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2017

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Articles 61 - 90 of 270

Full-Text Articles in Environmental Engineering

Laboratory Characterization Of Unsteady Boundary Layers, Umair Sarwar, Cary Troy Aug 2017

Laboratory Characterization Of Unsteady Boundary Layers, Umair Sarwar, Cary Troy

The Summer Undergraduate Research Fellowship (SURF) Symposium

The study of waves and their effects on mean flow and turbulence in natural water bodies is an important issue for applications in aquatic biology, coastal engineering, sediment transport and hydrodynamic of the lake. These waves result in the generation of an oscillatory (Stokes) boundary layer near the bottom of the water column. The goal of this study was to conduct various experiments that will be used to characterize the turbulence in unsteady boundary layers and help understand the relation between various flow variables (e.g. wave amplitude, frequency, water depth, turbulent kinetic energy, etc.). Using the research facilities provided, three …


Electrochemical Removal Of Lead In Water With Multi-Wall Carbon Nanotube Filters, Benjamin M. Stryker, Sol Park, Zhi Zhou Aug 2017

Electrochemical Removal Of Lead In Water With Multi-Wall Carbon Nanotube Filters, Benjamin M. Stryker, Sol Park, Zhi Zhou

The Summer Undergraduate Research Fellowship (SURF) Symposium

Heavy metals, such as lead, are highly toxic and typical removal techniques are costly for household applications; causing serious public health risks and economic burdens. Previous studies using electrochemical filtration showed that singe-wall carbon nanotube membranes (SWCNTs) were effective at removing lead, but the use of less expensive multi-walled carbon nanotubes (MWCNTs) has not been fully explored. Therefore, there is a critical need to determine if MWCNTs are cost-effective for the removal of lead in water. The removal efficiency of lead(II) ions in an aqueous solution was evaluated in a flow-through filtration system over 50 minutes at 1.5 mL/min. Calcium …


Improving The Accuracy For The Long-Term Hydrologic Impact Assessment (L-Thia) Model, Anqi Zhang, Lawrence Theller, Bernard A. Engel Aug 2017

Improving The Accuracy For The Long-Term Hydrologic Impact Assessment (L-Thia) Model, Anqi Zhang, Lawrence Theller, Bernard A. Engel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Urbanization increases runoff by changing land use types from less impervious to impervious covers. Improving the accuracy of a runoff assessment model, the Long-Term Hydrologic Impact Assessment (L-THIA) Model, can help us to better evaluate the potential uses of Low Impact Development (LID) practices aimed at reducing runoff, as well as to identify appropriate runoff and water quality mitigation methods. Several versions of the model have been built over time, and inconsistencies have been introduced between the models. To improve the accuracy and consistency of the model, the equations and parameters (primarily curve numbers in the case of this model) …


Technology To Manufacture Oriented Pvc (Pvc-O) Pipes, Purdue Ect Team Aug 2017

Technology To Manufacture Oriented Pvc (Pvc-O) Pipes, Purdue Ect Team

ECT Fact Sheets Archive

The development of Molecor´s technology, which is based on the application of a Molecular Orientation process, has delivered a significant turning point in the pipelines sector. With this technological development, the company has begun to manufacture TOM® PVC-O pipes, the most eco-friendly pipes on the market. The Molecor technology enabled eradicating many of the existing disadvantages of thermoplastic pipes.

This technology delivers a clear objective; to provide the water industry with a solution for pipes carrying pressurized water in an environmentally friendly, yet cost efficient manner. This also extends a service life compared to pipeline materials currently in use.

