Wastewater Treatment in Soil as a Function of Residence Time in the Root Zone

摘要

A laboratory study was conducted in an effort to establish a relationship between residence time of land-applied wastewater in the root zone and the degree to which nitrogen is removed from the wastewater. Each of sixteen soil samples of a Cecil gravelly sandy loam was placed in an environmental chamber and seeded to tall fescue at the rate of 22.5 kg/ha. These samples simulated actual field conditions. Soil water (and wastewater) movement through the root zone under wet conditions were described with the aid of a digital simulation model. A procedure was developed to predict the rate and volume of drainage as a function of initial soil moisture content, amount of liquid applied, and time after liquid application.