Agriculture Reference
In-Depth Information
Chapter 12
Nano-enhanced Biological Treatment
of Agricultural Wastewater
Yi An and Qi Dong
Abstract Agricultural wastewater is one of the main types in agricultural nonpoint
source pollution and mostly produced by the abusement of fertilizers, pesticides,
and plastic film. Characterized by high BOD and ammonia, agricultural wastewater
is generally degraded by microbial technique, including natural treatment and
anaerobic or aerobic techniques. However, long reaction period and remnant of a
persistent organic cannot be solved appropriately. Recently, nano-materials have
drawn much attention in in situ remediation of groundwater because of their small
particle size and high specific surface area. Especially, it was found that nano-iron
corrosion in water produced molecular hydrogen, which can be used as an electron
donor for autotrophic microbes. And nitrate, perchlorate, trichlorethylene, and
other pollutants could be removed in this process. In addition, a photocatalytic
technology using nano-TiO
2
as photocatalyst was an efficient and safe method for
antibiotic degradation, which was hardly observed in conventional microbial treat-
ment technology. Also, some researchers developed novel methods using
nanofiltration membrane combined with microbial technology for wastewater treat-
ment. The results showed that the quality of effluent including microbiological
indicators, heavy metals, and POPs is in full compliance with the requirements of
drip irrigation.
12.1
Introduction
With the rapid development of agriculture, agricultural demands for water
resources are increasing. However, due to the excessive application of fertilizers,
pesticides, and other agrochemicals, a lot of agricultural wastewater containing
nitrogen, phosphorus, benzene, chlorine, and other pollutants has been generated.