The …


Full-Water Column Turbulence Parameterization Of Stratified Waters In Southern Lake Michigan, Kyla A. Prendergast, Cary D. Troy, David Cannon Aug 2017

Full-Water Column Turbulence Parameterization Of Stratified Waters In Southern Lake Michigan, Kyla A. Prendergast, Cary D. Troy, David Cannon

The Summer Undergraduate Research Fellowship (SURF) Symposium

Full water column mean flow and turbulence structure was characterized at two stratified locations in Lake Michigan (a. Muskegon, MI; b. Michigan City, IN) in order to better understand the filtration potential of invasive quagga mussels. Invasive quagga mussels in Lake Michigan are filter feeders and can dramatically alter clarity as well as the biological/chemical characteristics of the water column. This filtering capacity is highly contingent on turbulence characteristics throughout the water column, which is poorly understood in the Great Lakes. Using velocity, temperature, and turbulence data collected from these locations, the structure of the water column turbulence was modeled …


Assessing The Hydraulics Of Water Heaters By Adding Fluoride As A Tracer To Inform Its Overall Effect On Water Quality, Christian A. Guerrero, William Schmidt, Antoine Aubeneau, Amisha D. Shah Aug 2017

Assessing The Hydraulics Of Water Heaters By Adding Fluoride As A Tracer To Inform Its Overall Effect On Water Quality, Christian A. Guerrero, William Schmidt, Antoine Aubeneau, Amisha D. Shah

The Summer Undergraduate Research Fellowship (SURF) Symposium

As residential water heaters are the primary source of waterborne disease outbreaks in the U.S. there is a need to better understand how they are contributing to decreased water quality in buildings. Previous work has indicated that intermittent stagnation, low disinfection residual and operation temperatures promote the growth of pathogens in water heaters. The overall effect of hydrodynamics of water heaters on these factors remains unclear. Therefore, a tracer study was performed to determine the effect of and characterize hydraulics of the typical residential water heater on water quality. Controlling temperature and flow rate, a pilot-scale hot water system (50 …


How Governmental Greenhouse Gas Science Has Been Weathered Through Time And Why It Matters, Christopher Apple Aug 2017

How Governmental Greenhouse Gas Science Has Been Weathered Through Time And Why It Matters, Christopher Apple

STAR Program Research Presentations

Global consumption of materials and energy is accelerating. The rate of plant and animal species extinction is accelerating. On a finite Earth with a growing population, current consumption cannot continue sustainably. Greenhouse gases (GHGs) tell us an important part of this story. The Global Greenhouse Gas Reference Network, managed by scientists at NOAA’s Earth System Research Laboratory, is the largest greenhouse gas analysis network in the world. It has been shaped by scientific questions, stagnant funding despite rises in research costs, and the task of understanding how the Earth system will respond to a changing climate. The Network began by …


Identifying Corrosion Zones In Coastal Regions For Metal Pipes -- A Gis Approach, Sanjay Tewari, Francis Manning Aug 2017

Identifying Corrosion Zones In Coastal Regions For Metal Pipes -- A Gis Approach, Sanjay Tewari, Francis Manning

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transportation agencies often allow metal pipes as an option for cross drains under/along roads and highways. Metal culverts can corrode over time at various rates based on their environmental conditions (e.g., corrosive nature of coastal soils, high water table and saltwater intrusion). This paper focuses on applying readily available soil data such as spatial distribution of soil types and soil characteristics (e.g., pH and conductivity) towards creating a geospatial information system (GIS) based approach to identifying corrosion zones in the coastal regions. A combination of data, obtained from field surveys provided by the Louisiana Transportation Research Center and Web Soil …


Simulation And Prediction Of The Groundwater Level In The Surrounding Area Of The Nebraska Management System Evaluation Area Site In Central Nebraska., Cesar Augusto Gomez Peña Aug 2017

Simulation And Prediction Of The Groundwater Level In The Surrounding Area Of The Nebraska Management System Evaluation Area Site In Central Nebraska., Cesar Augusto Gomez Peña

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

An efficient water budget is necessary to develop sustainable practices in irrigated lands and determine future trends. Despite a lack of detailed knowledge, climate change is found to profoundly influence groundwater resources through changes in groundwater recharge, groundwater elevation, and groundwater flow processes. Prediction of the groundwater level (GWL) under a changing climate is essential to improve agricultural management.

