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- Title
- Technical Feasibility of Nanofiltration Concentrate Treatment with Low Pressure Reverse Osmosis.
- Creator
- Toro, Adriana M., Bloetscher, Frederick, Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
This study evaluated the technical feasibility o f increasing the typical water recovery of a pilot scale membrane system (85-90%) to 97% by treatment of nanofiltration concentrate with low-pressure reverse osmosis. The study used Biscayne aquifer water (freshwater), and determined that it may be technically feasible to increase the recovery up to approximately 95% when the RO flux is —10 gfd, the feed water pH is reduced to -6.1 with H2 SO4 , and antiscalant in the NF process. The tested...
Show moreThis study evaluated the technical feasibility o f increasing the typical water recovery of a pilot scale membrane system (85-90%) to 97% by treatment of nanofiltration concentrate with low-pressure reverse osmosis. The study used Biscayne aquifer water (freshwater), and determined that it may be technically feasible to increase the recovery up to approximately 95% when the RO flux is —10 gfd, the feed water pH is reduced to -6.1 with H2 SO4 , and antiscalant in the NF process. The tested membranes showed stable and similar performance under the pilot conditions. However, pilot tests were sensitive to pH variations (pH>6.2). The main barrier for increasing the water recovery was fouling caused by iron, carbonate hardness, and iron bacteria. A preliminary cost analysis showed that there is an apparent econom ic advantage when the recovery is greater than 90%. Estimated water cost at 95% recovery is $1.99 compared with $2.69 at the typical 85% recovery.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00012564
- Subject Headings
- Saline water conversion--Reverse osmosis process, Water--Purification--Reverse osmosis process, Membrane separation, Membranes (Technology)
- Format
- Document (PDF)
- Title
- Salinity Assessment, Change, and Impact on Plant Stress / Canopy Water Content (CWC) in Florida Bay using Remote Sensing and GIS.
- Creator
- Selch, Donna, Zhang, Caiyun, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Human activities in the past century have caused a variety of environmental problems in South Florida. In 2000, Congress authorized the Comprehensive Everglades Restoration Plan (CERP), a $10.5-billion mission to restore the South Florida ecosystem. Environmental projects in CERP require salinity monitoring in Florida Bay to provide measures of the effects of restoration on the Everglades ecosystem. However current salinity monitoring cannot cover large areas and is costly, time-consuming,...
Show moreHuman activities in the past century have caused a variety of environmental problems in South Florida. In 2000, Congress authorized the Comprehensive Everglades Restoration Plan (CERP), a $10.5-billion mission to restore the South Florida ecosystem. Environmental projects in CERP require salinity monitoring in Florida Bay to provide measures of the effects of restoration on the Everglades ecosystem. However current salinity monitoring cannot cover large areas and is costly, time-consuming, and laborintensive. The purpose of this dissertation is to model salinity, detect salinity changes, and evaluate the impact of salinity in Florida Bay using remote sensing and geospatial information sciences (GIS) techniques. The specific objectives are to: 1) examine the capability of Landsat multispectral imagery for salinity modeling and monitoring; 2) detect salinity changes by building a series of salinity maps using archived Landsat images; and 3) assess the capability of spectroscopy techniques in characterizing plant stress / canopy water content (CWC) with varying salinity, sea level rise (SLR), and nutrient levels. Geographic weighted regression (GWR) models created using the first three imagery components with atmospheric and sun glint corrections proved to be more correlated (R^2 = 0.458) to salinity data versus ordinary least squares (OLS) regression models (R^2 = 0.158) and therefore GWR was the ideal regression model for continued Florida Bay salinity assessment. J. roemerianus was also examined to assess the coastal Everglades where salinity modeling is important to the water-land interface. Multivariate greenhouse studies determined the impact of nutrients to be inconsequential but increases in salinity and sea level rise both negatively affected J. roemerianus. Field spectroscopic data was then used to ascertain correlations between CWC and reflectance spectra using spectral indices and derivative analysis. It was determined that established spectral indices (max R^2 = 0.195) and continuum removal (max R^2= 0.331) were not significantly correlated to CWC but derivative analysis showed a higher correlation (R^2 = 0.515 using the first derivative at 948.5 nm). These models can be input into future imagery to predict the salinity of the South Florida water ecosystem.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004686, http://purl.flvc.org/fau/fd/FA00004686
- Subject Headings
- Environmental management, Florida Bay (Fla.), Geographic information systems, Geospatial data, Marine ecology, Plant water relationships, Remote sensing, Salinity -- Florida -- Florida Bay -- Measurement
- Format
- Document (PDF)
