The Effectiveness of Polyacrylamide in Reducing Turbidity Caused by High Clay Sediment - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook The Effectiveness of Polyacrylamide in Reducing Turbidity Caused by High Clay Sediment write by . This book was released on 2007. The Effectiveness of Polyacrylamide in Reducing Turbidity Caused by High Clay Sediment available in PDF, EPUB and Kindle. Polyacrylamide was studied for its efficacy in reducing turbidity. The purpose of this research was to determine optimum conditions for 10 blends of PAM to reduce turbidity from construction site runoff. The research was based on 10 different PAM blends, researching concentrations (0, 1, 5, 10 ppm), PAM forms (dry granular or solution), mixing powers (80 and 150 rpm), and mixing times (1 and 2 minutes). The research was conducted in a laboratory setting using a PB-700 [trade mark] Standard Jar Tester (Phipps and Bird, Richmond, Virginia) with a clay texture sediment source. The clay-textured sediment source was researched under two sediment-water concentrations of 2,000 and 10,000 parts per million (ppm). For non-polymer control, each sediment concentration was mixed for five minutes to ensure complete mixing. One minute after the cessation of mixing, turbidity measurements were taken on time intervals of 0.5, 2, 5, and 10 minutes. Using these same samples, polyacrylamide was then added to the sediment-water solution. Three replicates of the various treatment conditions, and similar turbidity measurements were then taken. The data showed the most key aspects, on the average at reducing turbidity the greatest, were the dry forms of PAM for the 2,000 ppm sediment-water concentration and the solution forms of PAM for the 10,000 ppm sediment-water concentrations. Turbidity reductions were not as dramatic with the dry form of PAM, at the lower mixing power, with the shorter mixing time, at low PAM concentrations. The data also provided evidence that all PAM blends demonstrate different turbidity reduction under different treatment combinations. This information shows the important issue that PAM is not exactly 100% PAM and each PAM product (blend) are very soil dependent. This key issue needs to be considered when a PAM product is applied in any form or fashion.
Polyacrylamide For Turbidity Control in Runoff: Effects of Polyacrylamide, Soil, and Solution Properties
Polyacrylamide For Turbidity Control in Runoff: Effects of Polyacrylamide, Soil, and Solution Properties - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Polyacrylamide For Turbidity Control in Runoff: Effects of Polyacrylamide, Soil, and Solution Properties write by . This book was released on 2003. Polyacrylamide For Turbidity Control in Runoff: Effects of Polyacrylamide, Soil, and Solution Properties available in PDF, EPUB and Kindle. Eroded soil discharged from construction sites is a major water quality issue. North Carolina regulations require that the turbidity of discharged waters from construction sites to non-trout streams or reservoirs not exceed 50 nephelometer turbidity units (NTU) and 10 NTU in trout waters. Polyacrylamide (PAM) has been demonstrated to reduce erosion and turbidity in runoff, but there is little information on the interactions between PAM properties and that of the water or suspended solids. Our study tested eight PAM products (Cytec Superfloc A100, A110, A150, N300, 1606; Ciba Soilfix Polybead; Applied Polymer Systems 705; Chemtall 923VHM) at concentrations from 0 to 10 mg L-1 for turbidity reduction in suspensions of 13 soils from active construction sites around North Carolina. For five soil suspensions, with turbidities of up to 3000 NTU, PAM reduced turbidity to below 50 NTU in 30 s. In addition turbidity reductions to the 10 NTU level were observed for two soils. Overall, turbidity reductions of greater than 86% were achieved for all soils. Optimal PAM concentrations of soils tested were 1-2 mg L-1, with higher concentrations causing turbidity increases in some soils. Sediment properties drastically affected the response to PAM, which indicates the need to have site-specific recommendations for PAM use. Sediments with turbidity reductions below the 50 NTU standard had kaolinite as the dominant clay mineral (70-90%), a pH between 5-6, and very low organic matter. Soils from the Coastal Plain had poor turbidity reduction with most PAMs. APS705, which contains a mixture of polymers with different molecular weights and charge density, was the only polymer that effectively reduced turbidity in all Coastal Plain soils. An evaluation using combinations of low and high molecular weight PAM products to try and mimic APS705 effects gave limited turbidity reduction of Coastal Plain soil suspensions. Combined treatment of gypsum and PAM appears to have either positive or neg.
A Systematic Evaluation of Polyacrylamide for Sediment and Turbidity Control
A Systematic Evaluation of Polyacrylamide for Sediment and Turbidity Control - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook A Systematic Evaluation of Polyacrylamide for Sediment and Turbidity Control write by Richard Allen McLaughlin. This book was released on 2004. A Systematic Evaluation of Polyacrylamide for Sediment and Turbidity Control available in PDF, EPUB and Kindle.
Advancements in Materials Processing Technology, Volume 1
Advancements in Materials Processing Technology, Volume 1 - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Advancements in Materials Processing Technology, Volume 1 write by Rina Sahu. This book was released on . Advancements in Materials Processing Technology, Volume 1 available in PDF, EPUB and Kindle.
Reducing Turbidity of Construction Site Runoff Via Coagulation with Polyacrylamide and Chitosan
Reducing Turbidity of Construction Site Runoff Via Coagulation with Polyacrylamide and Chitosan - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Reducing Turbidity of Construction Site Runoff Via Coagulation with Polyacrylamide and Chitosan write by David Robert Rounce. This book was released on 2012. Reducing Turbidity of Construction Site Runoff Via Coagulation with Polyacrylamide and Chitosan available in PDF, EPUB and Kindle. The U.S. Environmental Protection Agency is in the process of developing a nationwide standard for turbidity in construction site runoff. It is widely expected that this standard cannot be met with conventional erosion and sediment control measures; consequently, innovative practices for managing sediment on construction sites must be developed. The objective of this research was to develop an understanding of how soil characteristics and polymer properties affect the amount of turbidity reduction that can be achieved through flocculation. The polymers used were PAMs, a proprietary product, and chitosan. The charge density of the PAMs ranged from 0% to 50% and the molecular weights ranged from 0.2 to 14 Mg/mol. A protocol for creating modified synthetic stormwater runoff for soil samples was developed and used on soils from seven construction sites. Particle size distributions were used to compare the modified synthetic stormwater runoff with grab samples of stormwater from one site and showed the synthetic runoff was representative of the actual runoff. Flocculation tests were performed on the synthetic runoffs with PAM and chitosan doses from 0.03 to 10 mg/L. The non-ionic PAM, proprietary product, and chitosan were found to be the most effective at reducing the turbidity of all the synthetic runoff below 200 NTU. The high molecular weight anionic PAMs were effective on only two of the seven synthetic runoff samples. Hardness tests were performed indicating interparticle bridging to be the bonding mechanism of the PAM. Electrophoretic mobility tests were performed on two of the soil suspensions and indicated the bonding mechanism of PAM to be interparticle bridging, and the bonding mechanism of chitosan to be a combination of charge neutralization and interparticle bridging. Tests showed as the charge density of the PAM increased, their effectiveness decreased.
