International Congress on Biotechniques for Air Pollution Control ( 2º. 2007. A Coruña)

Permanent URI for this collectionhttps://hdl.handle.net/2183/12678

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Control of methane emissions issuing from lanffills: the Canadian case
(Universidade da Coruña, 2007) Nikiema, Josiane; Heitz, Michèle
[Abstract] During their storage in landfills, wastes are biodegraded, which results in the production of biogas and leachate. Over recent years, the handling of the leachate product has become one of major concern. However, in the case of biogas product, elimination or valorization processes are applied in a smaller proportion, even if the methane emissions, directly related to landfills, are some 25 % of the total anthropogenic methane emissions. Indeed, many older or smaller landfills are deprived of gas collection systems, thereby making impossible the application of gas combustion and/or valorization methods. Therefore, other processes have to be considered, e.g., the biofiltration of methane. In this paper, the results of an experiment, undertaken to confirm the stability of the biofiltration system that has been developed at Université de Sherbrooke by the Biocom group, are presented. At a methane inlet concentration of around 7500 ppmv and a gas flow rate of 0.25 m3/h, the conversion of the biofilter can be maintained at 22 % unchanged for a period of 150 days or more. Even after the cessation of methane feeding and biofilter irrigation for some 2 weeks, the biofilter performance was able to be restored, in only one week, to the same operating level as it was maintained before the deliberate shutdown.
Study of a desulfurization process to convert dibenzothiophene to 2-hydroxybiphenyl by Rhodococcus rhodochrous NRRL (B-2149)
(Universidade da Coruña, 2007) Soares Júnior, Aldo B.; Gurgel, Yanne K. P.; Chagas, Bruna M. E.; Domingos, Thyrone B.; Macedo, Gorete R.; Santos, Everaldo S.
[Abstract] Actually, a great effort is being given to research on biodesulfurization processes, i.e., processes in which sulfur can be removed selectively from sulfur-compound moities without altering its British thermal unit. This effort relies on the fact that fossil fuels (coal and oil) contain organic sulfur compounds that are released after combustion to the environment mainly as SO2 that causes acid rain becoming a potential pollutant. In this work we investigate the biodesulfurization of a model molecule that represents the main class of a group of recalcitrant compounds found in petroleum, Dibenzothiophene (DBT), to produce 2-Hydroxybiphenyl (2-HBP), a sulfur-free compound, by Rhodococcus rhodochrous (NRRL B-2149) using the 4S pathway. Experiments in which R. rhodochrous (NRRL B- 2149) was cultived during exponential growth phase using glucose and DBT as carbon and energy and sulfur sources, respectively, showed that the microorganism follows the 4S metabolic pathway in which DBT is converted to 2-HBP and sulfite. It was also showed that R. rhodochrous (NRRL B-2149) has cell-bounding surface active agents that that facilitates the emulsification of the apolar – water immiscible DBT.
Development of a family of large-scale biothechnological processes to desukphurise industrial gases
(Universidade da Coruña, 2007) Janssen, Albert J.H.; Van Leerdam, Robin; Van Den Bosch, Pim; Van Zessen, Erik; Van Heeringen, Gijs; Buisman, Cees
[Abstract] In this paper an overview is given of a new biotechnological process to remove hydrogen sulphide from gas streams. This process is jointly developed by Wageningen University, Delft University of Technology, Paques B.V. and Shell Global Solutions International B.V. In 1992, the first full-scale installation for H2S removal from biogas was taken into operation whilst in 2002 the first unit for high pressure natural gas desulphurisation was started-up. The removal of sulphur dioxide from flue gasses is feasible as well and in 2006 the first unit went on-stream in China. Currently, more than 75 full-scale plants are in operation worldwide. The formed bio-sulphur has a hydrophilic nature which enables its re-use, e.g. as a fertilizer or fungicide.