The goal of this research is to predict the GWL from 2056 to 2060 in the surrounding area of the MSEA. In order to achieve the target, the first research task is to develop a groundwater flow model and then simulate …


Engineering Applications Of Organic Surfactant Modified Bentonite In Sorptive Soil Barriers., Sadra Javadi Aug 2017

Engineering Applications Of Organic Surfactant Modified Bentonite In Sorptive Soil Barriers., Sadra Javadi

Electronic Theses and Dissertations

Earthen barriers such as CCLs and GCLs have been employed in geotechnical practices to provide a low permeability hydraulic barrier since long time ago. These types of barriers exhibited satisfactory performance for many applications such as landfills. The performance of low permeability barriers is based on the swelling potential of their component, which is mostly Na-bentonite, in contact with polar fluids such as water. However, the acceptable range of conductivity cannot be achieved by traditional earthen barriers when they are permeated by non-polar fluids such as gasoline. This phenomenon occurs due to the incompatibility of earthen barrier constituent with non-polar …


Cationic Surfactant Modification And Its Impact On The Engineering Behaviors Of Montmorillonite., Mohammad Ghavami Aug 2017

Cationic Surfactant Modification And Its Impact On The Engineering Behaviors Of Montmorillonite., Mohammad Ghavami

Electronic Theses and Dissertations

This study focuses on the microstructure of organoclays after organic surfactant modifications and the potential use in geoenvironmental engineering applications including waste containment in earthen barrier, rheological control agents for drilling fluid and soil stabilization. Organoclays, or clays modified by organic matters, are often synthesized by exchanging the naturally occurring interlayer inorganic cations (e.g., Na+, Ca2+) of the clay with organic cationic surfactants. In this research, montmorillonites intercalated with two quaternary ammonium surfactants, hexadecyltrimethylammonium (HDTMA+) and bis (hydrogenated tallow alkyl) dimethyl ammonium were used as the representative organo-rich, partitioning clays. The laboratory characterization techniques including XRD, TEM and …


Removal Of Nitrates From Stormwater Using Nanoclays, Rubia Siddiqi Aug 2017

Removal Of Nitrates From Stormwater Using Nanoclays, Rubia Siddiqi

Master's Theses

Creeks and rivers are often polluted as a result of stormwater runoff that carries various contaminants in to open water bodies, causing adverse environmental and health effects. Low impact development (LID) techniques are currently employed to treat this runoff prior to discharge. Nitrate, however, is not consistently removed by these LID techniques. This study analyzed the ability of several nanoclays to remove nitrate in runoff and determined the feasibility of using them as a soil supplement for LID implementation. Six different nanoclays and HCl-treated clays were compared (pre-modified trimethyl stearyl ammonium nanoclay, pre-modified dimethyl dialkyl amine nanoclay, unmodified hydrophilic bentonite, …


Rejection Of Low Molecular Weight Neutral Organics By Reverse Osmosis Membranes For Potable Reuse, Lauren N. Breitner Jul 2017

Rejection Of Low Molecular Weight Neutral Organics By Reverse Osmosis Membranes For Potable Reuse, Lauren N. Breitner

Civil Engineering ETDs

Factors such as increasing population, urbanization, and climate change have made the management of water resources a challenge for many municipalities. Water reuse, especially direct potable reuse (DPR) of treated wastewater, is increasingly seen as a potential source of water for communities facing water shortages. Due to improvements in analytical capabilities as well as concerns regarding toxicology of contaminants of emerging concern (CECs), the need for investigating the removal of CECs has become crucial for further DPR considerations. Reverse osmosis (RO) has been demonstrated to remove many CECs. Many studies, however, have investigated the removal of well-known CECs, often with …


The Fate Of Fecal Indicator Bacteria In Passive Nitrogen Reduction Systems, Michelle B. Henderson Jul 2017

The Fate Of Fecal Indicator Bacteria In Passive Nitrogen Reduction Systems, Michelle B. Henderson

USF Tampa Graduate Theses and Dissertations

The sustainability of water resources is an international and national concern. With increased human activity, water distribution on a global, regional, and local scale has been negatively impacted. Managing water resources also includes managing wastewater. A promising solution to the issues of water scarcity and distribution in the environment is the reuse of wastewater. Wastewater is produced from various sources (domestic, industrial, and commercial); however, if this water is able to be reused closer to the source of generation it could positively impact water distribution. In the United States, approximately 25% of domestic wastewater is treated in onsite wastewater treatment …


