efficiency of the vermifiltration method in wastewater treatment. The characteristic
of sewage water was greatly improved by applying sawdust to the soil, which could
increase the soil porosity. The development of earthworms, growth, breed, and
survival in the moist environment has been reported by Garkal et al. 2015. The
high concentration of the chemicals can be tolerated by Eudrilus eugeniae and a high
concentration of chemicals is not expected to affect the efficiency of vermifiltration.
Other factors that fluctuate significantly in raw gray water such as pH, organic load,
and temperature have not yet been studied and reported by researchers.
3.3.2 Dairy Wastewater Treatment
The dairy wastewater used as the influent and processed in the vermifiltration and was
found to be excellent for removing COD, NH 4 and total nitrogen (Rodgers et al.
2006). Samal et al. (2017a, b) explored the efficiency and sustainability of an
integrated system consisting of Canna indica and Eisenia fetida, found that
macrophyte-assisted vermifiltration method has been able to reduce BOD and COD
by 75–81%, and total nitrogen by 24–42% from dairy wastewater and it can be used
as an effective and complementary technology for various decentralized wastewater
treatment system. Sinha et al. (2007) studied the vermifiltration of brewery and milk
dairy wastewaters having very high BOD 5 and TSS loadings. Earthworms reduced
the high BOD 5 loads by 99% in both cases and TSS by over 98%. They reported that
the hydraulic retention times (HRTs) of brewery wastewater and dairy wastewater was 3–4 h and 6–10 h respectively. The worms must act instantly in the process as
the wastewater passes through their bodies (degrading the organics, ingesting the
solids and heavy materials). That’s why the wastewater has to be kept in the
vermifilter bed for a reasonable time (HRT has to be within hours, not days) while
the worms act on the wastewater (Sinha et al. 2007). Vermi-biofiltration is a
combination of vermicomposting of traditional filtration methods. Earthworms
body acts as a “biofilter” and the pollutant removal were reported to be BOD 5 -
97.95%, COD-91.64%, TSS-76.39%, and TDS-84.27%. It was reported that oil and
grease content decreased by 84.13% (Telang and Patel 2015). Total dairy wastewater
treatment using coagulation and decantation with the help of aluminum sulfate,
ferrous chloride, and calcium hydroxide have shown the optimum dose concentrations (0.49–0.63 g/L), pH (11–12) and agitation duration (20 min) to obtain an
effluent in accordance with the Moroccan standards for suspended matter, and total
phosphorus with removal of 94% and 89% respectively (Hamdani et al. 2005). The
vermifilter contains aerobic and anaerobic microhabitats that allow the enrichment of
gene-containing microorganisms necessary for the complete transformation of
organic nitrogen into N 2 . The dual nature (aerobic/anaerobic) of vermifilter provides
an ideal ecosystem to facilitate the microbial decomposition and removal of organic
nitrogen from dairy wastewater reducing downstream N load on soil and groundwater without increasing emissions of gasses that accelerate climate change (Lai et al.
2018). Depending on the characteristics of the wastewater to be treated,
44
A. B. Chowdhary et al.
of sewage water was greatly improved by applying sawdust to the soil, which could
increase the soil porosity. The development of earthworms, growth, breed, and
survival in the moist environment has been reported by Garkal et al. 2015. The
high concentration of the chemicals can be tolerated by Eudrilus eugeniae and a high
concentration of chemicals is not expected to affect the efficiency of vermifiltration.
Other factors that fluctuate significantly in raw gray water such as pH, organic load,
and temperature have not yet been studied and reported by researchers.
3.3.2 Dairy Wastewater Treatment
The dairy wastewater used as the influent and processed in the vermifiltration and was
found to be excellent for removing COD, NH 4 and total nitrogen (Rodgers et al.
2006). Samal et al. (2017a, b) explored the efficiency and sustainability of an
integrated system consisting of Canna indica and Eisenia fetida, found that
macrophyte-assisted vermifiltration method has been able to reduce BOD and COD
by 75–81%, and total nitrogen by 24–42% from dairy wastewater and it can be used
as an effective and complementary technology for various decentralized wastewater
treatment system. Sinha et al. (2007) studied the vermifiltration of brewery and milk
dairy wastewaters having very high BOD 5 and TSS loadings. Earthworms reduced
the high BOD 5 loads by 99% in both cases and TSS by over 98%. They reported that
the hydraulic retention times (HRTs) of brewery wastewater and dairy wastewater was 3–4 h and 6–10 h respectively. The worms must act instantly in the process as
the wastewater passes through their bodies (degrading the organics, ingesting the
solids and heavy materials). That’s why the wastewater has to be kept in the
vermifilter bed for a reasonable time (HRT has to be within hours, not days) while
the worms act on the wastewater (Sinha et al. 2007). Vermi-biofiltration is a
combination of vermicomposting of traditional filtration methods. Earthworms
body acts as a “biofilter” and the pollutant removal were reported to be BOD 5 -
97.95%, COD-91.64%, TSS-76.39%, and TDS-84.27%. It was reported that oil and
grease content decreased by 84.13% (Telang and Patel 2015). Total dairy wastewater
treatment using coagulation and decantation with the help of aluminum sulfate,
ferrous chloride, and calcium hydroxide have shown the optimum dose concentrations (0.49–0.63 g/L), pH (11–12) and agitation duration (20 min) to obtain an
effluent in accordance with the Moroccan standards for suspended matter, and total
phosphorus with removal of 94% and 89% respectively (Hamdani et al. 2005). The
vermifilter contains aerobic and anaerobic microhabitats that allow the enrichment of
gene-containing microorganisms necessary for the complete transformation of
organic nitrogen into N 2 . The dual nature (aerobic/anaerobic) of vermifilter provides
an ideal ecosystem to facilitate the microbial decomposition and removal of organic
nitrogen from dairy wastewater reducing downstream N load on soil and groundwater without increasing emissions of gasses that accelerate climate change (Lai et al.
2018). Depending on the characteristics of the wastewater to be treated,
44
A. B. Chowdhary et al.