Removal of odour and ammnia in ventilation air from growing-finishing pig units using vertical biofilters
(Universidade da Coruña, 2007) Leegaard Riis, Anders
[Abstract] The aim of this study was to investigate the removal of odour and ammonia from outlet air using vertical biofilters in two units with growing-finishing pigs in the winter. Woodchips were used as media in the wall of the biofilters. The air from the pig units was humidified by a high-pressure water system before it reached the biofilters. A total of 56 odour and ammonia measurements were taken at an average outdoor temperature of 5.4 C. The biofilters significantly reduced the odour concentration (OUE/m3) in the outlet air (P<0.001). The measured odour removal efficiency averaged 60 %. In contrast, the biofilters did not reduce the ammonia concentration (ppm) significantly in the outlet air. The hedonic tone of the odour of the air was determined before and after the biofilter. The untreated air was recorded as more unpleasant than the air that had passed through the biofilters. In conclusion, the biofilters were capable of reducing the odour concentration in the outlet air from units with growing-finishing pigs in the winter. The biofilters’ treatment of the air made the odour less unpleasant. However, the biofilters were not capable of reducing the ammonia concentration in the outlet air in the winter
Artificial neural network based model for evaluating performance of immobilized cell biofilter
(Universidade da Coruña, 2007) Rene, Eldon R.; Kim, Junh Hoon; Park, Hung Suck
[Abstract] Artificial neural networks (ANNs) are powerful data driven modelling tools which has the potential to approximate and interpret complex input/output relationships based on the given sets of data matrix. In this paper, a predictive computerised approach has been proposed to predict the performance of an immobilized cell biofilter treating NH3 vapours in terms of its removal efficiency (RE) and elimination capacity (EC). The input parameters to the ANN model were inlet concentration, loading rate, flow rate and pressure drop, while the output parameters were RE and EC respectively. The data set was divided into two parts, training matrix consisting of 51 data points, while the test matrix had 16 data points representing each parameter considered in this study. Earlier, experiments from continuous operation in the biofilter showed removal efficiencies from 60 to 100% at inlet loading rates varying between 0.5 to 5.5 g NH3/m3.h. The internal network parameters of the ANN model during simulation was selected using the 2k factorial design and the best network topology for the model was thus estimated. The predictions were evaluated based on their determination coefficient values (R2). The results showed that a multilayer network (4-4-2) with a back propagation algorithm was able to predict biofilter performance effectively with R2 values of 0.9825 and 0.9982. The proposed ANN model for biofilter operation could be used as a potential alternative for knowledge based models through proper training and testing of the state variables.
Modeling of fungal biofilter for the abatement of hydropic VOCs
(Universidade da Coruña, 2007) Vregara Fernández, Alberto; Revah, Sergio
[Abstract] This work describes the growth of filamentous fungi in biofilters for the degradation of hydrophobic VOCs. The study system was n-hexane and the fungus Fusarium solani B1. The system is mathematically described and the main physical, kinetic data and morphological parameters of aerial hyphae were obtained by independent experiments for model validation. The model proposed in this study describes the increase in the transport area by the growth of the filamentous cylindrical mycelia and its relation with n-hexane elimination in quasi -stationary state in a biofilter. The model describing fungal growth includes Monod-Haldane kinetic and hyphal elongation and ramification. The reduction in the permeability caused by mycelial growth was further related to pressure drop by Darcy’s equation. The model was verified with biofiltration experiments using perlite as support and gaseous n-hexane as substrate.
