# Shifting from Conventional to Organic Filter Media in Wastewater Biofiltration Treatment: A Review
## 3 Filter Media Selection on the Efficiency of Biofililtration
### Conventional vs. Organic Filter Media Biofiltration Systems  
Table 1 summarizes the performance of conventional and organic media biofililtration systems. It is well-conceived that biofiltration with conventional filter materials shows remarkable performance in treating various kinds of pollutants such as heavy metals, nitrogenous contaminants, organic compounds, and pharmaceutically active compounds. Conventional biofilter media include sand, anthracite, GAC, zeolite, expanded clay, and plastic media. Among all the conventional filter materials, GAC, sand, and anthracite are the most popular materials. Lately, successful applications of organic waste materials, including peanut shells, coconut fibers, woodchips, rice straws, date palm fibers, and _Agave_ fibers as the biofilter media have been reported. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & \multicolumn{4}{c}{**Conventional Media (Natural)**} \\ \hline
**Type of Filter Media** & **Operating Condition** & **Removal Efficiency** & **Remark** & **Reference** \\ \hline \multirow{4}{*}{Gravel} & Temperature: 20 \({}^{\circ}\)C & & Iron should be removed before & \\  & pH: 7.0–8.3 & & ammonia and manganese & \\  & Airflow rate: 10 L/min & & & oxidation & [69] \\  & DO: 8 mg/L & & & Start-up: 6 months & \\  & & & Treatment of potable water & \\ \hline \multirow{4}{*}{Sand} & Hydraulic flow rate: & COD: 75.0\% & & \\  & 0.35–1.56 m3/m2h & & SS: 97.0\% & \\  & pH: 6.8–7.2 & & TKN: 62.0\% & \\ \hline \multirow{4}{*}{Zeolite (Lab scale)} & Temperature: 12–15 \({}^{\circ}\)C & & COD: 88.0\% & Natural zeolite shows better & \\  & DO: 3 mg/L & & SS: 97.0\% & nitrogen removal due to the ion & \\  & & TKN: 80.0\% & & exchange capacity with NH4-N. & \\ \hline \multirow{4}{*}{Zeolite (Pilot scale)} & Hydraulic load: 1.83, & & & Treatment of textile wastewater & \\  & 2.3 m3/m2h & & BOD: 99\% & & \\  & Temperature: 4–10, & & COD: 92\% & & \\  & 10–18 \({}^{\circ}\)C & & SS: 74\% & & \\  & DO: above 2 mg/L & & TN: 92\% & & \\ \hline \multirow{4}{*}{Sand} & Filtration rate: & & & & \\  & 0.015–0.06 m/h & & & \\  & Nitrogen loading rate: & & & \\  & 8.6–34.3 gN/m3 day & & & Treatment of drinking water & [71] \\  & Surface loading rate: & & & \\  & 8.1–32.5 gN/m2 day & & & & \\ \hline \multirow{4}{*}{Sand} & Iron:arsenic ratio: & & & \\  & 10:1, 20:1, 30:1, 40:1 & Removal of arsenic & & \\  & Filtration rate: & below 5 ug/L & & \\  & 0.212 m3/m2/h & & & \\ \hline \multirow{4}{*}{Anthracite} & Filtration velocity: 0.12, & Turbidity: 50–60\% & & \\  & 0.25 m/h & & DOC: 21\% & \\  & pH: 7.5 & TN: 50\% & & \\ \hline \multirow{4}{*}{Sand} & \multirow{2}{*}{ECBT: 20 min} & \multirow{2}{*}{NH4\_N: 46.6–48.5\%} & \multirow{2}{*}{Treatment of potable water} & \multirow{2}{*}{[72]} \\  & & & & \\ \cline{1-1} \cline{4-4} \cline{5-5}  & & & & \\ \cline{1-1} \cline{4-4} \cline{5-5}  & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Performance of conventional and organic media biofiltration system. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{5}{c}{**Conventional Media (Natural)**} \\ \hline \hline
**Type of Filter Media** & **Operating Condition** & **Removal Efficiency** & **Remark** & **Reference** \\ \hline \multirow{3}{*}{Quartz Sand} & Filtration rate: & \multirow{3}{*}{Iron: 96.2\% Manganese: 97.7\% Arsenic: 98.2\%} & Treatment of groundwater & [74] \\ \cline{1-1} \cline{3-5}  & & & Ammonia: 73.8\% DON: 25.2\% & \\ \cline{1-1} \cline{3-5}  & & Ammonia: 87.9\% DON: 3.4\% & \multirow{3}{*}{Start-up period: 38 days Treatment of river water (Pre-treated with coagulation} & [66] \\ \cline{1-1} \cline{3-5}  & & Ammonia: 76.5\% DON: 49.0\% & \\ \cline{1-1} \cline{3-5}  & & Ammonia: 90.8\% DON: 95.5\% & \\ \cline{1-1} \cline{3-5}  & & Manganese: 95.9\% & \\ \hline \multirow{3}{*}{Sand} & \multirow{3}{*}{HRT: 2 h} & Total Organic: 78.0\% AMmonium: 82.0\% TSS: 91.0\% & \\ \cline{1-1} \cline{3-5}  & & Ammonium: 87.0\% T TEST: 91.0\% & \\ \hline \multirow{3}{*}{Sand} & Temperature: 20–25 \({}^{\circ}\)C & \multirow{3}{*}{NH\({}_{4}\)-N: 60.0\% DCM: 80.