Performance Study On Evacuated Tubular Collector Coupled Solar Still In West Texas Climate, Roy Issa, Byungik Chang Jul 2017

Performance Study On Evacuated Tubular Collector Coupled Solar Still In West Texas Climate, Roy Issa, Byungik Chang

Civil Engineering Faculty Publications

Experimental study was performed on a single basin active solar distillation system augmented with a solar collector using evacuated solar tubes. Field tests were conducted over several days under the climatic conditions of West Texas to evaluate the effect evacuated solar tubes have on the daily distillate yield rate. To investigate the feasibility of the solar tubes, active and passive solar stills with and without exterior insulation were examined. The maximum daily production rate for the active distillation system using evacuated solar tubes and the passive distillation system was 3.6 and 1.4 kg/m2day, respectively. The results showed the …


Advanced Treatment Technologies For Mitigation Of Nitrogen And Off-Flavor Compounds In Onsite Wastewater Treatment And Recirculating Aquaculture Systems, Laura C. Rodriguez-Gonzalez Jul 2017

Advanced Treatment Technologies For Mitigation Of Nitrogen And Off-Flavor Compounds In Onsite Wastewater Treatment And Recirculating Aquaculture Systems, Laura C. Rodriguez-Gonzalez

USF Tampa Graduate Theses and Dissertations

Non-point sources (NPS) of pollution are non-discernable, diffuse sources of pollution that are often difficult to localize and in turn mitigate. NPS can include stormwater runoff, agricultural/aquaculture wastes and wastes from small decentralized wastewater treatment systems, such as conventional septic systems. The mitigation of these NPS is imperative to reduce their potential detrimental effects on the water environment. This dissertation addresses novel treatment technologies for the mitigation of nutrients, particularly nitrogen, in Recirculating Aquaculture Systems (RAS) and onsite wastewater treatment systems (OWTS). The removal of trace organics limiting RAS production and water reuse were also investigated.

The first question this …


Polymer-Capped Nanoparticle Transport In Granular Media Filtration: Deviation From The Colloidal Filtration Model, Ijung Kim, Tongren Zhu, Sungmin Youn, Desmond F. Lawler Jul 2017

Polymer-Capped Nanoparticle Transport In Granular Media Filtration: Deviation From The Colloidal Filtration Model, Ijung Kim, Tongren Zhu, Sungmin Youn, Desmond F. Lawler

All Engineering Faculty Research

The single-collector removal efficiency based on the colloidal filtration model is widely used to quantify deposition of nanoparticles in porous media filtration. The validity of this theory for nanoparticles, especially at filtration rates used in water treatment, was evaluated. Granular media filtration experiments were performed under widely variant physical conditions. Chemical effects were minimized by selecting spherical branched polyethylenimine capped silver nanoparticles as a positively charged nanoparticle to avoid electrostatic repulsion with the negatively charged silica filter media. The model and experimental results agreed well for 50 and 100 nm particles, but 10 nm particles were removed to a lesser …


A Statistical Investigation Of Lower Columbia River Water Temperature, 1915-2003, Corina Christina Mae Overman Jul 2017

A Statistical Investigation Of Lower Columbia River Water Temperature, 1915-2003, Corina Christina Mae Overman

Civil and Environmental Engineering Undergraduate Honors Theses

The Columbia River is home to anadromous salmon populations that migrate upriver every year to spawn. These fish require cool water temperatures (Tw) to survive. In recent years, high summer Tw in the Columbia River has caused increased mortality of salmon. Different possible explanations for increased Tw include climate change, deforestation, and decreased summertime streamflow (Q) due to dams. In this study, robust linear regression models of Tw based on air temperature (Ta) and Q were developed to examine the change in Tw over time. The data was …


Evaluation Of The Fertilization Properties Of Algal Biomass And Assessment Of Koh-Induced Flocculation Of Pw95 Algal Cells, Olakunle Ogunsakin Jul 2017

Evaluation Of The Fertilization Properties Of Algal Biomass And Assessment Of Koh-Induced Flocculation Of Pw95 Algal Cells, Olakunle Ogunsakin

