Water Technology and Efficiency
Occurrence of Emerging Contaminants in Lake Michigan and Sensory Development
The goals of this project are to determine the presence of selected emerging contaminants (pharmaceutical and hormones) in the waterbodies within the watershed of Lake Michigan in Northwest Indiana (NWI), to assess the emerging contaminant removal efficiencies of technologies employed by local WWTPs, to conduct preliminary studies on the removal of selected emerging contaminants using membrane filtration technologies, and to optimize the filtration process.
Mercury Reduction from Municipal Effluents Discharged into Lake Michigan
In this project, the mercury concentration and form in selected municipal effluents will be characterized; two technologies (UF membrane process and iron coprecipitation coupled with dynamic sand filtration) will be applied to remove mercury from municipal wastewater samples; and the unit efficiencies in removing mercury for two local wastewater treatment plants will be assessed.
East Chicago Water Filtration
Total Suspended Solids Profile and Strainer Study – PWI has completed batches of water sample collection at the East Chicago Filtration Plant to evaluate local strainers working condition and water treatment process line components’ TSS removal capacitiesTests and experiments of Total Suspended Solids, Turbidity and Particle Size & Distribution were conducted and the results have been analyzed. Also the membrane filters utilized during the TSS tests were imaged and analyzed by using scanning electron microscope (SEM), ingredients were identified and compared with each other under different situations.
Backwash Water Jar-test Study – The preliminary jar test study consisting of 202 tests was conducted to simulate the full-scale coagulation/flocculation treatment process at the East Chicago Water Treatment Plant. This study was designed to optimize the dosage of two types of poly aluminum chloride coagulants, AQ64 & AQ60 (Aquamark Inc.) for treatment of the retentate stream generated during water filtration, and to determine the optimal settling time based on turbidity reduction.
NWI Coastal Area Waste Water Treatment
PWI is in charge of the study for waste water characterization for presents of pharmaceutical and hormones contaminants and mercury to assess the local waste water treatment plants’ current removal efficiency of emerging contaminants as well as mercury in NWI coastal area. In the meanwhile, to determine individual contributions of emerging contaminants from different influent sources to the plants.
Emerging Technologies and Approaches to Minimize Discharges into Lake Michigan
The purpose of the PWI-Argonne study is to screen emerging technologies that could help BP and other Great Lakes area industries to address wastewater treatment challenges resulting from new and more stringent permit limits. The PWI-Argonne study will also generate a comparative analysis of municipal, industrial, and non-point source discharges to the Great Lakes Basin. BP will review the study results in evaluating whether there are new technologies and processes that could be implemented to treat the refinery’s process waste stream before it reaches the wastewater treatment facility, and/or at the facility itself.
Investigation of Hybrid Spring-membrane System for Fouling Control
This project presents numerical and experimental investigation of flux augmentation in hybrid spring ultrafiltration membrane system. The numerical simulation is based on the Eulerian multiphase model. Momentum exchange coefficient was used to account for interaction between the liquid–solid phases. The helical spring insert was modeled as filaments with defined pitch. The experimental facility consists of a two-pass spring-membrane system subjected to iso-transmembrane pressure and inlet velocity.
Fouling Mitigation for Hollow-fiber UF Membrane by Sonication
The project presents the experimental results of using ultrasonic waves to mitigate the fouling of the hollow-fiber ultrafiltration (UF) membrane process. While sonication has been reported to effectively enhance the performance of flat-sheet membrane filtration systems, little information is available regarding hollow-fiber membrane even though hollow-fiber has been a popular membrane configuration for industrial applications. In this work, both online continuous and offline pulse ultrasonic irradiation processes have been employed and their effectiveness on the fouling mitigation were evaluated and reported. The effects of ultrasonic frequencies and power intensities on the permeate flux were evaluated employing a synthetic clay solution. Experimental results indicated that sonication at higher intensity and lower frequency substantially reduced membrane fouling and in turn enhanced the permeate flux of the filtration process.
