Microbial removal of selected volatile organic compounds from the model landfill gas

Abstract

Landfills of municipal waste are an important source of BTEXs in the atmosphere. Biodegrability of these compounds implies that biological methods, such as oxidation in landfill covers, may be an effective way to mitigate emission of these gases. The aim of the study was to evaluate the efficiency of BTEXs removal from landfill gas by biofiltration method and to analyze the influence of methane on BTEXs oxidation rate. The experiments were carried out at laboratory scale continuous flow system (microcosms) and in batch tests. A mixture of municipal waste compost and expanded clay pellets (1:1 of volume) was used as a filter bed material. The model landfill gas (50% vol. of CH4 and 50% vol. of CO2) purged through the microcosms was enriched with toluene (series 1) and all the BTEXs (series 2). The results of 7-month continuous flow experiment showed that removal efficiency of BTEXs in experimental columns ranged from 91 to 100% when the individual trace gases loading rates in model gas were in the range of 0.1-0.2 g m -2 d -1 . The rate of toluene removal, which followed the first order kinetics, depended on the presence of methane in treated gas. About 2-fold higher values of rate constant and 2.5-fold higher values of initial toluene removal rates were observed when no methane was present in the headspaces inside the vials used in the batch tests.

Comparative Evaluation of Selected Biological Methods for the Removal of Hydrophilic and Hydrophobic Odorous VOCs from Air

“…The efficiency and the rate of biofiltration of hydrophilic compounds is mainly dependent on the rate of their biodegradation in the biofilm. However, when hydrophobic gas pollutants are considered, the biofiltration efficiency depends drastically on the transfer rate of the components from the gas phase to the liquid, usually aqueous phase [27][28][29]. This is why biofiltration of hydrophobic compounds precedes with much lower efficiency than hydrophilic compounds and currently the improvement of the efficiency of hydrophobic compounds biofiltration is a challenge in the design of the biological treatment processes [16,30].…”

Landfill Emissions and their Urban Planning and Environmental Health Implications in Port Harcourt, South-South Nigeria

“…Yet, the determination of the gas production rates, generally depend on: a) refuse composition, climate, time (since emplacement); b) nutrient composition and moisture content of the garbage in place; and c) particle size, compaction and buffering capacity. The LFG production rates reported may vary from 0.0007 to 0.0080 m 3 per kg-yr (Robertson & Dunbar, 2005;Zdeb & Lebiocka, 2016).…”

Kinetics of Vinyl Acetate Biodegradation by Pseudomonas fluorescens PCM 2123

“…Before proceeding with the research associated with vinyl acetate biodegradation the effect of pH and temperature on the growth of the selected strain was examined. Pure cultures of Pseudomonas fluorescens PCM 2123 were inoculated into a triplicate sets of 0.5 dm 3 Erlenmeyer flasks containing LB medium. Part of them was adjusted to pH of 5, 6, 7 or 8 and incubated in a shaker at 30 °C, another part was adjusted to pH 7 and incubated at 21, 25, 30 or 35 °C.…”

“…is the rate of growth/utilization of "i" compound and C i its concentration [g i •m -3 ], subscript "0" relates to the parameters at the reactor inlet. The ideal chemostat is continually supplied with sterile fresh nutrient medium in the quantity of * [m 3 •h -1 ] and the cultivation liquid is removed at the same rate ( * ). It means that * = * and the culture volume V R [m 3 ] in the reactor remains constant.…”

“…The development of methods of sewage and exhaust gases treatment is the way of protection against the harmful phenomena of waste accumulation. Among them the biological processes of decomposition of pollutants play a key role because they are very effective even for very small and changeable concentrations of removed compounds as well as for large streams of treated gas [1][2][3][4].…”