Impact/Purpose:
The objective of this research project is to
understand how the presence of silica (sand) particles impacts drinking water
treatment processes.
This project will seek answers to the following questions:
1. How do silica particles affect the coagulation, flocculation, and sedimentation
processes? How do the observed effects compare with the effects when monosilicic
acid or polysilicates are present?
2. Mechanistically, how do silica particles interact with coagulants during
water treatment?
3. In what types of source waters is the addition of silica beneficial?
Description:
EPA Identifier: U915331
Title: Interactions of Silica Particles in Drinking Water Treatment Processes
Fellow (Principal Investigator): Christina L. Clarkson
Institution: Virginia Polytechnic Institute and State University
EPA GRANT Representative: Delores Thompson
Project Period: August 1, 1998 - August 1, 2000
Project Amount: $55,314
RFA: STAR Graduate Fellowships
Research Categories: Academic Fellowships, Engineering and Environmental Chemistry, Fellowship - Environmental Engineering
Description
Objective:The objective of this research project is to
understand how the presence of silica (sand) particles impacts drinking water
treatment processes.
This project will seek answers to the following questions:
1. How do silica particles affect the coagulation, flocculation, and sedimentation
processes? How do the observed effects compare with the effects when monosilicic
acid or polysilicates are present?
2. Mechanistically, how do silica particles interact with coagulants during
water treatment?
3. In what types of source waters is the addition of silica beneficial?
Approach:
Silica interactions will be investigated by tracking
particle behavior in the presence and absence of sand. Particles (combinations
of natural turbidity,
silica, and coagulant) will be characterized by filtration through a 0.45 micrometer
pore size filter, a zeta potentiometer, and a submicron particle sizer. The
goal is to understand the effects of silica on relative rates of chemical nucleation,
precipitation, particle agglomeration, and sedimentation. As part of that evaluation,
water quality effects, rate of chemical addition, and order of chemical addition
will be investigated. It is anticipated that the results will provide improved
fundamental understanding, which can be applied to further optimizing the relatively
new sand-ballasted process.
Supplemental Keywords: fellowship, sorption, silica, coagulation, flocculation, sedimentation, monosilicic acid, polysilicates, drinking water treatment, source water, zeta potentiometer, submicron particle sizer, chemical nucleation, precipitation, particle agglomeration, silica, silica particles., Scientific Discipline, RFA, Wastewater, Engineering, Chemistry, & Physics, Civil/Environmental Engineering, other - risk management, TOC removal, drinking water regulations, particle removal, microsand enhanced coagulation, alternative technology
Keywords:
FELLOWSHIP, SORPTION, SILICA, COAGULATION, FLOCCULATION, SEDIMENTATION, MONOSILICIC ACID, POLYSILICATES, DRINKING WATER TREATMENT, SOURCE WATER, ZETA POTENTIOMETER, SUBMICRON PARTICLE SIZER, CHEMICAL NUCLEATION, PRECIPITATION, PARTICLE AGGLOMERATION, SILICA, SILICA PARTICLES.,
Related Organizations:
Role
:OWNER
Organization Name
:VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY
Citation
:Blacksburg
State
:VA
Zip Code
:24061
Project Information:
Approach
:Silica interactions will be investigated by tracking
particle behavior in the presence and absence of sand. Particles (combinations
of natural turbidity,
silica, and coagulant) will be characterized by filtration through a 0.45 micrometer
pore size filter, a zeta potentiometer, and a submicron particle sizer. The
goal is to understand the effects of silica on relative rates of chemical nucleation,
precipitation, particle agglomeration, and sedimentation. As part of that evaluation,
water quality effects, rate of chemical addition, and order of chemical addition
will be investigated. It is anticipated that the results will provide improved
fundamental understanding, which can be applied to further optimizing the relatively
new sand-ballasted process.
Cost
:$55,314.00
Research Component
:Fellowship - Environmental Engineering
Risk Paradigm
:RISK MANAGEMENT
Approach
:
Silica interactions will be investigated by tracking
particle behavior in the presence and absence of sand. Particles (combinations
of natural turbidity,
silica, and coagulant) will be characterized by filtration through a 0.45 micrometer
pore size filter, a zeta potentiometer, and a submicron particle sizer. The
goal is to understand the effects of silica on relative rates of chemical nucleation,
precipitation, particle agglomeration, and sedimentation. As part of that evaluation,
water quality effects, rate of chemical addition, and order of chemical addition
will be investigated. It is anticipated that the results will provide improved
fundamental understanding, which can be applied to further optimizing the relatively
new sand-ballasted process.
Cost
:$55,314.00
Research Component
:OTHER
Risk Paradigm
:RISK MANAGEMENT
Approach
:
Silica interactions will be investigated by tracking
particle behavior in the presence and absence of sand. Particles (combinations
of natural turbidity,
silica, and coagulant) will be characterized by filtration through a 0.45 micrometer
pore size filter, a zeta potentiometer, and a submicron particle sizer. The
goal is to understand the effects of silica on relative rates of chemical nucleation,
precipitation, particle agglomeration, and sedimentation. As part of that evaluation,
water quality effects, rate of chemical addition, and order of chemical addition
will be investigated. It is anticipated that the results will provide improved
fundamental understanding, which can be applied to further optimizing the relatively
new sand-ballasted process.
Cost
:$55,314.00
Research Component
:Engineering and Environmental Chemistry
Risk Paradigm
:RISK MANAGEMENT
Approach
:
Silica interactions will be investigated by tracking
particle behavior in the presence and absence of sand. Particles (combinations
of natural turbidity,
silica, and coagulant) will be characterized by filtration through a 0.45 micrometer
pore size filter, a zeta potentiometer, and a submicron particle sizer. The
goal is to understand the effects of silica on relative rates of chemical nucleation,
precipitation, particle agglomeration, and sedimentation. As part of that evaluation,
water quality effects, rate of chemical addition, and order of chemical addition
will be investigated. It is anticipated that the results will provide improved
fundamental understanding, which can be applied to further optimizing the relatively
new sand-ballasted process.
Cost
:$55,314.00
Research Component
:Academic Fellowships
Risk Paradigm
:RISK MANAGEMENT
Project IDs:
ID Code
:U915331
Project type
:Fellowship