A novel approach to biological treatment of contaminated water

摘要

Over the past few years, the focus of our research has been to respond to the recognized needs for novel biological processes that are capable of destroying a wide range of biodegradable pollutants and providing the perfect environment for complex interspecies interactions required for the degradation of environmental contaminants. A new biotechnology process called Biological Permeable Barrier (BPB) was developed to provide high microbial density stable environmental conditions, and protective measures for microbial activities for in-situ bioremediation of contaminated groundwater: This patented technology (U.S. Patent 4337,019) is based on the creation of a structured matrix, or Bio-beads, that provides the perfect environment for organicdegrading microorganisms to establish bio films capable ofdestroying the contaminants in water with remarkable stability and control. For over 240 days, the viability and performance of the BPB (Biobeads) system were shown for biodegradation of a targeted contaminant Z4,6- trichlorophenol ITCP), under a variety of operating and stress conditions (Razavi-Shirazi, 1997). Extensive batch experiments were also conducted to obtain necessary data to determine the rate of TCP diffusion into the Bio-beads, adsorption properties of the Bio-beads, and substrate-use rate of the mixed bioculture as free cells and as immobilized cells (Bio-beads). A simulated model of BPB was also characterized with its porosity permeability and compressibility or deformation under typical field conditions. Our extensive research showed that BPB takes advantage of a controlled biotechnology process to overcome the disadvantages and uncertainties associated with conventional biological processes. A summary of our investigation is presented here.