Menbrane inlet mass spectrometry (MIMS) as a tool for evaluating biological air filters in agriculture
(Universidade da Coruña, 2007) Feilberg, Anders
[Abstract] Membrane inlet mass spectrometry (MIMS) is presented as a new tool for monitoring the removal efficiency of biofilters with respect to odour compounds. The MIMS technique is based on the separation of volatile chemicals and gases from an air stream by a thin silicone membrane adjacent to the ion source of a standard quadropole mass spectrometer. The vacuum conditions of the MS forces the separated compounds to diffuse through the membrane and evaporate in the ion source. The compounds are detected by MS by means of specific molecular ions or fragment ions. It is possible to monitor a number of individual compounds or compound groups contributing to the odour nuisance of livestock facilities. 4-Methylphenol (p-cresol), skatol, indol, 4-ethylphenol, phenol and dimethyltrisulfide give rise to specific signals corresponding to molecular fragments. A variety of carboxylic acids can be detected by signals corresponding to three subgroups of this compound group. The sum of reduced organic sulphur compounds (ROS) are measured by a common signal. The contribution of individual sulphur compounds (mainly methanethiol and dimethyl sulphide) to ROS can be estimated from supplementary MS fragments. MIMS is not suitable for measuring ammonia and hydrogen sulphide for which other methods must be applied. MIMS is suitable for continuous monitoring on-site and has been applied for evaluation of a number of biofilters in the Danish agricultural sector, primarily for treating ventilated air from pig barns.
Continuous monitoring of odours at a biofilter outlet
(Universidade da Coruña, 2007) Sironi, Selena; Capelli, Laura; Céntola, Paolo; Del Rosso, Renato; Il Grande, Massimiliano
[Abstract] The experience matured in the field of biofiltration applied to odour removal enabled to study the correlation between some of the characteristic parameters of the biofilter bed (e.g. T, RH, ?P) with the emitted odour concentration. Today odour measurement can be performed only by classical olfactometry. Classical olfactometry is an expensive and time-consuming method that is not suitable for continuous monitoring as needed by operators of compost facilities. This paper describes the experimental approaches adopted for the development of a system for the continuous monitoring of odour emissions, i.e. an instrument for the repeated air analysis, capable of qualitatively and quantitatively recognizing odours. This work shows the results of the first experiments carried out with the purpose of developing an electronic nose to be applied at a biofilter outlet for the real-time odour concentration measurement and for the detection of the exceeding of a given odour «alarm threshold».
Biofiltration systems for the treatment of waste gas from industrial plants
(Universidade da Coruña, 2007) Phillips, Ian
[Abstract] Bord na Móna Environmental Ltd. has gained valuable experience over the years with the installation of over 500 biofilters, primarily in municipal and industrial wastewater treatment plants, food processing and more recently printing and coating applications. As a result, this paper will deal with the routes of successful biological air treatment and the pitfalls to avoid. Since the mid 1990s Bord na Móna have concentrated their efforts on process development for VOC and industrial applications. New applications include treatment of airstream containing high concentration of H2S, ammonia, VOC or indeed a combination of all three. The paper will cover new developments and new applications notably in solid waste composting plants, and in industrial applications. Success in biofiltration will be shown to be closely linked with in-depth analytical process engineering, accurate characterisation of waste gas streams, control of process conditions for optimisation of biological activity, and the physio-chemical properties of the filter media. Particular attention will be given to the successful application of biofilters for extremely high concentrations of sulphur compounds, up to 5000mg/m3, and the increasing use of biofilters for VOC elimination.
