Research On Adsorption And Model Building Of Biological Activated Carbon Apply In The Water Treatment

Activated carbon has been widely used in feed water supply and wastewater treatment since its remarkable adsorption ability. Especially, once the microorganism was attached on the surface of activated carbon, the regeneration frequencies of the activated carbon is significantly lowered, and the service life span the carbon column is greatly extended. Biological activated carbon (BAC) technology, as one kind of new technology in water treatment industry, has been widely introduced in water and wastewater advanced treatment.Biological activated carbon technology is Method using the large specific surface of activated carbon, developed porosity, and strong adsorption to organic matter and dissolved oxygen to provide a perfect place for microorganism's assembling, growing and reproducing. At the appropriate temperate and good nutrition, physical adsorption and microbial biodegradation functions will be effective synchronously in the BAC.Expanded carbon Bed and Fixed Carbon Bed are widely use in water treatment. Before modeling the expanded carbon bed effectively and conveniently, four assumptions were given. First, the fluid and the particles in the expanded bed are completely mixed, and every granular activated carbon is in the same external environment. Second, there are no spatial differences in the GAC/biofilm particles, and each of the GAC is calculated as a sphere. Third, the process of substrate percolating of the biological membrane and the carbon match the Fick Law. Fourth, microbiological degradation for substrate follow the Monod Law. Then, the mathematic model of the expanded biological carbon bed will be solved by the Galerkin Finite Method.The mathematical model development for the fix biological activated carbon is similar with the process of the model for expanded carbon bed development. First, the fixed bed column was separated by sevral parts, and every part the particle of granular activated carbon is in the same external environment. For the specific characteristics of the fixed bed, frictions among the particles of granular activated carbon are tiny and the shears on the biological membrane outside of the particle of granular activated carbon is little, which means there is no microorganism washed into the bulk fluid.At last, a batch experiment was carrying on for the model's simulation and calibration. It comes out that the predict value is higher than the real concentration of the effluent water, however the tendency of the simulation curves fit the real concentration tendency of effluent water. And the model does owe some significance guidance for the practical production.