Biodegradation of Recalcitrant Organochlorine Compounds in Fixed Film Reactors

Abstract

Biodegradation in fixed film reactors of chloroorganic compounds in kraft bleaching effluent and in pesticides was studied. Specific biofilm reactors could be adapted for the mineralization of chloroform, chlorophenols, chlorocatechols, chloroguaiacols, chloroveratroles and chlorinated resin acids in bleaching effluent and for chlorophenols in spills of pesticides for blue stain and wood rot. Mineralization of chloroorganic compounds into inorganic chloride and carbon dioxide occurred in the solid phase of the reactor. The ability to degrade the chlorine compounds could be transferred from one reactor to another by transferring the liquid but no degradation occurred before addition of solids in the reactor. The degradation of pentachlorophenol was most active when softwood bark was used as the solid material It was less active on unglazed pottery, and inactive on glass (beads or fibre), cellulosic fibre, clay and ion exchange resin. The mineralization of the chloroorganics occuring in kraft bleaching effluent was less fastidious about the type of solid materials used. The biofilm grew equally well on softwood bark, ion exchange resin and various types of plastic and fiber.

The Influence of dairy manure on atrazine and 2,4-dichlorophenoxyacetic acid mineralization in pasture soils

“…Easily degradable soil organic matter has been demonstrated to increase the degradation rate of numerous xenobiotic compounds (Kuwatsuka and Igarshi 1975;Salkinoja-Salonen et al 1983;Valo and Salkinoja-Salonen 1986). High concentrations of nitrogen has been shown to inhibit atrazine and2,4-D mineralization by some mycorrhizal fungi in vitro (Donnelly et al 1993).…”

Degradation of 2,4,6-trichlorophenol by bacteria isolated from secondary sludge of a pulp and paper mill

“…Successful treatment of contaminated wastewater containing chlorinated phenols has been performed in pilot and fi eld-scale studies involving aerobic organisms such as Flavobacterium species and Rhodococcus species (Apajalahti and Sakinoja-Salonen, 1986;Salkinoja-Salonen et al, 1983). In-situ remediation of 2,4,6-TCP studies that were reported previously dealt mainly with soils contaminated with the chlorinated compounds (Baker and Mayfi eld, 1980).…”

Recent developments in cleanup technologies

“…For instance, biofiltration has been used extensively to remove volatile organic compounds from air emissions (Hodge et al, 1991;Kampbell et al, 1987;Leson and Winer, 1991;Medina et al, 1990, vapor-phase bioreactors have treated chlorinated aliphatics in the gaseous state (Folsom and Chapman, 1991;Shields and Reagin, 19921, and fmed film bioredctors have been used for the treatment of a variety of chlorinated aromatic chemicals (Fathepure and Vogel, 1991;Salkinoja-Salonen et al, 1983) and petroleum refinery effluent (Hamoda and Al-Haddad, 1987). With varying success, reactor technologies have been applied to the treatment of soil and water contaminated with the chemicals found in organic wood preservatives, such as creosote (e.g., PAHs) or pentachlorophenol (PCP) (U.S. EPA, 1991a; Blais, 1988;Mueller et al, 199%).…”