Natural Treatment and Onsite Processes

Abstract

This paper provides a review of the treatment technologies, which utilize natural processes or passive components in wastewater treatment. The paper primarily focuses on wetland systems and their applications in wastewater treatment (as an advanced treatment unit or decentralized system), nutrient and pollutant removal (single and multiple pollutants, and metals), and emerging pollutant removal (pharmaceuticals). A summary of studies involving the plant (vegetation) effects, wetland design and modeling, hybrid and innovative systems, storm water treatment and other issues such as climate change and greenhouse gas emissions is also provided.

Energy and water autarky of wastewater treatment and power generation systems

“…As discussed before, co-digestion may reduce the energy gap between 2 and 128%. For communities that process wastewater in small quantities and of low strength (low BOD) may consider decentralized natural and onsite treatment processes that are low-tech, and low-cost alternatives such as wetlands and other passive systems [58,59]. As discussed earlier, algae cultivation can be combined with the wastewater treatment process to reduce the energy footprint of these systems and may further produce biogas if possible.…”

The design and operation of subsurface wastewater infiltration systems for domestic wastewater

“…Appropriate permeability of the substrate is a prerequisite for long‐term operation of SWI systems. Substrates with low permeability may suffer from oxygen deficiency, resulting in rapidly deteriorating performance and severe waterlogging and soil clogging (Carroll, Goonetilleke, Khalil, & Frost, ; Dawes, Goonetilleke, & Cox, ; Gude, Truax, & Magbanua, ; Oladoja & Ademoroti, ; Yuan et al., ). Therefore, soil is commonly mixed with 5%–40% cinder, carbon source, or alternative substrate materials to ameliorate the permeability (Fei et al., ; Li et al., ; Wang, Sun, Li, Li, & Pan, ; Zou et al., ).…”