Biotrickling Filtration of Nitric Oxide

Abstract

A biotrickling filter with blast-furnace slag packings (sizes = 20-40 mm and specific surface area = 120 m 2 /m 3 ) was utilized to treat NO in an air stream. The operational stability, as well as the effects of gas empty-bed retention time (EBRT) and nutrient addition on the removal ability of NO, were tested. Approximately six weeks were required for the development of a biofilm for NO degradation, and a two-week organic carbon deficiency resulted in the detachment of biofilms from the packing surfaces. A steady removal rate of 80% was attained at specified influent NO concentrations of 892 to 1237 ppm and an EBRT of 118 sec. The effluent NO concentration diminished exponentially with enlarging EBRT, with influent NO concentrations of 203-898 ppm, and EBRTs of 25 to 118 sec. Nutrient addition is essential for efficient removal of the influent NO. Mass ratios of C: P: N = 7: 1: 30 and NaHCO 3 : NO-N = 6.3 could be used for practical applications.

Abiotic and Biological Mechanisms of Nitric Oxide Removal from Waste Air in Biotrickling Filters

“…19 Their results were probably not solely caused by a biological removal process but a combination of abiotic reaction with some biological activities. For example, in their experiment, the initial removal efficiency was observed even before the microbe had time to acclimate.…”

“…This process is carried out by two distinct groups of bacteria: the NH 4 oxidizers, which oxidize NH 4 into nitrite (NO 2 Ϫ ), and the NO 2 Ϫ oxidizers, which oxidize NO 2 Ϫ into NO 3 Ϫ . 19,21 The reaction of nitrification by autotrophic organisms is given by the following equation: 22…”

“…It has been reported 19 that the addition of a glucose substrate to an oxidizing nitric oxide (NO) biotrickling filter dramatically improved the performance. In that study, the empty-bed residence times (EBRTs) decreased to ϳ2 min, whereas removals increased to Ͼ80% with inlet NO concentrations at ϳ1000 ppm.…”

A performance study of simultaneous microbial removal of no and SO2 in a biotrickling-filter under anaerobic condition

“…The possible reasons for the superiority of CRBF include: (1) the optimal redox potentials of denitrifying bacteria in CRBF might be prolonged with the aid of SRB (Bailey and Beauchamp, 1971), and (2) heterotrophic SRB contained in CRBF are able to produce slime-like materials that can help to adhere biofilms to the packing surfaces under long-term shear stress (Chou and Lin, 2000). Brazilian Journal of Chemical Engineering Vol.…”

Biological Treatment of Waste Gases Containing Inorganic Compounds

“…Chou and Lin (2000) obtained up to about 80% removal efficiency for NO at inlet concentrations of up to about 1,200 ppmv and EBRT of 118 s. The efficacy of the system and biofilm development was heavily dependent upon nutrient addition. In particular, the presence of carbon source was important for the activity of denitrifying organisms.…”