Bevel-helical gear reducer B2 quan tity H MWeight H HWeight H Mth to B2-FV9-B

Flender/Flender Gear Units/Bevel-helical gear reducer B2

nt production isto undergothefurther processstages of dry- ing, calcination, partial reduction to V2, and final metallurgical reduction to FeV, in order to provide data concerning possible changes in quality, suitability for reaction, burdens on the environment and the workplace ~ dwell time, vanadium concentration of the sohon, reactor type processing 1 \ 3. Results The precipitation of sodium polyvanadate (NPV) has proved to be process worthy of con- sideration. Using suitable parameters: Temperature: 9 to 9 ", pH value: 2.6 to 3.2, Vanadium concentrate: 3 /, Stirring conditions: laminar, anti-settling, the NPV obtained is product with good filtration properties. The danger of 4 creamy (foamy) precipitate is great in the case of non-compliance with the conditions stated and, in particular, in continuous operation. Optimally precipitated NPV is not crystalline product, but nodular agglomerate. The soluble impurities (predominantly Na,SO,) can only be satisfactorilywashed from the macroscopic pores of the filter cake, and only unsatisfactorily from the micropores of the agglomerate. Washin of the NPV is unsatisfactory in the case of creamy precipitates. Reduction of the NPV cannot % performed in pure natural gas, as is usually the case, but only with the addition of approx. 3% by volume ,. Reduction in aqueous suspension with organic reducing agents is not possible. pilot plant has been builtasa continuous precipitation station.The maximum capacityof 1 m3 concentrated lye roughly corresponds to down-scaling factor of 3. The plant runs contin- uously, including filtration. Over test period of several months, working on three-shift basis for lar part of the time, approx. 5 NPVwereprecipitated,filteredandwashed.Thedecisivefactor;lerewastoobtain an optimum precipitate by adapting the parameters throughput, temperature and pH value. The actual precipitation process led to high yields with the above-mentioned parameter sett- ings