High throughput biofiltration for odour control at water purification plant
(Universidade da Coruña, 2007) Zhukov, Vitaly; Vepritzky, Andrey; Mitin, Leonid; Popov, Vladimir O
[Abstract] A high throughput trickling biofilter for odour control was designed basing on the principles of biotrickling filter technology developed in Moscow Bakh Institute of Biochemistry. All the necessary blocks except a fan: temperature and humidity control unit, a biofilter bed, an irrigation system, a control block and display unit are combined within one compact biofiltration module – a standard container 6000x2400x2400 mm. The plant is thermo-insulated that enables outdoor installation. The biofilter is easily scaled up by adding extra filtration beds. A typical biofiltration module rated for 5,000-10,000 m3/h has a contact time of 3-6 s (biofilter bed total volume – 10.5 m3) and a maximum footprint of 14.5 m2. After extensive pilot plant studies the first 5000 m3/h trickling biofilter easily scalable to 20000 m3/h was installed at Moscow Water Works in spring 2007 to control odour emissions - hydrogen sulfide, mercaptanes and other malodorous volatile organic compounds in up to 60 mg/m3 concentration. The performance results of the industrial biofilter are discussed
Comparison of three pilot plants filled with organic materials for the treatment of air pollutants from a composting plant
(Universidade da Coruña, 2007) Bassivière, Sébastien; Ducray, Florence; Renner, Christophe
[Abstract] This study has compared the efficiency of 3 mixes of organic materials [peat + coco fibre; branches (1 vol) + wood (1vol) + peat (1 vol.); + branches (5 vol) + wood (2vol) + peat (1 vol.)] used in biofiltres pilot plants in order to remove Volatiles Organic Compounds (VOCs), Ammonia and Odours Units (O.U.) from process and ambient air of a composting plant. After a period of seeding, 3 different air velocities have been applied (125 m/h, 175 m/h and 200 m/h) during approximately 1 ½ month each. Results show a better NH3 removal in filters containing wood (92% to 98%) than in the one with coco fibre (between 17% and 63%) depending on the air velocity and on the pollutant concentration (from 35 to 60 ppmV). Concerning VOCs the efficiency was globally the same (approx. 75%) and that for each velocity and for a relatively constant inlet concentration of 20 ppmV Carbon equivalent. Differences are less obvious in terms of Odours Unit that is mainly due to the variability of the analysis itself. The coco fibres filter seems to be a little bit worst than the two others what would be in accordance with the pollutant removal efficiency observed.
Biofiltration of bitumen vapours - Operational aspects
(Universidade da Coruña, 2007) Girard, Matthieu; Fanlo, Jean-Louis; Turgeon, Nicolas; Buelna, Gerardo; Lessard, Paul
[Abstract] This study was carried out in response to odour problems around a bitumen mixing and storage plant. The general objective of this study was to determine the potential of biofiltration for the treatment of air containing bitumen vapours. Two pilot-scale biofilters, a single-stage system and a two-stage system, were operated using a synthetic gas for a period of 106 days. Results demonstrated that a period of about 50 days was necessary to reach a steady state. The two biofilters performed very well in regards to H2S, while VOC treatment was much less efficient. Maximum elimination capacities of 25 g·m-3·h-1 for H2S and 5.3 g·m-3·h-1 for VOCs were obtained with the two-stage system. It was possible to establish certain operating conditions necessary for proper operation and to determine that a two-stage system is more efficient for the simultaneous treatment of H2S and VOCs.
Mathematical modeling and simulation of volatile reduced sulfur compounds oxidation in biotrickling filters
(Universidade da Coruña, 2007) Aroca, G.; Cáceres, M.; Prado, S.; Sánchez, C.; San Martín, R.
[Abstract] The odour generated by industrial gaseous emissions causing nuisances generally is due to the presence of volatile reduced sulfur compounds (VRSC) Although a number of microorganisms are known for degrading VRSC, the treatment of a mixture of reduced sulfur compounds remains challenging for several reasons. To resolve these problems two-stage systems have been proposed, in the first reactor H2S is bio-oxidized and in the second the rest of the VRSC mixture, avoiding the inhibition effects of H2S over the bio-oxidation of these compounds. In the systems described the complete oxidation of H2S must be performed in the first reactor, if some H2S pass though out the first reactor it would have an effect on the bio-oxidation of the other VRSC present in the mixture in the second bioreactor. This situation was modelled and simulated, and is presented in this article. The bio-oxidation of H2S and DMS in a biotrickling filter is described through a model of the mass transfer and chemical reaction processes. The biotrickling filter is modeled as a fixed bed of packing material which supports the growth of micro-organisms as biofilms. When air flows in the bed, H2S and DMS are continuously transferred from the gas phase to the biofilm, where they diffuse and are oxidized by aerobic microbial activity. A summary of the equations, results of the simulation and sensibility to the inhibition constants are reported.
