Biofiltration may be used to control indoor air pollution. In biofiltration, contaminants in a gas stream are degraded by microorganisms and converted to carbon dioxide, water, and biomass. In this study, the CO2 production and the elimination capacity (EC) of toluene at inlet concentrations between 20 and 80 ppm were investigated using three biofilters operated separately with soil as bed material. Results showed soil, with its rich microflora taken to full advantage without inoculants and additional nutrients, biodegraded toluene at removal rates comparable to those in other studies at higher concentrations. The quantity of CO2 produced correlates with the quantity of toluene removed which implies effective biodegradation and suggests stable long-term operation at these low concentrations. Though the concentrations used in this study are not typical toluene indoor concentrations (ppb), results show biofiltration may be effective for indoor air pollution control with proper design considering biomass growth or biofilm structure, concentration, and gas flow rate.
Inhaltsverzeichnis (Table of Contents)
- INTRODUCTION
- MATERIALS AND METHOD
- Soil as bed material
- Biofilter
- Suction Cell
- Experimental Method/Operation
- Analytical Method
- Biofilm Preparation in the Membrane Reactor
- Scanning Electron Micrograph (SEM)
- Water Content of the Soil in the Biofilter
- Performance Indicators
- RESULTS AND DISCUSSION
- Toluene Removal in Reactor 1 and Reactor 2
- Carbon Dioxide Production in Reactor 2
- Toluene Removal in Reactor 3
- The Biofilm in the Membrane Reactor
Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)
This study investigates the degradation of toluene in a soil biofilter with water content control, focusing on the elimination capacity and CO2 production as indicators of biofiltration performance at low concentrations representative of indoor pollution treatment. The research also examines the impact of low pollutant concentrations on biofilm structure in a membrane reactor.
- Effectiveness of soil biofilters for indoor air pollution control.
- Impact of low toluene concentrations on biofiltration performance.
- Role of biofilm structure in toluene degradation.
- Measurement of CO2 production as an indicator of biofiltration efficiency.
- Comparison of performance between soil biofilters and membrane reactors.
Zusammenfassung der Kapitel (Chapter Summaries)
- INTRODUCTION: This chapter introduces the problem of indoor air pollution caused by volatile organic compounds (VOCs) like toluene. It highlights the need for effective and sustainable solutions, particularly for energy-efficient buildings. Biofiltration is presented as a promising alternative to conventional treatment methods, emphasizing its advantages in terms of environmental friendliness and cost-effectiveness. Challenges related to biofiltration are discussed, including water content control, clogging due to biomass accumulation, and the difficulty in sustaining microbial populations at low pollutant concentrations.
- MATERIALS AND METHOD: This chapter details the experimental setup and procedures. It describes the soil used as bed material, the biofilter reactors with water content control, the suction cell mechanism, and the analytical methods employed for measuring toluene concentrations, water content, and CO2 production. The biofilm preparation method used in the membrane reactor is also explained, along with the scanning electron microscopy (SEM) techniques used to analyze biofilm structure.
- RESULTS AND DISCUSSION: This section presents the experimental findings and their interpretation. The removal efficiency of toluene in the two differential reactors (Reactor 1 and Reactor 2) is discussed, with focus on the elimination capacity (EC) as a function of toluene concentration. The relationship between CO2 production and EC in Reactor 2 is analyzed, highlighting the correlation between these parameters and their implications for assessing biofiltration performance. The performance of the membrane reactor (Reactor 3) is evaluated based on surface elimination capacity (SEC), showing the influence of toluene loading rate on the degradation process. Finally, the structure of the biofilm in the membrane reactor is examined using SEM images, demonstrating the presence of pores and microcolonies within the biofilm.
Schlüsselwörter (Keywords)
Indoor air pollution, toluene, biofiltration, soil biofilter, membrane reactor, biofilm, elimination capacity, carbon dioxide production, surface elimination capacity, microbial degradation, low concentration, environmental technology.
- Quote paper
- Daisy Badilla (Author), 2008, Indoor Air Pollution Control Using a Soil Biofilter, Munich, GRIN Verlag, https://www.hausarbeiten.de/document/1446453
