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.
Metric Used:
Posted: May 20th, 2011 | Filed under: 100K-500K, Waste Water Treatment | Tags: Biological Nutrient Removal, Phosphorus Removal, Sludge Handling | 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.
Metric Used:
Posted: May 20th, 2011 | Filed under: 500K-1M, Waste Water Treatment | Tags: Alternative Carbon Testing, Partial Solids Removal, Phosphorus Reduction, Reduced Nitrogen | No Comments »
Large food manufacturing company has facilities to produce their well known brand
name dairy based products in rural Indiana. As is commonly case with dairy wastewater,
significant amount of proteins, sugars, oil and some suspended solids are present.
Company installed membrane bioreactor (MBR) System to treat such wastewater for
possible reuse.
The MBR performed poorly due to membrane fouling. Manufacturer suggested that in
addition to screen other primary pretreatment is needed to reduce FOG and organic TSS
as low as possible prior to MBR treatment. Classical DAF and advanced hybrid
centrifugal – dissolved air flotation (GEM) were pilot tested. Both systems performed
well, but GEM removed FOG and TSS to lower amount and produced drier sludge. The
full scale GEM System has been installed in June 2010. Dual high molecular weight
flocculants and GEM flotation remove TSS below 50 mg/l, FOG below 2 mg/l and
produce sludge with 20% solids. Data are currently collected to evaluate how such
pretreatment improves operation of the MBR.
Metric Used:
Posted: May 20th, 2011 | Filed under: Waste Water Treatment | Tags: Improved MBR Operation, Improved Plant Efficiency, Optimized BOD Removal, Optimized FOG Removal, Optimized TSS Removal | No Comments »
Two clean technologies, namely, “Anaerobic hydrogen production” and “Microbial fuel cells
(MFC)”, hold great potential for producing energy from wastewater, which can provide economic
and environmental benefits. Although 1 mole of glucose can theoretically produce 12 moles of
hydrogen, the experimental hydrogen yields obtained are only 0.9-2.0 moles [1, 2]. The liquid
fermentation products in the anaerobic treated wastewater cause the high chemical oxygen demand
(COD) in the effluent. It is desired to further treat these liquid products using MFCs to improve
effluent quality and harvest energy. By converting the chemical energy stored in wastewater to
electricity, MFCs can substantially reduce the operational cost in wastewater treatment plants [3].
Due to the limitation of current technologies, the operation of hydrogen bioproduction and MFC
individually in wastewater treatment is not suitable. Although hydrogen production is a good energy
resource, the COD removal efficiency remains low. On the other hand, MFC could achieve high
COD removal efficiency, but the power densities are low. In this study, the HPB and SCMFC were,
for the first time, operated in series to increase overall energy recovery from wastewater and enhance
COD removal efficiency for potential reclamation.
Metric Used:
Posted: May 20th, 2011 | Filed under: Waste Water Treatment | Tags: Cost Savings, Energy Savings, Enhanced COD Removal Efficiency, Environmental Impact, Plant Sustainability, Reduced Carbon Footprint | 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%.
Metric Used:
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 »
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.
Metric Used:
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 »
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.
Metric Used:
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 »
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
Metric Used:
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 »
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.
Metric Used:
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 »
Dallas Water Utilities (DWU)
Dallas, Texas
Dallas Water Utilities (DWU) has identified multiple projects within their wastewater treatment
plants (WWTPs) to support the Green Dallas Initiative for energy conservation and
sustainability. In 2010, a new co-generation facility at the Southside Wastewater Treatment Plant
(SWWTP) will be brought on-line. This facility will utilize digester gas for electricity
production. As part of the Green Dallas Initiative, and to optimize the co-generation facility, the
feasibility of adding high strength wastes to the anaerobic digesters at SWWTP to increase the
digester gas production was evaluated.
Metric Used:
Posted: May 20th, 2011 | Filed under: 100K-500K, Stormwater, Waste Water Treatment, Water Treatment | Tags: Cost Savings, Electricity Production, Environmental Impact, Improved Plant Sustainability, Increased Digester Gas, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »