Evaluation of polyhydroxybutyrate as a carbon source for recirculating aquaculture water denitrification

Biological denitrification using poly(butylene succinate) as carbon source and biofilm carrier for recirculating aquaculture system effluent treatment

“…2C and D), which showed that the biofilm got mature gradually after acclimation under high nitrate loading. In stage VI, the average denitrification rates of the two reactors were 0.53 ± 0.19 kg NO 3 À -N m À3 d À1 and 0.66 ± 0.12 kg NO 3 À -N m À3 d À1 , which were consistent with SPCL denitrification process (0.64 ± 0.06 kg NO 3 À -N m À3 d À1 ) (Shen et al, 2013), and higher than PCL denitrification process (0.192 ± 0.031 kg NO 3 À -N m À3 d À1 ) (Chu and Wang, 2013), but lower than PHB denitrification process (1 kg NO 3 À -N m À3 d À1 ) (Gutierrez-Wing et al, 2012). This result might be caused by the different degradability and structural characteristics of varied materials and feeding types.…”

“…Moreover, as the bacteria depleted nitrate along with the up-flow reactor column, higher C/N ratio was favor to the activity of sulfate-reducing bacteria (SRB) that uses sulfate as electron donor, which result in the formation of toxic sulfides as the redox potential decreased (Gutierrez-Wing et al, 2012). However, at the bottom the relative high DO and nitrate concentrations are superior to sulfate for electron competition, due to its greater energy yield during the respiratory processes (Gutierrez-Wing et al, 2012). This hypothesis was confirmed by the existence of SRB species (Desulfopila) detected at the middle instead of bottom of reactor II during stage IV (Table 2).…”

“…It can release organic carbon slowly and automatically, which means it can be used directly in the system, and provides an alternative to sustainable RAS. For instance, polycaprolactone (PCL) (Chu and Wang, 2013) or starch/polycaprolactone (SPCL) (Shen et al, 2015), polyhydroxybutyrate (PHB) (Gutierrez-Wing et al, 2012) and poly(butylene succinate) (PBS) (Luo et al, 2014;Wu et al, 2013) were all proved to have high nitrate removal efficiency. Because of the specific material component and reaction product, denitrification based on biodegradable polymers seemed to be more convenient and competitive when the treatment objects have high water quality requirement (e.g., drinking water, groundwater, and RAS water) (Lucas et al, 2008).…”

Simultaneous ammonia and nitrate removal in an airlift reactor using poly(butylene succinate) as carbon source and biofilm carrier

“…In general, a biological reaction is a respiration process in which electron transport is accomplished for energy supplement. In a marine denitrification reactor, carbon source, the only electron donor, is competed for among several substances which play the roles of electron acceptors, such as oxygen, nitrate and sulfate (Gutierrez-Wing et al, 2012). The priority is established mainly by the energy yields, and oxygen provides the most energetic efficiency then followed by nitrate and then sulfate (Lee et al, 2000).…”

Optimization of nitrate removal from wastewater with a low C/N ratio using solid-phase denitrification

“…Therefore, the solid-phase denitrification process is simple, and the risk of overdosing or insufficient carbon dosing can be avoided. Over the past few years, solid-phase denitrification has been investigated for biological denitrification in groundwater (Robinson-Lora and Brennan 2009), drinking water (Zhao et al 2009;Wang and Wang 2013), recirculated aquaculture systems (Boley and Muller 2005;Gutierrez-Wing et al 2012), and landfill leachate (Li et al 2014;Trois et al 2010). However, the application of solid-phase denitrification to nitrogen removal from secondary effluent of WWTPs has rarely been reported.…”