Grantee Research Project Results
Final Report: Development and Demonstration of a Bench-Scale Prototype for the Effective Removal of Selenium in Wastewater
EPA Contract Number: 68D98150Title: Development and Demonstration of a Bench-Scale Prototype for the Effective Removal of Selenium in Wastewater
Investigators: Downing, Michael W.
Small Business: HYDRO-Solutions and Purification LLC.
EPA Contact: Richards, April
Phase: I
Project Period: September 1, 1998 through March 1, 1999
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (1998) RFA Text | Recipients Lists
Research Category: Watersheds , SBIR - Water and Wastewater , Small Business Innovation Research (SBIR)
Summary/Accomplishments (Outputs/Outcomes):
On August 21, 1998, HYDRO-Solutions and Purification, LLC. (HS&P), 530 7th Ave, Suite 2B, Fairbanks Alaska, 99701, entered into a Phase I grant contract with EPA for the Development and Demonstration of a Bench Scale Prototype for the Effective Removal of Selenium in Wastewater Utilizing Enhanced Iron Co-precipitation. Approximately half of the contract period of 6 months was dedicated to laboratory testing, site selection and prototype development, while the other half consisted of field testing and continuing laboratory study.Laboratory testing was performed at facilities provided by the Mineral Industry Research Center (MIRL), on the campus of the University of Alaska-Fairbanks (UAF), with analytical services provided by Dr. Rudy Candler of the UAF Agriculture and Forestry Research Station (AFES) in Palmer, Alaska.
The field testing was performed in the Panoche Water and Drainage District (PWDD), at drainage point 25 (DP-25), approximately 70 miles northwest of Fresno, in the California's Central Valley. This valley stretches from Merced to Fresno, to Tulare, south of Sacremento to the San Juaquin drainage basin. It contains approximately 500,000 acres of the most productive agricultural land in the world, producing: tomatoes, garlic, cotton, cantaloupes and grapes. It is, at the same time, some of the most heavily irrigated farmland and the consequent leaching of selenium from the soil, due to irrigation, is the source of the selenium rich drainage water which has resulted in severe environmental problems for California. The PWDD represents approximately 44,000 acres of the Central Valley and produces cantaloupe, tomatoes, garlic, cotton, rice, onions and wine grapes.
Analytical services during field testing were provided by BSK Analytical Laboratories in Fresno, with confirmation analysis, on duplicate samples, provided by UAF AFES.
In the laboratory study selenium levels were effectively reduced from 0.500 ppm to <0.010 ppm a (98% reduction). Results from the field testing, while not as effective, did achieve a 90% reduction of selenium. The action of enhanced iron co-precipitation process was inhibited by the presence of high sulfates in the water at the selected demonstration site, resulting in a need to remove the sulfates with pre-processing. The addition of barium, as barium chloride, proved effective in removing sulfates and reducing selenium levels using a combination of barium pre-treatment and enhanced iron co-precipitation. HYDRO-Solutions and Purification is continuing with its laboratory study in order to improve the effectiveness of future field trials.
HS&P concluded, from data collected during this project, that a combination of barium pre-treatment and Enhanced Iron Co-precipitation was highly effective under laboratory conditions (98% selenium removal). In the field, the process needs to be studied further, in order to improve the selenium removal efficiency (90%) achieved during the Phase I contract.
Personnel with the Panoche Water and Drainage District were frequent visitors to the testing site, while a representative, of the California Department of Environ-mental Conservation (CEPA) drove down from San Francisco to inspect the site and discuss the on-going results of the project. Personnel from the PWDD, it's board of directors and CEPA are very supportive for HYDRO-Solutions and Purification's continuing efforts toward obtaining EPA Phase II funding for commercialization of the selenium removal process developed in Phase I. PWDD, and its board, has expressed interest in the commercialization aspect of the HS&P process as an end-user. Successful results with the commercialization effort will open the whole 500,000 acres of the Central Valley for drainage water treatment of selenium and sulfate contamination, in addition to other agricultural areas of the U.S. and abroad with similar environmental problems.
Supplemental Keywords:
Economic, Social, & Behavioral Science Research Program, Scientific Discipline, Toxics, Water, Waste, Sustainable Industry/Business, National Recommended Water Quality, Environmental Chemistry, cleaner production/pollution prevention, Wastewater, Remediation, Chemistry, Engineering, Environmental Engineering, Engineering, Chemistry, & Physics, Hazardous, Economics & Decision Making, wastewater treatment, contaminated waste sites, economic benefits, Iron Co-Precipitation Process, cost/benefit analysis, Selenium, bench scale, chemical precipitation processes, water quality, contaminant removal, bench scale characterisitcs, cost effectivenessThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.