Graduate Theses & Non-Theses

Microalgae from the Coal Bed Methane (CBM) ponds of the Powder River Basin (PRB) in Southeastern Montana have the potential to be utilized as fertilizer for use on the economically important plants of Montana. Three very important economic field crops of Montana (winter wheat - Triticum aestivum, potato - Solanum tuberosum, and flax - Linum usitatissimum) were used for the fertilization experiments. Isolates of unicellular green algae - PW95 (sequenced as Neospongiococcum sp.) from the CBM ponds, and blue-green microalgae – Cyanobacteria (Anabaena Cylindrica) were cultured in the laboratory and the cells were concentrated using gravity sedimentation. Nutrient analysis of …


Inertization, Utilization, And Safe Disposal Of Incineration Residues, Anil Mehrotra Jul 2017

Inertization, Utilization, And Safe Disposal Of Incineration Residues, Anil Mehrotra

Civil & Environmental Engineering Projects for D. Eng. Degree

Combustion of coal or Municipal Solid Waste (MSW) caused air pollution and produces solid residues which contain high levels of toxic elements. The toxic characteristics of residues generated from combustion of MSW in waste-to-energy plants are strictly controlled by Federal and State Waste Management Regulations. According to Resource Conservation and Recovery Act (RCRA), residue generated from combustion of MSW is considered hazardous and must be tested according to EPA Toxic Characteristics Leaching Procedure (TCLP) Method 1311 and suitably treated for its safe disposal to landfills. Experiments with various treatment chemicals as primary independent variable had earlier been conducted by several …


Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong Jul 2017

Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong

Master's Theses (2009 -)

Coal is a significant source of energy in today’s world and many studies have been conducted in order to better understand and optimize its use. To address greenhouse effects associated with coal combustion, cleaner methods for harnessing its energy are being explored. One such method is gasification, a process which converts coal into syngas, a mixture consisting primarily of H2 and CO. Syngas can be used to generate electricity or to produce hydrocarbons that can be used as fuels. To better understand and optimize the process, simulations can be used to study the gasification of individual porous char particles that …


An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou Jul 2017

An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou

Master's Theses (2009 -)

Arsenic is a Group 1 carcinogen as there is abundant research to support that ingestion of arsenic in drinking water and food can lead to liver, lung, kidney, or bladder cancer in humans. The recommend World Health Organization (WHO) arsenic standard in drinking water is 10 µg/L, while the Environmental Protection Agency's (EPA) Maximum Contaminant Level (MCL) of arsenic in drinking water is 10 µg/L. Globally, at least 40 million people face more than 10 µg/L arsenic contamination in their drinking water. As(III) (trivalent state, such as arsenite), and As(V) (pentavalent state, such as arsenates) are the dominant arsenic forms …


A Comparative Study Of The Effects Of External Selection On Settleability And Formation Of Aerobic Granular Sludge, Tyler A. Brickles Jul 2017

A Comparative Study Of The Effects Of External Selection On Settleability And Formation Of Aerobic Granular Sludge, Tyler A. Brickles

Civil & Environmental Engineering Theses & Dissertations

Aerobic granular sludge (AGS) has shown much promise in the advancement of the wastewater treatment industry. AGS has been studied intensely since the early 1990’s due to highly desirable characteristics of nutrient removal efficiency, low footprint, and abnormally faster settling rates than conventional activated sludge. With the exception of a few on-going research projects, all AGS systems have been studied and implemented through the use of sequencing batch reactors (SBR). Recently, a novel approach to developing AGS and improving settling characteristics of activated sludge within conventional activated sludge (CAS) processes has being attempted through the use of external selection.

