The New Nano-dust Wet Collection Device Design And Acquisition Research

In this dissertation, a research has been made on design and optimize of a newly nano dust wet collection device, and its collection to the nano TiO₂ dust.First of all, a newly nano dust wet collection device has been designed by adopting a range of wet collection principles, such as the turbulent spray impact and spray. And the device design is optimized by the nano-TiO₂ dust collected experiment. The improved device has been proved with convenient manipulation and high collection efficiency beyond 90%, which is applicable to all particle size collection from the scope of nano to micron.Secondly, by way of measuring the contact angle between a variety of solvent and nano-TiO₂ powder, to ensure of the distilled water which the contact angle is zero as the trapping water. The study on detection method of samples had indicated that, spectrophotometry method based on II Antipyrine methane show good detection effect to nano TiO₂ samples, as the samples concentration in the range of 0.1mg/L to 3.0mg/L, while the turbidity method has good result of detection to the samples concentration ranged from 0.4 mg/L to 80 mg/L. So the turbidity method had been used for the match method of the device because of its rapidity, simplicity, economy.Finally, the study has indicated that there are some influence factors to the collection efficiency; the biggest one is the inlet air flow, followed by the acquisition time, and the last one is the capture flow rate. Air temperature and humidity have a little effect. But with the storage time of acquisition sample increasing, the collection efficiency of devices will decrease. The best acquisition parameters to concentrations in 0.25 mg/m³ to 0.99 mg/m³ of nano-dust collection are: acquisition time 8h, air flow 400L/h, liquid flow 1.0L/min, and collection efficiency stabilized at above 96%. The best acquisition parameters to concentration in 0.01-0.25 mg/m³ of nano-dust collection are: acquisition time 10h, air flow 400L/h, liquid flow 1.0L/min, and collection efficiency stabilized at above 90%. And TEM characterization of samples has been show that the particle size's diameter was between 30 to 50nm, which is consistent to material product. In all, the device is able to have an excellent collection effect on the nano-dust.