| Potassium fluotitanate is an important chemical raw material, widely usedas an additive in aluminum, titanium, boron alloy manufacturing, aluminumprocessing and light metal smelting, and a catalyst of polypropylenesynthesizing. It is all made through the wet process by the domestic fluoridesalt enterprises, and a large amount of wastewater containing iron has beenproduced. At present, the wastewater containing iron is treated by the processof "lime neutralization-aeration oxidation-dense settling separation". Thedischarged water cannot reach to the national discharge standards, and a largeamount of waste slag containing iron with high moisture content, complicatedcomposition which is difficult to be handled has been produced, causingserious secondary pollution. In view of the above problems, in this study, anovel preparation technology of polymerized ferric sulfate chloride (PFCS)using wastewater containing iron from potassium fluotitanate production lineof Hunan Nonferrous Xiangxiang Fluorine Chemical Co. LTD directly wasresearched and developed.(1) According to the characteristics of wastewater containing iron frompotassium fluotitanate production line and the flocculating agent market, theprocess technology line of using the wastewater containing iron directly toprepare PFCS was determined: using wastewater containing iron directly asraw materials without pretreatment and transformation, PFCS was preparedthrough oxidation by the oxidant, hydrolysis, and polymerization by addingcopperas and sulfuric acid to adjust the content of iron ions and acid, andadding some suitable stabilizer under mild conditions.(2) Based on the screening of a large amount of stabilizer, stabilizers ofphosphoric acid and aluminum sulfate that are suitable for this system were determined, and the optimum ratios were determined by optimizing thecombination. It has solved fundamentally the stable problem for preparingPFCS from this kind of wastewater containing iron, which make the stableperiod of PFCS being from one week without adding these stabilizers to sixmonths by adding them, and the technical method of PFCS preparing directlyfrom the wastewater containing iron from potassium fluotitanate productionline to realize successfully.(3) According to the characteristics of the product application market, thetwo product specifications of60g/L and80g/L were determined, and apreparation technique of PFCS with lower concentration was developed. Theproduction technology regulation and post operation were made. A set ofcomplete, stable and mature preparation technology of PFCS utilizingwastewater containing iron from potassium fluotitanate production linedirectly was developed through the optimization of process.(4) The trial product were applied in the leather companies andWastewater Treatment Company of Xiangxiang Leather Industrial Park. Theresults show that, the product is suitable for the treatment of the degreasingand skim hair wastewater from leather companies and the comprehensivetannery wastewater. The product has the following advantages:①Using the wastewater containing iron from potassium fluotitanateproduction line as the main raw materials, the production cost is lower and theprice of production is cheaper;②By retaining a suitable amount of ferrous iron in the product, theflocculation-settlement effect of the first stage of the comprehensive tannerywastewater treatment is better and the discharged water is clearer;③That adding phosphate and aluminum ion, is beneficial for not onlymaking product more stable, but also enhancing the flocculation performance,which makes the flocs formed more tightly, leading to better settling performance. Therefore, there is no scum in the second stage flocculation ofthe comprehensive tannery wastewater treatment;④There is a certain amount of potassium and phosphorus in the products,which are nutrient elements for microbes in oxidation ditch. They arebeneficial for microbes breeding, and making the oxidation ditch runningbetter, and the removal of COD higher.The developed technology method of this topic is novel, and the processroute is simple. It has realized the wastewater containing iron from potassiumfluotitanate production process resource utilization, and turning the waste intotreasure by converting the wastewater into a higher effective flocculant ofPFCS. This technology eliminates the wastewater containing iron pollutionand has solved fundamentally the pollution problem of potassium fluotitanateproduction and the technical bottlenecks restricting the capacity expansion ofpotassium fluotitanate, so it will promote greatly the sound development andthe treatment of wastewater pollution of potassium fluotitanate industry. Theapplication of this technique will offer a higher effective reagent for watertreatment, so it is of great significance for promoting the pollution treatmentof the region and the construction of “two type society” in our province.Therefore, the technology researched and developed has wide applicationvalue and broad application prospects. |
PDF Full Text Request