Lake Michigan Water Resources Study
This study contains an analysis of withdrawal data for North West Indiana to compute consumptive-use coefficients and to describe monthly variability of withdrawals and consump¬tive use. Water quality analysis is presented and historic water quality data of Northwest Indiana, (Lake, Porter and LaPort Counties) were examined for the trends in different water quality constituents. Individual station based analysis and regional analysis were conducted using MK Test. Water quality data indicated an improvement trend. Water withdrawals data were analyzed using regression and Artificial Neural Network (ANN) models. Consumptive use and consumptive-use coefficients were computed by two principal methods in this study: the return-flow and withdrawal method and the winter-base-rate method (WBR).
Lake County Soil & Water Conservation District Private Well Testing Program
In order to better serve the local communities, PWI performs the private well water testing including turbidity, total suspended solids, dissolved oxygen, oxidation reduction potential, ions (nitrate, nitrite, chloride, soluble phosphorus, and fluoride), specific conductivity, total dissolved solids, pesticides, VOCs and twenty-three heavy metals detections for sixty-four residents located in Lake, LaPorte and Porter County. Water quality related information such as EPA primary and secondary drinking water regulations, water issues trouble shooting suggestions is included in the testing reports for educational proposes.
Predicting Northwest Indiana’s Water Quality (Ruijian Zhang)
Water quality prediction is becoming a major challenge in Northwest Indiana and Lake Michigan region. Two attractive alternatives of water quality modeling and prediction may be to express the complex behavior of the nature in Northwest Indiana and Lake Michigan region. One of them applies Bayesian network to predict the water quality probabilistically, as in statistical mechanics. The other employs C5 as decision tree modeling tool to make the water quality prediction. This study will investigate the potential for probability network and decision tree models to support water quality assessment and prediction in Northwest Indiana and compare these two methods with conventional mechanistic models.
Sensor Technology (Don Gray, George Nnanna, and Hal Pinnick)
Distribution Systems have been recognized as the part of water supply systems that is most vulnerable to deliberate contamination. In order to be truly innovative, new monitoring systems need to be able to operate unattended, online, in real time and be integrated into a distributed sensor network that minimizes false positives and negatives.
The PWI has embarked on two major sensor projects: a) Multi-parameter sensors where a suit of sensors (PH, turbidity, conductivity, dissolved oxygen) will be instrumented in a water distribution piping network to detect changes in physiochemical and thermal properties of water in the presence of contaminants. In this effort, a lab-scale model of the City of Hammond, IN, water piping network will be designed and built, and sensors attached to pre-selected locations will monitor the variations in contaminant concentration and properties. b) Quartz Crystal Microbalance (QCM) is a miniature scale which weighs the presence of target ions or molecules. The crystal is excited electronically and made to oscillate. The targets, the ions or molecules, are attracted to the QCM that are deposited on the surface of the crystal. The weight or mass of the target on the receptor chemistry slows down the oscillations on the crystal indicating the presence of the target. Presently, PWI is collaborating with Quansor Corporation located at the Purdue Research Park in this effort.
Discrete Optofluidic chemical Spectrophotometry System (DOCSS)
PWI designed a discrete chemical auto-analyzer system for in-situ monitoring of dissolved chemical pollutants such as heavy metals (mercury, Chromium (VI), and arsenic), nitrites, chlorides etc. in both static and dynamic water system. The device can be remotely controlled over the internet, thus making it very suitable for monitoring of chemical pollutants in remote locations. The performance was evaluated using the spectrophotometric analysis of chromium (VI) with di-phenylcarbazide as model chemistry. The results showed very good stability in the optical absorbance measurement, a method detection limit of 6.38ppb, and good precision of 3.0% RSD at 50ppb Cr (VIk). Also a linear calibration range of 25ppb to 1250ppb was obtained, and the response was reversible.