A comparative study of the characteristics and physical behaviour of different packing materials commonly used in biofiltration
(Universidade da Coruña, 2007) Dorado, Antoni D.; Gamisans, Xavier; Gabriel, David; Lafuente, Javier
[Abstract] In this study, the characteristics and physical behaviour of 8 different packing materials were compared. The materials were selected according to previous works in the field of biofiltration including organic and inorganic or synthetic materials. Results pre-selected those more acceptable support materials for the main function they have to perform in the biological system: high surface contact, rugosity to immobilize the biomass, low pressure drop, nutrients supply, water retentivity or a commitment among them. Otherwise, pressure drop have been described by means of the respective mathematic expressions in order to include phenomena in the classical biofiltration models.
Suitability of dust and bioaerosols from a pig stable as inoculum for biological air filters
(Universidade da Coruña, 2007) Kristiansen, Anja; Nielsen, Per Halkjær; Nielsen, Jeppe Lund
[Abstract] Biofiltration for removing ammonia and odour compounds from ventilation air of pig stables is a promising approach. In order to reduce the time for starting up a well-functioning biofilter a good inoculum suited for the environment is needed. In this study the microbial identity and quantity of dust and bioaerosols coming from a pig stable were analyzed for its suitability as inoculum. Inoculation of biofilters with dust had similar good ammonia removal capabilities as biofilters inoculated with activated sludge, although analysis of the microbial dust community revealed clear differences. The organic fraction of the dust particles seems to be important for mediating biofilm development on the filter material.
Monitoring and characterization of bacterial populations of two biological air filters during the start up phase
(Universidade da Coruña, 2007) Jovic, Marc; Cabrol, Léa; Ducray, Florence; Gagneux, R.; Lepeuple, A.S.
[Abstract] This study aimed to monitor and characterize bacterial populations of two biological air filters during their start up phase (four months). The main objective of this work was to assess the potentiality of a microbiological approach to better understand the evolution of the bacterial populations within biofilters and therefore help to select biomass carrier media. The two biological filters were operated at full-scale (480 m3), filled with organic materials and dedicated to the removal of ammonia and Volatile Organic Compounds (VOCs). The first step of the work consisted in developing an extraction method for the biomass fixed on the solid supports. The second step investigated biofilters’ microbial ecology using molecular tools: DAPI (4,6-DiAmino-2- PhenylIndole), TVC (Total Viable Counts), FISH (Fluorescent In Situ Hybridization) and SSCP (Single Strand Conformation Polymorphism). The findings of the experiments did not show a significant evolution of total bacterial concentrations in biofilms of both biological filters during their start up phase. However, SSCP data analysis underlined important variations in the composition of bacterial populations. Finally, examination of the results highlighted the interest to inoculate organic media in order to reduce the acclimation time of microbial populations.
