Biodegradazione aerobica cometabolica di cloroformio: studio di fattibilità in reattori a biomassa adesa


Autoria(s): Ciavarelli, Roberta <1981>
Contribuinte(s)

Pinelli, Davide

Data(s)

07/04/2011

Resumo

Chlorinated Aliphatic Hydrocarbons (CAHs) are widespread wastewater and groundwater contaminants and represent a real danger for human health and environment. This research is related to the biodegradation technologies to treat chlorinated hydrocarbons. In particular the study of this thesis is focused on chloroform cometabolism by a butane-grown aerobic pure culture (Rhodococcus aetherovorans BCP1) in continuous-flow biofilm reactors, which are used for in-situ and on-site treatments. The work was divided in two parts: in the first one an experimental study has been conducted in two packed-bed reactors (PBRs) for a period of 370 days; in the second one a fluid dynamics and kinetic model has been developed in order to simulate the experimental data concerning a previous study made in a 2-m continuous-flow sand-filled reactor. The goals of the first study were to obtain preliminary information on the feasibility of chloroform biodegradation by BCP1 under attached-cell conditions and to evaluate the applicability of the pulsed injection of growth substrate and oxygen to biofilm reactors. The pulsed feeding represents a tool to control the clogging and to ensure a long bioreactive zone. The operational conditions implemented in the PBRs allowed the attainment of a 4-fold increase of the ratio of chloroform degraded to substrate consumed, in comparison with the phase of continuous substrate supply. The second study was aimed at identifying guidelines for optimizing the oxygen/substrate supply schedule, developing a reliable model of chloroform cometabolism in porous media. The tested model led to a suitable interpretation of the experimental data as long as the ratio of CF degraded to butane consumed was ≤ 0.27 mgchloroform /mgbutane. A long-term simulation of the best-performing schedule of pulsed oxygen/substrate supply indicated the attainment of a steady state condition characterized by unsatisfactory bioremediation performances, evidencing the need for a further optimization of the pulsed injection technique.

Formato

application/pdf

Identificador

http://amsdottorato.unibo.it/3525/1/Ciavarelli_Roberta_tesi.pdf

urn:nbn:it:unibo-2513

Ciavarelli, Roberta (2011) Biodegradazione aerobica cometabolica di cloroformio: studio di fattibilità in reattori a biomassa adesa, [Dissertation thesis], Alma Mater Studiorum Università di Bologna. Dottorato di ricerca in Ingegneria chimica dell'ambiente e della sicurezza <http://amsdottorato.unibo.it/view/dottorati/DOT256/>, 23 Ciclo.

Idioma(s)

it

Publicador

Alma Mater Studiorum - Università di Bologna

Relação

http://amsdottorato.unibo.it/3525/

Direitos

info:eu-repo/semantics/restrictedAccess

Palavras-Chave #ING-IND/25 Impianti chimici
Tipo

Doctoral Thesis

PeerReviewed