under
Alternates "B" and "C" respectively in Table I.
In actuality, two decisions were made. Initially, The Mead Corporation decided to
recycle water where possible, and waste treatability studies were conducted on composites
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