Chip Kilduff | Rensselaer Polytechnic Institute (original) (raw)

Papers by Chip Kilduff

Renewable Energy Technologies and Water Infrastructure, 2022

Water Science and Technology, 2001

Five natural waters with a broad range of DOC concentrations were fractionated using various coal... more Five natural waters with a broad range of DOC concentrations were fractionated using various coal- and wood-based granular activated carbons (GAC) and alum coagulation. Adsorption and alum coagulation fractionated NOM solutions by preferentially removing components having high specific ultraviolet absorbance (SUVA). UV absorbing fractions of NOM were found to be the major contributors to DBP formation. SUVA appears to be an accurate predictor of reactivity with chlorine in terms of DBP yield; however, it was also found that low-SUVA components of NOM have higher bromine incorporation. SUVA has promise as a parameter for on-line monitoring and control of DBP formation in practical applications; however, the effects of bromide concentration may also need to be considered. Understanding how reactivity is correlated to SUVA may allow utilities to optimize the degree of treatment required to comply with DBP regulations. The reactive components that require removal, and the degree of trea...

ACS Symposium Series, 2008

During chlorination of natural water, chlorine reacts with naturally present dissolved organic ma... more During chlorination of natural water, chlorine reacts with naturally present dissolved organic matter (DOM) to form potentially hazardous chlorinated hydrocarbons, so-called disinfection byproducts (DBPs)(1). In the presence of bromide ion, brominated DBPs are formed in parallel with chlorinated species. Research has suggested that DBP toxicity increases with increasing bromine substitution (2). Controlling DBP formation is increasingly important as the allowable concentrations of such DBPs as trihalomethanes (THMs) and haloacetic ...

2008 38th Annual Frontiers in Education Conference, 2008

ABSTRACT

Journal of Membrane Science, 2011

Journal of Environmental Engineering, 1989

On‐site sewage disposal systems (commonly septic tank/soil absorption systems) provide a viable a... more On‐site sewage disposal systems (commonly septic tank/soil absorption systems) provide a viable and permanent management alternative for the treatment and disposal of wastewater in rural, unsewered communities. Population expansion in rural and semirural areas has presented challenges to develop economical, efficient on‐site sewage disposal systems in severly limited areas. Building sewage disposal systems in fill can be used to overcome site limitations such as high groundwater and shallow depth to ledge. An efficient design balances the requirements of hydraulic and renovation capacity, which depend strongly on the compacted, in‐situ permeability of the emplaced fill specified in the design phase. This paper reviews the procedures used to design subsurface sewage disposal systems in emplaced fill, to illustrate the importance of fill permeability and its relationship to system performance and economy. Procedures are suggested for identifying and verifying suitable material and for placing fill to meet d...

Environmental Science & Technology, 1996

The adsorption of several different organic polyelectrolytes from aqueous solution by activated c... more The adsorption of several different organic polyelectrolytes from aqueous solution by activated carbon was characterized. Polyelectrolytes included humic acids extracted from peat and soil, polymaleic acid, a synthetic polymer identified as a fulvic acid surrogate, and natural organic matter in Huron River (Ann Arbor, MI) water. Isotherms of individual ultrafiltration size fractions confirmed that smaller molecular size components adsorb to a greater extent on an adsorbent mass basis. The molecular weight distributions of organic ...

Environmental Engineering Science, 2002

Poly(ether sulfone) and sulfonated poly(sulfone) nanofiltration membranes were modified by UV irr... more Poly(ether sulfone) and sulfonated poly(sulfone) nanofiltration membranes were modified by UV irradiation and UV-assisted graft polymerization of N-vinyl-2-pyrrolidinone (NVP) as a strategy for increasing the wettability of membrane surfaces and mitigating fouling by naturally occurring organic compounds present in surface waters. The UV-assisted graft polymerization approach with 3% NVP and a reaction time of 60 s increased the wettability (increased cos u) of membrane surfaces, which exhibited a significantly lower propensity to foul. For these conditions, clean water permeability and solute rejection (as organic carbon) were maintained close to that of the as-received membranes. Graft polymerization was carried out using two different methods. With the dip method, membrane coupons coated with a 3% N-vinyl-2-pyrrolidinone solution were UV irradiated under nitrogen. With the immersion method, membrane coupons were irradiated directly in nitrogen-purged 3% NVP solution. Both techniques increased membrane wettability; however, the immersion technique required much longer reaction times resulting from the absorption of UV radiation by the monomer solution. Flux decline of modified membranes was well described using a combined pore blockage/cake filtration model that was modified to incorporate back-transport. Model results provide support for the interpretation that the enlargement of the membrane pore structure caused by long irradiation times allowed additional pore fouling by larger molecular weight natural organic matter components that were previously rejected.

