Wastewater

About: Wastewater is a research topic. Over the lifetime, 92512 publications have been published within this topic receiving 1256590 citations. The topic is also known as: waste water.

Adsorption of phenols from wastewater.

Abstract: The present work involves an investigation of the possible use of coal, residual coal, and residual coal treated with H3PO4 as a means of removal of phenol from wastewater. The study was realized using batch experiments, with synthetic wastewater having phenol concentration of 1000 ppm. Other low-cost adsorbents such as petroleum coke, coke breeze, rice husk, and rice husk char have also been used. The effect of system variables such as pH, contact time, and temperature has been investigated. The suitability of the Freundlich, Langmuir, and Redlich-Peterson adsorption models to the equilibrium data was investigated for each phenol-adsorbent system. The results showed that the equilibrium data for all the phenol-sorbent systems fitted the Redlich-Peterson model best. Kinetic modeling of removal of phenols was done using the Lagergren first-order rate expression. A series of column experiments were performed to determine the breakthrough curves.

Domestic and industrial water uses of the past 60 years as a mirror of socio-economic development: A global simulation study

Abstract: To enhance global water use assessment, the WaterGAP3 model was improved for back-calculating domestic, manufacturing and thermoelectric water uses until 1950 for 177 countries. Model simulations were carried-out on a national scale to estimate water withdrawals and consumption as well as cooling water required for industrial processes and electricity production. Additionally, the amount of treated and untreated wastewater as generated by the domestic and manufacturing sectors was modeled. In the view of data availability, model simulations are based on key socio-economic driving forces and thermal electricity production. Technological change rates were derived from statistical records in order to consider developments in water use efficiency, which turned out to have a crucial role in water use dynamics. Simulated domestic and industrial water uses increased from ca. 300 km 3 in 1950 to 1345 km 3 in 2010, 12% of which were consumed and 88% of which were discharged back into freshwater bodies. The amount of domestic and manufacturing wastewater increased considerably over the last decade, but only half of it was untreated. The downscaling of the untreated wastewater volume to river basin scale indicates a matter of concern in East and Southeast Asia, Northern Africa, and Eastern and Southern Europe. In order to reach the Millennium Development Goals, securing water supply and the reduction of untreated wastewater discharges should be amongst the priority actions to be undertaken. Population growth and increased prosperity have led to increasing water demands. However, societal and political transformation processes as well as policy regulations resulting in new water-saving technologies and improvements counteract this development by slowing down and even reducing global domestic and industrial water uses.