Hydrogen Sulfide (H2S) Reduction & Corrosion Control
Stone Container (Pulp/Paper Mill) - Savannah Plant, is located within the city limits
of Port Wentworth, Georgia. The plant is tied in to the municipal wastewater treatment
system for the city of Port Wentworth.
The plant had been in operation for several years and complaints from the city residents
and government officials escalated continuously because of the extremely unpleasant
odors that were being emitted by the plant. Residents living near the plant began
to complain about discoloration of window blinds and shades. Many reports of headaches
and sore eyes also began to surface. A determination was made that the high levels
of Hydrogen Sulfide (H2S) being emitted by the plant, either directly into the air
via inadequate air scrubber systems, or as a result of effluent being released into
the wastewater sewer system, was the major cause of the yellowing effect on the blinds
and shades as well as the source for the offensive odors in the air which could be
associated with the high level of reported headaches and sore eyes.
The city of Port Wentworth also began to experience chronic problems with sewer line
blowouts and corrosion in the city’s sewer system began advancing at an alarming
rate. The blowouts were usually located within the vicinity of forced mains. Corrosion
was calculated as high as 30.86% annually in some locations. These problems were
being caused by crown corrosion which could be traced back to high concentration
of H2S in the sewer system. Leaching H2S into the concrete was causing rapid deterioration
of the city’s system. Again, the source of the problem was traced back to Stone Container.
In 1995, Port Wentworth government officials began relentlessly pressuring Stone
Container management to find a solution to the problems being created by the plant.
Organic Products Company, in association with ChemStone, Inc., was awarded a contract
to reduce the H2S emission and control sewer corrosion in May of 1995.
Bio10 was applied into the sewer system via metering pumps at strategic locations
on the Stone Container site as well as sites located in the city. Levels of initial
application were determined by the H2S levels and the maximum daily effluent flow
rate at the site. The metering stations were located “up-line” from problem areas
where unacceptable levels of hydrogen sulfide were being emitted.
For example, one lift station in the plant was consistently generating H2S reading
above 50 PPM. The maximum daily flow rate at this lift station was estimated at slightly
over 1 million gallons per day. The metering station for treatment of this lift station
was located approximately 200 yards “up-line” from the lift station at a manhole.
The H2S reading the day before treatment began was 62 PPM. Bio10 was applied at a
rate of 50 PPM of the maximum daily flow rate for the first day of treatment. The
H2S reading the following day were 12 PPM at the station. The application of Bio10
was then reduced daily until the final daily “maintenance” application reached 12
PPM, or 12 gallons per day. A total of four metering stations were eventually set
up at the plant and in the city.
Bio10 was also injected into the circulation water of the air scrubber system at
the plant. The daily application was set at 25 PPM. Tests in the gas stream showed
a reduction of hydrogen sulfide by 76%.
Corrosion tests were conducted at ten selected sites in the sewer system over a three-year
period. The introduction of Bio10 over the three-year period produced dramatic improvements
in corrosion levels. By greatly reducing the H2S in the system, the Bio10 had also
virtually eliminated the crown corrosion caused by leaching H2S. Over the three-year
test period, corrosion levels at the ten sites were reduced by an average of 87.5%,
from 19.2% annually before treatment to 2.4% annually at the end of the test period.
Over the course of this three year study, the Bio10 produced dramatic improvements
in the air quality at the Stone Container Plant, as well as the air quality in the
city of Port Wentworth. Complaints from the city’s residents and government officials
ceased. The expensive repairs to city sewer system were greatly reduced. The fragile
relationship between the Stone Container Plant and the City of Port Wentworth was