Desalination, 2000

Journal of Chemical Education, 1995

Microbial Electrochemical Technology, 2019

Abstract State-of-the-art bioelectrochemical systems for water and wastewater treatment that empl... more Abstract State-of-the-art bioelectrochemical systems for water and wastewater treatment that employ membrane separators are exposed to foulants that degrade membrane and process performance. Here we review potential foulants, including inorganics, humic substances, colloids, microbes, and microbially generated foulants such as extracellular polymer substances, microbial debris, and proteins. We introduce major fouling mechanisms, including pore blockage, pore constriction, cake formation, and biofouling. We discuss antifouling strategies, critical to maintain performance of membrane-based systems, including module design with an emphasis on the importance of surface shear, and membrane selection with an emphasis on promoting interactions with water. Membrane surface modification is discussed as a way to optimize surface chemistry, via physical adsorption, bulk modification, polymer blending, interfacial polymerization, and graft polymerization, including photoinitiated and atom transfer radical polymerization. Finally, we present a case study on the use of UV-irradiated graft polymerization for obtaining energy-efficient membranes in an integrated microbial fuel cell/ultrafiltration process used for recycling municipal wastewater.

2006 Annual Conference & Exposition Proceedings

Environmental biotechnology, the application of living organisms to environmental problems, is an... more Environmental biotechnology, the application of living organisms to environmental problems, is an increasingly important topic. One notable example is bioremediation, i.e., the use of microorganisms to clean up contaminated environments, including contaminated soils and sediments. Environmental biotechnology is at the interface of biology and engineering, which presents both significant opportunities and limitations. Effective application of environmental biotechnology requires professionals who have a background in both areas. The undergraduate engineering curriculum has traditionally not emphasized training in biological sciences, although many environmental engineering curricula have incorporated some engineering microbiology in concert with, or as a prerequisite for, wastewater treatment courses. In general, however, whereas environmental engineers have considerable engineering skills required for the design of processes per se, have only a rudimentary knowledge of general biology and microbiology in particular. Growth in biology-related courses in the engineering curriculum is becoming more widespread, as chemical engineering departments begin to emphasize life science related research, and as biomedical engineering departments grow and diversify. Thus, the development of an Environmental Biotechnology course satisfies an urgent need in terms of professional preparation, and is timely as biology becomes more integrated into the engineering curriculum. The proposed environmental biotechnology course will develop in environmental engineers an awareness of the most relevant, often diverse, aspects of the subject. The course will begin with general microbiology including structure, metabolism, growth kinetics, genetics, ecology, and diversity of microorganisms. This will prepare students for more in-depth treatment of such topics in other courses, and for important and emerging engineering applications of environmental biotechnology dicussed in the second half of the proposed course. These include state-of-the-art advances in wastewater treatment (including removal of carbon, nitrogen, and phosphorus; transformation of anthropogenic chemicals; and water re-use); bioremediation, including bioaugmentation and natural attenuation; production and mechanism of biofertilizers and biopesticides; fundamental and practical aspects of biosensor mechanism, design and implementation; development of microbial fuel cells; generation of valuable products from wastes; applications and ecology of biolfilms; quorum sensing (microbial cell-cell communication), and environmental genomic

2002 Annual Conference Proceedings

The model reservoir, and the equipment required to carry out the classroom demonstration, are sho... more The model reservoir, and the equipment required to carry out the classroom demonstration, are shown in Fig. 1. All the required equipment can be transported using a laboratory cart. The model reservoir itself (also shown in detail in Figure 2) is a one-liter glass solvent bottle fitted with a discharge orifice made from a short piece of glass tubing (6-mm outside diameter, 4-mm inside diameter). The discharge is located near the bottom of the bottle. A peristaltic pump with a flow controller was used to provide inflow to the reservoir, and outflow was collected in a plastic tub. While in principle any inflow hydrograph shape could be delivered, step changes in flowrate, resulting in "square wave" hydrographs, are most readily accomplished. Water for the experiment (feed solution) was stored in one-gallon bottles. Water volumes were measured using either a 100-mL or 250-mL graduated cylinder, and flow rates were calculated from the time required to fill a known volume, using a stopwatch and a graduated cylinder. Water surface elevations were measured using a ruler or engineers scale.

Water Science and Technology, 2004

We propose an educational experience in which students design a membrane gas transfer reactor, co... more We propose an educational experience in which students design a membrane gas transfer reactor, construct a bench-scale version in the laboratory, and employ the reactor to measure mass transfer coefficients. The membrane reactor is useful for teaching mass transfer principles because the mass transfer interface is well defined and easily observed. The system can be modeled successfully using straightforward mathematics. The reactor can be designed and constructed by students, using the mathematical model as a basis, providing insight into the physical meaning of model parameters. The proposed membrane system can be readily operated to obtain data that can be employed to develop or modify existing mass transfer correlations. This can provide students with significant insight into the development of mass transfer correlations and how the constants in such correlations are typically determined. These features help promote a deeper understanding of mass transfer principles.