Green Bay Metropolitan Sewerage District (GBMSD)
Green Bay, Wisconsin
The Green Bay Metropolitan Sewerage District (GBMSD) is a public utility, established in 1931,
that reclaims 38 million gallons of wastewater per day at two treatment facilities in Green Bay
and De Pere, WI. Its service area covers 285 square miles and serves more than 219,000 people.
GBMSD’s mission is to promote public health and welfare through the collection, treatment, and
reclamation of wastewater, while assessing stable, competitive rates. In conjunction with others,
the organization will encourage pollution prevention and support programs to help ensure that
water contaminated by human activity is returned clean to the environment. GBMSD conducts
its business using a sustainable approach within the social, environmental, and economical
values of our customers and stakeholders.
GBMSD initiated the development of a Solids Management Plan in 2008 to address aging solids
handling facilities and the solids loadings from recently acquired De Pere Facility. The existing
solids processing system consists of belt press dewatering followed by multiple hearth
incineration. The solids system is located at the Green Bay Facility. Solids from the De Pere
Facility are transferred by pipeline to the Green Bay Facility for processing. The solids system
was constructed in the 1970s and is reaching the end of its useful life. The multiple hearth
incineration process is now considered an outdated technology. Current incineration technology
uses fluidized beds, which consume less fuel and lower air emissions.
The solids management planning effort was undertaken to develop a long-term plan for handling,
processing, and disposing of solids. The plan included a comprehensive evaluation of numerous
solids management technologies and approaches. This paper describes the process used to
develop the plan, the alternatives that were considered, the alternatives evaluation process, and
the preferred solids management alternative.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Sanitary Sewer, Stormwater, Waste Water Treatment | Tags: Environmental Impact, Minimized Life-Cycle Cost, Plant Sustainability, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
DC Water and Sewer Authority (DC Water)
Washington, DC
The DC Water and Sewer Authority (DC Water) is implementing new sludge and biosolids
processing facilites at the 1.4 million cubic meters/day (370 million gallons per day [mgd]) Blue
Plains Advanced Wastewater Treatment Plant (AWTP) in Washington D.C. The program
involves thermal hydrolysis (TH) followed by anaerobic digsetion and includes a major
cogeneration facility to provide electric power for the treatment plant and steam for the TH
process.
Decision and development criteria for DC Water’s biosolids program have evolved over recent
years and now include a broad range of factors with strong emphasis on sustainability criteria. A
major link between high-performance digestion and renewable energy production has been
forged. Key criteria for decision-making now include renewable power and energy production,
climate change issues, biosolids product quality, digestion performance, and site efficiency, as
well as capital constraints and economics.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Waste Water Treatment | Tags: Biosolids Minimization, Economic Benefits, Energy Management, Improved Digestion Performance, Plant Sustainability, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
Pine Creek WWTP
City of Calgary, Alberta (Canada)
The 100 ML/d Pine Creek WWTP is a state-of-the-art BNR facility that serves the City of
Calgary, Alberta. A delay in the construction of the primary sludge fermenters allowed a
comparison of the performance of the BNR process with and without fermentation for
extended periods of time, and facilitated a life-cycle cost analysis in which the cost of
primary sludge fermentation was compared with alternative forms of primary sludge
thickening and meeting the effluent total P limit by chemical addition. Data from the first 20
months of plant operation indicated that, with primary sludge fermentation, the plant is
capable of reliably meeting its stringent effluent total P target of <0.3 mg/L. Without
fermentation, the plant required the in-plant addition for approximately 50 mg/L of alum to
meet this same effluent quality standard. The life-cycle cost comparison between primary
sludge fermentation and enhanced biological phosphorus removal (EBPR), and two
alternative forms of primary sludge thickening and chemical P removal, indicated that
primary sludge fermentation is a cost-effective method of reliably meeting a stringent
effluent total P standard. Using a 20-year net present value (NPV) analysis, primary sludge
fermentation was found to be approximately 8 percent cheaper than mechanical primary
sludge thickening and chemical P removal, and 22 percent cheaper than gravity thickening of
primary sludge and chemical P removal.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Waste Water Treatment | Tags: Biological Nutrient Removal, Phosphorus Removal, Sludge Handling | No Comments »
Humber Treatment Plant (HTP)
Toronto, Ontario (Canada)
The Humber Treatment Plant (HTP) was experiencing severe settling problems. An opportunity
to improve the performance of the HTP was seized by the plant’s Senior Engineer by developing
and implementing a program of repair, continuous assessment, analysis, and tuning to ensure
optimal operation of the aging infrastructure. Through the strategic utilization of existing inhouse
expertise and resources, a new benchmark of excellence, serving the community through
improved and consistent effluent quality with accompanying odour reductions, was established.
