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With the rapid development of modern industry, accelerated urbanization and population rapid growth of various types of wastewater brought increasingly serious harm to the human living environment, especially heavy metals, waste water, more and more serious harm to human health and the environment, effectively remove a variety of heavy metal ions in the wastewater does not cause secondary pollution task is imminent. Papers to Yunnan Yuanjiang Nickel Industry Co., Ltd. Shen nickel residue as the object of study, investigated ferrite law and in treatment simulation Shen nickel residue process conditions and the treatment effect. The residue is acidic and contains large amounts of magnesium ions and heavy metal ions, the purification process of neutralizing acidic waste, while removal of heavy metal ions. Determine the impact Ferrite process parameters: pH value, temperature, mixing time and dosage ratio. The test results show that the optimum operating conditions of the Act as: pH value of 11 or so, the feed ratio of 10, temperature 50 ℃, stirring time 25min. Shen nickel ferrite iron process residue, the concentration of heavy metal ions in water reached wastewater discharge standards; the processed the ferrite sediment to facilitate separation of sediment chemically stable, uniform particle size, magnetic, by processing recycling. The magnetic product is separated from the sediment of the X-ray diffraction pattern of the diffraction pattern and the spinel-type ferrite Fe304 contrast can be seen, the use of the magnetic portion having a spinel-type ferrite in the Act resulting precipitate the crystal structure. But ferrite treatment of wastewater, more difficult heating consumes considerable molysite, a certain amount of sodium hydroxide and heat, and the processing time is longer, so that the processing cost is high. And treatment Nickel residue, comparative study of two treatment process. One is used with a 5% lime milk adjusting the pH to about 9.5, precipitation, filtration, and then the supernatant was adjusted to pH of 12.5 or so; Another is the first value to about 12.5 pH adjusted with 5% lime to precipitate, filter with polymeric ferric sulfate, the supernatant was adjusted to pH 8.5. Sludge return and sludge return on the above two process. The test results show that the two Process the Shen nickel residue, the concentration of heavy metal ions in water are wastewater discharge standards. In the first method, the first alkalization sludge again and in treatment effect than the first acidification and then in and good, the best return sludge flow rates of 40% and 50%, but higher effluent pH can not be directly emissions. For the second method, the top of the sludge return flow of 30% to 40%, the effluent pH is about 8, can be directly discharged, and the return sludge is not used under the same conditions compared to the process, the formation of the sewage the mud moisture content dropped from 93.27% to 90.81%, and reduce the amount of sludge generated about 1/4 of the sedimentation rate was significantly accelerated, while also improving the processing efficiency, to reduce the amount of reagent. Papers by Ferrite and and method of comparison that the the sludge return - lime - Poly Ferric Sulfate callback method process is reasonable, the process is simple, easy to operate, low-cost treatment, it is recommended that the use of this method to the plant Shen nickel residue processing. At the same time test the sludge treatment and disposal advice.
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