Effects of nitrogen source and empty bed residence time on the removal of styrene gaseous emissions by biotrickling filtration

Abstract

The removal of styrene-polluted air emissions by biotrickling filtration was performed to evaluate the influence of using nitrate and urea as a nitrogen source in the nutrient solution supplied to two bioreactors run in parallel under the same operational conditions for 3 months. The use of urea resulted in less biomass content along the packed bed and better performance of the process, with a maximum elimination capacity (EC) of 57.6 g C m(-3 )h(-1) (removal efficiency (RE) of 88.3% and empty bed residence time (EBRT) of 60 s), which was around 54% higher than when using nitrate. EBRTs of 60, 30 and 15 s were evaluated with a urea-based nutrient supply. By decreasing the EBRT from 60 to 30 s the styrene concentration that could be treated with REs above 80% was almost the half, from 1,100 to 600 mg C m(-3), resulting in ECs of 52.8 g C m(-3) h(-1). Working at 15 s was not possible to obtain REs higher than 40% with a maximum EC of 28.5 g C m(-3) h(-1).

Abatement of styrene waste gas emission by biofilter and biotrickling filter: comparison of packing materials and inoculation procedures

“…Sempere et al (2011) obtained a maximum EC of 57.6 g m -3 h -1 (RE of 88.3%) at an EBRT of 60 s in a BTF packed with Flexiring. The maximum EC obtained for the BTF in this study is a 10% lower than the maximum value observed by Sempere et al (2011), but the EBRT in this study is lower. In terms of styrene removal, the BTF of this study showed a similar performance compared to the peat biofilter and a better performance than coconut fibre biofilter.…”

“…Okamoto et al (2003) tested the Pseudomonas putida strain ST201 in flask experiments, achieving complete styrene degradation after 48 h at concentrations up to 600 mg L -1 . Jang et al (2004) Among the inoculation procedures which were applied in the start-up of bioreactors treating styrene emissions, the use of 2 different inoculum sources has been used: enriched cultures with styrene-degrading strains (Okamoto et al 2003;Jang et al 2004;Kim et al 2005) and activated sludge from wastewater treatment plants (Juneson et al 2001;Sempere et al 2011). From an industrial point of view, the choice of activated sludge as an inoculum presents advantages due to the ease of implementation and lower operational costs.…”

A comparative study of bacterial and fungal‐bacterial steady‐state stages of a biofilter in gaseous toluene removal: performance and microbial community

“…However, higher biomass accumulation was observed with NH 4 + in comparison with NO 3 ‐ . The higher accumulation occurs because NH 4 + could be directly utilized, whereas NO 3 ‐ must first be converted to NH 4 + before being assimilated into biomass and this process consumes a certain amount of energy . Therefore, microorganism growth was retained, and the clogging was relieved.…”

“…27 The higher accumulation occurs because NH 4 + could be directly utilized, whereas NO 3 must first be converted to NH 4 + before being assimilated into biomass and this process consumes a certain amount of energy. 31,32 Therefore, microorganism growth was retained, and the clogging was relieved. However, relevant reports on the effects of nitrogen source on F&B-BF performance and microbial community are relatively few.…”

Experiments and modelling of a biotrickling filter (BTF) for removal of styrene from airstreams

“…In the literature one can find numerous studies whose authors examined the process of biopurification of air from styrene in laboratory‐scale biofilters (BF) and biotrickling filters (BTF) (recently). Pilot studies on the removal of styrene from the air are still scarce thus making its industrial implementation difficult.…”