This achievement was accomplished paradoxically using less energy and chemicals, thus,
significantly reducing the Humber’s environmental footprint. The direct delivery of these
services by City staff, while further enhancing in-house knowledge, skill, and stewardship,
eliminated the delays associated with project delivery using external contractors and made it
possible to reap the immediate rewards. The monetary benefits to the City are savings in
operating costs of $550,000 per year and capital savings of $6,000,000.
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Posted: May 20th, 2011 | Filed under: 500K-1M, Waste Water Treatment | Tags: Capital Savings, Decreased Energy Consumption, Improved Plant Sustainability, Operating Cost Savings, Reduced Carbon Footprint, Reduced Odor Problems | No Comments »
Various WWTP's
Switzerland
Aeration consumes about 60% of the total energy of a WWTP and therefore makes up for a
major part of its carbon footprint. Introducing advanced process control can help plants to reduce
their carbon footprint and at the same time improve effluent quality through making available
unused capacity for denitrification, if the ammonia concentration is below a certain set-point.
Measuring and control concepts are a cost-saving alternative to the extension of reactor volume.
However, they also involve the risk of violation of the effluent limits due to measuring errors,
unsuitable control concepts or inadequate implementation of the measuring and control system.
Dynamic simulation is a suitable tool to analyze the plant and to design tailored measuring and
control systems.
During this work, extensive data collection, modeling and full-scale implementation of aeration
control algorithms were carried out at three conventional activated sludge plants with fixed predenitrification
and nitrification reactor zones. Full-scale energy savings in the range of 16-20 %
could be achieved together with an increase of total nitrogen removal of 40%.
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Posted: May 20th, 2011 | Filed under: <50K, 100K-500K, 500K-1M, Waste Water Treatment | Tags: Ammonia Control, Cost Savings, Energy Savings, Environmental Impact, Plant Sustainability, Reduced Aeration, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
Little Rock Wastewater (LRW)
Little Rock, Arkansas
This paper reports on the use of a two cell 30-million-gallon (MG) equalization basin and diesel
engine-driven pump station as a means of mitigating sanitary sewer overflows (SSOs). The
ultimate capacity of the pump station, which utilizes vertical turbine solids handling pumps
(VTSH) arranged in a self-cleaning trench-style wet well, is 68 million gallons per day (MGD).
Configuring the pump station with diesel engine-driven pumps provided a 20-year, $1 million
present worth savings in comparison to a conventional electrical motor driven pump station
arrangement. The use of diesel engine-driven pumps eliminated the peak electrical usage of 450-
horsepower (HP) electrical motors, as well as the need for variable frequency drives and
redundant power generation needs during electrical outage time periods. A supplemental 150-
kilowatt (kW) generator was installed to provide emergency power needs for SCADA, seal water
systems, influent screen, and a 50-HP maintenance pump for wetwell cleaning.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Sanitary Sewer, Stormwater, Waste Water Treatment | Tags: Cost Savings, Decreased SSO Volume, Energy Savings, Improved Plant Efficiency | No Comments »
Michelson Water Recycling Plant (MWRP)
Irvine, California
Recycled water corrosivity control is an important consideration in the design and operation of
wastewater treatment plants and recycled water distribution systems. Even mild corrosivity can
have significant long-term impacts on equipment and pipelines. Corrosivity control involves
adjustments to water chemistry (pH, alkalinity, hardness, etc.), but how adjustments are
implemented can vary based on existing treatment processes. For the Michelson Water
Recycling Plant, corrosivity control was achieved by modifying an existing process rather than
adding a new one. This paper discusses the investigation and evaluation of several treatment
alternatives for corrosivity control. The study resulted in replacing chlorine gas disinfection with
sodium hypochlorite disinfection, which offered the additional advantage of addressing
operational, regulatory, and safety concerns associated with the use and storage of gaseous
chlorine. The study highlights the connection between disinfection and corrosivity, an important
consideration for other agencies starting water recycling programs to meet increasing water
demand.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Stormwater, Waste Water Treatment, Water Treatment | Tags: Corrosion Control, Cost Savings, Improved Plant Health/Safety, Improved Plant Reliability | No Comments »
Back River Wastewater Treatment Plant
Baltimore, Maryland
The City of Baltimore has investigated various alternatives to meet the future effluent total
nitrogen goal of 3 mg/L and current stringent total phosphorous limit of 0.2 mg/L at its Back
River Wastewater Treatment Plant. The selected technology, deep-bed downflow denitrification
filter, allows for both nitrogen reduction and partial solids removal. In an effort to confirm the
design criteria, a small-scale filter pilot study was undertaken between January and July, 2009.
