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With the increasing amount of urban sewage sludge generated in the wastewater treatment process has also increased. Sludge is not only rich in nutrients, containing refractory metal toxic substances, if not handled properly will result in more serious secondary pollution, toxic heavy metals limit agricultural sludge or sludge brick comprehensive utilization obstacles, so the sludge generated in urban sewage treatment process, the master of heavy metals in the sewage treatment process to move into ways and migration and transformation of sludge disposal and utilization of great significance. Microwave digestion and inductively coupled plasma emission spectrometry (ICP-AES), to Jinan City Water purification plant influent pumping station, the beginning of the sedimentation tank, aeration tank, secondary sedimentation tank, dewatering room processing unit water samples and sludge as the research object, using the BCR sequential extraction method for metal form (acid soluble, reducible and oxidizable) extraction were determined by ICP-AES samples of Cd, Cr, Cu, Mn , Mo, Ni, Pb, Zn and other heavy metals content of heavy metal elements in the distribution and species distribution in each unit aqueous phase and sludge in the sewage treatment process, and using the appropriate mathematical methods for data processing, identify Distribution of Forms of heavy metals in the sewage treatment process, in order to provide a basis for the rationalization of the prevention of pollution of heavy metals in the sludge produced in the municipal sewage treatment plant sewage treatment process and sludge disposal and resource utilization data. Studies have shown that: (1) water purification Jinan City, a sewage treatment plant in the heavy metal elements Cd, Cr, Cu, Pb, Mo, Zn, Ni, Mn content is in line with requirements for sewage treatment plant emission standard GB18918-2002, heavy metal elements Cd, Cr, Cu, Zn content in line with the requirements of agricultural irrigation water quality standard GB5084-92. (2) in the sewage treatment process, most of the heavy metals in sewage elements Cd, Cu, Mn, Mo, Pb can be obtained in the primary settling tank precipitation, partly adsorbed by the activated sludge in the activated sludge treatment stage. Of heavy metals Cd, Cr, Cu, Zn in the primary sludge content higher than the content of heavy metals in sludge, and metal elements Cr, Ni, Zn contrary, in the excess sludge content is higher than primary sedimentation the content of the sludge. The deposition of heavy metal elements in the sludge (3) of the sewage treatment process there is no significant difference, the same advantages of the metal element in the form of the type of mud samples are different, as appropriate to improve or control the acidity of the sewage treatment process may be used, removal of different heavy metals in various stages of processing. (4) BCR sequential extraction method research Distribution of Heavy Metals law: elements Cd, Zn, Pb form to restore state of Mn acid soluble, its Oxidizable the lower percentage (9.3-11.8% ); elements Cr, Cu, Mo main existence form oxidizable, and its acid-soluble percentage is relatively low (<1.2%); elements Ni in the acid-soluble, reducible tristate oxidisable proportionate share is not very different.
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