| At present, surface water pollution is a serious problem for many developing countries. As industrial and domestic wastewater containing excessive concentrations of organic pollutants is discharged into natural waters, such as rivers and lakes. Water pollution caused by starch production has been reported to be a serious problem in many Asian countries, particularly in China, Thailand, Korea and India. Starch is a kind of important industry matreials, which is applied in food, chemical engineering, weave, medicine, and other industry. There are a lot of corporations to produce starch in China. The high concentration acid organic wastewater is produced in process of starch production, and its pollution is very severity. As far as treatment techniques of high concentration starch wastewater were concerned, anaerobic treatment is a kind of effective technique for organic wastewater, which has been progressed rapidly during recent decade. However, in order to keep the anaerobic biological reactor running normally, the COD concentration of wastewater should be lower than 5000 mg/L. For the highly concentrated organic wastewater, the pretreatment is necessary, such as flocculating. Flocculation is a kind of effective manner to treat high concentration organic wastewater. The typical flocculants are organic polymer flocculants (OPF), inorganic polymer flocculants (IPF) and composite polymer flocculants(CPF). In this thesis, some kinds of polymeric-iron flocculant were successfully prepared. They were used to pretreat high concentration of organic wastewater, the potato starch wastewater which contains starch, saccharides, protein and other soluble substances. They were some new kinds of water treatment chemicals, in the deal with the wastewater which had advantages as follows: the higher of the COD removal value, the good effect of Deodorization and Turbidity Removal.The thesis includes four chapters:Chapter 1: Biotreatment technique of starch wastewater and the study advance of flocculant.On the base of summering the pollution status of strach wastewaster, the treatment technique of strach wastewaster and study advance of flocculant were reviewed.Chapter 2: The preparation and flocculation procedures of the series of Polyferric Sulfate.Na-Bent is used as core in preparation of inorganic polymer flocculants, which afford new kinds of Polyferric sulfate Intercalation Montmorillonite (PBa, PBb) for the first time. They were characterized by FT-IR spectra, TGA/DTA, XRD and EDS. Their images and grain size were analyzed via SEM and grain size distribution. In the weak acid condition, the result of the starch wastewater treatment by PBa as follows: the COD removal rate reached to 68.8%, the COD removal value reached 4378mg/L and decoloration rates reached to above 90%; the result of the starch wastewater treatment by PBb as follows: the COD removal rate reached to 46.4%, the COD removal value reached 4070mg/L and decoloration rates reached to above 80%.Chapter 3: The preparation and flocculation procedures of the series of Polyferric ChlorideThe series of Polyferric Chloride were prepared. They were characterized by FT-IR spectra, TGA/DTA, UV spectra. In the weak acid condition, the result of the starch wastewater treatment by PFC as follows: the COD removal rate reached to 53%, the COD removal value reached 3393mg/L and decoloration rates reached to above 90%; the result of the starch wastewater treatment by PFC-Bent-S as follows: the COD removal rate reached to 60.7%, the COD removal value reached 4384mg/L and decoloration rates reached to 93.8%; the result of the starch wastewater treatment by PFC-Bent-H as follows: the COD removal rate reached to 64.4%, the COD removal value reached 4650mg/L and decoloration rates reached to above 90%.Chapter 4: Effect of Waste Rock carrier in biotreatment of high concentration starch wastewater.Inorganic polymers wast rock were filled in the aerobic pond as microorganisms carrier. The bioreactor system was steadily operated more than one month. The results indicated that temperature was between 18°C and 35°C. pH varied from 5.0 to 7.5. COD concentrations of influent ranged from 2281 to 5909mg/L. The average COD concentrations of effluents were 761mg/L. The maximum remove rate of COD was 81%.
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