Clean Water - Help Environment - Pure Water - Water Purifier
Filtration - Bottle Water - Fresh Water - Poison Free
The objective of this research was to investigate the clogging process in riverbank filtration (RBF) systems and identify factors significant to yield. Specific objectives included the following:
- Evaluate commonly available stream and aquifer characteristics from RBF systems with regards to system yield
- Collect data from the RBF system in Louisville and apply the information to clogging theory
- Provide recommendations regarding the design of future RBF systems with regards to riverbed clogging
- Data from the participating sites were compiled to allow easy comparison to future RBF sites.
High-capacity RBF systems have been constructed in a wide range of hydrogeologic settings, and data from these sites provide insight to capacity-limiting factors in RBF systems. Field data for temperature, head, and riverbed flux rates into the riverbed were collected at Louisville, allowing estimates of riverbed hydraulic conductivity to be calculated as a function of distance from the well. These data indicated variations in riverbed hydraulic conductivity resulting from riverbed clogging and the development of unsaturated conditions. The impact of temperature on specific capacity was evaluated at four sites where adequate operating data were available. Wide variations in water viscosity associated with temperature resulted in the doubling of specific capacity from winter to summer, indicating that the rated capacity of RBF systems should be considered as a range between coldest and warmest water conditions. Information from this project was summarized into a set of recommendations for utilities considering the design of an RBF system for future water supply.
As the quantity and quality of inland water sources decline, more coastal municipalities are looking at seawater desalination as a potential source of drinking water. The Long Beach Water Department (LBWD) developed an alternative technology to desalt seawater by using dual-staged nanofiltration (NF2). This novel NF system treats the first-stage permeate through a second stage in order to produce finished water with salinity levels that meet drinking water standards.
Three commercially-available NF membranes were selected for this study based upon their designation as NF membranes by the manufacturers and their salt rejection characteristics. Results from the bench-scale evaluation were integrated in a performance-predicting model, which was subsequently calibrated against the results obtained with an 8-gpm pilot unit. The pilot-test plan considered the impact of temperature, pressure, and array configuration on permeate water quantity and quality. The percentage of desalinated water that could be blended into LBWD's distribution system was determined by taking into account the issues of disinfection by-product (DBP) formation, disinfectant residual, and corrosivity. Finally, viral challenge tests were considered to verify the inherent redundancy of the system and the impact that recycling streams would have on virus accumulation.
Sustainable Water Solutions Articles
Sustainable Water Solutions Books