The way of producing needle-shaped wolldstonite pow-der has never been released, the key to the matter is to get high enough length to -width ratio of the particle. With φ 50 mm horizontal disk type jet mill,rue carr...The way of producing needle-shaped wolldstonite pow-der has never been released, the key to the matter is to get high enough length to -width ratio of the particle. With φ 50 mm horizontal disk type jet mill,rue carry out a series of experiments, and discover that select-ing reasonable technological operating condition, with the aim of weak-ening colliding pulverizing effect and reinforcing rubbing pulverizing effect, is helpful to improve effectively the L-W radio.展开更多
Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystall...Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.展开更多
文摘The way of producing needle-shaped wolldstonite pow-der has never been released, the key to the matter is to get high enough length to -width ratio of the particle. With φ 50 mm horizontal disk type jet mill,rue carry out a series of experiments, and discover that select-ing reasonable technological operating condition, with the aim of weak-ening colliding pulverizing effect and reinforcing rubbing pulverizing effect, is helpful to improve effectively the L-W radio.
文摘Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.
