Assessing Reuse of Agricultural and Food Residues for Nitrate Attenuation in Porous Media

Abstract

Nitrate pollution in groundwater is related to surplus nitrate fertilizers and animal waste disposal. As high nitrate concentration leads to health concern, mass reduction of nitrate in a contaminated site is important. From the perspective of recent reuse streams, this paper assessed the potential of agricultural and food residues such as rice husk, rice straw and used coffee as a nitrate attenuation material in porous media. Under saturated flow conditions, column experiments were carried out in silica sand with a mixture of residues. KNO3 or NaCl solutions were injected into columns and were analyzed using temporal moment approaches to characterize the mobility of nitrate and chloride ions. The results showed that the mixture of rice straw leads to the increase of the retardation factor. The results also revealed that the use of rice husk and used coffee decreases the mass of both anions, whereas the rice straw has little effect on attenuation of these anions.

Spectroscopic Characterization of a Nigerian Standard Sand: Igbokoda Sand

“…Soil has been described as the most complex biomaterial on Earth and extracting key molecular information such as the binding mechanisms of contaminants and agrochemicals currently challenges the limits of modern science. Furthermore, in order to accurately assess chemical contaminant-soil interactions in the environment, it is vital to study pure mineral standard sand such as the Igbokoda silica sand in its natural state without the presence of any contaminant [10,11].…”