Activated …


Investigation And Analysis Of The Fluctuating Brominated To Total Trihalomethane Ratio In The Virginia Beach Distribution System, Christopher Steven Mihalkovic Jul 2017

Investigation And Analysis Of The Fluctuating Brominated To Total Trihalomethane Ratio In The Virginia Beach Distribution System, Christopher Steven Mihalkovic

Civil & Environmental Engineering Theses & Dissertations

An increasing trend in the brominated-trihalomethane to total-trihalomethane concentration ratio from 2001 to 2016 in the Virginia Beach water distribution system was established and investigated. This study aimed at identifying factors contributing to fluctuations in trihalomethane speciation in finished water. Reservoir management practices, treatment processes, and source water conditions were examined to quantitatively and qualitatively discern the impact of their variations on finished water THM speciation. Data on water quality constituents and parameters from the Moore’s Bridges Treatment Facility and within the Virginia Beach distribution system were examined to interpret spatial and temporal relationships with trihalomethane concentrations using established research …


Simulated Dynamics Of Soil Water And Pore Vapor In A Semi-Arid Sandy Ecosystem, Shohreh Pedram Jul 2017

Simulated Dynamics Of Soil Water And Pore Vapor In A Semi-Arid Sandy Ecosystem, Shohreh Pedram

Civil & Environmental Engineering Theses & Dissertations

Understanding dynamics of soil water content (SWC) and pore air relative humidity (RHpa), as influenced by wetting-drying cycles, is crucial for sustaining fragile ecosystems of desert lands across the world and needed for improving the prediction accuracy of global climate change. However, to date, such an understanding is still incomplete. The objective of this dissertation was to examine such dynamics at a typical desert site within the Horqin Sandy Land, located in Mongolian Plateau of north China. The examination was done by using a HYDRUS-1D computer simulation model and the continuous sensor-based soil water data for two calendar years. HYDRUS-1D …


Benchmarking The Energy Intensity Of Small Nebraska Wastewater Treatment Plants, Steven M. Hanna Jul 2017

Benchmarking The Energy Intensity Of Small Nebraska Wastewater Treatment Plants, Steven M. Hanna

Department of Environmental Engineering: Theses and Other Student Research

To help small communities improve the energy efficiency of their wastewater treatment plants, this study created energy benchmarking models for small wastewater plants serving populations of 10,000 or less and having average flows less than 1.5 million gallons per day (MGD). The purpose of these models is to allow comparisons among plants of similar type and size, identify what factors most significantly impact energy usage, and predict potential savings from changes in key plant characteristics.

Energy usage and plant data from 83 small, mechanical wastewater plants in Nebraska were collected and used to create energy benchmarking models. Data obtained from …


Streambank Erosion Mapping On The Nottoway River Using Gps-Based Above-Water Video, Emine Fidan Jun 2017

Streambank Erosion Mapping On The Nottoway River Using Gps-Based Above-Water Video, Emine Fidan

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

This project concerns the development of streambank erosion maps on military installations utilizing GPS-based above-water video mapping and image georeferencing techniques. The river mapped was the Nottoway River at the Fort Pickett military installation on October 10-11, 2015. Kayak-mounted above-water cameras were utilized to capture georeferenced images of streambank erosion. These GIS-based erosion classifications were utilized to develop erosion maps for determining streambank erosion conditions along the river. Areas of high erosion were identified as about two percent of the river (2167 ft. of streambank length). These maps allow for the opportunity to revisit the sites to determine changes in …


Carbon And Nutrient Balances In Microalgal Bioenergy System, Eunyoung Lee Jun 2017

Carbon And Nutrient Balances In Microalgal Bioenergy System, Eunyoung Lee

USF Tampa Graduate Theses and Dissertations

This research investigated life cycle environmental impacts and benefits of an integrated microalgae system with wastewater treatment system using an integrated process modeling approach combined with experimentation. The overall goal of this research is to understand energy, carbon and nutrient balances in the integrated system and to evaluate the environmental impacts and benefits of the integrated system from a carbon, nutrient, and energy perspective. In this study, four major research tasks were designed to contribute to a comprehensive understanding of the environmental and economic sustainability of the integrated system, which included development of an integrated co-limitation kinetic model for microalgae …


Everglades Drainage District: Biennial Report 1927-1928 To The Board Of Commissioners Of Everglades Drainage District, F C. Elliot Jun 2017

Everglades Drainage District: Biennial Report 1927-1928 To The Board Of Commissioners Of Everglades Drainage District, F C. Elliot

City and Regional Planning -- Florida

Everglades Drainage District report 1927-1928


Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca Jun 2017

Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca

Civil Engineering ETDs

Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …