Preliminary Acclimation Strategies for Successful Startup in Conventional Biofilters

Abstract

The question of how to obtain the best inocula for conventional biofilters arises when an acclimation/adaptation procedure is to be applied. Bearing in mind that no standardized procedure for acclimating inocula exists, certain preliminary strategies for obtaining an active inoculum from wastewater treatment sludge are proposed in this work. Toluene was the contaminant to be degraded. Concerning the prior separation of sludge phases, no obvious advantage was found in separating the supernatant phase of the sludge before acclimation. As far as a continuous or discontinuous acclimation mode is concerned, the latter is recommended for rapidly obtaining acclimated sludge samples by operating the system for no longer than 1 month. The continuous mode rendered similar degradation rates, although it required longer operating time. Nevertheless, the great advantage of the continuous system lay in the absence of daily maintenance and the ready availability of the activated sample.

Biofiltration of high concentrations of methanol vapors: removal performance, carbon balance and microbial and fly populations

“…From day 4 to the end of phase I, the biofilter nearly eliminated all methanol by microbial degradation (EC = 97.3 ± 4.5 g m −3 h −1 ), as confirmed by the CO 2 production (see section entitled ‘Carbon dioxide production’). Thus, inoculum acclimatization is not mandatory, contrary to what is sometimes recommended …”

Potential of non-thermal plasmas for helping the biodegradation of volatile organic compounds (VOCs) released by waste management plants

“…Today the sector of the MBTs of waste proposes an upstream scrubber, which is however inadequate when very high removal efficiencies are required. Moreover, biodegradation is particularly sensitive to changes in the composition of the gaseous effluent and to unsteady airflow rates (Almarcha et al, 2012;Torretta et al, 2013), since microorganisms require time to acclimatize to the new conditions (Elías et al, 2010). During transient conditions, the removal efficiency of biological technologies is limited.…”

Evaluating the impact of water supply strategies on p-xylene biodegradation performance in an organic media-based biofilter

“…The measurement of p-xylene degradation rate in batch assays confirmed the acclimatization of the microbial population present in the liquid phase. This procedure has already been explained in a previous work [17].…”

“…Table 1 summarizes the main characteristics of the packing material [16]. The biofilter was initially irrigated with an activated sludge acclimated according to the procedure published by Elías et al [17] and it was operated in a downflow configuration at 23 ± 2 • C. The flow of pxylene-contaminated air was added from the top of the biofilter at a flow rate of 1-1.5 L min −1 (corresponding to an empty bed residence time ranging from 180 to 270 s) and the contaminated flow was generated by mixing a p-xylene-saturated air stream with a humidified p-xylene-free air stream in different proportions. The non-humidified fraction of air used for p-xylene saturation was a minor fraction of the whole influent air flow and did not significantly impact the moisture of the contaminated air stream entering the biofilter.…”