As a result of comprehensive nutrient reduction initiatives for the Chesapeake Bay watershed,
the demand for supplemental carbon sources such as methanol is growing and there has been a
great deal of interest in the practicability of utilizing alternative carbon sources. Hence, it was
also important to evaluate use of alternative carbon sources in order to (1) establish the carbon
requirements specific to each substrate (for design considerations) and (2) evaluate operational
conditions. This pilot study was segmented into three phases: methanol (as control), ethanol and
MicroC™-glycerin. The results of this study suggest that, under warm temperature periods
(~20C), the effluent nitrate (NOx-N) concentration of approximately 0.5 mg/L was achieved
with all the carbon sources at or below the average nitrate loading rate of 38 lb/1000 ft3/day (0.6
kg/m3/d). Even with higher loading rates, effluent quality did not degrade significantly and
remained < 1 mg/L most of the time. Observed COD/NOx-N ratios were ~5.5 (ethanol) and ~7.0
(glycerin). Some operational differences were noted between methanol, ethanol and glycerin.
Glycerin appeared to promote the growth of an unusual biofilm on all of the piping surfaces with
which it came in contact, and had noticeably higher yield that led to an increase in backwash
frequency when compared to ethanol. In summary, denitrification performance with both of the
tested alternative carbon sources met removal requirements. This testing also confirmed that
excess available carbon was needed in the filter effluent to maintain performance.
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Posted: May 20th, 2011 | Filed under: 500K-1M, Waste Water Treatment | Tags: Alternative Carbon Testing, Partial Solids Removal, Phosphorus Reduction, Reduced Nitrogen | No Comments »
Miami-Dade Water and Sewer Department
Miami, Florida
Difficult times require an extra effort when it comes to communication. With all of the talk
about layoffs, budget cuts and salary reductions, utilities face an uphill battle against the internal
“rumor mill”, declining morale during the current economic downturn, and external pressures to
do more with less. A well-developed communication strategy is one key to sustaining
performance in the face of these challenges.
The Water Distribution and Transmission Division of the Miami-Dade Water and Sewer
Department is meeting these challenges “head-on” with an aggressive communication program
that has been developed and refined over a number of years. This presentation will highlight that
program from the perspectives of the Division Chief, managers and supervisors, and employees.
Extensive interviews at various levels of the organization identified key communication
strategies and tactics that are helping this agency maintain a high level of performance through
the most significant economic crisis the US has faced since the Great Depression. These
strategies and tactics will be discussed in detail and results will be presented as a “business case”
for optimizing communication during challenging times.
Focus of Study and Results:
This presentation will include discussion in communication topic areas including:
1. General overview of communication strategies and tactics
2. Types, frequencies, and styles for effective communication
3. Directional communication – up, down, and across the organization
4. Formal and informal communication methods and tools
5. Strengths and weaknesses of various communication approaches
6. Value and results from effective communication programs
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Posted: May 20th, 2011 | Filed under: >1M, Sanitary Sewer, Stormwater, Waste Water Treatment, Water Treatment | Tags: Effective Communication, Improved Customer Relations, Improved Plant Efficiency, Improved Work Morale | No Comments »
Werribee Treatment Plant
Melbourne, Australia
Waste Stabilization Ponds are used extensively for sewage treatment in moderate and
tropical climates, and represent one of the most cost-effective, reliable and easily
operated processes for the treating domestic and industrial wastes. One of the biggest
problems associated with pond treatment, however, is the high algae concentrations in the
effluent. In many cases algae are not a desirable by-product and are themselves a source
of secondary pollution, rich in carbonaceous and nitrogenous algae matter. This puts an
environmental strain on the receiving waters. One of the recently improved ways to
control algae is to use trickling filters with a heterotrophic biofilm created by augmenting
readily available sustenance to the filter media. This paper examines some of the hybrid
facilities being used that combine existing stabilization ponds with trickling filters or
activated sludge for enhanced biological degradation and polishing of the final effluent.
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Posted: May 20th, 2011 | Filed under: >1M, Waste Water Treatment | Tags: Algae Removal, Improved Plant Effluent, Improved Water Quality, Plant Sustainability, Reduced Carbon Footprint, Reduced Nitrogen Load, Reduced Nutrients, Reduced Solids | No Comments »