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With the rapid development of China's modern industry, the development and use of phosphate rock resources plays a particularly important role in the economic development. Big countries of the world production of phosphorus, phosphate rock is rich in resources, however, China's phosphate rock resources development and utilization of small, high-grade ore and low grade ore, mining difficult, more difficult dressing, easy beneficiation less; abroad phosphate rock resources are also limited. The increasing difficulty of mining and mineral processing. At the same time, too much phosphorus into the water, can cause serious environmental pollution - water eutrophication Therefore, the the phosphate recycling problem becomes very urgent and of great significance. The subject comes from western Hubei high phosphorus the oolitic hematite acid leaching drop the phosphorus leaching wastewater, the wastewater turbidity, acid, high phosphorus content, ideally suited to carry out a pilot study of the recovery of phosphate. The topics focus on the problem of high-phosphorus hematite beneficiation high phosphorus wastewater treatment, recycling experiments carried out on the two single phosphate. The test includes the full-precipitation test, secondary washing precipitation test, fractional precipitation, oxidation leaching tests, oxidation wastewater fractional precipitation test, the four-step test of precipitation, flocculation and sedimentation test, wastewater reuse test. After the test, the test material element content in the slag to draw the best recovery test conditions, and the resulting high phosphorus wastewater recycling pilot program. Plus oxidant leaching does not affect the effect of lowering phosphorus, iron recovery rate of leaching tests, and is conducive to the further wastewater fractional precipitation recycling iron phosphate test, the pilot program is a the oxidative leaching drop phosphorus, step-by-step precipitation process subsequent oxidation leaching wastewater. Test the eventual adoption of the four-step precipitation process of oxidative leaching wastewater: first step precipitation neutralizer ferric hydroxide powder and sodium hydroxide standard liquid, after the three-step precipitation neutralizer for calcium oxide powder, precipitation pH intervals are 0.70 to 1 .25,1.25-3.60,3.60-6.00,6.00-9.00. The first step of the preferred test conditions (2): (1) the type and amount of oxidizing leaching oxidant PZH pharmaceutical solution of: 50%, the amount of 11.7L / (t iron ore concentrates); precipitating agent with 5mol / L The standard solution of sodium hydroxide is used in conjunction with iron hydroxide (dosage: 4.0g / L); (3) the second step by adding a small amount of polyacrylamide do flocculant, flocculation stirring speed of not less than 1200rpm, flocculation stirring time is 1 minute to precipitate The time of 5 minutes; (4) a fourth step of adding a polymerization aluminum flocculant, the mixing time and settling time for 20 minutes. Test Results: The first step precipitation test to obtain a purity of 90.19% of the iron phosphate sludge, recycling to 10.2g / L; second step to achieve efficient flocculation and sedimentation; third step is recovery of approximately 90% purity of the calcium phosphate, and the recovered amount was 11.8g / L; fourth step of processing wastewater can be reused in the the iron concentrate acid leaching to drop phosphorus industrial test or discharge standards.
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