Hydrogen sulphide removal from biogas by an anoxic biotrickling filter packed with Pall rings

Abstract

h i g h l i g h t sORP measurement can be used for nitrate supply control. Biogas desulphurization was achieved without a reduction in methane concentration. A high EC CRIT of 120 g S m À3 h À1 can be achieved using polypropylene Pall rings.a r t i c l e i n f o b s t r a c tHydrogen sulphide (H 2 S) is one of the most problematic contaminants in biogas. In this study, a biotrickling filter with a working volume of 2.4 L and packed with polypropylene Pall rings was tested for its ability to remove H 2 S from biogas under anoxic conditions. The influence of the H 2 S inlet concentration, nitrate feeding regime (manual and controlled) and liquid flow rate on the elimination capacity of the biotrickling filter was studied. The results indicate that 99% of the H 2 S was removed for H 2 S inlet loads lower than 120 g S m À3 h À1 when using controlled nitrate feeding by ORP.

Biogas biodesulfurization in an anoxic biotrickling filter packed with open-pore polyurethane foam

“…Soreanu et al [10] found that the minimum required nitrate concentration to maintain the maximum RE (99%), with an IL of 4.9 gS m -3 h -1 , was 20 mg N-NO 3 -L -1 . Fernández et al [14] also found that the lower limit value for nitrate concentration was 20 mg N-NO 3 -L -1 before replacing the medium under a manual dosage supply method.…”

“…OPUF has also been employed in aerobic BTFs for H 2 S removal at high concentrations (10 000 ppmv) from synthetic biogas [22]. Fernández et al [14] worked with an anoxic BTF inoculated with biomass immobilized in OPUF units from the BTF of this study and it was reached a similar biomass concentration of 1.23 × 10 10 ± 0.21 cells (g dry carrier) -1 using polypropylene pall rings as packing material.…”

“…Furthermore, the electron acceptor mass transfer limitation is negligible because the nitrate solubility is very high [91.2 g (100 g) -1 at 25 • C] [15]. Thus, for the production of pipeline grade methane anoxic biofiltration is a more feasible technology as a pretreatment for H 2 S removal than the more commonly used aerobic BTFs [14].…”

“…The biological removal of H 2 S from biogas has been mainly studied under aerobic conditions [5][6][7][8], with very few studies carried out under anoxic conditions [9][10][11][12][13][14]. One advantage of anoxic BTFs over aerobic BTFs is that the biogas is not diluted with air and therefore the methane (CH 4 ) concentration is not reduced [6,13].…”

Removal of hydrogen sulfide in air using cellular concrete waste: Biotic and abiotic filtrations

“…Some biofiltration packing materials have similar densities, such as peanut shells and bagasse (520 kg m -3 ) [30]. Other media have lower densities, such as polypropylene Pall rings (110 kg m -3 ) [31] and wood bark (96 kg m -3 ) [32], whereas others present a high density, such as expanded schist (1248 kg m -3 ; Table 3) and pozzolan (1500 kg m -3 ) [25]. The water retention capacity for cellular concrete was 56 ± 2 %.…”