Modelling of the biofiltration of reduced sulphur compounds through biotrickling filters connected in series: Effect of H2S

Abstract

Background:The behaviour of two biotrickling filters connected in serie (BTF) inoculated with Acidithiobacillus thiooxidans and Thiobacillus thioparus, biodegrading hydrogen sulphide (H2S) and dimethyl sulphide (DMS) simultaneously were studied. A model which considers gas to liquid mass transfer and biooxidation in the biofilm attached to the support is developed. Additionally, a fixed bed biotrickling filter where the microorganism is immobilized in a biofilm which degrades a mixture of H2S and DMS is implemented. Validation of the model was carried out using experimental data obtained at different H2S and DMS loads. Results: The inhibitory effect caused by the presence of H2S on the DMS is observed, which is evidenced by the decrease of the DMS removal efficiency from 80 to 27%, due to the preference that T. thioparus has by simple metabolism. H2S is not affected by the DMS, with removal efficiencies of 95 to 97%, but it decreases at high concentrations of the compound, due to the inhibition of metabolism by high H2S input loads. The model which describes the BFT fits successfully with the experimental results and it has a high sensitivity to inhibition parameters. Conclusions: It is shown that the microorganism has a high affinity for H2S, producing substrate inhibition when the concentration is high. The H2S is able to inhibit the DMS biooxidation, whereas the DMS does not affect the H2S biooxidation.

Application of a novel respirometric methodology to characterize mass transfer and activity of H2S-oxidizing biofilms in biotrickling filter beds

“…Data other than oxygen, which may include the fate of sulfide and its degradation subproducts, is warranted for improving the modeling approach proposed herein, even if data in such type of systems is difficult, even impossible in some cases, to obtain. Most modeling literature, dealing with biofilters and biotrickling filters, report only gas phase data [37][38][39][40] while almost no literature reports data inside biofilms since complex setups are needed and only few probes available. As an example, sulfur production or deposition, which would serve to better understand the H 2 S oxidation cannot be measured directly.…”

Modelación de sistemas de eliminación de olores ofensivos generados por H2S en aguas residuales mediante adsorción con carbón activado

“…En las referencias [11,12,13,14,15,16,17,18,19,20,21] pueden observarse diferentes enfoques y consideraciones de modelación de absorción de olores los cuales fueron estudiados para la elaboración del presente trabajo.…”

Análisis de transferencia de masa en modelos doble-continuos para biofiltración de compuestos orgánicos volátiles (COV)

“…En la Puede observarse ( Figura 7)que Pe m no tiene efecto sobre el tiempo de ruptura del biofiltro, aunque la eficiencia máxima de remoción si presenta una elevación inversamente proporcional con dicho número adimensional. En este contexto, algunos autores han propuesto que Pe m no tiene efecto significativo sobre biofiltros de lecho fijo (Spigno et al, 2004;Saltelli et al, 2006;Silva et al, 2012), sin embargo, estos estudios han sido realizados con un pequeño rango de variación del Pe m (Saltelli et al, 2006), o simplemente no reportados (Silva et al, 2012). Debe tenerse presente que en sistemas donde el lecho eventualmente se saturará por completo, las condiciones hidrodinámicas pueden cambiar en gran medida (con respecto a la condición inicial), con lo que Pe m puede variar algunos órdenes de magnitud (tal como se muestra en la Figura 7).…”