Biofilter response to biomass reactivation for VOC treatment
(Universidade da Coruña, 2007) Elías, Ana; Barona, Astrid; Gallastegui, Gorka; Larrañaga, Mikel; Fernández, María
[Abstract] This research has undertaken a comparative study on using a fresh activated sludge or a refrigerated/ reactivated sludge as active biomass source for biofiltration purposes. A sludge sample was initially selected based on the ratio between volatile solid content and total solid content before and after refrigeration at 6 oC for 90 days. The degradation rate of the activated sample for three addition doses of toluene was established before and after refrigeration. The same procedure was also carried out for ethylbenzene and p-xylene after refrigeration/reactivation. Surprisingly, the degradation rate for toluene was higher after refrigeration and the results were very similar for an addition of 2 and 8 µL. Subsequently, one biofilter was inoculated with the activated sample and another with the reactivated sample, and both were fed with toluene ranging from 2.6 to 26.2 g toluene m-3 h-1. Concerning the elimination capacity of both biofilters, no relevant differences were found. It was concluded that the active biomass degrading toluene was not affected by refrigeration, in spite of the fact that the SV/ST ratio decreased after the storage period. The elimination capacity of the other two biofilters (ethylbenzene and p-xylene) was highly influenced by the gas flow rate. 1 INTRODUCTION Environmental regulations for pollution control are frequently enacted before «suitable» (affordable, effective and environmentally friendly) technologies have been fully developed. Amongst biotechnologies, biofiltration is a seemingly simple system whose effectiveness relies on the optimization of several operating parameters and the selection of a suitable packing material and degrading biomass
FT-IR characterization of biofilms formed on engineered biofiltration media treating volatile organic emissions for the forest products industry
(Universidade da Coruña, 2007) Jones, Kim; Khilnani, Mili; Karre, Anand; Santos, Sergio; Paca, Jan
[Abstract] The gaseous emissions from hardboard mill presses at lumber plants contain both volatile and condensable organic compounds, as well as fine wood and other very small particulate material. Biological emissions control for these compounds present several challenges. The biofiltration media provides support and contact between the gas phase contaminants and active microbial cultures attached as biofilms on the media’s surface. As the transformations in the biofilm and the media during optimal biofiltration operations are not well understood, the main aim of this project was to characterize the biofilm formed on the media during the biofiltration process using Fourier Transform Infrared Spectroscopy (FT-IR) and the FT-IR Microscope, and also examine the results along with the performance data of VOC biofiltration field and pilot scale tests. Some differences in the absorbance spectra were observed in the media and biofilm samples collected from the top and the bottom bed of the biofilters. This work suggests that while FT-IR spectral information can provide some useful insights to biofilm coverages and quality within media sections, more work and measurements will be needed to correlate the information to biofiltration performance and optimization.
Odour and H2S degradation in a full scale biofilter with a mineral based organic coated filter media
(Universidade da Coruña, 2007) Frechen, Franz Bernd; Franke, Wolfram; Scholl, Björn
[Abstract] In order to minimize the odorous emissions from sludge storage tanks on the waste water treatment plant «Niederrad» of the city of Frankfurt/Main, about 12.000 m3/h of foul air has to be treated. Due to high Hydrogen-Sulphide (H2S) loads, the installed standard biofilter systems failed operation after one year. Thus, one of the existing filter beds was filled with a mineral based organic coated material; the other one was re-filled at the same time with a standard biofilter media to allow a comparative study. In a long term monitoring program from May 2006 to June 2007, both media were compared regarding degradation of H2S and odour. The one-year measurement program revealed that the mineral high performance media performs much better then the standard organic media.
Removal of dichloromethane from waste gases using a fixed-bed biotrickling filter and a continuous stirred tank bioreactor
(Universidade da Coruña, 2007) Bailón Allegue, Laura; Dopico, Yolanda; Nikolausz, Marcell; Kästner, Matthias; Veiga, María Carmen; Kennes, Christian
[Abstract] A laboratory scale fixed bed biotrickling filter (BTF) and a continuous stirred tank bioreactor (CSTB) have been studied and compared for the elimination of dichloromethane from waste gases. The DCM removal efficiency in the trickling filter was > 85% for inlet loads up to 25 g.m-3.h-1 and a maximal removal capacity of about 170 g.m-3.h-1 was achieved at a load of 350 g.m-3.h-1. The continuous stirred tank bioreactor showed removal efficiencies > 90% for inlet loads up to 120 g.m-3.h-1. At this load the maximal removal capacity of the system was reached, i.e. about 100 g.m-3.h-1. Thus, higher maximum elimination capacities were reached in the BTF while higher removal efficiencies were obtained at high loads with the CSTB. Both systems presented good stability against overloads.

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