Mathematical Model of Contaminant Transport (George Nnanna)
One of the fundamental problems in online water monitoring system is determination of the optimum location of the sensor in order to effectively detect the contaminant at high concentration. This study is to develop a MATLAB code which will predict the concentration of any contaminant which might be introduced into the drinking water system. MATLAB is a powerful software package with many built in functions useful in almost all engineering applications. Mass balance equations are solved to get a governing equation which contains concentration ‘C’ as a function of distances in ‘x’, ‘y’ and ‘z’ directions and time ‘t’.
Reversible Evanescent-based Opto-chemical Sensor for In-situ Detection of Contaminants in Static and Dynamic Fluid System
The main objectives of this project are to fabricate a reversible Clad-modified Opto-chemical Plastic Fiber Sensor (OCPFS) for the instantaneous detection of ammonia in both static and dynamic aqueous media and to evaluate its dynamic range, sensitivity, time response, and life cycle. In this work, Plastic Optical Fiber (POF) was modified and applied as an optical waveguide. The sensor developed in this study showed excellent repeatability, response time (within 10 seconds of the ammonia concentration change), and reversibility (99% recovery within 50 seconds upon ammonia removal). Results showed that the sensor was very sensitive to ammonia at low ammonia concentration range. These outstanding and productive behaviors of this sensor established its practical implementation in the real life.
Validation of Inductively Coupled Plasma Spectroscopy (ICP), (Anita Katti)
The Inductively Coupled Plasma Spectroscopy (ICP) measures and quantifies metals in a solution in one step with a single introduction of sample. Its design uses a sensor array to detect the signals of “all” metals simultaneously. The ICP has been installed with access to a 220 V line and an elephant trunk hood. Presently, a PWI faculty is testing and validating the equipment. The ICP will be tested using calibration standards and calibration standard mixture solutions readily available from vendors and suppliers in order to master the software as well as evaluate the accuracy and precision of the instrument for selected elements. The ICP will be validated by measuring the limit of detection and the limit of quantification for the same selected metals.
Waste water Reuse Assessment in Northwest Indiana, William Rutherford and George Nnanna
The goal of this project is to assess, through statistical analyses, the amount of wastewater generated in the Northwest Indiana region that is being treated and reused for other requirements on a county by county basis. This data will then be used to determine methods to improve the quality of the water. Included in this study are the amount of water that is currently being consumed by agriculture, industry, and residential/commercial groups and their corresponding sources.
Fabrication and Calibration of Silicon-based Ball-tip Optical Ammonia Sensor for On-line In-situ Detection in Water System
This project describes the design, development and characterization of a silicon-based ball-tip optical fiber sensor for monitoring ammonia concentration in solutions. It is an extrinsic optic fiber sensor which is based on the light transmission absorption mode. An effective method has been developed to mix the pH indicator with PDMS as the sensing material by using ultrasound stirring, and a tip coating approach has been successfully applied to attach the sensing material on the optical fiber tip. The size of the sensing element is less than 4mm2. However, the sensitivities of the sensor using the bromocresol purple are as low as 100ppb and 300ppb in the stagnant and dynamic solutions respectively. It also exhibits short response time, a good reversibility and long working life time. It detects ammonia within 10 seconds and shows more than 96% reversibility even though it is used for more than 20 days. An efficient calibration method has been invented to remove the interruptive factors such as temperature, pressure and light source input intensity alterations.
Raltson Street Lagoon Project, 2006, ($17,300.00), Gary Sanitary District (GSD), Gary, IN, Awarded, George Nnanna, Hal Pinnick, Anita Kitta
The objective of this project is to examine the reports submitted by CDM to GSD on the current status of the PolyChlorinated Biphenyls (PCB) content of the Ralston Street Lagoon. Based on assessment of the reports, the PurdueNorthwest Water Institute (PWI) will recommend an economically feasible remediation plan for the lagoon.