To investigate the flow behaviors of different size particles in hydrocyclone,a designed process was numerically simulated by the transient solver,where the quartz particles possessing a size distribution were injected into a 100 mm diameter hydrocyclone with the steady water field and air core inside.A lab experimental work has validated the chosen models in simulation by comparing the classification efficiency results.The simulated process shows that the 25 μm quartz particles,close to the cut size,need much more time than the finer and coarser particles to reach the steady flow rate on the outlets of hydrocyclone.For the particles in the inner swirl,with the quartz size increasing from 5 to 25 μm,the particles take more time to enter the vortex finder.The 25 μm quartz particles move outward in the radial direction when they go up to the vortex finder,which is contrary to the quartz particles of 5 μm and 15 μm as they are closely surrounding the air core.The studies reveal that the flow behaviors of particles inside the hydrocyclone depend on the particle size.
A highly active catalyst of phosphomolybdic acid ~HPMo) was prepared and applied in the catalytic oxidative desulfurization (CODS) system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. The influences of rn(catalyst)/m(oil), V(H202)fV(oil), reaction temperature and reaction time on the fractional conversion of benzothiophene (BT) and dibenzothiophene (DBT) were investigated. GC-MS and micra-coulometric methods were employed to investigate the reaction. The catalyst has high desulfurization activity in the removal of BT and DBT under mild conditions. The recycling experiments indicated that DBT and BT removal could still reach 95.2% and 95.7% after 10 cycles.