%0 Journal Article
%T Effects of pH, Temperature, Dissolved Oxygen, and Flow Rate on Phosphorus Release Processes at the Sediment and Water Interface in Storm Sewer
%A Haiyan Li
%A Liang Liu
%A Mingyi Li
%A Xiaoran Zhang
%J Journal of Analytical Methods in Chemistry
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/104316
%X The effects of pH, temperature, dissolved oxygen (DO), and flow rate on the phosphorus (P) release processes at the sediment and water interface in rainwater pipes were investigated. The sampling was conducted in a residential storm sewer of North Li Shi Road in Xi Cheng District of Beijing on August 3, 2011. The release rate of P increased with the increase of pH from 8 to 10. High temperature is favorable for the release of P. The concentration of total phosphorus (TP) in the overlying water increased as the concentration of DO decreased. With the increase of flow rate from 0.7£¿m£¿s£¿1 to 1.1£¿m£¿s£¿1, the concentration of TP in the overlying water increased and then tends to be stable. Among all the factors examined in the present study, the flow rate is the primary influence factor on P release. The cumulative amount of P release increased with the process of pipeline runoff in the rainfall events with high intensities and shorter durations. Feasible measures such as best management practices and low-impact development can be conducted to control the P release on urban sediments by slowing down the flow rate. 1. Introduction A great number of urban centers are drained by a unique sewer network in which wastewater is mixed with urban runoff water in wet weather [1]. Combined sewer overflows are major sources of intermittent pollution impacting the receiving water in many urban areas serviced by combined sewers [2]. Solid particles that cannot be transported at a certain hydraulic conditions can form deposits carried by wastewater and stormwater [3]. Furthermore, flushing of accumulated sewer sediment is one of the major sources of pollutants in urban wet-weather flow discharges [4]. Solids accumulated in sewer systems carry a variety of pollutants. Phosphorus (P), mainly present in sewage as orthophosphate [5], is one of the significant contaminants in sewer systems. Indeed, orthophosphate is known to quickly interact¡ªuptake and release¡ªwith a wide variety of natural surfaces [6]. As an essential nutrient element, P can be utilized by microorganisms [7]. However, the release of P from the sediment in sewer threats water environment because of the eutrophication of water bodies. Focusing on the latter topic, a number of studies had paid attention to P release from the sediment to various kinds of receiving natural water bodies such as coastal zones [8], lakes [9], and rivers [10]. Some researches examined P release in urban catchment [11]. The release of P from sediments is a complex process [12]. Factors affecting the P release from the sediments have
%U http://www.hindawi.com/journals/jamc/2013/104316/