Soil immobilization: New concept for biotreatment of soil contaminants

Abstract

A new concept for the development of microbial consortia for the degradation of persistent soil pollutants and for pollutant treatment is proposed. The concept defined as “soil immobilization” is based on the entrapment of soil particles, showing microbial activity in degrading the target pollutant, into a solid membrane with a large pore size distribution. The particular hydrodynamic and mass transfer properties of this system result in a very efficient process. A new type of bioreactor is proposed for carrying out the immobilized soil process. The performance of the system was tested by developing a microbial system for the mineralization of pentachlorophenol (PCP). The results show that the volumetric efficiency of the process for PCP mineralization in the immobilized soil bioreactor is 1–3 orders of magnitude higher than reported literature values. Chlorine and carbon atoms of PCP are both nearly completely (99%) mineralized. ©1998 John Wiley & Sons, Inc. Biotechnol Bioeng 57: 471‐476, 1998.

Removal of two organophosphate pesticides by a bacterial consortium immobilized in alginate or tezontle

“…Karamanev et al [9] found that low concentration of phosphates tended to cause the acidification of the medium, which might affect biodegradation, as well as the population size of the consortium.…”

“…Alginate, k-carragenin and polyvinyl alcohol are used as supports for immobilization; ceramics, diatomaceous earth and porous rocks are used for biofilm formation [9][10][11]. In this work, the main objective was to evaluate the removal of a pesticide mixture composed of methyl-parathion and tetrachlorvinphos using a bacterial consortium immobilized in alginate beads and on tezontle by biofilm.…”

Pesticides in the Environment: Impacts and its Biodegradation as a Strategy for Residues Treatment

“…Encapsulation and biofilm formation methods are commonly used in environmental contexts. Alginate, k-carragenin and polyvinyl alcohol are used as supports for immobilization; ceramics, diatomaceous earth and porous rocks are used for biofilm formation (Karamanev et al, 1998;Davey & Toole 2000;Watnick & Kolter 2000). In order to have a strategy for the treatment of pesticide wastes, we are also making efforts to build bioreactors with bacteria and/or immobilized yeast cells.…”

Bioreactors: Airlift Reactors

“…An immobilized cell ALR by Karamanev et al (452,453) for the biodegradation of recalcitrant compounds has also been proposed for the aerobic bioremediation of simulated diesel fuel contaminated groundwater. It was tested with p-xylene and naphthalene in batch and continuous regimes.…”