Residence time is a critical factor in determining the size of an open face biofilter. Four test biofilters were constructed with media comprised of yard waste compost and brush chips to compare 8 s. and 4 s. residence time. Biofilter performance was monitored for ten months by measuring pressure drop, moisture content, odor threshold, hydrogen sulfide, and ammonia concentrations. Odor reductio...

The UASB reactor (35 C) was quite efficient for removal of bulk COD (52–74%) from the raw and diluted cultivation medium from the first separation process of baker’s yeasts (the average organic loading rates varied in the range 3.7–16 g COD/l/d). The aerobic-anoxic biofilter (19–23 8C) can be used for removal of remaining BOD and ammonia from anaerobic effluents; however, it had insufficient CO...

Biofiltration for volatile organic compound control in waste gas streams is best operated at steady contaminant loadings. To provide long-term stable operation of a biofilter under adverse contaminant feeding conditions, an integrated bioreactor system with a gas separation membrane module installed after a biofilter was proposed for styrene treatment. Styrene was treated effectively, with aver...

To select the best available packing material for malodorous organic gases such as toluene and benzene, biofilter performance was compared in biofilters employed different packing materials including porous ceramic (celite), Jeju scoria (lava), a mixture of granular activated carbon (GAC) and celite (GAC/celite), and cubic polyurethane foam (PU). A toluene-degrading bacterium, Stenotrophomonas ...

A technique is presented that can be used to estimate the changes in physical structure in a natural biofilter packing medium, such as compost, over time. The technique applies information from tracer studies, grain size distribution, and pressure drop analysis to a model that estimates the number of channels, average channel diameter, number of particles, and specific surface area of the mediu...

The removal of xylene vapors was studied in a biofilter packed with a new hybrid (scoria/compost) packing material at various inlet loads (IL) and empty bed residence times (EBRT) of 90, 60, and 40s. The best performance was observed for EBRT of 90s, where a removal efficiency of 98% was obtained under steady state condition for inlet xylene concentration of 1.34 g m(-3), while a maximum elimin...

In this project, an AromaScan A32S electronic nose and a human panel at the Duke Taste and Smell Lab were used to evaluate the effectiveness of biofilters in reducing the malodors in the exhaust air from swine confinement facilities. Three experiments are reported: 1) detection threshold tests for the electronic nose and human panel for a significant component of swine slurry – acetic acid, 2) ...

Sterile peat used as biofilter medium, was amended with four different concentrations of a nutrient solution, inoculated with a toluene-utilizing consortium. Samples were incubated over 120 days in closed environments microcosms with water vapor and toluene saturation to emulate the conditions prevailing in biofilters. An improvement on toluene consumption rates, associated with microbial growt...

The UASB reactor (35 degrees C) was quite efficient for removal of bulk COD (62-67%) even for such high strength and recalcitrant wastewater as the cultivation medium from the first separation process of baker'syeasts (the average organic loading rates varied from 3.7 to 10.3 g COD/l/d). The aerobic-anoxic biofilter (20 degrees C) can be used for removal of remaining BOD and ammonia from strong...

Reducing the pressure drop in biofilters is important for reduction of energy consumption these devices. Usually, increases with time due to biomass growth within packing material. The aim this study was evaluate aerodynamic processes a laboratory-scale wavy lamellar (WL) plate-type biofilter equipped capillary system humidifying material designed consisted polymer plates (WPP) vertically arran...