Treating Wastewater With Heavy Metal Ions With Magnetic Field-Magnetotactic Bacteria Comprehensive Technology

A novel comprehensive wastewater treatment technology is put forward,discussed and probed, combining High Gradient Magnetic Separation (HGMS)with magnetotactic bacteria (MTB). The genre and characteristics of MTBmixture are identified and the optimum operation conditions confirmed. Moreover,competitive adsorption kinetics of two heavy metal ions is explored, andadditionally, the movement mechanics of MTB in the external magnetic field.As the first step, Bacteria from active mud are acclimated on different cultureconditions: aerobic, slightly aerobic and anaerobic. The mixed bacteria are thenmanaged to be isolated and screened out. The results indicate that the bacteria(MTB) in the sludge, effective to uptake heavy metals,can easily be deciphered.Their number is counted by MPN method, and some of the characters areobserved by electron microscope.Simultaneously, absorption tests on sorts of heavy metal ions are conducted inprescribed static wastewater. And consequently, the kinds of heavy metal ionssuitable for MTB absorption are selected. Then, the operation conditions arestudied for continuous experiments. Based on the study of bio-adsorption of singleheavy metal ion, the competitive adsorption kinetics of two heavy metal ions isstudied,a numerical model developed and analytic and numerical solutions areobtained. During the study of the microbic absorption to heavy metal ions withinmagnetic field, the course is found to be affected greatly by pH value and there isan optimum pH value scope for a certain metal,varying with the genre of bacteria.The absorption is mainly on the surface of the microbe so it could reach theabsorption equilibrium soon. The absorption is also slightly affected bytemperature.Under the optimum operating conditions, separation of MTB carrying heavymetals from the wastewater fluid is studied using separators with paralleledstrings and slabs respectively. Visible pictures by Scan Electronic Microscopyhelp to describe the shapes of MTB.With the aid of magnetic field, the movement of MTB is studied. Sportequations in two directions are developed to describe the behavior of MTB.